Datasets:

andersonbcdefg

/

pubmed_pairs_part2

like 0

Purification and characterization of the penicillin-binding protein that is the lethal target of penicillin in Bacillus megaterium and Bacillus licheniformis. Protein exchange and complex stability.

The penicillin-binding protein that is thought to be the lethal target of penicillin in Bacillus megaterium (protein 1) has been purified to greater than 95% homogeneity. The membrane-bound penicillin-binding proteins were solubilized with a non-ionic detergent and partially separated from each other by ion-exchange chromatography on DEAE-Sepharose CL-6B. Protein 1 was subsequently purified by covalent affinity chromatography on ampicillin-affinose. Bacillus licheniformis contains an equivalent penicillin-binding protein (protein 1) that can be more readily purified to virtual homogeneity in a one-step procedure. It was separated from the other penicillin-binding proteins by utilizing the observation that in this organism, this particular protein is the only one whose covalent complex with benzylpenicillin subsequently breaks down. Membranes were treated with saturating concentrations of benzylpenicillin followed by the removal of free penicillin and further incubation to allow the complex between benzylpenicillin and protein 1 to break down. The penicillin-binding proteins were then solubilized and applied to a column of ampicillin-affinose to which only protein 1 was bound as the other penicillin-binding proteins still had benzylpenicillin bound to them. Pure protein 1 was eluted from the affinity resin with hydroxylamine. The interaction of benzylpenicillin with purified protein 1 has been studied by separating unbound antibiotic from the benzylpenicillin . protein complex by paper electrophoresis. Benzylpenicillin reacts with the protein rapidly to form a covalent complex and the fully saturated complex has a molar ratio of bound [14C] benzylpenicillin: protein of 0.7:1. The complex breaks down, obeying first-order kinetics, with a half-life of 16 min at 35 degrees C, a value identical to that obtained with the membrane-bound protein. The concentration of benzylpenicillin that results in the formation of 50% of the maximum amount of benzylpenicillin . protein complex is that at which the molar amount of benzylpenicillin present is equal to 50% of the molar amount of penicillin-binding protein, rather than being a measure of any of the kinetic parameters of the binding reaction. This observation may be significant in the interpretation of previous results where the amounts of penicillins needed to kill cells or to inhibit penicillin-sensitive reactions have been expressed as concentrations. The possible importance of the breakdown of beta-lactam . protein complexes in the clinical use of these antibiotics is discussed.

[Quarantine and health control of the squirrel monkey (Saimiri sciureus) (author's transl)].

A total of two hundreds and seventy squirrel monkeys (Saimiri sciureus) of both sexes were imported from South America through an animal dealer of the U. S. A. in eight lots from May, 1973 to July, 1974. They were investigated for the presence of the parasites for a maximum of fifteen months including nine weeks of quarantine period from the time of import. The mortality rate before or immediately after arrival at our laboratory reached 56.7% in the first two lots. This, however, could be reduced later to 4.8% by improving some conditions of transportation. Bacteriological surveys revealed no shigella or salmonella infections during the quarantine period. No tuberculin positive reactors were also detected. Filarial infestations seemed to be common in this species; about 45.5% had adult worms in the peritoneal cavity and about 65% harbored microfilaria in the peripheral blood. Acanthocephla was also found in a high rate in the lower alimentary tracts. It has been suggested that the worms disappear in fifteen months by keeping animals in the intermediate host-free circumstances. The sarcocyst was found in the femoral muscle of 7 (18.9%) of 37 animals examined histologically.

[Demonstration of immunoreactive GIF-like substance in villi and decidua by radioimmunoassay and immunofluorescence (author's transl)].

Since Arimura et al (1975) reported the radioimmunoassay for somatostatin (GIF), the concentration of GIF in various organ and brain regions were determined by radio-immunoassay. Dubois et al (1975) reported that immunohistochemically somatostatin was located in the discrete cells of the pancreas as well as the hypothalamus, and from this result, they presented the concept of local hormone instead of systemic hormone which was up to that time accepted in endocrinology. In this study, we developed the high specific anti-GIF serum using rabbits, and with the micro immunodiffusion method, we demonstrated that the precipitin band formed a circular fusion between the GIF and anti-GIF serum. This pattern of reaction was also seen in decidual immunodiffusion. In addition, we developed the radioimmunoassay for GIF using this anti-serum and measured immunoreactive GIF-like substances in villi and decidua of early pregnancy. The concentration of GIF-like substances with 2 N acetic acid extracted of villi and decidua were 0 to 30 pg/0.1 g dry weight. At the same time, we demonstrated the presence of GIF-like substance-containing cells in the villi and decidua by indirect immunofluorescent method. The intensity of immunofluorescence was in cytotrophoblast rather than syncytiotrophoblast, and decidual stromal cell also reacted to the immunofluorescence.

[Intraluminal diverticulum of the duodenum. Report of a case and review of published cases].

The intraluminal diverticulum of the duodenum is very rare; it is an anatomical sac like formation, located in the interior of the duodenum and communicating with it through an orifice situated a the upper pole of the diverticulum where the wall is covered by mucosa on both faces. It has interesting etiopathogenic problems. We present an observation after reviewing the corresponding literature. It was a 32-year old woman suffering from moderate epigastric pains, pyrosis, chronic constipation, markedly nervous. The epigastric pain was unrelated to food or physical efforts. The physical examination showed slight epigastric pain. The gastroduodenal radiological examination showed in the second part of the duodenum a particular image, pear-shaped, homogeneous, impregnated in barium; this image was surrounded by a radiotransparent halo which changed with the patient's position. It has been seen that the diverticulum changes in size and position in agreement with the peristaltism, without ever obstructing the passage through the duodenum. A review is made of the literature and history of intraluminal diverticulum.

[Role of the gastroenterologist in the fate of the functional gastrointestinal patient. Comparative evaluation in 2 series of patients in the outpatient clinic of the Social Security Gastroenterology department of Barquisimeto].

A comparative evaluation is made of patients with functional digestive diseases in an out-patient clinic of the Social Security of Barquisimeto. In the first group of patients a routine approach was followed while in the second group a brief biographic history is added adapting it to the circumstances of work that exist within this type of clinic. From the information obtained of the destiny of the patients of each group, it is evident that the total approach to the patient is of importance as the only mean possible for an adequate approximation to the patient and the proper management of the case. The problem is presented of the gastroenterologist, overwhelmed by the great technical progress, confronted by the destiny of the functional digestive patient in socialized medicine.

[Effect of repeated administration of glucocorticoid on the glycogen level of mouse muscle (author's transl)].

Glycogen content and glycogen synthetase activity in mouse skeletal muscle (M. gastrocnemius) after single or repeated administrations of glucocorticoid were investigated and compared with those in liver, in a series of experiments to elucidate the biochemical mechanism of steroid myopathy. Results obtained were as follows. After a single administration of triamcinolone acetonide (TA, 5 mg/kg i.p.), glycogen content in muscle increased maximally at about 12 hr and returned to control level at about 24 hr. The I form activity of glycogen synthetase in muscle was increased only 6 hr after a single administration, while the total activity of the enzyme was not significantly changed. Similar results were obtained with the liver. After repeated administrations of TA for one week, the glycogen accumulation in the muscle was lowered markedly as compared with that after a single administration. No increase in synthetase I activity was observed, or rather, the enzyme activity was decreased as compared with that from control. Similar results were obtained with the liver. After single or repeated administrations, blood glucose level decreased slightly, glucose level of muscle was not affected and G-6-P level of muscle increased markedly. These results suggest that the lower accumulation of glycogen in the muscle after repeated administrations of glucocorticoid may be primarily due to an abnormality in the glycogen synthetase system.

The modification of the lone tryptophan residue in human serum albumin by 2-hydroxy-5-nitrobenzyl bromide. Characterization of the modified protein and the binding of L-tryptophan and benzodiazepines to the tryptophan-modified albumin.

The possible function of the lone tryptophan residue of human serum albumin in the stereospecific binding site for indole and benzodiazepine compounds was investigated by chemical modification. This residue can be selectively modified with 2-hydroxy-5-nitrobenzyl bromide. The modification alters the conformation of the albumin only slightly, as revealed by circular dichroism, fluorescence, and ultraviolet absorption measurements. A decrease in the association constants of L-tryptophan and diazepam of about 30 - 50% and a decrease in the extrinsic Cotton effects of four benzodiazepine derivatives of about 10 - 15% were found as specific effects of the tryptophan modification. The tryptophan modification itself did not change the number of binding sites of diazepam and L-tryptophan. It is suggested that the lone tryptophan residue of human serum albumin is not directly involved in the specific binding site for indole and benzodiazepine compounds. However, the modification alters the properties of the binding site either by an incomplete refolding of the albumin after urea treatment, or a more selective allosteric effect of the modified tryptophan residue.

Listeria monocytogenes cell walls induce decreased resistance to infection.

A significant decrease in murine resistance to Listeria monocytogenes was induced by using crude Listeria cell wall fraction (LCWF) and purified Listeria cell walls (PF). When equal amounts of these materials were injected, PF was more effective than LCWF in decreasing resistance. The PF effect was dose dependent when measured either as a decrease in 50% lethal dose of the Listeria challenge or as a decrease in survival time of the infected mice. PF apparently does not act directly on the Listeria since it (i) did not cause a change in in vitro growth of Listeria and (ii) did not increase the virulence of Listeria passaged in vivo or in vitro. The greatest decrease in resistance was observed when both PF and the Listeria challenge were injected intraperitoneally, which may suggest a localized effect. A decrease in resistance was seen when PF was given as early as 3 days before challenge. There was little or no decrease in resistance when PF was given 2 days after the Listeria challenge. Mice previously immunized with live Listeria were immune to Listeria challenge. However, after PF injection the immune mice showed a decreased resistance which was of the same order of magnitude as that seen in unimmunized mice. The effect of PF seems to be at least partially nonspecific, since a decrease in resistance to Salmonella typhimurium could also be demonstrated in PF-treated mice. Phagocytosis of Listeria both in vivo and in vitro did not appear to be inhibited by PF, although the ability of PF-treated mice to kill Listeria in the peritoneal cavity was inhibited.

Post-transcriptional modifications of the anticodon loop region: alterations in isoaccepting species of tRNA's during development in Bacillus subtilis.

Structural similarities of tRNA's were compared using three sets of isoaccepting species that had previously been shown to undergo significant changes in chromatographic elution properties as a function of developmental stage in Bacillus subtilis. Comparisons of the structures of the tRNA's were based on the composition of their modified nucleosides, comparisons of oligonucleotide elution profiles from RPC-5 columns, and two-dimensional electrophoretic fingerprint analysis of oligonucleotides. The tRNA's studied were tRNA(Lys) (1) and tRNA(Lys) (3); tRNA(Tyr) (1) and tRNA(Tyr) (2); and tRNA(Trp) (1) and tRNA(Trp) (2). The results suggest that the difference among these pairs of isoaccepting species is a difference in the degree of post-transcriptional modifications of the anticodon loop region. The nucleosides involved were N(6)-(Delta(2)-isopentenyl)adenosine (i(6)A), 2-methylthio-N(6)-(Delta(2)-isopentenyl)adenosine (ms(2)i(6)A), and an unknown nucleoside K, which occurred in a position analogous to N-[9-(beta-d-ribofuranosyl)purin-6-ylcarbamoyl]threonine. The amounts of i(6)A and ms(2)i(6)A, determined using total tRNA from exponential-or stationary-phase cells, suggest that the thiomethylation of i(6)A is a pleiotropic phenomenon affecting several tRNA species. As opposed to the situation in Escherichia coli tRNA, where ms(2)i(6)A constitutes about 90% of the total hydrophobic nucleosides at all growth stages, B. subtilis tRNA's have i(6)A as the predominant hydrophobic nucleoside in exponential growth and ms(2)i(6)A as the predominant nucleoside in stationary phase. Thus, the enzyme system which forms i(6)A and the enzyme system which thiomethylates i(6)A are not coordinated during growth in B. subtilis as they are in E. coli. It is suggested that these changes in anticodon loop modifications in B. subtilis may be related to changes in the translational apparatus which occur during sporulation.

Physiological role of oxygenated cytochrome o: observations on whole-cell suspensions of Vitreoscilla.

The form of cytochrome o that predominates in Vitreoscilla cells having various levels of respiratory activity was studied by using untreated, frozen-thawed, and starved cells, which had respiratory rates decreasing in the order given. Direct spectral observation revealed that the oxygenated form of cytochrome o predominated during the aerobic steady-state oxidation of endogenous substrate or exogenous glutamate in untreated and frozen-thawed cells and was replaced by the reduced form when the cell suspensions became anaerobic. The respiratory rates, estimated inversely from the time of duration of the steady state, were correlated to the rates of oxygen consumption for the various cells. Oxidized cytochrome o predominated in aerobic starved cells. These results indicate the involvement of three forms of cytochrome o--oxidized, reduced, and oxygenated--in the catalytic and cyclic change of this cytochrome. The oxygenated form also appeared after the addition of hydrogen peroxide to the cells, but only the oxidized form appeared when ethyl hydrogen peroxide was added. The appearance of the oxygenated form with the addition of hydrogen peroxide was probably due to the reaction of the reduced cytochrome with the oxygen that had evolved by the action of catalase present in the cells.

Purification and characterization of NADPH-dependent flavin reductase. An enzyme required for the activation of chorismate synthase in Bacillus subtilis.

NADPH-dependent flavin reductase (required for the activation of chorismate synthase) was purified to homogeneity from cell-free extracts of Bacillus subtilis. The enzyme has a molecular weight of 13,000 as determined by sodium dodecyl sulfate-gel electrophoresis, is specific for NADPH, and requires a divalent metal ion and either FMN or FAD for maximal rates of NADPH oxidation. The enzyme is able to reduce 2,6-dichlorophenolindophenol (DCIP) in the presence of NADPH and a divalent metal ion. Both catalytic activities were completely inhibited by EDTA. The Km for FMN is 1.25 X 10(-5) M and for NADPH 7.8 X 10(-5) M with oxygen as the final electron acceptor, and 3.85 X 10(-4) M with DCIP as the final electron acceptor. The enzyme was also isolated in association with chorismate synthase and dehydroquinate synthase. The enzyme associated with the complex has the same catalytic properties as the dissociated enzyme except that it requires both a divalent metal ion and FMN for DCIP reduction. Maximal enzyme activity was observed when the enzyme was preincubated with FMN and the divalent metal ion. The enzyme complex is easily dissociable and the dissociation of the enzyme complex resulted in the failure of NADPH-dependent flavin reductase to adsorb to phosphocellulose.

Characterization of an endoribonuclease, RNase N, from Escherichia coli.

The properties of the enzyme ribonuclease N were investigated. By comparing the distribution in the cell of RNase N with the bonafide intracellular beta-galactosidase, and the periplasmic alkaline phosphatase enzymes, we showed that RNase N is an intracellular enzyme. Since previous studies suggested that it is an endoribonuclease, it was compared to RNase III, the only other known intracellular endoribonuclease in Escherichia coli. Using homopolymers and co-polymers we found that, while RNase III could digest double-stranded RNA only, RNase N digested single-stranded and double-stranded RNA with similar efficiency. Furthermore, all RNAs used, natural as well as synthetic, were substrates for the enzyme. Using 5 S rRNA as a substrate it was confirmed that the enzyme is an endonuclease. The final products of the reaction of this enzyme are 5'-mononucleotides. The molecular weight of the enzyme is about 120,000 and it seems to contain two subunits which are similar in size. These properties thus differentiate this enzyme from all other known ribonucleases in E. coli.

Improved version of the exoantigen test for identification of Coccidioides immitis and Histoplasma capsulatum cultures.

A rapid and simple method for extracting specific cell-free antigens of Coccidioides immitis and Histoplasma capsulatum from agar slant cultures was developed. The extracts were analyzed in immunodiffusion tests for the presence of C. immitis or H. capsulatum specific antigens. These extracts were compared with culture filtrates of brain heart infusion broth subcultures in tests with 32 isolates of C. immitis and H. capsulatum and 13 other fungi which might be morphologically confused with them. The studies showed that the slant extracts were as useful as the culture filtrates and allowed more rapid identification of C. immitis and H. capsulatum. In every case, when an identification was made by conventional morphological methods, the immunological test yielded correlating results. The immunological tests were positive for two isolates that were converted to their yeast forms only after 4 months of study by conventional tests. The new procedure permits the identification of C. immitis and H. capsulatum 2 days after receipt of a pure mycelial-form culture. The test is recommended for the presumptive identification of C. immitis and H. capsulatum cultures.

Contribution of omega-oxidation to fatty acid oxidation by liver of rat and monkey.

Contributions of omega-oxidation to overall fatty acid oxidation in slices from livers of ketotic alloxan diabetic rats and of fasted monkeys are estimated. Estimates are made from a comparison of the distribution of 14C in glucose formed by the slices from omega-14C-labeled compared to 2-14C-labeled fatty acids of even numbers of carbon atoms and from [1-14C]acetate compared to [2-14C]acetate. These estimates are based on the fact that 1) the dicarboxylic acid formed via omega-oxidation of a omega-14C-labeled fatty acid will yield [1-14C]acetate and [1-14C]succinate on subsequent beta-oxidation, if beta-oxidation is assumed to proceed to completion; 2) only [2-14C]acetate will be formed if the fatty acid is metabolized solely via beta-oxidation; and 3) 14C from [1-14C]acetate and [1-14C]succinate is incorporated into carbons 3 and 4 of glucose and 14C from [2-14C]acetate is incorporated into all six carbons of glucose. From the distributions found, the contribution of omega-oxidation to the initial oxidation of palmitate by liver slices is estimated to between 8% and 11%, and the oxidation of laurate between 17% and 21%. Distributions of 14C in glucose formed from 14C-labeled palmitate infused into fasted and diabetic rats do not permit quantitative estimation of the contribution of omega-oxidation to fatty acid oxidation in vivo. However, the distributions found also indicate that, of the fatty acid metabolized by the whole animal in the environment of glucose formation, at most, only a minor portion is initially oxidized via omega-oxidation. As such, omega-oxidation cannot contribute more than a small extent to the formation of glucose.

Characterization of the effects of Mg2+ on Ca2+- and Sr2+-activated tension generation of skinned rat cardiac fibers.

Submaximum and maximum forces of the cardiac muscle contractile apparatus, activated by Ca2+ or Sr2+, were determined as a function of Mg2+ concentration. Apical left ventricular tissue from Sprague-Dawley rats was broken by homogenization into small bundles of fibers with disrupted sarcolemmas (skinned). Tension generation was activated by and graded according to the concentration of Ca2+ or Sr2+ in solutions bathing the skinned fibers and measured with a photodiode force transducer. Steady-state tensions for various levels of activation at each of four concentrations of Mg2+ (5 x 10(-5), 1 x 10(-3), 5 x 10(-3), and 10 x 10(-3) M) in the bathing solutions were analyzed. Other bathing solution constituents and parameters mimicked significant normal intracellular conditions while providing adequate buffering of [H+], [Ca2+], and [MgATP2-] (magnesium adenosine triphosphate). To assess changes in sensitivity of the mechanical system to activation by Ca2+ (or Sr2+), each submaximum tension was expressed as a percentage of the given fiber bundle's maximum force generated at saturating [Ca2+] (or [Sr2+]) at the same [Mg2+]. When plotted as saturation curves these data demonstrate that increasing [Mg2+] depresses Ca2+ sensitivity of the force-generating mechanism. The Ca2+ and Sr2+ sensitivity of the cardiac force-generating apparatus is similar at every [Mg2+], indicating that the magnitude of Mg2+ effect is similar for both types of activation. However, absolute maximum tensions at saturating activating cation concentration increased as [Mg2+] increased; the effect of Mg2+ on maximum force was proportionately the same for Ca2+ and Sr2+ activation. But because saturating [Ca2+] always resulted in a lower maximum force than saturating [Sr2+], this site of Ca2+-Mg2+ interaction appears distinct from the one influencing Ca2+ sensitivity.

Isotope-release cytotoxicity assay with the use of indium-111: advantage over chromium-51 in long-term assays.

The adaptation of indium-111-oxine (also known as 8-hydroxyquinoline) (111In Ox) chelate for long-term (18-48 hr) isotope-release assays of cell-mediated cytotoxicity (CMC) and its advantages over the use of 51 Cr are described. Labeling of DBA/2 P815 mastocytoma cells with 111InOx resulted in the incorporation of as many as a million counts per minute in 10(5) cells with no reduction in cell viability. 111InOx labeled both mouse and human tumor cells. 111InOx, like 51Cr, primarily labeled cytoplasmic constituents; up to 80% of the label existed in a releasable form. 111InOx was quantitatively released from labeled P815 in response to specifically sensitized C57BL/6 lymphocytes. The high labelling efficiency of 111InOx offered a significant advantage over 51Cr in 18- to 48-hour assays for CMC by reducing the counting error and thus making the assay more precise. Because of its higher labeling efficiency, 111InOx can be used in microcytotoxicity assays. 111InOx has the added advantage of a lower spontaneous release in culture than 51Cr. This feature of 111InOx also makes the calculation of specific isotope release more accurate than that achieved with 51Cr in long-term cytotoxic assays.

Therapeutic effect of immunization with OEP, protease toxoid and elastase toxoid on corneal ulcers in mice due to Pseudomonas aeruginosa infection.

The effectiveness of immunizing mice with protease toxoid (PT) or elastase toxoid (ET) on the corneal ulcerization due to either protease or elastase were investigated. Consequently, mice immunized with either PT or ET were protected from corneal ulcers experimentally induced by the homologous enzyme, either protease or elastase. Similarly, two kinds of rabbit immune sera, anti-PT and anti-ET, were found to prevent corneal ulcers by the homologous enzyme. Then, the therapeutic effects of vaccination with a single or mixed vaccine consisting of one, two or three components, i.e., PT, ET and/or the common antigen (OEP) of Pseudomonas aeruginosa, were examined on corneal ulcers in mice produced by live cultures of the bacteria. For the same purpose, administration of a single or combined rabbit immune sera against PT, ET and OEP was conducted. As a result, vaccination with the three-component-mixed vaccine or administration with rabbit immune sera combined with anti-PT and anti-ET sera in addition to anti-OEP serum, were found to be the most effective in preventing corneal ulceration as well as in treating corneal ulcers in mice.

Medical economics survey-methods study: cost-effectiveness of alternative survey strategies.

The Medical Economics Survey-Methods Study was conducted under contract for the National Center for Health Statistics during 1975-76. The objective was to determine the cost-effectiveness of a variety of strategies under consideration for application in a national survey in 1977. Detailed data on health care utilization and expenditures were collected periodically from a panel of 691 Maryland households over a seven-month period. Issues tested through a random experimental design included the relative effectiveness of monthly versus bimonthly interviews and in-person versus telephone contact. Completeness and accuracy of information were determined through an extensive record check involving all providers and third party payers identified in the household check involving all providers and third party payers identified in the household survey. The results indicate that there are substantial deficiencies in the household reporting and that the household data for all types of medical services would benefit from the availability of record data in order to improve theri accuracy. The frequency of contact (monthly versus bimonthly) had little effect on the accuracy of reporting. Given the higher rate of attrition observed for the monthly procedures and their considerably greater cost, the bimonthly interval appears to offer advantages. In-person contact resulted in significantly better reporting compared with telephone contact in the Baltimore area, but no difference was found in more rural Washington County. Thus, the 10 per cent cost increase for in-person contact may well be justified by the improved accuracy of the data obtained for certain types of populations.

Sarcoplasmic calcium-binding proteins in protochordate and cyclostome muscle: characterization of a new protein from amphioxus.

A sarcoplasmic calcium-binding protein (SCP) has been purified from the muscle of the protochordate Amphioxus and shown to be more similar to invertebrate SCP's than to their counterpart found in vertebrates, i.e. parvalbumins. The Amphioxus protein has a pI of 4.9, is rich in tyrosine and tryptophan, has a molecular weight of 22,000 and binds strongly 2Ca2+ with a pK of 7.88. Magnesium competes with calcium for only one of the two metal-binding sites and induces positive cooperativity in Ca2+ binding. In cyclostome muscle (lamprey and hagfish), no protein with high affinity for Ca2+ or Mg2+ could be found, irrespective of molecular weight. Instead, a protein with moderate affinity for Ca2+ (less than or equal to 10(5) M(-1)) was detected: it has a molecular weight of 60,000 and might be quite ubiquitous, as the presence of a similar protein has been reported both in red and white muscle of vertebrates such as chicken and rabbit.

Functional specialisation in the visual cortex of the rhesus monkey.

Anatomical and functional studies of the visual cortex of the rhesus monkey have shown that it is made up of a multiplicity of distinct areas. These seem to be functionally specialised to analyse different features of the visual environment.

Replication of poly dA and poly rA by a drosophila DNA polymerase.

The activity of a 7.3S-8.3S Drosophila DNA polymerase was characterized in detail using poly dA.p(dT)[unk] and poly rA.p(dT)[unk]. With poly dA.p(dT)[unk], Mg(2+) ion was the preferred divalent cation, and enzyme activity was inhibited by K(+) ion and by spermidine. With poly rA.p(dT)[unk], Mn(2+) ion was the preferred divalent cation and enzyme activity was stimulated by K(+) ion and by spermidine. The dependence of enzyme activity on the concentration of primer-template and on the ratio of primer to template was the same in both reactions. The two enzyme activities were identically inhibited by N-ethylmaleimide. Poly dA was replicated extensively and poly rA was replicated partially. The activation energy for poly dA replication was twice that for poly rA replication. Enzyme activity with poly dA.p(dT)[unk] was more stable to thermal inactivation than was enzyme activity with poly rA.p(dT)[unk]. These studies suggest that the same enzyme responds to both the deoxy- and the ribohomopolymer template but that the mechanisms of replication may be different.

Helical Bacillus subtilis macrofibers: morphogenesis of a bacterial multicellular macroorganism.

Helical bacterial macroorganisms have been produced by the selection of appropriate Bacillus subtilis mutants and the establishment of specific growth conditions. Threadlike fibers ranging in length to approximately 1 cm are produced in fluid culture by the parallel association of many division-suppressed filaments in helical arrangement. A more open ball-like structure of complicated woven architecture may also be produced. Macrostructure morphology is regulated by genetic, physiological, and nutritional factors. The pitch angle of surface filaments in helical macrofibers varies as a function of macrofiber diameter, indicating a flexible response of individual cell surfaces to the forces responsible for helical morphology. Three classes of mutants have been obtained that are concerned with helix directionality: (i) mutants that form only left-handed helix macrofibers, (ii) mutants that form only right-handed helix macrofibers, and (iii) conditional mutants able to form either left- or right-handed helix macrofibers depending upon nutritional environment. Aggregate structures containing both left- and right-handed macrofibers have been obtained by coculturing appropriate mutants. In addition to providing information on the organization of the bacterial cell surface, this new system offers unique and unusual opportunities to study cell-cell interactions, primitive morphogenesis, and the properties of a multicellular bacterial form.

Effects of d-amphetamine on the set point of the thermoregulatory system in rats.

Exposing a rat's tail to an ambient temperature lower than that sensed by the rest of the body causes an increase in body temperature. Pretreatment with d-amphetamine causes an even greater increase in body temperature. Morover, while control rats perceive any ambient temperature below 20 degrees C as 'cold', amphetamine-treated animals only perceive ambient temperatures below 20 degrees C as 'cold'. This effect of d-amphetamine was found not only when the body temperature of the rats was 20 degrees C, but also when the body was kept at ambient temperatures of 15 degrees--4 degrees C. Because this effect of d-amphetamine, i.e., shifting of the reference point among treated rats, was found in two other situations (behavioral thermoregulation and in studying the anorexic effects of d-amphetamine among rats kept at different ambient temperatures), the best explanation is that in addition to the effects of the drug upon some thermal sensory roles, it also causes a change in the value of the set point of the thermoregulatory system, and drug-treated rats perceive ambient temperatures of 10 degrees C as 'normal'.

Experimental analysis of the 'happy hour": effects of purchase price on alcohol consumption.

An experimental analogue of a discount drink policy known as the "happy hour" was used to study the effects of purchase price on drinking behavior. Male volunteers with a prior history of either casual (N=20) or heavy (N=14) drinking were given free access to beverage alcohol during a 20-day period. Approximately half the subjects could purchase alcohol under a single-price condition (50 cents/drink), while a matched group was given a price reduction daily (25 cents/drink) during a three-hour period in the afternoon. The results demonstrated that the afternoon price reduction significantly increased alcohol consumption in both casual and heavy drinkers. Reinstatement of the standard purchase price effectively suppressed drinking in both groups. The findings are discussed in terms of the theoretical and research implications of environmental influences on drinking.

Effect of thiol derivatives on mixed mucus and blood clots in vitro.

The disintegrating effect of three reducing thiol derivatives: [sodium mercaptoethane sulphonate (Mesna), N-acetyl-L-cysteine (NAC) and dithio-1,4-threitol (DTT)] was investigated in vitro upon blood clots formed in the absence or in the presence of tracheobronchial secretions and compared with the effect of iso-osmotic saline solution. The amounts of haemoglobin released from the clots after 30 min incubation and the initial rates of haemoglobin release were compared for the different products at different concentrations. All three reducing agents showed some ability to disintegrate mixed clots to an extent depending on their concentration. After 30 min incubation, statistical analysis showed a highly significant difference in favour of Mesna at the three concentrations used, i.e. 0.1, 1.0 and 10 mmol/1. The initial rate of haemoglobin release in presence of Mesna was at all concentrations significantly higher than that of NAC or DTT. The effects on normal blood clots were much less pronounced. The effectiveness of Mesna in splitting up mixed blood and mucus clots in the management of patients who had inhaled blood is discussed.

Benign meningococcemia in childhood. A report of five cases with clinical and diagnostic remarks.

Five children aged 1/2--10 years with benign meningococcemia are reported. The clinical picture was quite uniform: good general condition, spikes of fever, skin eruptions as maculopapules--sometimes haemorrhagic, appearing in association with febrile periods, and arthralgia (big joints). The diagnosis involves either isolation of meningococci (MC) from blood, demonstration of MC with immunofluorescence in skin eruptions, or a significant elevation of MC antibody titre in connection with typical clinical signs and symptoms. Important differential diagnoses are Henoch-Schönlein syndrome, disseminated gonococcal infection, septicemia of other origins, subacute bacterial endocarditis, viral infections, hypersensitivity reactions and subsepsis allergica. By co-agglutination technique, the causative agent of meningococcemia in 4 of the 5 children was shown to be MC group B. These have some features in common with gonococci, whereby an incorrect diagnosis might be suggested as demonstrated in one of our patients. The question is raised whether MC group B is the main causative agent in benign meningococcemia.

Post partum patterns of circulating FSH, LH, prolactin, estradiol, and progesterone in nonsuckling cynomolgus monkeys.

Circulating levels of FSH, LH, prolactin (Prl), estradiol (E), and progesterone (P) were determined by RIA in four intact and four monkeys luteectomized (CLX) at parturition in order to a) characterize the patterns of these hormones during the puerperium, and b) examine a possible inhibitory role of the "rejuvenated" corpus luteum (CL) on the resumption of follicle growth post partum. In both groups during the first four weeks, FSH and LH were at tonic levels typical of ovulatory cycles. Recurrent puerperal "surges" of FSH, but not LH, unaccompanied by increments in serum E, were observed in both intact and CLX monkeys. No consistent pattern of serum Prl was apparent. CLX was followed by a prompt fall in serum P levels, which were elevated above typical follicular phase levels into the second week post partum in intact monkeys. Menstrual cycles resumed 2-4 months after delivery. Hormonal patterns during the first menstrual cycle post partum were indistinguishable from those observed in pregravidic ovulatory cycles. The findings indicate that in nonsuckling cynomolgus monkeys a) although it secretes progesterone, the puerperal CL does not inhibit the resumption of the ovarian cycle post partum, b) the puerperal ovary is not absolutely refractory to gonadotropins, since initial trials with Pergonal + hCG stimulated ovarian function, and c) ovarian activity during the puerperium may be limited by factors other than the tonic supply of gonadotropins.

Experimental regional cerebral ischemia in the middle cerebral artery territory in primates. Part 3: effects on brain water and electrolytes in the late phase of acute MCA stroke.

Experimental regional cerebral ischemia was produced in the middle cerebral artery (MCA) territory in primates (M. mulatta) by macrosphere embolization. Determinations of percentage tissue dry weight and tissue sodium and potassium concentrations were obtained in samples from the ischemic and non-ischemic hemispheres at various time from 12 to 48 hours after the onset of cerebral ischemia. Samples from the cortex normally supplied by the occluded MCA showed maximal accumulation of edema fluid with fluxes in sodium and potassium in reciprocal directions at 12 hours and similar edematous changes in putamen at 24 hours after embolization By 48 hours after MCA occlusion and despite the presence of infarction, partial reversal was observed in the redistribution of water and electrolytes in these gray matter structures. In contrast to cerebral cortex and putamen, the adjacent subcortical white matter showed progressive increases in water content from 12 to 48 hours and definite increases in tissue sodium with decreases in potassium were not observed until 48 hours after MCA occlusion. This late severe white matter edema associated with cerebral infarction appears to be a major factor responsible for the hemispheric swelling observed at this state.

[Absorption of amino acids from the perfused ovine rumen].

The experiments with extracoroporeal perfusion of sheep rumen were performed [Leng et al., 1977]. Bovine plasma, diluted in a 1:1ratio with an isotonic solution of sodium chloride, was used for four perfusions, and autologous blood was used for two perfusions in the course of 150 minutes. After 60 minutes perfusion 20 g enzymatic casein hydrolyzate were applied to the rumen. The levels of free amino acids in the perfusate were recorded after 60 minutes' perfusion [the first phase of perfusion] and at the end of the experiment [the second phase]. The levels of lysine, aspartic acid and glutamic acid increased after perfusions with bovine plasma during the first phase, the levels of glutamic acid, phenylalanine, and in one case of alanine, increased after perfusions with autologus blood. Simultaneously the level of valine decreased after perfusions with bovine plasma, and after perfusions with blood the levels of arginine and valine, and/or lysine, dropped. During the second phase of perfusion, the levels of all the observed amino acids except methionine [bovine plasma], and/or orginine and methionine [blood] rose in the perfusate. The experiments showed that the level of amino acids in the rumen content presented a decisive factor affecting amino acid absorption from the rumen into the blood. Transformation of the amino acids during their passage through the remen wall may be assumed, and glutamic acid is one of the chief products of this process.

[Occurrence of coccidiosis in calves at one to six months of age, which are housed in a large capacity barn].

One- to six-month-old calves, housed in the large-capacity calf house of the Nová Bystrice state farm in the district of Jindrichův Hradec were studied for the occurrence of coccidia in the period from January 1974 to April 1975. The coccidia found in these animals included nine species of the genus Eimeria: E. zuernii, E. bovis, E. ellipsoidalis, E. subspherica, E. auburnensis. The species E. alabamensis, E. cylindrica, E. wyomingensis and E. bukidnonensis occurred just sporadically. Further, the findings included oocysts of Isopora spp. The oocysts of the coccidia E. wyomingensis and Isopora spp. were found for the first time in Czechoslovakia. The overall extensity of invasion (EI) and intensity of invasion (II) grow with age as follows: (chart: see text) The results suggest that even modern large-capacity calf houses are not free from invasion by coccidia; the calves in the house under study were invaded by ten species. Transition to vegetable feeding is accompanied by a marked rise of the EI of all the species of coccidia found in the animals.

Double test of spontaneous rosettes with sheep and mouse erythrocytes. Statistical studies and usefulness in malignant evolutive and nonevolutive lymphoproliferative diseases.

We have demonstrated the log normality of the distribution of sheep rosette-forming cells and mouse rosette-forming cells' values obtained with lymphocytes isolated from the peripheral blood of 135 healthy human beings and 57 patients suffering from chronic lymphocytic leukemia and well differentiated lymphocytic lymphosarcoma with bone marrow infiltration either in evolution or in remission. In evolutive cases, the absolute numbers of mouse rosette-forming cells rose as well as the lymphocytosis, whereas the absolute numbers of sheep rosette-forming cells were normal or even increased in spite of an impressive drop of their percentage. In nonevolutive cases, the absolute numbers of sheep rosette-forming cells and mouse rosette-forming cells were lowered to half of the normal values as a consequence of the lymphopenia induced by chemotherapeutic agents.

[Experimental investigations on the regeneration of aortic endothelial cells. Automatic and visual evaluation of autoradiograms (author's transl)].

Autoradiographic studies on plane preparations using 3H-thymidine and pulse cytophotometric investigations on scrape preparations of aortic endothelium from 34 rabbits have brought the following results: By means of multiple 3H-thymidine-injections the number of labelled endothelial cells is higher in young growing animals than in older rabbits; pulse cytophotometrically we did not find any indication of polyploidization processes; from that we conclude a decrease of the growth fraction with advancing age. In comparison to visual counting the automatic image analysis is a highly effective method for the evaluation of autoradiograms. After multiple 3H-thymidine applications the mean blacking intensity of the labelled cell nuclei is lower in 2 months old animals than in 12 months old rabbits; that may mean an increase in the S-phase duration of the proliferating endothelial cells of the older animals. In the area with branching sites there are more 3H-thymidine-labelled endothelial cells than in the neighbouring vascular segments. The significance of these findings for the preferential incidence of arteriosclerosis in this area is discussed.

Immunohistochemical localization of intestinal glycosidases.

The presence of antigenic determinants of the following enzymes was detected in enterocytes by the indirect immunofluorescence method: 1. lactase in human biopsy material, 2. sucrase-isomaltase during ontogenesis in the rat. 1. Lactase: The antigenic relationship between rat and human lactase, demonstrated with the isolated enzymes, was utilized for the histochemical localization of human lactase. The indirect immunofluorescence method, using guinea pig antiserum to rat lactase, demonstrated the presence of human lactase in the enterocyte brush border. The usefulness of this method for clinical practice resides in the possibility of detecting enzymatically inactive protein immunologically related to lactase in cases of lactase deficiency, thereby facilitating more detailed classification of these diseases. 2. Sucrase-isomaltase: Guinea pig antiserum to rat sucrase-isomaltase (SI) was prepared. It was used to demonstrate antigenic determinants of the enzyme in the enterocyte brush border of the rat during ontogenesis. Structural SI protein is already present in 3-day-old rats, whereas enzyme activity can first be demonstrated histochemically from the 11th day of life and biochemically, in vitro, not until about the 18th day. We consider that this technique can be used for studying the biogenesis of membrane-bound enzymes.

Staphylococcal endocarditis: clinical observations on 113 patients.

A 10-year analysis of 113 cases of staphylococcal endocarditis seen in two Washington, D.C., hospitals is presented. 96% of the cases occurred in parenteral drug addicts, but 4% complicated septicemia from known foci of infection. Coagulase positive staphylococcus was responsible for 97% of the infection, and the rest were caused by coagulase negative staphyloccus. Except in four patients with previously known cardiac murmurs, infection occurred on normal valves in these patients. Infection was isolated to the tricuspid valve in 71%, to the mitral valve in 6% and to the aortic valve in 3.5% of our cases; and more than one cardiac valve was affected in the remaining patients. All patients were treated with antibiotics based on bacterial sensitivity testing. The mortality from isolated tricuspid endocarditis was 5%, from isolated mitral endocarditis 33%, and from isolated aortic valve endocarditis 100%. The overall mortality was 18%. The better prognosis documented for acute tricuspid endocarditis is related to the much less severe haemodynamic consequences of acute tricuspid regurgitation, and the probably milder consequences of septic pulmonary embolism compared with coronary or cerebral embolism.

Computed tomography: cost and efficacy implications.

Because CT is unique, it has been accepted by physicians with unrestrained enthusiasm. However, the capital investment and cost of maintenance are high, and there has been no orderly program of dispersion despite the profound interest of the regulatory agencies in cost containment. Although the diagnostic accuracy of CT in both the head and body is high, its information gain over other competing imaging methods, particularly those in the abdomen (ultrasound, nuclear medicine), has not been fully documented. In evaluating the cost effectiveness of CT, long-term outcome, while the most important criterion, requires carefully controlled studies over many years. Short-term value may be measured by assessing the degree to which CT furnishes new diagnostic information, its accuracy, its effect on the morbidity and mortality of diagnostic and theraupeutic procedures, its impact on treatment planning, and changes in cost and saving incident to its use. Prospective studies must relate the contribution of CT to that of competing methods and document the impact of additional diagnostic information.

Origin and differentiation of the yolk sac and extraembryonic mesoderm in presomite human and rhesus monkey embryos.

Reexamination of presomite human and rhesus monkey embryos in the Carnegie Collection provides no evidence to corroborate the hypothesis that the trophoblast is the source of all extraembryonic tissues in these embryos. Instead, the present study indicates that the developmental pattern of the yolk sac and extraembryonic mesoderm is homologous to that in other eutharian mammals. The primary yolk sac of 10- to 11-day human blastocysts is partially filled with a meshwork of extraembryonic endoderm, whereas such a meshwork is absent in the rhesus monkey. It is suggested that this endodermal meshwork develops as the result of interstitial implantation in the human embryo. A small secondary yolk sac develops in 12- to 13-day human and macaque embryos as the result of pinching off of a portion of the larger primary yolk sac. Development of a secondary yolk sac in higher primates appears to be related causally to differential rates of expansion of the blastocyst and primary yolk sac within the simplex uterus. The caudal margin of the primitive streak develops precociously in 12- to 14-day human and macaque embryos, and this appears to be the source of all the extraembryonic mesoderm of the chorion, chorionic villi, and body stalk. It is suggested that the peripheral spread of extraembryonic mesoderm plays in inductive role in the development of chorionic villi, similar to other types of epithelial-mesenchymal inductive interactions. In contrast to previous hypotheses, the human and macaque trophoblasts appear to give rise only to additional trophoblast.

Histaminergic pharmacology of primate lower esophageal sphincter.

We have studied the lower esophageal sphincter (LES) response to exogenous histamine and to H1- and H2-blocking agents in the awake baboon. Increasing intravenous bolus doses of histamine produce an increase in LES pressure with a maximum response at a dose of 12 microgram/kg. H1-receptor blockade with chlorpheniramine over a wide dose range did not alter basal LES pressure but did abolish the response of the LES to exogenous histamine. H2-receptor blockade with cimetidine at doses markedly inhibiting gastric acid secretion (2 mg/kg.h) did not alter basal LES pressure or the response of the LES to exogenous histamine. In addition, cimetidine did not alter the response of the LES to pentagastrin and bethanechol. Although histamine and histamine receptors are important in gastric secretion, they appear to have no identifiable role in the maintenance of basal LES smooth muscle tone in the baboon. These results demonstrate the presence of a stimulatory H1 receptor on baboon LES smooth muscle, but provide no evidence for the presence of an H2-inhibitory receptor. As opposed to the parietal cell, the LES response to pentagastrin and bethanechol does not require a H2 receptor.

Effect of low temperature on growth, viability, and synthesis of mycolic acids of Mycobacterium tuberculosis strain H37Ra.

Cultures of Mycobacterium tuberculosis strain H37Ra were grownto early logarithmic phase at 37 degrees C and were incubated at 16 degrees, 20 degrees, and 25 degrees C. The decrease in this ability was more rapid at 20 degrees C than at 16 degrees C. Low-temperature incubation caused decreases in the ratios of mycolic acids and monounsaturated C16-19 fatty acids relative to the total of fatty acids synthesized. It also caused an increase in the ratio of saturated C24-26 fatty acids relative to the total of fatty acids synthesized. These ratios were based on the incorporation of radiolabel from 14C-acetate into fatty acids. These results showed that when M. tuberculosis H37Ra was incubated at low temperatures, it did not adapt by increasing the ratio of unsaturated to saturated fatty acids synthesized. The ability of the cells to synthesize mycolic acids was sharply decreased. These changes may lead to the loss of viability of M. tuberculosos H37Ra. Mycolic acid synthesis is similarly affected by exposure of cells to isoniazid, an antimycobacterial drug.

Placental permeability in the sheep.

The transplacental flux of different radiolabelled substances was measured, according to Fick's principle, in chronically catheterised pregnant sheep (124 to 143 days of gestation). Knowing the uterine blood flow, it was possible to calculate the net flux and derive a permeability coefficient, K. With 14C erythritol, K soon reaches its ultimate value, thus suggesting there is only one rate-limiting step to transfer and no significant middle compartment in the sheep placenta. The comparison of feto-maternal fluxes of different metabolically inert, lipid insoluble molecules (urea, erythritol, mannitol and Cr-EDTA) demonstrates a very sharp decrease in permeability as molecular size increases. The membrane behaves like a tight epithelium, with pores of of an approximate radius of 0.45 nm which allow but a poor passive diffusion. On the contrary, permeability to 3 methylglucose and 2 deoxyglucose is much too high for passive diffusion. Transfer competition between D-glucose and 3 methylglucose affords other evidence for a stereospecific monosaccharide carrier. The relationship between the presumably "active" sodium flux out of the fetus and the electrical potential difference across the placenta is discussed. The fetus is usually negative to the mother but the potential difference changes from day to day, and in twin gestation, the respective fetomaternal potentials seem to be independent. Acid infusion to the fetus increases the potential difference. The maintenance of this electrical or chemical gradients is taken as a consequence of the low passive permeability of the placenta.

Thermophilic methanogenesis in a hot-spring algal-bacterial mat (71 to 30 degrees C).

Algal-bacterial mats which grow in the effluent channels of alkaline hot springs provided an environment suitable for studying natural thermophilic methane producing bacteria. Methane was rapidly produced in cores taken from the meat and appeared to be an end product of decomposition of the algal-bacterial organic matter. Formaldehyde prevented production of methane. Initial methanogenic rate was lower and methanogenesis became exponential when samples were permitted to cool before laboratory incubation. Methanogenesis occurred and methanogenic bacteria were present over a range of 68 to 30 degrees C, with optimum methanogenesis near 45 degrees C. The temperature distribution of methanogenesis in the mat is discussed relative to published results on standing crop, primary production, and decomposition in the thermal gradient. The depth distribution of methanogenesis was similar to that of freshwater sediments, with a zone of intense methanogenesis near the mat surface. Methanogenesis in deeper mat layers was very low or undetectable despite large numbers of viable methanogenic bacteria and could not be stimulated by addition of anoxic source water, sulfide, or a macronutrient solution.

Long-acting oral vs injectable antipsychotic drugs in schizophrenics: a one-year double-blind comparison in multiple episode schizophrenics.

Sixty patients meeting the criteria established for schizophrenia who attained a clinical plateau following hospital discharge were randomized to receive for one year either penfluridol, 20 to 160 mg orally once each week, or fluphenazine decanoate, 0.5 to 4 ml every two weeks. The relapse rate for both treatments was low and equal. The rate of recurrence of psychosis for patients receiving penfluridol was 7% and for those receiving fluphenazine decanoate 10%. A retrospective comparison of the penfluridol group was made to a similar group of patients assigned to placebo in an earlier study. Placebo-treated patients had a relapse rate of 68%. Penfluridol patients had statistically fewer psychotic relapses. Questions about the possible carcinogenicity of penfluridol in animals will have to be resolved before it can be widely used. This study demonstrates the feasibility of using an oral, long-acting antipsychotic agent. It would be a useful psychopharmacologic addition in the treatment of outpatient schizophrenics.

Cold-induced vasodilatation response at different water bath temperatures in monkeys.

The response of cold-induced vasodilatation (CIVD) at different water bath temperatures was studied in 20 monkeys (3.5 kg) in a conscious state in a thermoneutral room. The animals were controlled by seating in a monkey chair, and the right hind limb up to 7.5 cm from the heel was immersed in a water bath for 60 min. Four series of experiments were conducted at water bath temperatures of 0 degrees, 4 degrees, 8 degrees, and 12 degrees C, respectively, at weekly intervals and the skin temperatures were measured from three sites in the foot. Marked CIVD response was noted from the dorsum and, to a lesser extent, from the sole of the foot, but no response was seen from the tip of the middle toe at 0 degrees, 4 degrees, and 8 degrees C water bath temperatures. The pattern of CIVD response at 4 degrees C was identical to that of 0 degrees C, but the response at 8 degrees C was poor and was absent at 12 degrees C. Three patterns of CIVD--such as hunting, proportional control, and slow, steady, and continuous rewarming--was observed. However, 15% of the animals did not exhibit any CIVD. The observations show that the CIVD response of monkeys is remarkably similar to that of man.

TRH-like immunoreactivity in urine, serum and extrahypothalamic brain: non-identity with synthetic pyroglu-hist-pro-NH2 (TRH).

TRH-like immunoreactive substances obtained from several areas of rat brain and from human serum and urine were chromatographically separated by TLC and the resulting immunoreactive 'elution profiles' compared with that obtained for pyroglu-hist-pro-NH2 (TRH). For hypothalamus and septal-preoptic samples TRH was present, but represented less than 100% of the immunoreactive substances. For cortex, amygdala, brain stem, serum and urine, no TRH was detectable in the immunoreactive substances from those samples. The implications of these findings in relation to 'TRH' distribution studies and validation of small peptide RIAs are discussed.

Species variability in plasma S-sulfonate levels during and following sulfite administration.

It has been shown that S-sulfonate compounds (R-S-SO-3) are produced by the action of sulfite on reactive disulfide bonds [4,5]. Plasma S-sulfonate production was determined as a function of sulfite ingestion and intraperitoneal injection in rats, mice and rhesus monkeys. The tendency of these species and of the rabbit [8] to produce S-sulfonates in plasma was related to the availability of sulfite and of reactive disulfide bonds and to the stability of plasma protein S-sulfonates. The rhesus monkey and the rabbit accumulated plasma S-sulfonates much more readily than did the rat, while the mouse produced little, if any, under the same test conditions. Plasma protein S-sulfonate fractions in the rat and rhesus monkey were characterized by half-lives of approximately 4 and 8 days respectively. The sensitivity and precision of the analytical method for plasma protein S-sulfonate were improved by incorporation of 35S into the outer sulfur atom of the S-sulfonate moiety (R-S-35SO-3).

Atypical expression of beta-galactosidase deficiency in a child with Hurler-like features but without neurological abnormalities.

A 28-month-old child was found to have several clinical features of lysosomal storage diseases, including: coarse facies, hepatosplenomegaly, lumbar kyphosis due to hypoplastic beaked L1 and L2 vertebral bodies, vacuolated lymphocytes in blood smears and rare foamy hystiocytes in bone marrow. However, no signs of neurological or ocular abnormalities were detected. A beta-galactosidase deficiency was demonstrated in leukocytes and cultured skin fibroblasts, with a residual activity toward 4-methylumbelliferyl-beta-galactopyranoside ranging between 5 and 15% of the normal mean. Normal activities were found for several other lysosomal acid hydrolases. beta-Galactosidase activities in leukocytes and cultured skin fibroblasts from both parents were within the normal ranges. The patient seems to represent an atypical expression of acid beta-galactosidase deficiency, since his clinical picture does not exaclty correspond to that of either the two classical types of GM1-gangliosidosis or other atypical patients reported in the literature havining beta-galactosidase deficiency.

Anticonvulsant action of a 1,5-benzodiazepine, clobazam, in reflex epilepsy.

Clobazam, an anxiolytic 1,5-benzodiazepine, has been evaluated as an anticonvulsant in 2 animal models. In mice showing sound induced seizures, clobazam, 1--4 mg/kg, i.p., blocked seizure responses for 1--2 hr. In Senegalese baboons Papio papio showing photically induced myoclonus or seizures, clobazam, 2--12 mg/kg, i.v., totally prevented such responses for up to 6 hr. In baboons pretreated with allylglycine, 170--185 mg/kg, a similar but briefer protection was induced by clobazam. Neurological toxicity was not prominent (transient, slight nystagmus after clobazam, 2--6 mg/kg; muscular hypotonia after clobazam, 12 mg/kg). The possibility that 1,5-benzodiazepines are superior to 1,4-benzodiazepines in the therapy of epilepsy requires clinical investigation.

Subcortical projections of the dorsomedial visual area (DM) of visual association cortex in the owl monkey, Aotus trivirgatus.

The efferent subcortical connections of the dorsomedial cortical visual area (DM) in the owl monkey were determined by tracing degenerating axons following lesions or by tracing axonal pathways following injection of radioactively labeled proline. Areas of termination included structures which are known to receive input from many other regions of cortex such as the claustrum, putamen, caudate nucleus, reticular nucleus of the thalamus and pontine nuclei. Other terminations were in subcortical structures which primarily receive input from visual area: these included the pregeniculate nucleus, the medial and central divisions of the inferior pulvinar nucleus, two loci in the superior pulvinar complex, the pretectum and the superior colliculus. Terminations were also seen in the lateral posterior nucleus, a part of the thalamus associated with the somatosensory system. These results further identify Area DM as an integral part of the visual system, suggest functional subdivisions of the pulvinar complex, and implicate the lateral posterior nucleus in the mediation of visual, as well as somatosensory, behavior.

Comparative studies of the ethynyl estrogens used in oral contraceptives. VI. Effects with and without progestational agents on carbohydrate metabolism in humans, baboons, and beagles.

Human subjects, baboons, and beagles were given cyclic regimens of ethynylestradiol or mestranol; after a number of such cycles, concurrent administration of norethindrone acetate, dl-norgestrel, or megestrol acetate was introduced for a similar number of cycles. Carbohydrate tolerance was evaluated by oral glucose tolerance testing in the human subjects and by intravenous glucose tolerance testing in the baboons and beagles. In the human subjects, neither mestranol nor ethynylestradiol at daily doses of 50 to 100 microgram/day produced any effect on fasting glucose levels or on glucose tolerance even after six cycles of treatment. The addition of the progestational compounds also had no effect on these two variables. In baboons, ethynylestradiol and mestranol were bioequivalent and produced a dose-related decrease in the glucose disposal rate. All three progestational agents counteracted this effect in a comparable manner. In beagles, on the other hand, estrogens produced an increase in the glucose disposal rate, and the addition of progestational agents produced an initial fall and a subsequent return to pretreatment levels.

Immunoreactive secretin in gastrointestinal mucosa of several mammalian species.

Immunoreactive secretin in hydrochloric acid extracts is relatively constant in the duodenum and proximal jejunum of pig and dog (3 microgram per g), but peaks in the distal duodenum of guinea pig (1 microgram per g), no secretin being detectable in the ileum of these species. Secretin is relatively constant throughout the small intestine of the rat and rabbit (0.4 to 0.1 microgram per g). Sephadex gel filtration patterns of all species and throughout the gastrointestinal mucosa revealed primarily a single peak with elution characteristics identical with that of purified or synthetic porcine secretin. The "big" secretin prominent in Boots secretin may be an alteration product perhaps attributable to chemicals used to stabilize the preparation. The "intermediate secretin" described by others has not been detected. It is concluded that in a variety of mammalian species most of the immunoreactive secretin extractable from the intestinal tract lies distal to the proximal duodenum and is not distinguishable from duodenal secretin in terms of molecular size.

Preliminary studies of plasma growth hormone releasing activity during medical therapy of acromegaly.

The in vitro growth hormone releasing activity of plasma obtained from six acromegalic subjects was measured before and during therapy. In five subjects, plasmas were obtained before and during successful medical therapy with medroxyprogesterone acetate (MPA). The sixth subject was sampled before and after transphenoidal Sr90-induced hypopituitarism. All subjects had a decrement in fasting growth hormone levels with respective therapies (29-88%). The in vitro growth hormone released from Rhesus monkey anterior pituitaries was assessed after incubating one lateral half in control plasma (pre-therapy) and the contralateral pituitary half in plasma obtained during or after therapy. Studies with plasmas obtained from the five patients successfully treated with MPA showed a decreased in growth hormone releasing activity during therapy in all (18-57%). Plasma obtained after Sr90 pituitary ablation in the sixth subject had 35% more growth hormone releasing activity than obtained before therapy. These results suggest that active acromegalics who respond to MPA with significantly lowered growth hormone levels may actually achieve this response because of a decrease in growth hormone releasing factor measured peripherally. The opposite response in one acromegalic subject, following Sr90 pituitary ablation and hypopituitarism, suggests that growth hormone releasing factor secretion may increase when growth hormone levels are lowered by ablative therapy.

Lip lesions in Nigerian Igbos.

Lesions of the lip seen over a 7-year period at a central laboratory serving the Igbos of Nigeria are reviewed. In approximately 8,500 surgical specimens, there were 63 jaw tumors but only 16 lip lesions. Two of lip lesions alone were carcinomas. Both were (a) squamous celled, (b) associated with sunlight-induced degeneration of the dermal collagen, and (c) found in young adult albinos. Accordingly, albinism should be recognized as one of the etiologic factors in lip cancer. The appropriate preventive action is the wearing of wide-brim hats by albinos.

Positive regulation of amidase synthesis in Pseudomonas aeruginosa.

Mutants of Pseudomonas aeruginosa were isolated that were acetamide-negative in growth phenotype at 41 degrees C and constitutive for amidase synthesis at 28 degrees C. Two mutants were derived from the magno-constitutive amidase mutant PAC111 (C11), and a third from a mutant that had enhanced inducibility by formamide, PAC153 (F6). The three temperature-sensitive mutants produced amidases with the same thermal stabilities as the wild-type enzyme. Cultures growing exponentially at 28 degrees C, synthesizing amidase constitutively, ceased amidase synthesis almost immediately on transfer to 41 degrees C. Cultures growing at 41 degrees C were transferred to 28 degrees C and had a lag of about 0.5 of a generation before amidase synthesis became detectable. Pulse-heating for 10 min at 45 degrees C of a culture growing exponentially at 28 degrees C resulted in a lag of about 0.5 of a generation before amidase synthesis recommenced after returning to 28 degrees C. Acetamide-negative mutants that were unable to synthesize amidase at any growth temperature were isolated from an inducible strain producing the mutant B amidase PAC398 (IB10). Two mutants were examined that gave revertants producing B amidase but with novel regulatory phenotypes. It is suggested that amidase synthesis is regulated by positive control exerted by gene amiR.

Spontaneous somatic mutations. Structural studies on mutant immunoglobulins.

The precise alterations in the protein amino acid sequences of the immunoglobulin heavy chains of spontaneously arisen MOPC 21 mutant clones IF2 and IF1 have been determined. All the cyanogen bromide fra-ments of both heavy chains have been isolated and compared to the wild type CNBr fragments. For IF2, there is an internal deletion, from the wild type sequence, of 96 amino acids, from residues 121 to 215 inclusive. Moreover, in IF2, there are no disulfide bonds formed between heavy and light chains, presumably because of the deletion of the CH1 pseudosubunit. There are no other alterations in its covalent structure. For IF1, there is a deletion of the COOH-terminal 83 amino acids (residues 358 to 440, inclusive). Although IF1 heavy chain behaves on dodecyl sulfate-polyacryl-amide gels as if it were only 10 to 15 residues shorter than wild type, no other amino acid sequence differences from wild type are found. IF1 arose most likely by a nonsense mutation of a serine codon. For IF2, whose deletion is like that seen in some human heavy chain disease proteins, the most likely explanation is an error of recombination. The structure of IF2 suggests that the heavy chain variable region ends at a position homologous to residue 120 of the MOPC 21 heavy chain.

Surface organization and composition of Euglena. II. Flagellar mastigonemes.

The surface of the Euglena flagellum is coated with about 30,000 fine filaments of two distinct types. The longer of these nontubular mastigonemes (about 3 micron) appear to be attached to the paraflagellar rod whereas the shorter nontubular mastigonemes (about 1.5 micron) are the centrifugally arranged portions of a larger complex, which consists of an attached unit parallel to and outside of the flagellar membrane. Units are arranged laternally in near registration and longitudinally overlap by one-half of a unit length. Rows of mastigoneme units are firmly attached to the axoneme microtubules or to the paraflagellar rod as evidenced by their persistence after removal of the flagellar membrane with neutral detergents. SDS-acrylamide gels of whole flagella revealed about 30 polypeptides, of which two gave strong positive staining with the periodic acid-Schiff (PAS) procedure. At least one of these two bands (glycoproteins) has been equated with the surface mastigonemes by parallel analysis of isolated and purified mastigonemes, particularly after phenol extraction. The faster moving glycoprotein has been selectively removed from whole flagella and from the mastigoneme fraction with low concentrations of neutral detergents at neutral or high pH. The larger glycoprotein was found to be polydisperse when electrophoresed through 1% agarose/SDS gels. Thin-layer chromatography of hydrolysates of whole flagella or of isolated mastigonemes has indicated that the major carbohydrate moiety is the pentose sugar, xylose, with possibly a small amount of glucose and an unknown minor component.

Visual-field displacements in human beings evoked by accoustical transients.

Sixty-two of 133 subjects reported visual-field displacements when they were exposed to intense (125 dB SPL) repetitive audiofrequency transients. This phenomenon was investigated in three experiments. Frequency (100-5000 Hz) was varied in experiment I; repetition rate (0.5/s--6.0/s) was varied in experiment II; acoustical transient onset/offset time (0.2--25 ms) was examined in experiment III. The results of these three experiments indicated that the largest proportion of displacement reports and the largest perceived motion magnitudes followed stimulation in the 500- to 1000-Hz frequency range at repetition rates of about 1/s. Response differences as a function of onset/offset time were erratic. The pattern of results obtained in this study, in conjunction with the results of previous investigations of acoustical vestibular stimulation, suggests that the visual-field displacments resulted from stimulation of the receptors of the vestibular system. These experiments may account for discrepancies in reports of infrasound-evoked eye movements. Finally, it is suggested that intense sound exposure may damage the vestibular receptors with or without concomitant damage to the auditory portion of the membranous labyrinth.

Characterization and genetic control of the immune response to synthetic polypeptide antigens of defined geometry.

Both humoral and cell-mediated immune responses to the synthetic helical hapten-carrier conjugate poly-Glu-Tyr-Lys(TNP)-(Glu-Tyr-Ala)5 were found to be linked to the major histocompatibility locus in mice and guinea pigs. The responder mouse strains (H-2d haplotype) showed a primary IgM response with an IgG component appearing after the secondary immunization. The antibody response was accompanied by a positive DTH reaction in responder strains. Nonresponder mice (H-2b or H-2k haplotypes) showed neither IgM nor IgG antibodies and the DTH reaction was negative. Administration of the antigen as a complex with an immunogenic carrier was not effective in inducing a response in nonresponder mice. In guinea pig studies, it was found that strain 2 animals were able to mount an antibody response against the TNP-hapten and a DTH response against the polypeptide backbone. Strain 13 animals gave no anti-TNP antibodies at the lower dose levels and DTH activity was entirely negative for all doses of immunizing antigen. Replacement of the TNP hapten by the arsanilazo dipeptide derivative, BOC-gly-ARA-tyrosine, converted the nonresponder strain 13 guinea pigs into complete responders showing antibody and DTH reactions to both the hapten and the polypeptide backbone.

Antibacterial functions of macrophages in experimental protein-calorie malnutrition. II. Cellular and humoral factors for chemotaxis, phagocytosis, and intracellular bactericidal activity.

Cellular and humoral aspects of the antibacterial activity of macrophages during experimental protein-calorie malnutrition were studied. There were no defects in chemotaxis or bactericidal activity of cells from protein-deficient animals, although phagocytosis-associated oxygen consumption and hexose monophosphate shunt activity were depressed. However, marked impairment of humoral chemotactic factors generated in the peritoneal cavity by glycogen injection and of heatlabile serum opsonins for Staphylococcus aureus, Escherichia coli, Salmonella typhimurium, and Salmonella enteritidis was found. The studies suggested that some macrophage antibacterial functions measured in vitro are not altered in experimental acute protein-calorie malnutrition, but that serum factors, presumably complement-derived, would limit their in vivo function. Thymic involution and lymphocyte depletion would further impair in vivo cellular immune reactions affected by macrophages. This model may therefore prove useful for the study of specific aspects of cellular immunity in malnourished hosts and of specific rehabilitation strategies.

Model for disseminated intravascular coagulation: bacterial sepsis in rhesus monkeys.

DIC is a hemorrhagic syndrome frequently encountered as a complication in severe gram-negative bacterial sepsis. An animal model for sepsis-associated DIC was developed in order to permit study of the appearance and development of this syndrome in relation to the entire disease process. Rhesus monkeys (4 to 6 kg) were infected by intravenous injection of 10(9) Salmonella typhimurium organisms and studied for a period of 7 to 10 days following infection. Ten of 23 infected monkeys developed petechial rash characteristic of DIC, which appeared on days 1 to 2 infection and lasted 4 to 5 days. In the group of monkeys developing rash, activation of coagulation was suggested by an 80% decrease in platelet count and 20% to 30% increases in PT and APTT. Fibrinolytic system activation was indicated by the appearance of FDP. Kinin system activation was evidenced by decreases in both prekallikrein nad kininogen. Changes in laboratory tests suggestive of subclinical DIC were also noted in infected monkeys which did not develop a rash. Pathologic evidence of DIC was obtained through observation of numerous fibrin thrombi in the kidneys of the only monkey which died in the course of infection. Occurrence of DIC in association with this experimental infection in rhesus monkeys was established on the basis of clinical, laboratory, and pathologic criteria. Expression of the syndrome on days 1 to 2 following infection correlated with the period of increasing bacteremia.

The role of H-2-linked genes in helper T-cell function. III. Expression of immune response genes for trinitrophenyl conjugates of poly-L(Tyr, Glu)-poly-D,L-Ala--poly-L-Lys in B cells and macrophages.

Using lymph node T cells from poly-L(Tyr,Glu)-poly-D,L-Ala--poly-L-Lys[(TG)-A--L]-primed animals and B cells from animals primed with trinitrophenylated (TNP) protein or lipopolysaccharide, we have obtained anti-TNP-(TG)-A--L direct plaque-forming responses in vitro. Response to this antigen was shown to be controlled by the H-2 haplotype of the animal studied. The strain distribution of in vitro response was very similar to that previously reported by others for in vivo secondary IgG responses to (TG)-A--L. We investigated the cell types expressing the Ir gene(s) for (TG)-A--L in our cultures. F1, high responder x low responder mice were primed with (TG)-A--L. Their T cells were active in stimulating anti-TNP-(TG)-A--L responses of high responder but not low responder B cells and macrophages (MPHI), even though both preparations of B cells and Mphi were obtained from mice congenic at H-2 with one of the parents of the F1. For three low responder strains tested, of the H-2h2, H-2k, and H-2f haplotypes, the anti-TNP-(TG)-A--L response of low responder B cells and Mphis in the presence of high responder, F1 T cells could not be improved by the addition of high responder, antigen-bearing Mphis to the cultures. In one strain of the H-2a haplotype, it was shown that neither the B cells nor Mphis could be functional in anti-TNP-(TG)-A--L responses. Our results therefore suggested the Ir genes for anti-TNP-(TG)-A--L responses were expressed at least in B cells in all the low responder strains we studied, and, in mice of the H-2a haplotype, in Mphis too.

In vivo distribution of carbon-11 phenytoin and its major metabolite, and their use in scintigraphic imaging.

Curie quantities (0.3--1.5 Ci) of H11CN were used in the synthesis of C-11-tagged phenytoin (C-11.DPH) and 5-(p-hydroxyphenyl)-5-phenylhydantoin (C-11.HPPH), using a modified Bücherer-Bergs reaction. The H11CN was produced from a mixture of 95% nitrogen and 5% hydrogen by a 45-min bombardment with 10-MeV protons at 10 muA. Following i.v. infusions of C-11 DPH (13.7 mg/kg at a rate of 29 mg/min) into the left femoral vein of Rhesus monkeys, DPH shows persistent concentration in the brain and liver fields. Extravascular administration shows significant retention at the site of administration. Intravenous bolus injection of [11C]-HPPH into a Rhesus monkey, at a dose of 6.4 mg/kg, resulted in localization of this compound in the liver, gallbladder, urinary bladder, and intestinal fields. Loss of activity from the liver region, with appearance of this activity in the intestinal field, suggests that [11C]-HPPH is secreted into the intestine via the bile. Further investigation is needed to study the potential of [11C]-DPH as a brain-scanning agent and [11C]-HPPH as a possible cholescintigraphic agent.

Effects of enteral and parenteral nutrition on appetite in monkeys.

Varied clinical observations of the presence of either hunger or anorexia during intragastric or intravenous alimentation have led to the current experiments. Nine rhesus monkeys (Macaca mulatta) were involved in studies of the long-term effects of enteral and parenteral nutrition on appetite as assessed by feeding behavior and gastric motility. The monkeys received either intragastric infusions of glucose or a complete liquid diet, or intravenous infusions of glucose or glucose/amino acid solutions. Oral intake was accurately adjusted to account for the calories administered by the intragastric route. Oral intake was also reduced in a calorically equivalent amount to account for the calories received during intravenous glucose. When glucose/amino acid solutions were administered parenterally, adjustments were less accurate, with resultant overeating and weight gain in some monkeys during parenteral nutrition, followed by prolonged suppression of appetite after cessation of the infusions. Further studies of the effects of varied compositions of parenteral nutrition, and varied methods of weaning from infusions, are indicated.

Fatigue-induced damage in glutaraldehyde-preserved heart valve tissue.

Glutaraldehyde-preserved porcine mitral leaflet tissue has been subjected to extended accelerated fatigue loading in Ringer's solution containing 0.15% glutaraldehyde. Five tissue test pieces were subjected to cyclic tensile stresses of 50 and 200 Gm. per square millimeter and to 300 million to 800 million accumulated fatigue cycles. Tissue disruption occurred in each of the fatigued test pieces. Tensile loading, apart from reducing the acuteness of the collagen waveform and thereby decreasing tissue compliance, does not contribute significantly to the disruption process nor its rate of occurrence. Compressive flexure occurring during the unloading half of the fatigue cycle, however, does induce damage in the tissue. Mechanisms involved in the disruptive processes have been identified by conducting simultaneous morphologic and stress/strain observations on both the fatigued and unfatigued tissues in their wet functional condition. This vulnerability of the preserved tissue to compressive flexure could well affect the long-term durability of the glutaraldehyde-preserved heterograft valve, and this possibility is discussed in relation to the clinical use of these valves.

Periodically interspersed repetitive sequences may govern higher-order DNA coiling in chromatin and chromosomes.

The interspersed periodic arrangement of repetitive and unique sequences in eukaryotic DNAs is proposed as the underlying molecular basis for higher-order DNA coiling in chromatin and mitotic chromosomes. It is assumed that (i) two types of interspersed repetitive sequences are distributed strictly periodically throughout the genome, splitting the single copy DNA into short and long periods respectively in such a pattern that each long period is composed of a definite number of short periods and repeats, (ii) the short and long periods make the turn lengths of the solenoid and supersolenoid structures respectively determining their diameters; (iii) specific proteins interact with each type of repeats making cross ties between nearby repeats of each class helping to form, constrain, and stabilize the solenoid and the supersolenoid structures: (iv) the long period may be equated with the basic chromomere unit. The model predicts: (i) splitting of contiguous genes by inserted repetitive sequences; and (ii) two types of genomes differing in the hierarchy of DNA coiling.

Validation of a new technique for measurement of intracranial pressure with a scintillation counter.

Intracranial pressure sensors and subdural and subgaleal sensing tambours were used to measure the pressure difference between the intracranial and subgaleal spaces in two monkeys. The pressure differential was transmitted to fluid bathing a piston, to which an isotope source (145Pm) was attached. The radiation signal emanating through a fixed collimator was detected transcutaneously by a sodium iodide crystal contained within a photomultiplier tube connected to a scintillation counter. After in vitro testing of linearity, in vivo infusion studies were performed. Linearity between intracisternal pressure and radioactivity (r = 0.99; p less than 0.001) was established in the two experimental animals for an interval of 5 months and 1 year, respectively. Autopsy findings confirmed that the sensing tambours became encapsulated with a pseudomembrane that did not attenuate the pressure signal. The results of this investigation suggest that this method for measurement of intracranial pressure without transcutaneous connections may be suitable for long term monitoring of intracranial pressure.

Studies on the occurrence of Peptococcus indolicus and Corynebacterium pyogenes in abscesses in swine, and on the occurrence of Pc. indolicus in apparently normal skin and mucous membranes of piglets.

Pc. indolicus was isolated from 42.7% and Cb. pyogenes from 48.7% of 150 pus-samples from abscesses in pigs (slaughter-house material, Table I). In 41 specimens the two organisms were found together. Further, Pc. indolicus was demonstrated in 22.4% of 290 swabs from apparently normal skin and mucous membranes of piglets (autopsy material, Table II). By gel diffusion analysis the strains of Pc. indolicus were referred to the serotypes B, C, D, E, or F. The type distribution (Table III) possibly reflects a type-related variation in the invasive properties of Pc. indolicus.

Methodological problems in the measurement of drug-induced rotational behaviour: continuous recording reveals time-course differences undetected by previous techniques.

Rats were lesioned unilaterally in the medial forebrain bundle with either the catecholamine neurotoxin 6-hydroxydopamine or the indoleamine neurotoxin 5,6-dihydroxytryptamine. Their rotational responses in automated rotameters to a challenge with the dopamine-receptor agonist apomorphine were compared using four different techniques in current use, and by assessment of complete rotation curves using both conventional statistical procedures and elementary computer-derived elements of curvature. The rotational responses of the two groups, characterized neurochemically by identical depletions of striatal dopamine but with a greater depletion of striatal 5-hydroxytryptamine in 5,6-dihydroxytryptamine-lesioned animals, were indistinguishable using each of the four current techniques. Assessment of rotation curves by both methods revealed significant differences between the two groups, characterised by faster onset and offset of the rotational response in 5,6-dihydroxytryptamine-lesioned animals. Some current techniques may implicitly exclude the detection of such time-course differences in rotational behaviour. Assessment of complete rotation curves may best allow valid comparisons between experimental groups.

Effects of chronic lead exposure on levels of acetylcholine and choline and on acetylcholine turnover rate in rat brain areas in vivo.

Rats were exposed to lead acetate from birth, and were killed at the age of 44--51 days for analysis of levels and turnover rates of acetylcholine (ACh). Steady-state levels of ACh were not altered in midbrain, cortex, hippocampus, or striatum of lead-exposed rats. Similarly, no changes in choline (Ch) concentrations were found in cortex, hippocampus, or striatum. In the midbrain, however, a 30% reduction in Ch levels was observed. Changes in specific activity of Ch and ACh were measured as a function of time in selected brain areas of rats infused with a radio-labeled precursor of Ch. Specific activities of ACh were not altered. Ch specific activities were, however, significantly elevated in all brain areas examined, as compared with age-matched control rats. The in vivo ACh turnover rate in cortex, hippocampus, and striatum was diminished by 35%, 54%, 51%, and 33%, respectively. These findings provide direct evidence for an inhibitory effect of lead exposure from birth on central cholinergic function in vivo. Since a significant reduction of body weight was found in those animals treated with lead acetate, the alteration of central cholinergic function may partially be attributed to malnutrition observed in the lead-exposed animals.

Normal values for free light chains in serum different age groups.

The concentration of free light chains from the immunoglobulins was measured in twelve paired sera from mothers and newborns and from 149 sera from normal individuals in various age groups. Variations in concentration during life are correlated to the variations in the concentration of 'regular' immunoglobulins. A concentration of light chains in cord blood of 35% of mean normal adult level (MNA) together with a rapid passage of light chains across the placenta is interpreted as indicating catabolization of maternal light chains in the fetus. This is further supported by the finding of a lower concentration of light chains in maternal serum than in normal adult serum. The investigation shows that the concentration of light chains falls rapidly from 35 to 24% of MNA during the first few days of life. From the first week of life the concentration of light chains increases and low normal adult values are attained by one year of age. Except for difference in concentration, the elution pattern for light chains from Sephadex G-100 columns was similar for normal, adult and cord blood. The relationship between kappa and lambda chains--the K/L ratio--is 1.2 for normal and maternal serum and 1.0 for cord serum.

Experimental spinal cord trauma, II: Blood flow, tissue oxygen, evoked potentials in both paretic and plegic monkeys.

Graded clinical motor deficits were produced in a series of Rhesus monkeys subjected to experimental spinal cord trauma from a variety of impact loads. An argon washout technique was used to measure spinal cord blood flow; tissue oxygen carbon dioxide, and somatosensory evoked potentials (SEPs) were also monitored. Each animal received a clinical grade and, after a week of study, the spinal cords were removed for histopathological grading. Blood flow in paraplegic animals was significantly decreased at two hours and seven days following injury (5 ml/min/100 gms tissue); paraparetic animals showed no significant difference from preinjury levels (14 ml/min/100 gms tissue). Animals which completely recovered demonstrated increased flow (27 ml/min/100 gms tissue). Composite tissue oxygen was generally depressed in paraplegic animals (28 mm Hg/kg) but showed no clear pattern in other groups. Only 8% of monkeys rendered paraplegic preserved a somatosensory evoked potential (SEP) at five minutes after injury. Paraparetic animals were more likely (40%) to show initial preservation of the SEP and in normal animals, the SEP always returned by three hours. Histopathological grading tended to parallel clinical grading in 92% of the cases. Although the extremes of possible postinjury deficits (complete paraplegia or recovery) can be predicted from a combination of these measurements, incomplete lesions (whether judged clinically or pathologically) present a more variable picture.

The unique characteristics of covalently polymerized bovine serum albumin solutions when used as antibody detection media.

Bovine Serum Albumin solutions (BSA) have been chemically polymerized to give solutions (PBSA) with superior serological properties. The new PBSA reagents are shown to contain covalently bonded dimers, trimers, tetramers, and larger polymers, the presence of which is directly related to hemagglutination by IgG antibody. Data are presented which show that reagents containing increased amounts of higher molecular weight polymers enhance hemagglutination, as demonstrated by serum albumin titrations of various antisera. Additionally, isolated polymers are shown to enhance hemagglutination as a function of their molecular weight with the high molecular weight tetramers being more effective than the trimeric form, which in turn is more effective than the dimeric and monomeric forms. The protein concentration does not play any significant role in these events. The data establish that the polymeric content of bovine serum albumin reagents is a major factor in the potentiating properties of such solutions. Additionally, it is shown that these reagents act not only on the second stage of hemagglutination as a function of the bovine albumin present, but also on the first stage of hemagglutination as a function of the ionic strength of these reagents. The polymeric content and ionic strength of albumin solutions are the major criteria in determining the effectiveness of these potentiating reagents.

Bovine cryptosporidiosis: a transmission and scanning electron microscopic study of some stages in the life cycle and of the host-parasite relationship.

Transmission and scanning electron microscopy of the ileal mucosae from 12 calves infected with Cryptosporidium sp. showed cryptosporidia free in the lumen and attached to epithelium. The attached parasites were interpreted to be extracellular and adherent to the microvillous border of epithelial cells. Stages of the organism included crescentic-free merozoites, trophozoites, schizonts, gametes and oocysts. Attached parasites were detected chiefly at villous tips and all stages were present on a single villus. Attachment sites were characterized by absence or disintegration of microvilli, disorganization of the terminal web and development of a specialized attachment zone. There were increased numbers of lysosomes and irregularities in the nuclear membrane of parasitized epithelial cells. It was concluded that cryptosporidia exist in bovine intestine as extracellular parasites and cause epithelial changes that in turn probably cause or contribute to diarrheal disease.

Ultrastructure of human dermal blood vessels with special reference to the endothelial filaments.

The ultrastructure of endothelial cytoplasmic filaments of small blood vessels from the human dermis has been described. The material consisted of biopsies from normal abdominal and thoracic skin and also from the skin of patients with urticaria pigmentosa. Most vessels were surrounded by multiple layers of basal lamina and corresponded to the small venules of the subpapillary dermis. The wall of many vessels was composed by endothelial cells with clear cytoplasm which was rich in filaments and by endothelial cells with a dense cytoplasm which was poor in filaments. Some vessels had walls composed of clear endothelial cells only. The filaments varied in diameter between 80-120 A. Curling, recoiling and whorling of cytoplasmic filaments were obvious in endothelial cells of contracted vessels. Bulging of endothelial nuclei and nuclear indentations were seen in the skin lesion of urticaria pigmentosa. The possibility that the clear endothelial cells which are rich in filaments may be more actively involved in contraction than the dense cells, is discussed.

[Changes in several important metabolic parameters and insulin level during a 7-day total parenteral nutrition under pre- and postoperative conditions].

After the 24 hours preoperative infusion period 0.37% glucose, 0.05% fructose and 1.28% xylitol of the infused amount were excreted in the urine. Postoperatively fructose was the best metabolized energy donator before xylitol and glucose. As a sign of an undisturbed hepatic synthesis of lipoproteins the triglycerides rose up to the 5th postoperative day. During the parenteral nutrition and the additional surgical intervention the cholesterol fell from 192.3 to 128.5 mg/100 ml on the first postoperative day. The infusion solutions caused a rise of the insulin concentration from 23.2 to 46.3 U/l on the operation day. There is a positive nitrogen balance of 3.5 g/24 h on the operation day. The slight negative balance of - 1.15 g/24 h on the first postoperative day is reduced to - 0.61 g/24 h on the postoperative day. The changes of the enzymes LDH, GOT and AP were at normal range. The postoperative changes were due to the surgical intervention. Without a simultaneous change of enzymes, 5 patients had a rise of bilirubin up to 1.1 mg/100 ml. To avoid a too great loose of phosphate during a long-term parenteral nutrition period, it is important to put up a balance.

Insulin antibodies in the serum of diabetic children treated from the diagnosis of the disease with highly purified insulins.

Fifty-one diabetic children, treated with highly purified, porcine insulins from the diagnosis of the disease were studied for the development of insulin antibodies during the first years of treatment. Sera were obtained before the start of treatment and at repeated intervals thereafter. Serum insulin antibodies were measured by three methods in three laboratories. Twenty-nine children were treated with R.I. (rare immunogenic) insulins at one department and 22 with MC (monocomponent) insulins at the other department. Before the start of treatment, serum insulin antibodies were almost invariably zero or below the limit of detection. During the first year a considerable number of cases, more than that reported for adults, formed detectable amounts of antibodies, and more so in the R.I. than in the MC series. The levels were however definitely lower than those observed with the same methods in diabetic children on conventional insulins. Analysis of variance showed no differences between the various age groups. No significant correlation was found between the highest titre of serum insulin antibodies on the one hand and insulin dose or glucosuria on the other hand. The results confirm the concept that children form antibodies to insulin more actively than adults.

Differential diagnosis of pelvic masses by gray scale sonography.

An approach to the sonographic differential diagnosis of pelvic masses based on their size, location, internal consistency, and definition of borders is presented. Diagnostic schemes were derived from correlating the sonographic features with histomorphology in 170 surgically proven pelvic masses. Besides separating pelvic masses into the conventional categories of cystic, complex, and solid, gray scale sonographic features of a pelvic mass can be used to subcategorize these masses into a more useful differential diagnoses. Although the features seen on a sonographic image were specific in only two types of pelvic masses (pattern specificity greater than 85%), the sonographic information can be effectively utilized for establishing differential diagnoses of pelvic masses. Among the various sonographic patterns observed, homogenously cystic adnexal masses were the least specific pattern, whereas a predominantly cystic, extrauterine mass with internal septation was highly specific for a pseudomucinous cystadenoma. Several pelvic masses such as dermoid cysts demonstrated more than one sonographic appearance and, therefore, had to be considered in more than one diagnostic category.

Afterload reduction and cardiac performance. Physiologic basis of systemic vasodilators as a new approach in treatment of congestive heart failure.

Digitalis and diuretics constitute conventional therapy of congestive heart failure, but systemic vasodilators offer an innovative approach in acute and chronic heart failure of decreasing increased left ventricular systolic wall tension (ventricular afterload) by reducing aortic impedance and/or by reducing cardiac venous return. Thus, vasodilators increase cardiac output (CO) by diminishing peripheral vascular resistance (PVR) and/or decrease increased left ventricular end-diastolic pressure (LVEDP) (ventricular preload) by diminishing venous tone. Concomitantly, there is reduction of myocardial oxygen demand, thereby reliably reducing angina pectoris in coronary disease, and potentially limiting infarct size and ischemia provided systemic arterial pressure remains normal. The vasodilators produce disparate modifications of cardiac function depending upon their differing alterations of preload versus impedance: nitrates principally cause venodilation (decrease LVEDP); nitroprusside, phentolamine and prazosin produce balanced arterial and venous dilation (decrease LVEDP and increase CO) provided left ventricular filling pressure is maintained at the upper limit of normal; whereas hydralazine predominantly effects arteriolar dilation (increases CO). With depressed CO plus highly increased LVEDP and increased PVR, nitrates also induce some increase of CO by reducing PVR. Combined nitroprusside and dopamine synergistically enhance CO and decrease LVEDP. Mechanical counterpulsation aids nitroprusside in acute myocardial infarction. The 30-minute venodilator action of sublingual nitroglycerin is extended for 4 to 6 hours by cutaneous nitroglycerin ointment, by sublingual and oral isosorbide dintrate, and by oral pentaerythritol tetranitrate and sustained-release nitroglycerin capsules. Ambulatory oral vasodilator therapy is provided by long-acting nitrates (relieve pulmonary congestion); hydralazine (improves fatigue); prazosin alone, combined nitrate-hydralazine combined prazosin-hydralazine (improve both dyspnea and fatigue).

Fibrinogen turnover in pregnant rabbits during the first and last thirds of gestation.

Although thrombin-mediated fibrinogen derivatives have been observed in normal pregnancy, an increased turnover of fibrinogen has been suspected but has not yet been demonstrated. Fibrinogen turnover was studied in 14 pregnant and 10 nonpregnant female rabbits by use of purified rabbit 125I-labeled fibrinogen. In the last third of gestation the half life of fibrinogen was shortened by 45% and the fractional catabolic rate increased by 44% in comparison to the values for the first third of gestation obtained in the same rabbits. The distribution volume of the injected fibrinogen representing the plasma volume increased by a mean of 18% during gestation. Fibrinogen concentration did not change during gestation. From a comparison of the measured data from the first and last thirds of gestation, it can be calculated that the synthesis rate of fibrinogen increased by about 80%. Furthermore, a positive correlation was found between the number of young per litter and the acceleration of fibrinogen elimination, indicating that a local process of intravascular coagulation in the placenta is responsible for the accelerated turnover of fibrinogen during gestation.

The fate of intraportally transplanted islets in diabetic rats. A morphologic and immunohistochemical study.

Streptozotocin-induced diabetes in the rat can be reversed by the transplantation of isogenic islets of Langerhans from neonatal donors. We studied the morphology of intraportally transplanted islets with the aid of the immunoperoxidase staining technique to identify insulin-, glucagon-, somatostatin-, and pancreatic polypeptide-containing cells at 24 hours, 48 hours, 1 week, 2 weeks, 4 weeks, 39 weeks, and 65 weeks after transplant. Embolized pancreatic tissue, composed of approximately 80% acini and 20% islets, is initially distributed throughout the liver mainly to terminal branches of the portal system. Endothelialization and organization occur rapidly with the smaller fragments and within the first 4 weeks for larger thrombi. Exocrine pancreatic elements largely disappear as islet cells move into the hepatic lobules from the portal spaces. At 65 weeks after transplant, all islet cell types can be identified within large complex islet structures. The results of this study establish the survival and continued function of all known rat pancreatic islet cell types long after transplantation and support the theory that islet transplantation may represent the most physiologic replacement of hormonal deficiencies in the diabetic recipient.

Plasmodium falciparum and Plasmodium vivax infections in the owl monkey (Aotus trivirgatus). II. Responses to chloroquine, quinine, and pyrimethamine.

The studies described in this report were designed to determine the responses of established infections with eight strains of Plasmodium falciparum and two strains of P. vivax in owl monkeys to treatment with chloroquine, quinine, and pyrimethamine. Responses with these different strains ranged from cure via application of well-tolerated doses of two of the above drugs and refractoriness to treatment with maximally tolerated doses of the third, to complete resistance to maximally tolerated doses of all three compounds. The results of treatment exhibited in infected owl monkeys correlated well in two respects with those reported in humans infected with the same plasmodial species. First, calculated on a milligram per M2 basis, the doses of chloroquine, quinine, or pyrimethamine required for a CD90 response in owl monkeys infected with strains susceptible to these drugs were remarkably similar to the doses required and/or employed for cure of infections with so-called drug-susceptible strains in human patients. Secondly, with few exceptions, the responses to the above drugs in owl monkeys infected with the ten specially selected strains were essentially identical with those exhibited by human volunteers or patients infected with the same strains. Together, these findings and correlations provide strong support for use of owl monkeys infected with appropriate strains of P. falciparum and P. vivax in the search for more broadly effective antimalarial drugs.

Ectopic ossification after hip arthroplasty.

The incidence of radiographically visible ectopic ossification around the hip joint was redorded in 145 hip joints of 132 patients treated by endoprosthetic replacement. There were 56 total hip replacements with a McKee-Farrar and 39 with a Brunswik type of endoprosthesis; in a further 50 hips the femoral head was replaced with a Moore or Thompson prosthesis. An identical antero-lateral surgical approach was used in all, without detachment of the greater torchanter. The patients were re-examined 3, 6, and12 months after the operation. The extent of ectopic ossification was graded from 0 to III and correlated with pain and with the function and mobility of the operated hip. Ectopic ossification of varied extent was recorded in 37 % after total hip replacement and in 38 % after replacement of the femoral head. Of these ossifications 95 % were recognizable within 3 months; they did not increase in size, but often in density during the following months. One case of bony ankylosis was noted. Ectopic ossification of slight (grade I) to moderate (grade II) degree did not cause pain or affect the function of the operated hip, but reduced the mobility of the affected hip. The difference in mobility between grade I and grade II was significant (p less than 0.05), and between grade 0 and grade II highly significant (p less than 0.001).

Action of the "nude" gene on pigmentation of the coat in c57 black and c3 mice.

The authors have studied pigmentary changes of skin and hair due to the presence of the "nude" gene in pigmented species (C 57 Bl. 6J, C3H). Morphological (histology, electron microscopy) and biochemical (polyacrylamide gel electrophoresis of tyrosinase activities) studies showed that the pigmentary alterations of the "nude" mice were related to hair cycle and hair growth wave pattern. In fact, in the "nude" mice the hair follicles evolves cyclically similarly to mice of normal coat. In depigmented skin, the hair follicles were in the resting phase and no soluble tyrosinase could be demonstrated.

Amino acid derangements in patients with sepsis: treatment with branched chain amino acid rich infusions.

Sepsis is a major catabolic insult resulting in modifications in carbohydrate and fat energy metabolism, and leading to increased muscle breakdown and nitrogen loss. Insulin resistance, which develops in sepsis, decreases glucose utilization, but plasma insulin levels are sufficiently elevated to prevent lipolysis, resulting in a further energy deficit. The availability of fuels in sepsis is therefore limited, and the body resorts to muscle breakdown, gluconeogenesis, and amino acid oxidation for energy supply. Previous work has not defined, however, the exact alterations in amino acid metabolism. Therefore, the following studies were undertaken. Blood samples were drawn from fifteen patients in whom the diagnosis of sepsis was clinically established; the samples were analyzed for amino acid, beta-hydroxyphenylethanolamines, glucose, insulin and glucagon concentrations. The plasma amino acid pattern observed was characterized by an increase in total amino acid content, due mainly to high levels of the aromatic amino acids (phenylalanine and tyrosine) and the sulfur-containing amino acids (taurine, cystine and methionine). Alanine, aspartic acid, glutamic acid and proline were also elevated, but to a lesser degree. The branched chain amino acids (valine, leucine and isoleucine) were within normal limits, as were glycine, serine, threonine, lysine, histidine and tryptophan. Those patients who did not survive sepsis had higher levels of aromatic and sulfur-containing amino acids as compared to those patients surviving sepsis. On the other hand, those patients surviving sepsis had higher levels of alanine and the branched chain amino acids. In a second group of five patients with overwhelming sepsis accompanied by a state of metabolic encephalopathy, a parenteral nutrition solution consisting of 23% dextrose, and an amino acid formulation enriched with branched chain amino acids was administered. In these five patients, normalization of the plasma amino acid pattern and reversal of encephalopathy was observed. The following sequence of events may be postulated: The septic patient develops insulin resistance in the peripheral tissues, primarily muscle, while the adipose tissue is much less affected. The insulin resistance and the inability to utilize fat leads to increased muscle proteolysis. Muscle breakdown results in release into the blood of enormous amounts of various amino acids; the muscle itself is able to oxidize the branched chain amino acids, supplying the muscles' own energy requirements and alanine for gluconeogenesis. The extensive muscle proteolysis coupled with relative hepatic insufficiency occurring early in sepsis results in the appearance in the plasma of high levels of most of the amino acids present in muscle, particularly the aromatic and the sulfur-containing amino acids. The outcome of patients with sepsis might be positively affected by combined therapy with glucose, insulin and branched chain amino acids.

Breast biopsy. A comparison of outpatient and inpatient experience.

Nine hundred ninety-seven breast biopsies that were performed at one hospital over the five-year period from 1971 through 1975 were reviewed because of a changing pattern in the use of breast biopsies on outpatients who were under local anesthesia. In 1971, 17% of all breast biopsies were performed as outpatient procedures; by 1975, the figure was 60%. In 1971, 5% of all malignant neoplasms were diagnosed by the use of biopsies as outpatient procedures and 30% in 1975. Hospital charges for biopsy on an inpatient basis of benign breast disease were 7.2 times higher than for biopsy on an outpatient basis. Interviews of 102 patients clearly suggested that most patients were satisfied with the outpatient breast biopsy experience. Outpatient breast biopsy under local anesthesia is a safe procedure that is more economical in terms of medical cost, surgeons' time, and patients' time away from home and/or job. Preliminary biopsy of malignant lesions using local anesthesia permits more efficient use of diagnostic procedures to stage the extent of disease prior to treatment. Patient acceptance of breast biopsy as an outpatient procedure under local anesthesia was similar to their acceptance of biopsy on an inpatient basis under general anesthesia.

Comparative studies on two ferredoxins from the cyanobacterium Nostoc strain MAC.

Two ferredoxins were isolated from the cyanobacterium Nostoc strain MAC grown autotrophically in the light or heterotrophically in the dark. In either case approximately three times as much ferredoxin I as ferredoxin II was obtained. Both ferredoxins had absorption maxima at 276, 282 (shoulder), 330, 423 and 465 nm in the oxidized state, and each possessed a single 2 Fe-2S active centre. Their isoelectric points were approx. 3.2. The midpoint redox potentials of the ferredoxins differed markedly; that of ferredoxin I was --350mV and that of ferredoxin II was --445mV, at pH 8.0. The midpoint potential of ferredoxin II was unusual in being pH dependent. Ferredoxin I was most active in supporting NADP+ photoreduction by chloroplasts, whereas ferredoxin II was somewhat more active in pyruvate decarboxylation by the phosphoroclastic system of Clostridum pasteurianum. Though the molecular weights of the ferredoxins determined by ultracentrifugation were the same within experimetnal error, the amino acid compositions showed marked differences. The N-terminal amino acid sequences of ferredoxins I and II were determined by means of an automatic sequencer. There are 11--12 differences between the sequences of the first 32 residues. It appears that the two ferredoxins have evolved separately to fulfil different roles in the organism.

[Solitary mastocytoma].

A case is reported of a four--month--old male infant with mastocytoma localized on antero--internal side of left leg. It was a single lesion seen since birth, of tumoral aspect, about 3.5 x 2 x 0.8 cms., light brown color. The pathologic study confirmed the diagnosis. The course was uneventful and disappeared spontaneouly in one year.

In vitro evaluation of some derivatives of the carcinogen Butter Yellow: implications for environmental screening.

The rat-liver carcinogen 4-dimethylaminoazobenzene (Butter Yellow, DAB) and 12 of its structural analogues have been evaluated in a cell transformation assay. Eight of these analogues have already been tested for carcinogenicity in rats, whilst the remaining 4 are new or hitherto untested. Benzidine and its 3,3'-disulphonic acid derivative have also been evaluated. The in vitro results agree with long-term animal data for 8 compounds but disagree in finding DAB-4'-sulphonic acid, 4-trifluoromethyl-DAB and 4-diethylaminoazo-benzene positive. Possible reasons for these divergencies are discussed. It is concluded that 9-phenylazojulolidine and N-methyl-5-phenylazoindoline have carcinogenic potential and that 3,5-dimethyl-4-aminoazobenzene and 4-aminoazobenzene-4'-sulphonic acid are likely to prove non-carcinogenic. Addition of azobenzene to the in vitro assay medium increases the transforming potency of DAB 25-fold. It is suggested that it acts as a competitive substrate for one of the enzymes that detoxify DAB, and that this effect is related to that produced by norharman. Sulphonic-acid derivatives of established carcinogens are usually inactive. The basis of this effect has been investigated, and it is suggested that it can operate by two separate mechanisms. It has been established that this assay cannot be relied upon to predict the in vivo potency of a carcinogen. Consideration has been given to possible changes which could be made to the liver activation system (the S-9 mix) currently used in in vitro carcinogenicity assays, and a diagram is presented of the metabolic conversions of a compound which might lead to mutation or tumour formation. This enables the term potential carcinogen to be accurately defined, and indicates a possible difference between absolute non-carcinogens and compounds which fail to produce cancer in vivo.

Use of fluorescence polarization to monitor intracellular membrane changes during temperature acclimation. Correlation with lipid compositional and ultrastructural changes.

Fluorescence polarization of 1,6-diphenylhexatriene (DPH) was used to study the effects of temperature acclimation on Tetrahymena membranes. The physical properties of membrane lipids were found to be highly dependent on cellular growth temperature. DPH polarization in lipids from three different membrane fractions correlated well with earlier freeze-fracture and electron spin resonance observations showing that membrane fluidity progressively decreases in the order microsomes greater than pellicles greater than cilia throughout a wide range of growth temperatures. Changes in membrane lipid fluidity following a shift from high to low growth temperatures proceed rapidly in the microsomes, whereas there is a pronounced lag in the changes of peripheral cell membrane lipids. These data support previous observations that adaptive changes in membrane fluidity proceed via lipid modifications in the endoplasmic reticulum, followed by dissemination of lipid components to other cell membranes. The rapid changes in polarization observed in the microsomal lipids following a temperature shift correspond closely with the time-dependent alterations in both lipid fatty acid composition and freeze-fracture patterns of membrane particle distribution, suggesting that, in the endoplasmic reticulum, lipid phase separation is the primary cause of membrane particle rearrangements.

The mechanism of reduction of the ubiquinone pool in photosynthetic bacteria at different redox potentials.

(1) A flash number dependency of flash-induced absorbance changes was observed with whole cells of Rhodospirillum rubrum and chromatophores of R. rubrum and Rhodopseudomonas sphaeroides wild type and the G1C mutant. The oscillatory behavior was dependent on the redox potential; it was observed under oxidizing conditions only. Absorbance difference spectra measured after each flash in the 275--500 nm wavelength region showed that a molecule of ubiquinone, R, is reduced to the semiquinone (R-) after odd-numbered flashes and reoxidized after even-numbered flashes. The amount of R reduced was approximately one molecule per reaction center. (2) The flash number dependency of the electrochromic shift of the carotenoid spectrum was studied with chromatophores of Rps. sphaeroides wild type and the G1C mutant. At higher values of the ambient redox potential a relatively slow phase with a rise time of 30 ms was observed after even-numbered flashes, in addition to the fast phase (completed within 0.2 ms) occurring after each flash. Evidence was obtained that the slow phase represents the formation of an additional membrane potential during a dark reaction that occurs after flashes with an even number. This reaction is inhibited by antimycin A, whereas the oscillations of the R/R- absorbance changes remain unaffected. At low potentials (E = 100 mV) no oscillations of the carotenoid shift were observed: a fast phase was followed by a slow phase (antimycin-sensitive) with a half-time of 3 ms after each flash. (3) The results are discussed in terms of a model for the cyclic electron flow as described by Prince and Dutton (Prince, R.C. and Dutton, P.L. (1976) Bacterial Photosynthesis Conference, Brussels, Belgium, September 6--9, Abstr. TB4) employing the so-called Q-cycle.

Studies on the stability of immobilized xanthine oxidase and urate oxidase.

The stability of immobilized preparations of xanthine oxidase and urate oxidase was studied, and optimized, because of the potential joint use of both enzymes in clinical analysis. Xanthine oxidase was immobilized on cellulose, Sepharose, hornblende, Enzacryl-TIO, and porous glass. Thehalf-lives of these preparations at 30 degree C ranged from 40 min to 5.0 hr. In this respect immobilized enzyme resembled soluble enzyme in dilute solution (0.11 mg/ml), when the half-live was about 3.5 hr. More concentrated enzyme solution (1 mg/ml) had a half-life of 64 hr, and was, therefore, considerably more stable than the untreated immobilized xanthine oxidase preparations. Inclusion of albumen in storage and assay buffer increased the half-life of bound xanthine oxidase. So also did treatment with glutaraldehyde: in the case of xanthine oxidase bound to Enzarcyl-TIO such treatment increased the half-life at 30 degree C from 3 hr to about 100 hr. Immobilized xanthine dehydrogenase was more stable than immobilized xanthine oxidase: the dehydrogenase lost no activity during continuous assay for 5 hr at 30 degree C. The stability of immobilized urate oxidase depended on the quantity of enzyme used and on the time of stirring during immobilization: thus a preparation was made (by stirring urate oxidase (48 mg/g support) with Enzacryl-TIO for 24 hr) which lost no activity during 350 hr at 30 degree C.

Selective amplitude histograms: a statistical approach to EEG-single unit relationships in generalized epilepsy.

Statistical analysis techniques that permit detection and quantification of EEG-single unit correlations were employed in a study of generalized penicillin epilepsy in the cat. Single unit activity was recorded in cerebral and cerebellar cortices and compared to the locally recorded EEG. It was found that during generalized paroxysmal activity the background EEG was significantly related to the time of occurrence of unit discharge. The degree of synchrony of various units differed but tended to increase as the duration and extent of paroxysmal activity increased. These relationships were usually not evident upon visual inspection of the original unprocessed data but were consistently detected by the analysis techniques described here. The results demonstrate the usefulness of a statistical approach to the analysis of single unit data and suggest that, not only is there a significant relationship between paroxysmal events and neuronal activity in generalized penicillin epilepsy, but also an overall trend to closer synchronization of EEG and single unit discharges during nonparoxysmal periods.

Current management of unstable angina.

The patient with unstable angina (angina of recent onset, of changing pattern or occurring at rest) is at high risk of myocardial infarction and sudden death. Patients with simple angina of recent onset can generally be managed out of hospital. Those with progressive angina or angina at rest should be admitted to a coronary care unit, kept at bed-rest, and given propranolol and long-acting nitrates when such therapy is indicated. With these approaches the rate of infarction within 1 to 3 months after the onset of unstable angina is about 12% (as compared with 40% before 1970); the mortality in the same period is less than 2% (as compared with 17% before 1970), though during the first year it is about 17%, much higher than in patients with stable angina and in survivors of acute myocardial infarction.Urgent aortocoronary bypass grafting has proven to be unnecessary and probably undesirable for most patients with unstable angina, and is now generally reserved for patients who continue to have angina in hospital while receiving full medical therapy. The ongoing management of patients whose angina is controlled during the acute phase remains controversial. The main options are to operate on every possible patient, to operate only on those with certain distributions of coronary artery lesions, and to operate only on those who have recurrent symptoms. Further studies are required to delineate the etiology and the Optimal management of unstable angina.

Concurrent depression of tumor macrophage infiltration and systemic inflammation by progressive cancer growth.

Macrophage accumulation during the growth of a peritoneal ascites and three s.c. tumors in two animal species was analyzed and correlated with the capacity of the same tumor-bearing host to respond to inflammatory stimuli at sites distant to the tumor. Two of the three s.c. tumors induced systemic defects in macrophage accumulation; the tumor that did not (P-815 mastocytoma) did depress inflammation when transplanted to the peritoneal site. Macrophage accumulation within different tumors varied but, for a given tumor, it occurred in proportion to tumor growth when systemic inflammatory reactions were normal. However, the tumor to macrophage ratio increased dramatically and concurrently with onset of the generalized defect in macrophage inflammatory responsiveness. Accordingly, we concluded that macrophage mobility tested at remote sites is indicative of inflammatory events within the tumor. However, the antiinflammatory effect directed against macrophages is probably not a significant factor in tumor emergence since the required number of tumor cells was large and variable between not only tumors but also sites of transplantation.

The cellular control of growth in cultures of Tetrahymena 2 In fluence of Fe medium and aeration on culture growth and cellular exchange of Ca.

Cultures of Tetrahymena pyriformis were grown exponentially with and without the addition of Fe and with no aeration. During the prestationary growth phase of all the cultures, there was a decrease in the cellular Fe concentration in the water insoluble cell fraction (IS) containing membranes and mitochondria, simultaneous with an increase in the Ca concentration in the water soluble cell fraction (S) containing ribosomes. This has been correlated to an energy deficit in the cells at the transition to the prestationary growth phase. In spite of the ability of Fe-deficient cultures to concentrate Fe, cultures grown in media with low Fe levels soon showed the lowest cellular Fe content. The high Fe levels seen in cultures grown with no aeration may reflect cellular adaptation to a different gaseous tension in the medium. Determinations with 45Ca showed an initial, large and rapid increase in cell radioactivity which was not correlated to cellular metabolism. After this there was differentiated increase due to the metabolic status of the cells. The following sequence was seen in all the cultures: (1) an increase in the exchange of S-and (mostly) IS-Ca at the end of the exponential growth phase, (2) an accumulation of Ca in the S fraction without an increased exchange (the IS-Ca is less exchangeable), and (3) a renewed increase in the exchange of Ca when the concentration is further increased at the end of the prestationary growth phase.

Cytological changes of the pituitary basophils in rats slowly infused with LRH and with LRH and THR in combination.

Young male rats were iv infused with synthetic LRH (L) and with L and TRH (T) in combination for 1, 3, 24, 48 and 72 hrs at each dose of 1 microgram/hr. All the basophils of the controls infused with saline are divided into the continuous cyclic types, i.e., II-, II/III, III-, III/IV- and III/IV/II-types. The II-, III- and III/IV-type cells correspond, in fine structure, with those of the classical thyrotrophs, LH- and FSH-gonadotrophs, respectively. A 1-hr infusion of L does not induce any serious changes in all the basophils. After a 3-hr infusion of L, the II-type cells disperse from the gland, while the III/IV-type cells diminished the number of their small secretory granules, and the lumina of endoplasmic reticulum are closed. After a 24-hr infusion, the irregularly shaped III/IV/II-type cells which may revert from the III/IV- to the II-type cells are accumulated, whose secretory granules are remarkably reduced in diameter (50--100 nm). There is evidence to show the diffusion mechanism of the secretory granules into the ground matrix. After a 48-hr infusion of L, most basophils take an appearance of III/IV/II-type cells; after a 72-hr infusion, all the basophils show the homologous fine structure. Thus, the morphological changes of the basophils following the L infusion resemble intrinsically those following the T infusion (Soji, 1976b). From these results, it is tentatively concluded that L does not act only on the III-type cells analogous to the "LH-cells", but universally upon a series of basophils. The transformations of the III/IV-type cells into the III/IV/II-type ones and those of the II-type ones into the III- or III/IV-type ones due to a slow infusion of L are inhibited to some extent by the infusion of T + L. The granular releases from the III/IV- and II-type cells due to a slow infusion of L are also inhibited to some extent by the infusion of T + L. For this reason, both T and L may act, not synergistically but antogonistically, upon the transformation of a series of basophils and their granular release.

Turnover of radiolabelled plasminogen and prothrombin in cirrhosis of the liver.

The turnover of purified radiolabelled plasminogen was studied in four patients with cirrhosis of the liver, and that of radiolabelled prothrombin in six patients with cirrhosis of the liver. The cirrhotic patients showed an increased fractional catabolic rate and a decreased synthetic rate, resulting in subnormal plasma levels of plasminogen and prothrombin. The plasma concentration of the two proteins correlated with the synthetic rate, but not with the fractional catabolic rate. Heparin infusion prolonged the shortened half-life of plasminogen in two cirrhotics from 1.25 to 2.10 days and from 1.45 to 1.90 days, and the half-life of prothrombin in three cirrhotics from 2.25 to 2.70 days, from 2.35 to 2.80 days and from 2.40 to 3.70 days. These results indicate that the abnormal turnover of labelled plasminogen and prothrombin in cirrhosis of the liver is due to two mechanisms; increased breakdown, reversible by heparin administration, and impaired synthesis. The decreased plasma levels are, however, mainly caused by decreased synthesis.

A horseradish peroxidase-autoradiographic study of parietopulvinar connections in Saimiri sciureus.

Descending connections from parietal cortex to pulvinar in squirrel monkey were investigated with the autoradiographic method. Somatosensory areas I (SI) and II (SII) were found to project to the oral (PuO) and medial (PuM) subdivisions of the pulvinar. Projections from the posterior parietal region were recorded in circumscribed areas of PuM and the lateral (PuL) and inferior (PuI) subdivisions of pulvinar. Retrograde labeling with horseradish peroxidase (HRP) demonstrated that rostral parietal cortex including the lateral cortex of SI and the rostral part of area 5 received reciprocal projections from PuO and rostral PuM. Injections of HRP into medial and lateral regions of SI also resulted in labeled cells in PuO and PuM. Within the limitations of the HRP technique, the latter results suggest a direct pathway from pulvinar to primary sensory cortex. The experimental results confirm the accepted view of projections from parieto-temporo-occipital "association" cortex to PuM, PuL and PuI. In addition, reciprocal connections of rostral parietal cortex with PuO and PuM were demonstrated.

Role for activated macrophages in resistance against Trichinella spiralis.

To determine whether activated macrophages are important in resistance against the intestinal phase of nematode parasites, we studied Trichinella spiralis infections in mice with normal macrophages and in mice with macrophages activated by either chronic Toxoplasma gondii or acute Listeria monocytogenes infections. The peak T. spiralis adult worm burden in the intestines of normal C57BL/6 or Swiss Webster mice occurred from 6 to 14 days after infection. Subsequent expulsion of worms from the intestines occurred from 8 to 20 days after infection. C57BL/6 mice chronically infected with T. gondii and then challenged with T. spiralis larvae had significantly lower peak intestinal worm burdens (P < 0.05) than normal C57BL/6 mice similarly challenged. Swiss Webster mice infected 7 or 13 days earlier with L. monocytogenes and then challenged with T. spiralis larvae had significantly lower peak worm burdens (P < 0.01) than uninfected mice. The time of expulsion of adult worms was not affected by either infection. Swiss Webster mice infected 42 days earlier with L. monocytogenes (i.e., possessing lymphocytes sensitized to L. monocytogenes but not possessing activated macrophages) did not have a lower worm burden than uninfected mice. Serum factors (e.g., antibody) did not appear to play a role because normal mice injected with serum from L. monocytogenes-infected mice had worm burdens similar to those of mice injected with normal serum. The histopathology of intestines of mice infected with T. gondii or L. monocytogenes was the same as that of normal mice. When T. spiralis larvae were incubated with normal macrophages or macrophages from T. spiralis-infected mice in vitro for 24 h, the number of larvae with adherent T. spiralis macrophages was significantly (P < 0.005) greater than the number of larvae with adherent normal macrophages. These studies suggest a role for activated macrophages in resistance to T. spiralis.

Myoxomas of the jaws.

A retrospective study on 15 patients with myxomas of the jaws was carried out. Follow-up information was obtained in 10 patients. Clinical, radiologic, and microscopic features were examined and the results of extensive resection versus conservative surgery were evaluated. The results seem to be in favor of the latter. Four cases are presented in detail.

Lipid and protein composition of membranes of Bacillus megaterium variants in the temperature range 5 to 70 degrees C.

Membranes were prepared from four temperature range variants of Bacillus megaterium: one obligate thermophile, one facultative thermophile, one mesophile, and one facultative psychrophile, covering the temperature interval between 5 and 70 degrees C. The following changes in membrane composition were apparent with increasing growth temperatures: (i) the relative amount of iso fatty acids increased and that of anteiso acids decreased, the ratio of iso acids to anteiso acids being 0.34 at 5 degrees C and 3.95 at 70 degrees C, and the pair iso/anteiso acids thus seemed to parallel the pair saturated/unsaturated acids in their ability to regulate membrane fluidity; (ii) the relative/unsaturated acids in their ability to regulate membrane fluidity; (ii) the relative amount of long-chain acids (C16 to C18) increased fivefold over that of short-chain acids (C14 and C15) between 5 and 70 degrees C; (iii) the relative amount of phosphatidylethanolamine increased, and this phospholipid accordingly dominated in the thermophilic strains, whereas diphosphatidylglycerol was predominant in the two other strains; and (iv) the ratio of micromoles of phospholipid to milligrams of membrane protein increased three-fold between 5 and 70 degrees C. Moreover, a quantitative variation in membrane proteins was evident between the different strains. Briefly, membrane phospholipids with higher melting points and packing densities appeared to be synthesized at elevated growth temperatures.

Aspartate transcarbamylase synthesis ceases prior to inactivation of the enzyme in Bacillus subtilis.

Aspartate transcarbamylase is synthesized during exponential growth of Bacillus subtilis and is inactivated when the cells enter the stationary phase. This work is a study of the regulation of aspartate transcarbamylase synthesis during growth and the stationary phase. Using specific immunoprecipitation of aspartate transcarbamylase from extracts of cells pulse-labeled with tritiated leucine, we showed that the synthesis of the enzyme decreased very rapidly at the end of exponential growth and was barely detectable during inactivation of the enzyme. Synthesis of most cell proteins continued during this time. When the cells ceased growing because of pyrimidine starvation of a uracil auxotroph, however, synthesis and inactivation occurred simultaneously. Measurement of pools of pyrimidine nucleotides and guanosine tetra- and pentaphosphate demonstrated that failure to synthesize aspartate transcarbamylase in the stationary phase was not explained by simple repression by these compounds. The cessation of aspartate transcarbamylase synthesis may reflect the shutting off of a "vegetative gene" as part of the program of differential gene expression during sporulation. However, aspartate transcarbamylase synthesis decreased normally at the end of exponential growth at the nonpermissive temperature in a mutant strain that is temperature-sensitive in sporulation and RNA polymerase function. Cessation of aspartate transcarbamylase synthesis appeared to be normal in three other temperature-sensitive RNA polymerase mutants and in several classes of spo0 mutants.