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Thefts without motive of pain have been known since the early 19th century. But the problem has not been solved. While they were formerly considered a mental disease, today they are not seen as something special. But they still happen. Only a small percentage of common shop-lifting can be called a psycholopathologic syndrome. Many explanations and analyses have been published which are discussed in detail. In a group described here comprehensively difficult marital situations full of conflict, marital sexual frustration, depression, physical and mental exhaustion and aggressive and suicidal tendencies are found. Theft appears to be closely connected with these. But the pattern of motivation and causation is by no means stereo-typed. In order to clear up such actions one will have to consider as exactly as possible the biographic connection and what happens during the act - quite apart from somatic conditions. Present assessment in reports is totally unsatisfactory. To clear up the controversial questions is urgently necessary.

Spectral measurements of phytochrome are performed after unfolding of the peptide chain. By comparison with bile pigments of known structure, structure 1a, containing a hydrogenated ring A, is deduced for the PR chromophore. Its spectral properties indicate that the chromophore of the physiologically active PFR form has lost the double bond of the bridge joining rings A and B.

A micro-method is presented which enables the fast and exact determination of acid-hydrolyzed acylneuraminic acids in erythrocyte membranes. Erythrocytes from 1 ml of human and rabbit blood containing ACD buffer are, washed and hemolyzed on Millipore filters of pore size 1.2 mu. Acylneuraminic acids are released from the erythrocyte membranes still on the filters under the optimal conditions of 0.1 N HCl at 80 degrees C for 50 min. A prerequisite for the determination of the true amount of acylneuraminic acids using the periodic acid/thiobarbituric acid assay is the small-scale extraction of lipids from the hydrolysate and anion-exchange chromatography of acylneuraminic acids. The values thus obtained must be corrected, as 20% of acylneuraminic acids are destroyed during acid hydrolysis. In samples of human blood from 10 healthy individuals, on an average 223 nmol acylneuraminic acids per ml of packed erythrocytes were found, and in the same amount of rabbit erythrocytes, 1e method for a screening of the acylneuraminic acid content of erythrocyte membranes in hemolytic diseases or of other cell membranes is discussed.

Human liver contains three chromatographically distinct forms of non-specific acid phosphatase (EC 3.1.3.2). Acid phosphatases I, II and III have molecular weights of greater than 200 000, of 107 000, and of 13 400, respectively. Following partial purification, isoenzyme II was obtained as a single activity band, as assessed by activity staining with p-nitrophenyl phosphate and alpha-naphthyl phosphate on polyacrylamide gels run at several pH values. With 50mM p-nitrophenyl phosphate as a substrate, enzymes II and III exhibit plateaus of activity over the pH range 3 - 5 and 3.5 - 6, respectively. Acid phosphatase II is not significantly inhibited by 0.5% formaldehyde. The activity of human liver acid phosphatase II and of human prostatic acid phosphatase towards several substrates is compared. The liver enzyme, is marked contrast to the prostatic enzyme, does not hydrolyze O-phosphoryl choline.

Calf skin collagen was solubilized by incubating acid-extracted calf skin with pepsin at pH 2.0 and 25 degrees C, conditions that did not cause degradation of the triple helical region of collagen. Type III collagen was separated from type I collagen by differential salt precipitation at pH 7.5. The isolated type III collagen contained mainly gamma and higher molecular weight components cross-linked by reducible and/or non-reducible bonds. The isolated alpha1 (III) chains had an amino acid composition characteristic of type III collagen. Denatured but unreduced type III collagen, chromatographed on carboxymethyl-cellulose, eluted in the alpha 2 region, while after reduction and alkylation the alpha1 (III) chains eluted between the positions of alpha1 (I) and alpha2. The mid-point melting temperature temperature (tm) of type III collagen (35.1 degrees C) in a citrate buffer at pH 3.7 was somewhat lower than that of type I collagen (35.9 degrees C). Renaturation experiments at 25 degrees C showed that denatured type III collagen molecules with intact intramolecular disulfide bridges (gamma components) reform the triple helical structure of collagen much faster than reduced and carboxymethylated alpha1 (III) chains.

The author believes that many of the chronic patients in psychiatric institutions and mental health facilities could be helped if physicians were more willing to try different combinations and higher dosages of psychotropic drugs than are commonly used. He presents case studies of two chronic patients who were helped by innovative use of drugs and discusses factors to be considered in implementing high-dosage and versatile drug therapy.

A new variant of glucose-6-phosphate isomerase deficiency is described. The enzyme kinetics and properties were studied. Genetic and electrophoretic data pointed to a double heterozygous state in the patient. These data are compared to the other variants described in the literature until now.

Nowadays, above all dextran, gelatin and starch solutions are available for the infusion theraphy of the various forms of shock. The application of these volume substitutes must be strictly controlled to avoid in particular cardial and pulmonal commplications. Blood transfusion combined with a volume substitute should only be applied in cases of heavy loss of blood. The treatment of metabolic acidose which usually occurs simultaneously is carried out with an alkaline solution.

The etiologic and pathophysiologic findings described in the first part of this paper have important consequences: The recognition of the specific etiology of diarrhea requires new laboratory methods: most of these, however, are technically easy to perform and do not require a large laboratory. A long-ranging consequence of this changed concept is a well-founded modification of therapy. The most important discovery was, that in a well balanced glucose electrolyte solution sodium and glucose enhance their absorption mutually and increase the absorption of water by solvent drag. Since in most acute diarrheas the mechanisms of absorption of glucose and electrolytes are retained this mechanism can be utilized for fast oral rehydration and reinstitution of normal intestinal homeostasis. Prompt institution of a diet consisting of the previously mentioned glucose-electrolyte solution usually prevents severe dehydration and the need for stationary treatment. The elimination of lactose and long chain fatty acids from the diet prevents continuation of the pathologic osmotic and chemical conditions in the intestine. Antibiotics are not indicated in acute diarrhea with the exception of diarrhea caused by enteroinvasive E. Coli or Shigella, in the case of Salmonella-gastroenteritis even contraindicated. Further research concentrates on the development of drugs for neutralisation of E. Coli enterotoxin and the prevention of diarrheas by development of effective vaccines.

Originally, many of the initiators of the World Population Conference, which took place in Bucharest in 1974, had hoped that the Conference would imply a final breakthrough for the view that family planning measures should be given top priority in all less-developed countries. In fact, however, the Plan of Action passed by the Conference contains very little relating to population and family planning. Instead, the document is dominated by wordy phrases about the necessity of attaining social and economic development in those countries. Will the insight that family planning programs work efficiently only if they are an integral part of programs for the social and economic development of a country lead to such programs being realized? There is every reason to doubt that the plan of Action will have any such effect. The reasons for the underdevelopment of Third World countries cannot be removed through such United Nations resolutions. In the People's Republic of China, family planning is widely accepted, especially in the towns, and now also among the rural population. Limiting the number of children is considered part of China's development effort. China is a less-developed country that is in the process of rapid social and economic development. The issue at stake in other Third World countries is how to achieve a similar development. As soon as this goal is achieved, family planning efforts are meaningful and have a chance of success. The experience of China demonstrates that even there it took time before the efforts succeeded. There are many Third World countries that could, without much difficulty, support a population considerably larger than the present one. But there are no doubt also a number of countries where the population is already so large that a continued population increase would be harmful. The need to achieve rapid development becomes increasingly urgent, not in the least to make it possible to attain a reduced population growth. The sad truth is that so little development takes place in those countries. Without social and economic development, the present rapid population increase will continue in those countries where there is already an overly dense population.

Among the changes that have been brought about in health delivery in the People's Republic of China, the introduction of the barefoot doctor has been one of the most important and effective ways that the government has devised to radically alter the concept of health care. Through close identification with the community in terms of recruitment, training, and practice, the barefoot doctor is a concrete manifestation of the ideological principles of following the mass line and being self-reliant. The paper focuses on the building of rural health services, with special reference to the training of the barefoot doctor as the first-level contact person in primary care in the communes. It describes the training programs in a school of public health and the career mobility possible to the barefoot doctor in joining the ranks of medical practitioners.

In a double-blind study, the influence of Visken on the effect of anticoagulant therapy with Marcoumar was examined. In comparison to a placebo group, neither any influence on the Quick time, nor any increased tendency to haemorrhage bleeding could be detected.

The excretion of the enzyme gamma-glutamyl-transpeptidase and its isoenzymes into the urine was investigated in patients with renal diseases and compared with the excretion of the enzymes leucine-aminopeptidase and lactate-dehydrogenase. In animal experiments an increased excretion of these enzymes was found after autotransplantation. Increased excretion of gamma-glutamyl-transpeptidase was also found in patients with glomerulonephritis and in the polyuric phase of acute tubular necrosis, but not in cases of pyelonephritis and in the oliguric phase of acute tubular necrosis. The alterations of the isoenzyme pattern during diseases with increased enzyme excretion are in accordance with the hypothesis that the enzymes are liberated from the kidney tissue into the urine, and only a minority stems from the blood. Investigation of the excretion of gamma-glutamyl-transpeptidase and its isoenzymes into the urine seems to be of both scientific and clinical interest.

Both alpha- and beta-adrenergic antagonists have been utilized in an atempt to discern the site of action of prostaglandin (PG) and tetrahydrocannabinol (THC) in the eye. Both alpha- and beta-adrenergic antagonists (alpha-antagonists, phentolamine and phenoxybenzamine; beta-antagonists, propranolol and sotalol) cuased a dose-dependent reduction in intraocular pressure and blood pressure and increased total outflow facility. The results are consistent with the concept that both alpha- and beta-adrenergic receptors are present in the anterior uvea and that vasomotor tone is essential to the maintenance of normal intraocular pressure. No antagonist reduced the PG-induced elevation of intraocular pressure unless the blood pressure was severely lowered. All antagonists inhibit the normal PG-induced increase in total outflow facility, indicating that these agents protect the blood-aqueous barrier from breakdown without altering the vasodilatory response to PG. All antagonists reduced the fall in intraocular pressure produced by THC by approximately 50 per cent, except for sotalol which completely abolished the intraocular pressure fall. Only the alpha-adrenergic antagonists prevented the THC-induced increase in total outflow facility. The results indicate that true outflow facility may well be regulated exclusively by alpha-receptors. The data are consistent with the effect of THC being primarily a vasodilation of the efferent blood vessels of the anterior uvea. The partial inhibition by alpha-adrenergic antagonists may also suggest a lesser role of THC on the afferent vessels.

An experimental model is presented demonstrating that penetrating corneal grafts in the rabbit may be rejected by passive transfer into the anterior chamber of specifically sensitized lymphoid cells. Destruction of histo-incompatible corneal endothelium is always marked by the formation of focal pock-like areas of damage in this system, rather than by the typical moving line of rejecting endothelium usually seen in spontaneous graft rejection. Where the transferred lymphoid cells are compatible with the tissues of the graft recipient, the picture is one of a severely affected graft on a field of uninvolved recipient corneal endothelium. Where the lymphoid cells are compatible with the graft and not with the tissues of the recipient, one sees a clear corneal graft surviving on a field of endothelial destruction on the recipient bed. The specificity of these reactions is illustrated in terms of the histocompatibility relationships between corneal donor, graft recipient, and the donor of the sensitized lymphoid cells.

Male Charles River mice, divided into control or experimental groups, received on Day 0 either sterile 0.3 MNaHCO3 in 0.9 per cent saline (pH7.4) intraperitoneal injection or pteroylglutamic acid (200 mug per body weight), similarly buffered to pH7.6, and were sacrificed on Days 0, 1/4, 1/2, 1,2,3,4,7, and 14. The experimental kidneys demonstrated intratubular deposits of pteroylglutamic acid with edema between Days 1 and 4 with cortical scarring by Day 14. The experimental kidneys reached maximal increases in weight (+90 per cent) on Day 2, RNA (+61 per cent, protein (+67 per cent) on Day 3, and DNA (+25 per cent) on Day 4 before falling to below control levels on Day 14. The control kidneys demonstrated the gradual incremental increases of normal renal growth throughout this period. No change in renal size, protein, RNA, or DNA could be detected in those animals who failed to demonstrate renal tubular damage. It is postulated that the response of the kidney to folic acid administration is a reparative response and not a response directed toward accelerated renal growth.

Transport of 3-O-methyl-D-glucose (3-O-MG) by Acholeplasma laidlawii cells was studied. The 3-O-MG transport system appeared to be constitutive in cells grown on 3-O-MG and glucose; the transport process depended on the concentration of substrate used and exhibited typical saturation kinetics, with an apparent Km of 4.6 muM. 3-O-MG was transported as a free carbohydrate and was not metabolized further in the cell. Dependence on pH and temperature and the results of efflux and "counterflow" experiments demonstrated the carrier nature of the transport system. 6-Deoxyglucose and glucose competitively inhibited 3-O-MG transport, whereas maltose inhibited in non-competitively. p-Chloromercuribenzoate, p-chloromercuribenzene sulfonate, N-ethylmaleimide, and iodoacetate inhibited transport of 3-O-MG. Cells were able to accumulate 3-O-MG against a concentration gradient. Some electron transfer inhibitors (rotenone and amytal), arsenate, dicyclohexylcarbodiimide, and proton conductors such as 2,4-dinitrophenol, carbonylcyanide, m-chlorophenylhydrazone, pentachlorophenol, and tetrachlorotrifluoromethylbenzimidazole inhibited this process.

Washed cells of Salmonella enteritidis harvested from a defined medium during logarithmic growth were subjected to starvation in pH 7 phosphate buffer at 37 C. Viability was measured by slide cultures and plate counts. The survival of cell suspensions equivalent to 1 to 10 mg (dry wt)/ml was influenced by cryptic growth. The rate of cryptic growth, assessed by plate counts, increased with cell density and could not be alleviated by starvation with dialysis. Dialysis of the starving culture did retard the onset of cryptic growth but did not eliminate it, indicating that the major substrates for regrowth were relatively large cellular components. In phosphate buffer, 6.7 homologous heat-killed cells allowed for the doubling of one S. enteritidis cell. Cryptic growth was not observed when cells were starved on the surface of membrane filters or in suspensions equivalent to 20 mug (dry wt)/ml (105 cells/ml). Similar half-life survival times were calculated for both these populations, but the shape of their survival curves differed significantly. These differences were attributed to stress factors encountered during cell preparation and during starvation. The half-life survival time of S. enteritidis starved at 20 mug (dry wt)/ml was 140 h in phosphate buffer, 82 h in 3,6-endomethylene-1,2,3,-6-tetrahydrophthalic acid buffer, and 77 h in tris(hydroxymethyl)aminomethane buffer.

A hypothesis that preferential rejection of donor markers by the hex system of pneumococcus is due to lethal double-strand breaks has been examined in terms of its implications for the extent of the excision required. Experiments reported here were directed at asking whether hex-dependent marker efficiency depends on the length of the donor deoxyribonucleic acid (DNA). In the absence of intracellular competition for hex function, there was no detectable effect of DNA size on hex-dependent marker efficiency as donor DNA was sheared from greater than 1 x 107 daltons to 3.6 x 105 daltons. The latter DNA was purified by two successive velocity fractionations to ensure that the activity seen was representative of DNA of that size. Quantitative examination of the system shows that, for the lethal event hypothesis to be true, the excision step has to remove an average of 7,000 to 10,000 nucleotides. This figure is so much greater than that seen in other excision processes that alternate hypotheses should be considered. The presently known properties of the hex system can be accounted for by a model invoking the migratory features of type I restriction enzymes.

A microcalorimetric technique was used for studying the growth of Escherichia coli during anaerobiosis. The growth thermograms obtained are complex and the shape of curves is dependent on the hydrogen lyase activity of the cells. Fermentation balances are given for different culture conditions, and simple growth thermograms are obtained when the hydrogen lyase activity is inhibitied.

The enhancement of ergot alkaloid production by tryptophan and its analogues in both normal and high-phosphate cultures is more directly related to increased dimethylallyltryptophan (DMAT) synthetase activity rather than to a lack of regulation of the tryptophan biosynthetic enzymes. Thiotryptophan [beta-(1-benzo-thien-3-yl)-alanine] is rather ineffective in the end product regulation of tryptophan biosynthesis, whereas tryptophan and 5-methyltryptophan are potent effectors. The presence of increased levels of DMAT synthetase in ergot cultures supplemented with tryptophan or thiotryptophan, and to a lesser extent with 5-methyltryptophan, suggests that the induction effect involves de novo synthesis of the enzyme. Thiotryptophan and tryptophan but not 5-methyltryptophan can overcome the block of alkaloid synthesis by inorganic phosphate. The results with thiotryptophan indicate that the phosphate effect cannot be explained merely on the basis of a block of tryptophan synthesis.

Microcalorimetry has been used to determine the affinity of whole cells of Escherichia coli for glucose, galactose, fructose, and lactose. Anaerobic growth thermograms were analyzed, and the Km and Vmax values for these energy substrates were measured at pH 7.8. Results obtained with this technique using various organisms growing anaerobically on different sugars are compared. This comparison shows that in practically all cases the cellular rate of catabolic activity is a hyperbolic function of the energy substrate concentrations at low sugar concentrations. In some cases this technique also allows determination of kinetics at high sugar concentrations.

A polyol dehydrogenase of broad specificity was purified 178-fold from extracts of the filamentous fungus Cephalosporium chrysogenum. The enzyme was found to act as an oxido-reductase in two substrate-coenzyme systems: D-sorbitol (or xylitol)-nicotinamide-adenine dinucleotide (NAD) and D-mannitol-nicotinamide adenine dinucleotide phosphate (NADP). The dehydrogenase was composed of five isozymes, which, as a mixture, exhibited these properties: Km to D-sorbitol and D-mannitol, 7.15 to 10(-2) M; PH optimum, 9 to 10; molecular weight, 300,000 subunit weight, 29,000; PI, 5.8 to 7.5. The NADP-linked activity was labile to treatment with heat or ethylenediaminetetraacetic acid. Mixed substrate assays support the hypothesis that both NAD-, and NADP-linked activities are associated with isozymes of a single dehydrogenase.

Suspensions of isolated cell envelopes of infectious elementary bodies (EB) of Chlamydia psittaci at alkaline pH showed a rapid, extensive decrease in absorbance, accompanied by the release of a cell envelope component in a sedimentable form. This phenomenon was observed both at 0 C and with envelopes which had been previously heated to 100 C. Monovalent and divalent cations effectively inhibited the turbidity loss, whereas ethylenediaminetetraacetate (EDTA) caused an accelerated decrease in turbidity. The turbidity loss observed after incubation of the envelopes at alkaline pH could be reversed to the level of the initial value by dialysis against distilled water containing Mg2+. Thin-section electron photomicrographs of purified EB exposed to alkaline buffer with EDTA revealed the loss of the internal contents of cells, but these cells still maintained their round shapes. The cell surface of treated EB appeared pitted in negatively stained preparations, whereas intact EB had a smooth surface. Electron microscopic studies on negatively stained preparations of the clear supernatant obtained after the treatment of the envelope with alkaline buffer containing EDTA demonstrated the presence of spherical particles, approximately 6 to 7 nm in diameter, and rodlike particles, which appeared to be made up of two or more spherical particles.

Exposure of isolated cell envelopes from purified infectious elementary (EB) of Chlamydia psittaci to sodium carbonate-bicarbonate buffer at pH 10 plus ethylenediaminetetraacetate (EDTA) results in partial solubilization of the total protein. The released materials represent 20% of the dry weight, 16% of the total protein, 40% of the total carbohydrate, and 9% of the total lipid of the cell envelopes. Sucrose density gradient centrifugation, and Sephadex G-200, Sepharose 4B, or diethylaminoethyl-cellulose column chromatography, reveal a protein-carbohydrate-lipid complex of several hundred thousand molecular weight that contains 50% protein. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the isolated EB cell envelopes reveals two major protein bands, A and B, with estimated molecular masses of approximately 85,000 and 53,000, respectively, both of which also stain for the presence of carbohydrate and lipid. Gel electrophoresis of the protein-carbohydrate-lipid complex reveals two protein bands, C and D, with estimated molecular weights of approximately 17,000 and 13,000, respectively, which contain lipid and a small amount of carbohydrate; bands A and B are not present in the complex. Gel electrophoresis of the cell envelope residues after extraction of the complex with alkali and EDTA shows a single main band, corresponding to the position of band B, which contains protein, carbohydrate, and lipid; band A is completely missing. B and A is believed to be a component of the complex, which is split into two subunits on alkali solubilization.

beta-N-acetylglucosaminidase (EC 3.2.1.30) has been purified from Escherichia coli K-12 to near homogeneity based on polyacrylamide gel electrophoresis in both 0.5% sodium dodecyl sulfate and in 6 M urea at pH 8.5. The purified enzyme shows a pH optimum of 7.7 and the Km for p-nitrophenyl-beta-D-2-acetamido-2-deoxyglucopyranoside is 0.43 mM. The molecular weight of this enzyme, determined by both Sephadex gel filtration and by sodium dodecyl sulfate gel electrophoresis, is equivalent to 36,000. It is shown to be a soluble cytoplasmic enzyme. Studies on the substrate specificites of the purified enzyme indicate that this enzyme is an exo-beta-N-acetylglucosaminidase.

Extracts of dormant microcysts of Polysphondylium pallidum demonstrate pH optima for the hydrolysis of casein at 3.5 and 6.0. During germination the intracellular pH 6.0 caseinolytic specific activity does not change significantly. The pH 6.0 protease is also active on azo-albumin, revealing the same developmental pattern with this substrate. Both acid protease activities are excreted during the germination process. Addition of purified nonspecific protease to cultures speeds up germination, suggesting that the excreted protease may play a role in removal of the microcyst wall. When cycloheximide is added to cultures, complete germination (emergence) is stopped whereas the pH 6.0 protease activity still accumulates to between 50 and 60% of the maximum control activity. Although this suggests that post-translational controls might mediate the accumulation of a portion of the pH 6.0 protease increase, mixing and dilution experiments with cell extracts do not reveal the differential presence of soluble activators or inhibitors of this activity at different developmental stages. The presence of tightly bound enzyme-inhibitor complexes for protease B in dormant microcysts has not been ruled out and is currently under study.

Rifampin-resistant mutants were isolated from Lactobacillus casei S1 and examined for possible simultaneous alteration in nutritional properties. Among the 36 mutants obtained either spontaneously or after mutagenesis with 2-aminopurine, 22 were found to be altered with respect to the specific growth requirements. The majority (20 of 22) of the latter mutants were shown to require L-glutamine in addition to the nutrients required by the parental strain for maximal growth, whereas the remaining mutants had apparently lost the requirement for L-aspartate. Further studies with one of the glutamine-requiring mutants revealed that the rifampin resistance of this strain is due to the resistance of ribonucleic acid polymerase itself and that a single mutation is responsible for both rifampin resistance and the glutamine requirement. These results strongly indicate that a structural alteration of the ribonucleic acid polymerase caused by the rifampin resistance mutation somehow affected glutamine metabolism, possibly through change in selective transcription of the genes involved.

Deoxyribonucleic acid (DNA)-dependent ribonucleic acid (RNA) polymerase (EC 2.7.7.6) from Acinetobacter calcoaceticus was purified to apparent homogeneity and its properties were compared with those of the Escherichia coli B enzyme. The molecular weights of the two native active enzymes as well as their alpha and beta subunits appeared to be similar. No subunit corresponding to that of sigma from E. coli was found, and furthermore no separation between the beta subunits could be detected by gel electrophoresis. A number of different DNAs were transcribed by the enzyme from A. calcoaceticus. Maximal RNA synthesis occurred at pH 8.7, 10 mM Mg2+, or 0.3 mM Mn2+ and at a total ionic strength of 0.1. Higher ionic strengths led to increasing inhibition of transcription and at mu = 0.4 complete inhibition was observed. The mechanism of inhibition of salt was not related to the initiation event as observed with T4 core RNA polymerase (R.Kleppe, 1975). In an attempt to understand the mechanism of inhibition by salt, the effect of ionic strength on the sedimentation properties of the enzyme was investigated. At low ionic strength, enzyme species with sedimentation coefficients, s20,w, of 5.8S, 12.4S, and 19.3S were present. In buffers with higher ionic strengths the relative amounts of the 12.4S species decreased. It is suggested, therefore, that the inhibition of activity at higher salt concentrations is caused by a decrease in concentration of the active enzyme species.

The urea-hydrolyzing activity of a T-strain mycoplasma was studied in experiments using whole cells and cell-free enzyme preparations by measuring the release of 14CO2 from [14C]urea. Under the conditions used, the urea concentration optimum is approximately 5.6 X 10(-3) M urea. The activity is soluble and not membrane bound. It is stable at -70 C for several weeks but is more labile at higher temperatures. The pH optimum is between 5.0 and 6.0. The effect of several inhibitors on the activity was tested and revealed similarities, as well as differences, between T-strain mycoplasma urease activity and the urease activity of other organisms and plants.

An arginine decarboxylase has been isolated from a Pseudomonas species. The enzyme is constitutive and did not appear to be repressed by a variety of carbon sources. After an approximately 40-fold purification, the enzyme appeared more similar in its properties to the Escherichia coli biosynthetic arginine decarboxylase than to the E. coli inducible (biodegradative) enzyme. The Pseudomonas arginine decarboxylase exhibited a pH optimum of 8.1 and an absolute requirement of Mg2+ and pyridoxal phosphate, and was inhibited significantly at lower Mg2+ concentrations by the polyamines putrescine, spermidine, and cadaverine. The Km for L-arginine was about 0.25 mM at pH 8.1 AND 7.2. The enzyme was completely inhibited by p-chloromercuribenzoate. The inhibition was prevented by dithiothreitol, a feature that suggests the involvement of an -SH group. Of a variety of labeled amino acids tested, only L-arginine, but not D-arginine was decarboxylated. D-Arginine was a potent inhibitor of arginine decarboxylase with a Ki of 3.2 muM.

3-Deoxy-arabino-heptulosonic acid 7-phosphate synthase, prephenate dehydratase, tryptophan synthase, and 2,3-dihydroxybenzoylserine synthase enzyme activities are derepressed in wild-type Escherichia coli K-12 cells grown on Fe3+-deficient medium. This derepression is reversed when FeSO4 is added to the growth medium. Addition of shikimic acid to the Fe3+-deficient growth medium caused repression of the first three enzyme activities but not of 2,3-dihydroxybenzoylserine synthase activity. Addition of 2,3-dihydroxybenzoic acid to the Fe3+-deficient growth medium has no effect on any of the above-mentioned enzyme activities. The Fe3+ deficiency-mediated derepression of 3-deoxyarabino-heptulosonic acid 7-phosphate synthase activity is due to an elevation of the tyrosine-sensitive isoenzyme; the phenylalanine-sensitive isoenzyme is not derepressed under these conditions.

When Streptomyces alboniger spores were grown in Hickey-Tresner broth containing 5 muM ethidium bromide, a high frequency of permanently cured aerial mycelia-negative (am-) colonies was recovered. The appearance an am- colonies was time dependent: a very low frequency (0.3%) at zero time, a maximum (9 to 21%) after 2 to 5 days of growth, and a decline again to low frequencies later in the growth cycle. On agar, cured am- colonies of S. alboniger still produced puromycin. The development of aerial mycelia in S. alboniger, S. scabies, and S. coelicolor was also sensitive to glucose repression. Colonies grown on Hickey-Tresner agar containing 2% glucose remained phenotypically am- throughout the observation period. Adenine (2.5 mM or greater), and to a lesser extent adenosine and guanosine, specifically reversed the repression. The accumulation of undissociated organic acids appears to be involved in glucose repression of aerial mycelia formation. However, this does not appear to be the case with puromycin production in S. alboniger; glucose repression was observed over the pH range 5.0 to 7.5.

Highly active, essentially homogeneous, preparations of ferrocytochrome c oxidase (EC 1.9.3.1) have been obtained from both yeast and beef heart by extraction with cholate, fractionation with ammonium sulfate, and replacement of cholate by Tween 20. The molecular weights of the resultant proteins equal 260 +/- 23 X 10(3) and 205 +/- 10(3); they contain seven and six different polypeptide subunits, respectively, all in equimolar amounts, with apparent molecular weights of 42.4, 34.1, 24.7, 14.6, 14.6, 12.3, 10.6 X 10(3), and 47.5, 20.4, 14.5, 14.5, 13.0, 11.0 X 10(3), respectively. By means of apolar chromatography on L-leucine coupled to agarose these enzymes can be stripped of their largest subunit(s) resulting in preparations with molecular weights of 170 +/- 17 X 10(3) and 124 +/- 20 X 10(3), and containing only five polypeptides, with the largest remaining one (molecular weight congruent to 20 X 10(3)) present in less than stoichiometric amounts. This interconversion and subunit removal has been monitored by exclusion chromatography, four systems of acrylamide gel electrophoresis--some with the protein labeled with 125I under denaturing conditions--isoelectric focusing, and hydrodynamic methods. It has virtually no effect on heme a and copper content and on the catalytic parameters of the enzymes. We conclude that subunits I and II in enzymes from fungal, and subunit I in those from animal, sources are dispensable for the catalysis of the oxidation of ferrocytochrome c by, and are probably not essential for the attatchment of prosthetic groups to, these proteins.

Methylglyoxal synthetase, which catalyzes the conversion of dihydroxyacetone phosphate to methylglyoxal and inorganic phosphate, has been isolated and crystalized in good yields from Proteus vulgaris. The enzyme was shown to be homogeneous by a variety of criteria and was found to be a dimer (Mr = 135,000; s20,w = 7.2 S) composed of two apparently identical catalytic and physical properties and their interconvertible nature suggest that they do not represent true isozymes. The enzyme is specific for dihydroxyacetone phosphate and does not form methylglyoxal from glyceraldehyde 3-phophate, glyceraldehyde, or dihydroxyacetone. Nonphosphorylated analogs are neither substrates nor competive inhibitors, but a variety of phosphorylated analogs are competitive with respect to dihydroxyacetone phosphate. The enzyme is inhibited by inorganic orthophosphate in a complex manner which is overcome by dihydroxyacetone phosphate in a signoidal manner

Beef kidney 3-hydroxyanthranilic acid oxygenase has been purified to homogeneity. It is a single subunit protein of Mr = 34,000 +/- 2,000 with a frictional coefficient (f/f0) of about 1.1. The enzyme readily aggregates to form, apparently inactive, higher molecular weight oligomers. The very rapid loss of enzyme activity during the assay was analyzed extensively. It was found to be due to inactivation of the enzyme by the substrate, 3-hydroxyanthranilate, and unrelated to enzyme turnover or oxidation of bound iron. The loss of activity was shown to be a first order decay process, and methods are given for obtaining accurate initial reaction rates under all conditions. Evidence was presented that the enzyme assumes a catalytically inactive conformation at pH 3.4, which only relatively slowly rearranges to an active form at pH 6.5; the rearrangement can be blocked by the presence of substrate. We have found that Fe2+, which is required for enzymatic activity, can equilibrate freely, albeit slowly, with the enzyme during the course of the enzyme reaction even in the presence of saturating 3-hydroxanthranilate. Under assay conditons, the Fe2+ has an apparent dissociation constant of 0.04 mM. The kinetic properties of the enzyme were found to be dramatically different in beta,beta-dimethylglutarate buffer and collidine buffer; both the rate of loss of activity during the assay and the substrate Km and Vmax were affected.

A monolayer reaction system employing tripropionin and siliconized glass beads was used to study the effects of taurodeoxycholate and colipase on the catalytic activity, interfacial stability, and interfacial affinity of porcine pancreatic lipase B (EC 3.1.1.3) The stability and catalytic activity of lipase at the bead-water interface are governed by the same two ionizable groups with pKa values (in the absence of cofactors) of 5.6 and 9.3. Colipase alone or with bile salt caused only a slight perturbation of these values. At low concentrations, 0 to 0.3mM, taurodeoxycholate increases the stability of lipase by 5-fold. At higher concentrations, 0.3 to 0.8 mM, but still below its critical micelle concentration, taurodeoxycholate prevents the adsorption of lipase to the bead-water interface. This appears to be the major mechanism by which this bile salt inhibits lipolysis. Colipase exerts small positive effects on lipase stability and catalytic activity. More importantly, colipase enables the adsorption of lipase in the presence of bile salt, thereby reversing the inhibition.

Three homogeneous preparations of D-alanine carboxypeptidases I have been obtained from Escherichia coli strain H2143, termed enzymes IA, IB, and IC. Enzyme IA purified from the membrane after extraction with Triton X-100 appeared on sodium dodecyl sulfate gel electrophoresis to be a polypeptide doublet whose monomer molecular weights were about 32,000 and 34,000. In addition to D-alanine carboxypeptidase activity, it catalyzed a transpeptidase reaction with several substrates, bound [14C]penicillin G, had a weak penicillinase activity, but was devoid of endopeptidase activity. Enzyme IB obtained from the membrane after LiCl extraction and enzyme IC obtained from the supernatant solution were either identical or extremely similar. They were composed of a single polypeptide whose monomer molecular weight was about 41,000. In addition to carboxypeptidase activity, they catalyzed an endopeptidase reaction, had weak penicillinase activity, and had very poor transpeptidase activity, but did not bind [14C]penicillin G. Some data relating to the mechanism of catalysis by these enzymes are described. Their possible physiological role is discussed.

The binding of p-hydroxymercuribenzoate to human methemoglobin causes a perturbation of the visible heme abosrption spectrum which is expressed by an increase in absorbance in the high spin band regions, 480 to 510 nm and 590 to 640 nm, concomitant with a decrease in absorbance in the alpha- and beta-band absorption regions. The pH dependence of the p-hydroxymercuribenzoate-induced difference spectrum can be accounted for quantitatively by a 5% shift toward higher spin of the aquo form of methemoglobin, a 15% shift toward higher spin of the hydroxide form, and a shift in the apparent pKa for the water to hydroxide transition from 7.92 to 8.04 when mercurial is bound. The rate of these heme abosrbance changes is consistent with the rapid second order formation of the beta93 cysteine, mercury-mercaptide bond and does not represent a change due to the dissociation of methemoglobin tetramers into dimers, even though the latter, slow process does follow mercurial binding. The observation of an increase in spin produced by the binding of a reagent which also promotes dimer formation argues strongly against any direct correlation between an increase in spin and the appearance of deoxyhemoglobin-like conformations.

The observed static difference spectrum produced by inositol hexaphosphate binding to methemoglobin is the sum of a very fast and a slow spectral transition. The more rapid absorbance change is too fast to be measured by stopped flow techniques, whereas the slow change exhibits a half-time in the range 1 to 6 s. From the pH dependence of the rapidly formed difference spectrum and from a series of heme ligand binding studies, the rapid phase is interpreted to reflect a localized tertiary conformational change which immediately accompanies inositol hexaphosphate binding and results in a selective increase in spin and reactivity of the beta chain heme groups. In contrast, the slow phase appears to reflect a first order isomerization process which involves only a small portion (less than 10%) of the hemoglobin molecules and results primarily in a marked alteration of the spectral properties of the alpha chains with little change in spin. While the rapid spectral transition cannot be directly related to the overall quaternary transition which occurs during oxygen binding to ferrous deoxyhemoglobin, the slow spectral transition may represent the abortive formation of a deoxyhemoglobin A-like conformation which is inhibited in both rate and extent by the presence of water molecules bound to the heme iron atoms.

Nerve growth factor (NGF) is a protein composed of two identical chains of mass 13,259. An analysis of the sedimentation equilibrium, sedimentation velocity, and gel filtration behavior of dilute solutions of NGF indicates the existence of a rapidly reversible monomer in equilibrium dimer equilibrium and that the association constant K for the reaction at neutral pH is 9.4 X 10(6)M-1. Reaction mixtures consist of equal concentrations of monomer and dimer at a total protein concentration as high as 1.4 mug/ml, and at 1 ng/ml, monomer accounts for greater than 99% of the total. The latter concentration is 20 to 30 times that required for the biological activity of NGF. Several lines of evidence suggest that the dimerization reaction is highly stereospecific, although its biological significance is not known.

The principal component of normal adult human hemoglobin Ao, was equilibrated under various conditions with 13CO2. In addition, derivatives containing specifically carbamylated NH2-terinal groups in alpha or beta chains, or both, were prepared by treatment with cyanate, and equilibrated likewise to allow the identification of specific resonances observed by 13C nuclear magnetic resonance. In deoxyhemoglobin, a resonanance at 29.2 ppm upfield of external CS2 was assigned to the alpha chain terminal adduct, and one at 29.8 ppm to the beta chain terminal adduct. In the liganded state as the CO derivative, the terminal adduct on both chains showed a common resonance position at 29.8 ppm. Small effects of pH on the resonance positions were observed. Under certain conditions, a resonance was observed at 33.4 ppm, probably not ascribable to a carbamino compound. A carbamino resonance that became prominent at higher pH was found at 28.4 ppm, and is tentatively ascribed to one or more adducts on epsilon amino groups. The beta chain resonances in particular are minimized by the presence of inositol hexaphosphate or 2,3-diphosphoglycerate. Quantitative analysis of the resonance intensities shows that the effects of conversion from the deoxy to the liganded state in reducing the degree of carbamino adduct is much more pronounced for the beta than for the alpha chains.

Cell-free extracts of rat brain catalyze the reactions of the purine nucleotide cycle. Ammonia is formed during the deamination but not the amination phase of the cycle. The activity of adenylate deaminase in brain is sufficient to account for the maximum rates of ammonia production that have been reported. The activity of glutamate dehydrogenase is not sufficient to account for these rates of ammonia production. The activities of adenylosuccinate synthetase and adenylosuccinase are nearly sufficient to account for the steady state rates of ammonia production observed in brain. Demonstration of the cycle in extracts of brain is complicated by the occurrence of side reactions, in particular those catalyzed by phosphomonoesterase, nucleoside phosphorylase, and guanase.

A method has been devised which permits the observation of the loss of active sites promoted by aggregation of alpha-chymotrypsin. When alpha-chymotrypsin in unbuffered solution at pH 7 is mixed with buffered proflavin by stopped flow instrumentation to give a final pH of 3.89, a decrease in active sites occurs, as measured by a decrease in enzyme-dye complex. The decrease in the rate of active sites shows a linear dependence on the square of the concentration of active sites remaining at equilibrium. The kinetic data of the reaction have been correlated with equilibrium measurements. Rate constants for formation and dissociation of dimer are 9.45 X 10(3) M(-1)S(-1) and 1.9 S(-1),, respectively. Calculation of Kdis for dimer from rate constants gives a value of 2.01 X 10(-4) M, while direct determination of Kdis gives a value of 1.44 X 10(-4) M.

The stimulation by calf serum of phosphate uptake into 3T3 cells results from a change in maximum velocity of the transport process with no change in the Michaelis constant. Only arsenate among a series of inorganic structural analogs of phosphate inhibited phosphate uptake indicating a high specificity for the process. The arsenate inhibition was competitive in nature. Papaverine, theophylline, and protaglandin E1, drugs known to maintain high intracellular levels of cAMP, had little effect on serum stimulated phosphate uptake. The phosphate uptake stimulating factor(s) in serum could be distinguised from the 3T3 cell survival and migration factors by stability characteristics, but this factor(s) could not be completely separated from a uridine uptake stimulation activity or growth promoting activity using a variety of serum fractionation procedures. Only partial stimulation of the uptake process was achieved with any one serum fraction indicating a multiplicity of serum components is probably involved in this process. Because of the rapidity of serum activation of phosphate uptake and its apparent independence of intracellular cyclic nucleotide levels, it is suggested that serum factors may stimulate phosphate uptake by inducing structural changes in the phosphate carrier system.

In vitro bioluminescence components of the dinoflagellates Gonyaulax polyedra, G. tamarensis, Dissodinium lunual, and Pyrocystis noctiluca were studied. The luciferases and luciferins of the four species cross-react in all combinations. All of these species possess high-molecular weight luciferases (200,000-400,000 daltons) with similar pH activity profiles. The active single chains of luciferases from the Gonyaulax species have a MW of 130,000 while those from P. noctiluca and D. lunula have a MW of 60,000. Extractable luciferase activity varies with time of day in the two Gonyaulax species, but not in the other two. A luciferin binding protein (LBP) can easily be extracted from the two Gonyaulax species (MW approximately 120,000 daltons), but none could be detected in extracts of either D. lunula or P. noctiluca. Scintillons are extractable from all four species, but they vary in density and the degree to which activity can be increased by added luciferin. Although the biochemistry of bioluminescence in these dinoflagellates is generally similar, the observations that D. lunula and P. noctiluca apparently lack LBP and have luciferases with low MW single chains require further clarification.

The post-cooling toe temperature changes after lumbar sympathetic blockade and after intramuscular administration of an adrenergic alpha-receptor blocking substance (chlorpromazine) were studied in 14 patients with impending gangrene because of peripheral arterial insufficiency. The post-cooling temperature rise was similar after sympathetic blockage and chlorpromazine administration and significantly different from the basal toe temperature changes after cooling. It is concluded that administration of an adrenergic alpha-receptor blocking substance is as good as the lumbar sympathetic blockage for evaluation of a remaining sympathetic vasomotor tone in arterial disease patients.

Stationary-phase, minimal deviation hepatoma H4-II-E-C3 cell cultures that are serum-deprived respond with a biphasic time course of phenylalanine hydroxylase induction when dialyzed fetal calf serum or insulin is added. These two agents induce phenylalanine hydroxylase additively, during both the initial 3-hour and the delayed 24-hour phases. The initial phase of induction by insulin is inhibited by cycloheximide but not by actinomycin D. The delayed induction by both dialyzed fetal calf serum and insulin is inhibited by 10(-6) M cycloheximide and 0.20 mug/ml actinomycin D. H4-II-E-C3 cells in culture do not synthesize the factor(s) in serum that induce phenylalanine hydroxylase.

Ion-pair chromatography offers attractive possibilities in pharmaceutical analysis. The specificity of the separation systems can be varied over a wide range by appropriate selection of the stationary phase. The choice of a suitable counter-ion can also drastically improve the detection limit, permitting the determination of drug substances in low dosage and possibly of by-products or breakdown products. Ion-pair chromatography of tropane and ergot alkaloids has been investigated using picrate as counter-ion. Alumina, Kieselguhr and various grades of silica gel have been tested as supports. Partition properties studied in a batch procedure have been compared with the actual chromatographic conditions. Columns (10 cm) filled with silical gel (particle size, 5 mum; pore size, 1000 A) show the best performance in the separation of hyoscyamine, scopolamine and ergotamine as picrate ion-pairs. Close control of pH and temperature is essential for reproducible separations. Improvements in detection limits between 100 and 300 times have been observed with these systems. Ion-pair extractions of these alkaloids from dosage forms can be used for sample preparation prior to injection on the the column. This provides an added degree of selectivity and sensitivity.

The elution bands of acidic and neutral amino acids of protein hydrolysates, emerging from the column of a cation-exchange resin cross-linked with pure m-divinylbenzene, are narrower than those from a resin prepared from styrene and technical divinylbenzene. As a result of these narrower bands, a more complete resolution of the critical pairs threonine-serine, glycine-alanine and tyrosine-phenylalanine is obtained. The most probable reason for the narrower elution peaks is the more rapid diffusion of the exchanged components through the bulk of the resin as a result of a more regular arrangement of cross-linkages in the cation-exchange resin prepared from m-divinylbenzene.

Oligomers of deoxyadenylic acid, obtained by polycondensation, were covalently attached to polyvinyl alcohol. These polymer-bound oligonucleotides undergo very strong adsorption on DEAE-cellulose such that at neutral pH and with 1 M NaCl, partial desorbtion occurs only above 60 degrees. The use of this PV(pA)n-DEAE-cellulose for the column chromatographic separation of deoxythymidylic acid oligomers obtained by polycondensation, according to the principle of base-pairing, is discussed. Linear oligomers and also pyrophosphate derivatives of thymidylic acid which contain more than five monomer units undergo strong retardation under the conditions of base-pairing. Cyclic oligonucleotides do not show any noticeable interaction with the stationary phase. Thus, through the use of a temperature gradient, it is possible to fractionally separate the polycondensate, giving an average degree of polymerisation of 6--10.

The separation of basic, acidic and neutral drugs from propanol-2 extracts of serum, urine and tissue homogenates at different pH values using a micro-phase extraction technique is described. Following preliminary screening, the various drug-containing fractions obtained are further examined by two-dimensional thin-layer chromatography. The drugs present are identified with reference to documented standards with the aid of a drug colour profile system and RF values relative to three different reference standards. By means of gas chromatographic analysis of the same extracts, semi-quantitative estimates of the amounts of drugs present, which are sufficiently accurate for clinical emergency purposes, can be made in many instances. The main advantages of the system are "clean" extracts with a minimum of background interference, rapidity (4-6 h for a complete analysis) and systematically documented and visually presented behaviour of drugs after spraying with various chromogenic and fluorogenic reagents, allowing the systematic identification of unknown substances.

The chromatographic behaviour of 48 alkaloids has been studied on Bio-Rad AG 1-X4, Cellex D and microcrystalline cellulose, eluting with solutions of different pH but constant ionic strength (0.5). Many interesting separations were effected on both AG 1-X4 and Cellex D layers. The influence of pH on the chromatographic behaviour of alkaloids has been quantitatively studied and an equation was used that expresses the behaviour of the alkaloids on both AG 1-X4 (AcO-) and microcrystalling cellulose layers. The nonapplicability of this equation to Cellex D layers is discussed.

A method for the determination of the urinary excretion level of methylated nucleic acid bases by gas-liquid chromatography (GLC) has been developed. A clean-up procedure prior to GLC analysis consisted of hydrolysis, filtration, charcoal adsorption, and anion exchange. Studies to determine optimum derivatization conditions for conversion of the methylated bases to their trimethylsilyl derivatives and to evaluate GLC parameters and columns to obtain the best separation were conducted. Application of the method was shown by determining the excretion levels of methylated bases in urine of normal controls and of patients with various types of malignancy.

Methylated and major purine and pyrimidine bases were separated and quantified by high-resolution liquid chromatography after hydrolyzing transfer ribonucleic acids (tRNAs). Separation was accomplished by eluting the hydrolyzed samples from an anion-exchange column with a concentration gradient of ammonium acetate at pH 9.2. Isolated sample of tRNA were hydrolyzed to the free bases with a trifluoroacetic acid-formic acid mixture of 200 degrees. Detection limits of 100-200 ng/ml were measured for the methylated bases; analytical data are reported for ten methylated bases plus the four major bases of calf liver and rat liver tRNA.

Under the conditions described for alkaline hydrolysis of reserpine and rescinnamine in absolute and aqueous methanol, and after esterification (with diazomethane) of the resulting acid fraction, methyl 3,4,5-trimethoxybenzoate was quantitatively recovered, whereas methyl trans-3,4,5-trimethoxycinnamate, in normal lighting conditions, was either partly isomerized to methyl cis-trimethoxycinnamate or formed an adduct with a molecule of methanol, yielding methyl 3-methoxy-3-(3,4,5-trimethoxyphenyl)propionate. The structures of the products were established by synthesis, nuclear magnetic resonance studies and mass spectrometry. This investigation of the hydrolytic conditions allowed a reliable and rapid gas chromatographic determination of reserpine and/or rescinnamine in amounts down to 500 and 2000 mug, respectively, to be devised.

A technique for the selective extraction of 3-O-methyldopamine, normetanephrine and metanephrine from a single urine sample has been investigated. After hydrolysis of the conjugates, the diluted mixture is passed through a Dowex 50W-X2 column and the methoxylated amines are eluted by means of concentrated ammonia. The eluate, containing metanephrine, normetanephrine and 3-O-methyldopamine is evaporated, and a solution of the residue in borate buffer is fractionated under strictly controlled conditions on an Amberlite CG-50 column. The three amines so separated are estimated by specific fluorimetric methods. The extraction recovery is 80 +/- 3% for pure solutions and 78 +/- 4% for 3-O-methyldopamine added to urine. The fluorimetric procedure, carried out under well-defined conditions, allows the estimation of 10 ng of 3-O-methethyldopamine. The spectral characteristics of the fluorescent derivative are similar to those obtained with dopamine, so that it can be assumed that iodine oxidation of 3-O-methyldopamine demethylates this compound and oxidises the resulting dopamine to the dopamine fluorophore (5,6-dihydroxy-indole). Of the compounds that might interfere in the fluorimetric procedure, dopamine, DOPA and alpha-methyl-DOPA are destroyed by the ammoniacal elution from the Dowex column and 3-O-methyl-DOPA is eliminated in the effluent from the Amberlite column. The elimination of interfering compounds and the improved separation on Amberlite ensure high specificity for this procedure. We have applied the method to normal urine and to pathological urines from patients with adrenergic tumours or untreated and treated parkinsonian subjects; vital information has been obtained on the prognosis of adrenergic tumours. The presence of large amounts of dopamine, normetanephrine and/or metanephrine does not affect the assay for 3-O-methyldopamine. The method is also applicable to rat and dog urine, and can be applied to tissue extracts with little modification.

Rapid identification of Streptococcus pneumoniae has been reported using counterimmunoelectrophoresis for the detection of specific capsular antigens in serum, cerebrospinal fluid, and urine. Previous clinical studies have failed to detect type VII or XIV pneumococcal antigen. These two types, however, account for a significant portion of pneumococcal disease. The incorporation of a sulfonated derivative of phenylboronic acid in the buffer system provides a method for the sensitive detection of these types in artificial mixtures without greatly reducing the sensitivity for the detection of other pneumococcal types. A problem with false positives encountered using human serum and barbitalbuffer was reduced by the use of buffer containing sulfonated phenylboronic acid.

A method has been developed for the preparation of streptococcal nuclease B by batch adsorpton to diethylaminoethyl-cellulose. The enzyme is homogeneous with respect to nuclease activity and is suitable for use as an antigen in measurement of anti-deoxyribonuclease B levels in sera.

Among 51 strains of anaerobic gram-negative cocci belonging to the family Veillonellaceae, all strains of Veillonella (V. parvula and V. alcalescens) displayed red fluorescence under long-wave (366 nm) ultraviolet light, whereas no Acidaminococcus or Megasphaera demonstrated fluorescence. In contrast to Bacteroides melaninogenicus, growth of Veillonella does not require hemin and menadione, and flourescence is rapidly lost upon exposure to air. The fluorescent component of a strain of V. parvula examined could not be extracted in solution with water, ether, methanol, or chloroform, but was readily extracted with 0.4 N NaOH. Spectrophotofluorometrically, the fluorescence maximum of this extract was 660 nm with an excitation maximum of 300 nm, when measured at pH 7.2 and 25 C. Coupled with the Gram stain, ultraviolet fluorescence may be a useful tool for rapid screening of Veillonella and is particularly helpful for detection and, isolation of this organism from mixed culture.

A variety of bacterins, vaccines, and antisera retained greater than 90% of their original level of mercurial preservative after lyophilization, and this might influence certain uses of these products.

Distribution patterns of added mercury in raw whole milk after equilibration for 30 min and 2 h at 37 C showed a distribution among acid casein, whey proteins, fat globule membrane, and soluble fat globule membrane of 33, 28, 16, and 2%. On the basis of protein content, the fat globule membrane had the highest amount of mercury. Mercury added to milk as mercuric chloride was removed by treatment with thiolated aminoethyl celluloses and reduced human hair. In a 5 min treatment, 70, 43, and 41% of the mercury was removed by thiosuccinylated aminoethyl cellulose, thionitrocarboxyphenylated aminoethyl cellulose, and reduced human hair, respectively, from whole milk initially containing 1 ppm mercury and equilibrated for 2 h at 37 C prior to treatment. After treatment for 60 min, 82, 52, and 64% of the mercury was removed by thiosuccinilated aminoethyl cellulose, thionitrocarboxyphenylated aminoethyl cellulose, and reduced hair, respectively. However, increasing incubation temperature and time prior to treatment decreased the removal efficiencies. Thiosuccinilated aminoethyl cellulose and reduced human hair showed increasing efficiency directly with pH, while thionitrocarboxyphenylated aminoethyl cellulose showed the opposite effect and had higher affinity for mercury at pH 5.5 than at pH 7.5. Moreover, the rate of removal of mercury at 4 C compared to 37 C was much slower. The removal of mercury from soluble casein and soluble whey proteins was more efficient than from micellar casein. Protein, lactose content, and pH of milk were not changed by the polymer treatments.

A nonadrenergic inhibitory nervous system has been demonstrated in the guinea pig trachea. Electrical field stimulation of this system, in the presence of adrenergic and cholinergic blockade, resulted in relaxation of tracheal rings contracted by the mediators of immediate hypersensitivity or histamine. The relaxation was blocked by tetrodotoxin, which indicated that nerve stimulation was responsible for the relaxation. The gastrointestinal tract, which has a similar embryological origin to the respiratory tract, also has a nonadrenergic inhibitory system. In the gastrointestinal tract, this system is thought to be responsible for the relaxation phase of peristalsis, and absence of this system, in the colon and the rectum, is thought to be an explanation for the spastic bowel in Hirschsprung's disease. It is possible that an abnormality of the respiratory nonadrenergic inhibitory system may play a role in the pathogenesis of the hyperreactive airways in asthma. The airways, due to a lack of inhibition, may be either partially contracted or unable to relax, and thus appear hyperreactive to stimuli.

Alkaline phosphatases from different trematodes occupying the same habitat have identical pH otima but different levels of enzyme activities. Isoparorchis hypselobagri, from the fish Wallago attu, shows four to six times more enzyme activity than Fasciolopsis buski, Gastrodiscoides hominis and Echinostoma malayanum, from the pig Sus scrofa, and Fasciola gigantica, Gigantocotyle explanatum, Cotylophoron cotylophorum and Gastrothylax crumenifer, from the buffalo Bubalus bubalis. At least two peaks of activity at different levels of pH were obtained for each trematode examined. Both Gastrodiscoides hominis and Isoparorchis hypselobagri enzymes had three peaks of alkaline phosphatase activity. The optimum temperature for maximum enzyme activity was 40 degrees C, above which rapid inactivation occurred. At temperatures below 40 degrees C, the enzymes of fish and mammalian trematodes did not behave similarly; I. hypselobagri enzyme being active over a wider range of temperature (20 degrees-40 degrees C. Various concentrations of KCN and arsenate proportionately inhibited enzyme activity. NaF Did not significantly influence enzyme activity, while Mg++ and Co++ acted as activators. The extent of inhibition or activation of enzyme activity of different trematodes varied, probably due to species differences. Both inhibition and activation of I. hypselobagri enzyme was higher than in the case of other trematodes.

A simple method was described for the preparation of 125I-labeled type III neumococcal polysaccharide (SSS-III) with a high specific radioactivity which retained the physical and immunologic properties of native SSS-III. SSS-III was used to study the serum and tissue levels of antigen, as well as its excretion, after i.p. injection. When an optimally immunogenic dose (0.5 mug) of antigen was given, greater than 90% of the injected antigen was excreted during the first 3 days after injection; however, after day 3, the SSS-III which remained in each mouse was firmly bound to various tissues, and less than 5 ng SSS-III was released into the circulation daily. SSS-III was also used in a Farr test to measure serum antibody levels; the kinetics for the appearance of PFC/spleen and serum antibody levels were measured at 24-hr intervals after immunization with 0.5 mug of antigen. Maximum PFC/spleen were observed on day 4 after immunization whereas the peak serum antibody level was seen on day 5. The decay of serum antibody level from its maximum value was much slower than that of the PFC/spleen. The data describing the distribution of SSS-III in vivo and the measurement of serum antibody levels indicated that treadmill neutralization was not a factor in determining the serum antibody levels after immunization with an optimally immunogenic dose of SSS-III.

When the number of PFC present in the spleen was measured at 24-hr intervals after immunizing with an optimally immunogenic dose of type III pneumococcal polysaccharide (SSS-III), maximal numbers of PFC were attained 4 days after immunization; thereafter, the number of PFC decreased rapidly. By contrast, serum antibody levels, which were measured in the same mice using a Farr test, reached peak values 5 days after immunization and then declined much more slowly than did the number of PFC. Two factors were found to contribute to this disparity. First, experiments conducted with splenectomized mice showed that extrasplenic antibody synthesis, which began between days 3 and 4 after immunization and peaked on days 6 to 7, accounted for nearly one-third of the total amount of serum antibody produced. Second, the average rate of antibody synthesis by PFC increased through day 6 after immunization and then declined. Antigen-antibody dissociation tests showed that the avidity of the serum antibody obtained 4 to 7 days after immunization was the same. Moreover, during the same interval, all the antibody detected by the Farr test was of the IgM class. Thus, a change in avidity or class of immunoglobulin after day 5 did not account for the disparity observed. The clearance rate of antibody injected i.v. into nonimmune and immunized mice was studied. The data obtained indicated that accelerated clearance of antibody was occurring prior to day 3 after immunization; however, after day 3 the antibody clearance rate was constant and was the same as that found when antibody was injected into nonimmune mice. These findings affirmed the results of previous studies showing that treadmill neutralization was not important in determining the serum antibody levels present after immunization with an optimally immunogenic dose of SSS-III.

Mouse skin contains a NADPH-dependent, aryl hydrocarbon hydroxylase (AHH), which is inducible by polycyclic aromatic hydrocarbons. In general, unsubstituted polycyclic hydrocarbons caused a greater induction of epidermal AHH than substituted one (1,2,3,4-dibenzanthracene greater than 1,2,5,6-dibenzanthracene greater than benz (a)anthracene equal 3-methylcholanthrene greater than 7,12-dimethlbenz (a)anthracene) which did not correlate with their ability to initiate tumors in mouse skin. Two different techniques were used to isolate epidermis and similar results were obtained with both. However, the technique of isolating epidermis using a mild heat treatment required that the temperature be maintained at 52 degrees C for 30 sec. If the temperature was raised to 54 degrees C or above, there was a large reduction in the AHH activity. Isolated epidermis has 4 to 5 times the AHH activity as dermis and about twice that of whole skin. This was true for control mice or mice in which AHH was induced by pretreatment with benz(a)anthracene.

The collagens are the major structural glycoproteins of connective tissues. A unique primary structure and a multiplicity of post-translational modification reactions are required for normal fibrillogenesis. The post-translational modifications include hydroxylation of prolyl and lysyl residues, glycosylation, folding of the molecule into triple-helical conformation, proteolytic conversion of precursor procollagen to collagen, and oxidative deamination of certain lysyl and hydroxylysyl residues. Any defect in the normal mechanisms responsible for the synthesis and secretion of collagen molecules or the deposition of these molecules into extracellular fibers could result in abnormal fibrillogenesis; such defects could result in a connective tissue disease. Recently, defects in the regulation of the types of collagen synthesized and in the enzymes involved in the post-translational modifications have been found in heritable diseases of connective tissue. Thus far, the primary heritable disorders of collagen metabolism in man include lysyl hydroxylase deficiency in Ehlers-Danlos syndrome type VI, p-collagen peptidase deficency in Ehlers-Danlos syndrome type VII, decreased synthesis of type III collagen in Ehlers-Danlos syndrome type IV, lysyl oxidase deficency in S-linked cutis laxa and Ehlers-Danlos syndrome type V, and decreased synthesis of type I collagen in osteogenesis imperfecta.

The extracts of granules of human polymorphonuclear leukocytes hydrolyzed a variety of proteins including human and bovine hemoglobin, human fibrinogen, human and bovine serum albumin, bovine elastin, and casein. The hydrolysis of all the proteins except fibrinogen and elastin was increased by addition of urea. Various inhibitors of trypsin, kallikrein, plasmin, Clr, Cls, and other proteolytic enzymes had no inhibitory effect. Slight inhibition was observed with polyanethol sulfonate and strong inhibition with normal human serum. Serum of patients with hereditary angioneurotic edema having no functional C1-esterase inhibitor was as effective in inhibiting the proteolysis as normal serum. The inhibitor was localized in 4S fractions of normal serum fractionated on Sephadex G-200. Fractionation of normal serum by ammonium sulfate precipitation, Sephadex G-200 filtration, and CM-Sephadex chromatography did not result in appearance of inhibitory activity in more than one protein peak, suggesting the possibility that only one inhibitor might be responsible. Since all fractions which contained the inhibitor of proteolysis also contained alpha1-antitrypsin, since sera of patients having low alpha1-antitrypsin levels contained less inhibitory activity, and since antibodies against alpha1-antitrypsin reversed the inhibition obtained from normal serum, the inhibition of proteolysis may be attributed to alpha1-antitrypsin.

Urinary levels of antibiotics determine the outcome of treatment of most urinary tract infections. The antibacterial effect of gentamicin against Escherichia coli and Pseudomonas aeruginosa in urine was studied. With use of urinary constituents in concentrations normally found in human urine, it was shown that urine has an inhibitory effect that is dependent upon the acidity and total osmolality of the urine, as well as upon the presence of individual solutes. Up to 40 times as much gentamicin may be needed to prevent the growth of E. coli or P. aeruginosa in concentrated, acidic human urine as is required in broth. This inhibitory effect may be particularly important when urinary concentrations of gentamicin are reduced either because of a reduction in dosage or because of decreased excretion due to renal insufficiency.

A large-molecular-weight capsular polysaccharide was isolated from strains of Bacteroides fragilis subspecies fragilis. By means of electron microscopy and staining with ruthenium red, the thick polysaccharide capsule was also visualized. With use of a radioactive antigen-binding assay, antibody to this capsular polysaccharide was demonstrated in antisera prepared in rabbits to each of eight strains of B. fragilis fragilis. Antibody of similar specificity was not found in antisera prepared to Bacteroides melaninogenicus or to strains of Bacteroides fragilis subspecies vulgatus and Bacteroides fragilis subspecies distasonis; such antibody was found in antisera to only one of two strains of Bacteroides fragilis subspecies thetaiotaomicron. The radioactive antigen-binding assay is a sensitive test for the detection of antibody to capsular polysaccharide. This polysaccharide antigen may form the basis of a serogrouping system for B. fragilis.

A simple, reliable assay for serum and red cell folate is described. It uses plain untreated liquid or powdered milk, requiring no special handling or purification, as binder. Such milk makes it possible to ignore endogenous serum folate binder, since crude (but not purified) milk contains a factor which releases folate from serum binder. It simplifies counting radioactivity by employing a gamma emitting isotope of pteroylglutamic acid (PGA), namely the 125I-tyramide of PGA. Like the 3H-PGA assay of Givas and Gutcho, it permits the use of stable PGA rather than unstable methyltetrahydrofolic acid (MeTHFA) standards, because it is carried out at pH 9.3, a pH at which milk folate binder is unable to distinguish PGA from MeTHFA, which is the predominat folate in human tissues. The equipment required to do the radioassay is present in most diagnostic chemistry laboratories. Results are essentially identical to the generally accepted Lactobacillus casel microbiologic method of folate assay, except that false low results are not produced in the radioassay by antibiotics, tranquilizers, and chemotherapeutic agents. Three caveats in its use are the relative instability of 125I-PGA as compared to 3H-PGA, the fact that various powdered milks differ widely in folate-binding capacity, and that only about 60 per cent of commercially obtained skim or powdered milk preparations appear to contain the substance which splits folate from serum binder.

The synthesis and release of sulfated glycosaminoglycans by normal human chondrocytes in culture are markedly affected by environmental pH. The biosynthetic rate is increased threefold as the pH of the growth medium is raised from 7.0 to 8.0. This coincides with a corresponding elevation in total protein and cell growth. The rate of release of newly synthesized sulfated glycosaminoglycans from the cell layer as well as their distribution between intra- and extracellular localization in the cell layer is also modulated by environmental pH. At pH 8, 35 per cent is found within the cells, this value is reduced to 13 per cent at pH 7. Pulse-chase experiments showed that previously incorporated sulfated proteoglycans were released at a faster rate at pH 7 than at pH 8. The data suggest that proton concentrations affect the biosynthesis and the mode of distribution of newly synthesized sulfated glycosaminoglycans.

Experiments were conducted in anesthetized dogs comparing the effects of PGA1, PGE2, and diazoxide on myocardial contractile force (MC). The three agents were given in successive bolus injections intravenously in equidepressor doses and myocardial contractile force was measured by means of a strain-gauge arch sutured onto the right ventricle. The drugs were administered before and during ganglionic (hexamethonium) and beta-blockade (practolol). Both PGA1, and PGE2 caused a marked rise in MC, 24 and 20 per cent, respectively, before blockade and 10 and 11 per cent during blockade. Diazoxide caused only a minimal rise, 0.9 per cent, before blockade and a marked fall, 27 per cent, during blockade. Diazoxide administration during left ventricular bypass indicates that the decrease in MC is not a direct result of alterations in preload or after load. It is suggested that hypertensive patients treated with autonomic blocking agents may be more susceptible to heart failure in response to diazoxide therapy.

This report describes macromolecules that bind (des-aspartic acid1)-angiotensin II, the des aspartic acid1 derivative of angiotensin I, and several biologically active and inactive analogues of these polypeptides. The macromolecules were found in the plasma of approximately 2 per cent of ambulatory adults and hospitalized children and 32 per cent of the patients at two institutions for the mentally retarded. The binding properties of these macromolecules were studied by incubating with peptides labeled with 125iodine, and separating bound from free labeled peptide using small gel filtration columns. The peptide-binding macromolecules from several patients were compared. They showed very similar specificity for a group of arginyl peptides of the des-aspartyl1-angiotensin sequence. The plasma binders differed from one another in their optimum pH and their mobility in electrophoretic fields. Those with more acid pH optima displayed more rapid electrophoretic mobility. The binders fell into two classes based on apparent molecular weight, approximately 140,000 and 250,000. Those with the higher apparent molecular weight contained a large proportion of binder that could be precipitated with antiserum to human IgA. Kinetic measurements showed that the plasma binders were somewhat heterogeneous with respect to affinity for (des-asp1)-angiotensin, with apparent association constants ranging from 10(7) to 10(8) M-1. Binding activity was labile to heat, and to treatment with pepsin or trypsin. It was inhibited by calcium, protamine, streptomycin, and some other cationic compounds. The plasma peptide binder differed in specificity and molecular weight from soluble angiotensin-binding molecules extracted from tissues, and from properties expected of a receptor for angiotensin. These macromolecules may be useful reagents for measuring (des-asp1)-angiotensins. Their presence in plasma samples may interfere with angiotensin assays in some circumstances.

1. The SS 1 fatigues in response to repetitive electrical stimulation. This fatigue is manifested by an increased conduction delay and a decreased SS 1 pulse amplitude. 2. Continued repetitive stimulation leads to the failure of the system. Recovery may take many seconds. Narrow strips of column fail more rapidly than wide strips. 3. The increased conduction delay is explained in terms of a decrease in the population of spiking cells. 4. A computer model is described and analysed. It suggests that conduction between electrically coupled ectoderm cells could be the basis for the SS1. The SS 1 may have properties not so far experimentally demonstrated; for example, under certain conditions it could behave as a local system.

1. The octocorals Alcyonium digitatum, Pennatula phosphorea and Virgularia mirabilis each have a through-conducting nerve net. The nerve net demonstrated electrophysiologically may well be the same as that previously shown by the use of histological techniques. 2. It exhibits both facilitation and defacilitation in the rate of conduction of pulses. 3. The distance of spread of nerve net activity is not limited by the number of stimuli applied. 4. The nerve net controls fast muscle contractions; the frequency of pulses is important in determining which muscles contract and in which sequence. 5. The nerve net is 'spontaneously' active. 6. A previously undescirbed slow system has been identified in Pennatula. It has many of the properties of slow systems in sea anemones and may well be ectodermal. It is suggested that multiple conduction systems are of common occurrence in the Anthozoa.

Injection of an homogenate of identified neuron R15 into the hemocele of Aplysia produced a weight increase of 3-10% within 90 min. Control injections of several other identified neurons or of seawater, were ineffective. The weight increase occurred even when the animals were maintained in 5% hyperosmotic seawater. The activity of the R15 homogenate was retained after acidification to pH 2 and heating to 100 degrees C; but activity was destroyed by proteolytic digestion with Pronase. Dialysis in cellulose dialysis tubing resulted in a significant loss of aion on Sephadex G-50 (nominal exclusion limits 1,500-30,000 daltons), activity was present in the partially included volumes, but was absent in the totally excluded or totally included volumes. The data support the notion that R15 contains one or more hormones involved in ionic regulation or water balance. The results of bioassays of R15 extracts subjected to different treatments are consistent with the hypothesis that activity is due to one or more stable polypeptides of relatively low molecular weight.

The intracellular pH (pHi) of squid giant axons has been measured using glass pH microelectrodes. Resting pHi in artificial seawater (ASW) (pH 7.6-7.8) at 23 degrees C was 7.32 +/- 0.02 (7.28 if corrected for liquid junction potential). Exposure of the axon to 5% CO2 at constant external pH caused a sharp decrease in pHi, while the subsequent removal of the gas caused pHi to overshoot its initial value. If the exposure to CO2 was prolonged, two additional effects were noted: (a) during the exposure, the rapid initial fall in pHi was followed by a slow rise, and (b) after the exposure, the overshoot was greatly exaggerated. Application of external NH4Cl caused pHi to rise sharply; return to normal ASW caused pHi to return to a value below its initial one. If the exposure to NH4Cl was prolonged, two additional effects were noted: (a) during the exposure, the rapid initial rise in pHi was followed by a slow fall, and (b) after the exposure, the undershoot was greatly exaggerated. Exposure to several weak acid metabolic inhibitors caused a fall in pHi whose reversibility depended upon length of exposure. Inverting the electrochemical gradient for H+ with 100 mM K-ASW had no effect on pHi changes resulting from short-term exposure to azide. A mathematical model explains the pHi changes caused by NH4Cl on the basis of passive movements of both NH3 and NH4+. The simultaneous passive movements of CO2 and HCO3-cannot explain the results of the CO2 experiments; these data require the postulation of an active proton extrusion and/or sequestration mechanism.

Transductional analysis was applied to the Pseudomonas aeruginosa mutant PAO14 (hnc-1). This mutant can utilize L-histidinol as sole source of carbon and nitrogen and has a 60-fold increased histidinol dehydrogenase (HDH) content (Dhawale, Creaser & Loper, 1972). Transductional analysis was carried out using 18 histidine-requiring mutants to see where the hnc-1 locus maps in relation to the structural genes of histidine biosynthesis. The hnc-1 marker cotransduced with group IV genes at 97 to 100 % and not at all with group I, which is known to be the structural gene for HDH. The data obtained in the studies of Km (histidinol) and Km (NAD), and the effect of pH and temperature on the HDH activity from PAO1 and PAO14 are in full agreement with the genetic data that the hnc-1 mutation is not in the structural gene for HDH. It is suggested that hnc-1 may be a mutation in a regulatory gene affecting HDH synthesis in PAO14 and may map close to his-IV whose function in histidine biosynthesis is not known.

The vast increase in the population density of the rumen flagellate Neocallimastix frontalis shortly after the host animal has commenced eating is caused by stimulation of a reproductive body on a vegetative phase of the organism to differentiate and liberate the flagellates. The stimulant is a component of the host's diet. The vegetative stage of N. frontalis bears a strong morphological resemblance to that of certain species of aquatic phycomycete fungi, and consists of a reproductive body borne on a single, much branched rhizoid. The flagellates liberated in vivo within 15 to 45 min of feeding lose their motility within I h and develop into the vegetative phase, thus producing a rapid decrease in population density of the flagellates. Conditions for maximum flagellate production are similar to those occurring in the rumpH 6-5, 39 degrees C, absence of O2, presence of CO2. Differentiation of the reproductive body is inhibited by compounds affecting membrane structure and function, but not by inhibitors of protein synthesis. The organism was cultured in vitro in an undefined medium in the absence of bacteria or other flagellates.

Bacteriocins produced by six strains of Rhizobium trifolii were found to be of the relatively low molecular weight, non-phage type. The molecular weights ranged from approximately 1-8 X 105 to 2-0 X 105. All were of protein composition, as indicated by buoyant density (1-32 to 1-34 g/cm3) in CsC1 and by sensitivity to proteolytic enzymes. They were resistant to RNAase but sensitive to DNAase. The six bacteriocins could further be separated into two subgroups on the basis of sensitivity to extremes of pH, binding to filter membranes, activity spectrum on sensitive strains of R. trifolii, and possibly mode of action on sensitive bacteria. Bacteriocin production occurred spontaneously during the early-to mid-exponential phase of bacterial growth in broth culture.

The gamma haemolysin of Staphylococcus aureus 'Smith 5R' was produced on Dolman-Wilson agar overlain with cellophane. Maximal yields of crude lysin with titres of 2000 to 4000 haemolytic units/ml were obtained within 24 h at 37 degrees C in 10% (v/v) CO2 in air, on medium adjusted to pH 7-0. The crude lysin was purified 2700-fold (with 75% recovery) by ultrafiltration, gel filtration and ammonium sulphate fractionation. The specific activity of the lysin was 10(5) haemolytic units/mg protein after the dialysed active precipitate was extracted with NaCl and reprecipitated with ammonium sulphate. Purified gamma lysin was homogeneous by disc electrophoresis and immunoelectrophoresis.

Arginine and methionine transport by Aspergillus nidulans mycelium was investigated. A single uptake system is responsible for the transport of arginine, lysine and ornithine. Transport is energy-dependent and specific for these basic amino acids. The Km value for arginine is 1 X 10(-5) M, and Vmax is 2-8 nmol/mg dry wt/min; Km for lysine is 8 X 10(-6) M; Kt for lysine as inhibitor of arginine uptake is 12 muM, and Ki for ornithine is mM. On minimal medium, methionine is transported with a Km of 0-I mM and Vmax about I nmol/mg dry wt/min; transport is inhibited by azide. Neutral amnio acids such as serine, phenylalanine and leucine are probably transported by the same system, as indicated by their inhibition of methionine uptake and the existence of a mutant specifically impaired in their transport. The recessive mutant nap3, unable to transport neutral amino acids, was isolated as resistant to selenomethionine and p-fluorophenylanine. This mutant has unchanged transport of methionine by general and specific sulphur-regulated permeases.

Aphids transmitted poly-L-ornithine (PLO)-treated tobacco mosaic virus (TMV) when given acquistion and inoculation access periods as brief as 30 s and 2 min, respectively; the ability to transmit was lost within 90 min. Aphids without claws were able to transmit the virus. Transmission thus seems similar to that of nonpersistent viruses. The ratio of virus to polyamino acid, as well as the KCl concentration, markedly affected transmission. Transmission was best from mixtures which contained 250 mug/ml TMV, 2-5 MUG/ML PLO (mol. wt. 120000) and 0-6 M-KCl. A similar mixture favoured transmission when poly-L-lysine (mol. wt. 85000) was substituted for PLO, but with poly-L-lysine (mol. wt. 30 000) it was necessary to decrease the KCl to 0-3 M to obtain transmission. Less KCl (0-08 to 0-24 M) also favoured aphid transmission of PLO-treated potato virus X and tobacco rattle virus. PLO-treated TMV ultracentrifuged in the presence of, and resuspended in, 0-6 M-KCl remained aphid transmissible while PLO-treated virus in 2 M-DCl, which favours greater dissociation of the virus-PLO complex, was transmissible neither before nor after sedimentation by ultracentrifuging, and resuspension in 0-6 M-KCl. these results show that transmissibility is not due to a permanent alteration of the virus by PLO and indicate that the formation of a TMV-PLO complex is required for transmission. Sequential acquisition experiments suggest that PLO may act by binding TMV to receptor sites in aphids. However, the possibility that PLO affects the infection process was not ruled out.

A comprehensive system of community treatment in southwest Denver has reduced the need for adult psychiatric inpatient beds to less than 1/100,000 population. Six small, community-based therapeutic environments, crisis intervention, home treatment, social systems intervention, and rapid tranquilization comprise the essential components of this total community care system. The system operates within a framework of citizen participation and community control, the elimination of formal staff offices, and a focus on working in the real-life setting of the client and his family. To evaluate the effectiveness of community care, patients about to be hospitalized were randomly assigned to a psychiatric hospital or to community alternative treatment. Outcome measures at discharge and at follow-up completed by the client himself, treatment staff, and family members indicate that community treatment was more effective than psychiatric hospitalization.

The authors measured regional cerebral 133xenon (133Xe) blood flow (rCBF), intraventricular pressure (IVP), cerebrospinal fluid (CSF) pH and lactate, systemic arterial blood pressure (SAP), and arterial blood gases during the acute phase in 23 comatose patients with severe head injuries. The IVP was kept below 45 mm Hg. The rCBF was measured repeatedly, and the response to induced hypertension and hyperventilation was tested. Most patients had reduced rCBF. No correlation was found between average CBF and clinical condition, and neither global nor regional ischemia contributed significantly to the reduced brain function. No correlation was found between CBF and IVP or CBF and cerebral perfusion pressure (CPP). The CSF lactate was elevated significantly in patients with brain-stem lesions, but not in patients with "pure" cortical lesiosn. The 133Xe clearance curves from areas of severe cortical lesions had very fast initial components called tissue peaks. The tissue peak areas correlated with areas of early veins in the angiograms, indicating a state of relative hyperemia, referred to as tissue-peak hyperemia. Tissue-peak hyperemia was found in all patients with cortical laceration or severe contusion but not in patients with brain-stem lesions without such cortical lesions. The peaks increased in number during clinical deterioration and disappeared during improvement. They could be provoked by induced hypertension and disappeared during hyperventilation. The changes in the tissue-peak areas appeared to be related to the clinical course of the cortical lesion.

Deans of Nursing who choose to be administrators of the Health Sciences may very well enhance Nursing programs by facilitating the nursing faculty to become leaders through offering service courses in Health, may thereby help to cut the high cost of nursing education, and may make a contribution to other Health majors by sharing their faculty's special expertise in Health theory.

A basal diet or a basal diet plus 1% of cholesterol and 0.33% cholic acid was fed to rats for varying lengths of time and (1) the activities of liver phosphoenolpyruvate-carboxykinase (PEP-CK), tyrosine transaminase (TT), and serine dehydratase (SD); (2) the rate of total hepatic protein synthesis and (3) the concentration of hepatic reduced glutathione (GSH) were quantitated. The specific activity of PEP-CK was significantly depressed by cholesterol plus cholic acid feeding, while the specific activity of TT was unchanged. No significant effect of dietary cholesterol plus cholic acid was found on the total liver activities. In contrast, SD specific activity was increased 3-fold. The rate of (U-14C)-L-leucine incorporation into total TCA precipitable protein following ingestion of cholesterol plus acid was significantly reduced when the data were expressed as dpm (U-14C)-L-leucine/mg protein. After correcting this expression for specific radioactivity of the liver tissue free leucine pool, no significant effect of dietary cholesterol plus cholic acid on hepatic protein synthesis existed. In fact, the amount of 14C-leucine incorporated into protein on a total liver basis was 50% greater for the cholesterol group. On a per gram of liver basis, the concentration of GSH in the liver of rats fed a cholesterol plus cholic acid diet was significantly decreased. Considering the liver enlargement in rats fed cholesterol plus cholic acid, total organ GSH was found to be significantly greater than for rats fed a basal diet.

TTP accelerated ATP-induced superprecipitation of actomyosin in as low a concentration as 30 muM and decreased light scattering by actomyosin. These effects could also be observed in the same way, but to a lesser degree, by addition to TDP. Myosin was able to hydrolyze TTP to TDP, but some important differences were confirmed between myosin TTPase and ATPase. Myosin TTPase was inhibited by actin and showed a much larger Km than that of ATPase. TTP significantly inhibited myosin B ATPase and ATP greatly inhibited myosin B TTPase. These findings suggest that the accelerating effect of TDP and TTP may be due to the binding of thiamine phosphate to the regulatory site of myosin followed by a change in its physical chemical property, rather than due to the competitive binding of thiamine phosphate to the catalytically activity site of myosin.

In our electron-microscopic studies of testicular biopsies, both normal and cryptorchid, we found a simple atrophy of the Leydig cell in the cryptorchid testis. Based on experiments by Raynaud1,2 and Jean3 on pregnant mice, we tried to find the reason for changes in the Leydig cell relating to the etiology of cryptorchidism. We found on electron microscopic study of testes in the offspring of pregnant mice treated with estrogen the same atrophy of the Leydig cell as we see in human cryptorchidism. These changes are not evident when estrogen and HCG are given together. We can conclude from this experiment that lack of gonadotropin stimulation leads to the atrophy of Leydig cells. This atrophy then produces a lack of androgen which could be responsible for cryptorchidism.

In vitro studies have shown that uncoated carbon and carbon coated with an acrylic hydrogel are capable of adsorbing drugs from horse serum at 37 degrees. Increase in the coating weight from 2 to 4% decreased the rate of adsorption but not the total capacity. In vivo data supports the concept of carbon haemoperfusion for use in the treatment of drug overdose.

The interaction of a series of antihistamines with monolayers of L-alpha-dipalmitoyl lecithin has been examined. An increase in the monolayer surface pressure was noted for monolayers spread on the antihistamine solutions, suggesting penetration of the film by drug molecules. At high surface pressures there was an apparent ejection of drug molecules from the film. The ability of the antihistamines to increase surface pressure was correlated with their surface activity at the air-solution interface. The effect of drug concentration on the magnitude of the surface pressure was examined for diphenhydramine hydrochloride. Application of the Gibbs adsorption equation at low surface compressions indicated an approximate area per molecule for diphenhydramine in the film which was in good agreement with the value previously obtained at the air-solution interface. Preliminary measurements showed that the surface pressure increase was larger in the presence of phosphate buffer at pH 6-8. It was not clear whether this effect was caused by the buffer components or was a pH effect.

The binding of chloramphenicol to an albumin-lecithin complex in the presence or absence of premicellar concentrations of both ionic and non-ionic surfactants has been examined. Long chain, strong ionic detergents, such as sodium dodecyl sulphate or cetyltrimethylammonium bromide, severely perturb protein structure and eventually allow full separation of the complex into lecithin and albumin-detergent complexes. The dissociation process is reversible upon the removal of the detergent by exhaustive dialysis. After the splitting of the complex, the amount of antibiotic associated with the lipid-protein mixture increases. Structural alteration of the albumin-lecithin complex and the increase in the binding of chloramphenicol have an effect on the transfer rate of this antibiotic across an artificial barrier consisting of an aqueous dispersion of the same complex, as observed in a model system. It is suggested that a reversible alteration in membrane structure, and consequently in membrane permeability, might be easily effected, at the molecular level, through a reversible dissociation of structural lipoproteins into their components, operated by premicellar concentrations of ionic surfactants. This represents a tentative picture of the possible events taking place within the membrane and modifying the absorption rate of a drug, when it is associated with surfactants in a pharmaceutical preparation.

The effect of blending on rheological properties for an acid and alkaline processed gelatin has been investigated. Blending of weak gels (1-0-3-5% w/v at 25 degrees), resulted in a decrease in gel rigidity whereas in the stronger gels (5-50% w/v at 25 degrees) and solutions (18% and 30% w/v at 35 degrees), an increase occurred. The decrease in structure in the weak gels is considered to be due to coulombic effects, minimum strength occurring for a mixture which possessed zero charge in solution. A tentative explanation for effects in rigid gels and concentrated solutions is offered.

A single dose of (+)-amphetamine (8 mg kg-1, i.p.) administered 4 h before experimentation, reduced the pressor and positive chronotropic effects elicited by this drug (0-6 mg kg-1, i.v.) and augmented the rate of the development of tachyphylaxis to these responses in the pithed guinea-pig preparation. Amphetamine pretreatment reduced the pressor and positive chronotropic effects of phenylephrine (0-1 mg kg-1, i.v.) and the positive chronotropic effects of angiotensin (30 mug kg-1, i.v.). The rate of the development of tachyphylaxis to the cardiovascular responses elicited by phenylephrine and angiotensin was augmented by amphetamine pretreatment. The results suggest that an indirect mechanism (noradrenaline) may in part mediate the cardiovascular effects of these 3 drugs and/or that amphetamine may act as a competitive antagonist at adrenoceptor sites.

The administration of phenylbutazone together with warfarin to dogs resulted in an elevation of the free fraction of warfarin in the plasma from 2-6 to 8-0% thus providing direct support for the notion that phenylbutazone induced inhibition of warfarin binding to plasma proteins. This inhibition as evaluated by a kinetic method was accompanied by a two-fold decrease in the plasma half-life of warfarin from 18-4 h in control animals to 9-6 h in phenylbutazone-treated animals. Marked increases in warfarin-induced hypoprothrombinaemia were observed when at doses up to 8 mg kg-1 (orally) it was given with phenylbutazone (50 mg kg-1, orally). The unbound fraction of warfarin in canine plasma ranged from 1-7 to 4-3% indicating individual differences in the extent of the plasma binding of warfarin in the dog.

The effects of pancuronium bromide infusion on the uptake and release of [14C] noradrenaline (14C-NA) by the isolated, perfused rat heart and on the chronotropic and inotropic activity of the isolated heart were evaluated. Hearts were removed from animals under light ether anaesthesia, transferred to a modified Langendorff perfusing apparatus and perfused with Krebs-Ringer bicarbonate solution at a rate of 5 ml min-1. The effect of pancuronium on the uptake of noradrenaline was determined by perfusing hearts for 5 min with perfusate containing various concentrations of pancuronium and 200 ng ml-1 of 14C-NA. After 5 min pancuronium-treated hearts contained less 14C-NA. The degree of reduced uptake increased with increasing concentrations of pancuronium. In addition, the combination of pancuronium perfusion and electrical stimulation (15 mA for 10 ms at 4 Hz) blocked the 50 min uptake of 14C-NA by the heart to a greater degree than either factor separately. The release of noradrenaline was determined after perfusing hearts with 14C-NA followed by perfusion with solution containing pancuronium but no 14C-NA for 1 h. Pancuronium infusion did not significantly alter the release of 14C-NA from the heart after 1 h of perfusion. The infusion of pancuronium caused a reduction in both the rate and strength of myocardial contraction of the isolated heart which was reversed by perfusion with perfusate free of pancuronium. Following perfusion with pancurnium the rate and strength of contraction of the heart was seen to "rebound" above pre-pancuronium values for a short period. The rebound of myocardial rate and contraction may have been due to the presence of myocardial noradrenaline previously blocked from reuptake by pancuronium since hearts removed from reserpinized animals did not demonstrate "rebound."

The metabolism of (-)-delta1-tetrahydrocannabinol (delta1-THC) has been studied in the isolated perfused dog lung. After intravascular administration of [3H]-delta1-THC there was an overall biotransformation of 12%. Two major metabolites were isolated and identified as 3'-hydroxy-delta1-THC and 4'-hydroxy-delta1-THC. 7-Hydroxy-delta1-THC was also present together with small amounts of 6alpha-hydroxy-delta1-THC and 6beta-hydroxy-delta1-THC. An in vitro experiment using a dog liver microsomal preparation was also carried out and showed that the major metabolites were 6beta-hydroxy-delta1-THC and 6alpha-hydroxy-delta1-THC. 7-Hydroxy-delta1-THC and 1,2-epoxy-hexahydrocannabinol were also isolated together with small amounts of 3'-hydroxy-delta1-THC and 4'-hydroxy-delta1-THC. The side-chain hydroxylated compounds are hitherto undescribed metabolites of delta1-THC.

A sensitive and selective method for the quantitative determination of the quaternary ammonium antiacetylcholine-compound thiazinamium methylsulphate (Multergan) in plasma and urine is described. The procedure is based on ion pair extraction of the compound with iodide as the counter ion. This is followed by gas chromatography using an alkali flame ionization detector. The detection limit is 2 ng ml-1 with a recovery of 88-0 +/- 6-2% from plasma, 91-4 +/- 4-6% from urine. The described method can also be applied to other quaternary ammonium compounds.