Unusual chemical properties of the amino groups of insulin: implications for structure-function relationship. The chemical properties of the three amino groups of insulin were obtained at 10 and 37 degrees C using the competitive labelling technique with acetic anhydride as the labelling reagent. At 10 degrees C, pK values of 7.9, 7.2, and 7.8 were found for the glycyl A1, phenylalanyl B1, and lysyl B29 amino groups. When compared with standard amino compounds by means of a Brønsted plot, the two amino-termini were found to be 'super-reactive' and the lysyl epsilon-amino group buried. In the presence of carbon dioxide at physiological pH values, all three amino groups became much less reactive indicating that they had reacted to form carbamino derivatives. Above pH 8 the reactivities of the glycyl amino terminus and epsilon-amino group increase sharply indicating that insulin is undergoing a conformational change which is most likely a change in its association state. At 37 degrees C the amino groups do not titrate normally but exhibit sharp increases in reactivity over the physiological pH range with the midpoints in the pH reactivity profiles between pH values of 7.0 and 7.3. This behaviour is interpreted as a rapid disaggregation of insulin to form monomers as a result of the ionization of the amino groups. It is concluded that at physiological pH and temperature all three amino groups are deprotonated.


The effect of growth hormone on the metabolism of a tryptophan load in the liver and brain of hypophysectomized rats. Growth hormone antagonizes the induction of tryptophan pyrrolase and tyrosine amino-transferase by cortisol. We have shown that contrary to previous reports, growth hormone is also capable of antagonizing the induction of these enzymes by tryptophan and alpha-methyl tryptophan. As alpha-methyl tryptophan is not metabolized appreciably in the rat, our data show that growth hormone does not act indirectly through changes in the liver tryptophan content as was suggested previously. Growth hormone decreases the rate of tryptophan catabolism in vivo after induction of tryptophan pyrrolase by tryptophan and alpha-methyl tryptophan. Because the rate of catabolism of a tryptophan is slower in animals treated with growth hormone, tissue tryptophan levels and the rate of synthesis of 5-hydroxyltryptamine in the brain are higher in these animals than in those receiving tryptophan alone. Thus, although tryptophan administration raises brain 5-hydroxytryptamine levels, induction of tryptophan pyrrolase in the liver, by the load, limits the extent and duration of the rise in brain 5-hydroxytryptamine synthesis. This has important implications for the clinical use of tryptophan in psychiatric disorders, where tryptophan is given to produce long-lasting elevations of brain 5-hydroxytryptamine.


The reactions of Escherichia coli citrate synthase with the sulfhydryl reagents 5,5'-dithiobis-(2-nitrobenzoic acid) and 4,4'-dithiodipyridine. Citrate synthase of Escherichia coli reacts rapidly with 1 equivalent of Ellman's reagent, 5,5'-dithiobis-(2-nitrobenzoic acid) (DTNB), per subunit, losing completely its sensitivity to the allosteric inhibitor, NADH. When the enzyme is treated instead with 4,4'-dithiodipyridine (4,4'-PDS), all activity is lost. Certain evidence in this paper is consistent with the belief that the sulfhydryl group modified by DTNB, and that whose modification by 4,4'-PDS inactivates the enzyme, are the same. (i) Both reagents abolish NADH fluorescence enhancement by the enzyme. (ii) Saturating levels of NADH and some other adenylic acid derivatives inhibit the reactions with both reagents. (iii) When the enzyme is modified with one equivalent of DTNB or 4,4'-PDS, subsequent reactivity toward the other reagent is greatly decreased. (iv) Following modifications, the DTNB and 4,4'-PDS derivatives spontaneously lose thionitrobenzoate (TNB) or pyridine-4-thione (PT), respectively, in reactions which are thought to involve displacement of TNB or PT by a second enzyme sulfhydryl group, so that an enzyme disulfide is introduced. The introduction of the disulfide bond, if this is what occurs, does not lead to cross-linking of citrate synthase polypeptide chains, as judged by sodium dodecyl sulfate polyacrylamide gel electrophoresis under nonreducing conditions. Certain evidence has also been found, however, that the sites of modification by DTNB and 4,4'-PDS are not the same. (i) DTNB modification desensitizes to NADH but does not inactivate, while 4,4'-PDS inactivates at least 99.9%. (ii) The presumed disulfide from elimination of TNB is also active, while that from PT modification is no more active than the original 4,4'-PDS modified product. (iii) Prior modification of the enzyme with DTNB affords no protection against later inactivation by 4,4'-PDS. The studies therefore indicate a close relationship between the DTNB desensitization and 4,4'-PDS inactivation, but they are unable to identify it exactly. Other properties of the DTNB reaction are also described, and a hypothesis is offered to explain quantitatively the finding that desensitization lags behind modification during the modification of citrate synthase by DTNB.


Distinctive properties of glutamine synthetase from the cyanobacterium Anacystis nidulans. The intracellular levels of glutamine synthetase (GS) in Anacystis nidulans grown under different conditions were determined using a whole-cell assay. Nitrate-grown cells have 64% more GS than cells grown in ammonium sulfate. Nitrogen starvation does not affect GS levels appreciably. Incubation of nitrate-grown cells with ammonium sulfate does not change the ratio of gamma-glutamyl transferase activities stimulated by Mg2+ and Mn2+ ions. An in vitro test of adenylylation indicates that algae do not have an endogenous adenylyl transferase (ATase) and that algal GS is not adenylylatable by the Klebsiella aerogenes ATase. Some characteristics of the GS-membrane complex were determined by centrifugation of the complex under varying conditions of pH and ionic strength. In this way, it was shown that acid pH (4.5) stabilizes the complex and high ionic strength tends to solubilize the enzyme. A simple partial purification of GS (89-fold) was developed based on the sedimentation properties of GS.


A genetic study of cryptorchidism and scrotal hernia in pigs. The genetic parameters of cryptorchidism and scrotal hernia were estimated. The heritability of liability to cryptorchidism identified at birth was about 0.5 and that identified to be normal at birth, but recognized to be abnormal later was almost zero. The heritabilities of scrotal hernia estimated in two herds were 0.65 and 0.86. The genetic correlation between these two defects was 0.20. An equation for calculating selection differentials for family selection was derived and expected changes of incidence resulting from individual, full-sib and half-sib family selection calculated. Practical culling plans were discussed from the aspect of selection response and possible culling rate.


Phosphate uptake in chemostat cultures of Escherichia coli K-12 subjected to periodic beta-glycerophosphate pulsing: a system for assaying alkaline phosphatase. Limiting concentrations of beta-glycerophosphate were pulsed into chemostat cultures of Escherichia coli K-12 at intervals equal to the population doubling time. The resultant culture density fluctuations are interpreted in terms of inorganic phosphate uptake which, in this system, is a function of alkaline phosphatase activity. Information concerning in vivo alkaline phosphatase activity at suboptimal (acidic) pH with very low concentrations of substrate (beta-glycerophosphate) is obtained from kinetic analysis of uptake data.


Utilization of seawater-urea as a culture medium for Spirulina maxima. The possibilities of utilization of seawater enriched with ureas as the culture medium for a blue-green alga, Spirulina maxima, were investigated. Pretreatment by precipitation with NaHCO3 and (or) Na2CO3 was found essential to remove the excess amounts of Ca2+ and Mg2+ present in seawater prior to cultivation. A culture medium as good as the synthetic medium reported in the literature for the growth of S. maxima was obtained after treating seawater with NaHCO3 (19.2 g/L) at pH 9.2 and 35 degrees C for 2 h, filtering to remove precipitates, and enriching with K2HPO4 (0.5 g/L), NaNO3 (3.0 g/L), and FeSO4 (0.01 g/L). The same results were obtained by substituting a small amount (0.2 g/L or less) of either crystalline or polymerized urea for the NaNO3 in the above medium. Growth  of S. maxima was inhibited at higher concentration of urea in the culture medium. The inhibition effect was due to the partial decomposition of urea into ammonia in alkali medium. Tests conducted on the 130-L cultivation open pond also confirmed that the seawater-urea medium supports growth of S. maxima as well as the best known synthetic medium.


Cache Valley virus: isolations from mosquitoes in Saskatchewan, 1972-1974. Eighteen isolations of Cache Valley virus (Bunyaviridae) were obtained from a total of 113,694 mosquitoes collected in Saskatchewan during the summers of 1972 to 1974. Most of the isolations were from mosquitoes collected during August. Culiseta inornata, the most abundant mosquito (38% of total collected), had the highest minimum vector-infection rate (0.83 isolations per 1000 mosquitoes). The virus was also isolated from Culex tarsalis and Aedes vexans. It is indicated in the isolations that the prairie grasslands of the province are enzootic for Cache Valley virus.


Enzymatic hydrolysis of cellulosic materials by Sclerotium rolfsii culture filtrate for sugar production. The hydrolysis of purified celluloses (cotton, Avicel, Cellulose-123, Solka Floc SW40) and cellulosic wastes (rice straw, sugarcane bagasse, wood powders, paper factory effluents) by Sclerotium rolfsii CPC 142 culture filtrate was studied. Factors which effect saccharification such as pH, temperature, enzyme concentration, substrate concentration, produce inhibition, adsorption, and inactivation of enzyme and particle size were studied. Virtually no inhibition (less than 3%) of cellulose hydrolysis by the culture filtrate was observed by cellobiose and glucose up to 100 mg/mL. Filter paper degrading enzyme(s) (but neither carboxymethylcellulase nor beta-glucosidase) was adsorbed on cellulose. The n value in the S. rolfsii system was calculated to be 0.32 for Avicel P.H. 101 and 0.53 for alkali-treated (AT) rice straw indicating penetration of cellulase into AT rice straw. In batch experiments at 10% substrate level, solutions containing 6 to 7%, 3.8 to 4.7%, 4.0 to 5.1%, and 4.2 to 4.9% reducing sugars were produced in 24 to 48 from AT rice straw. AT bagasse, alkali - peracetic acid treated mesta wood and paper factory sedimented sludge effluent, respectively. The main constituent in the hydrolysate from cellulose was glucose with little or no cellobiose, probably due to the high cellobiase content in the culture filtrate.


Bioconversion of wheat straw and wheat straw components into single-cell protein. Several fungi (Aspergillus niger, A. terreus, Cochliobolus specifer, Myrothecium verrucaria, Rhizoctonia solani, Spicaria fusispora, Penicillium sp., and Gliocladium sp.) were isolated from decomposing wheat straw and tested for their ability to utilize whole straw and its components, holocellulose (hemicellulose and cellulose) and cellulose, for the production of single-cell protein (SCP). It was found that C. specifer was the most efficient fungus for protein synthesis with the three substrates. Using potassium nitrate as N source in mixtures of 0.04 g N/g substrate (0.04% wt./vol.) at pH 4.5, it was found that incubation periods of 3, 4, and 5 days were optimal for protein production on cellulose and holocellulose fractions, and whole straw, respectively. Whole native straw was found to be the most recalcitrant to bioconversion into SCP; however, protein production was almost doubled when the lignin component was removed using a mixture of sodium chlorite and acetic acid.


A noninvasive technique for monitoring response to chemotherapy in human acute leukemia. To see whether urine enzyme activities could be used as an index in evaluating the disease status of leukemia patients, we examined the activities of four enzymes: arylsulfatases A(AS-A) and B(AS-B), alkaline phosphatase (AP), and lactate dehydrogenase (LDH). AP and LDH showed no consistent patterns. The activities of AS-A and AS-B correlated well with the patient's clinical status, increasing during progression of disease and decreasing toward normal activities during responses to therapy, as judged from bone marrow cellularity and differential. Among 23 untreated patients with a histologic diagnosis of acute leukemia we found increased activities of the urine enzymes in these proportions: AS-A in 23 patients (100%), AS-B in 22 (95.7%), AP in 7 (30.4%), and LDH in 10 (43.5%). Five patients in remission from acute leukemia had normal activities for all four enzymes. In one patient in remission for more than one year, a rise in urinary arylsulfatase activity preceded observable bone marrow relapse by 4 months. Unlike that of serum of urine lysozyme and serum copper, the determination of urine arylsulfatase activities appears to be a consistent, useful indicator of response to antileukemic therapy. In contrast to the determination of polyamines, the quantitation of arylsulfatase activity is achieved with greater ease and with instrumentation available in most clinical laboratories.


Effect of pH on the ratio of substitution products in DNA after reaction with the carcinogen N-acetoxy-2-acetylaminofluorene. The substitution reaction products of N-acetoxy-2-acetylaminofluorene (N-AcO-AAF) and the N-sulfate (potassium salt) of N-hydroxy-4-acetyl-aminobiphenyl (N-OSO3K-AABP) with DNA from calf thymus were determined after reaction in buffered solutions of 0.10 M NaCl at pH values from 4--9. In the case of N-AcO-AAF, the ratio of N-(guanin-8-yl)-2-acetylaminofluorene (N-(guanine-8-yl)-AAF) to 3-(guanin-N2-yl)-2-acetylaminofluorene (3-(guanin-N2-yl)-AAF) increased 2.2 times over the entire pH range studied, starting at pH 9. With the N-OSO3K-AABP, the total substitution of guanine was much lower (22--34 times) as compared with N-AcO-AAF, and the ratio of N-(guanin-8-yl)-4-acetylaminobiphenyl to 3-(guanin-N2-yl)-4-acetylaminobiphenyl was not affected by a change in pH of the reaction medium. As expected, heat-denatured DNA reacted more extensively with both esters, but an increase in substitution was much more pronounced for the biphenyl derivative (9 times) than for the fluorene compound (2.8 times). Degradation, denaturation or interstrand cross-linking of DNA were not observed under the reaction conditions employed.


Accelerating effect of ascorbic acid on N-nitrosamine formation and nitrosation by oxyhyponitrite. The reaction of nitrite ion with ascorbic acid and its effect on the rate of nitrosation of secondary amines have been investigated by differential pulse polarography in aqueous acidic solution. Ascorbic acid shows nonuniform behavior: it accelerates the nitrosation of N-methylaniline between pH 1.00 and 1.95, allows the nitrosation of diphenylamine and iminodiacetonitrile, but inhibits the nitrosation of secondary amines, such as dimethylamine, diethylamine, proline, hydroxyproline, N-methylaminoacetonitrile, N-methylaminopropionitrile, and sarcosine. The nitrosating agent generated by the reaction between ascorbic acid and nitrite ion appears to be oxyhyponitrite ion (N2O3-2).


Immunosuppressive effects of sulfato-trans-(-)-1,2-diaminocyclohexaneplatinum(II). Sulfato-trans-(-)-1,2-diaminocyclohexane platinum(II) is a new antitumor agent. Its effect on immune responses was investigated. This agent inhibited lymphocyte transformation in response to phytohemagglutinin, pokeweed mitogen, and concanavalin A. It inhibited antibody plaque-forming spleen cells in AKR/J mice at doses ranging from 2.5 to 7.5 mg/kg i.p. It also prolonged the survival of skin grafts against major histocompatibility barriers in C57BL/6J mice transplanted with tail skin from CBA/J mice. The effective dose ranged from 2.5 to 5 mg/kg. This compound inhibited graft-versus-host reaction in three-week-old AKR/J X DBA/2JF1 mice receiving spleen cells from AKR/J mice i.p. Significant inhibition of graft-versus-host reaction was seen with doses ranging from 1 to 7.5 mg/kg i.p. These results suggest that this drug is immunosuppressive.


Maintenance of adult rat hepatocytes on C3H/10T1/2 cells. A procedure is described for maintaining primary cultures of adult rat hepatocytes on a layer of irradiated C3H/10T1/2 cells. These hepatocytes were capable of metabolizing the liver carcinogen N-2-acetylaminofluorene to water-soluble products and after 14 days in culture could still metabolize approximately 70% of the Day 1 level. Hepatocytes maintained on the C3H/10T1/2 cells were inducible for the liver-specific enzyme tyrosine aminotransferase, and exhibited approximately a 4-fold induction by hydrocortisone during a 10-day culture period. Morphologically, these hepatocytes retained many characteristics of hepatocytes in vivo. By contrast, hepatocytes maintained on plastic lost both N-2-acetylaminofluorene-metabolizing ability and tyrosine aminotransferase activity by Day 5. This was presumably due to degeneration of the hepatocytes and an overgrowth by fibroblasts. The maintenance of morphologically and biochemically functional hepatocytes in culture on feeder cells may provide a valuable approach for studying drug metabolism and liver cell transformation in vitro.


Stability and preliminary pharmacokinetic studies of 1-(2-chloroethyl)-3-[1-(5'-paranitrobenzoyl-2',3'-isopropylidene)-alpha, beta-D-ribofuranosyl]-1-nitrosourea (RFCNU), a nonimmunosuppressive nitrosourea. Using high-performance liquid chromatography, the stability of RFCNU was monitored as a function of pH in aqueous buffers at 37 degrees C and as a function of temperature in plasma. The kinetics of degradation of RFCNU are apparently first-order. The log kappa-pH profile demonstrated the hydroxyl ion-catalyzed solvolysis and a maximum stability around pH 3.0. This analytic assay was reliable for quantitating intact RFCNU in biologic fluids. After administration of 400 mg of RFCNU orally to a female patient, no intact drug was excreted in the urine and plasma levels were very low.


Structural studies of the capsular antigen from Streptococcus pneumoniae type 26. The structure of the capsular antigen from Pneumococcus type 26 has been determined by using methylation analysis, periodate-oxidation studies, and n.m.r. spectroscopy of the original and the dephosphorylated product. It is considered that the polysaccharide is composed of repeating-units having the following structure. (formula: see text): The only difference between this structure and that of the type-6 antigen is that the alpha-L-rhamnopyranosyl residue is linked to O-4 of D-ribitol in the former, but to O-3 in the latter.


Enzyme histochemistry of the mesocoxal muscles of Periplaneta americana. Histochemical techniques have been employed to characterize enzymatic activity in the mesocoxal muscles of the cockroach, Periplaneta americana. Through our studies of the enzymes myosin-ATPase, NADH reductase, succinic dehydrogenase (SDH), and lactic dehydrogenase (LDH), we were able to classify fibers within these muscles according to criteria established for muscle fibers of vertebrates. Many of the mesocoxal muscles possess two different and distinct populations of fibers, whereas the remaining muscles are homogeneous with respect to their constituent fibers. The data presented here indicate biochemical heterogeneity for muscles of differing structural and functional features and possible neurotrophic influences upon oxidative enzymes and myosin-ATPase isozymes.


The pigmentary system of planaria. II. Physiology and functional morphology. The pigmentary system of the planaria, Dugesia gonocephala s.l. (Platyhelminthes, Turbellaria, Tricladida), consists of granules contained in chromatophore cells distributed in the parenchyma tissue. The administration of MSH release-inhibiting Factor (M.I.F.) leads to an easily observable general decolouration of the animal due to the migration of the pigment granules towards the deeper-lying cell nucleus. In planarians bisected transversely through the pharyngeal region, the decolouration occurs only in the cephalic segment, and the caudal segment remains dark. When, however, the decapitated caudal segment regenerates a head region, a decolouration response occurs when exposed to M.I.F. The significance of these results is discussed, and an hypothesis on the hormonal regulation of the pigmentary system is proposed.


Presence of negative inotropic agents in canine plasma during positive end-expiratory pressure. Application of positive end-expiratory pressure (PEEP) will reduce cardiac output (CO). Humoral mediation of this event by circulating negative inotropic agents was examined using a rat papillary muscle bioassay. Twenty-seven dogs were anesthetized with an iv pentobarbital infusion. Plasma was obtained before and after 30 minutes of PEEP. The plasma was oxygenated in a small (4.5-ml) papillary muscle chamber using a diffusion membrane. An average PO2 of 416 mm Hg was achieved. PEEP plasma reduced developed tension (Tpd) from 2.16 +/- 1.0 to 1.90 +/- 1.05 g (P less than 0.0001). A fall in Tpd was observed whether or not CO was maintained constant with fluid infusion. Resting tension was unchanged. The percent reduction in Tpd correlated with the fall in CO (r = 0.63, P less than 0.01) when fluid was not infused to maintain CO. Reapplication of control plasma restored Tpd. Barbiturate levels in anesthetized dogs rose from 17.3 to 19.4 microns/ml during PEEP (P less than 0.1). Addition of pentobarbital to normal plasma led to a slight decrease in Tpd only when the concentration exceeded 99 microns/ml. In three experiments on ex vivo perfused hearts, application of PEEP led to lowering of peak systolic pressure (PSP) within 5 minutes. Removal of PEEP restored PSP in a similar time. The results support the hypothesis that the decline in CO with PEEP is mediated in part by a circulating negative inotropic agent.


Participation of adrenergic and noradrenergic neurones in central connections of arterial baroreceptor reflexes in the rat. We examined activities of tyrosine hydroxylase (TH) and phenylethanolamine-N-methyl transferase (PNMT) and concentrations of norepinephrine (NE) in seven brain regions and the spinal cord of Wistar rats with elevated blood pressures 1 week and 4 weeks after denervation of carotid and aortic baroreceptors, and compared them to values in sham-operated control rats. TH activity was increased in the solitary tract nucleus (to 188% of control), parahypoglossal nucleus (to 254%), locus ceruleus (to 191%), and posterior hypothalamus (to 225%) at 1 week but not at 4 weeks after denervation. Similarly, NE concentrations were significantly altered in a number of brain regions at 1 week but not at 4 weeks after denervation. The only change in NE concentration at 4 weeks was in spinal cord where the level was reduced to 80% of control in the denervated rats. In contrast, the only change in PNMT activity 1 week after denervation was in posterior hypothalamus (to 59% of control), whereas at 4 weeks there was in increase in the spinal cord (to 159%) and a decrease in both the anterior and posterior hypothalamus (to 59% and 64% of control, respectively). The experiments suggest that increased activity of noradrenergic neurones in the brain may play a significant role in initiating the increase in pressure produced by baroreceptor denervation, whereas decreased activity of hypothalamic adrenergic neurones may be more important in maintaining the raised pressure. An increase in the activity of both adrenergic and noradrenergic nerves in the spinal cord, however, could contribute to maintaining the increase in blood pressure 4 weeks after denervation.


Cardiac atrial myosin adenosine triphosphatase of animals and humans: distinctive enzymatic properties compared with cardiac ventricular myosin. Cardiac myosin obtained from atria had a higher Ca2+-activated ATPase activity than did cardiac myosin from ventricles in various species of animals and in humans. The increased specific activity of Ca2+-activated adenosine triphosphatase (ATPase) of atrial myosin appeared to correlate with the level of the activity of ventricular myosin ATPase in the animal, since the same order in ATPase activity, as observed in ventricular myosins from various animals, was noted in atrial myosins. The enzymatic properties of atrial myosin also were characterized by no activation by N-ethylmaleimide, low activating energy, and a lower rate of inactivation at alkaline pH compared with the same properties of ventricular myosin. These findings suggest a difference in the myosin molecule at or near the active site, involving some sulfhydryl groups, between the two types of cardiac myosin. The Mg2+-activated ATPase activity, both in the presence and absence of actin (which is thought to be closely related to the basic contraction mechanism), also was enhanced in atrial myosin. Thus, the ATPase activities of atrial and ventricular myosins were different with special reference to the reaction pathway involving calcium and magnesium ions and appear to account for the difference in the velocity of contraction between the atria and the ventricles.


Transient responses of rabbit cerebral blood vessels to norepinephrine: correlation with intrinsic myogenic tone. Transient contractile responses to norepinephrine (NE) of vascular segments from the rabbit vertebral, internal carotid, and basilar arteries rise to a peak within several seconds, and in the presence of the agonist, reverse rapidly, relaxing with a half-time of 15 +/- 3.2 seconds. In the basilar artery, peak contraction is approximately 25% of the maximum response mediated via the "alpha-like" adrenoreceptors and is elicited by NE 10(-7) M. Steady state contractions are seen with higher concentrations. Transient contractile responses are absent in segments from the brachiocephalic and external carotid arteries, and their incidence increases the more rostral along the length of the vertebral and internal carotid artery the origin of the segment studied. They were seen in all preparations of the intracranial vertebral and basilar arteries. There is a good correlation between the occurrence in any particular vascular segment of the transient contractile response and intrinsic tone as assessed by relaxation to papaverine (10(-6) M). The response was blocked by alpha-adrenergic receptor blocking agents and was not elicited by d-NE nor tetrahydrazoline or oxymetazoline. This response may be analogous to the first phase of the biphasic contraction found in many other blood vessels. Since in cerebral vessels the agonist concentration to elicit the first phase is several orders of magnitude lower than the second, it can appear in the absence of the latter.


Preventive effect of ketotifen, a new antiallergic agent, on histamine-induced bronchoconstriction in asthmatics. The preventive effect of ketotifen, a new drug with anti-histaminic and antiallergic properties, on histamine-induced bronchoconstriction was studied by open assessment in twenty-four adult patients with extrinsic asthma. A single oral dose of 1 mg ketotifen reduced the post-histamine mean drop in peak expiratory flow from 33 to 16% of the basal values (P less than 0.001). After a 4 weeks' regimen of 1 mg ketotifen twice daily the post-drug histamine-induced fall in PEF was further significantly reduced (P less than 0.001). Tests performed after 8 and 12 weeks of treatment showed no additional decrease in bronchial reactivity to histamine. Tests performed 1 week after cessation of treatment showed return of bronchial reactivity to the pretreatment level. The results suggest that a single dose of ketotifen has a marked preventive effect on histamine-induced bronchoconstriction and that this effect is enhanced during continued treatment.


Influence of posture on free calcium and related variables. We measured free calcium and related variables before and after the subject changed from the upright to the supine posture, doing 15 separate such experiments on 11 healthy men. After such a change, free calcium (1.7 +/- 0.4%), total calcium (4.6 +/- 0.7%), total protein (11.5 +/- 1.4%), albumin (12.2 +/- 2.0%), total magnesium (3.8 +/- 0.9%), and the activity of hydrogen ion (2.9 +/- 1.0%) decreased significantly (values are means +/- SEM), but promptly reverted when three subjects assumed the alternative posture. Changes in lactate values were not rapidly reversible; sodium and potassium showed no significant change. The mechanism of the changes in free calcium is unclear, but they correlated only with the changes in total calcium and were notably less than the changes in total calcium, indicating that posture will have less effect on the interpretation of free calcium values than on values for total calcium.


An analysis of electrophoretic and microcolumn methods for the separation of hemoglobins A and A2. Parameters of three techniques for quantitating hemoglobin A2 were studied in order to identify problems affecting repeatability and then to compare intertechnique results under selected conditions. Satisfactory repeatability with cellulose acetate electrophoresis and scanning densitometry required an applicator that delivers a constant volume of sample. For cellulose acetate electrophoresis/elution and chromatographic assays a sophisticated absorption spectrophotometer and pH meter are necessary. Even with the most carefully chosen conditions significant intertechnique variation occurs. Although the colums are the most repeatable, trailing (a problem usually associated with hemoglobin electrophoresis) has also been demonstrated with column chromatography. Isoelectric focusing demonstrated the copresence of hemoglobin A and hemoglobin A2 in all trail fractions between the two major peaks and in some fractions of each peak. Standards of low protein concentration could be prepared from column fractions identified by isoelectric focusing as containing only hemoglobin A or hemoglobin A2. Such standards would be useful for assessing the accuracy of hemoglobin A2 quantitation.


Urinary excretion of arylsulfatases in malnourished/vitamin A deficient children. Serum vitamin A (retinol) levels were generally low in all malnourished children (6-15 microgram/100 ml) compared with control children (50 microgram/100 ml). A significant increase in vitamin A after appropriate therapy was observed in all malnourished groups. Dietary supplements of proteins and calories even without extra vitamin A supplements increased serum vitamin A levels in cases of kwashiorkor indicating active mobilization of liver vitamin A. Total urinary arylsulfatase A activity excreted in 24-h or within 8-h in the morning (6 a.m. to 2 p.m.) was significantly reduced in cases of malnutrition with or without mild vitamin A deficiency symptoms. The excretion of arylsulfatase B was not altered. In cases of severe vitamin A deficiency coupled with malnutrition increased excretion of both arylsulfatases A and B was evident. These results on urinary arylsulfatases excretory pattern have been obtained either in samples collected for 24-h or specifically for 8-h (morning) and it is suggested that this test on urinary arylsulfatases may prove useful for detection of acute vitamin A deficiency with malnutrition in field studies. A ratio of arylsulfatases A/B of 2.0 or less seems to indicate mild malnutrition, the normal ratio being 3.4. Furthermore a low ratio coupled with increased excretion of both arylsulfatases A and B may be considered specific for acute vitamin A deficiency.


gamma-Glutamyltransferase in human and mouse breast tumours. A series of experimental mouse tumours were assayed for their gamma-glutamyltransferase activities. Significantly raised activities were found in a transplantable spontaneous mammary carcinoma compared to normal or lactating mouse breast. A study was therefore undertaken of human breast tumours. Carcinomas showed significantly elevated enzyme levels when compared with normal tissue or histologically uninvolved tissue from a breast containing a carcinoma. Fibroadenoma and chronic mastitis also showed significantly elevated levels when compared with normal tissue and did not differ significantly from carcinoma tissue. Benign breast cyst fluid showed very high levels of enzyme activity. Binding properties of the enzyme to Con A-Sepharose suggested that while normal tissue and fibroadenomas contained only asialated enzyme, carcinomas, chronic mastitis and cyst fluid contained a substantial proportion of sialated enzyme.


Heterozygote advantage in cystic fibrosis: mosquito tests. Tests to demonstrate a preference by mosquitoes for stinging controls as opposed to obligate heterozygotes for Cystic Fibrosis proved negative. If a heterozygote advantage caused a lower malarial incidence in carriers in South West Africa, it must have worked through the malarial parasite being adversely affected by a serum factor. This remains to be tested.


Drugs for inhibition of premature labor. Effective inhibition of premature labor depends on prompt initiation of treatment. The author discusses factors initiating parturition, and the benefits and risks for mother and child of administration of alcohol, beta adrenergic agents, magnesium sulfate, and other agents that may counteract them.


Inhibition of rat liver mitochondrial 3-hydroxy-3-methylglutaryl-CoA lyase by succinyl-CoA. 1. Succinyl-CoA inhibits 3-hydroxy-3-methyl-glutaryl-CoA lyase (EC 4.1.3.4) when added to purified preparations of the enzyme. 2. The apparent Ki value is 2.1 x 10(-4) mol/l and the inhibition has the features of a partially competitive inhibition. 3. The effect of succinyl-CoA both added and enzymically produced on the lyase activity of sonically disrupted rat liver mitochondria results in decreased acetoacetate formation. 4. This occurs with mitochondria obtained from normal, starved and streptozotocin-diabetic rats.


Ammoniagenesis by the isolated perfused rat kidney: the critical role of urinary acidification. 1. The effect of metabolic acidosis simulated in vitro on ammoniagenesis was investigated by using the isolated kidney of the rat perfused with an albumin Krebs-Henseleit medium containing glutamine and glucose. 2. Addition of HCl to a perfusate of normal bicarbonate concentration resulted in a prompt increase in urine flow rate, decrease in fractional sodium reabsorption and decrease in urine pH. 3. A minimum urine pH as low as 5.15 was achieved, with an average value of 5.92, indicating that this preparation has the capacity to acidify normally. 4. In contrast with studies in vitro with other preparations, with the functional perfused kidney a diminution in perfusate bicarbonate concentration resulted in a prompt increase in ammonia production, which was strikingly correlated with the decrease in urine pH. 5. The increase in ammonia production was diminished in studies carried out with a non-urinating kidney, in comparison with those that exhibited significant urine acidification. 6. These data suggest that a decrease in urine pH with trapping of ammonia in the urine may be a critical stimulus for increased ammonia production in acute metabolic acidosis.


Effect of acid-base changes on the intracellular sodium, potassium and water content of human leucocytes in vitro. 1. Leucocytes were isolated from blood of healthy volunteer subjects and incubated in media of which the bicarbonate, PCO2 and pH composition were varied. 2. The intracellular sodium, potassium and water content of leucocytes were virtually unaffected by the acid-base composition of the media used.


Catabolic effects of adrenaline and angiotensin II in the perfused liver of normal and genetically obese (ob/ob) mice. 1. Rapid effects of hormones on the metabolism of glycogen and fatty acids were studied in the perfused liver of normal and genetically obese (ob/ob) mice. 2. In livers from normal and obese mice adrenaline and angiotensin II stimulated glycogenolysis. 3. These hormones inhibited the synthesis de novo of long-chain fatty acids in livers from normal mice, but not in livers from obese mice. 4. The proportion of acetyl-CoA carboxylase in the active form was decreased by adrenaline but not by angiotensin II in livers from obese mice. 5. The potency of hormone effects on liver suggests that they could occur in the intact animal. 6. The results add to the evidence that hepatic fatty acid synthesis in genetically obese (ob/ob) mice is irreversibly resistant to inhibition by a range of hormones. Such resistance could be of primary significance in the pathogenesis of the obesity.


Effect of phenobarbitone on plasma apolipoprotein B and plasma high-density-lipoprotein cholesterol in normal subjects. 1. Further observations from an earlier study in which phenobarbitone in a dose of 180 mg daily was administered to ten normal men and women for 3 weeks are reported. There was a significant increase in plasma high-density-lipoprotein (HDL) cholesterol concentration and in the concentration of both total plasma and low-density-lipoprotein (LDL) apolipoprotein B. 2. There was no change in the ratios of the cholesterol:apolipoprotein B and triglyceride:apolipoprotein B in LDL. 3. There was no significant change in plasma very-low-density-lipoprotein (VLDL) apolipoprotein B concentration and the proportion of lipid and apolipoprotein B in VLDL remained unchanged. 4. There was no change in the ratio of HDL:LDL cholesterol concentrations.


L-asparaginyl-tRNA synthetase and L-asparagine synthetase activities of L-asparaginase-sensitive and -resistant forms of the mouse Gardner lymphoma 6C3HED. 1. The mouse Gardner lymphoma 6C3HED was grown in ascites fluid in a form sensitive to the action of L-asparaginase (line 1), in another form which was resistant to L-asparaginase (line 2) and in a third form with partial sensitivity to L-asparaginase (line 3). 2. The L-asparaginyl-tRNA synthetase activities of extracts of the tumour cells, cultured both in the mouse and in vitro, were determined. Two of the lines, 1 and 3, in early passage numbers, showed a derepression mechanism involving L-asparagine. Mutation occurred with these lines resulting in the L-asparaginyl-tRNA synthetase activity of all the tumour cell lines being the same. 3. Cells of line 1 had low L-asparagine synthetase activity, which was unchanged by altering the supply of L-asparagine in vitro. Cells of lines 2 and 3 exhibited L-asparagine synthetase activities, which changed with the supply of L-asparagine. 4. It is not certain that L-asparagine synthetase activity of L-asparaginase-sensitive cells is controlled by L-asparaginyl-tRNA acting as a corepressor.


Effect of intravenous sodium lactate on renal tubular reabsorption of phosphate in man. 1. The effects of sodium DL-lactate and sodium chloride (2.5 mg/kg as 865 mmol/l solutions given by intravenous infusion over 20 min) on the renal tubular reabsorption of phosphate have been compared in five normal adults. 2. Sodium lactate produced a marked but transient increase in urinary phosphate excretion due to a reduction in net renal tubular reabsorption of phosphate; the mean value of the maximum rate of renal tubular reabsorption of phosphate/unit of glomerular filtration rate (TmP/GFR) decreased from 1.14 to 0.82 mmol/l. 3. This effect was not due simply to expansion of the volume of the extracellular fluid, since the reduction in TmP/GFR after sodium chloride infusion was less marked, nor did it seem to be due entirely to alkalinization of the urine since the maximum increase in urinary pH occurred 20--40 min after the maximum decrease in TmP/GFR.


Effects of diphosphonate and colchicine administration upon acid-base changes induced in rats by bilateral nephrectomy. 1. The effects of disodium ethane-1-hydroxy-1,1-diphosphonate (EHDP) and colchicine on acid--base balance were examined in intact and nephrectomized rats. 2. Both drugs increased extracellular hydrogen ion concentrations and depressed extracellular bicarbonate concentrations in nephrectomized rats compared with controls but did not alter these parameters in intact animals. 3. Intracellular hydrogen ion concentrations in the skeletal muscle of nephrectomized rats given EHDP were higher than those of control animals. 4. It is postulated that colchicine and EHDP inhibit skeletal buffering of non-volatile acids produced endogenously in nephrectomized rats.


Absence of adrenergic mediation of agonist response to [Sar1,Ala8]angiotensin II in conscious normotensive and hypertensive dogs. 1. In the conscious normotensive and two-kidney Goldblatt hypertensive dog a transient agonist response to the intravenous infusion of saralasin (1 microgram min-1 kg-1)was manifested by a small increase in blood pressure (6-12) mmHg) and 28-30% increase in renal vascular resistance. 2. These increases in blood pressure and renal vascular resistance were unaffected by administration of either phentolamine or guanethidine. 3. The agonist response in the conscious dog is most likely accounted for by a direct action of saralasin on vascular angiotensin receptors.


Dependence of deoxycorticosterone/salt hypertension in the rat on the activity of adrenergic cardiac nerves. 1. Chronic hypertension was induced in Wistar rats with intact kidneys by subcutaneous implantation of 50 mg of deoxycorticosterone acetate (DOCA) in wax and addition of sodium chloride (9 g/l) to the drinking water. 2. The development of DOCA/salt hypertension, as monitored by tail-cuff plethysmography, was prevented by: (a) destruction of the peripheral adrenergic nerves with neonatal administration of guanethidine (80 mg/kg subcutaneously for the first 14 days postnatally); (b) bilateral stellate ganglionectomy; (c) oral administration of the beta-adrenoreceptor antagonists propranolol or atenolol (1 mg day-1 kg-1) during the period of DOCA/salt treatment. 3. The dose of DOCA used was sufficient to inhibit the atrial Uptake2 pathway completely: this process appears to participate in termination of action of neurally released noradrenaline in the heart. 4. It is suggested that this model of DOCA/salt hypertension is due to adrenergic enhancement of cardiac output in the presence of an increased sodium load. The enhancement may be partly due to deficient myocardial inactivation of noradrenaline.


Effects of beta-adrenoreceptor antagonists on sino-aortic baroreflex sensitivity and blood pressure in hypertensive man. 1. Sensitivity of the sino-aortic baroreflex was investigated before and after acute (23 patients) and chronic (23 patients) beta-adrenoreceptor antagonism in patients with essential hypertension. 2. Sensitivity was inversely related to age (r = -0.60) and systolic blood pressure (r = -0.46); a positive relationship was noted between sensitivity and initial pulse intervals (r = 0.40). 3. Sensitivity increased significantly in patients less than 40 years of age after chronic treatment. No change occurred after acute treatment or in older patients treated chronically. 4. The fall in ambulatory intra-arterial blood pressure after chronic treatment was unrelated to alteration of baroreflex sensitivity.


Biochemical discrimination of Hurler and Scheie syndromes. 1. Homogenates of cultured skin fibroblasts derived from patients with alpha-L-iduronidase-deficiency disorders (Hurler and Scheie syndromes) were capable of hydrolysing iduronosyl anhydro-[1-3H]mannitol 6-sulphate although at considerably reduced rates compared with normal controls. 2. The Vmax. values of alpha-L-iduronidase from patients with Hurler or Scheie syndromes and from normal controls were 11, 12 and 833 pmol min-1 mg-1 of protein respectively; the corresponding apparent Km values were 656, 50 and 53 mumol/l respectively. The alpha-L-iduronidases from normal and Scheie fibroblast homogenates were shown to exhibit pH optima at 3.6 and 4.1 and were competitively inhibited by both chloride and sulphate ions: Hurler alpha-L-iduronidase activity exhibited the pH optimum at 3.8 and was also inhibited by chloride and to a lesser extent by sulphate ions. 3. The thermal stability of Hurler, Scheie and normal alpha-L-iduronidase activities at 55 degrees C gave half-lives of approximately 1.0, 2.5 and 1.0 h respectively. 4. These biochemical findings clearly demonstrate enzyme differences for these two clinically distinct phenotypes and provide biochemical evidence that the Hurler and Scheie syndromes result from different allelic mutations.


Effects of anticoagulants on acid-base and blood gas estimations. The use of excessive amounts of heparin to anticoagulate blood samples for pH and blood gas analysis leads to erroneously low PCO2 results, whereas pH and PO2 are relatively unaffected. Derived base deficit values accordingly will be high. Dilution is seldom less than 6% but may exceed 40%, particularly when sampling fron neonates. Sodium citrate and Heller-Paul oxalate solutions were found to be suitable alternatives to heparin, whereas EDTA was not.


The pathology and biochemistry of paraquat. After the administration of paraquat to rats the lung is the organ most severely damaged. The pathology in the lung can be divided into two distinct phases: (1) a destruction phase lasting a few days with damage to the type I and type II alveolar epithelial cells, oedema and haemorrhage (most of the rats which die after dosing with paraquat do so during this phase); (2) a reparative phase with regeneration of the epithelium and, in areas of severe damage, a characteristic proliferation of fibroblasts. In both phases of the lesion the death of the rats results from anoxia. Paraquat is selectively accumulated by the rat lung in comparison with other tissues and this accounts, at least in part, for the specific toxic effect in this organ. The accumulation into the lung was shown by in vitro studies to depend on energy and is inhibited by various endogenous and exogenous compounds. This uptake process is not that which has been described for 5-hydroxytryptamine and evidence is presented to suggest that the type I and type II alveolar epithelial cells are sites of accumulation. When paraquat is present in lung cells, it undergoes a cyclical reduction and oxidation with the production of superoxide anion. This radical may lead directly or indirectly to the formation of lipid peroxides and hence to cell death. However, paraquat stimulates the pentose-phosphate pathway and both reduces the level of NADPH and inhibits fatty acid synthesis in the lung. These effects occur when there is only minimal ultrastructural damage to the lung cells. It is suggested, therefore, that the primary mechanism of toxicity of paraquat is the extreme oxidation of NADPH which inhibits vital physiological processes and renders the cell more susceptible to attack from lipid hydroperoxides.


The treatment of glaucoma: role of beta-blocking agents. The sudden development of a red painful eye with blurred vision may be an acute attack of angle closure glaucoma which requires emergency attention. Once the attack is controlled with medication, surgical intervention with a peripheral iridectomy is indicated to relieve relative pupillary block. Eyes subject to angle closure glaucoma are anatomically different with 'crowded' anterior segments. In contrast, open angle glaucoma (the more common form) may progress to near blindness without symptoms. Routine screening of intraocular pressure is, therefore, necessary to make the diagnosis before extensive irreparable damage has occurred. Surgery for open angle glaucoma carries risks of cataract and infection, and is unpredictable. Open angle glaucoma patients are usually treated chronically with specific medications. Beta-Adrenoceptor blocking agents appear to provide a significant new addition to the currently available antiglaucoma medications.


[Effect of calciumhydroxide and its modified forms]. As diffusion experiments show, the singular physicochemical properties which give calcium hydroxide a special place in dentistry only apply to water-containing pastes. With organic hardeners, setting preparations based on "calcium hydroxide" do not have this property and cannot replace water-containing pastes of calcium hydroxide. Partial carbonation of Ca (OH)2 by absorption of CO2 from air does not lead to any lowering of pH of the Ca(OH)2 paste. The pH of the calcium hydroxide determined potentiometrically at 20 degrees C was 13.0.


Reaction rates of superoxide radicals with the essential amino acids. Upper limits for the rates of reaction of amino acids with superoxide radicals have been determined spectrophotometrically by the stopped flow method. Rate measurements at 23 degrees C for the reaction of HO2 with amino acids were made in the pH range between 1 and 2; similar measurements for O2- were taken near pH 10. The results show that, overall, amino acids are relatively unreactive toward both HO2 and O2-. Computed second-order rate constants for their interaction with HO2 range from 101 mol-1s-1 for aliphatic amino acids to about 600 1 mol-1s-1. The second-order rate constants for the interaction of amino acids with O2- are smaller and range from 0.1 to about 20 1 mol-1s-1.


[Modulation of dopaminergic receptor sensitivity in the central nervous system: important parameters in synaptic function regulation]. Modulation in sensitivity of dopamine receptors in the central nervous system are reviewed. Three main types differing by their behavioural and biochemical characteristics are described: -- Disuse hypersensitivity to dopamine agonists, induced by an interruption of dopaminergic transmission, seems to depend on an increased number of post-synaptic dopamine receptors; -- Hyposensitivity to dopamine agonists, induced by an overstimulation of dopamine receptors, could depend on their qualitative or quantitative modifications; -- Behavioural facilitation, elicited by a previous administration of dopaminergic agonists in low dosage, could be associated with an hyposensitivity of dopaminergic autoreceptors. They seem to constitute important parameters in adaptation of synaptic efficacy in physiological as well as pathological states.


Uptake of taurine, GABA, 5-HT, and dopamine by blood platelets in progressive myoclonus epilepsy. The uptakes of four neurotransmitters (taurine, GABA, 5-HT, and dopamine) by blood platelets from patients with degenerative-type progressive myoclonus epilepsy (PME) and from controls were studied using different incubation times and different concentrations. Only the uptakes of taurine differed significantly between patients and controls: patients' uptakes were 70% to 80% of control values at 10, 30, 60, and 120 min of incubation time. Km values were approximately the same, but Vmax values in PME patients were lower, showing quantitative but not qualitative differences in taurine uptake by platelets in PME. These results suggest that a defect or an inhibitory mechanism of some factor needed in the transport or binding of taurine (but not of GABA, 5-HT, and dopamine) is present in PME.


An analysis of 500 cases of equine cryptorchidism. The authors analyse data collected over 23 years from 500 cryptorchid horses. They show that left- and right-sided abdominal cases occur with approximately equal frequency in ponies. Approximately half the right-sided unilateral abdominal cases have the epididymal tail descended while only 20 per cent of the left-sided cases do. These findings are briefly discussed. From their analysis of inguinal cryptorchidism the authors conclude that it is a relatively more complex phenomenon with incidence changing with age as well as breed. Right-sided retention predominates in young ponies, probably being an extreme expression of testicular hypoplasia, but in older ponies and in other types of horse, retention occurs equally on the left and right.


Activities of NAD-specific and NADP-specific isocitrate dehydrogenases in rat-liver mitochondria. Studies with D-threo-alpha-methylisocitrate. The contributions of NAD-specific and NADP-specific isocitrate dehydrogenases to isocitrate oxidation in isolated intact rat liver mitochondria were examined using DL-threo-alpha-methylisocitrate (3-hydroxy-1,2,3-butanetricarboxylate) to specifically inhibit flux through NADP-specific isocitrate dehydrogenase. Under a range of conditions tested with respiring mitochondria, the rate of isocitrate oxidation was decreased by about 20--40% by inhibition of NADP-isocitrate dehydrogenase, and matrix NADP became more oxidized. (a) For mitochondria incubated with externally added DL-isocitrate and citrate, the rate of isocitrate oxidation obtained by extrapolation to infinite alpha-methylisocitrate concentration was approximately 70% of the uninhibited rate in both state 3 and state 4. (b) With pyruvate plus malate added as substrates of citric acid cycle oxidation and isocitrate generated intramitochondrially, a concentration of alpha-methylisocitrate (400 microM) sufficient for 99.99% inhibition of NADP-isocitrate dehydrogenase inhibited isocitrate oxidation in states 4 and 3 by 21 +/- 6% and 19 +/- 11% (mean +/- SEM), respectively. (c) With externally added isocitrate and citrate, the addition of NH4Cl increased isocitrate oxidation by 3--4-fold, decreased NADPH levels by 30--40% and 2-oxoglutarate accumulation by about 40%. The further addition of 600 microM alpha-methylisocitrate decreased the NH4Cl-stimulated isocitrate oxidation by about 40% and decreased NADPH to about 30% of the level prevailing in the absence of NH4Cl; nevertheless, the rate of isocitrate oxidation was still twice as large in the presence of NH4Cl and alpha-methylisocitrate as in their absence. Experiments were also performed with intact mitochondria incubated with respiratory inhibitors to determine additional factors which might affect the flux through the two isocitrate dehydrogenases. (a) In the coupled reduction of acetoacetate by isocitrate, where the rate of reoxidation of reduced pyridine nucleotides is limited by NAD-specific 3-hydroxybutyrate dehydrogenase, 85--100% of the rate of 3-hydroxybutyrate formation was retained in the presence of 400--900 microM alpha-methylisocitrate. (b) In a system where the rate of isocitrate oxidation is limited by the rate of NADPH reoxidation by glutathione reductase, the rate of glutathione reduction extrapolated to infinite alpha-methylisocitrate concentration was from 20--40% of the uninhibited rate. (c) In the coupled synthesis of glutamate from isocitrate and NH4Cl, where the reoxidation of NADPH and NADH can occur via glutamate dehydrogenase, the rate of glutamate production extrapolated to infinite alpha-methylisocitrate concentration was about 60% of the uninhibited rate.


Nuclear-magnetic-resonance study on Met-enkephalin and Met-enkephalinamide. Molecular association and conformation. The 270-MHz 1H and 68-MHz 13C nuclear magnetic resonance spectra of Met-enkephalin (Tyr-Gly-Gly-Phe-Met) and Met-enkephalinamide are analyzed in a variety of solvents. For the dipolar form of Met-enkephalin in (C2H3)2SO solution, significant concentration dependences are found of C-alpha proton chemical shifts, indicating an aromatic ring-current effect in molecular aggregates. An anomalous temperature dependence is observed of the amide proton chemical shift of the Met-5 residue. Furthermore, the chemical shifts of C-alpha protons of the dipolar form are found to depend appreciably on temperature. From the analyses of the temperature dependences together with concentration dependences of C-alpha proton resonances, the dipolar form of Met-enkephalin is found to be in an equilibrium of folded and extended conformations at low concentration in (C2H3)2SO solution. Solvent-composition dependences of the amide and C-alpha proton resonances and carbonyl and alpha-carbon resonances of the dipolar form in 2H2O/(C2H3)2SO solution are consistent with the conformation equilibrium and the association equilibrium. The folded conformation of the dipolar form in (C2H3)2SO solution is stabilized by the intramolecular attraction between the positively charged N-terminal group and negatively charged C-terminal group. The presence of the folded conformation is confirmed by the measurements of Gd(III)-induced relaxation enhancements of C-alpha protons. Nuclear Overhauser effects on the dipolar form are not consistent with the predominant formation of the beta-turn structure with the intramolecular hydrogen bond (Gly-2) C=O . H-N(Met-5). For the dipolar form of Met-enkephalin in 2H2O solution and for the cationic form of Met-enkephalinamide in (C2H3)2SO solution and in 2H2O solution there is no evidence for the formation of folded conformations.


Bone marrow transplantation for severe combined immunodeficiency disease. Reported from 1968 to 1977. Patients who received bone marrow transplantation (= BMT) for the treatment of severe combined immunodeficiency (= SCID), and who were reported in the medical literature from 1968 to 1977, were collected and analysed. Eighteen of these 80 children are still alive, 10 months to 9 years after transplantation. It is thus the first successful form of therapy for this otherwise invariably fatal disease. Fifteen of the 18 survivors received bone marrow cells from HLA and MLC compatible donors; the remaining 3 survivors received grafts from MLC-compatible but HLA-incompatible donors. Bone marrow transplantation is the treatment of choice for SCID when recipient and donor are HLA- and MLC-identical. All patients who received MLC-incompatible grafts died, and bone marrow transplantation for SCID from MLC-incompatible donors should be abandoned. Milt-to-severe graft-versus-host disease (= GVHD) occurred in spite of HLA- and/or MLC-compatibility, with some correlation to the number of cells transplanted. This should preferably be kept below 50 million cells per kilo body weight. Infection was the chief cause of death in all groups. Strict reverse isolation, bowel decontamination and routine pre- and post-transplant Pneumocystis carinii prophylactic treatment are recommended. The clinical picture and laboratory findings of these 80 children before BMT did not differ from non-transplanted SCID patients. Three of the 18 survivors are adenosinedeaminase deficient.


Clinical experiences in the Gambro-preservation unit: analysis of 101 human cadaver kidneys. 101 human cadaver kidneys were preserved by means of hypothermic pulsatile perfusion in the Gambro perfusion unit with human albumin as perfusate. Perfusate flow and some biochemical parameters were assessed during perfusion and correlated with renal function after transplantation. There is a good correlation between perfusate flow and recovery of physiological renal function. LDH released to the perfusate as viability test is of limited value: a direct correlation was only found between LDH activity and perfusion time, and LDH activity and ischemia time. Determination of pH and lactic acid level 1 h after beginning of perfusion is without practical value according to our experience. The quality of albumin in perfusion solution influences the immediate graft function.


Effects of 4 beta-adrenoceptor blocking drugs on blood pressure and exercise heart rate in hypertension. The effects of 4 beta-adrenoceptor blocking drugs on blood pressure and on exercise tachycardia were compared in a within-patient study of patients with uncomplicated essential hypertension. Twelve patients were treated with propranolol, practolol and atenolol and 7 of the same patients also received oxprenolol. Each patient received each drug separately, withdrawing each drug before starting the next, and each patient was titrated to the lowest attainable blood pressure and heart rate with each compound. All 4 drugs caused reductions in both systolic and diastolic blood pressure and in the heart rate induced by exercise. The maximum reduction by each drug in both systolic and diastolic blood pressure was the same. There were small but significant differences in the effects on heart rate between those drugs which had intrinsic sympathomimetic activity and those which did not have this property.


Exercise responses of healthy subjects in the evaluation of cardioselectivity of beta-blockers. The effects of intravenous propranolol, metoprolol, acebutolol and placebo on exercise-induced changes in heart rate and peak flow rate (PFR) have been studied in a group of healthy subjects. The three beta-blockers produced significant and comparable reductions in exercise-induced tachycardia and the magnitude of the reduction was related to the log plasma concentration of each drug. Significant cardiac beta-blockade was detectable for three hours after giving propranolol and for four hours after metoprolol and acebutolol. The exercise-induced changes in PFR were small and variable and were not significantly affected by any of the drugs. We conclude that, contrary to published reports, exercise-induced changes in heart rate and PFR in healthy subjects do not provide a satisfactory test system for assessing the selectivity of beta-blockers.


Neuroleptic receptors: stereoselectivity for neuroleptic enantiomers. In order to identify a pair of neuroleptic enantiomers with the highest stereoselective interaction with neuroleptic/dopamine receptors, the effects of eight pairs of neuroleptic enantiomers were tested on the specific binding of 3H-spiperone to crude homogenates of calf caudate nucleus. The ratios of the Ki values were: (+)-butaclamol/(-)-butaclamol = 3000; dexclamol/(-)-analogue = 151; (+)-isobutaclamol/(-)-isobutaclamol = 146; (-)-CTC/(+)-CTC= 109; (-)-centbutindole/(+)-centbutindole = 20; S(+)-octoclothepin/R(-)-octoclothepin = 11. Thus, the neuroleptic receptor is highly stereoselective for the rigid butaclamol derivatives, but much less so for the flexible neuroleptics. The 3H-apomorphine binding site, however, had a stereoselectivity ratio of only 7 for isobutaclamol, further suggesting that the high affinity sites (i.e. nM) for 3H-neuroleptic binding and for 3H-apomorphine binding are different.


Hallucinogens antagonize histamine H1 receptors of cultured mouse neuroblastoma cells. Hallucinogens were competitive antagonists of histamine at the H1-receptor of cultured mouse neuroblastoma cells. Their rank order of potency at this receptor was similar to that for their potency at eliciting subjective effects in vivo. Comparison with studies of other receptors, however, suggests that no single model of drug--receptor interaction adequately accounts for the known subjective effects of these compounds.


Nigrostriatal lesions enhance striatal 3H-apomorphine and 3H-spiroperidol binding. Following unilateral 6-hydroxydopamine nigrostriatal lesions in rats, the binding of both 3H-apomorphine and 3H-spiroperidol in the striatum is increased. In rats with incomplete lesions or at early time points after lesion, binding is not significantly different from control levels.


Effect of histamine on uterine vasculature in rats. The effects of histamine infusions on the rat uterine vasculature have been studied using the radioactive microsphere technique. Histamine produced a marked uterine vasodilatation which could be partly mimicked by infusion of either the H1-receptor agonist, 2-(2-aminoethyl)pyridine, or the H2-receptor agonist, 4-methyl-histamine. Histamine-induced uterine vasodilatation could only be reduced significantly by administration of a combination of the H1- and H2-receptor antagonists mepyramine and metiamide but not by either antagonist given alone. It was concluded that histamine-induced vasodilatation in the rat uterus is mediated by both H1- and H2-receptors.


The mechanism of the clonidine-induced reduction in peripheral parasympathetic submaxillary salivation. The mechanism of the clonidine induced reduction in submaxillary salivation evoked by electrical stimulation of the chorda tympani was investigated in anaesthetised cats. This effect of clonidine was found to be dose and frequency dependent. In addition to clonidine, tramazoline, also a preferential presynaptic alpha-adrenoceptor agonist, produced a reduction in electricallly evoked salivation. Methoxamine, noradrenaline and naphazoline, which are less potent presynaptic alpha-receptor agonists, caused increases in salivation. Phentolamine only partially antagonized the decrease in salivation produced by clonidine whereas it was virtually abolished by yohimbine. Clonidine increased salivation evoked by intra-arterial injections of carbachol. These findings suggest that clonidine reduces peripheral parasympathetically evoked submaxillary salivation by activation of presynaptic alpha-adrenoceptors which inhibit cholinergic transmission.


Digitalis drugs and vulnerability to ventricular fibrillation. The effect of acetylstrophanthidine (AS), a rapid-acting digitalis-like agent, on the ventricular fibrillation (VF) threshold was examined in normal and denervated chloralose-anesthetized dogs. In neurally intact dogs an intravenous bolus of AS (0.075 mg/kg) increased the VF threshold up to a maximum 50% (P less than 0.01) within 30 min after injection. The augmented VF threshold following intravenous administration of AS was not altered by vagotomy. Bilateral stellectomy in vagotomized dogs, as well as carotid sinus and aortic arch denervations, however, prevented the AS induced increase in VF threshold. In neurally intact dogs beta-adrenergic blockade with propranolol (0.25 mg/kg) precluded AS effects. These data suggest that the increase in the VF threshold resulting from AS administration in the normal canine ventricle is due to withdrawal of sympathetic tone mediated via the baroreceptor reflex. The direct effect of AS on the myocardium is to decrease the VF threshold.


Inhibitory effect of kanamycin on evoked transmitter release. Reversal by 3,4-diaminopyridine. The effect of kanamycin (Kn) on evoked transmitter release was examined in frog end-plates in vitro. By a presynaptic action, Kn (0.02 to 1 mM) significantly reduced the amount of acetylcholine liberated by nerve stimulation. In addition to its presynaptic effects, Kn (0.96 mM) decreased the size of the miniature end-plate potentials possibly by acting at the postsynaptic level. 3,4-Diaminopyridine (4.5 microM) reversed the presynaptic effects of Kn but did not modify its postsynaptic action.


Otolithic-acoustic interaction in the control of eye movement. In order to examine otolithic contribution to eye movements ten subjects were asked to track either a moving acoustic target or a stationary target during subject linear motion on a cart. The relative displacement between the subject and the target was the same in the two situations. Recordings of eye movements during subject lateral acceleration in the dark without any task, or with the task of tracking an imagined stationary target were made as a control. The frequencies ranged between 0.15 and 0.3 Hz and peak acceleration between 0.55 and 1.2 m/s2. No lateral eye movements (L-nystagmus) were recorded in the dark. Only saccadic eye movements were recorded during the tracking of a moving acoustic target. Slow eye movements interspersed by saccades were observed when the moving subject tracked an imagined or an acoustic stationary target. Contribution of the slow phase to tracking was more important in the presence of an acoustic target than in the presence of imagined target. The results are interpreted in terms of an otolithic contribution to the central reconstruction of the acoustic target velocity, or in terms of an adaptive control of the otolithic-ocular reflex gain. A conceptual model accounting for these interpretations is proposed.


Lack of effect of neurotransmitters on cyclic AMP phosphodiesterase activity in an insect CNS. The inhibition of cyclic nucleotide phosphodiesterase from the nerve cord of Manduca sexta was studied using theophylline as a model compound. 11 putative neurotransmitters had no effect on enzyme activity.


Haemoglobin Bohr effect and lactic acid content of the blood of 2 water-snakes with different degrees of aquatic adaptation. H. modestus, a water-snake with morphological respiratory adaptation to its habitat, presents haemoglobins with a lower Bohr effect than those of L. miliaris, an aquatic snake without such respiratory adaptations. The difference in blood lactic acid content of the 2 snakes submitted to mechanical stimuli appears to be compatible with the properties of their haemoglobins.


gamma-Glutamyltranspeptidase (GGTP) and cytochrome P-450 after portacaval shunt in the rat. The increased hepatic activity of gamma-glutamyltranspeptidase after portacaval shunt is due to derepression of a fetal enzyme rather than to an induction mechanism.


Presumptive identification of aminoglycoside antibiotics by the pH susceptibility disc agar-diffusion method. Using the pH (buffered) sensitivity discs for the agar-diffusion bioassay of aminoglycoside antibiotics, characteristic response curves were obtained. Since the nature of the activities observed are structure-related, this method can serve as a useful aid for primary identification of members of this class of antibiotics.


Relationship between the pentose phosphate shunt and methemoglobin reductase activity in human erythrocytes: Effect of aging on methemoglobin reductase activity. The increase in methemoglobin reductase activity in human erythrocytes upon incubation with inosine, phosphate, pyruvate occurs only in the presence of methylene blue. No difference in activity of the methemoglobin reductases was observed between enzyme extracts of fresh cells and aged cells.


Differential developmental pattern of acid and alkaline phytase and phosphatase activities in rat intestine. Rat intestine was found to show a distinct acid phytase activity (pH optimum 4.7) in addition to that of an alkaline phytase (pH optimum 8.0). The phytase and phosphatase activities were found to differ in their developmental pattern and responded differentially to some inhibitors. Thus the two activities seem to be due to two independent enzymes and are not the activity of a nonspecific phosphatase as has been suspected formerly.


[Effect of tranquilizers on the interaction processes of positive and negative reinforcement systems]. The tranquilizers diazepam, nitrazepam, chlordiazepoxid and elroquil produce diverse effects on conflict interaction of the systems of brain reinforcement subjected to simultaneous electric stimulation. The anxiolytic action of diazepam and chlordiazepoxid on behavior is determined by displacement of the activity balance of the systems of reinforcement to the system of positive reinforcement. Prevalent activity of the system of punishment in the action of elroquil accounts for its lower tranquilizing effect.


[Effect of butyrophenone derivatives on D-serotonin reactive structures]. Droperidol, haloperidol and azabutyron inhibit the reactions of rabbit aortal stria caused by stimulation of D-type serotonine receptors. Droperidol appears most active in this respect. Its antiserotonine properties are characterised by certain selectivity. The capacity of droperidol for protection of D-receptors against irreversible dibenamine blockade suggests its indirect interaction with D-receptors.


Antagonism between dopaminergic and neuroleptic drugs. I. Acute administration. In this paper we report our results concerning the antagonism between dopaminergic (bromocriptine, apomorphine, piribedil) and neuroleptic (haloperidol, chlorpromazine, reserpine, clotiapine) drugs on the eeg and behaviour of rabbits. The Monnier and Gangloff stereotaxic method was used in order to record cortical and deep structures. The use of neurophysiologic methods also enabled us to verify the magnitude and modes of the antagonism between the two types of drugs. Particularly, the dissociation between eeg and behavioural effects of this antagonism is discussed; this fact seems to confirm the hypothesis that dopaminergic drugs have a double point of attack in the CNS.


Antagonism between dopaminergic and neuroleptic drugs. II. Chronic administration. In this work the eeg and behavioural effects obtained after the administration of dopaminergic drugs (bromocriptine, apomorphine, piribedil) in rabbits chronically pretreated with haloperidol, chlorpromazine, clotiapine, are shown. The Monnier and Gangloff stereotaxic method was used. The aim of the study was to verify receptor supersensitivity by neurophysiologic methods. The neurophysiologic pattern of receptor supersensitivity induced by long-lasting treatment with neuroleptic drugs and its peculiarity are discussed.


[Comparative characteristics of the effect of noninhalational narcotics on the reflex mechanisms of blood circulation regulation]. It has been shown in experiments on cats with intact brain, as well as on decerebrated and spinal animals that chloralose, sombrevine and viadril exert no pronounced effect on initial electric activity in the renal nerve or baroreceptor inhibition of the neurogenous vascular tone, but inhibit vasomotor responses at stimulation of highly liminal afferent fibers of the cerebrospinal nerves. In animals with intact brain, sodium hydroxybutyrate inhibiting baroreceptor reflexes enhanced vasomotor reactions caused by activation of cutaneous and visceral nerves.


[Toxicity of lithium salts in combined use with neuroleptics]. Experiments on white mice showed that in combined administration of LD16, LD50 or LD84 of aminazin, triphtazine or haloperidol with the same doses of lithium carbonate, chloride or hydroxybutyrate, the lethal dose exceeded the total lethal dose in the event the drugs were administered alone. Non-lethal doses of the lithium salts produced no effect on LD16, LD50 and LD84 of triphtazine and haloperidol, but non-lethal doses of these neuroleptics potentiated the action of lethal doses of the lithium salts. Haloperidol is an exception to the rule since it did not exert such action with respect to lithium chloride. Aminazin and lithium salts increased also each other's toxicity in instances where one of the drugs was administered in a non-lethal dose, whereas the other in a lethal one.


Immunocytochemical localization of neuronal antigens: tyrosine hydroxylase, substance P, [Met5]-enkephalin. Neuronal antigens can be demonstrated histologically by numerous direct and indirect immunocytochemical techniques in which a specific antibody is identified by a marker compound such as fluorescein isothiocyanate, ferritin, or horseradish peroxidase. One of the more sensitive methods for the light and electron microscopic localizations of antigens in sections of tissue is the peroxidase-antiperoxidase (PAP) technique. The experimental procedures and the results obtained using this technique for the localization of the catecholamine synthesizing enzyme, tyrosine hydroxylase, are described. The cellular and ultrastructural localization of the enzyme is demonstrated in perikarya, processes, and terminals of catecholaminergic neurons in rat brain. The immunocytochemical localization of tyrosine hydroxylase is compared to the localization of two peptides, substance P and [Met5]-enkephalin, in the A2 region of the medulla. These studies suggest that a synaptic interaction exists between the catecholaminergic neurons and neurons showing positive immunoreactivity for the peptides. The limitations of the PAP immunocytochemical technique are also discussed in relation to the immunocytochemical localization of tyrosine hydroxylase and other antigens.


Photomyoclonic seizures in the baboon, Papio papio. The inborn seizure response of Papio papio to intermittent light stimulation has been reviewed as a model of human epilepsy. The electrographic and clinical features have been described and useful methodology has been outlined. A diurnal cyclicity in seizure responsiveness has been described with greatest seizure severity at 8 AM in parallel with a rise in urinary output of cortisol. Hormonal influences on the seizure response have been described for ethinyl estradiol, thyroxin, and triiodothyronine. Evidence regarding neurotransmitter involvement has been reviewed. Data regarding use of the animal for anticonvulsant testing in single and chronic doses has been discussed. Particular advantages of the model for study of age-related drug effects and the assessment of the effects of chronically administered anticonvulsant agents on learning and memory have been described.


A double-blind comparison of prazepam with diazepam, chlorazepate dipotassium and placebo in anxious out-patients. The study compared prazepam with diazepam, chlorazepate dipotassium, and placebo in the treatment of anxious out-patients. Patients were screened for participation in the study to be sure they met the criteria for inclusion. Patients were excluded if they had complicating physical or mental problems. All patients signed an informed consent. Seventy-three patients entered the study, thirteen did not complete at least two weeks of treatment and were not used in the data analysis. Of these thirteen, ten did not return and were lost to follow-up, tow entered the hospital for reasons unrelated to the drug study, and one patient on diazepam was terminated because of increased anxiety. Six patients were used in the data analysis, thirty-six males and twenty-four females with an age range of 21-61 years. Side-effects were minimal. Drowsiness was reported by two people in the placebo group, one taking chlorazepate dipotassium, three on prazepam and one on diazepam. One diazepam patient reported nausea and vomitting. Scores on the Zung Self-Rating Scale for Anxiety showed all three drug groups to be superior to placebo. The Hopkins Symptom Check-list found prazepam and diazepam to be superior to placebo and chlorazepate. No differences among the groups were found in the Hamilton Anxiety Scale. Prazepam may offer advantages over the other available benzodiazepines since it may be more readily absorbed than chlorazepate and has less side-effects than diazepam.


Effect of parental aspirin on the gastric mucosal barrier in the rat. The purpose of the present study was to determine in the rat whether parenteral aspirin, like topical aspirin, injures the gastric mucosa by diffusely disrupting the gastric mucosal barrier to hydrogen ion back-diffusion. Back-diffusion studies, including the ion fluxes and lumenal potential difference, were performed in control situations and either 0.5 or 4 h after the intraperitoneal administration of sodium acetylsalicylate. Gastric mucosal lesions were scored. After 0.5h, lesions developed but the barrier was intact. However, after 4 h, lesion formation was more severe and changes characteristic of diffuse barrier disruption, fall in potential difference and increased loss of hydrogen ion occurred. Since lesions occurred before evidence of diffuse barrier disruption could be detected, we conclude that in the present model diffuse barrier disruption is a consequence rather than a cause of lesions.


Vasoactive intestinal polypeptide: measurement, distribution and putative neurotransmitter function. Vasoactive intestinal polypeptide (VIP) is a highly basic octacosapeptide isolated from porcine small intestine. VIP was originally considered to be a gut hormone, but radioimmunochemical and immunohistochemical studies have revealed that VIP has a widespread distribution localized in neurons. VIP-containing neurons are present in the central nervous system including the cerebral arteries, the digestive tract, the genitourinary tract and the adrenal glands. In the nerve terminals VIP is localized in synaptic vesicles. VIP fulfils a number of criteria to be a neurotransmitter both in central and peripheral nerves. Whilst the role of VIP in the central nervous system is unknown, it is likely that VIP is the mediator of gastrointestinal and pancreatic functions, which are controlled by non-cholinergic, non-adrenergic nerve fibres.


[Clinical and biological aspects in patient with pH-triggered implanted pacemaker (author's transl)]. The Authors have selected the variations of blood pH to drive the pacing rate according to the new biological balance created by exercise. The clinical tests performed on the patients who have had a pH-triggered pacemaker implanted one year previously demonstrated that: a) during physical exercise there is an increase of cardiac rate triggered by the pacemaker, comparable with that noted when sinus rhythm is present; b) situations causing an increased production of cathecolamines and thus a pH variation--Cold Pressor Test, Ischaemic Test, as well as emotional stress--cause an increase of the stimulation rate of pH triggered pacemaker.


Diminished activities of fatty acid synthesis enzymes in insulin-resistant adipocytes from spontaneously obese rats. Acetyl coenzyme A carboxylase and fatty acid synthetase activities were studied to determine the biochemical basis of the markedly impaired capacity of fat cells from spontaneously obese, old rats to convert glucose to fatty acids relative to cells from lean, young rats. Michaelis constants for the substrates of both enzymes were similar in large and small adipocyte homogenates. In contrast, Vmax values were over 80% less in homogenates from large relative to small cells on a per cell basis. Long-term dialysis or the presence of albumin during the assays failed to restore the activities of these enzymes in homogenates of large fat cells. The combination of equal volumes of homogenates from the two cell types resulted in carboxylase and synthetase activities intermediate between activities found in the two homogenates alone. Therefore, the presence of endogenous allosteric inhibitors does not appear to account for the markedly blunted fatty acid synthesis enzyme activities in large fat cells. These results suggest that the fatty acid synthesis impairment, which is a primary defect in the insulin resistance of the large cells, is at least partly due to diminished cellular contents of acetyl coenzyme A carboxylase and fatty acid synthetase.


The effect of acute metabolic acidosis on plasma cortisol, renin activity and aldosterone. The effect of metabolic acidosis on the renin-aldosterone system remains unclear. In the present study anesthetized mongrel dogs (n = 19) were infused at similar rates with 0.45% NaCl (controls), HCl or NH4Cl (2.5mEq/kg) for 1--3 h. The induced metabolic acidosis in the two experimental groups was not associated with increases in plasma renin activity. Plasma cortisol (as a marker for ACTH secretion) and serum potassium concentration increased in both HCl- and NH4Cl-treated animals. Plasma aldosterone increased after 30 min in the HCl group and 60 min in the NH4Cl group and did not change in controls. These findings demonstrate that metabolic acidosis induced by HCl or NH4Cl is associated with increased aldosterone production without concomitant changes in plasma renin activity.


Myeloperoxidase-hydrogen peroxide-chloride antimicrobial system: effect of exogenous amines on antibacterial action against Escherichia coli. Exogenous ammonium ions (NH(4) (+)) and amine compounds had a profound influence on the antibacterial activity of the myeloperoxidase-hydrogen peroxide-chloride system against Escherichia coli. The rate of killing increased in the presence of NH(4) (+) and certain guanidino compounds and decreased in the presence of alpha-amino acids, polylysine, taurine, or tris (hydroxymethyl) aminomethane. Myeloperoxidase catalyzed the oxidation of chloride to hypochlorous acid, which reacted either with bacterial amine or amide components or both or with the exogenous compounds to yield chloramine or chloramide derivatives or both. These nitrogen-chlorine derivatives could oxidize bacterial components. Killing was correlated with oxidation of bacterial components. The rate of oxidation of bacterial sulfhydryls increased in the presence of the compounds that increased the rate of killing and decreased in the presence of the other compounds. The reaction of HOCl with NH(4) (+) yielded monochloramine (NH(2)Cl), which could be extracted into organic solvents. The N-Cl derivatives of bacterial components or of polylysine, taurine, or tris(hydroxymethyl)aminomethane could not be extracted. The effect of NH(4) (+) on killing is attributed to the ability of NH(2)Cl to penetrate the hydrophobic cell membrane and thus to oxidize intracellular components. Polylysine, taurine, and tris(hydroxymethyl)aminomethane formed high-molecular-weight, charged, or polar N-Cl derivatives that would be unable to penetrate the cell membrane. These results suggest an important role for leukocyte amine components in myeloperoxidase-catalyzed antimicrobial activity in vivo.


Immunization of calves against enterotoxigenic colibacillosis by vaccinating dams with purified K99 antigen and whole cell bacterins. Pregnant cattle were either vaccinated subcutaneously with (i) a suspension of purified Escherichia coli K99 pili, (ii) a Formalin-killed whole cell bacterin containing enterotoxigenic E. coli strain B44 (O9:K30;K99:H-), or (iii) a bacterin containing six different strains of bovine enterotoxigenic E. coli (multiple-strain bacterin), or were left as nonvaccinated controls. After birth, calves were allowed to nurse their dams and, at 12 to 14 h of age, were challenged orally with 10(11) cells of enterotoxigenic E. coli strain B44. Colostral antibody titers were determined against K99, K30, and O9 antigens of B44. In the nonvaccinated control group, 9 of 10 calves developed diarrhea and died within 24 to 72 h. Similarly, all six calves in the multiple-strain bacterin group developed diarrhea and four died. In contrast to calves in the two groups mentioned above, calves nursing cows vaccinated with either purified K99 or the homologous whole cell bacterin were protected against fatal diarrhea. There was a highly significant correlation (P less than 0.0005) between protection against fatal diarrhea and K99, but not K30 or O9 colostral antibody titers. Vaccination of cows with either purified pili or whole cell preparations containing sufficient K99 antigen may provide a means of preventing enterotoxigenic colibacillosis in calves.


Lactoperoxidase binding to streptococci. There have been conflicting reports regarding the binding of lactoperoxidase to bacterial cell surfaces. We describe here the effects of cell-bound lactoperoxidase on acid production by suspensions of Streptococcus mutans (NCTC 10449) in the presence of hydrogen peroxide and thiocyanate. Saline suspensions of log-phase bacteria were treated with 0.1 mg of lactoperoxidase per ml and were then washed thoroughly. The addition of hydrogen peroxide and thiocyanate markedly reduced the acid production of these lactoperoxidase-treated bacteria but had no effect on the acid production of untreated controls. After a 3-h incubation in saline, the lactoperoxidase-treated bacteria produced acid in the presence of hydrogen peroxide and thiocyanate at the same rate as untreated bacteria. These observations suggest that lactoperoxidase is initially bound to the cell surface in an enzymatically active form at a concentration sufficient to inhibit acid production. The lactoperoxidase is slowly degraded or desorbed as the bacteria stand in saline suspension.


Purification and crystallization of fimbrial hemagglutinin from Bordetella pertussis. A procedure to purify and crystallize fimbrial hemagglutinin from Bordetella pertussis is described. Redissolved crystals had the same specific activity as the original, purified solution of fimbrial hemagglutinin. About 97% of the weight of washed crystals was accounted for by amino acids.


Adherence of erythrocytes to Mycoplasma pneumoniae. The human pathogen Mycoplasma pneumoniae adheres to a variety of cells, including erythrocytes. A hemadsorption technique was developed to quantitate adherence by photometric measurement of lysates of erythrocytes that attached to sheets of M. pneumoniae grown in cups of Linbro plates. Attachment of sheep erythrocytes (SE) increased with higher ionic strength, was unaffected by minor pH variations (6 to 9), and was blocked by anti-M. pneumoniae antiserum, but was not inhibited by a variety of sugars, amino acids, and bovine serum albumin. The reaction was time and temperature dependent. The temperature curve showed peaks at 14 and 28 degrees C with untreated SE but only one peak at about 38 degrees C with glutaraldehyde-treated SE. The temperature dependence indicated involvement of either metabolic or membrane activities in the binding process. Trypsin treatment of the M. pneumoniae sheet abolished adherence of SE but was only partially effective with human erythrocytes and noneffective with rabbit erythrocytes. The binding capacity of the mycoplasma cells for SE was restored by incubation in growth medium for 3 to 4 h; this restoration was inhibited by 10 mug of chloramphenicol per ml. Neuraminidase treatment of SE removed their attachment capacity but had no effect on attachment of rabbit erythrocytes and only a slight effect on attachment of human erythrocytes. Pretreatment of M. pneumoniae with neuraminic acid partially blocked the adherence of SE, whereas rabbit erythrocyte attachment was not affected. Attached SE could be detached by trypsin, but not by neuraminidase. For human and rabbit erythrocytes, the results suggest binding mechanisms other than the interaction between neuraminidase-sensitive receptors and protein-containing binding sites shown for SE.


Effect of growth conditions on the formation of extracellular lipoteichoic acid by Streptococcus mutans BHT. Streptococcus mutans BHT was grown in a chemostat with glucose limitation and at defined dilution rates and pH values. Lipoteichoic acid was estimated by determining the ability of dilutions of culture fluid to sensitize erythrocytes. The greatest amounts of extracellular lipoteichoic acid were produced by organisms growing at a low dilution rate and at pH 6.0 or 6.5. To enable a more accurate estimation of the total amount of extracellular material, rocket immunoelectrophoresis was employed. These results confirmed that the greatest amounts of reactive material were produced by slow-growing organisms, although there were discrepancies between these results and those obtained by hemagglutination. The extracellular material was fractionated by column chromatography and membrane ultrafiltration to yield a lipoteichoic acid-containing fraction and a presumptive deacylated lipoteichoic acid fraction. The relative proportions detected by rocket immunoelectrophoresis differed with the growth conditions, particularly the dilution rate. Analysis of the phenol-extracted cellular material also indicated the presence of deacylated lipoteichoic acid, although less than in the culture fluid.


[EEG changes during clozapin administration compared to other neuroleptic agents. Controlled case study in a particular patient]. A hyperactive mentally retarded patient receiving clozapin and other major tranquilizers had an unexpected seizure. The EEG revealed severe pathological patterns which disappeared after discontinuation of clozapin and could be reproduced as a function of clozapin medication. Other major tranquilizers had no particular effects. This study demonstrates how we determined whether clozapin or other major tranquilizers had seizure-promoting effects in a particular patient.


Drug induced dyskinesia: a critical review. Tardive dyskinesia (TD) has been reported to occur after the long term administration of neuroleptics. Its prevalence has been reported to vary from 0.5-56%. However, no clear relationship is established between a particular neuroleptic, its dosage and duration of administration and the diagnosis and occurrence of TD. Neuropathological investigations have not provided any definitive lessons. in addition, TD can be produced by a number of drugs of different chemical classes. Similarly, the evidence for dopaminergic hypersensitivity is equivocal. The only definitive feature seems to be an individual predisposition, the nature of which needs to be elucidated. Of course, basic to any future research into new insights regarding etiology, the fundamental problem of definition and identification based on the accepted definition are most essential. This solid foundation is necessary for the resolution of any conflicting results that may be reported in the future.


[Discontinuation of neuroleptics in chronic schizophrenics. I. Summary of the literature]. Based on the available publications on the discontinuation of antipsychotic drug treatment in chronic schizophrenic patients the following conclusions can be drawn: (1) About 50% of chronic schizophrenic patients develop a psychotic relapse after discontinuation of antipsychotic drug treatment. (2) The risk for a psychotic relapse after neuroleptic withdrawal seems to be less pronounced in older patients with a long duration of illness and hospitalization who are treated with a rather low maintenance dosage of antipsychotic drugs. (3) For the individual patient the effects of discontinuation are only predictable based on earlier results of an individual termination of his antipsychotic drug treatment.


Kawasaki's disease and infantile polyarteritis nodosa: is Pseudomonas infection responsible? Report of a case. A nineteen-month-old child presented with a febrile illness, skin rash, painful swelling of the joints, lymphadenopathy and hepatosplenomegaly. Pseudomonas was cultured from the blood during life and, subsequently, at autopsy. Autopsy revealed a generalized panarteritis involving the coronary, retroperitoneal and pulmonary arteries with thickening of arterial walls and narrowing of the lumina. Thrombi and foci of necrosis and infarcts were found in many organs. Numerous bacilli were present in fresh lesions, but not in the organizing lesions. Periodic acid-Schiff-positive deposits were found in occasional macrophages, in walls of affected vessels, in the marginal sinuses of lymph nodes and diffusely in epicardial and retroperitoneal adipose tissue. The findings suggest that some or even all cases of Kawasaki's disease and infantile polyarteritis nodosa may be caused by Pseudomonas sepsis. It is also suggested that the vasculitis and paucity of inflammatory reaction in many cases of Pseudomonas sepsis might be related to the fact that many strains of Pseudomonas produce high-molecular-weight levan (or another polysaccharide). This compound is known to inhibit the inflammatory reaction and to increase bacterial pathogenicity.


Treatment of delirium--a reappraisal.

Treatment of delirium--a reappraisal. Delirium is a frequently encountered clinical syndrome which can pose serious problems for the physician and patient. Numerous etiological possibilities exist, and each case is usually associated with multiple causal factors. Although the pathophysiology is poorly understood, the clinical presentation is marked either by stupor and hypoarousal or agitation and hyperarousal. Both types of delirium must be treated by searching for and correcting reversible causative factors. In addition, medication may be quite efficacious in managing the clinical aspects of agitated delirium. Most cases of agitated delirium are either of the "sensory overload" or "sensory deprivation" type. The drug treatment of each is discussed with reference to their respective central nervous system physiological correlates.


Fish species identification by thin layer isoelectric focusing. Conventional electrophoretic techniques generally lack the resolution and reproducibility needed for the reliable identification of fish species. Variations in stabilizing media composition, sample application technique, separation time, applied voltage or current, and the analyst's skill all affect the protein pattern. Thin layer polyacrylamide gel isoelectric focusing (TLIEF), a high resolution protein separation technique, has been applied to the identification of fish species. Sarcoplasmic proteins are separated according to their isoelectric points in a stable, reproducible pH gradient. Protein patterns for 12 species of fish are compared in 4.0% polyacrylamide gels with pH 4.0--6.0 and pH 3.5--10 gradients. Similar patterns are shown in commercially prepared 5.0% polyacrylamide gels with pH 4.0--6.5 and pH 3.5--9.5 gradients (LKB PAG plates). The protein patterns are reproducible in each pH gradient and also correlate well between user-prepared and commercially prepared gels. The inherent high resolution and excellent reproducibility of TLIEF should allow the positive identification of fish species without the costly procedure of using known species as standards.


Identification of species in cooked crabmeat by thin layer isoelectric focusing. Thin layer polyacrylamide gel isoelectric focusing (TLIEF) is described for characterizing the species-specific, heat-denatured proteins of 8 species of crab: red (Geryon quinquedens), rock (Cancer irroratus), Jonah (Cancer borealis), blue (Callinectes sapidus), king (Paralithodes camtschatica), snow (Chionoectes spp.), European edible (Cancer pagurus), and dungeness (Cancer magister). Protein pattern differences are shown not only among species, but also between 2 modes of heat processing of the crabmeat. Individual variation within the species as to sex, size and maturity, length of frozen storage, and body parts chosen for sampling do not alter the species banding pattern. The reproducible species-specific fingerprint obviates the need to analyze authenticated samples simultaneously with the unknown crabmeat.


Determination of virginiamycin in feeds. Virginiamycin was extracted from the feed by ethanol-pH 2.5 phosphate buffer (1 + 1). The pH during extraction was adjusted (when necessary) to between 4 and 5. Sample dilutions and the standard dose response line were prepared to contain ethanol pH 6 phosphate buffer (2 + 8), and the test organism was Sarcina lutea. Three feeds (a poultry ration, a swine finishing ration, and a swine starter ration) showed virginiamycin recovery of 88.8--108.9% when standard solutions were added at concentrations of 4.54--90.8 g/ton. The coefficient of variation (4--20%) was larger for low potency feeds (10 g/ton) compared to the higher feeds (100 g/ton). Similarly, excellent recovery was obtained when the swine starter feed was fortified by a commercial premix. Amprolium, roxarsone, and monensin can be present at 20 times the concentration of virginiamycin with little or no interference in the antibiotic determination. Lasalocid at 10 times the concentration of virginiamycin caused a slightly positive bias (recovery, 107.4%).