[Relationship between the characteristics of the acid stimulus and the impulse activity of medulla oblongata neurons in Cyprinus carpio carp]. In experiments on immobilized carps, by means of extracellular recordings, studies have been made of the neuronal activity of the facial lobe in the medulla evoked by stimulation of skin chemoreceptors of the mouth opening with hydrochloric and cytric acids. Responses of the neurons to these stimuli exhibit both similarities and differences. Composing across-neuron patterns, some aspects of coding of quality and intensity of chemical stimulus in fish were elucidated. Particularly it was shown that at low concentrations of acids, in neuronal coding of the stimuli the key role is played by qualitative peculiarities of the latter, but not by the level of pH.


[Isolation and several properties of the glyceraldehyde-3-phosphate dehydrogenase from the muscles of the lamprey Lampetra fluviatillis]. Procedure for isolation of electrophoretically homogeneous, crystalline glyceraldehyde-3-phosphate dehydrogenase from lamprey muscles is described. Amino acid composition of the enzyme was investigated and compared with that of the same dehydrogenase from other sources. With respect to its secondary structure and kinetic parameters, the lamprey enzyme does not significantly differ from those of other animals. Activation energy for the lamprey enzyme is lower than for the same enzyme from endothermic animasl. "Temperature modulation" of Michaelis constant described in the literature, was not confirmed for the lamprey enzyme in the range of physiological pH values.


[Molecular evolution of glycogen phosphorylase and aminotransferases of vertebrate muscle tissue]. Comparative biochemical studies on phosphorylase b, aspartate aminotransferase and alanine aminotransferase in muscles of various vertebrates (the lamprey Lampetra fluviatilis, dogfish Squalus acanthias, rays Dasyatis pastinaca and Raja clavata, teleosts Scorpaena porcus, Spicara smaris, Esox lucius, Tinca tinca, Abramis brama, Lucioperca lucioperca, Cyprinus carpio, Salmo ischchan, frog Rana temporaria, tortoise Testudo horsfieldi) revealed some peculiarties of their molecular evolution. It was shown that isoenzyme PH-II, which comprises in most on the investigated lower vertebrates the main bulk of phosphorylase b, disappears in evolution of the type. Isoenzyme PH-I which is found in fisches in small amounts, increases in evolution becoming the sole form of phosphorylase b in skeletal muscles of endothermic animals. Mitochondrial and cytoplasmic isoenzymes of aspartate aminotransferase were found in all the vertebrates studied. Cytoplasmic isoenzyme from ectothermic and endothermic animals does not differ significantly, whereas the mitochondrial one undergoes considerable changes in the evolution of vertebrates.


Purification and properties of L-asparaginase EC-2 from Escherichia coli 055:B5. 1. L-Asparaginase has been isolated from aerobically grown Escherichia coli 055:B5 and purified about 140-fold in a three-step procedure involving acidification to pH 4.5, ammonium sulphate fractionation and column chromatography on DEAE-Sephadex A-50. The activity of the preparation is 140 U/mg protein. 2. The enzyme acts within a broad pH range (pH 5-9) and is affected neither by PCMB, N-ethylmaleimide nor metal ions. 3. Molecular weight of the isolated asparaginase is 130 000.


Increased serum prolactin in diabetic ketoacidosis; correlation between serum sodium and serum prolacting concentration. In 8 patients with diabetic ketoacidosis, serum prolactin was measured and found to be elevated (24.8 +/- 10.2 ng/ml, mean +/- SEM). After correction of the ketoacidosis, the prolactin level decreased to 10.9 +/- 6.4 ng/ml (normal range men 4.9 +/-0.8, women 5.1 +/- 1.6 ng/ml). The scatter of prolactin values was wide. A study of the correlation between the serum prolactin values and chemical parameters that are altered in diabetic ketoacidosis was therefore undertaken. Serum prolactin values did not correlate well with the serum bicarbonate concentration or serum osmolality. However, a significant negative correlation between log serum prolactin concentration and serum sodium concentration was demonstrated (r = -0.61, P less than 0.01). It is suggested that serum prolactin may possible participate in sodium retention in man as has been demonstrated in studies on animals.


Characterization of human ovarian oestradiol-17 beta oxidoreductase activity. Oestradiol-17 beta oxidoreductase activity, which catalyzes the interconversion of oestrone and oestradiol, was investigated in preparations of human ovaries. The enzyme activities were localized primarily in the 105,000 X g supernatant fraction; dialyzed supernatant preparations were used in subsequent studies. The pH optima were 6.9 for reduction and 8.1 for 17 beta-dehydrogenation. The apparent Michaelis constants for oestrone and oestradiol were 1 X 10(-7) M and 5 X 10(-7) M, respectively. The enzyme activity was present with either NADP(H) or NAD(H), though (NADP(H) were the preferred cofactors. Non-aromatic steroids androstenedione, dehydroepiandrosterone, testosterone and 5-androstene-3beta,17beta-diol were poor substrates for the enzyme preparation. Methylation of the phenolic hydroxyl of oestrone and oestradiol resulted in slightly enhanced activities. The sulfhydryl reagent, N-ethylmaleimide, inhibited the reduction of oestrone. A dialyzed supernatant preparation retained approximately 79% of the original enzyme activity when stored at -20 degrees C for 6 weeks.


Pituitary LH and FSH and testosterone secretion in infants with undescended testes. Twelve male infants with undescended testes (5 bilaterally, 7 unilaterally) were studied between the ages of 1 week and 11 months. As in older pre-pubertal cryptorchid boys, a significant decrease of the LH response to LH-RH test was found, while basal plasma levels of gonadotrophins and FSH response to LH-RH were normal. Plasma testosterone levels were in the normal range, and Leydig cells responded to stimulation by HCG, the degree of this response being significantly and positively correlated to the LH peak elicited by LH-RH. It may be concluded that some early defect of the pituitary-Leydig cell axis is associated with undescended testis.


Postoperative synovial fluid. Metabolic response to meniscectomy or synovectomy. The metabolic response of synovial tissue to surgery was investigated by synovial fluid analysis after two types of operations, medial meniscectomy and synovectomy. Analyses of intra-articular fluid were also performed in non-operated patients with traumatic effusion or chronic synovitis in the knee. It was found that the knee joint metabolism in chronic synovitis is shifted towards anaerobic glycolysis in both operated and non-operated patients whereas meniscectomized and traumatized knees are more capable of maintaining oxidative metabolism. The data also demonstrate that one of the main reasons for decreased oxygen supply on the articular surface after meniscectomies or synovectomies is excessive intra-articular effusion which, according to earlier investigations, produces pressure in the joint cavity and inhibits local capillary circulation.


Infantile polyarteritis and Kawasaki disease. Polyarteritis in infancy is very rare, difficult to diagnose and invariably fatal. A 6-month-old girl who presented with a prolonged unexplained fever and was subsequently demonstrated at post-mortem examination to have polyarteritis is described. The combination of polyarterits with some unusual presenting features suggests that the case described is one of the Mucocutaneous Lymph Node Syndrome (M.L.N.S.) or Kawasaki Disease. Polyarteritis and Kawasaki Disease are discussed with reference to the case described.


[Behavior therapy and sex therapy].

[Behavior therapy and sex therapy]. The author attempts to situate sextherapy of Masters and Johnson in relation to behaviour therapy in indicating the principles elaborated by old behaviour therapy and its most recent developments which are at the origin of sextherapy. He also considers the problem of indications and complementary relation which can be comprehended between these approaches and the psychoanalytical approach.


Hyperthermic tumour-cell devitalization in vivo. A review of the morphologic, biochemical and clinical effects of hyperthermia on malignant cells indicates the presence of two principally different heat-induced alterations. (1) A 'destructive' lysosomal dependent cytoplasmic reaction dominates the tumour-cell devitalization in vivo, probably influenced by the characteristic tumour cell environment. (2) 'Repressive' nuclear abnormalities may be observed, but seem to be secondary in the in vivo reaction. However, under certain conditions (combined treatment modalities) this nuclear effect may be of importance.


Acid base equilibrium in experimental acidosis of cows with and without rumen fistula. Acid base equilibrium in experimental acidosis of cows with and without rumen fistula. Acta Physiol. Pol., 1977, 28, (1): 77-84. Symptoms of acidosis caused by administration of saccharose into the rumen were more significant and lasted longer in the cows without rumen fistula than in those with it. At the peak of acidosis of pH of arterial blood was 7.29 and it was by 0.07 below that in the group of cows with fistula. The alkali reserve was lower by 6 mEq and the bicarbonate level by 5.2. Characteristic differences were observed in oxygen utilization and nitrogen metabolism. Thus, the results obtained in experiments on the cows with rumen fistula do not reflect the normal metabolic processes.


Photolysis of desmosine and isodesmosine by ultraviolet light. It is known that the pyridinium ring of a model compound such as N-methyl pyridinium chloride is cleaved by U.V. radiation at 254 nm. At acid pH the products obtained are methylamine and glutaconaldehyde. Under the same conditions desmosine and isodesmosine are degraded into lysine and probably into the homologous substituted ketone of glutaconaldehyde. At pH 6.0-7.0, a transient open-chain aminoaldehyde intermediate is observed which can either reform the original compound or be cleaved as at low pH. When intact elastin is photolysed for 20 minutes in water, approximately 75% of the (iso) desmosines are destroyed, accompanied by an increase of free lysine residues. No change in the concentration of the other amino acids, including tyrosine, are noted. It is therefore likely that the crosslinks engaged in peptide links are also cleaved photochemically.


The influence of histamine on metabolism of dopamine and serotonin in the rat striatum. The influence of histamine on metabolism of dopamine and serotonin in the rat striatum. Acta Physiol. Pol., 1977, 28 (2): 101--105. Histamine-2HC1 (Hi) given in a dose of 500 micron g did not change DA level in the striatum but HVA was increased by approx. 50%. The Hi-induced rise of HVA level was prevented in animals pretreated with an antihistaminic drug--mepyramine. The pretreatment of rats with atropine reduced significantly the Hi-induced rise of HVA concentration. Hi did not significantly influence 5-HT content in the striatum while the level of 5-HIAA was simultaneously increased by 15%. It is concluded that Hi-induced elevation of HVA content is not a direct effect of Hi on dopaminergic neurons but the Hi action is exerted indirectly through cholinergic system. The increase of serotoninergic activity is probably a consequence of an increased activity of dopaminergic neurons in the striatum.


Studies on lysyl oxidase of bovine ligamentum nuchae and bovine aorta. Lysyl oxidase had been purified to near homogeneity from bovine aorta and bovine ligamentum nuchae employing a modification of methods described by Harris et al., and Stassen and his colleagues. The aortic enzyme gives rise to at least three peaks and the ligament enzyme resolves into at least four peaks upon chromatography on DEAE cellulose. The molecular weight of each peak of both enzymes is approximately 30,000 daltons in sodium dodecyl sulfate. The aortic enzyme aggregates to species with molecular weights varying from approximately 60,000 to 1,000,000 daltons upon dialysis out of urea into phosphate-buffered saline. Temperature studies reveal that lysyl oxidase is stable to temperatures as high as 80 degrees C, although the assay optimum is 52 degrees C. Studies in progress suggest the temperature dependency of assay may reflect conformational changes in the elastin substrate.


The coacervate-sol transition observed with alpha-elastin and its N-formyl O-methyl derivative. The coacervate phase produced by raising the temperature of solutions of blocked alpha-elastin has water content and fibrillar structure at electron microscope level similar to fibrous elastin (Cox, B.A., Starcher, B.C., Urry, D.W. (1973) Biochim, Biophys. Acta 317, 209-213). The stability ranges of the coacervates under varying conditions of temperature, pH, salt concentration and concentration of added organic solvent have been investigated with results that suggest a marked sensitivity of elastin conformation to solution conditions.


Purification of vaccinia virus by zonal centrifugation and analysis of viral protein composition. Vaccinia virus propagated in rotated cultures of RK13 cells was purified by sucrose density gradient zonal centrifugation. The purified virus was dissociated with sodium dodecyl sulfate end its protein composition analyzed by polyacrylamide gel electrophoresis. The protein composition of the virion envelope, isolated by the non-ionic detergent Nonidet P-40, was also determined.


Effect of influenza virus on the immune responsiveness of animals. Infection of mice with A/Hong Kong/1/68 (H3N2) and A/PR8/34 (H0N1) influenza virus strains resulted in a significant inhibition of the formation of antibody-producing cells in response to administration of sheep erythrocytes and a reduced capacity of spleen cells to induce "graft-versus-host" reaction. The immunosuppression caused by influenza infection was observed for a long period of time post infection (3--6 months). The extent of inhibition of antibody production depended on the dose of virus, route of inoculation, the sequence of infection and immunization and the internal between them. Heat-inactivated virus exerted no immunosuppressive effect.


Effects of tilorone hydrochloride on experimental flavivirus infections in mice. The effect of tilorone hydrochloride on experimental infections of mice with West Nile, Langat and Dengue type 2 viruses were studied. The drug significantly reduced the mortality after intraperitoneal inoculation of West Nile virus, but failed to affect intracerebral infection with Langat or Dengue viruses. Tilorone partially reversed cyclophosphan-enhanced mortality after extraneural inoculation of West Nile and Langat viruses. The possible modes of action of tilorone, interferon-inducing ability and stimulation of humoral immunity, are discussed.


Experimental Hazara Virus infection in mice. Reproduction of Hazara virus in intracerebrally (ic) inoculated newborn white mice was studied by virological, serological and histological methods, electron microscopy and the direct fluorescent antibody technique. In the course of infection the virus was detectable in the blood, brain and some viscera, the largest amounts of virus occurring in the brain and liver. Pathomorphological lesions were localized in the brain and consisted of foci of neuronal destruction and marked oedema of the tissue. Electron microscopy of ultrathin sections of tissues from various parts of brains of infected newborn white mice killed at the height of infection revealed virus particles in perikaryon of the brain cortex neurons; accumulations of particles were found in vesicles of the Golgi complex and the endoplasmic reticulum.


Susceptibility of laboratory and domestic animals to experimental infection with Orungo virus. Laboratory and domestic animals: mice, hamsters, rabbits, sparrows, chickens and lambs were inoculated with Orungo virus to determine their susceptibility as evidenced by clinical response, viraemia and antibody development. Mice and hamsters circulated the virus and developed neutralising antibodies; clinical signs of disease included ruffled hair coat, hypersensitivity to sudden noise and hindleg paralysis. There was an age-related susceptibility to infection in these two animals. Rabbits and lambs developed neutralising antibody but not viraemia, nor did they show signs of illness. Sparrows and chickens neither circulated the virus, nor developed neutralising antibodies to Orungo virus.


The antiviral activity of dipyridamole.

The antiviral activity of dipyridamole. Dipyridamole, a coronary vasodilatator, was found to possess antiviral activity against representatives of different families. The antiviral properties were studied in chick embryo, human diplid and FL cell cultures by the agar diffusion plaque inhibition and plaque reduction tests and one-step growth cycle experiments. The inhibition of the virus-induced cytopathic effect was estimated quantitatively. Dipyridamole significantly inhibited the yield of members of the viral families Picornaviridae, Togaviridae, Orthomyxoviridae, Paramyxoviridae, Herpetoviridae and Poxviridae, as well as of Chlamydiaceae (sheep abortion agent).


Enzymatic activity of blood lymphocytes experimental tsutsugamushi fever in mice. The influence of tsutsugamushi fever infection on the metabolism of blood lymphocytes of mice differing in susceptibility to Rickettsia tsutsugamushi and of rifampicine and tetracycline treatment was studied. In susceptible mice, the activity of oxidation-reduction processes in lymphocytes increased at 7--10 days of the disease and became normal upon recovery of the animals. In mice with low susceptibility this increase of the activity began and terminated much earlier, at 3--5 days. Treatment of the infection with antibiotics resulted in a rapid arrest of the disease and normalization of the lymphocyte activity. The relationship between susceptibility of the animals to R. tsutsugamushi and the activity of oxidation-reduction enzymes is discussed on the example of succinate dehydrogenase.


Purification of free polyhedrosis virus infecting Galleria mellonella L. Free Galleria mellonella nuclear polyhedrosis virus was purified 4000--4500 times by Tween-80 treatment and repeated sucrose density gradient centrifugation, based on the ratio of infectivity to protein content as compared to the starting virus-containing suspension.


Biological characteristic of Nigerian strains of West Nile virus in mice and cell cultures. The biological characteristic in mice and cell cultures of 7 strains of West Nile (WN) virus isolated in Nigeria were studied. The pattern of virus development in most organs of mice infected with two of the seven strains tested was identical, while it varied with the remaining five strains. All 7 strains of WN virus multiplied with a cytopathic effect (CPE) in the four cell cultures examined.


Serotyping of coxsackieviruses by immune electron microscopy. Coxsackieviruses B1, B2 and B3 were identified by immune electron microscopy. The results were in good agreement with those of virus neutralization tests in cell cultures.


Plaque formation by alphavirus (Getah) in Culex Mosquito cells. Plaques were formed by Getah virus (an Alphavirus) which had been grown in BHK cells and passaged once in Culex cells before inoculation of Culex cell cultures. Plaques were not produced either by Getah or Japanese encephalitis (JE) viruses which had been passaged only in BHK cells. Plaque counts in Culex cell monolayers were almost the same as in BHK cells.


Role of normal cell antigens in the establishment of measles virus in newborn white mice. The Edmontson strain of measles virus was adapted to the brains of newborn white mice to which extracts from African green monkey kidney (Vero) cells used for maintenance of measles virus had been injected intracerebrally. The animals showed symptoms of involvement of the central nervous system (pareses, paralyses) which reappeared in subsequent passages.


Interaction of plasma membranes with influenza virus. VII. Effect on 3',5'-cyclic adenosine monophosphate phosphodiesterase activity. In chick embryo cells (CEC) and plasma membranes (PM) isolated therefrom, three forms of 3',5'-cyclic adenosine monophosphate (cAMP) phosphodiesterase (PDE) were demonstrated: (1) PDE activated only by Ca2+ (Ca-PDE); (2) PDE activated only by Mg2+ (Mg-PDE); and (3) PDE stimulated in the presence of 2 mM Mg2+ by low concentrations of Ca2+ (Ca-Mg-PDE). Purified influenza A virus, under suitable conditions, lowered the activities of these PDEs. The decrease was greater in samples incubated in the presence of adenosine triphosphate (ATP) than in those incubated in its absence.


Reduced renal acid excretion in malnutrition: a result of phosphate depletion. Eleven infants recovering from protein-calorie malnutrition secondary to acquired monosaccharide intolerance were found to have reduced plasma bicarbonate concentration associated with inadequate weight gain. Renal net acid excretion (NAE) was decreased to a mean of 34.2 micronEq/1.73m2/min. Titratable acidity (TA) was markedly reduced, accounting for only 16% of NAE. This marked reduction in TA was associated with reduced mean phosphate (PO4) excretion (.074 mg/min) and a reduced mean serum PO4 (3.9 mg/dl), suggesting PO4 depletion. Two patients received intravenous phosphate loads, resulting in an increase in mean NAE from 35.1 to 89.7 microgEq/1.73m2/min. A similar response was seen after oral PO4 supplementation. Three patients were studied after partial correction of their acidosis. At a relatively low plasma bicarbonate concentration (mean = 16.6 mmoles/liter) significant amounts of bicarbonate were detected in the urine (mean = 8.7 micronEq/1.73m2/min), suggesting a defect in bicarbonate reabsorption. Five patients studied after complete recovery from malnutrition had normal NAE in response to ammonium chloride load. The reduction in NAE appears to be secondary to unavailability of urinary buffers and a reduction in bicarbonate reabsorption; both of these defects can be explained by phosphate depletion.


Contribution of arterial blood lactate measurement to the care of critically ill patients. Arterial blood samples from 202 critically ill patients were studied. Lactate concentration, PO2, PCO2, pH, oxygen saturation, total CO2, and toe temperature were measured. Base excess, buffer base, actual bicarbonate, and standard bicarbonate were calculated. Analysis of the initial data obtained from each patient revealed that lactate concentration alone could not be used to predict survival. Elevations in lactate concentrations were observed in all types of acid-base disturbances. Survival was lowest (30%) for patients in metabolic acidosis with respiratory compensation, mean lactate concentration 10.5 mEq/l (mmol/l), and highest (65%) for patients in uncompensated respiratory alkalosis, mean lactate concentration, 2.57 mEq/l (mmol/l). Knowing the type of acid-base disturbance is necessary to evaluate the significance of elevated blood lactate values.


The pediatric practice of the child health associate. Child health associates are individuals who have completed the three-year Child Health Associate Program at the University of Colorado School of Medicine and are certified by the Colorado State Board of Medical Examiners to practice pediatrics under physician supervision. To our knowledge, this study is the first to describe the practice profile of child health associates. We found them able to provide health care services without direct physician assistance to 91.4% (2,160 of 2,363) of pediatric patients in ambulatory settings. They saw the same variety of patients as primary physicians and identified a broad range of common pediatric problems. Each supervising physician spent an average time of 5.9 minutes with the child health associate in evaluating the 8.6% of patients who required consultation. The child health associate is fully able to serve as a primary health care practitioner for children.


Immunologic studies and clinical follow-up HBsAg-positive polyarteritis nodosa. Three patients with hepatitis B surface antigen (HBsAg)-positive polyarteritis nodosa (PAN) who are clinically well 4 1/2-5 1/2 years after their initial illnesses are described. In each case electron microscopic studies demonstrated the presence of aggregates of HBsAg in both acute and quiescent phase sera. One patient had a lower circulating HBsAg titer during the acute illness, while no change in serial HBsAg titers was observed in the other two patients. Two of the three patients showed lymphocyte transformation to purified HBsAg during the quiescent phase of the PAN. The role of immune complexes in the pathogenesis of HBsAg-positive PAN is discussed.


Idiopathic proctitis. I. The morphology of proximal colonic mucosa and its clinical significance. A group of 31 patients with idiopathic proctitis were colonoscoped while they were symptomatic. Multiple mucosal biopsies were taken from the transverse, descending, and sigmoid colon and from the rectum. While visualization by colonoscopy revealed abnormalities limited to the most distal 18-20 cm of the colon, microscopic abnormalities were frequently seen in more proximal locations. Analysis of clinicopathological data indicates that there is good correlation between the extent of microscopic mucosal abnormalities and the clinical course. Patients with abnormalities limited to the rectum generally responded well to conventional treatment while patients with more proximal involvement were refractory to such therapy.


Low-dose methazolamide and intraocular pressure. Sixteen patients with increased intraocular pressure (over 20 mm Hg) received 25 and 50 mg of oral methazolamide, twice daily, during consecutive weeks and then 500 mg (Sequels) of acetazolamide. The two methazolamide regimens produced significant decreases in intraocular pressure. Acetazolamide treatment resulted in a greater decrease in intraocular pressure but more systemic acidosis and side effects.


Clinical implications of benzodiazepine pharmacokinetics. Pharmacokinetic research has shown that clear differences exist among benzodiazepines in rate and route of elimination and in the presence or absence of pharmacologically active metabolites. These findings and other results of pharmacokinetic research have clinical implications in terms of dosage schedules, drug accumulation during long-term therapy, antianxiety therapy in the elderly, drug interactions, pharmacotherapy in specific disease states, and the influence of route of administration on drug action.


The role of benzodiazepines in nonpsychiatric medical practice. The benzodiazepines are widely prescribed by many physicians for patients with depression, anxiety reaction, circulatory disorders, digestive disorders, tension headache, and pain in chest and back. According to various studies there is reason to believe that benzodiazepines not only possess the anxiolytic effects universally attributed to them but may also ameliorate somatic complaints affecting such systems as the cardiovascular and the gastrointestinal. twhether the bensodiazepines affect organ systems known to be linked in important pathophysiological ways to the nervous system deserves further study.


Brain mechanisms associated with therapeutic actions of benzodiazepines: focus on neurotransmitters. The sedative, muscle relaxant, antianxiety, and anticonvulsant effects of benzodiazepines may involve several distinct mechanisms because dissociation among these actions can be demonstrated with various drugs. Neurotransmitters displaying prominent interactions with benzodiazepines include gamma-aminobutyric acid (GABA), glycine, norepinephrine, and serotonin.


Benzodiazepines: behavioral and neurochemical mechanisms. The therapeutic effects of benzodiazepines in psychoneurosis may depend in part on their ability to release or disinhibit a patient's anxiety-suppressed gratification-seeking behavior. Benzodiazepines may disinhibit behavior by reducing the activity of serotonin (and possibly acetylcholine) neurons in the brain's "punishment" system. Reduction of serotonin transmission may be due to a facilitation of gamma-aminobutyric acid (GABA)-mediated presynaptic inhibition at the serotonin nerve terminal.


Neural mechanisms of benzodiazepine actions. Current experimental paradigms emphasize neurotransmitter-specific interactions to explain the behavioral effects of benzodiazepines. According to this approach the broad range of effects observed suggests the involvement of several transmitter systems without rigorously establishing that any single transmitter system or physiological synaptic function is either necessary or sufficient to express all benzodiazepine actions. Among the effects that occur, potentiation of amino acid-mediated presynaptic inhibition in the spinal cord and postsynaptic inhibitions elsewhere in the brain are attractive testable hypotheses. However, direct physiological evidence that benzodiazepines stimulate gamma-aminobutyric acid (GABA) or other amino acids specifically and exclusively is needed to corroborate this view.


Paradoxical response to dopamine agonists in tardive dyskinesia. The authors conducted an extensive pharmacological analysis of a patient severely affected by tardive dyskinesia. No drug treatment gave lasting clinical improvement. Several agents recently recommended for this condition, dimethyl aminoethanol, clozapine, and thioridazine, failed to modify the dyskinesia. Reserpine caused a worsening of the symptoms. A paradoxical and unexpected improvement was observed with apomorphine injections and with low-dosage oral L-dopa. These two drugs may have acted by stimulating presynaptic inhibitory dopamine receptors.


Host feeding patterns of Connecticut mosquitoes (Diptera: Culicidae). Blood-engorged Coquillettidia perturbans, Psorophora ferox, Culex, Culiseta, and Aedes mosquitoes were collected principally by sweep net from salt marsh and woodland habitats in Connecticut. Of the 570 mosquitoes tested, precipitin tests identified the origins of 517 blood meals and revealed distinct host feeding patterns. Aedes mosquitoes fed chiefly on mammals; A. abserratus, A. cantator, and A. vexans showed selectivity for cattle and (or) horses. A. cantator also obtained blood from avian hosts and, in some instances, showed mixed passerine-mammal blood meals. These findings increase the vector potential of this salt marsh mosquito for eastern equine encephalomyelitis virus. Feedings on deer by A. abserratus suggest potential involvement of this mosquito in the transmission of certain subtypes of California encephalitis. Culex-pipiens, C. restuans, Culiseta melanura, and Cs. morsitans dyari acquired blood almost exclusively from passeriform birds.


Malignant hypertension as a cause of massive intestinal bleeding. A forty-one year old man with a three year history of malignant hypertension developed massive rectal bleeding. A mesenteric arteriogram showed vascular changes compatible with necrotizing angitis. Histologic examination of the resected right hemicolon confirmed malignant hypertension as the cause of angitis.


[Gerontology in rural and mountains regions aged people in the country and in mountain regions (author's transl)]. The gerontologic problems of people living in the country and in mountain regions always were neglected in comparison to those of townsmen. In the last decade an important structural change has happened, caused on the one side by the fact that more and more people leave the country for the towns, and by the problem of overaged persons in the country; on the other side this change is a consequence of improvement by modern technical acquisitions (more agricultural machines, silos), living hygiene and the tourism. The living conditions in the past and today in Switzerland are shown, referring to various publications. The ecological change also hits the aged people, financially by revenues, completion of private help organizations, rebuilding of homes for the aged persons in every village and regional nursing home, as well as household helps for those elderly people who still live in the country in their own houses. The qualitative differences between living conditions in the country and in town will in the near future be equalized--which is especially mentionned.


[Problems of aged people in rural regions of the Swiss Canton St. Gall (author's transl)]. Based on the structure of the mountain population, the living conditions of the aged (in rural communities 11-17% are older than 65) are shown. By public planning and cooperation of private organizations a material security of the aged has been strived after and mostly reached in the last 15 years--with the tendency to leave the aged in his own house or at least in the environment of his native village. Homes for the aged were built--if possible in every community--on the basis of 50 beds in a home for the aged and 35 beds in a nursing home for 10.000 inhabitants (83% in nursing homes an 17% in acute hospitals with geriatric departments). The individual help for the aged: activation by offering common institutions, ingenious activity, non-public advice offices, household help is deduced and the planning for the coming decade mentionned.


[Living conditions of the rural population in France. Situation in 1974 and evolution from 1967 to 1974 (author's transl)]. A survey of the living conditions of aged people in rural regions of France in 1974 and a comparison with the previous surveys of 1967/68 in 302 rural vallages are analysed. Of the 4,800 persons in 1967/68, by 1974 1,609 were dead (35%). After questioning the 2,191 living persons (1,275 farmers and 916 non farmers) an increased number of widowed people appeared in those 7 years. For men in 1967/68: 20%, now 28%; for women in 1967/68: 61%, now 72%. In the age group 75-79 three times more women lost their husbands than men lost their wives. 2/3 of the households remained identical, 1/5 became smaller, 1/8 increased. The comparison (excluding the dead persons) showed no significant differences in the health conditions. Detailed questions were asked regarding social relationships but it is very difficult to analyse the date due to the great number of dead persons. The difference between farmers (whose number decreases) and non farmers (whose number increases) is especially mentioned and specific problems are treated separately. In France ageing in rural areas is increasing rapidly: in 1968, 393 rural counties contained 20% of people aged 65 or more.


[Aging in cities and in the country (author's transl)]. A growing concern with ecological issues has led gerontologist to analyze the life-situation of aged people in cities and in the country more precisely. While it is generally assumed that aging in the country has advantages to aging in the city, statistical figures (e.g. income, living conditions, health status, educational opportunities, institutions for the aged) show that country dweller's "cumulative disadvantages" have to be taken into consideration, disadvantages caused by interacting societal and individual factors in rural life. Psychological investigations--as e.g. the Bonn Longitudinal Study of Aging (BLSA)--show positive correlations between a central location of the home and increased general activity, broader scope of interests, more frequent use of communication media (newspapers, newscasts), better mood, greater readiness for involvement. While city-dwellers are more frequently engaged in social contacts outside of the family, country dwellers are more involved in interactions with the immediate family. The following practical considerations for the improvement of the situation of the aged in the country are presented: beginning in childhood and youth, conditions should be granted which allow the individual to live in ways which prevent too early aging; this ought to be supplemented by providing activating and stimulating environments for aging people and help for the aged, be it in special institutions or through activities in their familiar environment. It is shown that a differential ecogerontology is required, since (1) a simple distinction between city and country is by far too global, (2) similar ecological conditions are known to have different effects, depending on inter-individual differences, and (3) intraindividual patterns, and (4) it becomes evident that objective ecological conditions do not as clearly determine behavior in age as do cognitive representations of these ecological variables. This last statement is in accordance with the cognitive theory of aging. There can be no doubt that ecological variables influence the process of aging, but there is nothing like the aging in the country.


[The old aged in a mountain community (author's transl)]. In a mountain community of Eastern Switzerland at 1000 m with about 1000 people more than 17% are older than 65. 2/3 of the aged live in their own household, 1/4 lives together with the young generation. Only 8% spend their late years in a home for the aged, which lodges also easy nursing cases. Cheaper flats, cooperation in the farm (also in the home for the aged), economical style of living allow an adequate, satisfactory life in the well-known rural society.


[Medical problems of the aged in a mountain community of the Swiss Canton Appenzell A.Rh. (author's transl)]. The report about a mountain community (Urnäsch) with 2400 inhabitants at 700-1100 m above sea level with 16-18% aged over 65 shows the help for the aged by several groups: women's club, church, cultural institutions. The community doctor looks after 4 homes for the aged. He also treats those patients living in their own houses. The aged usually prefere being nursed and dying at home in the shelter of the native mountain area.


[The aged in a mountain region of the swiss grisons and their problems (author's transl)]. The way of life of the elderly people in a Swiss mountain valley (Schanfigg, Grisons) is statistically examined and illustrated by detailed descriptions. The author as general practitioner for the region (9 villages with a total of 1.500 persons, 20% over 65 years old) knows everybody personally. The majority of old people (75%) do no longer live together with the younger generation but are living in their own houses, either single or in "symbiotic" couples (married, relatives, other combinations). There is no shortage of living-quarters, partly due to the trend of depopulation. Besides the official national pension (AHV) there is no need for further financial administrative support; the everyday-supply is organizied by extensive house-delivery-services; practical assistance comes from the side of the neighbours or is realized within the symbiotic household. Medical services are available in any place and at any time; social activities could still be improved. According to their tradition and mentality the elderly people are living socially integrated in the community of the valley.


Endogenous opiates-a progress report.

Endogenous opiates-a progress report. The "opiate receptor" has become a  well-accepted entity, stimulating the search for an endogenous agonist. This has successfully revealed several different endogenous peptide opiates whose physiological role is under intense investigation, contributing to our understanding of pain and of opiate tolerance and dependence. A review of the current literature is presented.


Effect of sodium bicarbonate on canine left ventricular function. Left ventricular performance was evaluated in seven canine right heart bypass preparations during and after the intraauricular administration of sodium bicarbonate (100 ml, 1100 Osm, 60 mEq). Under conditions of constant cardiac input and left ventricular volume, sodium bicarbonate produced mild and brief left ventricular depression, as manifested by a decline of left ventricular dp/dt with simultaneous rise of left ventricular end-diastrolic and left atrial pressures. These findings occurred as aortic impedance fell. Identical results accrued in paced and unpaced preparations. The data lends credence to the proposition that a sudden rise in blood pCO2 produces increased transport of CO2 across the cardiac membranes with intracellular acidosis. However, the data is also compatible with hyperosmolality induced contractile depression. Possible clinical implications are discussed.


Secretin-stimulated serum gastrin levels in hyperparathyroid patients from families with multiple endocrine adenomatosis type I. Twenty-three patients with hyperparathyroidism from six families with the multiple endocrine adenomatosis (MEA) I-syndrome were tested by secretin provocation. In nine cases this led to increases in serum gastrin ranging from 298 to 13 300 pg/ml, whereas the maximum rise in gastrin in the other 14 patients was 32 pg/ml. In all nine patients with marked gastrin responses to secretin, the Zollinger-Ellison syndrome was diagnosed by gastric acid hypersecretion and large increases in gastrin after calcium administration. Six of these nine patients had, at most, minor postprandial rises in gastin and two had demonstrable tumors. In 34 normal subjects, 23 nonaffected members of families with MEA I-syndrome, and 42 patients with various diseases the maximum gastrin response to secretin was 21 pg/ml. We conclude that secretin provocation is helpful in the diagnosis of the Zollinger-Ellison syndrome, especially when basal serum gastrin levels are only slightly elevated.


[Cecal motility in the rabbit. III. Duality of fecal excretion]. The production of soft pellets (caecotrophs) was studied in conjunction with feeding behaviour, biochemical changes in caecal contents, motility of the caeco-colic region and transit of digesta in the colon in rabbits fed ad lib. or receiving one or two daily meals. Studies were carried out on animals either collared or free in their cages. Ingestion of soft pellets was recorded from electrodes fixed in the esophageal wall. Similar electrodes positioned on the caecum, proximal and distal colon and the fusus coli monitored regional electrical activity. Transit time for the colon was determined using a marker substance PSP. In animals fed ad lib. soft pellets were usually produced in the morning and this occurred 5 to 6 hours after the daily meal in the same animals. In subjects fasted for 15 hours, a daily meal was followed by increase in the volatile fatty acid concentration and decrease in the pH of caecal contents. Irrespective of the regimen the production of soft pellets coincided with a decrease in motility of both caecum and proximal colon and an increase in that of the distal colon. The transit time for the colon was 1.5 to 2.5 times faster for the production of soft than for the production of hard pellets.


Experiments for the production of graft-versus-host reaction in adult and infantile mice by means of human immunocompetent cells. By administering anti-mouse ATS five times to random-bred Swiss albino mice weighing 16-18 and 10-11 g respectively, the authors have tried to produce immunological depression of such a degree which would allow living human leukocytes to cause GVH reaction. On the basis of the results it may be stated that with the serum dosage and manner of treatment applied, the human graft was not able to act against the recipient organism and to produce differences in body weight.


Exeriments for the production of graft-versus-host reaction in newborn mice by means of human immunocompetent cells. It was not possible to produce the wasting disease in newborn mice by administering human leukocytes in Hanks' solution, or suspended in m-ATS or h-ATS. The attempt of the authors to produce immunosuppression by the administration of m-ATS started at newborn age-as a result of which the human immunocompetent cells would have produced serious GVH reaction-resulted only in a trend of GVH. The authors used only body weight measuring for detecting the GVH reaction. More sensitive parameters will be employed in their experiments in progress.


Study on the interaction of lymphotropic cytostatic agent treatment and graft-versus-host (GVH) reaction in mice. F1 hybrid mice (C57BL X C3H) suffering from graft-versus-host disease, were treated with dianhydrodulcit (DAD) a lymphotrop cytostatic agent. 15 mg/kg of the compound was injected intraperitoneally, 8 days following the administration of the parental spleen cell suspension. The interaction between the two interventions is discussed on the basis of the rate and time course of deaths observed is the individual groups, as well as on the state of the lymphoid organs of the succumbed and sacrificed animals.


Oxidation of stibnite by Thiobacillus ferrooxidans. Optimum pH, temperature and pulp density for microbiological leaching of museum-grade stibnite mineral has been investigated using a stibnite-adapted strain of Thiobacillus ferrooxidans. Optimum conditions were found to be pH  1.75, 35 C and 12g solid substrate per 100 ml of basal salts medium as the initial dose. The energy of activation was determined to be 16.8 kcal per mole, and the temperature coefficient 2.2. The highest total dissolved antimony concentration, [Sbt] = [Sb+3] + [sb+5] + I1SbO2+], was about 1400 mg/litre, due to relatively low solubility of (SbO)2SO4 and (SbO2)2SO4.


Fungal growth on C1 compounds: quantitative aspects of growth of a methanol-utilizing strain of Trichoderma lignorum in batch culture. A study was made of some salient parameters that influence growth of the methanol-utilizing fungus Trichoderma lignorum growing in batch culture on a minimal medium containing methanol as the sole source of carbon. Maximum cell yield was recorded at the expense of 1.58 g of methanol per liter. Inhibition was observed with methanol concentrations in excess of 4.7 g/liter. The optimum temperature for fungal growth was 23 degrees C. Growth of the fungus was directly proportional to an inorganic nitrogen concentration up to 0.2 g of NH4NO3 per liter. No inhibition of growth occurred at any concentration of NH4NO3 up to 11 g/liter. The pH of the growth medium decreased from 7.0 to 3.5 during growth of the fungus on methanol, which may have been due, in part, to the accumulation of trace amounts of organic acids in the growth medium. An analysis of the commercial potential of the fungus, as a source of edible protein, indicated that the strain of methanol-utilizing T. lignorum used was uneconomical in terms of the yield and the specific growth rate.


Iodination of staphylococcal enterotoxin B by use of chloramine-T. This report describes the conditions that are necessary for iodination of staphylococcal enterotoxin B (SEB) by use of chloramine-T. Makor Chemical Co. SEB and the two major SEB components, which were prepared by isoelectric focusing of partially purified SEB, were used in these studies. The antigenic activity of the SEB preparations was monitored by radioimmunoassay as the oxidation/reduction (O/R) potential was increased by addition of chloramine-T. The SEB preparations lost antigenic activity rapidly at pH 7.5 and room temperature when sufficient chloramine-T was added to raise the O/R potential above 250 mV. Iodinated SEB with satisfactory immunoreactivity was prepared by omitting carrier iodide from the iodination reaction mixture and by using at least 1 mg of SEB/ml, steps which made the O/R potential more stable, and by stopping the reaction before the O/R potential exceeded 250 mV. Comparison of the chloramine-T method with a lactoperoxidase/H2O2 method of iodinating SEB showed the latter to cause a greater loss of immunoreactivity.


Identification of the virucidal agent in wastewater sludge. Anaerobically digested sludge contains an agent that causes irreversible inactivation of poliovirus. It has now been shown that the agent responsible for this activity is ammonia. The effect of ammonia on poliovirus appears to be typical for picornaviruses, but reovirus, an enteric virus of another group, is quite resistant to this compound. Because ammonia is not virucidal in its charged state, it expresses significant activity only at pH values greater than 8. Therefore, increasing the pH of sludge should cause rapid inactivation of indigenous picornaviruses.


Graft-vs-host reaction.

Graft-vs-host reaction. Observations surrounding the clinical manifestations and pathological studies of a neonate who died at 9 weeks of age, indicate that distinctive cutaneous, histopathologic, and ultrastructural findings occur when graft-vs-host reaction (GVHR) complicates combined immune deficiency syndrome (CIDS). The prominence and specificity of the epidermal lesions, particularly a necrotic cell that occurs in association with satellite lymphocytes ("satellite cell necrosis" (SCN)), lead us to recommend that a cutaneous biopsy be performed to facilitate an early definitive diagnosis. Dermatologists can recognize GVHR at the bedside and establish the diagnosis with the pathological findings obtained from the skin biopsy.


Haemagglutination tests in the study of Ascaris epidemiology. Haemagglutination tests using adult Ascaris suum antigen were performed on sera from 810 people from three areas in Papua New Guinea and East Timor. In the area with the highest childhood Ascaris infection rates and egg-counts (Kaul), titres were highest and remained high throughout life. There was a significant negative correlation between titre and eosinophil count, and it is suggested that high titres in adult life result from continuous usually unsuccessful reinfection, and that the declining egg-counts and infection rates with increasing age may be the result of an immune mechanism, and not decreased exposure. In the two other populations the less intense Ascaris infection was reflected in the lower titres, with no correlation between titres, infection or eosinophilia. Although the haemagglutination test as used here is unsuitable as a diagnostic aid, it is valuable in studying the epidemiology of Ascaris infections.


Effects of various neuroleptics on rabbit hyperthermia induced by N, N-Dimethyltryptamine (DMT) and d-amphetamine. The effects of various neuroleptics were studied on N, N-dimethyltryptamine (DMT, 3.2 mg/kg) and d-amphetamine (3.2 mg/kg) induced hyperthermia in the rabbit. Complete dose-effect curves were obtained. The order of potency for antagonism of DMT-induced hyperthermia was: methiothepin greater than octoclothepin greater than or equal to oxyprothepin greater than perathiepin greater than dokloxythepin greater than mianserine greater than loxapine greater than oxypertine greater than chlorpromazine greater than pipamperone greater than fluphenazine greater than thiothixene greater than haloperidol greater than molindone. The order of potency for antagonism of d-amphetamine hyperthermia was: haloperidol greater than chlorpromazine greater than oxypertine greater than octoclothepin and methiothepin. For these five drugs, the order of potency for antagonism of amphetamine hyperthermia was the reverse of the order for antagonism of DMT hyperthermia. Methiothepin reduced d-amphetamine-induced hyperthermia effectively at a very high dose (0.32 mg/kg) and variably at lower doses. The results indicate that neuroleptics differ markedly in their specificity of antagonism of DMT and d-amphetamine which may act through different neurotransmitter mechanisms (tryptaminergic vs. adrenergic).


Inhibition of dopamine synthesis in chronic schizophrenia. Clinical ineffectiveness of metyrosine. According to the dopamine (DA) hypothesis of schizophrenia, there is a functional excess of dopaminergic activity within unspecified areas of the brain in schizophrenic patients. As a clinical test of this hypothesis, we administered metyrosine for three weeks to symptomatic chronic male schizophrenic patients who were maintained on suboptimal doses of neuroleptic agents. Metyrosine inhibits tyrosine hydroxylase, the rate-limiting enzymatic step in the synthesis of DA. No clinical improvement was observed, using the National Institute of Mental Health Inpatient Behavioral Rating Scale or the Brief Psychiatric Rating Scale. Central inhibition of DA synthesis by metyrosine was suggested, however, by (1) the development of extrapyramidal side effects and (2) a significant increase in plasma prolactin concentrations. Plasma chlorpromazine concentrations remained unchanged during metyrosine treatment. There was, nevertheless, a significant improvement on the scores of the Wechsler Adult Intelligence Scale Comprehension subtest, which measures judgment and common sense. This finding suggests that DA may be involved in the regulation of subtle psychological processes. The results are discussed in light of the DA hypothesis of schizophrenia and previous reports suggesting that metyrosine potentiates the antipsychotic effect of neuroleptics in schizophrenia.


Blood serum peptidases in patients with ovarian carcinoma treated with Ledakrin. The authors observed changes in activity of leucine amino-peptidase (E.C. 3.4.1.1--LAP), gamma-glutamyl transpeptidase (F.C 2.3.2.2--GGTP) and Co++-activated acylase in blood serum of patients with ovarian carcinoma, with or without ascites, treated with Ledakrin (1-nitro-9-[3-dimethylaminopropylamino] acridine). It was stated that the activities of LAP and GGTP increased during the treatment and during tumor progression. The level of Co++-activated acylase increased only slightly during the treatment and therefore, the determination of this enzyme appeared to be of no use in monitoring the therapy of ovarian carcinoma.


[Ways of correcting certain metabolic processes in the myocardium in myocardial insufficiency]. The article deals with the following trends along which according to the author, investigations aimed at search for ways of correcting disturbed metabolic processes in the cardiac muscle in its incompetence should develop: 1) restoration of properties of contractile proteins and creation of a basis for successful formation of the processes of compensatory hyperfunction and hypertrophy of the myocardium; 2) correction of the electrolytic balance with regulation of the skin mechanisms of the process of contraction of myofibrils; 3) restoration of the energy potential of cells; 4) withdrawal of the damaging effect upon the myocardium of some products of its disturbed metabolism.


[Use of formaldehyde with pH 8 0 as a fixative for electron and fluorescence microscopy]. For fixation of the material to be investigated at the light and ultrastuctural level the author suggests to use 4% formaldehyde obtained by depolymerization of paraform on 0.1 M phosphate buffer with end pH 8.0 of the solution. This fixative stabilizes well glycogen and tissue structure. The ultrastructural characteristics of cells following continuous (up to 130 days) fixation are comparable with those obtained after fixation with aldehydes by conventional techniques. Results of histological PAS test, Feulgen's reactions and those to acid polycaccharides were identical to the results obtained in fixation with neutralized formalin. The possibility of prolonged storage of tissues makes it possible to perform delayed and repeated ultrastructural investigations of clinical and experimental material.


Hydrogen ion concentration of human tears: Effects of prolonged eye closure. Using a closed chamber microelectrode technique, human tear hydrogen ion concentration was measured following periods of eye closure of 6 to 8 hours and then compared with normal open eye findings from the same patients. Closed eye tears were found to be significantly more acid (average age difference = 26 nM/1) and required some 3 to 4 hours to return to average open eye levels. The population rate for this return averaged 6.9 nM/1/hr. This degree of acid shift measured for prolonged eye closure, however, remained, for the average patient, well within comfort limits commonly cited, and appeared insufficient to distrub the water content or optical parameters of hydrophilic polymers in common use today for therapeutic or cosmetic purposes.


Surgery for unstable angina.

Surgery for unstable angina. A series of 84 patients with unstable angina, treated surgically by grafting procedures between October 1970 and September 1976, have been reviewed. The study indicates that extensive coronary artery disease is common in these patients, and suggests that operation may favourably influence mortality, both immediate and delayed, but does not reduce the risk of myocardial infarction. Eighty per cent of the patients were relieved of angina and able to lead a reasonably normal existence.


Rapid inpatient treatment of severe female sexual dysfunction. A mult-faceted inpatient programme for overcoming severe female sexual of dysfunction using behavior modification techniques is described. The results obtained in a pilot study on 17 consecutive patients are presenre present.


Properties of glutathione release observed during reduction of organic hydroperoxide, demethylation of aminopyrine and oxidation of some substances in perfused rat liver, and their implications for the physiological function of catalase. The enhanced reduction of t-butyl hydroperoxide by glutathione peroxidase is accompanied by a decrease in the cellular concentration of both glutathione and NADPH in isolated liver cells, resulting in the release of GSSG (oxidized glutathione) from the perfused rat liver. This phenomenon, first reported by H. Sies, C. Gerstenecker, H. Menzel & L. Flohé (1972) (FEBS Lett. 27, 171-175), can be observed under a variety of conditions, not only with the acceleration of the glutathione peroxidase reaction by organic peroxides, but also during the oxidation of glycollate and benzylamine, during demethylation of aminopyrine in the liver of the phenobarbital-pretreated rat and during oxidation of uric acid in the liver of the starved rat pretreated with 3-amino-1,2,4-triazole. The rate of release of GSSG is altered markedly by changes in the metabolic conditions which affect the rate of hepatic NADPH generation. Thus, regardless of whether achieved by enhanced oxidation of glutathione by glutathione peroxidase or by oxidation of NADPH through other metabolic pathways, an increase in the cellular concentration of GSSG appears to facilitate its release. It has been found that, in addition to the hexose monophosphate shunt, the mitochondrial NADH-NADP+ transhydrogenase reaction plays an important role in supplying reducing equivalents to the glutathione peroxidase reaction and in maintaining the cellular oxidation-reduction state of the nicotinamide nucleotides. Spectrophotometric analysis of the steady-state concentration of the catalase-H2O2 intermediate with simultaneous measurement of the rate of release of GSSG leads to the conclusion that intracellular compartmentation of catalase in the peroxisomes and glutathione peroxidase in the cytosol and mitochondria distinguishes the reactivities of these enzymes one from the other, and facilitates their effective cooperation in hydroperoxide metabolism in the liver.


A kinetic study of the soluble 5'-nucleotidase of rat liver. 1. The kinetic properties of the 5'-nucleotidase (EC 3.1.3.5) present in the cytosol of rat liver were investigated in relation to the conversion of adenine nucleotides into uric acid, with particular reference to the stimulation of this process by fructose. The enzyme was assayed by the release of Pi and by a new and more sensitive radiochemical procedure. 2. When IMP was used as substrate, the partially purified enzyme displayed almost hyperbolic kinetics (h = 1.1) with S0.5 = 1.2 mM. Similar kinetics were observed with GMP and other nucleoside 5'-monophosphates, except AMP. 3. Vmax. of the enzyme for AMP was about the same as for IMP, but the kinetics were sigmoidal (h = 1.6) with S 0.5 = 10 mM. 4. The hydrolysis of IMP was inhibited competitively by GMP. IMP, at concentrations up to 0.5 mM, had a paradoxical stimulatory action on the hydrolysis of 2-5 mM-AMP and was inhibitory at higher concentrations. 5. The activity of the enzyme towards AMP and IMP was stimulated by ATP and GTP, and inhibited by Pi. Activators and inhibitor approximately cancelled each others' effects. At pH 7.4, the enzymic activity with 0.2 mM-AMP was undetectable under physiological conditions. 6. It is concluded that, in the liver cell, AMP is not hydrolysed by the soluble 5'-nucleotidase, but that its degradation requires prior deamination to IMP.


Changes in mammary-gland acetyl-coenzyme A carboxylase associated with lactogenic differentiation. The process leading to the rise of acetyl-CoA carboxylase activity in rat mammary tissue after the onset of lactation was investigated. The kinetics of change in enzyme activity and enzyme immunotitratable with antibody against avian liver acetyl-CoA carboxylase were determined during the course of lactogenic differentiation. The antibody inactivates and specifically precipitates acetyl-CoA carboxylase from rat mammary tissue as well as that from chicken liver cytosol. Characterization of the immunoprecipitate of the mammary tissue carboxylase by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis reveals a single biotin-containing polypeptide of about 230000mol.wt. This molecular weight is approximately twice that reported for the avian liver enzyme. However, chicken liver cytosol prepared in the presence of trypsin inhibitor and subjected to immunoprecipitation gives rise to a biotin-containing subunit of 230000mol.wt. as determined by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis; omission of proteinase inhibitor leads to a subunit(s) approximately one-half this size. Throughout gestation both carboxylase activity and amounts of immunotitratable enzyme remained low; however, after parturition both parameters rose concomitantly to values 30-40 times the initial values. Therefore the elevated concentration of acetyl-CoA carboxylase appears to result from an increased rate of synthesis of enzyme relative to degradation rather than to activation of a pre-existing form of the enzyme.


Possible multiple binding sites for o-aminophenol on uridine diphosphate glucuronyltransferase. 1. Hepatic microsomal UDP-glucuronyltransferase (EC 2.4.1.17) derived from either weanling or adult rats exhibits three pH optima, at pH 5.4, 7.2 and 9.2, when o-aminophenol is the acceptor substrate, whereas p-nitrophenol is the acceptor substrate only on pH optimum is observed, at pH 5.4.2. Prior treatment of rats of either age with 3-methylcholanthrene results in a 2-3-fold increase in o-aminophenol conjugation at pH 5.4 and a 6-9-fold increase at pH 9.2. At pH 7.2, the induced enzyme is 2 to 3 times more active towards o-aminophenol than the control enzyme, but no pH optimum is demonstrable. 3. o-Aminophenol conjugation at pH 5.4 and 9.2 is inhibited competitively by both p-nitrophenol and p-nitrophenyl glucuronide, suggesting that the two phenolic aglycones share the same binding site. At pH 7.2, however, p-nitrophenyl glucuronide does not inhibit o-aminophenol conjugation, suggesting that the binding site at this pH is not shared by the two phenols. These data are consistent with the existence of more than one binding site for o-aminophenol on UDP-glucuronyltransferase.


Purification of two hexosaminidases from human kidney. Hexosaminidase forms A and B were isolated from human kidney in a homogeneous state as demonstrated by electrophoretic and enzymic criteria. The enzymes were stable for at least 18 months when stored at -20 degrees C in 0.025 M-phosphate buffer, pH 6.5. The molecular weights of forms A and B were estimated by gel filtration to be 111 000 +/- 1500 and 114 000 +/- 1600 respectively. The molecular weights of hexosamidase A and B subunits were determined by using polyacrylamide-gel electrophoresis in the presence of sodium dodecyl sulphate. Hexosaminidase A dissociated into one subunit with mol.wt. 68 000. Hexosaminidase B dissociated into three subunits with mol. wts. 100 000, 68 000 and 37000 respectively, and one protein band of mol.wt. 140 000. After treatment of hexosaminidases A and B with iodoacetic acid, the molecular weights of the carboxymethylated polypeptide subunits were also estimated. Carboxymethylated hexosaminidase A dissociated into one major subunit of mol.wt. 18 000 and two other protein bands of mol.wts. 65 000 and 100 000. Carboxymethylated hexosaminidase B dissociated into one major subunit for mol.wt. 19 000 and an additional band of mol.wt. 37 000. The Km of the enzymes for the synthetic substrate p-nitrophenyl 2-acetamido-2-deoxy-beta-D-glucopyranoside was 0.8 mM. Both enzymes were inhibited or activated by various metal ions. Double pH optima for the enzymes were found at pH 4.5 and 4.8.


The kinetics of the recombination reaction between apomyoglobin and alkaline haematin. Apomyoglobin was prepared by an extremely mild modification of the acid/butanone technique, and the kinetics of the recombination reaction between this preparation and alkaline haematin were studied. The recombination has been shown to be precisely second-order and mono-phasic. Rate constants obtained from the study are in good agreement with values obtained previously by an indirect technique not involving separation of haem and apoprotein.


Assay of flavin nucleotides in pancreatic islets by a differential fluorimetric technique. Differences in fluorescence intensity between FMN and FAD at high and low pH values were utilized to determine the concentration of each nucleotide. Amounts down to 1 pmol were measurable. The FMN and FAD contents of pancreatic islets of obese-hyperglycaemic mice (gene symbol ob/ob) were compared with those of the exocrine pancreas, the liver and heart muscle. As expected, the FAD content of each tissue was greater than that of FMN. The contents of both nucleotides were significantly higher in the islets than in the exocrine part of the pancreas, but lower than in the heart muscle and liver. Possible relationships between the flavin content of the islets and their capacity for oxidative phosphorylation are briefly discussed.


The highly electrophilic character of 4-chloro-7-nitrobenzofurazan and possible consequences for its application as a protein-labelling reagent. 4-Chloro-7-nitrobenzofurazan possesses at least one highly electrophilic centre (C-6) that is much more reactive towards nucleophiles than position C-4, the irreversible alkylating site of this reagent. Possible consequences of the electrophilic character of 4-chloro-7-nitrobenzofurazan for its application as a protein-labelling reagent are discussed.


Acid dissociation constants of glycopeptides. Glycopeptides containing mainly four amino acid residues in the sequence Asn-Leu-Thr-Ser, with small amounts of additional amino acid residues, were isolated from enzymic hydrolysates of hen's-egg albumin. Heterogeneity of the carbohydrate moiety was confirmed. Acid-base titrations showed that the alpha-amino group has a pKa value of 6.43 at 25 degrees C. The standard free engery and entropy changes associated with the ionization at 25 degrees C were 37.2kJ-mol-1 and -0.014kJ-mol-1- K-1 respectively. The complications arising in the interpretation of titration curves of the glycopeptides, which are heterogeneous with respect to the peptide chain, were considered and discussed in the light of the earlier suggestion that the titration curve of the glycopeptide might be interpreted as being due in part to a structure in which the hydroxyl group of the threonine residue is hydrogen-bonded to the beta-aspartamido oxygen atom [Neuberger & Marshall (1968) in Symposium on Foods - Carbohydrates and their Roles (Schultz, H.W., Cain, R.F. & Wrolstad, R.W., eds.), pp. 115-132, Avi Publishing Co., Westport, CT]. It is concluded that either the glycopeptides do not contain a hydrogen bond of that type, or, if they do, that it cannot be recognized by acid-base-titration studies.


The apparent absence of involvement of biotin in the vitamin K-dependent carboxylation of glutamic acid residues of proteins. The mechanism of the vitamin K-dependent post-translational carboxylation of the gamma-carbon atom of glutamic acid residues in proteins remains obscure. Experiments were performed in vivo and in vitro in an attempt to establish a role for biotin in the transfer of the carboxyl group. Weanling male rats were fed on a biotin-deficient diet until severe biotin deficiency was induced. Their degree of biotin deficiency was documented by assaying for liver acetyl-CoA carboxylase activity, which was about 15% of normal. However, one-stage and two-stage prothrombin times measured on the plasmas were normal. In addition, the liver microsomal fraction did not contain any more prothrombin precursor than did that of normal rat liver. Experiments were done in vitro in which vitamin K-dependent fixing of 14CO2 was measured in the liver microsomal fraction from vitamin K-deficient male rats in the presence or absence of avidin. No evidence for an avidin-sensitive critical biotin-containing site was obtained. Thus neither series of experiments suggests a role for biotin; the data are compatible with carboxyl transfer occurring either through a carboxylated vitamin K intermediate; or via a yet to be identified intermediate, or perhaps via CO2 itself.


The binding of calcium to a salivary phosphoprotein, protein C, and comparison with calcium binding to protein A, a related salivary phosphoprotein. The binding of Ca2+ to a salivary phosphoprotein, protein C, was studied by equilibrium dialysis. In 5mM-Tris/HCl buffer, pH 7.5, protein C bound 190 nmol of Ca2+/mg of protein. The apparent dissociation constant, K, was determined to be 1.9 x 10(-4)M and the binding of Ca2+ to the protein was non-co-operative. The binding of Ca2+ to protein C apparently depends on groups which ionize above pH 5.0. Ca2+ binding decreased with increased concentration of the dialysis buffer and on addition of SrCL2, MgCl2 and MnCl2 to the dialysis buffer. Digestion of protein C with trypsin or collagenase or heating of the protein to 60 degrees or 100 degrees C had little or no effect on the Ca2+ binding. Digestion of protein C with alkaline phosphatase caused a decrease in the amount of protein-bound Ca2+. This was also found for another salivary phosphoprotein, protein A. In the absence of Ca2+ the S020,w for protein C was 1.29 S and in the presence of Ca2+ it was 1.46S. Ca2+ may cause a conformational change in the protein or an aggregation of the protein molecules. No conformational changes of protein C in the presence of Ca2+ could be detected by circular dichroism or nuclear magnetic resonance.


The interaction of N-acetylhexosaminidase with insolubilized concanavalin A. The specific interaction between human N-acetylhexosaminidase and concanavalin A was evaluated with respect to temperature, time, pH and concentration of specific ligand in incubation mixtures containing the enzyme and insolubilized lectin. Elution of the enzyme from insolubilized concanavalin A is dependent on both temperature and concentration of alpha-methyl mannoside. Conditions for a high yield of the enzyme from chromatography on insolubilized concanavalin A are described.


Purification of carboxypeptidase B from human pancreas. Carboxypeptidase B of the human pancreas was purified by chromatography on DEAE-cellulose and CM-cellulose columns. Two forms of the enzyme, named carboxypeptidase B1 and B2, were separated. They have similar mol.wts. (34250 +/- 590) as established by polyacrylamide-gel disc electrophoresis and by gel filtration. Carboxypeptidase B2 migrates further towards the anode in disc electrophoresis. When the amino acid content of the enzymes was analysed, carboxypeptidase B2 had four more glycine and three more aspartic acid residues than had form B1. The amino acid sequence of the human carboxypeptidase B1 differs from that of the bovine enzyme only in two places in the N-terminal 20-amino-acid sequence. The N-terminal amino acid in carboxypeptidase B1 and B2 is alanine. The peptide 'map' of the tryptic digest of carboxypeptidase B1 contained more peptides than did that of form B2. The Km, the Vmax. and the pH optimum of the cleavage of the peptide substrate hippurylarginine and the ester substrate hippurylargininic acid were similar for both enzymes. CoCl2 accelerated the peptidase activity, and cadmium acetate enhanced the esterase activity, of human carboxypeptidases B1 and B2. Urea and sodium dodecyl sulphate inhibited the enzymes.


[19F]fluorine nuclear-magnetic-resonance study of the interaction of difluoro-oxaloacetate with aspartate transaminase. Difluoro-oxaloacetate interacts with the aldimine form of aspartate transaminase to give a complex, the dissociation constant of which has been determined spectrophotometrically and by 19F n.m.r. (nuclear magnetic resonance). The 19F n.m.r. line-width-pH and chemical-shift-pH profiles of difluoro-oxaloacetate in the presence of the aldimine form of the enzyme both show inflexion points in the pH5 and pH8 regions, which may arise from variations in the binding of difluoro-oxaloacetate as specific groups on the enzyme are successively protonated. Difluoro-oxaloacetate also interacts with apoenzyme to form a complex, the dissociation constant of which was determined by 19F n.m.r. The 19F n.m.r. line-width-pH and chemical-shift-pH profiles of difluoro-oxaloacetate in the presence of apoenzyme show a single inflexion point in the region of pH8. The absence, in this case, of an inflexion in the pH5 region indicates that the latter, present in the corresponding profiles for the aldimine form of the enzyme, results from ionization of an enzyme group associated with the pyridoxal phosphate cofactor.


The chemistry of the collagen cross-links. Characterization of the products of reduction of skin, tendon and bone with sodium cyanoborohydride. Reduction of tissues with sodium cyanoborohydride at pH7.4 gave results identical with those obtained by KBH4 treatment. On reduction with sodium cyanoborohydride at pH 4.4, however, a previously undetected basic compound was formed and was identified by mass spectrometry and chemical degradation techniques as dihydrohydroxymerodesmosine. Histidino-hydroxymerodesmosine was not present, and further analysis confirmed that reduced aldol, a mojor product of reduction with KBH4 at the lower pH, was also absent. These results, together with an analysis of the time course of the reduction, support previous assertions that histidino-hydroxymerodesmosine is an artifact [robins *Bailey (1973) Biochem. J. 135, 657-665] and suggests that the non-reduced form of hydroxymerodesmosine probably does not constitute a major intermolecular bond in vivo.


Characterization of microsomal choloyl-coenzyme A synthetase. Choloyl-CoA synthetase (EC 6.2.1.7) was characterized for the first time under appropriated assay conditions. The p/ optimum for the reaction is pH 7.2.-7.3. The reaction has an absolute requirement for bivalent cation. Several different metal ions fulfil this requirement, but Mn2+ and Mg2+ were the most effective. The KAppm (apparent Km) for CoA, extrapolated from kinetic data, is 50 micronM, but in fact the rate of reaction is increased little by concentrations of CoA above 25 micronM. The KAppm for ATP is 600 micronM. High concentrations of ATP appear to cause substrate inhibition. The KAppm for cholate was 6 micronM. The enzyme was inhibited by treating the microsomal fraction with N-ethylmaleimide. The inclusion of various conjugated and unconjugated bile salts in the assay also inhibited the enzyme. Unconjugated bile salts were more potent inhibitors than the conjugated bile salts. High concentrations of oleic acid inhibited the enzyme. The properties of choloyl-CoA synthetase were not modified by alterations of the properties of the lipid phase of the microsomal membrane. Treatment with phospholipase A did not alter activity directly. Triton N-101 and Triton X-100 also were without effect on activity, and the enzyme was insensitive to temperature-induced phase transitions within the lipid portion of the membrane. The enzyme can be solubilized from the microsomal membrane in an active form by treatment with Triton N-101.


Chronic nondestructive arthritis associated with cutaneous polyarteritis. Two patients with arthritis of the knee joints associated with cutaneous polyarteritis have been followed for 20 and 5 years. The arthritis is characterized by mild to moderate pain and stiffness and inflammatory joint effusions with predominantly polymorphonuclear leukocytes. Despite its chronicity, there has been no clinical or radiologic evidence of joint destruction. Necrotizing inflammation was seen in arteries of the deep skin but not in the small vessels observed in the synovial biopsy specimens.


Arthritis rounds. Pneumocystis carinii associated with polyarteritis and immunosuppressive therapy. Pneumocystis carinii characteristically causes pneumonia in patients with immunodeficiency disorders. It occurs most often in patients with malignancy or renal transplants whose immune response has been suppressed by corticosteroids or cytotoxic agents. Individuals with connective tissue disease who receive immunosuppressive drugs become susceptible to Pneumocystis. The incidence of Pneumocystis infection in connective tissue disease is low but may increase if immunosuppressive drugs are used more often. Our patient acquired Pneumocystis pneumonia after immunosuppressive therapy for polyarteritis nodosa. Prompt recognition of this condition is essential now that specific therapy is available. Untreated Pneumocystis infection is usually fatal.


[Influence of antirheumatic phenylacetic acid derivatives on glycosaminoglycan metabolism of fibroblast culture (author's transl)]. Murine embryonic fibroblast monolayer cultures were used to study the influence of the antirheumatic phenylacetic acid derivatives ibufanac, ibuprofen, alclofenac and bufexamac and of phenylbutazone as a reference compound on glycosaminoglycan (GAG) metabolism viability and multiplication of cells cultured in vitro. The phenylacetic acid derivatives as well as phenylbutazone showed in concentrations between 10(-3) and 10(-5) M a significant inhibitory effect on GAG production and in concentrations between 10(-3) and 3.3 X 10(-4) M a cytostatic effect; bufexamac was cytostatically active up to the concentration of 10(-5) M. Ibufenac, ibuprofen and alclofenac exhibited a similar behaviour as other non-steroidal antirheumatic drugs regarding their influence of GAG metabolism and on cell multiplication.


[Treatment of coronary insufficiency with beta-receptor antagonists (author's transl)]. The pathophysiology of the coronary insufficiency, the effect of beta-receptor antagonists, the understanding of these effects on the basis of the pathophysiology and the possibilities of testing beta-receptor antagonists in patients with coronary insufficiency are discussed. It is pointed out that the pathophysiology of the coronary insufficiency is based on the difference between oxygen demand of and oxygen supply to the myocardium. beta-Receptor antagonists compensate for this difference. Testing beta-receptor antagonists should include tolerance to exercise and controlled studies using standard medication for comparison.


[Quantitative parameters of sympatho-neuronal and sympatho-adrenal activities in man. The influence of beta-receptor blocking agents (author's transl)]. Determination of both catecholamine concentrations (norepinephrine and epinephrine) and the activity of dopamine-beta-hydroxylase in the plasma of health volunteers and hypertensive patients leads to the conclusion that these parameters used together can be considered an index for sympathetic neuronal activity. However, highly specific and sensitive radiometric methods are necessary for the measurement of these biochemical parameters. In healthy volunteers and hypertensive patients after acute and chronic administration of beta-adrenergic blocking agents, e.g., propranolol, practolol or penbutolol, a significantly higher increase of catecholamine concentrations in the plasma has been observed during physical exercise. This pronounced increase in plasma catecholamine concentrations (mainly norepinephrine) is probably due to an enhanced compensatory sympathetic neuronal activity, accompanied by an increased peripheral resistance; this is obviously necessary in order to maintain a sufficient perfusion of peripheral tissues during work load under the influence of beta-adrenergic blocking agents, since an adequate cardiac output is prohibited by blockade of adrenergic beta-receptors. On the other hand, the pronounced increase in sympathetic tone after beta-blockade, especially after administration of high doses, could be responsible for certain reported side effects, such as hypertensive crisis in psychiatric patients or in patients with phaeochromocytoma.


[Problems of combined therapy with cardiac glycosides and anti-anginal drugs (author's transl)]. The rational use of cardiac glycosides and anti-anginal drugs is deduced on the basis of the pathophysiological interdependence between cardiac and coronary insufficiency. With respect to therapeutic influence on myocardial function and oxygen balance the following rules ought to be regarded: 1. The use of cardiac glycosides should be restricted to patients with cardiac insufficiency in which these drugs are able to reduce the myocardial oxygen consumption due to the hemodynamic consquences of the positive-inotropic action. 2. Organic nitrates and/or beta-receptor blocking agents are compatible with simultaneous cardiac glycoside therapy, but both must be applied according to the individual requirement. 3. Coronary dilators are of questionable value in the therapy of coronary insufficiency, an additional advantage of a combination with cardiac glycosides still has to be proven. 4. There is no rational basis for the use of fixed combinations of these drugs, they do not allow effective and/or safe therapy.


Pulmonary acid aspiration syndrome: should prophylaxis be routine? The gastric contents of three groups of patients were aspirated at the beginning and end of anaesthesia. There were 62 prepared patients, 28 emergency patients untreated and 69 prepared patients who were given 15 ml of 0.3 M sodium citrate mixture at the time of premedication. In approximately 50% of both emergency and prepared patients pH of gastric contents initially suggested the risk of developing acid aspiration syndrome, had inhalation occurred. The proportion of untreated patients in whom more than 40 ml of gastric contents was present at induction and when the tracheal tube was removed were 13% and 31% respectively. The risks were greater in those undergoing upper abdominal operations. Sodium citrate, as used in this study, was shown to be an ineffective antacid. The use of Mist. magnesium trisilicate B.P. as preoperative antacid is urged strongly.


Conditions for tracheal intubation following fazadinium and pancuronium. Intubating conditions were studied in two groups of patients who received either fazadinium 1 mg/kg or pancuronium 0.1 mg/kg (group 1), or either fazadinium 0.5 mg/kg or pancuronium 0.08 mg/kg (group 2). In group 1 intubating conditions were studied at 30, 45, 60 and 75 s after injection of the relaxant drug, and in group 2 at 60 s after injection. Fazadinium provided better intubating conditions than pancuronium during the first 60 s after administration in group 1 (P less than 0.01). In group 2 there was no significant difference between the conditions provided by the two drugs.


The bacteriology of skin cysts.

The bacteriology of skin cysts. Thirty-nine clinically uninflamed cysts of the three most common varieties, epidermoid cysts, trichilemmal cysts and steatocystoma multiplex were removed under sterile conditions and the contents cultured under aerobic and anaerobic conditions. Seventy-three percent of epidermoid cysts grew significant numbers of organisms whereas none of the trichilemmal cysts did so. The organisms found were the common skin commensals, Staphylococcus epidermidis biotype I, anaerobic Gram positive cocci of the Gaffya type and Corynebacterium acnes Type I. This indicates that cysts which clinically have a punctum, namely epidermoid cysts, may become  colonized with surface bacteria under normal circumstances. If they become colonized with pathogenic bacteria they become inflamed, a not uncommon clinical picture. The results from patients with steatocystoma multiplex were difficult to interpret because of the small numbers of patients involved and the unusual clinical appearance they presented.


Salazopyrin in the treatment of scleroderma. Following reports of successful treatment of various forms of scleroderma with salazopyrin, 13 selected patients were treated, 8 with acrosclerosis, one with sclerodermatomyositis and four with generalized morphoea. No effect was observed except in two cases of generalized morphoea which were in the acute stage of spreading to involve most of body surface. These two were more or less cured. This observation seems to warrant further trials with salazopyrin in this rare but serious form of scleroderma.


The effect of zinc and pH on the behaviour of delta-aminolevulinic acid dehydratase activity in baboons exposed to lead. Four adult male baboons (Papio ursinus) were exposed to a cloud of lead oxide dust to induce changes in the status of delta-aminolevulinic acid dehydratase (ALAD). Enzyme activity fell rapidly to a steady state as blood lead levels rose above normal. Exogenous zinc was shown to activate the enzyme, and the antagonistic effect of zinc on in vivo and in vitro lead inhibition was demonstrated for baboons. In baboons not exposed to lead dust, ALAD showed an activity optimum at pH 7-1 which shifted to pH 6-8 with in vitro addition of lead. In baboons exposed to lead dust, with raised blood lead, activity optima were observed at pH 6-8 and 6-2, while the optimum at pH 7-1 was absent.


Beta-adrenergic receptor blocking drugs: tear lysozyme and immunological screening for adverse reaction. Patients who had received long-term therapy with practolol and other beta-adrenergic receptor blocking drugs were examined ophthalmologically. Tear lysozyme concentration and serum autoantibodies (antinuclear antibodies, DNA-binding antibodies and intercellular cement substance antibodies) were measured. It was found that beta-adrenergic receptor blocking drugs may have a pharmacological effect on the lachrymal glands, but this was not associated with dry eyes or adverse reaction. Practolol was found to be capable of reducing tear lysozyme concentrations to very low levels, and  this was initially associated with high titres of ICC antibody. No other drug tested produced these effects.


[Study of properties of NADP malate dehydrogenase from corn leaves]. Kinetic properties of purified chloroplast isoenzyme of the "malic" enzyme from corn leaves were studied. The enzyme had optimum activity at pH 8.0 and 36 degrees C. Under standart conditions the Michaelis constants for the "malic" enzyme with Mn2+ as cofactor are 0.091 mM for malate and 0.04 mM for NADP. In case of Mg2+ as cofactor they are 0.66 and 0.02 mM respectively. Respective Km values for the cofactors Mn2+ and Mg2+ are 0.018 and 0.091 mM. The activity of the "malic" enzyme was inhibited by reduced NADP and NAD, ATP, ADP, fructose-1,6-diphosphate, oxaloacetic, oxalic, glyoxylic, glycolic and alpha-ketoglutaric acids, as well as by phosphate anions and pyrophosphate. The inhibitory effect of all metabolites and ions is more pronounced in case of Mn, rather than Mg, used as cofactors for the reaction. A possibility of metabolic regulation of NADP-"malic" enzyme activity in the leaves of C4-plants, is discussed.


[Inhibition of 4-aminobutyrate transaminase by ethanolamine-O-sulfate]. The analysis of the interaction of ethanolamine-O-sulphate with 4-aminobutyrate transaminase revealed that the inhibitory effect is exerted upon the substrate subsite of the active site of the enzyme in aldimine form. The inhibition in irreversible. The inactivation rate versus pH-curve was shown to have a sigmoid character with inclination point at neutral pH. The study of inhibition kinetics by the Kitz and Wilson method revealed a complex inhibitory pattern compatible with a minimal two-step mechanism. Rate constant of inactivation was found to be equal to 0.22 min-1 and the value of the inhibitory constant--to 1.1-10(-2) M.


[Possible role of acetyl-CoA-carboxylase in biosynthesis of mevalonic acid and sterols in rat liver]. Effect of citrate on acetyl-CoA incorporation into mevalonic acid, sterols and fatty acids after preliminary incubation of rat liver extracts under conditions optimal for acetyl-CoA carboxylase activation, was studied. 30 min preincubation with the citrate at 37 degrees C results in a 2--3-fold stimulation of the mevalonic acid biosynthesis from acetyl-CoA in the microsomal and soluble (140 000 g) fraction, and in that of sterols precipitated by digitonin or isolated by TLC in the mitochondria--free fraction. 2-14C-malonyl-CoA incorporation into the mevalonic acid and sterols and biosynthesis of sterols from 2-14C-mevalonic acid were not stimulated under those conditions. A correlation was shown to exist between the activity of acetyl-CoA carboxylase and the rate of acetyl-CoA incorporation into mevalonate and sterols; the activity of beta-hydroxy-beta-methylglutaryl-CoA reductase, limiting the rate of the sterol biosynthesis, was not changed. The stimulating effect of citrate was found to depend on the concentration of acetyl-CoA and NADPH in the medium. The data obtained suggest that the mevalonic acid biosynthesis in rat liver may occur in the presence of acetyl-CoA carboxylase through the formation of malonyl-CoA.


[Study of betacyanin-discolorating enzyme]. An enzyme catalyzing the discoloration and breakdown of betacyanins was isolated from beet roots Beta vulgaris by centrifugation in sucrose density gradient (2.5 M, 2.0 M, 1.5 M, 1.0 M, tris-HCl buffer, 0.05 M, pH 7.2), and purified 100-fold. The enzyme activity induced the discoloration of betanin, betanidin. It was found that the beet root enzyme exists in an insoluble state and is firmly bound with subcellular structures, which were isolated by centrifugation in sucrose gradient. The optimal activity of the enzyme was observed at pH 3.4, +40 degrees C. The dependence of the enzymatic reaction on the enzyme concentration showed a linearity. Studies of the enzyme inhibition by sodium azide, sodium diethyldithiocarbamate, thiourea, demonstrated that the active site of the enzyme contains a metal. The enzymatic discoloration of betanin is followed by the oxygen uptake.


The turnover rate of gamma-aminobutyric acid in the nuclei of telencephalon: implications in the pharmacology of antipsychotics and of a minor tranquilizer. The turnover rate of GABA is measured in substantia nigra, globus pallidus, N. accumbens, and striatum of rats injected with muscimol, a potent GABA agonist, and diazepam. The similarity of action of the two drugs on GABA turnover further supports the theory that diazepam acts as a GABA-mimetic drug. Haloperidol and clozapine affect GABA turnover differently in different nuclei. Haloperidol decreases GABA turnover in caudate but does not affect that in substantia nigra, whereas clozapine increases GABA turnover in both areas. However, both drugs accelerate GABA turnover in globus pallidus and N. accumbens. It is suggested that an increase of GABA turnover and perhaps of GABA release in striatum and substantia nigra may account for the lack of tardive dyskinesia and extrapyramidal side effects of clozapine.


The actions of amphetamine on neurotransmitters: a brief review. The central stimulant actions of d-amphetamine are not altered in animals in which brain stores of catecholamines have been depleted with reserpine, but they are blocked by alpha-methyltyrosine, which inhibits catecholamine synthesis. The results of a variety of experiments suggest that the central actions of amphetamine result primarily from the ability of the drug to facilitate the release of newly synthesized dopamine from nerve terminals in the forebrain. The results of experiments in animals in which dopaminergic nerve terminals in various brain regions have been selectively destroyed by intracranial microinjection of 6-hydroxydopamine reveal that the locomotor stimulant actions of relatively low doses of amphetamine are dependent upon mesolimbic dopaminergic neurons, whereas the stereotyped behaviors induced by relatively larger doses of amphetamine are dependent upon nigrostriatal dopaminergic neurons. The central actions of amphetamine appear to be the primary result of interactions with dopamine neurons, but secondarily the drug also alters the dynamics of other putative neurotransmitters (e.g. acetylcholine, 5-hydroxytryptamine) in the brain.


Effect of heparin on complement activation and lysis of paroxysmal nocturnal hemoglobinuria (PNH) red cells. The effect of heparin upon the binding of the third component of complement (C3) to PNH red cells in vitro and their subsequent hemolysis is described. Heparin, in increasing concentrations, progressively inhibits membrane C3 fixation and hemolysis when the classic complement pathway is activated by anti-red cell antibodies. Heparin has a biphasic effect upon membrane C3 fixation and hemolysis when complement is activated in serum at decreased ionic strength (sucrose lysis) or in serum at decreased pH (Ham test). Heparin in concentrations above 2 U/ml inhibits C3 binding and hemolysis while lower concentrations of heparin enhance the consequences of complement activation by these two procedures. This enhanced complement activation may explain the increased hemolysis sometimes reported in PNH patients treated with heparin, and suggests that heparin may aggravate the consequences of pathologic alternative pathway complement activation in other diseases.


Metabolic crowding effect in suspension of cultured lymphocytes. We studied the respiration and glucose utilization of suspensions of cultured lymphocytes. Respiration was measured by a couloximetric method using closed systems without a gas-suspension interface. The sensitivity of the method allowed measurements during a time interval of less than 1 hr. We found that the respiration of lymphocytes was strongly density dependent over the range of 10(8)-10(3) cells/ml. Oxygen utilization per cell increased 100-fold with 1000-fold dilution of the cell suspension. Glucose utilization showed little density dependence. We showed that the phenomenon was not due to nutrient depletion, pH shifts, accumulation of lactic acid, nor damage of cells during the dilution. Since in our experiments a gas-liquid interface was absent, the previously suggested explanation of gas diffusion as a limiting factor has been excluded. The experiment was best explained by regulation of respiration by humoral factors produced by the cell suspension.


Influence of H+ on K+ on adenosine-induced dilatation at pial arteries of cats. The influence of changes in the perivascular K+ and H+ concentrations upon adenosine-induced dilatations of pial arteries was investigated by localized perivascular application using micropuncture technique. Adenosine (10(-9)-10(-3) M) was dissolved in mock spinal fluids with varying bicarbonate and potassium concentrations (5 and 22 mM HCO3-, and 6 and 10 mM K+). Concentration response curves revealed that adenosine induced the same change in pial arterial diameter when dissolved either in an inert (11 mM HCO3-) or in a constrictory (22 mM HCO3-) mock spinal fluid. However, adenosine, when dissolved in a more acidic or higher potassium-containing solution (5 mM HCO3-, or 6 or 10 mM K+) produced a diminished dilatatory effect. It is concluded that, for a quantification of the individual contributions of several metabolic factors in the regulation of vascular resistance, it is necessary to consider their interactions.


Observations on the behaviour of barium sulphate suspensions in gastric secretion. A number of barium sulphate suspensions showed varying patterns of stability when provoked with gastric secretion. The stability of the suspensions was affected by the pH, the mucin content and the volume of secretion used. These studies indicate that flocculation of the suspension in the presence of gastric residue decreases as the amount of undiluted barium sulphate in the mixture is increased.


Cardiovascular and sympathetic response to exercise after long-term beta-adrenergic blockade. The response to dynamic exercise was investigated in 21 patients receiving long-term treatment with beta-adrenoceptor antagonists and 22 controls. An electrocardiogram (ECG) and blood pressure were recorded before and after treadmill exercise, and plasma dopamine-beta-hydroxylase (DBH) activity was measured as an index of changes in sympathetic activity. Heart rate and blood pressure were lower at rest and throughout exercise in treated patients, although the pressor effect of exercise was not reduced. The ECG P-R interval was lengthened, and in addition the Q-T interval was prolonged. After exercise, plasma DBH activity was significantly increased in controls but not in treated patients. We conclude that long-term administration of beta-adrenergic blockers increases myocardial repolarisation time and reduces sympathetic nervous activity. These actions may contribute to the antiarrhythmic and hypotensive effects of long-term beta-blockade.


Release of a neurodepressing hormone from the crustacean sinus gland. The nervous system of the crayfish contains a peptide of low molecular weight which depresses the spontaneous electrical activity of motoneurons in the abdominal ganglia. Most of this substance is contained in the sinus gland, a neurohemal organ in the eyestalk. Electrical stimulation of the isolated sinus gland, or its incubation in potassium-rich solutions (20--80 mM) results in the release of the neurodepressing peptide. The release is calcium-dependent and appears to involve a process of exocytosis. The released product shows electrophoretic properties undistinguishable from the substance present in the sinus gland.