Communication patterns of doctors and their assistants. Communication patterns between physicians and their assistants (Medex) were observed in 19 practices to describe and evaluated the nature of their relationship. Observations demonstrated that interaction around patient problems was approximately 30 minures per day and informal, with the Medex more often initiating the contact. Medex were more likely to ask for, and physicians were more likely to give, suggestions. Physicians appeared to regard the accomplishment of the immediate task as more important than maintaining good relations. In most practices, supervision was available when requested. Generally, both the physician and the Medex show a striking similarity in communication styles.


Sterol synthesis in the liver, intestine, and lung of the guinea pig. The relative rates of sterol synthesis in the liver, ileum, and lung of the guinea pig have been studied by measuring the incorporation by tissue slices of 14C-labeled acetate into digitonin-precipitable sterols. The liver showed maximum incorporation of acetate at pH 6.5, the ileum at pH 7.5, and the lung at pH 6.0. The incorporation of acetate approached the maximum rate at a concentration of 10 mM with the liver and lung and 5 mM with the ileum. Using these conditions of assay, sterol synthesis was measured in the liver, ileum, and lung of four groups of guinea pigs killed at 6-hourly intervals. Depending on the time of day, the rate of sterol synthesis in the ileum was from 6 to 14 times that in the liver, while in the lung the rate was up to 3 times that shown by the liver, Additional studies showed that all regions of the small intestine synthesized sterol at a higher rate than the liver, with the highest rate of synthesis occurring in the ileum. The rates observed in the adrenal, testis, muscle, adipose tissue, and skin indicated that these tissues are not quantitatively important sites of sterol synthesis in the guinea pig.


Autoregulatory system of insulin degradation in liver. II. Relationship between blood insulin levels and GSH-dependent insulin degrading activity in liver and blood. An autoregulatory system of insulin degradation in the liver in which the rate of insulin metabolism changes in response to fluctuation in its blood levels, was investigated. In the plasma of rats and man in the absence of reduced glutathione (GSH), insulin degradation was not observed, but when a sufficient amount of reduced glutathione was added, the plasma did degrade insulin. This GSH-dependent insulin degrading activity in plasma was quite similar to that in liver in its nature. In rats, this GSH-dependent insulin degrading activity in the liver and plasma was fluctuated in  response to fluctuation in the blood insulin levels, and the GSH-dependent insulin degrading activity in plasma was well correlated with that in the liver. Similarly, in man the GSH-dependent insulin degrading activity in plasma was changed in response to fluctuation in the blood insulin levels. In plasma under the physiologic conditions, there is an insufficient amount of reduced glutathione to elicit the insulin degrading activity, but in the liver there is a sufficient amount of reduced glutathione to manifest this activity. This evidence further supports the concept that an autoregulatory system of insulin degradation in the liver exists in man.


Envelope mutation promoting autolysis in Salmonella typhimurium. Two strains independently isolated in Salmonella typhimurium display abnormal autolytic activity when nutrient broth becomes alkaline. They also show increased sensitivity to deoxycholate, EDTA, and sodium dodecyl sulfate. Response to acridine orange remains normal. In both strains a single stable mutation is responsible for all the changes. The same gene, called envD, appears to be involved in both mutant strains. envD has been located at minute 33 of the Salmonella genetic map, between markers sucA and nadA, very close to the latter. envD also affects morphological characteristics of the cells. Many mutant cells are shorter than wild type bacteria, and appear frequently associated in short chains of 4 to 10 cells. Furthermore, envD mutants display division by septation under conditions that preclude its observation in wild type strains.


Ferredoxin-dependent photosynthetic reduction of nitrate and nitrite by particles of Anacystis nidulans. The dark and light reduction of nitrate and nitrite by cell-free preparations of the blue-green alga Anacystis nidulans has been investigated. The three following methods have been successfully applied to the preparation of active particulate fractions from the alga cells: (a) shaking with glass beads, (b) lysozyme treatment and lysis of the resulting protoplasts, and (c) sonication. The two enzymes of the nitrate-reducing system-namely, nitrate reductase and nitrite reductase-are firmly bound to the isolated pigment-containing particles, and can be easily solubilized by prolonging the vibration or sonication time. Both enzymes-whether solubilized or bound to the particles-depend on reduced ferredoxin as the immediate electron donor. In its presence, the alga particles catalyze the gradual photoreduction of nitrate to nitrite and ammonia, a process that can thus be considered as one of the most simple and relevant examples of Photosynthesis. Some of the properties of nitrate reductase have been studied. Nitrate reductase as well as nitrite reductase are adaptive enzymes repressed by ammonia.


Appearance of a syndrome similar to graft versus host reaction in C57 B1/6 mice bearing skin allogenic graft. A syndrome similar to GVHR is described in mice of C57B1/6 strain during the WHT/Ht skin allografts rejection period. In all the cases the described thymus involution was associated with the hypertrophy of lymph nodes. Their volume increase is due to the high number of blastic pyroninophilic and plasma cells concomitant with small lymphocytes depletion in the cortical area, and with a very pronounced hypertrophy of medullary cords by presence of a high number of plasmocytes and blastic cells. These changes have been noticed only in some animals sacrified during the first days after grafting and never later one. In agreement with the scarce data of the literature, we think that the immunocompetent passenger lymphocyte comprised in the skin grafts constitute an immunologic organ able to induce a GVHR at the beginning of the period of graft survival on the host. This GVHR, generally mild and without clinical and microscopic signs, becomes obvious only in animals which, for unknown reasons, present a low immunologic defense capacity. In these animals the described process seems to be reversible.


[Mycoplasma-like micro-organisms in malignant tumors and non-tumours dermatovenerological diseases. Electron microscopic investigations (author's transl)]. In examination of the ultrastructure of excised tissue and other material from patients with various diseases, principally dermatovenerological affections and with malignant tumors, and in healthy control subjects, patterns suggesting mycoplasma were repeatedly found in certain diseases only. Specific attempts to isolate mycoplasma from the material were made, in which previously patterns of a mycoplasma type had frequently been seen. It was possible to culture mycoplasma-like organisms in vitro from patients with the following diseases: malignant melanoma, mycosis fungoides, prickle cell carcinoma, squamous cell carcinoma, non-specific urethritis, pemphigus erythematosus, panarteritis nodosa and vasculitis allergica cutis.


[Chemical Investigation of Chronic Pancreatitis]. We differentiate indirect and direct methods. The indirect methods include the examination of the blood (ESR, blood picture, electrolytes, especially calcium, for the exclusion of hyperparathyroidism, status of fat and liver enzymes, activity of alpha-amylase and lipase. More informative than a serum determination is the measurement of the amylase activity in the 24-hour urine. The detection of chymotrypsin in the stool can be recommended as an investigative test also for use in general practive in collaboration with a central laboratory.- The direct methods include investigation of the duodenal juice with measurement of pH, bicarbonate, of the activities of chymotrypsin, trypsin, lipase and amylase. For excluding of a disturbance of the carbohydrate metabolism in addition to blood sugar determinations, glucose tolerance and tolbutamide tests, the determination of insulin activity is indicated.


Huntington's chorea. Changes in neurotransmitter receptors in the brain. Neurotransmitter-receptor binding sites for apparent muscarinic cholinergic, beta-adrenergic, gamma-aminobutyric acid and serotonin receptors were measured in the caudate nucleus and frontal cerebral cortex from post-mortem brains of 16 patients with Huntington's chorea and 16 controls. In addition, the samples were assayed for the gamma-aminobutyric-acid-synthesizing enzyme, glutamic acid decarboxylase, and for the acetylcholine-synthesizing enzyme, choline acetyltransferase. In the caudate nucleus of choreic brain, both enzyme activities were markedly lower, with significant decreases in muscarinic cholinergic and serotonin receptor binding, whereas enzyme activities and receptor binding were unchanged in the cerebral cortex. By contrast, gamma-aminobutyric acid and beta-adrenergic receptor binding were not significantly different in choreic and control caudate nucleus or cortex, suggesting that, despite the loss of gamma-aminobutyric-acid-synthesizing ability in the corpus striatum, gamma-aminobuytric acid mimetic drugs might alleviate the movement disorders in Huntington's chorea.


[The effect of changes in the pH of the external solution on the afterpotentials of individual frog nodes of Ranvier]. A decrease in pH to 5 elicited a small increase in afterdepolarization of a single Ranvier node and an increase in pH to 9 had no effect. Post-tetanic hyperpolarization decreases at pH 5 and its duration somewhat increases. An increase in pH to 9 also had no effect. Similar changes in afterdepolarization and post-tetanic hyperpolarization were observed in potassium free solutions. A conclusion is made that changes in afterpotentials are determined by changes in kinetics of the membrane potassium permeability.


Prolonged clinical and experimental follow-up of hospitalized schizophrenics. 148 chronic schizophrenics admitted between 1938 and 1961 had previously been followed up. In 1972, they were re-examined, on the average 10 years after the first follow-up. 44 belonged to a series of patients studied between 1955 and 1957 with a battery of conditional reflex tests. The patients belonging to the experimental series were retested with word associations. From an experimental point of view the patients performed better over the prolonged observation period. The clinical state also showed improvement. A comparison of the chronic hospital population during 1955-57 and 1972-74 suggests that the new chronics present much less of the severe schizophrenic deterioration than the old ones. They also have remarkably better verbal functions these changes are assumed to be mainly due to drug treatment. The beneficial effects of drugs appear to come mainly within the first 2 years.


[The state of prothrombin, plasminogen and fibrinogen in the newborn infant]. The esterase activity of thrombin and plasmin on artificial substrates was used to study the kinetics of these enzymes by Lineweaver and Burk's method. In the plasma of new-born infants, plasmin obtained from streptokinase has an avidity comparable with that in adults. Thrombin is obtained by the action of staphylocoagulase and taipan venom. Its avidity has important individual variations and is different from that in adults. An inhibitor is present both in the plasma and in the serum of the new-born. Fibrinogen was studied by variations in absorption of light during coagulation by thrombin. The abnormalities observed depend on the physical and clinical conditions of the medium (ph, osmolality). These characteristics depend on the age of the infant, but also seem to depend on the conditions of the sample and, in particular, on fibrinolytic reactions. The existence of foetal fibrinogen is discussed.


Local renal graft-versus-host reaction: sequential ultrastructural study. A sequential study has been made of the ultrastructure of local renal graft-versus-host reactions produced in cyclophosphamide-pretreated rats by injection of either allogeneic or xenogeneic (mouse) spleen cells beneath the renal capsule. Early in the reaction, immunoblasts were seen between the outer cortical tubules, and there was associated interstitial oedema and tubular degeneration. In places, several small lymphocytes were observed clustered around and in close cytoplasmic contact with individual immunoblasts, perhaps representing interaction between donor and host cells. As the reaction proceeded, the number of lymphoid cells increased by immigration from peritubular vessels. Some tubules were invaded by lymphocytes but this was not closely related to the development of tubular injury. The reaction was maximum at one week and then decreased. Now, there was greater diversity of cells including macrophages, plasma cells and eosinophils, while many lymphoid cells became necrotic. It is concluded that most of the renal parenchymal injury is due to chemical mediators liberated from the infiltrating cells rather than to ischaemia or direct cytoplasmic interaction between leucocytes and tubular epithelium.


Functional abnormalities in renal cystic diseases. The functions of a kidney, whether normal or cystic, can be conceptualized in terms of anatomy (glomerulus, proximal tubule, loop of Henle, distal convolution, and collecting duct), activity (volume regulation, dilution and concentration, acid-base regulation, potassium excretion, transport of organic molecules, and calcium and phosphate excretion), and the integration of anatomic organization to meet functional demand. Our discussion of renal cystic disorders follows this conceptual outline. For discussions of normal renal physiology, the reader is referred to any one of several recent, excellent reviews (1-3). Systematic evaluation of renal function in cystic diseases of the kidney (medullary sponge kidney, medullary cystic disease, and polycystic kidney disease) has only rarely been performed. The available information suggests that the earliest detectable lesions consist primarily of tubular dysfunction. With time, however, significant reduction of glomerular filtration occurs and the resultant accumulation of uremic toxins dominates the clinical picture in polycystic and medullary cystic disease. Significant changes in glomerular function are unusual in medullary sponge kidney. This review represents an attempt to summarize the large body of literature that has accumulated on functional abnormalities in these disorders, and to point out those areas where further investigations are needed.


Phosphate transport by isolated renal brush border vesicles. A sodium dependent specific transport system for phosphate is present in the brush border microvilli but absent from the basal-lateral plasma membranes. The apparent affinity of this transport system for phosphate is 0.08 mM at 100 mM sodium and pH 7.4. It is inhibited competitively by arsenate with an apparent inhibitor constant of 1.1 mM (100 mM sodium, pH 7.4). Sodium dependent phosphate uptake is two times higher at pH 8 compared to the uptake observed at pH 6. The apparent affinity of the transport system for sodium is also pH-dependent, half-maximal stimulation of uptake is found at pH 6 with 129 mM sodium, at pH 7.4 with 60 mM sodium and at pH 8 with 50 mM sodium. Under all conditions a nonhyperbolic dependence of phosphate uptake on the sodium concentration is observed. The uptake of phosphate by brush border microvilli vesicles shows a typical overshoot phenomenon in the presence of sodium gradient across the membrane (CNao greater than CNai). The amount of pohsphate taken up after 2 min is about twice the equilibrium value reached after 2 h of incubation. At pH 7.4 the initial rate of uptake is increased only slighyly (12%) by inside negative membrane diffusion potentials and inhibited to the same extent by inside positive membrane diffusion potentials. These results indicate that the entry of phosphate across the brush border membrane into the epithelial cell of the proximal tubule is coupled to the entry of sodium. The transfer of phosphate is dependent on its concentration gradient and on the concentration difference of sodium. The data are best explained by the following hypothesis: Both the primary phosphate as well as the secondary phosphate are transported in cotransport with sodium. The divalent form however seems to be transported preferentially. Its transport occurs electroneutral with 2 sodium ions; the monovalent phosphate also enters the cell together with 2 sodium ions but as a positively charged complex. The exit of phosphate across the contraluminal cell border is sodium independent and is favoured by the high intracellular phosphate concentration and the inside negative membrane potential.


The effect of carbonic anhydrase inhibition on bicarbonate reabsorption. Renal reabsorption of bicarbonate was studied in Merino ewes during carbonic anhydrase inhibition. Bicarbonate reabsorption was directly proportional to plasma bicarbonate concentration. No tubular maximum for bicarbonate was demonstrated. Elevation of arterial PCO2 or depression of arterial pH caused slight increases in bicarbonate reabsorption. The data suggest that bicarbonate is reabsorbed by 2 distinct processes. The quantitatively more significant process may involve ionic reabsorption of bicarbonate secondary to Na+ reabsorption and a relatively minor part of bicarbonate reabsorption may be secondary to H+ secretion.


Atherosclerotic cerebral infarction: pathophysiologic aspects. When the supply of substrate to the brain is threatened, homeostatic mechanisms induce cerebral vasodilatation to compensate for the insufficiency. When a region of the brain is rendered completely ischemic, local infarction occurs. The size of the infarct depends partly on the availability of collateral circulation and the adequacy of the homeostatic mechanisms controlling blood flow in stillpatent vessels. Several approaches to acute-phase treatment of stroke derive from clinical and experimental studies of cerebral blood flow and metabolism. We must conclude that both surgical and nonsurgical therapeutic measures have been of limited value in the treatment of cerebral infarction and that the basic therapy for completed stroke remains good medical management of complications and attentive nursing care.


Pharmacologic therapy of asthma.

Pharmacologic therapy of asthma. Asthma is treated by avoiding the precipitants of symptoms, by a trial of hyposensitization (immunotherapy) if the precipitant cannot be avoided, and principally by pharmacologic therapy. Acute attacks have been most widely treated with epinephrine, but adrenergic aerosol bronchodilators and aminophylline are being used increasingly. When an acute attack of asthma does not respond to treatment, a diagnosis of status asthmaticus should be considered and the patient treated in a hospital intensive care unit because of the potentially life-threatening sequela of respiratory failure. Periodic mild episodes of asthma usually respond to administration of an oral bronchodilator. Chronic low-grade asthma is best treated with an around-the-clock regimen of theophylline. Patients whose asthma is not under satisfactory control with conventional bronchodilators may be given a trial of cromolyn sodium. Chronic severe cases may be treated with corticosteroids, but these drugs must be skillfully administered to avoid adverse effects.


Managing acute urticaria.

Managing acute urticaria. The physician should be familiar with preventive measures for acute urticaria or its most severe form, anaphylaxis, and with the general principles of management. Treatment does not differ basically whether given in a nonmedical setting, the emergency room, or the office, except for the availability of special supplies and equipment, such as oxygen, if needed. In all cases, a history should be obtained quickly, the patient should be examined to confirm the diagnosis, and epinephrine should be administered. Hospitalization is indicated in severe cases with systemic symptoms. Once the acute episode has been treated, the physician must decide whether further investigation is necessary. Quite often a presumptive etiologic diagnosis is made on the basis of the history. Allergy testing is not part of the routine evaluation of the patient with urticaria.


Myocardial ischemia from coronary arterial spasm. Spasm of coronary arteries can cause chest pain indistinguishable from classic angina pectoris in patients without atherosclerosis of these vessels or recognizable heart disease. Associated electrocardiographic changes usually correspond to the coronary artery affected and disappear when the attack of pain ends. Sublingual nitrates are excellent agents for the control of the episodic anginal symptoms. There have been scattered reports of myocardial infarction occurring in patients with normal coronary arteries; a role of arterial spasm in these cases in speculative.


Preparation of drugs used in hyperacidity. Part I. Effects of pH of precipitation on the neutralizing properties of alumina gels. Alumina gels were obtained from sodium aluminate by addition of 3 N HNO3, HCl or H2SO4 solutions or by saturation with gaseous CO2. The effect of several physicochemical factors (pH of precipitation, kind and concentration of precipitating agent, temperature) on the neutralizing properties of the obtained forms of Al(OH)3 was investigated. The linear correlation between the pH of precipitation and the neutralizing properties was found. The effect of different precipitating anions on the acid-consuming capacity and the rate of neutralization of 0-1 N HCl was established.


Nephron function in acute glycerol-induced renal insufficiency in rabbits. The effect of acute experimentally induced renal failure after intramuscular injection of glycerol on serum and urine GGTP, LAP and AP activities was studied in 30 rabbits. High doses of glycerol caused shock, myolysis and hemolysis, leading to acute renal insufficiency. Serum urea and creatinine levels significantly increased, there was proteinuria, and significant decrease in 24-hr diuresis, glomerular filtration, and urinary urea excretion. The changes in LAP and AP activities were significant, and in GGTP-nonsignificant. In the urine GGTP and LAP increased significantly, and AP nonsignificantly. Urinary excretion of AP increased significantly, and GGTP and LAP nonsignificantly. The highest activity and urinary excretion of GGTP and LAP were observed on the 2nd day, and of AP--on the 5th day of renal failure.


Angina pectoris. Diagnosis and treatment. The physician who understands the pathophysiology of angina pectoris can apply rational therapeutic measures based on an appreciation of the determinants of myocardial oxygen supply and demand. Most patients with angina secondary to coronary atherosclerosis can be treated conservatively using a systematic approach that includes correction or removal of underlying causes or precipitating factors and the judicious use of sublingual nitroglycerin. In patients with more resistant angina, use of oral or topical nitroglycerin or sublingual isosorbide dinitrite as well as propranolol can be advised. Aortocoronary bypass surgery can offer significant improvement in carefully selected patients with frequent angina poorly controlled by medical therapy. The most important consideration in the treatment of angina is protection of coronary blood flow reserve by primary prevention of the atherosclerotic process itself. All individuals from families prone to coronary artery disease should be evaluated for alterable risk factors, the most important being cigarette smoking, hypertension, and hypercholesterolemia. Considering the high risk of unheralded sudden death in previously asymptomatic patients with coronary atherosclerosis, angina can, in a sense, be considered a fortunate harbinger of coronary stenosis, identifying candidates for secondary preventive measures aimed at retarding the progression of vascular disease. More importantly, angina serves as an index for detecting families at high risk of coronary artery disease, in whom early application of primary prevention may afford a more promising outlook.


Intranasal beclomethasone dipropionate in seasonal rhinitis in general practice. Thirty-five patients with seasonal allergic rhinitis were treated in a double-blind comparative trial in and East London Group Practice with either beclomethasone dipropionate (50 micrograms in each nostril four times a day) or a placebo aerosol preparation identical in appearance. There was a statistically significant difference in favour of intranasal beclomethasone dipropionate (P less than 0-05).


[Cerebral palsy--early diagnosis and treatment (author's transl)]. The main aim of the present Conference has been to debate that early diagnosis and treatment of cerebral palsy. The Conference was attended by specialists taking care of the child with cerebral palsy (C.P.): child neurologists, surgeons--orthopedists, psychologists, rehabilitants, pediatricians. In connection with the fact that the Conference was devoted to the early diagnosis and therapy of C.P., problems concerning the lower age groups of children were debated. The Conference discussed the definitions of "cerebral palsy" used in the literature, the clinical forms, the auxiliary diagnostic methods and their significance in the diagnosing of this pathological syndrome. Early clinical symptoms, enabling to establish the diagnosis of cerebral palsy were particularly extensively debated. In the latter problem particular attention was paid to the diagnostic value of kinetic automatisms of the group of tonic posture reflexes and dysfunctions of the kinetic pattern in children. It was underlined in the debate the C.P. was no separate clinical disease, but a pathological syndrome arisen as a result of the negative influence of different factors and yielding very diverse clinical and neurolopathologic symptoms, according to the kind of noxious factors and the period and degree of maturity of the nervous system in which they acted. The participants in the debate also sressed that, as the child develops and is observed for a longer period it is fairly often necessary to check this diagnosis, as C.P. may prove, as the time passes, to be a degenerative syndrome, a pressure syndrome etc. The psychologists participating in the Conference discussed the psychological problems of the child with C.P. and also the early diagnosis of the pathological syndrome debated. The diversity of the symptoms of the C.N.S. in children suffering from C.P. was underscored, as--apart from dysfunctions within the kinetic area, there can be present sight, hearing and speech dysfunctions, those of sensory perceptions and mental development. These children require multispecialist care, as everyone of dysfunctions mentioned may present a complicated diagnostic problem. Plenty of place was devoted to the discussion of problems connected with epilepsy in children with C.P. Also extensively debated were the general principles of the medical procedure in children with C.P. As a result of the discussion it was decided that children with severer forms of C.P. and those from poor social conditions should be subjected to long-lasting sanatorium rehabilitation. Keeping the child in its family environment should, however, be the generally adopted principle of the rehabilitation of a little child. The parents of the child should be trained in the proper rearing of the child under household conditions, a manner to secure all the needs resulting from the then stage of its development. In connection with this problem the project of the programme of sensoric-and-kinetic rehabilitation was debated, as presented by psychologists and rehabilitants (kinesitherapeuts).


[Congenital heart malformations in neonates, infants and young children (author's transl)]. Congenital heart malformations in neonates, infants and young children represent the main problem of paediatric cardiology in Poland. Congenital cardiovascular diseases (incidence also approximately 8 per 1000 in liveborn infants) cause very high mortality, particularly in the neonatal and infantile period. Approximately 5000 live-born children are affected every year by serious heart malformations. For at least two thirds of these previously hopelessly ill infants there are real possibilities of effective medical and surgical treatment. Not only a considerable drop in mortality in the earliest infancy would be achieved, but: a further normal physical and psychical growth and development of these children would be possible. At present, however, the available possibilities are by far not sufficient, as in all hitherto functioning centres we were able to manage 200-300 children yearly, whereas the real needs are at leasttenfold greater. Therefore it is necessary to: Increase the number and capacity of hospital wards capable enough to provide the intensive cardiopulmonary care; to execute appropriate reorganization aimed to concentrating the appropriate specialists (pediatric cardiologists, radiologists, surgeons, anesthesiologists, nurses) and equipment (cardiological and cardiosurgical appliances, X-ray equipment, intensive care units etc.) in centres designated for the above tasks. At least 7 paediatric intensive care and cardiosurgical centres should be instituted in Poland for a satisfactory management of congenital heart diseases.


[Ribonuclease activity in the serum of children of various ages (author's transl)]. The normal levels of ribonuclease activity in the serum of children of both sexes of various ages. The children into four age groups: thee 1st grous--from 1 to 7 days of age, the 2nd--from 1 to 12 months, 3rd--from 1 to 3 years, 4th--from 7 to 14 years of age. The ribonuclease activity amounted, in the various age groups, respectively tto: 1st group--0.27+0.07 ug/ml of serum, 2nd--0.21+0.06 ug/ml, 3rd--0.15+0.04 ug/ml, 4th--0.14+0.04 ug/ml.


Activation and nuclear translocation of protein kinase during transsynaptic induction of tyrosine 3-monooxygenase. The tyrosine-3-monooxygenase activity [L-tyrosine, tetrahydropteridine: oxygen oxidoreductase (3-hydroxylating); EC 1.14.16.2] of rat adrenal medulla is induced 20-24 hr after the injection of reserpine (16 mumol/kg intraperitoneally). This and other inducing stimuli increase the 3': 5'-cyclic AMP (cAMP) content in the medulla for longer than 60 min and activate the cAMP-dependent protein kinase (ATP: protein phosphotransferase; EC 2.7.1.37) for several hours. Corticotropin (ACTH), dopamine, and propranolol do not induce the monooxygenase, but elicit an increase in the cAMP content of the medulla which fails to activate protein kinase and lasts less than 1 hr. A high- and low-molecular-weight protein kinase are separated by gel filtration from the 20,000 X g pellet extract of adrenal medulla homogenate. The activity of the low-molecular-weight enzyme is expressed as its ability to phosphorylate histone. The protein kinase activity of the pellet is increased between 3 and 17 hr after reserpine injection. Our evidence indicates that this increase is due to a translocation from cytosol to subcellular structures of a kinase that utilizes lysine-rich histone as phosphate acceptor. The protein kinase activity that is extracted from a purified nuclear fraction prepared from the adrenal medulla of rats injected 7 hr previously with reserpine is greater than that extracted from medulla of saline-treated rats.


A 15-hydroxyprostaglandin dehydrogenase specific for prostaglandin A in rabbit kidney. Examination of a soluble fraction derived from homogenates of rabbit kidney papilla revealed the existence of a 15-hydroxyprostaglandin dehydrogenase specific for A-type prostaglandins. Prostaglandins of the E- and F-series were not substrates for this enzyme. In agreement with published data, the 15-hydroxyprostaglandin dehydrogenase(s) derived from the kidney cortex were found to degrade all prostaglandins examined (PGE, PGF, PGA) in the presence of added cofactor NAD. Thus it is evident that in this species the kidney 15-hydroxyprostaglandin dehydrogenases are anatomically compartmentalized so that the papilla is able to metabpable of degrading E-, F-, and A-type prostaglandins by this metabolic pathway.


Specific positions involved in enzyme catalyzed covalent binding of benzo[a]pyrene to poly(G). Covalent binding of benzo[a]pyrene to poly(G) was studied with the use of a radioactive assay and specifically labeled substrates to define the role of the 1, 3- and 6-positions of the hydrocarbon during this process. Binding was shown to be dependent on microsomes, NADPH, O2 and poly(G). 7, 8-Benzoflavone and 2', 2'-diethylaminoethyl-2, 2-diphenyl valerate were inhibitory w.hereas modulators of epoxide hydrase activity had little effect. 3H and 14C studies suggested a possible loss of one to two protons. Incorporation of [6-3H1]benzo[a]pyrene provided evidence that the 6-position of the hydrocarbon was not metabolized during covalent attachment to poly(G) and, furthermore, results with [1, 3, 6-3H]benzo[a]pyrene suggest that the 1- and 3-positions may not be involved either. After scaling up of the standard assay 20-fold, characterization of the tritiated BaP-poly(G) complex was carried out by hydrolysis and subsequent chromatography. Thin-layer chromatography of the isolated hydrolysis products treated with HCl or alkaline phosphatase indicated that the complex formed between BaP and poly(G) was covalently linked and composed of hydrocarbon-nucleotide(s).


Simple model for hormone-activated adenylate cyclase systems. A simple model is developed to explain the activation of rat liver plasma membrane adenylate cyclase [ATP pyrophosphate-lyase (cyclizing), EC 4.6.1.1] by guanosine nucleotides and glucagon and the dependence of the cATALYTIC RATE ON Mg2+, H+, and substrate concentrations. The basic model proposes that the adenylate cyclase system can exist in two states, A and B; that activating ligands bind preferentially to the B state; and that only the B state is active. Kinetic data are quantitatively fit to this model, and the binding constants for the interaction of the A and B states with glucagon, GTP, and guanyl-5'-ylimidodiphosphate are obtinaed. The substrates ATP and adenyl-5'-ylimidodiphosphate appear to show little preference between the A and B states, and simple Michaelis-Menten kinetics are sufficient to describe the dependence of the catalytic rate on substrate concentration under optimal conditions. The dependence of the rate on pH can be explained by postulating that one ionizable group in its acid form and one ionizable group in its basic form must be present at the active site in order for catalysis to occur. The activation and inhibition of the activity by Mg2+ can be explained by a similar mechanism with Mg2+ binding to activating and inhibiting sites. Glucagon and guanosine nucleotides appear to influence the dependence of the rate on Mg2+ and glucagon. The Mg2+ also may display some preference for the B state. A comparison of this model with others that have been proposed is given. The proposed model appears to provide a simple conceptual frame-work that is applicable to many adenylate cyclase systems.


Heat mutagenesis in bacteriophage T4: the transition pathway. G-C leads to A-T transitions are induced by heat, and arise from the deamination of cytosine (5-hydroxymethylcytosine in the case of bacteriophage T4) generating uracil. The reaction is proton-catalyzed, and is also characteristic of acid mutagenesis. Mutation rates and activation energies of mutation are site-specific, and are presumably influenced by neighboring bases. Rates of heat-induced mutation in bacteriophage T4 under conditions of temperature, pH, and ionic strength similar to those prevailing in higher eukaryotic cells suggest that heat mutagenesis may present a serious challenge to organisms with large genomes, and may comprise an important determinant of the rates of spontaneous mutation.


beta-adrenergic receptors in rat liver: effects of adrenalectomy. The response of rat liver adenylate cyclase [ATP pyrophosphate-lyase (cyclizing), EC 4.6.1.1] to catecholamines is enhanced after adrenalectomy. To investigate this phenomenon, we developed an in vitro assay for beta-adrenergic receptors of plasma membranes derived from livers of control and adrenalectomized rats, using [125I]iodohydroxybenzylpindolol (IHYP), a potent beta-adrenergic receptor antagonist. Binding of IHYP reached equilibrium within 30 min and dissociation occurred with a half-time of approximately 60 min. The l-isomers of isoproterenol and propranolol were at least 50 times more potent as inhibitors of IHYP binding than were the corresponding d-isomers. Adrenalectomy did not affect the rates of association or dissociation of IHYP or the dissociation constants of several ligands that are active at beta-adrenergic receptors. The number of binding sites for IHYP was determined in homogenates and in purified membranes of livers from control and adrenalectomized rats. The number of sites increased 3- to 5-fold after adrenalectomy. A similar increase in hormone stimulation of adenylate cyclase was observed. These changes were reversed by the administration of cortisone. The increase in the number of binding sites for IHYP may be a compensatory response to the impairments in gluconeogenesis and glycogenolysis which occur after adrenalectomy.


Thermodynamic studies of polymerization of deoxygenated sickle cell hemoglobin. Solubilities of deoxygenated sickle cell hemoglobin (deoxy-Hb S), at varying pH and temperature over a range of concentrations encompassing those found in erythrocytes, were measured. The technique involved ultracentrifugation, which gave values of the supernatant concentration and the mass of the sedimented material. The data establish that the solubility of doexy-Hb S is the saturation concentration and is independent of initial concentration. The mass of the pellet phase increases linearly with initial concentration. Moreover, the saturation concentration represents the critical concentration above which monomers are in equilibrium with polymers. These polymers are the putative cause of erythrocytes deformation associated with sickle cell anemia. The solubility-pH profiles of deoxy-Hb S at various temperatures, unlike those of other proteins, show no minima at the isoelectric pH but instead show a marked decrease in solubility below pH 7.0, indicating the predominance of polymerization over the expected increase in solubility. Deoxy-Hb S, within specified ranges of temperature and pH, possesses a negative temperature coefficient of solubility, a property characteristic of hydrophobic interactions. The saturation concentration is, however, temperature independent at conditions close to physiological. The enthalpy of polymerization (3.5 kcal/mol) is temperature independent from 6 degrees to 22 degrees for all pH values between 6.45 and 7.40. In the range of 22 degrees to 38 degrees, this parameter becomes less endothermic, having a value of 2.5 kcal/mol at pH 6.45 and a value of zero at pH 7.20. Such behavior of the system suggests a phase transition near 22 degreas. Within the range of conditions examined the polymerization is entropically driven.


Difference in the number of insulin binding sites between cortisol-sensitive and cortisol-resistant lymphoma P1798 cells. Cortisol-sensitive and cortisol-resistant lymphoma P1798 cells specifically bind [25I]insulin. Resistant lymphocytes bind 40% less insulin than sensitive cells. These results suggest that insulin (or insulin-like substances) may play a role in growth regulation and/or response of this tumor to glucocorticoid therapy.


Action of histamine and its receptor blockers on uterine circulation in sheep. Effects of iv and ia administration of histamine and its H1 and H2 blockers (diphenhydramine and metiamide) on systemic arterial pressure, heart rate, and uterine and iliac blood flows were investigated in unanesthetized, chronically instrumented nonpregnant ewes. Intravenous histamine produced tachycardia, hypotension, and decreased iliac and uterine blood flows. In contrast, ia injections produced a significant increase in blood flows in these vascular beds which was dose-dependent. Evidence is presented to show that some of the circulatory actions of histamine may be related to stimulation of H1 while others may be related to H2 receptors. The peripheral circulatory action produced by iv histamine is probably secondary to its effects on reducing cardiac output. The uterine and iliac vascular beds contain mostly H1 receptors since their response to histamine can be blocked almost totally by Benadryl and not by H2 antagonist metiamide.


Alpha-MSH and MIF-2 effects on serotonin levels and accumulation in various rat brain areas. Levels as well as accumulation of serotonin (5-HT) were measured in various brain regions of the rat after administration of alpha-melanocyte-stimulating hormone (MSH) and Pro-Leu-Gly-NH2 (MIF-I). The method used in determining the serotonin measured both 5-OH-tryptamine (5-HT) and 5-methoxytryptamine (5-MT). No statistically significant changes in levels or accumulation of serotonin after pargyline injection were found when unoperated control rats were treated with either MSH or MIF-I. Similar treatment of hypophysectomized rats indicated that both peptides significantly (p less than 0.05) lowered serotonin accumulation only in the area of the frontal cortex; a similar but smaller, not statistically significant, decrease was seen in the hypothalamus and hippocampus of the hypophysectomized rat. Since only hypophysectomized rats were affected, no correlation between the behavioral effects of these peptides (which has been found to occur in both unoperated and hypophysectomized rats) and the biochemical changes could be made.


Alpha-MSH and MIF-I effects on catecholamine levels and synthesis in various rat brain areas. Attempts were made to find a biochemical correlate with previously observed behavioral alterations after administration of alpha-melanocyte-stimulating hormone (MSH) and MSH release-inhibiting factor (MIF-I). Brains of intact and hypophysectomized (hypox) rats were analyzed for endogenous catecholamine levels and the disappearance rate of endogenous norepinephrine (NE) after treatment with the tyrosine hydroxylase inhibitor alpha-methyl-para-tyrosine (AMPT). The studies undertaken show the following: (1) After the injection of MSH (100 mug/kg IP daily x 3) and AMPT, samples in different groups of intact and hypox rats were taken at 0, 1, 2, 4 and 6 hrs in 7 different brain areas. In the mid-brain area for the intact group of rats, the rate of disappearance of NE was faster and for the hypox rats it was slower than the rate for control rats not treated with the peptides. NE levels in the same area at time 0 were 11 percent lower than controls in hypox rats and unchanged in unoperated animals. (2) After the injection of MIF-I (20 mg/kg IP daily x 3) in similar experiments as with MSH, a reduced rate (p less than 0.05) of NE disappearance for the first 4 hr and an increased rate (p less than 0.05) of NE disappearance for the last 2 hr of the experiments occurred for both the intact and hypox rats in the mid-brain area where endogenous NE levels were lowered by 11 and 12 percent at 0 min. In no other brain areas were alterations in NE breakdown found in both the intact and hypox rat groups. Behavioral changes have been found previously under similar experimental conditions in both intact and hypox rats. (3) Rates of dopamine disappearance in experiments similar to those described for NE disappearance indicated that in the striatal brain area no change was found in the intact rats after either MSH or MIF-I, whereas a decrease in DA disappearance was found for hypox rats during the six hour experimental period only after MSH. The results indicate that a correlation between behavioral changes, rates of disappearance and endogenous levels of NE in the mid-brain area may occur after MIF-I at the times examined but that a similar correlation for MSH did not appear likely.


Self-administration of psychomotor stimulant drugs: the effects of unlimited access. Rhesus monkeys surgically prepared with intravenous catheters were given 23 hr daily access to injection of either cocaine, d-amphetamine, 1-amphetamine, d-methamphetamine or diethylpropion on a fixed ratio 1 schedule of reinforcement for a maximum of 30 days. Responding was maintained by all these drugs but showed both day-to-day and hour-to-hour variability. The two animals self-administering 0.2 mg/kg/infusion cocaine died in less than 5 days. All 6 animals given access to 0.05 mg/kg/infusion d-amphetamine or 0.025 mg/kg/infusion d-methamphetamine also died, but tended to survive more days than animals exposed to cocaine. Three of the 5 animals whose responding was maintained by 0.5 mg/kg/infusion diethylpropion and one of the two animals whose responding was maintained by 0.05 mg/kg/infusion 1-amphetamine survived the entire 30 days despite high rates of intake. Food intake was initially decreased, but often returned to predrug levels and was not related to level of drug intake.


Rate-dependent effects of drugs: a review of the literature. It has been claimed that the effects of amphetamines on schedule-controlled behavior depend to a large extent on the rate of responding in control conditions. A review of the literature shows that there is considerable support for this hypothesis if the behavior is not suppressed by aversive procedures, is not under the control of powerful external stimuli or is not occurring very infrequently. The extension of a rate-dependency hypothesis to the effects of other drugs has less empirical support, however. It is argued that many of the procedures used for studying rate-dependent drug effects do not provide critical tests of the hypothesis. If it is to be shown unequivocally that it is rate of operant responding which determines the behavioral effects of drugs, procedures are needed in which other varibles such as reinforcement frequency are more adequately controlled.


Effect of various 6-hydroxydopamine treatments during development on growth and ingestive behavior. Destruction of catecholamine-containing fibers in brain at 5 days of age with intracisternal injection of 6-hydroxydopamine reduced body growth, intake of a sucrose solution, and acquisition of an active avoidance response. Further characterization of behavioral deficits indicated that treated animals also showed reduced ingestion of saline solution when injected with desoxycorticosterone and a decreased eating response to insulin. In addition, all of these deficits produced by catecholamine depletion with 6-hydroxydopamine were observed in rats in which brain dopamine was preferentially reduced but not in rats having preferential destruction of noradrenergic fibers, suggesting that dopamine depletion amounts for the observed alterations in developing animals. Although animals treated with 6-hydroxydopamine at 14 days showed reduced intake of a sucrose solution, they did not have reduced growth. Since early malnourishment reduced growth, it seems possible that the reduced growth observed after destruction of dopaminergeic fibers may be related to an acute reduction of food intake which is perpetuated by persistent deficits in ingestive behavior. Evidence implicating malnourishment in other deficits produced by 6-hydroxydopamine could not be obtained.


Schedule-induced oral self administration of etonitazene. Rats were induced to drink either a saline-etonitazene solution or a saline solution with a schedule-induced polydipsia paradigm. When water was freely available, the rats continued to drink the saline solution or the saline-etonitazene solution, rather than the water. When the locations of the solutions were switched, the rats that were drinking saline switched to water (drank at the usual location), but the rats that were drinking saline-etonitazene continued to drink the saline-etonitazene solution (drank from the bottle at the other location). Naloxone administration temporarily eliminated the drinking of saline-etonitazene solution, but not that of saline solution.


Enzyme activity in sleep and sleep deprivation. Liver tyrosine transaminase activity is low during the day when the rats are mostly asleep and high during the night when they are awake. When wakefulness was imposed for 8 hr during daylight on the day of the experiment and the rats were allowed to sleep for the following 3 hr during darkness, the tyrosine transaminase activity became high during the day and low at night. That this reversal in enzyme activity is not mediated by the pituitary-adrenal axis is demonstrated by the fact that in adrenalectomized rats tyrosine transaminase activity increased during the day in the sleep deprived rats. However, in these rats the enzyme activity did not become low in the sleep-deprived-sleeping condition. Changes in tryptophan pyrrolase activity during sleep deprivation were demonstrated to be mediated by the pituitary-adrenal axis.


The genetics of the mimetic butterfly Hypolimnas bolina (L.). Hypolimnas bolina is a Nymphalid butterfly having a west to east distribution from Madagascar to Easter Island, and a north to south one from Japan to Australasia. It is highly migratory in some areas. In much of the western part of its range the female is both monomorphic and a mimic of Euploea. Further east it is frequently polymorphic with the majority of the forms being non-mimetic. The polymorphism is sex-limited to the female and controlled by two unlinked loci, one with two allelomorphs, E and e, determining the extent of the dark pigmentation, the other with three allelomorphs, P, Pn and p, determining the presence and distribution of orange-brown. Only butterflies of the genotypes EEpp and to a lesser extent Eepp are satisfactory Batesian mimics of their Euploea models. The details of the mimetic pattern are under multifactorial control, following those of their local model, as is much of the variation within the non-mimetic forms, particularly with regard to the distribution of white and blue scaling.


Terrestrial vertebrates of the New Hebrides: origin and distribution. The known terrestrial vertebrate fauna of the New Hebrides consists of 16 species of mammals (excluding feral domestic stock), 61 species of resident land- and freshwater birds, 20 species of reptiles and one amphibian. Of these, three, five, four and one species respectively have apparently been introduced by man. The non-introduced fauna is clearly Indo-Australian in origin, but some species have an exclusively Pacific island distribution and others (two bats, seven birds, and four lizards) are endemic. On the six islands visited 95 out of the possible 98 vertebrate species occur. Santo, the largest and most northerly island, supports the richest fauna. The comparative impoverishment of more southerly islands is not directly attributable to the progressive increase in isolation and distance from presumptive source area, nor to decrease in island area or maximum height.


5-Aminolaevulinic acid dehydratase: structure, function, and mechanism. delta-Aminolaevulinic acid dehydratase catalyses the synthesis of porphobilinogen. The enzyme has a molecular mass of 285000 and is composed of eight similar subunits of molecular mass 35000. The N-terminal amino acid is acylated, and the number of peptides found on tryptic digestion equals the number of lysine and arginine residues per mass of 35000. The eight subunits are apparently arranged at the corners of a cube and therefore have dihedral (D4) symmetry. The bovine liver enzyme which has been cystallized contains 4--6 atoms of zinc per mole of enzyme. The apo-enzyme obtained on prolonged hydrolysis can be reactivated by the addition of zinc or cadmium ions. The dialysed enzyme must be first treated with dithiothreitol. There are two very active SH groups in a total of 6--7-SH groups per subunit. The substrate forms a Schiff base with the epsilon-amino group of a lysine residue. Reduction of the Schiff base with NaBH4 should reveal the number of active sites per mole of enzyme. It appears that only four of the eight subunits form a Schiff base with the substrate indicating that the enzyme exhibits the phenomenon of either half-site reactivity or negative cooperativity. The enzyme appears to have a strong subunit-subunit interaction for an immobilized preparation remained stable for at least a month. An immobilized enzyme preparation was treated in a manner so that it dissociated into tetramers. Both the eluate and protein still attached to the Sepharose on a column were enzymically active. The bound enzyme could not reassociate under assay conditions but still contained about 50% of the original enzyme activity. It would seem that the enzyme is active when composed with less than eight subunits.


Mechanism and stereochemistry of enzymic reactions involved in porphyrin biosynthesis. 5-Aminolaevulinate synthetase cataylses the condensation of glycine and succinyl-CoA to give 5-aminolaevulinic acid. At least two broad pathways may be considered for the initial C--C bond forming step in the reaction. In pathway A the Schiff base of glycine and enzyme bound pyridoxal phosphate (a) undergoes decarboxylation to give the carbanion (b) which then condenses with succinyl-CoA with the retention of both the original C2 hydrogen atoms of glycine. In pathway B, loss of a C2 hydrogen atom gives another type of carbanion (c) that reacts with succinyl-CoA. Evidence has been presented to show that the initial C--C bond forming event occurs via pathway B which involves the removal of the pro R hydrogen atom of glycine. Subsequent mechanistic and stereochemical events occurring at the carbon atom destined to become C5 of 5-aminolaevulinate have also been delineated.(Carticle) Several mechanistic alternatices for the formation of the two vinyl groups of haem from the propionate residues of the precursor, coproporphyrinogen III, have been examined. (see article). It is shown that during the biosynthesis both the hydrogen atoms resident at the alpha positions of the propionate side chains remain undisturbed thus eliminating mechanisms which predict the involvement of acrylic acid intermediates. Biosynthetic experiments performed with precursors containing stereospecific labels have shown that the two vinyl groups of haem are formed through the loss of pro S hydrogen atoms from the beta-positions of the propionate side chains. In the light of these results, three related mechanisms for the conversion, propionate leads to vinyl, have been considered. In order to study the mechanism of porphyrinogen carboxy-lyase reaction, stereo-specifically deuterated, tritiated-succinate was incorporated into the acetate residues of uroporphyrinogen III which on decarboxylation generated asymmetric methyl groups in coproporphyrinogen III and then in haem. Degradation of the latter yielded chiral acetate deriving from C and D rings of haem. Configurational analysis of this derivate acetate shows that the carboxy-lyase reaction proceeds with a retention of configuration.


Biosynthesis of uroporphyrinogens from porphobilinogen: mechanism and the nature of the process. The enzymic self-polymerization of prophobilinogen gives rise to the cyclic tetrapyrroles uroporphyrinogen III and uroporphyrinogen I. The former is the precursor of all the natural porphyrins and chlorins. The formation of uroporphyrinogen III is catalysed by a dual enzymic system, porphobilinogen deaminase and uroporphyrinogen III cosynthase. Deaminase polymerizes four porphobilinogen units on the enzymic surface, without liberation of free intermediates into the reaction medium, and forms uroporphyrinogen I. Cosynthase enters into association with the deaminase, and acts as a 'specifier protein' of the latter, changing the mode of porphobilinogen condensation on the enzymic surface. The association is independent of the presence of substrate. While deaminase catalyses the head-to-tail condensation of the porphobilinogen units, the association deaminase-cosynthase catalyses the head-to-head condensation of the same units. As a result different enzyme-bound dipyrrylmethanes are formed form the beginning of the process, and this can be demonstrated by using synthetic dipyrrylmethanes and tripyrranes.


Biosynthesis of porphyrins and corrins.

Biosynthesis of porphyrins and corrins. Haem, chlorophyll and vitamin B12 are all derived ultimately from four molecules of the pyrrole porphobilinogen (PBG) and the initial enzyme catalysed condensation of PBG leads to the unsymmetrical type III isomer of uroporphyrinogen. On the basis of straightforward chemical considerations the type I isomer should be formed and so the porphyrinogen-forming enzymes of all living systems must catalyse a highly specific rearrangement process. The nature and chemical mechanism of this rearrangement poses one of the most fascinating problems in the porphyrin field and so it is not surprising that over 20 hypothetical schemes have been proposed to account for it. Analysis of the problem suggested that the incorporation of doubly 13C-labelled precursors into the rearranged macrocyclic rings would give valuable new information on the nature of the rearrangement process. In this approach the meso=bridge atoms are of crucial importance, and several unambiguous syntheses of 13C-labelled pyrroles and porphyrins were developed to allow rigorous n.m.r. assignments to be made, and also to provide substrates for enzymic experiments. Studies carried out with enzymes from both avian blood and from Euglena gracilis have revealed the precise nature of the assembly of four PBG molecules into the type-III macrocycle: it is the same in both systems despite their vastly different evolutionary development. Complementary studies are in progress in order to determine the intermediates involved in the conversion of PBG into uroporphyrinogen III. The synthesis of amino methyl pyrromethanes and their interaction in the presence of PBG with the appropriate enzyme systems are described. It is important for the work to be able to separate not only isomeric pyrromethanes but also the four isomeric coproporphyrins. Powerful methods are described which make use of high pressure liquid chromatography for both types of separation process. Once uroporhyrinogen III has been built enzymically, there is a stepwise enzymic decarboxylation of the four acetic acid residues. A heptacarboxylic porphyrin shown to be a type-III porphyrin is isolated from the action of avian blood enzymes on porphobilinogen. Spectroscopic studies with 13C-labelling limit the possible structures to two and total synthesis of these substances shows that the natural product carries its methyl group on ring D. An isomeric heptacarboxylic porphyrin having its methyl group on ring C is of particular interest in relation to the biosynthesis of vitamin B12. This substance is synthesized together with uroporphyrin III, 14C-labelled specifically in ring C. This latter product is used to settle one of the key questions concerning nature's route to vitamin B12 - that is, does the corrin macrocycle arise from uroporphyrinogen III? Incorporation studies and specific degradations prove specific incorporation of uroporphyrinogen III into cobyrinic acid, which is the known precursor of vitamin B12.


Synthesis of probable and improbable precursors for porphyrin biosynthesis. Insights into details of the biomechanism by which porphobilinogen (1) cyclotetramerizes to uroporphyrinogen III (2) as well as promising synthetic applications are provided by investigation of this reaction in vitro. The cyclotetramerization of newly prepared norporphobilinogen (5) proved to be extemely specific due to strong conformation control. Advantage was taken of this finding by preparing a N,N,N,N-tetramethyl-porphyrinogen (13a) for the first time. Protected derivatives of the linear tetramer of porphobilinogen (20c) which is regarded as an intermediate of the cyclotetramerization were gained by total synthesis and their transformations investigated.


Macrocyclic intermediates in the biosynthesis of porphyrins. The hepta-, hexa- and penta-carboxylic porphyrins found in the faeces of rats poisoned with hexachlorobenzene have been separated by high-pressure liquid chromatography and characterized largely by spectroscopie methods. Their structures were confirmed by total synthesis, as part of a programme in which eleven of the fourteen hepta-, hexa- and penta-carboxylic porphyrins derived from uroporphyrin III have now been synthesized as their methyl esters. The four isomeric heptacarboxylic and three of the pentacarboxylic porphyrinogens have been incubated with haemolysates of chicken erythrocytes, and they are all converted into protoporphyrin IX but at different rates. On the basis of this and other evidence we conclude that the decarboxylation of uroporphyrinogen III to coproporphyrinogen III is a stepwise process taking place by a preferred pathway (both in normal and abnormal metabolism); the acetic acid groups are decarboxylated in a sequential clockwise fashion starting with that on the D ring and followed by those on the A, B and C rings. In the poisoned rats the uroporphyrinogen decarboxylase enzyme (or group of enzymes) is probably partially inhibited and the pentacarboxylic porphyrinogen with an acetic acid group on ring C accumulates. The latter is then transformed by a side pathway into dehydroisocoproporphyrinogen and thence into dehydroisocoproporphyrin and its congeners.


Neovitamin B12 (cyano-13-epicobalamin).

Neovitamin B12 (cyano-13-epicobalamin). Beta-Epimerization in the corrinoid system has recently emerged as a complicating factor in the latter stages of the total synthesis of vitamin B12 (Eschenmoser 1971; Woodward 1973). It has also found some application in biosynthetic studies on the origin of the methyl groups in ring C (Scott, Townsend & Cushley 1973; Scott, this Discussion p. 303). This paper sets out to review briefly the beta-epimerization of corrinoid polyamides, with particular reference to our work on the neo-series which provided the first established example of this phenomenon.


The biosynthesis of vitamin B12.

The biosynthesis of vitamin B12. The use of 13C-Fourier transform nuclear magnetic resonance (F.t.-n.m.r.) has led to the observation that while 8 molecules of [2-13C]ALA are incorporated into vitamin B12 in P. shermanii, [5-13C]ALA labels only seven of the carbon atoms of cyanocobalamin, i.e. one of the amino methyl groups of ALA is "lost" in the process. It has also been confirmed that seven of the methyl groups of B12 are derived from 13CH3-enriched methionine and further that the chirality of the gemdimethyl grouping at C12 labelled with [13CH3]methionine is R. A soluble enzyme mixture from the 37000 or 100000 g supernatant of disrupted cells of P. shermanii converts both 14 C-labelled ALA and [14C]uro'gen III to cobyrinic acid, the simplest corrinoid material on the pathway to vitamin B12 and the coenzyme, in presence of NADPH, Co2+, Mg2+, S-adenosyl-methionine and glutathione. Multiply-labelled uro'gens (13C, 14C and 3H) have been used to show that incorporation takes place without randomization. A sequence for corrin synthesis from uro'gen III is presented.


Synthesis of corrins and related macrocycles based on pyrrolic intermediates. Intermediate in structure between porphyrins and corrins are the corroles and 1-methyltetradehydrocorrins. These ring systems, like the porphyrins, can be obtained by cyclization of linear tetrapyrrolic compounds, reactions which have been shown to proceed by orbital symmetry-allowed electrocyclic processes, and examples will be quoted. Thermolysis of nickel 1-methyltetradehydrocorrins causes a migration of the methyl group whereas similar treatment of nickel 1,19-dimethyltetradehydrocorrin salts yields porphyrin derivatives; the mechanisms of these transformations have been elucidated. Stepwise hydrogenation of metal tetradehydrocorrin salts (10 double bonds) yields a series of macrocycles containing 9, 8, 7, 6 and 5 double bonds and conditions necessary to obtain corrins have been established.


Chemical behavior of dicyanocob(III)yrinic acid heptamethyl ester and cob(I)yrinic acid heptamethyl ester in some preparative experiments. Preparations of C10 acetate, trifluoroacetate, and chloro derivatives of dicyanocobyrinic acid heptamethyl ester ('cobester') are described. The nature and properties of intermediates in the synthesis of the 10-chloro derivative are discussed, and the electronic absorption spectra of the products are presented.


Chemical reactivities of tetrapyrrole pigments: a comparison of experimentalbehaviour with the results of s.c.f.-pi-m.o. calculations. Porphyrins are highly sigma-electron donating bases and very weak pi-acids. Hence they increase the electron density  on central metal ions, e.g. iron, which leads to the specific reactivity of haem cytochromes, haemoglobin and oxidizing enzymes. The macrocyclic chlorin ligand behaves similarly but to a lesser degree which explains the comparably low oxidation potential of chlorophyll. Phlorins, oxophlorins, oxa- and aza-orphyrins, tetradehydrocorrins, corrins and biliverdins all produce metal complexes which have a similar geometry to that of metalloporphyrins, but their reactivity patterns are different. In contrast to the metalloporphyrins which undergo many fully reversible reactions, these compounds tend to irreversible addition and cleavage reactions. The tetrapyrrole ligands are stronger pi-acids than porphyrins. Results of some recent experimental work and pi-electron s.c.f. calculations are presented in support of these generalizations.


The structures of some cobalamins in solution. Nuclear magnetic resonance spectroscopy has been used to examine the conformations of cobalamins in solution. The perturbation of the resonances in the n.m.r. spectra by lanthanide probes provided particularly valuable information. Except for minor details the conformations are the same as those in the crystalline state. The temperature dependence of the conformation has been reassessed.


Control of 5-aminolaevulinate synthetase activity in Rhodopseudomonas spheroides. Rhodopseudomonas spheroides can grow in a defined medium with either light or oxygen as an energy source. Cells grown anaerobically or at very low oxygen tensions are rich in the photosynthetic pigment bacteriochlorophyll, whereas this pigment is virtually absent in cells grown under high oxygen tensions. Aminolaevulinate synthetase, the first enzyme on the pathway to bacteriochlorophyll, appears to play an important role in the control of bacteriochlorophyll synthesis. Thus, the enzyme has a high activity in extracts of pigmented cells and a low activity in extracts of non-pigmented cells. Further, oxygenation of a pigmented culture causes immediate cessation of pigment synthesis and produces a rapid fall in the activity of aminolaevulinate synthetase. This loss of activity appears to be due to the loss of an endogenous activator of the enzyme. Thus, pigmented cells contain cystine trisulphide, which at muM concentrations is an activator of aminolaevulinate synthetase, while oxygenation causes a rapid fall in the cellular content of this trisulphide. Cystathionase (EC 4.2.1.15) extracted from pigmented cells can catalyse the formation of cystine trisulphide from cystine, while rhodanese (EC 2.8.1.1) extracted from the same cells can catalyse the degradation of cystine trisulphide in the presence of sulphite to form cystine and thiosulphate. It is proposed that the cellular content of cystine trisulphide is controlled by changes in the levels of substrates for cystathionase and possibly rhodanese rather than changes in the amounts of these enzymes. Cystine trisulphide controls the activity of aminolaevulinate synthetase by converting a low-activity form of the enzyme (b-form) into a high-activity form (a-form). The fall in aminolaevulinate synthetase activity on oxygenation appears to be the result of cessation of conversion of b-form into a-form, along with a conversion of a-form into b-form. Factors affecting the equilibrium between the forms and the possible mechanisms for their interconversion are discussed.


The structural subunit of glucose-6-phosphate dehydrogenase (baker's yeast). The subunit molecular weight of glucose-6-phosphate dehydrogenase (G6PD) from baker's yeast has been evaluated. The subunit molecular weight value is shown to be 25,500 daltons by analytical ultracentrifugation, SDS-polyacrylamide gel electrophoresis, and the number of peptides produced by CNBr cleavage. The number of NADP binding sites was determined to be one per 25,500 dalton unit.


Study of cystinaminopeptidase heterogeneity in animal sera by the isoelectric focusing method. Study of the quantitative distribution of cystinaminopeptidase activity in the serum of pregnant and control animals (cow, sheep and rat) by the isoelectric focusing method showed heterogeneity of the cystinaminopeptidase activity of the animals' serum enzymatic system, which was well pronounced in the cow and rat and less pronounced in the sheep. The authors assume from their results that the principal difference between the pregnant and control animals is not the total increase in the level of activity of the enzyme in question, but the shift in its incidence, or the increase in activity at a given pH. It is possible that pregnancy, in man and animals, produces in the serum cystinaminopeptidase system (which is evidently heterogeneous even under normal, physiological conditions) given changes, i.e. the formation of new fractions with a different pI from the controls; other fractions disappear, or their activity diminishes.


Thiopental anaesthesia and the acid-base balance in the blood of experimental dogs. An analysis of basic parameters representative of the acid-base balance was made in arterial blood samples from 140 clinically healthy dogs, under a general intravenous Thiopental anaesthesia. The following mean values +/- S.E.M. were obtained: pH = 7.33 +/- 0.01; pCO2 = 47.16 +/- 0.95; base excess = -2.12 +/- 0.27; buffer base = 46.63 +/- 0.37. The results showed a prevalent trend of lower values of pH, base excess and buffer base and higher values of pCO2 than those found commonly in human clinical practice. Special attention was paid to the respiratory component of the acid-base balance (ABB) revealing certain undesirable side effect of Thiopental anaesthesia.


Fast neutron and x-ray induced single strand DNA breaks in cultured mammalian cells. The relative biologic effectiveness (RBE) of fast neutrons in the production of single strand DNA breaks is 1.6 as compared to that of 250 kVp x rays. Monolayers of L-929 cells were treated with dinitrophenol during irradiation to prevent the DNA strands from rejoining; the extent of DNA damage was measured by the alkaline sucrose sedimentation method. The RBE for DNA damage is essentially the same as the RBE measured by cell survival methods.


Inhibition of prostaglandin biosynthesis by sulphasalazine and its metabolites. Sulphasalazine (SZ) inhibits prostaglandin (PG) biosynthesis in vitro with a potency comparable to that of aceylsalicylate. The metabolites of SZ, sulphapyridine and 5-aminosalicylic acid, were of considerably lower potency as inhibitors of PG biosynthesis in the synthetase preparations used. Th inhibition of prostaglandin production by SZ could at least partly account for the clinical utility of sulphasalazine in ulcerative colitis. Sulphapyridine may help to maintain inhibitory concentrations of SZ by restraining bacterial breakdown of the active drug.


Partial characterization of prostaglandin synthetase in the reproductive tract of the male house cricket, Acheta domesticus. An active prostaglandin (PG) synthetase was found in the 12100 g pellet of reproductive tract homogenates of the male house cricket, Acheta domesticus. Comparatively, the 12100 g supernatant and the microsomal fractions were inactive. The PG synthetase in the pellet fraction was characterized in terms of cofactor, temperature, pH, and incubation time requirements. Indomethacin, a known inhibitor of mammalian PG synthetase, was not inhibitory to the cricket synthetase. The procedure and findings are relevant to PG synthetase studies of any organism or tissue.


Hydroxyzine hydrochloride: possible adverse cardiac interactions. Hydroxyzine hydrochloride may produce abnormal ventricular repolarization when given in substratial doses or to susceptible individuals. Phenothiazines, such as thioridazine, tricyclic antidepressants, or antiparkinson drugs, any of which may be given concurrently to psychiatric patients, may augment this effect as well as atropine, quinidine or procainamide. Such EKG abnormalities may increase the likelihood of dysrhythmias and sudden death.


Assessment of antipsychotic activity of an unique agent: SU-23397. SU-23397 is a unique new hybrid molecule, the animal profile being characteristic of neuroleptic activity. Although the trial was uncontrolled, there appears to be no doubt that SU-23397 exerts antipsychotic activity between 20 mg and 250 mg daily in severely ill schizophrenic patients. Seven of the ten subjects required at least transient antiparkinson medication. Two patients demonstrated premature ventricular contractions. One patient had infrequent PVCs at baseline which increased in frequency with rising dosage. The other patient developed frequent premature ventricular contractions only after active and medication was initiated and was subsequently withdrawn from the study.


The effect of various chlorpromazine derivatives on the apomorphine-elicited inhibition of synaptosomal tyrosine hydroxylase activity. The effects of chlorpromazine and of some metabolites of chlorpromazine on the apomorphine-elicited inhibition of synaptosomal tyrosine hydroxylase activity were investigated. Chlorpromazine, nor1-chlorpromazine and 7-hydroxychlorpromazine reverse the apomorphine-elicited inhibition of tyrosine hydroxylase activity while nor1-chlorpromazine sulfoxide and nor2-chlorpromazine sulfoxide have no effect on this inhibition. 6-Hydroxychlorpromazine and promethazine also reverse the enzyme inhibition by apomorphine but are less potent than chlorpromazine or 7-hydroxychlorpromazine. These results show that chlorpromazine and its metabolites with antipsychotic activity are more effective in reversing the apomorphine-elicited inhibition of tyrosine hydroxylase than those metabolites which are devoid of antipsychotic activity.


Effects of benzodiazepines on the binding of tryptophan in serum. Consequences on 5-hydroxyindoles concentrations in the rat brain. Benzodiazepines (diazepam, oxazepam, chlordiazepoxide) inhibited competitively the binding of tryptophan onto rat serum albumin. As a result, in vivo treatment with one of these compounds (chlordiazepoxide for instance) induced a significant increase in the concentration of free tryptophan in serum. These observations suggest that the high levels of both 5-hydroxyindoles and tryptophan which occurred in the rat brain after any benzodiazepine administration could be at least partly the consequence of its effect on tryptophan binding in blood.


The search for the dopamine receptor: tribulations. In an attempt to identify specific binding to dopamine receptors the binding of 3H-pimozide to preparations of brain and to an artificial cellulose membrane was examined. Binding occurred rapidly, was pH and temperature dependent, and was displaceable by other neuroleptics. Displaceable binding was saturable at 5 X 10(-8) M pimozide. A weak correlation between IC50's for displacement of binding by drugs and their clinical potencies was observed. Displaceable binding of 3H-pimozide in different brain areas did not correlate with dopamine levels. The similarity of binding properties to brain and to artificial membrane suggests that these effects are a function of the physical-chemical properties of these drugs, and that these properties may be related to their clinical effect.


Functional heterogeneity within neurotransmitter systems. This paper reviews experiments that have revealed distinct differences between the dorsal and median raphe nuclei in the rat midbrain. The raphe nuclei appear to be hetrogeneous with respect to their anatomical projections to the forebrain, their relevance to specific behaviors, and their pharmacological responses. Startle response measures are useful indicators of the functional state of serotonergic system originating in the median raphe. As a way to study individual cells within the various raphe nuclei, microspectroflurimetric techniques are promising.


Benzodiazepines and reproduction of swiss-webster mice. Chronic dietary administration of 6 different benzodiazepine tranquilizers (chlordiazepoxide, diazepam, oxazepam, prazepam, flurazepam, and nitrazepam) to breeding pairs of Swiss-Webster mice resulted in alterations of the normal patterns of reproductive behavior and fetal growth. Significant decreases in mating performance were seen among mice given diets containing 0.15% chlordiazepoxide, 0.05% diazepam, 0.05 and 0.15% oxazepam, 0.02 and 0.10% prazepam, 0.10% flurazepam, and 0.025% nitrazepam. Offspring in all drug treatments showed significantly depressed body weights at birth.


In vitro and in vivo studies of (1-sarcosine, 8-threonine) angiotensin II. The capacity of (1-Sarcosine, 8-Threonine) angiotensin II to block the contractile and pressor effects of exogenous and endogenous angiotensin II was examined. In isolated rabbit aorta, the pA2 value (from pA2 plots) for the analog was 8.75 +/- 0.11. Both the maximum response and the slope of the dose-response curve to angiotensin II were unchanged by the analog. In ganglion-blocked vagotomized rats, infusion of the analog produced a dose-dependent blockage of the angiotensin II pressor effect. In these rats, the analog displayed less agonistic activity than that of (1-Sarcosine, 8-Isoleucine) and (1-Sarcosine, 8-Alanine) angiotensin II. In two-kidney hypertensive rats, the angiotensin II antagonist significantly reduced the arterial blood pressure. The results indicate that (1-Sar, 8-Thr) angiotensin II is a potent antagonist of angiotensin II with less inherent agonistic activity than previously reported analogs.


The effect of mercuric chloride intoxication on urinary psi-glutamyl transpeptidase excretion in the sheep. The activity of the enzyme psi-glutamyl transpeptidase (psi-GT) was measured in the urine of sheep. In clinically normal animals the mean value was 6-3+/-0-6 mU/ml. In sheep with  kidney damage induced by the administration of mercuric chloride there were marked increases in urinary concentrations of psi-GT, in some cases values in excess of 1000 mU/ml were recorded. This enzyme may be of value in the diagnosis of certain forms of renal disease.


Nucleotide pyrophosphatase and phosphodiesterase I. Demonstration of activity in normal serum, and an increase in cholestatic liver disease. Nucleotide pyrophosphatase activity with uridine diphosphoglucose and dephospho-CoA as substrates was demonstrated in normal human serum. The enzyme has a pH-optimum of about 9.6 and is inhibited by EDTA. Phosphodiesterase I (hydrolysis of thymidine-5'-monophospho-p-nitrophenylester) was also found in normal human serum, with a pH-optimum of about 9.8 and a Km of 0.20-0.25 mM. Probably both activities should be attributed to one enzyme. Different isoenzymes may exist, however. The activity of nucleotide pyrophosphatase/phosphodiesterase I in normal serum in many respects resembles an enzyme previously isolated from liver plasma membranes. Phosphodiesterase I activity was increased in normal pregnancy, in primary biliary cirrhosis, and in patients with bone lesions, but not in acute viral hepatitis or active chronic hepatitis. In primary biliary cirrhosis, the activity of phosphodiesterase I paralleled an increase of alkaline phosphatases.


[The value of renin determination in the diagnosis of hypertension]. Primary aldosteronism and renovascular hypertension are two different diseases in which renin determinations are necessary for establishment of diagnosis or therapeutic procedure. Low renin values which are not stimulated by acute stimuli combined with elevated plasma aldosterone concentrations confirm the diagnosis of primary aldosteronism. When in a patient with proven renal artery stenosis a significant difference in renal venous renin activity is observed between the two kidneys, a connection between hypertension and renal artery stenosis is likely when in addition the renin secretion of the unaffected kidney is suppressed. A favourable outcome for surgery can be predicted when the individual clinical picture in such a case is also considered. A similar view also holds for the connection between hypertension and unilateral small kidney not due to renal artery stenosis. In essential hypertension the plasma renin level makes it possible to a certain extent to predict whether a patient will benefit from diuretics or from beta-blocking agents. Despite this experience, however, renin determinations are not indicated in every case of essential hypertension. It has not been proven that the prognosis of this disease is improved by renin oriented monotherapy rather than by effective treatment with other antihypertensive agents.


Alpha-adrenergic receptor identification by (3H)dihydroergocryptine binding. A radioactively labeled alpha-adrenergic antagonist, [3H]dihydroergocryptine, binds specifically to a site on rabbit uterine membranes. Binding is rapid, reaching equilibrium in less than 17 minutes at 25 degrees C. Adrenergic agonists compete for this binding site with an order of affinities identical to the pharmacological potency order of these agents as alpha-adrenergic agonists (epinephrine greater than norepinephrine greater than isoprotereonl). The (-) stereoisomers of epinephrine and norepinephrine are 30 times more potent in competing for the site than the corresponding (+) stereoisomers. alpha-Adrenergic antagonists, such as phentolamine and phenoxybenzamine, potently compete for the binding sites while the beta-adrenergic antagonist propranolol does not. Structural analogs of catecholamines that are devoid of alpha-adrenergic physiological activity do not compete for [3H]dihydroergocryptine binding sites. These data suggest that alpha-adrenergic receptors can be directly identified and studied by [3H]dihydroergocryptine binding.


Aspartate: distinct receptors on Aplysia neurons. Aplysia neurons have specific aspartate receptors that are distinct from those to glutamate. In some cells, asparate selectively increases the membrane permeability to chloride, giving rise to a hyperpolarization, while on other cells it increases the permeability to sodium, causing a depolarization. There are also specific receptors for L-glutamate which mediate sodium, chloride, or potassium conductance increases, and another class of receptors activated by both glutamate and aspartate.


Reduction in myocardial infarct size: prevention of heart cell death. The course of myocardial necrosis, the clinical syndrome, and methods of treatment are presented. Heart cell death may be prevented by maintaining the balance between myocardial oxygen and energy supply and consumption. New technics of improving this balance by reducing myocardial energy demand, altering metabolism, increasing myocardial substrate supply, and protecting cellular integrity are discussed.


Hypo-acidity of gastric juice in chronic gastric ulceration caused by neutralisation. Samples of gastric juice were aspirated every 15 minutes from 54 normal subjects and 31 patients with chronic gastric ulcers during a maximal histamine infusion test. The known tendency of patients with gastric ulcers to secrete a less acid gastric juice than that of normal subjects was confirmed. However, the hypo-acidity was related to the extent by which the total ionic concentration was less than the isotonic value of 328 mEq/l. On the assumption that such hypo-acidity was produced by the neutralisation of hydrogen ions by bicarbonate ions refluxing into the stomach from the duodenum, the data were corrected and resulted in a normal estimate of the hydrogen ion concentration in the gastric ulcer group. Independent corrections, according to the sodium content of refluxed duodenal juice, yielded similar results for the volume of gastric juice aspirated. It is concluded that while back-diffusion can explain the hypo-acidity of gastric juice in patients with gastric ulcers, duodenal reflux can explain both the hypo-acidity and the hypotonicity, and is therefore more likely to be the correct explanation.


Antihypertensive therapy with timolol and alpha-methyldopa. A double-blind trial in patients with moderately severe hypertension. After 24 moderately severe hypertensive patients had been treated for 4 weeks with a placebo for timolol, alpha-methyldopa was added and titrated until control of the blood pressure or a total daily dose of 2 500 mg was achieved. At the 9th week, the dose of alpha-methyldopa was halved and either timolol or its placebo was titrated in double-blind fashion. Titration over a period of 4 weeks was followed by a further 5 weeks of stabilisation. In 22 patients whose responses were accepted for analysis, alpha-methyldopa caused a significant lowering of blood pressure, with a greater reduction in the upright posture and a reduction in pulse rate. The addition of timolol caused a highly significant further reduction in pulse rate and a significant reduction in blood pressure in 8 of 10 patients. Apart from a statistically significant increase in serum urea and creatinine with, however, retention of normal renal function, no other side-effects were attributable to timolol.


Iatrogenic cryptorchidism resulting from hernia repair. Nine children have been examined for iatrogenic cryptorchidism during a four year period. Wound infection and testicular retractility appear to be factors predisposing to this complication. Routine testicular palpation for position at the completion of hernia repair and the use of orchidopexy in selected patients should aid in the prevention of this problem.


The effect of antihistamines on experimental posttraumatic edema of the spinal cord. The present experiments were designed to test the effect of antihistamines on the formation of post-traumatic edema of the spinal cord. Ten rhesus monkeys received 600 gm cm injuries to the T10 level of the spinal cord. Five animals received antihistamine treatment and five animals acted as untreated controls. Posttraumatic edema was estimated using radio-active tagged serum albumin. A significant increase in radioactivity of the injured segment was demonstrated in both groups when compared to noninjured issue, but no difference was demonstrated in the radioactivity of the injured segment in the treated versus the nontreated group.


Chemical studies of marine invertebrates. XVI. Structure and absolute configuration of lobosterol, a novel polyoxygenated sterol from the alcyonacean Lobophytum pauciflorum (clelenterata, octocorallia). Lobosterol [(24S)-24-methylcholestane-3beta,4beta,5beta,25-tetrol-6-one 25 monoacetate] has been isolated from the Alcyonacean Lobophytum pauciflorum. The structural elucidation of this novel polyoxygenated sterol was achieved by chemical and spectroscopic evidence, and by X-ray diffraction analysis.


Irreversible protein binding of norethisterone (norethindrone) epoxide. 14,15-3H-Norethisterone-4 beta, 5 beta-epoxide, a metabolite of norethisterone, was incubated with several proteins and nucleic acids. After 30 min incubation 0.19 nmol of the epoxide were irreversibly bound per mg albumin which contains free sulfhydryl groups; proteins without SH-groups, such as concanavalin A, gamma-globulin, DNA and RNA, did not irreversibly bind norethisterone epoxide. A superoxide (O2) generating enzyme system comprised of xanthine oxidase and hypoxanthine was capable of catalyzing the irreversible binding of the parent compound, norethisterone, to albumin, indicating that an oxidation product was formed which reacted with the protein. When norethisterone epoxide was incubated for 60 min with hepatic microsomes of rats in absence of NADPH, about 2.0 nmol of the epoxide were irreversibly incorporated per mg microsomal protein. This binding was increased to 5.2 nmol by addition of a NADPH regenerating system. Addition of glutathione and cytosol decreased only the NADPH-dependent protein binding; phenobarbital pretreatment of rats induced this NADPH-dependent binding of norethisterone epoxide to microsomal protein by a factor of 2. In presence of NADPH, binding of the epoxide to microsomal protein depended on substrate concentration used. The results indicate that norethisterone epoxide is able to chemically react with proteins. In addition, hepatic microsomal enzymes convert the epoxide to another metabolite which also can react with proteins.


Hydroxyapatite - a reagent for the separation of free and antibody-bound steroid during the radioimmunoassay. The use of hydroxyapatite to absorb antibody-bound steroid and thus separate free and antibody-bound steroid during radioimmunoassay has been examined using three steroid antisera (to testosterone, to 17-hydroxyprogesterone and to estradiol-17beta). For all three antisera studied the separation was shown to be independent of length of time in contact with hydroxyapatite (up to 1h); temperature variations from 4 degrees -37 degrees and pH over the range 4.9-8.0. The presence of protein affected the absorption of antibody-bound steroid but this effect could be overcome by the addition of increasing amounts of hydroxyapatite. Further increase in the amount of hydroxyapatite added had no effect on the separation of free and bound steroid. Sodium phosphate buffers of molarity greater than 0.01M eluted antibody-bount steroid from hydroxyapatite, but Tris-HC1 buffers up to molarities of 0.1 M had no effect. Hydroxyapatite when used as a dry powder had the same effects as suspensions. No effect on the cross-reactivities of the antisera used could be demonstrated when hydroxyapatite was used and plasma testosterone assays on 22 plasma samples using hydroxyapatite gave essentially the same results as assays on the plasma using a coated-tube assay. Hydroxyapatite can also be successfully pumped along small bore plastic tubing without settling and can thus be used in automated immunoassay systems.


Influence of adrenergic receptor blockade on circulatory and metabolic effects of disordered neurotransmitter function in stroke patients. Cerebral hemispheric blood flow and metabolism were measured before and after therapy with intracarotid infusion of combined PBZ and PPL in 15 patients with recent cerebral infarction. HBF was unaltered despite decrease in cerebral perfusion pressure. Cerebral hemispheric oxygen comsumption and carbon dioxide production decreased while cerebral hemispheric lactate production increased. Biphasic cerebral uptake of tyrosine was observed during and immediately after PBZ and PPL infusion. CSF HVA increased, indicating altered DA turnover. CSF 5HIAA levels also increased, suggesting altered 5HT turnover after PBZ and PPL. Release of cyclic AMP from ischemic brain into cerebral venous blood seen in the steady state was abolished after therapy. Cerebral hemodynamic studies suggest a functional balance between monaminergic neurogenic influences in the control of cerebral circulation. Imbalance of such controlling factors in ischemic brain may lead to paradoxical vascular responses to induced hypertension and hypotension. PBZ and PPL enhance such responses perhaps by increasing central neurotransmitter turnover and release. Further shift toward cerebral anaerobic metabolism may occur in ischemic brain following the use of phenoxybenzamine and propranolol. Worsening of neurological deficit occurred in four cases. Combined therapy with PBZ and PPL does not appear beneficial in the therapy of patients with recent stroke.


Action of beta-adrenergic blocking agents on the urethral pressure profile. The action of beta-adrenergic blocking agents on the urethral pressure profile was studied. Sotalol, 20 mg, and inderal, 7 mg, were administered intravenously. Whereas the alpha-adrenergic blocking drug phentolamine, as already known, changed the maximum value of the pressure profile with an average decrease of 33%, the beta-adrenergic blocking drugs did not show any action at all. There was no difference between the results obtained with Sotalol and Inderal.


[Urodynamic measurements in enuretics].

[Urodynamic measurements in enuretics]. Distal urethral stenosis in girls as well as meatal and bulbar narrowed urethral segments in boys are still subjects of discussion about their pathologic value in the literature. The urodynamic findings in enuretic children by urethral pressure profile and cystometry frequently point to a outflow resistance. Calibration with bougies à boule, urethroscopy and permictional cysturethrography disclose such urethral narrowing. The survey of our own 107 enuritic children shows that urethrotomy has given good results relative to urodynamic data. The effect of methantheline medications consists in suppressing the hyperactivity of the detrusor.


Conservative bladder treatment in myelodysplasia. Differentiation of patients by cystomanometry. Urodynamic evaluation was performed in 75 patients with congenital neuropathic bladder. Concerning treatment the most important parameters were detrusor tone, detrusor activity and bladder outlet resistance. Based on these findings individual conservative therapy was applied. Reflux or dilatation of the upper urinary tract found in 26 children could be controlled by drugs or transurethral operations in 20, urinary diversion had to be done only 4 times. 26 children were selected for intensive treatment of incontinence; in about 50% satisfying urinary control was achieved. These results still need long-term observation. The main interest, however, was to postpone irreversible surgery and to gain time for possible better treatment in the future.


[Treatment of hypertonus in diabetes mellitus]. When pathophysiological and pathogenetic aspects of hypertension are taken into consideration with special regard to diabetes mellitus the exhaustion of the "insulin enhancement" within the cerebrovisceral functional systems (Baumann) are discussed and the authors enter possible connections of diabetes mellitus to the renin-angiotensin-aldosterone system. After explanation of the diabetogenic and antidiabetogenic pharmacodynamic qualities of the antihypertensive drugs adequate therapeutic recommendations are proposed summarized in a figure. The authors conclude that for the present antihypertensive therapy in diabetics taking into consideration the references reported on there are sufficient possibilities of treatment for all degrees of severity of hypertension. Such preparations as Rausedan, Disotat, Dopegyt appear as particularly suitable; moreover, the beta receptor blockers, Haemiton, Depressan as well as Guanitil and Pargylin prove to be possible or without disadvantage, respectively. Especially when diuretics are described an exact control of the metabolism should be carried out.


[The reaction of chorion epitheliums of human placentae to beta-sympathocomimetics (author's transl)]. The enzyme histochemical response of chorionic epithelium after treatment with Dilatel has been examined on 50 placentae of classified eutrophic premature and full-term births. In relation to the degree of damage to trophoblasts at the start of treatment and to dosage the response is mobilisation and further differentiation of Langhans cells and their transformation into mature plasmodium. The relevance of these results for metabolic transport and hormonal synthesis in the feto- maternal metabolic barrier and for the chance of therapeutic effects on insufficiency of the placenta is discussed.


[PH-static pectin esterase analysis in sweet cherries (author's transl)]. For the analysis of pectin esterase (PE) activities in sweet cherries some methods, as described in literature, were tested as to their usefulness in this specific range of application. The PE activities in dependence of the methods of extraction, the pH-value and the temperature were examined and a suitable procedure was achieved. With this method the PE activities in deposited sweet cherries were analyzed.


[Phospholipase D - a review (author's transl)]. Phospholipase D (phosphatidylcholine-phosphatidohydrolase, EC 3.1.4.4) hydrolyses lecithin into phosphatidic acid and choline. A review is given on the properties of phospholipase D described in the literature; it deals with the occurrence and distribution of phospholipase D in higher plants, with it's pH and temperature, substrate specifity, activators, inhibitors and with occurrence and properties of bacterial phospholipase D.


[Differential pharmacotherapy of neurotic conditions (comparative effectiveness of benzodiazepine derivatives)]. The effectiveness in treating borderline states to a certain degree depends upon the pole (sthenic or asthenic) of the corresponding disturbance. Tranquilizers are the preparations of choice in the treatment of disorders of an asthenic pole (psychopathy of the asthenic range, neurotic states). In borderline conditions of a sthenic pole the effectiveness of tranquilizers is equal or sometimes is even less than in therapy with small doses of neuroleptics. In treating neurotic conditions tranquilizers of the benzodiazepine group can be ranged in the following succession: nitrazepam, chlordiazepoxide, medazepam, oxazepam, diazepam, lorazepam. This preparation is a continuun of an increasing psychotropic activity.