Anal sphincteric pressure studies in complete rectal prolapse. Anal sphincteric pressure studies of patients with complete rectal prolapse demonstrated that: 1) The resting yield pressure of the internal anal sphincter in patients with complete rectal prolapse was not significantly different from that of control subjects. Thus, it seems to have no role in the etiology of prolapse. 2) The maximal sphincteric pressure of the external anal sphincter was significantly less in patients with prolapse than in controls. This suggested weakness in the effective functional power of the external anal sphincter in complete prolapse. 3) Anal continence could be achieved by the ability to maintain full contraction of the external anal sphincter for more than 40 seconds, which was the minimum for control subjects. Incontinent patients could not do this.


Intestinal gas in ulcerative colitis.

Intestinal gas in ulcerative colitis. Intestinal gas was measured planimetrically on plain abdominal films from 25 healthy subjects and 47 patients with active ulcerative colitis (mild, moderate, severe and toxic megacolon). Compared with controls, significant colonic distention was found in toxic megacolon. Gas in the small bowel was significantly increased in toxic megacolon and in severe colitis but was within the normal range in the mild and moderate forms. Two groups of patients with severe colitis were identified, showing either normal or increased gas content in the small bowel. Two of seven patients in the latter group developed toxic megacolon in spite of intensive medical treatment. Intestinal gas values showed a linear correlation with arterial blood pH, ESR and body temperature. No correlation was found between intestinal gas and other features of severity. It is suggested that an abnormal collection of gas in the small bowel loops associated with metabolic alkalosis corresponds to an early stage of a toxic complication ("impending megacolon").


Idiopathic ulcerative colitis in Istanbul: clinical review of 204 cases. A clinical review of 204 cases of idiopathic ulcerative colitis (IUC) seen in an insurance hospital in Istanbul during a period of nine years is presented. The criteria of diagnosis were based on history and results of rectosigmoidoscopic, biopsy, and barium-enema examinations. In the majority of cases (74 per cent), the disease manifested in the mild form, despite a history of one to five years' duration at the time of diagnosis. These patients usually had single attacks, with recovery in reponse to treatment. The mortality rate for the whole series was 3.9 per cent. Death occurred in eight cases of patients who had the severe form of the disease involving the entire colon, with fulminating courses. One additional death was due to an accident. Treatment consisted of a high-protein, low residue diet, vitamins, rest, sulfa drugs and steroids. Azathioprine, in addition, was used in fulminating cases. Surgery supplemented medical therapy in 19 cases. Indications for surgical treatment were resistance to medical management, cancer, and polyposis. Only two patients (1.0 per cent) were found to have cancer during the follow-up period. These two were operated upon. Idiopathic ulcerative colitis is not a rare entity; with awareness and use of appropriate diagnosis facilities, more cases are being discovered.


Insulin and glucagon levels in liver cirrhosis. Relationship with plasma amino acid imbalance of chronic hepatic encephalopathy. Alterations in insulin and glucagon levels might account for the plasma amino acid imbalance of cirrhotics. In order to verify this hypothesis we evaluated basal insulin, glucagon, branched-chain amino acids, aromatic amino acids, and free tryptophan in 13 controls and 37 cirrhotics divided on the basis of their mental state; in 4 patients the hormonal and amino acid patterns were sequentially studied during various stages of encephalopathy. Glucagon is high in cirrhotics and progressively increases with the worsening of the mental state. Free tryptophan and aromatic amino acids show a similar behavior and significantly correlate with glucagon levels (r = 0.67 and r = 0.81, respectively). On the other hand insulin levels, which are high in cirrhotics without encephalopathy, fall in the presence of deep coma. Insulin did not correlate with any of the plasma amino acids considered. Our data suggest that the catabolic state associated with increased glucagon levels may account for some of the alterations in the plasma amino acid profiles of cirrhotics. Portal-systemic shunting does not seem to be the common cause of both hyperglucagonemia and hyperaminoacidemia. Decreased branched-chain amino acid levels may be related to factors different from those involved in the alterations of carbohydrate homeostasis.


Comparative study of a standardized senna liquid and castor oil in preparing patients for radiographic examination of the colon. X-Prep Liquid, used as a radiologic bowel evacuant, was found to be more effective, better tolerated, and more readily accepted than castor oil. The efficacy of a single full dose of this peristaltic stimulant was confirmed, and a divided dose of X-Prep Liquid was practically as effective and produced less griping and cramping. This less intensive divided-dose approach appears to be appropriate, especially in aged or debilitated patients.


Inhibition of rat basal pancreatic secretion by intraduodenal bile. The effect on basal exocrine pancreatic secretion of diversion from and reintroduction into the duodenum of bile has been studied on conscious rats provided with pancreatic, biliary and duodenal fistulae. Diversion of bile from the intestine augmented protein output by 30%. After an eight-hour diversion recirculation of bile into the duodenum reduced pancreatic protein output by 30%; volume being not significantly modified. When either bile was diverted or the main bile duct was ligated, a similar inhibition of protein secretion was observed after intraduodenal injections of 20 mM solutions of taurocholate, taurochenodeoxycholate, chenodeoxycholate, and cholate, and of synthetic mixed micelles (bile salts, lecithin). Inhibitory action of bile salts on pancreatic secretion was seen equally whether or not the bile salts were in free or conjugated form or pancreatic juice returned to the intestine. We conclude that unlike man and the dog, bile as well as pancreatic juice inhibits the basal pancreatic exocrine secretion of the rat.


A clinical scoring system for chronic inflammatory bowel disease in children. A clinical scoring system for the assessment of children with chronic inflammatory bowel disease has been devised. A close correlation is demonstrated between severity of disease and the level of serum albumin. The clinical score is simple to perform, sensitive to changes in clinical status, reproducible by different observers, and specifically designed to evaluate inflammatory bowel disease in children and adolescents. The clinical score is a useful adjunct in the management of children with chronic inflammatory bowel disease and can be used in prospective studies of various therapeutic modalities.


Malignant histiocytosis of the intestine. Four cases of malignant histiocytosis of the intestine (MHI) are described in detail, with emphasis on the clinical features and laboratory findings that may lead to a diagnosis. MHI is a rapidly progressive, usually fatal condition, which may occur in a setting of adult celiac disease or apparently spontaneously; all patients, however, have villous atrophy and crypt hyperplasia of the jejunum. Characteristic symptoms are malaise, weight loss, abdominal pain, and diarrhea followed, after a period of weeks or months, by acute small intestinal obstruction, perforation, or bleeding. Because of the high mortality associated with MHI, suggestive symptomatology and investigations should, in the absence of a definitive diagnosis, lead to an urgent laparotomy with a view to chemotherapy if the diagnosis is made.


Esophageal motility in progressive systemic sclerosis (PSS). Comparison of cine-radiographic and manometric evaluation. The evaluation of structural and functional abnormalities of the esophagus by manometry (using perfused tubes) and cine-radiography were compared in 25 subjects with progressive systemic sclerosis (PSS). Motility by both procedures was definitely abnormal in 19 subjects and normal in 3. The remaining 3 subjects had abnormal motility on manometry, coupled with cine-esophagrams interpreted as normal. Many structural abnormalities not demonstrated by manometry were identified by cine-radiography. Therefore, the initial diagnostic examination of motility in PSS should be the cine-esophagram.


Follow-up of a flatulent patient.

Follow-up of a flatulent patient. This paper describes a low-flatulence diet developed by an extremely flatulent patient. Based on meticulous recording of each passage of flatus, the patient employed an elimination diet to determine what foods were responsible for his gas production. The diet reduced the frequency of his gas passage from 34 +/- 7 to 17 +/- 5 times per day (normal: 14 +/- 6) and similar reductions were observed by two other flatulent patients during adherence to the diet. The rectal gas of each of these subjects largely consisted of two gases (CO2 and H2) which result from bacterial fermentation of carbohydrates. The diet, which is low in lactose and wheat products, presumably minimizes the quantity of carbohydrates delivered to the colonic bacteria.


[Diuretic resistant ascites in hepatic cirrhosis and renal insufficiency (author's transl)]. In decompensated hepatic cirrhosis the glomerular filtration rate is reduced. Use of diuretics frequently leads to hyponatraemia, hypotension, hypovolaemia and oliguria. The ensuing renal insufficiency is reversible when the peritoneal fluid is redirected into the vascular system. For this purpose a subcutaneously implantable pump developed by Agishi was used in a 37-year-old patient permitting drainage of the ascites from the peritoneal cavity into the superior vena cava using an actively operated pumping mechanism. Use of the pump in the patient abolished the ascites, considerably improved renal function, equilibrated electrolyte metabolism and improved renal response to diuretics.


[Immunity against poliomyelitis in the German Federal Republic (author's transl)]. The immunity of the populations of several countries of the GFR against poliovirus 1, 2 and 3 was investigated in 11 laboratories. Sera of 4707 persons aged 0 to 30 years were assessed for neutralising antibodies (serum dilution 1:4) against the 3 types of poliovirus. 34.5% of the 4707 investigated sera had no neutralising antibodies at least against one type of the poliovirus, 4.7% showed no antibodies against all 3 types of the virus. Especially children aged 0 to 4 years were protected incompletely against the 3 types of poliovirus. In comparison with similar investigations of 1969 and 1972 no decisive change of immunity of the population of the GFR against poliomyelitis has occurred.


[Serum thyroglobulin estimation for follow-up of patients with thyroid carcinoma (author's transl)]. Thyroglobulin concentrations were determined radioimmunologically in the sera of 53 patients operated for thyroid carcinoma. 37 patients without metastases or recurrence had either very low (up to maximally 15 ng/ml) or non-demonstrable thyroglobulin concentrations, whereas 16 patients with metastases showed values of more than 40 ng/ml up to maximal values of more than 1000 ng/ml. In the majority of patients follow-up controls, in part up to 2 years, were performed. A far-reaching conformity of thyroglobulin concentrations with scintigraphic or clinical findings of metastases was shown. Thyroglobulin estimation in operated thyroid cancer patients is thus an important contribution to the aftercare.


[Sorbitol and xylitol in post-operative infusion therapy (author's transl)]. The effect of a 24-hour continuous infusion of sorbitol in the recommended maximum dosage of 0.25 g . kg-1 . h-1 or of xylitol in the recommended maximum dosage of 0.125 g . kg-1 . h-1 on metabolic parameters was investigated in seven healthy adult men. The results demonstrate the continued applicability for longer than the recommended time as well as the acceptability of continuous infusion of polyols used clinically with combined solutions.


[Nosocomial infections with Providencia stuartii (Proteus inconstans) (author's transl)]. 48% of all isolates of Providencia stuartii obtained within a period of one year, originated from the urine of catheterised patients, whereas another 37% were found in the respiratory tract of patients with intubation. The incidence of Providenica stuartii correlated with the period during which iatrogenic measures had been applied, as well as with a preceding course with antibiotics.


[Treatment with clomiphene of endocrine primary and secondary infertility in women (author's transl)]. Clomiphene (Dyneric) in a daily dosage of 100--300 mg, partially combined with HCG (n = 12), was used in the treatment of 86 women aged 19 to 39 years with primary or secondary infertility of endocrine origin in 296 menstrual cycles. In 67 cases (77.9%) ovulation could be induced and in 38 cases (44.2%) pregnancy occurred. In addition, in 4 cases pregnancy occurred two months after cessation of treatment. Combination therapy with HCG was successful in some of the cases resistant to clomiphene.


[Frequency of life-threatening complications associated with exercise testing (author's transl)]. Most of the statistics on complications of ergometric exercise tests come from the United States and are largely related to treadmill ergometry. A questionnaire was sent in the summer of 1978 to 198 investigative units in the German-speaking regions. The results of 1065 923 person-tests were made available. Exercise testing of 353 638 sports-persons revealed no serious complications. On the other hand, testing of 712 285 patients, predominantly with coronary heart disease, lead to 17 deaths and a total of 96 life-threatening complications. The result of this survey indicates that one must expect one such complication for every 7500 ergometry tests. The danger of pulmonary oedema on exercise in recumbency is about five times higher than that on sitting or standing. The most frequent complication was ventricular fibrillation. A defibrillator should therefore always be immediately available during exercise tests.


[Localised aspergillosis and oxalosis of the lung caused by aspergillus niger: soil of ornamental plants as a reservoir of aspergilli (case report) (author's transl)]. Haemoptysis occurred in a 64-year-old man with a history of pulmonary tuberculosis, negative for M. tuberculosis. Precipitating antibodies to Aspergillus niger were found in serum and the fungus found in sputum. Autopsy revealed aspergilloma, colonization of the pulmonary cavity by A. niger and local oxalosis if the cavity wall. Ornamental plant soil containing A. niger conidia, as well as the air in the patient's living-room, was the probable source of infection.


[Scientific work in the training of health personnel]. This document makes a series of statements about the limitations to scientific and technological development in Latin America and about recent trends in efforts to overcome them. The writer reviews the situation regarding health research in the Region and lists the respective shortcomings: "it is meager and disjointed, does not spring from the health problems of Latin American countries, and--like the training of health manpower, and of physicians in particular--is seen as entirely divorced from social reality, responding to outside influences that are sometimes entirely extraneous to the countries' own needs." She emphasizes that, while many health manpower training centers are striving to make their instruction more relevant to real life in their countries, no attempt is made to develop a scientific understanding of the health problems to which the educational process must be geared. She analyzes the role of research in student training and regards it as important to keep in mind that both research and instruction must aim for the same goal: development of science and technology in the service of the community. In closing, she asserts that the Latin American university must be committed to science in the service of society, which means that it must pass tha knowledge on to the population and join with it in the solution of its problems.


[Social medicine and medical education]. The author reviews the establishment of social security in Brazil from its origins in 1923 to the establishment of the National Institute of Medical Care and Social Welfare in 1977. He highlights the salient developments in the history of medical education in his country and analyzes the contributions of the welfare system to the training of the physician, particularly through student training in hospitals. The author is of the view that the introduction of social medicine into medical education, including the articulation of social welfare with the university hospitals, would be most salutary for the programs of the national health system.


[The community health technician and alternative in the training of health manpower]. This paper describes the general conditions of the social and economic dynamics of the rural area, with emphasis on the development of the factors that affect health in Mexico, and briefly analyzes the system for the education and training of manpower for health care. The author presents arguments in support of an alternative proposal for the training of the "community health technician" as a professional produced by four years of study following graduation from secondary school, and trained to take measures that contribute to the integral development of the community by acting upon the factors involved in the occurrence of pathological states, and to be the first contact for persons with medical problems. The course of training is described in terms of its ultimate purpose, which is improvement of the health status of a rural community, and of the general objectives in the "community development" and "medical care" areas. The course is administered in 25 modules as follows: four introductory modules to acquaint the student with the requirements for dealing with the areas, 11 modules on community development, eight modules on first-contact medical care, and the last two for practical exercises and community work, in which the student is required to bring all his knowledge to bear on a given community. Lastly, the course content of each semester is described together with the distribution of the theoretical and practical work in each module, and the outlook for its success, which points to the possibility of incorporating this resource into programs for extending coverage to rural areas.


[Minimum requirements for the establishment of medical schools. Division of human resources and investigation. PAHO/WHO]. This paper was presented as a reference document for the Working Group on the subject that met at Salvador, Bahia, Brazil, in December 1977, for the purpose of analyzing the recommendations presented in the report on Basic Principles for the Development of Medical Education in Latin America and the Caribbean Area, and to consider the proposed alternative ways of implementing them. It provides an introduction to each of the main topics that were to be considered by the Working Group, namely: socioeconomic aspects, health practices and the training of medical manpower; the inter-relations between the educational process and health services; institutional and program characteristics of institutions that produce physicians. It also refers to the efforts that have been going forward in the last few years in some physician-training centers, in the form of innovative projects for the teaching of medicine, including early participation of the student in the health practice and his incorporation into the various levels of care; the development of processes for the integration of teaching and service, and, in some cases, of teaching, service, and research; interdisciplinary coordination; the striking of a balance between the biological and social sciences; and further emphasis on study of the social sciences in their applications to the health-illness process.


[Effect of halothane (narcothane) on intrauterine fetal development]. The authors examined the effect of chalotane (narcotann ne-Spofa) on the development of a rat fetus. The rats were divided into groups and were narcotised for a period of 4 hours as well as 4.5 days. One of the group was narcotised from the 8 to the 13 day of gestation. Narcosis was made in chambers with dynamic inhalatory regimen at concentration of narcotane of 10 mg/m3 and 250 mg/m3. There was blastopathogenic effect of narcotane, manifested by an early resorption of nidaded ova, by nonspecific action on the fetus, which inhibited growth and development of the fetus and raised the mortality of the fetuses. The amount of estriol was diminished in mothers, treated with 250 mg/m3 of the drug.


[Changes in the perfusion of the internal organs of rabbits with experimental atherosclerosis treated with a protein hydrolysate]. The authors examined the vascularization of the internal organs of rabbits with experimental atherosclerosis, induced by the method of Sapirstein with 86-Rubidium. The experiments were carried out on male rabbits of the strain Cincilla, fed with cholesterol in a dose of 0.2 gm/kg of body weight daily for a period of 90 days. Part of the animals were treated with protein hydrolysate in a dose of 5 ml/kg of body weight subcutaneously, but the remaining part of the animals-with saline. There was a reduced vascularization in heart, kidney, intestine, liver, adrenals, pancreas, and other internal organs in rabbits fed with cholesterol and treated with saline. Administration of protein hydrolysate had protective effect on the vascularization of the organs accumulation of 86-Rubidium in a large part of the animals presented values higher than rhose of the control group. The authors suggested that under the influence of amino-acids from the protein hydrolysate the state of the endothelial cells was stabilized and the local, feactions of vascularization were stimulated as well.


[Effect of thyrotropic hormone on the iron content and iron-binding capacity in the milk of rabbits]. The authors administered thyreotropic hormone in a dose of 2 international units/kg of body weight on lactating rabbits intramuscularly. Concentrations of iron and iron-binding capacity in milk were examined at different days (from 7 to 21 days after delivery) of the lactation period of the animals. The obtained results suggested an inhibiting effect of thyreotropin on the content of iron and iron-binding capacity in milk after the first day of treatment. Later there was a gradual recovery of values almost to the initial values of the control day, which indicated transitory and comparatively quickly disappearing hormonal effect. The presumed mechanisms for this effect of thyreotropic hormone were discussed.


[Effect of laser irradiation on the serological and morphological indices of experimental immune reactivity (a preliminary report)]. The authors examined guinea pigs, irradiated for a period of six days with helium-neon lazer according to a scheme, proposed by them. They determined the changes in the complement serum activity, blood level of heparine and histamine as well as histologic changes in adrenals, liver and spleen. When they compared the control animals (nonirradiated) with the experimental animals, they established a statisticaly significant elevation of the complement activity in serum, a tendency to lowering of histamine with an increase of heparine and hyperplastic reaction in zona glomerulosa of the adrenals. The obtained results suggested stimulation of immune mechanisms with antiallergic and antinflammatory effect.


[Biomechanical studies of rabbit tendons after repeated injections of corticosteroids]. The purpose of investigation was to determine and compare the mechanical properties of rabbit tendons, injected with celestone as well as noninjected. The authors accepted the dynamic module during cyclic loading and the damaging tension reduced to an unit of body weight of the rabbit. As a result of the experimental biochemical studies they found that tendons, injected with corticosteroids, presented reduced strength and increased deformity in comparison with the noninjected tendons. Histologic examinations, performed additionaly, revealed that the functional properties of the tendons, injected with corticosteroids, were altered before the occurrence of structural changes in the tendinous tissue.


[Comparison of the decurarizing and median lethal doses of 2-aminopyridine salts]. The authors determined LD50 of 2-aminopyridine hydrochloride, 2-aminopyridine jodmethylate, 2-aminopyridine methyl-para-toluolsulfonat and pymadine (4-aminopyridine hydrochloride) in mice and rats after subcutaneous administration. They found that doses of the same compounds during indirect stimulation of m. gastrocknemius removed myorelaxating action of (+)-tubocurarine. LD50 and decurarizing doses of jodmethylates and methyl-para-toluosulfonat were higher than LD50 of hydrochloride of 2-aminopyridine. When LD50 was compared with the decurarizing dose of 2-aminopyridine methyl-para-toluolslufonat, its lower toxicity and potential perspectivity for practical application as an anticurare agent was indicated.


Central nervous system action of bombesin: mechanism to induce hyperglycemia. Bombesin acts within the brain to produce a prompt and sustained hyperglycemia, hyperglucagonemia, and relative or absolute hypoinsulinemia. Bombesin does not decrease plasma glucose turnover. Acute adrenalectomy but not hypophysectomy prevents hyperglycemia and hyperglucagonemia after intracisternal administration of bombesin. Administration of bombesin into the lateral ventricle of awake, unrestrained animals results in elevation of plasma glucose, preceded by a significant increase in plasma epinephrine and no increase in plasma norepinephrine or dopamine. Systemic administration of somatostatin prevents bombesin-induced hyperglycemia and hyperglucagonemia. These data support the conclusion that bombesin acts within the brain to increase sympathetic outflow resulting in increased adrenalmedullary epinephrine secretion, followed by depression of plasma insulin and elevation of plasma glucagon and glucose.


The hypothalamic-pituitary-gonadal axis during hyperthyroidism in the rat. The rat, an animal without testosterone-estrogen-binding-globulin, was treated with L-T4 to the point of hyperthyroidism in order to study the hypothalamic-pituitary-testicular axis during this condition. Hyperthyroidism led to a significant decline in serum FSH, a fall in serum LH which was not satistically significant, and no change in serum levels of testosterone or estradiol. Testes of hyperthyroid rats produced significantly more testosterone during in vitro incubations than did the testes of control animals. We conclude that hyperthyroidism in the rat leads to a fall in FSH levels either via direct pituitary suppression or via accelerated FSH metabolism. In addition, in vitro studies suggest that excess thyroid hormone may stimulate intratesticular 17 beta-hydroxysteroid dehydrogenase.


Properties of nuclear and cytoplasmic estrogen receptor in the rabbit corpus luteum: evidence for translocation. Nuclear and cytoplasmic estrogen receptors have been identified and characterized in the rabbit corpus luteum, and validated methods are described for the measurement of both unoccupied and total estrogen receptor. Binding was specific for the biologically active estrogens. Equilibrium binding analysis of cytoplasmic estrogen receptor yielded saturable, high affinity binding sites with a Kd of 5.4 x 10(-11) M. Two types of binding sites were found in the nuclear fraction: one with high affinity (Kd = 8.9 x 10(-11) M) and low capacity, the other with low affinity (Kd = 2.7 x 10(-8) M) and high capacity. In the presence of 0.4 M KCl, the sedimentation coefficients of nuclear and cytoplasmic estrogen receptors are 3.4S, while the value is 6.8S for cytoplasmic receptor in buffer without KCl. Twenty minutes after an iv injection of 2 micrograms 17 beta-estradiol, the available and total cytoplasmic estrogen receptors were depleted. This depletion was accompanied by concomitant and stoichiometric accumulation of receptor in the nucleus, indicating an apparent translocation of the receptor. In corpora lutea of normal rabbits, approximately 80% of the total nuclear receptor is unoccupied. Evidence is presented to suggest that nuclear receptor sites might be ordinarily occupied with estradiol, but during isolation of the nuclear fraction these sites become available or unoccupied. The identification of nuclear estrogen receptor and the phenomenon of translocation of cytoplasmic receptor to the nucleus suggest a similarity of estrogen action in the rabbit corpus luteum and other estrogen target tissues.


Effect of anterior hypothalamic lesions on neurohypophysial and peripheral tissue concentrations of somatostatin in the rat. Somatostatin (SRIF) is present in nerve endings in the median eminence (ME) and posterior pituitary. Hypothalamic SRIF containing neuronal perikarya are predominantly located in the anterior hypothalamic area (AHA), a region implicated in the inhibitory control of GH secretion. The effect of AHA lesions on SRIF in the ME, posterior pituitary, pancreas, stomach, and small intestine was studied in the rat in order to elucidate the source of ME and posterior pituitary SRIF and to determine if depletion of hypothalamic SRIF affects peripheral organ concentrations of the peptide. Lesioned animals showed a highly significant (P less than 0.01) 83% and 82% reduction in ME and posterior pituitary SRIF and to determine if depletion of hypothalamic SRIF affects peripheral organ concentrations of the peptide. Lesioned animals showed a highly significant (P less than SRIF concentrations in the pancreas, stomach, and small intestine of the lesioned animals. Plasma and pancreatic insulin and pancreatic glucagon were likewise unchanged. These data suggest that the hypothalamic SRIF pathway begins in the AHA, from where axons of somatostatinergic neurosecretory neurons project to both ME and posterior pituitary. AHA lesions have no effect on gut and pancreatic SRIF or pancreatic insulin and glucagon.


Growth of pancreas and gastrointestinal mucosa in antrectomized and gastrin-treated rats. Growth responses to endogenous and exogenous gastrin were examined in the pancreas and gastrointestinal tract mucosa. Rats were either antrectomized to remove the primary source of endogenous gastrin or subjected to a sham operation. Three weeks after surgery, half of the antrectomized animals were injected ip with pentagastrin (250 microgram/day) four times per day. Injections were carried out for a week. Antrectomy resulted in serum gastrin levels approximately one third of normal. DNA synthesis and DNA and RNA content of the pancreas and oxyntic gland, duodenal, and colonic mucosa were significantly reduced by antrectomy. In each case, pentagastrin treatment restored DNA synthesis and RNA and DNA levels to normal. Significant decreases in pancreatic and colonic weights in antrectomized animals were also completely prevented by pentagastrin injection. These results indicate that endogenous gastrin has an important role in the regulation of pancreatic and colonic mucosal growth, in addition to its already established similar function in oxyntic gland mucosa.


Dexamethasone effect on the phospholipid content of isolated fat cell ghosts from adrenalectomized rats. The lipid composition of sonicated ghosts from isolated fat cells has been investigated. Epididymal fat cells from adrenalectomized rats were incubated with and without 8 x 10(-8) M dexamethasone for 3 h. Phospholipids and cholesterol were isolated from membrane ghosts prepared from these cells. There was a 61% increase in membrane sphingomyelin from cells incubated with dexamethasone (P less than 0.025). No significant change was observed in other phospholipids, cholesterol, or fatty acid components of the phospholipids.


Actions of insulin and hydrocortisone on macromolecular synthesis in primary epithelial cell cultures from mouse mammary glands. Monolayer cultures of mammary gland epithelial cells were prepared from the abdominal glands of midpregnancy mice. After collagenase digestion of mammary tissue and separation by differential centrifugation, the isolated epithelial cells were cultured in Eagle's Minimal Essential Medium supplemented with 10% fetal bovine serum and insulin (6 micrograms/ml). Six days later, when the cultures were in log growth and nearly confluent, the effects of insulin and/or hydrocortisone on the rates of RNA, DNA, and protein synthesis were determined in a serum-free medium. At physiological concentrations, insulin enhanced the rates of uptake and incorporation of [3H]uridine into RNA, of [3H]thymidine into DNA, and of [3H]leucine into protein. Hydrocortisone was shown to be biphasic with regard to concentration in attenuating or augmenting insulin's effects on macromolecular synthesis.


No evidence for the existence of a species-specific renin substrate in plasma from normal and bilaterally nephrectomized rats. Renin substrate in plasma from normal and biolaterally nephrectomized rats was measured using an excess of rat or rabbit renin which had the same pressor activity when directly assayed in the rat. The amounts of angiotensin I generated with an excess of rat renin were similar to those generated with an excess of rabbit renin in plasma from normal and bilaterally nephrectomized rats. Further addition of an excess of homologous renin to the incubation mixture did not generate more angiotensin I from normal and bilaterally nephrectomized rat plasma which had been incubated before with an excess of rabbit renin. The isoelectric focusing profiles of plasma renin substrate from normal and bilaterally nephrectomized rats were almost identical using an excess of either rat or rabbit renin. It is concluded that there is no species-specific renin substrate for homologous renin in normal or bilaterally nephrectomized rats.


Independent inhibition of prolactin secretion by dopamine and gamma-aminobutyric acid in vitro. gamma-Aminobutyric acid (GABA) inhibits PRL release from incubated hemipituitaries in a dose-dependent manner. The maximum inhibition obtained with GABA is less than that obtained with dopamine. Its affinity is 100 times lower. The effect is blocked by picrotoxin but not by a dopamine inhibitor; alpha-flupentixol but not picrotoxin antagonizes dopamine inhibition. This indicates that dopamine and GABA inhibit PRL release through independent receptors. The hypothalamic extract contains sufficient GABA to inhibit PRL release in our in vitro conditions. Picrotoxin, however, does not significantly inhibit the nondopaminergic PRL-inhibiting activity of mediobasal hypothalamic extracts. Another nondopaminergic PRL-inhibiting factor, therefore, seems to be present in the hypothalamus.


Serum somatomedin activity and cartilage metabolism in acutely fasted, chronically malnourished, and refed rats. Serum somatomedin activity (SM-act) and cartilage metabolism were compared in acutely fasted, marasmic (M), and marasmic kwashiorkor (MK) rats. SM-act was estimated in the porcine bioassay. In vitro uptake of [35S]sulfate and [3H]methylthymidine in costal cartilage of the experimental animals during an incubation in medium immediately after sacrifice, called endogenous activity, and the effect of incubation in 20% normal human plasma after a preincubation of 22 h in medium only, called plasma responsiveness", were determined. Acutely fasted rats had lowered SM-act and a circulating heat-labile inhibitor. Endogenous activity and responsiveness of cartilage were depressed. MK rats (fed ad libitum a 0.5% casein, isocaloric food) showed a profound depression of growth and cartilage endogenous activity despite only partially reduced SM-act and increased responsiveness. M rats received normal food and were pair-fed with MK rats, consuming approximately 0.08 g/g BW . day. They showed very depressed SM-act and low endogenous activity, and responsiveness was increased, though less than in the MK rats. On refeeding M rats, SM-act and cartilage responsiveness increased, followed by an increase of endogenous activity. Catch-up growth was best related to [3H]methylthymidine incorporation by cartilage (endogenous activity). In conclusion, these two types of experimental chronic malnutrition induce a more diversified pattern than does acute fasting. During malnutrition, cartilage metabolism does not reflect bioassayable SM-act of serum but rather the other effects of the nutritional insult. On refeeding, the expected relationship of SM-act and cartilage metabolism is rapidly restored.


Changes in sex hormones and calcium regulating hormones with reference to bone mass associated with aging. Measurement of bone mineral content (BMC), intestinal 47Ca absorption, and calcium regulating hormones and sex steroids in serum were performed on 32 healthy aged subjects and 26 control young subjects. In BMC, there was a progressive fall after age 40, with the rate of decrease being greater in women than in men. A significant correlation was observed between BMC and testosterone in the men and between estrogens and BMC in the women, suggesting the possible importance of testosterone in men and estrogens in women in maintaining bone mass. Plasma PTH showed no change with age. However, the reserve capacity of the parathyroid was significantly reduced in the aged women. Serum levels of ionized calcium were low in aged subjects, indicating a possible alteration with age in the feedback control between ionized calcium levels and parathyroid hormone secretion. C-cell funtion was also decreased with age. Plasma 1,25-(OH)2D and 47Ca absorption tended to decrease with age. Age-related bone loss could be a reflection of the interaction of these hormonal imbalance occurring with age.


Postmenopausal and senile osteoporosis: current concepts of etiology and treatment. Postmenopausal osteoporosis and senile osteoporosis are heterogeneous disorders that appear to be caused by several nonhormonal and hormonal factors. Of nonhormonal factors, age-related bone loss, the degree of bone density achieved in young adult life, and dietary intake and absorption of calcium appear to be important. Hormones that may be important in pathogenesis are parathyroid hormone (PTH), estrogen, 1, 25(OH)2D, and possibly calcitonin. Postmenopausal estrogen deficiency accelerates bone loss by increasing responsiveness of bone to endogenous PTH. The resultant increase in release of calcium from bone is associated with normal or low values for serum immunoreactive PTH (iPTH) (except for a subset of 15% of the total which have high values and appear to represent a separate population). Some evidence suggests that subnormal calcium absorption, which is a common finding in postmenopausal osteoporosis and which may contribute to negative calcium balance, is caused by decreased conversion of 25-OH-D to 1,25(OH)2D. Treatment of osteoporosis with either sex steroids (by antagonizing the effect of PTH on bone resorption) or orally administered calcium with or without vitamin D (by decreasing PTH secretion) decreases bone resorption. Long-term therapy with these agents, however, decreases bone formation; thus, bone loss is only arrested or slowed. Although combined therapy with fluoride and calcium stimulates bone formation and appears to be capable of increasing bone mass, its long-term safety and efficacy in decreasing the the occurrence of fractures remain to be demonstrated.


Treatment of osteoporosis--with special reference to the coexistence of osteoporosis and osteomalacia. 1. The current status of treatment for osteoporosis at the osteoporosis clinic of the Department of Orthopaedic Surgery, Kobe University School of Medicine is reported. A study was made in these osteoporotic patients to investigate the relationships between pain and x-rays and also between pain and the clinical laboratory findings in this particular disease. 2. When pains in osteoporosis were classified into 4 grades, severity I through severity IV, the more severe pain was found to be associated more frequently with elevated blood levels of alkaline phosphatase. Many of the patients with severe pain tended to show indistinct trabeculation and sclerosis of the upper and lower margins of vertebral bodies on x-rays while some demonstrated looser's zones notably in the ribs. 3. A considerable portion of those patients who were receiving treatment under the diagnosis of osteoporosis were found to have evidence of osteomalacia, a finding pointing to the likelihood of coexistence of osteoporosis and osteomalacia. This possibility should therefore always be kept in mind when dealing with osteoporotic patients.


Biological activity of 1-alpha-hydroxy vitamin D3 in vitamin D dependency. The biological activity of 1(OH) vitamin D3 was evaluated in 2 cases of vitamin D dependency. For the improvement of serum chemistry and increment of urinary excretion of calcium 1(OH) vitamin D3 was 500--1000 times more active than vitamin D2. The administration of 0.05 microg/kg/day and 0.1 microg/kg/day of 1(OH) vitamin D3 were equally effective to keep the serum chemistry within normal limits. However, urinary excretion of calcium increased to an abnormal height on 0.1 microg/kg/day of 1(OH) vitamin D3. On the other hand, administration of 0.05 microg/kg/day of 1(OH) vitamin D3 kept both serum level and urinary excretion of calcium normal. It is suggested that 0.05 microg/kg/day is close to the optimum requirement of 1(OH) vitamin D3 in vitamin D dependency and this should correspond to the essential requirement of 1(OH) vitamin D3 in man.


Osteomalacic myopathy.

Osteomalacic myopathy. Muscles from two cases of osteomalacia were studied histochemically and electron-microscopically. Histopathological finding were common in these two cases. There are (1) myopathic changes such as scattered muscle fiber atrophy, necrosis, and internal uuclei, (2) derangement of intermyofibrillar network. and (3) type II fiber atrophy. Electron-microscopical finding corresponded well with light microscopical findings. These are distinct pathological features and deserves to be called osteomalacic myopathy. As the pathogenetic mechanism of this myopathy, phosphate depletion in the muscle cells resulting in disturbed glycolysis, and decreased vitamin D effects on muscle cells resulting in diminished calcium uptake by sarcoplasmic reticulum, are considered to be the most important two factors.


Vitamin D and osteoporosis.

Vitamin D and osteoporosis. In elderly people with marginal exposure to the sunlight, males showed higher serum 25-hydroxycalciferol than females, whereas in those with ample or poor sunlight exposure, serum 25-hydroxycalciferol was higher or very low, respectively, exhibiting no sex difference in the vitamin D metabolite levels. The male predominance in serum 25-hydroxycalciferol levels seen among some aged population would be explained, at least in part, by the result of animal experiment suggesting the stimulatory effect of testosterone on vitamin D biosynthesis induced by ultaviolet irradiation. Testosterone was, furthermore, shown to have hypocalcemic action, probably through suppression of bone resortopton in vitamin D depleted but not in replete rats. Clinical implication of these two-fold effects of testosterone observed in rats was discussed in relevance to male predominance in serum 25-hydroxycalciferol level and bone mineral content in the aged population.


Effect of 1 alpha-hydroxyvitamin D3 in rats with experimental renal osteodystrophy. A model of experimental renal osteodystrophy was established in the rats with chronic renal failure induced by partial nephrectomy and therapeutic effects of 1 alpha-hydroxyvitamin D3 (1 alpha-OH-D3) were studied. Male Wistar rats weighing 180 g were 5/6 nephrectomized and fed a normal diet (Ca and P : 1%) for 6 months. After the surgery, serum creatinine levels increased 60% and thereafter continued to rise gradually with their growth for 4 to 5 months, followed by rapid increase. The serum phosphorus levels were also elevated concomitantly and the serum calcium concentrations were normal. Marked bone resorption accompanied with hypertrophy of parathyroid glands was observed by histological examinations (Tetrachrome-Fuchsin stain, contact microradiography and H-E stain). The bone resorption seemed to be due to secondary hyperparathyroidism. Treatment with 0.25 micrograms/kg/day p.o. of 1 alpha-OH-D3 for 10 days in the uremic state resulted in remarkable new bone formation which was confirmed by histological examinations. These results clearly demonstrated that the reduction of nephron mass play a critical clue of renal osteodystrophy and 1 alpha-OH-D3 appears to have a good potential for clinical use in patients with renal failure and metabolic bone diseases.


Age-related changes of renal osteodystrophy. Bone changes in 138 patients under hemodialysis were evaluated by radiological methods. Bone mass as was assessed by clavicular score was reduced in patients with chronic renal failure compared with control subjects, especially in male patients, and showed the gradual decrease with aging in both sexes. The incidence of disappearance of lamina dura and that of vascular calcification increased with aging in chronic renal failure. Although serum PTH did not show much difference among various age groups, serum CT and calcium were significantly elevated in 20--24 years of age group compared with other age groups. The etiology of decrease of bone mass in male subjects was discussed from the standpoint of decreased gonadal activity.


Azotemic renal osteodystrophy; clinical features and bone pathology. During the hemodialysis treatment of 543 uremic patients for 10 years, significant complications concerning metabolic calcium disturbances, subperiosteal resorption, calcification of soft tissue or peripheral vessels, and fractures were noted. Significant elevation of alkaline phosphatase was induced for 5 years under hemodialysis using 5.0--6.0 mg/dl dialysate calcium, but not under 7.5 mg/dl dialysate calcium. Plasma immunoreactive parathyroid hormone (iPTH) values were abnormally high with a few exceptions, without relationship to serum calcium levels. Among the patients with chronic renal failure on dietary control, osteomalacic changes were predominant, but their iPTH values were not always elevated. When the patients were treated for a long time with hemodialysis, the mixed type of osteomalacia and osteites fibrosa appeared. Administration of dihydrotachysterol and 1 alpha-hydroxycholecalciferol to the patients on hemodialysis changed the mixed type of osteomalacia and osteitis fibrosa to the osteomalacic type with the marked reduction of osteoid seam thickness.


Influence of thyroid hormones on collagen content in tissues of guinea pigs. Collagen fractions content and level of collagen catabolites in body fluids were determined in normal, hypo- and hyperthyroid guinea pigs. An increase of urinary excretion of hydroxyproline and hydroxylysine as well as concentration of these amino acids in blood serum was found in hyperthyroidism, and a decrease was shown in hyperthyroid guinea pigs. Hyperthyroidism stimulated an increase of neutral-salt-soluble and acid-soluble collagen in skin and liver, and a decrease of insoluble collagen in skin as well as increase of all collagen fractions in bone samples. Hypothyroidism induced a decrease of all collagen fractions in skin and liver, and an increase of acid-soluble and insoluble collagen in bone samples.


[Secretion of growth hormone in pigs].

[Secretion of growth hormone in pigs]. Spontaneous rhythmic changes of growth hormone concentration were observed in plasma of pigs, ranging between 30 and more than 100% as compared to the initial values. These rhythmic changes should be considered when plasma GH is determined.


Complex cytophotometric analysis of hormone-induced alterations in the glucose utilisation of Tetrahymena. Insulin and adrenaline were both found to stimulate the glucose utilization of Tetrahymena, although somewhat differently. With exogenous sugar added, adrenaline always drops the glucose level in all regions of the unicellular, while the effect of insulin was less unequivocal.


[Inhibition of ovulation with 17-alpha-ethinyl-18-methyl-11-methylene-4-estren-17-ol plus ethinylestradiol]. A combined oral application of 30 micrograms ethinylestradiol with 50 micrograms 17 alpha-ethinyl-18-methyl-11-methylene-4-estren-17-ol (a newly developed progestagen) -- for 21 days resulted in a distinct antigonadotrophic effect, shown by hormone analysis (LH, FSH, estradiol and progesterone) in serum samples of three healthy and fertile women. A final recommendation on the daily dosage, however, depends on the results of clinical experimental investigation still in progress.


[Effect of 17-alpha-hydroxyprogesteronecapronate on sodium excretion and the renin-angiotensin-aldosterone-system in humans]. In seven healthy male subjects, a natriuretic effect of 17 alpha-hydroxyprogesterone caproate (17 alpha-OHPC) was demonstrated. Three of these subjects were kept on an uncontrolled diet and were examined over a period of 12 days. To the remaining four subjects, a single dose of 250 mg 17 alpha-OHPC was given intramuscularly after four days of intake of a chemically defined diet (Vivasorb). In this second test procedure, blood samples were taken in the recumbent position every two hours throughout a period of 12 h after the injection. For two more days and during the days before the administration of 17 alpha-OHPC, blood was taken at 8 a.m. before getting up from bed in same intervals, urine was collected for analysis of sodium and potassium excretion. During the first 12 h after the injection of 17 alpha-OHPC, the urinary sodium/potassium ratio significantly increased in all subjects. Plasma renin activity showed no characteristic changes at this time, whereas the plasma concentrations of aldosterone and cortisol decreased. The decrease of cortisol concentration started immediately after the injection and was more pronounced than that of plasma aldosterone. During the following 36 h, renin activity as well as aldosterone and cortisol concentrations in plasma showed an increase; in contrast, the sodium/potassium ratio decreased. On the basis of these results, the following effects of 17 alpha-OHPC are discussed: (1) an acute natriuresis which may be due to a competitive inhibition of aldosterone at the renal tubules, and (2) an inhibition of pituitary ACTH secretion or of adrenal steroid biosynthesis.


Seasonal fluctuation in lipid and cholesterol content of ovary, liver and blood serum in relation to annual sexual cycle in Heteropneustes fossilis (Bloch). Seasonal fluctuation in lipid content of ovary and liver and cholesterol content of ovary, liver and serum in relation to annual reproductive cycle in H. fossilis has been worked out. Reduction in lipid content of liver was associated with decrease in hepatosomatic index (HSI) in prespawning and spawning phases. But there was an obvious increase in the lipid level of ovary in the above phases which coincided with enhanced gonadosomatic index (GSI) records. Serum and ovary showed a subsidence in their cholesterol contents in prespawning followed by increased level during spawning period. Substraction in liver cholesterol started in prespawning and continued till spawning phase and thereafter regained upward trend. Lipid and cholesterol levels in all organs studied along with GSI and HSI returned to initial values by the end of postspawning stage. Administration of clomid, sexovid, PGE1 and PGF2 alpha for a week did not induce any change in HSI, GSI, lipid and cholesterol values of liver and serum. However, these drugs were effective in suppressing the ovarian cholesterol within a week. The above drugs seem to affect cholesterol level indirectly since they trigger gonadotrophin secretion which in turn probably accelerated cholesterol utilization in ovary for increased steroid hormone output.


Influence of histamine on estrogen-induced inhibition of compensatory ovarian hypertrophy in hemiovariectomized rats. The administration of histamine dihydrochloride (5 micrograms) into the lateral brain ventricle, H1-agonist IEM-813 (0.25 mg/kg) intraperitoneally, tavegil (0.05 mg/kg) intraperitoneally and dimedrol (50 mg/kg) subcutaneously did not change the rate of compensatory ovarian hypertrophy (COH) in hemiovariectomized rats. The treatment of rats with histamine or IEM-813 prevented the suppressive action of diethystilbestrol on COH, tavegil did not change and dimedrol enhanced the estrogen effect. Central histaminergic structures are suggested not be involved in the mechanism of PSH secretion. However, their stimulation inhibits the realisation of the negative feedback of estrogen.


Reactivity to estradiol of thymic cells from female mice before and after puberty. The reactivity to estradiol of thymic cells from female mice representing different stages of sexual maturation was investigated. It was found that estradiol administered in pharmacological doses can evoke in thymuses of ovariectomized mice changes imitating those observed during puberty with the reactivity to estradiol changing along with the process of sexual maturation. It is most likely that the changes of reactivity are due to extragonadal factors.


Studies on the effects of ethinyl estradiol and norethisterone acetate on the adrenal cortex and some other tissues in the rat. Alkaline phosphatase activity (AP) of the adrenal cortex of rats were determined under the effect of ethinyl estradiol (EE) and/or norethisterone acetate (NA), the two components of the contraceptive pill gyn-anovlar (Schering AG Berlin). A pathological study was also carried out to examine the effects of EE and NA on other tissues mainly the liver, lungs, spleen and ovaries. EE in a dose of 10 micrograms/day for 2 weeks caused a significant increase in the weight of the adrenal but no significant increase in the AP/g cortical tissue. The 25 and 50 micrograms doses for the same period caused a significant increase in both adrenal weight and AP. When treatment was prolonged to 6 weeks no effect on adrenal weight or AP was detected. The same finding was obtained with NA in a dose of 7 mg/rat/day for 2 weeks. The 14 mg dose of NA for the same period caused a significant increase in adrenal weight but no effect on AP. The 21 mg dose caused a significant increase in adrenal weight accompanied by significant decrease in AP/g cortical tissue. Treatment with NA for 6 weeks caused a rise in adrenal weight and AP with the 7 mg dose, then a decline in AP with the 14 mg dose, and a decline in both adrenal weight and AP with the 21 mg dose. As regards the effects of EE and NA on other tissues, EE was found to have a powerful stimulatory effect on the reticuloendothelial system (RES) as well as toxic effects on the liver. NA did not produce such lesions except for the large doses and prolonged periods of treatment. In addition NA produced cholestasis in the liver associated with staining of the liver cells with bile. Combination of EE and NA in the form of gyn-anovlar produced more powerful stimulation of RES and decreased the toxic manifestations of either component. As regards the ovaries, administration of 50 micrograms EE for 6 weeks produced profound hyperplasia of the granulosa cells of the Graafian follicles and inhibited ovulation, however, NA did not inhibit ovulation. With gyn-anovlar, the effect of EE on the ovaries seemed to predominate and ovulation was inhibited.


Indications for a brain uptake of labelled vasopressin and ocytocin and the problem of the blood-brain barrier. Fifteen seconds after intracarotid injection of [125J]-lysine vasopressin, [3H]-ocytocin, tritiated water or [3H]-inulin, the distribution of radioactivity in 18 regions of the rat brain and in the anterior pituitary was determined. Comparing the concentration of the different tracers (in % of injected radioactivity per g brain tissue), it is assumed that a small amount of the labelled neurohormones is taken up by the brain, indicating a penetration of the blood-brain barrier and/or an accumulation within the structures of the barrier system.


Free fatty acid release from human adipose tissue in relation to obesity -- effect of isoprenaline. The capacity to release non-esterified acids and glycerol from the abdominal subcutaneous adipose tissue into a medium containing different concentrations of isoprenaline was studied in 21 adults with different body weight (14 obese, 7 controls). The obese had a significantly lower maximum adipokinetic capacity (expressed as pD2) than controls. The significant decrease in pD2 in the obese was found to depend on the stabilization of the weight while the dynamic pD2 stage values of the obese did not differ from those of controls. The hypothesis is expressed that lower pD2 values may be related to the smaller decrease of body fat during weight reduction.


Radioimmunoassay of porcine growth hormone -- methodological studies. A double antibody radioimmunoassay for immunoreactive growth hormone in porcine plasma has been evaluated on the basis of dilution and recovery experiments as well as by examination of accuracy and reproducibility. The sensitivity was better than 0.10 ng/ml. The cumulated within-assay coefficient of variation was between 2--4% and the cumulated between-assay coefficient of variation was 9.6%. The normal fasting values correspond well to those of other investigators.


Inhibition of the 3 beta-hydroxysteroid oxidoreductase of Pseudomonas testosteroni by steroids. 55 Steroids of the estratriene and androstane type with substituents in pos. 16 alpha, 17 alpha or 17 beta were tested for inhibition of the 3beta-hydroxysteroid oxidoreductase of Pseudomonas testosteroni. Estratrien-3-ols were strong and competitive inhibitors (Ki less than 1 micron). Substituents in pos. 16 alpha of estradiol influenced the inhibitory activity distinctly. Substituents in 17 alpha- or 17 beta-position were of slight influence. 3-Methoxy estratrienes gave no inhibition of the enzymic 3 beta-OH-dehydrogenation. The 4-unsaturated 3-oxo-steroids tested were moderate inhibitors (Ki 2.4-70 micron). The activity was slightly influenced by 17 alpha-substituents. It was increased by 10 beta-substituents in the order H less than CH3 less than N3. The inhibition test can be used to select and eliminate very strong synthetic inhibitors, which are known to disturb the metabolism of steroid hormones.


Effects of methallibure (I.C.I. 33828) on the female reproductive tract of the Indian Desert gerbil (Meriones hurrianae Jerdon). Effects of methallibure (I.C.I. 33828) have been studied on the reproductive organs of female gerbils, Meriones hurrianae. Methallibure administration caused reduction of gonadal weight indicating suppression of pituitary gonadotrophins. In the ovaries of the treated females extensive atresia of follicles and of corpora lutea was observed. In addition methallibure interrupted the sex cycle, and a dioestrous vaginal pattern was retained throughout medication. A significant decrease in the level of RNA, protein and sialic acid in the uterus and vagina and of glycogen in the uterus was found. Histological and biochemical changes in the ovaries and uteri suggest a possible direct antioestrogenic action of the compound.


Urinary androgen- and estrogen excretion in men with pachydermia laryngis and cancer of the larynx. Considering the larynx as a hormone dependent secondary sex characteristic has previously led to successful antiandrogentherapy of pachydermia of the vocal cords, which may constitute a precancerous state. As a first step to further evaluate the endocrine state of patients with precancerous lesions or cancer of the larynx, the urinary excretion of 17-hydroxysteroids, 17-ketosteroids, testosterone and estrogens has been determined in male patients with pachydermia laryngis (n = 15) or cancer of the larynx (n = 20) as compared to controls with different other otorhino-laryngological affections (n = 20). No difference between groups was found in 17-hydroxysteroids and no significant difference in 17-ketosteroid excretion. The pachydermia group as a whole showed significantly increased levels of testosterone (p = 0.01) and estrogen (p = 0.04) of 64.6 +/- 39.9 microgram/24 hr testosterone versus 34.7 +/- 19.3 microgram/24 hr in controls and  31.7 +/- 16 microgram/24 hr in laryngeal cancer and 277 +/- 14.8 microgram/24 hr total estrogens versus 19.1 +/- 12 microgram/24 hr and 17.8 +/- 8.1 microgram/24 hr respectively. These data further support the idea of hormonal factors playing an important role in the pathogenesis of pachydermia and thus possibly cancer of the larynx. So far, however, they do not permit definite conclusions on the pathogenetic mechanisms involved.


Gonadotrophin determination in 24-h-urine by sensitive LH and FSH radioimmunoassays. Urinary Lutropin (LH) and Follitropin (FSH) were precipitated with acetone and measured by specific radioimmunoassays. Recovery experiments with special regard to urinary pH values were done by adding 125I-labelled LH and FSH to unprocessed urine. At pH 4.5 68.6% of LH and 66.1% of FSH were recovered. Increasing pH values up to 6.0 resulted in a significant recovery loss of 125-I-LH, but not of 125I-FSH. Immunoreactive FSH concentrations decreased significantly 6 and 48 hours after storage began at room temperature. In healthy males and females we found mean LH and FSH concentrations in 24-h-urine which were similar to those reported by others: LH: males: 22.6 IU/24-h; cycling females: 17.8 IU/24-h; postmenopausal females: 49.1 IU/24-h; FSH: males 6.0 IU/24-h: cycling females: 15.0 IU/24-h; postmenopausal females: 48.5 IU/24-h. Because of their high sensitivity and practicability, we believe that these radioimmunoassays are clinically useful approaches in assessment of pituitary and gonadal disorders in human subjects.


Study of plasma aldosterone in normal pregnancy, in pre-eclamptic women and in cord plasma of newborns. A radioimmunoassay without chromatography was used for the determination of plasma aldosterone in pregnancy. The mean values (+/- S.D.) of aldosterone concentration increased consistently from 23.2 +/- 5.3 ng/100 ml (n = 14) during the first trimester to 37.2 +/- 10.6 ng/100 ml (n = 17) during the second trimester and 64.0 +/- 18.8 ng/100 ml (n = 29) during the third trimester of pregnancy. The highest values were found at delivery (71.9 +/- 14.2 ng/100 ml; n = 21) and in the cord plasma of newborns (83.4 +/- 14.9 ng/100 ml; n = 21). Significantly lower plasma aldosterone values were found in the plasma of pre-eclamptic women during the third trimester of pregnancy (41.9 +/- 21.3 ng/100 ml; n = 11).


Study on the inactivation mechanism of androgens in rheumatoid arthritis: excretory rate of free and conjugated 17-ketosteroids. Unconjugated, sulpho- and glucurono-conjugated androgen hormone metabolites have been determined in the urine of patients with rheumatoid arthritis. An increase in the excretory rate of unconjugated 5 beta-reduced 17-ketosteroids and a decrease in that of 17-ketosteroid conjugates, especially in dehydroepiandrosterone sulphate and in the sum of dehydroepiandrosterone, etiocholanolone and androsterone glucuronoside were observed. In contrast to unconjugated metabolites, there was less significant change in the 5 beta-metabolite conjugates in urine. Corticosteroid treatment resulted in an additional decrease of metabolite excretion by patients. Further study is necessary to determine the causative factors in the altered steroid pattern observed in this severe, non-endocrine disease.


Regulations of plasma aldosterone in young hyperkalemic patients with stable chronic renal failure. In a group of four young patients with stable chronic renal failure and hyperkalemia sodium restriction induced a remarkable increase in plasma renin activity (PRA) and plasma aldosterone (PA), a decrease in the elevated serum potassium (SK) and a rise in potassium excretion. During high sodium intake the levels of PRA and PA were lower than those found in the healthy control group suggesting that enhanced suppressibility of the renin-angiotensin-aldosterone system (RAAS) was the main cause of hyperkalemia. During sodium restriction despite a marked increase in PRA and PA levels poor correlations were found between these variables indicating disorganisation within the RAAS and probably a diminished role for renin-angiotensin in the regulation of aldosterone production in three hyperkalemic patients with chronic glomerulonephritis. On the other hand, in the same patients significant correlations were found between fluctuations of SK and PA on constant normal and low sodium diets supporting the concept of an (at least) equal role of potassium and RAAS in the acute regulation of PA. A prominent role for SK was found in an unusual hyperkalemic patient with interstitial nephritis when PRA was suppressed and the elevated SK showed a definite postural rise inducing dramatic increases in PA in the upright posture. Reversion of the postural SK rise masked again the governing role of SK.


Relationship between insulin and somatotropin in obesity. The authors have estimated a correlation between the total insulin areas after glucose loading and total somatotropin areas during insulin-induced hypoglycaemia in 30 patients with obesity, as well as in a selected group of 16 patients with simple (essential) obesity. A significant negative correlation was found in both investigated groups. A new hypothesis assuming hyposecretion of somatotropin in obese subjects as a result of hyperinsulinaemia and subsequent increased somatomedin generation is suggested.


Basal and stimulated hyperinsulinemia in obesity: relationship to adipose-cell size. In 17 non-selected, non-hyperlipoproteinemic subjects without overt diabetes both adipose tissue biopsy and an oral glucose tolerance test (50 g) were performed. All persons were weight-stable at the time of investigation. A significant correlation between fasting insulin concentration and mean adipocyte volume was observed, whereas no correlation existed between ideal body weight index and fasting insulin level. Persons with larger adipocytes had elevated basal insulin levels as well as higher and longer lasting increments following the glucose challenge. They also exhibited significantly higher mean glucose levels during the OGTT. When these patients were matched for glucose tolerance with the subgroup having smaller mean adipocyte volumes, the difference in insulin levels was still demonstrable. This study underlines the importance of adipose-cell enlargement regulating basal and stimulated insulin output.


Changes in plasma oestradiol-17beta, progesterone, testosterone, LH and fertility after treatment with I.C.I. 80, 996. Fifty heifers were twice injected with I.C.I. 80, 996 and inseminated 72 h and 96 h after the second administration. Twenty eight of them (56%) became pregnant. Changes in plasma oestradiol-17 beta, progesterone and LH concentrations around the oestrus following the second injection were similar to those occurring in spontaneous oestrus. The pattern of testosterone secretion resembled that of oestradiol;-17 beta. The highest testosterone concentration (135 +/- 24 pg/ml) was measured on the third day after treatment with I.C.I. 80, 996.


Studies on the erythropoietic effect of plasma from anemic toads both with and without testis. Injection of plasma from experimentally induced anemic toad with intact testis increases erythropoiesis in starved toads evidenced by the increase of red blood cell, hemoglobin and hematocrit, whereas the plasma of castrated and phenylhydrazine-HCl treated anemic toad failed to do so. It can be suggested that the erythropoiesis stimulating factor (ESF) is produced from the testis of toad and the production of this factor (ESF) was found to increase during anemia in an attempt to correct the anemic condition.


A comparison of two proxy measures for morbidity. The use of standardised mortality ratios (SMRs) as a proxy measure of morbidity for resource allocation purposes in the National Health Service (NHS) has been widely criticised. The small number of deaths from infectious diseases makes it necessary to consider whether there are more appropriate measures. The standardised notification rate (SNR) was compared with the SMR for respiratory tuberculosis and it appears to be a better proxy for morbidity.


Some insights into Miettinen's multivariate confounder score approach to case-control study analysis. We have studied Miettinen's multivariate confounder score method of controlling confounding in case-control studies both theoretically and by simulation. The main conclusion to be drawn from out results is that the method will in many practical situations seriously exaggerate the statistical significance achieved, and its use is not to be recommended.


The sex differential in ischaemic heart disease: trends by social class 1931 to 1971. The comparison of trends in ischaemic heart disease (IHD) mortality in different social classes is confounded by historical changes in diagnostic techniques and statistical classification, and possibly by different standards of diagnostic accuracy in the different social classes. The problems can be circumvented by taking advantage of the fact that in middle age (45 to 64) the IHD death rate is much higher in men than in women. This large sex differential is not present in any of the other causes of death with which IHD might easily be confused and it is therefore relatively unaffected by diagnostic errors and variation in classification. The changes that have occurred in the sex differential in Social Classes I and V in England and Wales between 1931 and 1971 confirm anecdotal clinical reports that the male vulnerability to IHD appeared first in Social Class I (professionsl). By 1971 Social Class V (unskilled) had caught up, and the men in these two social classes now experience an almost identical excess in cardiovascular death rate compared with their wives.


The influence of a premarital conception and various obstetric complications on subsequent prenatal health behaviour. This paper is a companion to an earlier report on prenatal visiting patterns in Aberdeen, Scotland (McKinlay, 1970). It examines the following three main questions: (1) Is the emerging trend towards later maternity care among young nulliparae largely due to those who delay because of premarital conception? (2) If premarital conception is primarily responsible for this trend, is this pattern of visiting behaviour continued in subsequent pregnancies, and what variation is there in such behaviour--between, for example, different socioeconomic groups and age groups? (3) Does the presence of one or more obstetric complications associated with a first pregnancy or birth have an effect on subsequent prenatal health behaviour, and does this effect, if present, interact with, say, socioeconomic status, or the legal status of the first pregnancy? The paper concludes with a discussion of some policy implications of the findings.


Distance as an influence on demand in general practice. A survey of general practice in the London borough of Lambeth was analysed to discover how the distance from a patient's home to a medical facility affects the utilisation of that facility. It was shown that distance has a negative effect on utilisation for all population groups except men aged 15 to 64. The effect was especially marked for women, for the elderly, and for Social Classes III, IV, and V, which are the groups with highest utilisation rates. Some diagnostic groups singled out for analysis showed the same effect. These results are related to other studies and to an economic theory seeking to explain patterns of demand.


Metabolic adaptation to prolonged exercise. A study was undertaken to evaluate and to examine the role of substrate supply in 50 healthy subjects after long distance events, such as 10 km, 25 km, and marathon races. The metabolic, variables of carbohydrate metabolism were greatest in 10-km runners, with the highest increase in glucose, lactate, and pyruvate, while in marathon runners only moderate changes were observed. Marathon competitors gave the greatest decrease in insulin concentration whereas glucagon and cortisol showed a contrary tendency. As for lipid concentrations, the most remarkable point was that after the marathon competition the best runners had the highest increase in free fatty acids; the longer the race, the higher were the beta-hydroxybutyrate and acetoacetate levels after the competition. It is important to emphasize that the limiting factor up to 90 min duration is the competitor's ability to deplete the stores of glycogen. Beyond 90 min (or 25 km) the decrease in insulin, the rise in cortisol and the higher concentration of ketnne bodies found indicate a change in metabnlic response.


Factors influencing quantified surface EMGs. Isometric flexions of the elbow are studied in man. For the three joint angles studied, the torque, the surface EMG of the biceps brachii muscle, and the quantified EMG are recorded. The EMGs are picked up by means of bipolar electrodes located in such a way as to vary the interelectrode orientation, the interelectrode distance and the position on the muscle. Longitudinal placements collect stronger signals that transverse ones. Under certain conditions, the magnitude of the quantified EMG depends on the distance between the electrodes, and on their location on the muscle. The results are discussed in terms of conduction volume and detection volume.


Intra- and extravascular volume changes in the human forearm after static hand grip exercise. Studies have been conducted to evaluate intra- and extravascular volume changes and blood flow in the exercising human forearm by means of (1) combining plethysmographic and scintigraphic methods, (2) an indirect procedure using the relationship of blood flow and volume change from reactive hyperemia. A static hand grip exercise of 60% maximal voluntary contraction and 30 s duration increased the forearm volume by 3.03 +/- 0.65 ml/100 ml soft tissue, involving both the intra- and extravascular volume components. There is a quantitative and qualitative difference in the time course of change in these components, showing an extravascular part of about 50% for the 2-min post-exercise value and a substantially slower rate of recovery. Experiments involving muscle work at intervals (50% maximal voluntary contraction, 30 s duration, 2-min intervals) caused a further increase in extravascular volume. Furthermore, the study suggests that the flow-volume relationship from reactive hyperemia may be considered to be available for the determination of local blood volume changes in exercise hyperemia. The results are discussed in connection with the influence of anaerobic muscle metabolism and conclusions referring to this are drawn about the use of plethysmographic methods.


The perception of effort: an inductive approach. A theoretical model has been proposed relating physical effort to perceived exertion. The model has been applied to a comparative investigation of the perception of various forces exerted by the adductor pollicis muscle and the quadriceps in five male subjects. The increase in perception of effort with increasing applied force in both muscle groups has been shown to increase exponentially. A force constant, defined in the paper, as the applied force at which perception of effort approximates two-thirds of maximum seems to discriminate effectively between the muscle groups concerned. The description of psychophysical data in this concise quantifiable manner may offer better insight into physiological processes contributing to the appreciation of effort.


Serial isometric contractions under imposed myotatic stretch conditions in high-strength and low-strength men. The immediate effects of an imposed myotatic stretch on knee extensor force were studied in 12 high-strength and 12 low-strength men. Under nonfatigued pre-exercise conditions, significant tension increases of 6.5% for the high-strength group and 11.0% for low-strength subjects were observed as a result of the imposed stretch. An exercise treatment involving 28 serial isometic contractions, each of 5 s duration, with an intertrial rest period of 10 s was administered. This fatiguing exercise resulted in significant decrements in strength on the order of 28.0% and 18.5% for the high-strength and low-strength groups, respectively. A Similar treatment which included a 1 s imposed myotatic stretch during each trial resulted in a greater strength decrement for the low-strength group (26.4%) than for the high-strength subjects (15.0%). A neural factor involving the stretch reflex is tentatively suggested as a plausible explanation accounting for the observation that high-strength subjects fatigue faster than low-strength subjects under conditions of isometric exercise, while low-strength subjects fatigue faster than high-strength individuals in isometric exercise which is performed with an imposed stretch.


Influence of running pace upon performance: effects upon treadmill endurance time and oxygen cost. Three possible patterns of pacing (type 1, fast/slow; type 2, slow/fast; and type 3, steady rate) were compared over a 1400 m, 4 min run. The subsequent running time to exhaustion at 370 m . min-1 was significantly longer with a type 1 than with a type 2 protocol (P less than 0.05). The steady rate pattern gave results intermediate between type 1 and type 2 pacing. Data for oxygen debt and recovery heart rate confirmed the superiority of type 1 pacing. Possible explanations included (1) a reduction of inefficient anaerobic work, and (2) a greater mechanical efficiency associated with the better matching of required effort to a tapering physiological power. Runners should aim at a steady physiological rather than a steady physical load.


Post-competition blood lactate concentrations in collegiate swimmers. The purpose of this investigation was to quantitate post-competition lactate (LA) concentrations of swimmers during a competitive collegiate meet. Blood LA was measured by an enzymatic method on 23 subjects 5 min after each race event. The largest mean LA concentration of 25.7 mM/L was observed in swimmers after competing in the 200-yd individual medley. Swimmers in the 200-yd butterfly, back, breast and freestyle races had similar mean blood LA concentrations (ranging from 16.4 to 20.6 mM/L). Swimmers in the two longest events, the 500-yd and 1,000-yd free style races, had mean LA concentrations of 15.6 and 10.0 mM/L, respectively. To account for the effects of motivation, LA concentrations were measured following maximal effort noncompetitive 100 and 200-yd swims. LA concentrations were slightly greater in conjunction with faster performances for the competitive as compared to the noncompetitive 100 and 200-yd swims.


Anticooperative binding of L-tryptophan to tryptophanyl-tRNA synthetase from beef pancreas. Study at equilibrium by dialysis and changes in spectroscopic properties. Equilibrium dialysis and gel filtration studies show that tryptophanyl-tRNA synthetase from beef pancreas binds two molecules of L-tryptophan per dimer in an anticooperative way. The binding of tryptophan ellicits a series of spectroscopic changes in the protein as seen by absorbance, fluorescence and circular dichroism. The molar absorption change of the protein-tryptophan system upon formation of the complex is delta epsilon292 = 10 400 +/- 1000 M(-1) cm(-1) per dimer. Taking an initial symmetrical dimeric protein the two dissociation constants for tryptophan at pH 8, 25 degrees C are respectively K1 = 2.0 +/- 0.5 muM and K2 = 10 +/- 4 muM. They are respectively K1 = 1 +/- 0.25 muM and K2 = 20 +/- 8 muM if one considers a sequenced binding of the two tryptophan molecules. The dichroic band at 290 nm of the free protein disappears when tryptophan is bound. All observed changes are characteristic of tryptophan perturbation and none of tyrosine perturbation. They all exceed the effect that can be expected from the change in environment of the bound tryptophan molecules and modifications of the tertiary structure of the protein have to be taken into account to explain the observed spectroscopic data.


Changes in the frequency and diversity of messenger RNA populations in the course of myogenic differentiation. Complementary DNAs (cDNAs) were synthesized from polyadenylated RNAs of myoblasts and myotubes and used to analyze changes in the sequence complexity and frequency distribution of messenger RNAs during myogenesis in vitro. cDNA . polyadenylated-RNA hybridization kinetics show the presence of messenger RNA sequences specific for myotubes in fully differentiated muscle cultures. These sequences are accumulated just prior to fusion, as was shown by hybridizations of myotube cDNA and total cytoplasmic RNAs from cells at different stages of differentiation. The myotube cDNA can be enriched 10-fold in myotube-specific RNA species by a hybridization with cytoplasmic RNAs from myoblasts and subsequent removal of these hybridized sequences by hydroxyapatite.


Relationship between single-stranded DNA isolated from cultured muscular cells during differentiation and the transcription of messenger RNA. Single-stranded DNA (ssDNA), equivalent to about 2% of the total nuclear DNA, was isolated by an improved method of hydroxyapatite chromatography from native nuclear DNA of rat myoblast cells and myotubes of the L6 line. Small quantities of 125I-labelled ssDNA were annealed with a large excess of unlabelled DNA, cytoplasmic RNA and mRNA from myoblasts or myotubes. The results indicated that ssDNA belongs to the non-repetitious portion of the cell genome and is formed of two distinct molecular fractions. The major ssDNA fractions (75%) consist of non-self-reassociating DNA sequences and the minor fraction (25%) consists of self-reassociating DNA sequences. About 30--32% and 25--26% of ssDNA from myoblast represent DNA sequences complementary to total cytplasmic RNAs and polyadenylated RNAs respectively. Hybridizations of ssDNA with an excess of RNA from myoblasts and/or myotubes show differences in the abundance and the diversity of mRNA during mascular differentiation. These differences were confirmed by DNA-driven reactions between 125I-labelled polyadenylated RNA and ssDNA in great excess.


Photo-induced protein-RNA cross-linking in mammalian 60-S ribosomal subunits. Rat liver 60-S ribosomal subunits were submitted to increasing doses of radiation (253.7 nm), at 4 degrees C and 25 degrees C, as previously reported fro 40-S subunits. The existence of protein-RNA cross-linking was demonstrated by two methods. The first consisted in the separation of protein-RNA complex; the second was indirect, and took into account alteration either in the electrophoretic mobility of cross-linked proteins or the separability of 28-S RNA in a 4 M urea/3 M LiCl buffer. The peptide synthetase activity and the sedimentation characteristics of the particles irradiated at 4 degrees C were well preserved, but at 25 degrees C the large subunits were progressively inactivated and unfolded for doses higher than 2 x 10(18) quanta. The dose-dependent variations of protein cross-linkage determined by two-dimensional gel electrophoresis allowed us to distinguish those proteins which reacted at the lowest doses with a first-order reaction from those which cross-linked to RNA after a subtle modification of the subunit structure. At 25 degrees C, all proteins became low-dose reactive. The curve obtained for 28-S RNA cross-linkage was similar to that of the total protein moiety, while those obtained fro the 5-S and 5.8-S RNA (which were parallel) suggest a lower reactivity of these RNAs. As a general rule, proteins from the large subunits were more reactive to RNA than those from the small subunits. This could indicate differences in the organisation of the two subunits.


Binding of antibodies against histone H1 to unfolded and folded nucleofilaments. Rabbit antibodies to calf thymus histone H1 were purified by affinity chromatography on histone-H1--Sepharose and used as a probe for detecting histone H1 in the nucleofilaments prepared from rat liver nuclei. Binding of the antibodies to the unfolded form of nucleofilaments in 5 mM NaC1 and to the folded form in 80 mM NaC1 Was compared. Sucrose density gradient analyses clearly show that the antibodies can preferentially bind to nucleofilaments in 5 mM NaC1 but not in 80 mM NaC1. The antibodies, however, can bind to mononucleosomes in 80 mM NaC1. These results suggest that antigenic determinants of histone H1 in unfolded nucleofilaments and in mononucleosomes are accessible to the antibodies, while those in folded nucleofilaments are not. This is consistent with the view that histone H1 is used for folding and packing of a nucleosomal chain.


DNA polymerase beta from brain neurons is a repair enzyme. DNA polymerase beta was isolated from rat cortex neurons and characterised. Its properties were strikingly similar to those of other mammalian beta-polymerases. In adult rats, this was the major DNA polymerase occurring in neuronal nuclei, which contained no alpha-polymerase, 99.2% beta-polymerase and only 0.8% gamma-polymerase. Isolated neuronal nuclei of this developmental stage were shown to perform ultraviolet-induced repair DNA synthesis in vitro. Since beta-polymerase was virtually the exclusive DNA polymerase in these nuclei it was concluded that the beta enzyme was responsible for the observed DNA repair. This was further substantiated by demonstrating a virtually complete suppression of DNA repair in irradiated nuclei by 2',3'-dideoxyribosylthymine 5'-triphosphate (d2TTP), a potent beta-polymerase inhibitor. However, the presence of minute amounts of gamma-polymerase in neuronal nuclei and its susceptibility to d2TTP did not allow one to rule out an ancillary role of DNA polymerase gamma in DNA repair. In view of the similarity of the neuronal DNA polymerase beta with all other mammalian beta-polymerases it may be speculated that the ability to perform repair DNA synthesis is not unique to the neuronal enzyme but is a general function of all beta-polymerases.


The effect of octanoate and palmitate on the metabolism of valine in perfused hindquarter of rat. The effect of octanoate and palmitate on the oxidation of 14C-labelled valine has been studied in perfused hindquarter of rat. 1. The oxidation rate of valine increases 30 times when the concentration of valine is increased from 0.1 mM to 5 mM. 2. Octanoate at a 5 mM concentration effected a 10-fold increase in the flux through the alpha-ketoisovalerate dehydrogenase step and a 5-fold increase at 0.5 mM concentration. 3. Palmitate (1 mM) effects only a moderate increase in the valine oxidation. 4. With no octanoate there was a great accumulation of alpha-ketoisovalerate in both the muscle and the perfusion medium. 5. With octanoate little alpha-ketoisovalerate accumulated whereas 3-hydroxyisobutyrate was found in high concentration both in the muscle and in the medium. 6. Octanoate stimulated the production of citric-acid-cycle intermediates and lactate. 7. The results are discussed in relation to valine metabolism in the body.


The excision of N-methyl-N-nitrosourea-induced lesions from the DNA of Chinese hamster cells as measured by the loss of sites sensitive to an enzyme extract that excises 3-methylpurines but not O6-methylguanine. An enzyme extract from Micrococcus luteus excises 3-methyladenine and 3-methylguanine but not O6-methylguanine, 7-methylguanine, 1-methyladenine or 7-methyladenine from DNA reacted with N-methyl-N-nitrosourea. The extract was used to detect lesions in the DNA of Chinese hamster cells treated in culture with N-methyl-N-nitrosourea. It was concluded that 3-methyladenine is excised from these cells with a half-life of about 2.3 h.


Polymerization of the bacterial elongation factor for protein synthesis, EF-Tu. The bacterial elongation factor for protein synthesis, EF-Tu, polymerizes into fibrils at pH 6.0. These fibrils are 0.7 microM in diameter, at least 200 microns in length, and are positively birefringent. Electron microscopic observations of negatively stained images demonstrates that the EF-Tu fibrils consist of bundles of individual filaments, approximately 5nm in diameter, aligned parallel to the long axis of the fibril. Polymerized EF-Tu exchanges nucleotide rapidly and interacts with the other elongation factor, EF-Ts. The antibiotic kirromycin induces the polymerization of EF-Tu into fibrils and even larger structures under nonpolymerizing conditions.


Monomer-micelle transition of the ganglioside GM1 and the hydrolysis by Clostridium perfringens neuraminidase. The action of Clostridium perfringens neuraminidase on the ganglioside Gm1 tritiated in the ceramide moiety was studied. The rates of hydrolysis of the Gm1 ganglioside were determined from radioactivity in the neutral glycolipid product, which was separated from the substrate on DEAE-Sephadex columns. In order to study the physical state of the substrate in the conditions used in the neuraminidase treatment, the critical micelle concentrations of the Gm1 ganglioside were determined using formation of the triiodide anion in aqueous iodine solution as an indicator. The critical micelle concentrations were also obtained by determining the non-sedimenting radioactivity at different concentrations of the labeled ganglioside per total volume used in ultracentrifugation experiments. In addition, the concentrations of the monomeric ganglioside were concluded from the results of the ultra-centrifugation studies. The increase in the reaction rate of the Gm1 hydrolysis as the function of the substrate concentration was leveled off at 25-28 microM ganglioside. The abrupt change at this concentration is interpreted as reflecting the monomer-micelle transition of the ganglioside in the conditions used (50mM sodium acetate buffer, pH 4.6). The critical micelle concentration was 29 microM on the basis of the triiodide test, and ultracentrifugation revealed the critical micelle concentration 28 microM. The reaction velocity of the hydrolysis was decreased immediately above the critical micelle concentration, and became constant at higher concentrations of the ganglioside. A close correlation to these changes in the reaction rate is suggested to exist in the concentrations of the monomeric Gm1 ganglioside. Saturation of the buffer used in the neuraminidase assays with butanol effected a striking change in the plot of reaction rate versus ganglioside concentration. The reaction rate increased up to 100-110 microM Gm1 ganglioside. The shift of the inflexion point in the rate plot from 25-28 microM to 100-110 microM ganglioside concentration is suggested to be due to a respective change in the critical micelle concentration effected by butanol. N-Acetylneuraminyllactosyl ceramide, lactosyl ceramide and asialo-Gm1 ganglioside had an inhibitory effect on the reaction. In contrast, N-acetylneuraminyllactose, lactose and some other free saccharides were not inhibitory. The results demonstrate that factors other than the saccharide structure must be taken into account when substrate specificity of a glycosidase is studied using competition experiments. It is suggested that the inhibition effected by the glycolipids is due to an increase in the micellar state of the Gm1 ganglioside.


Enzyme memory. Effect of glucose 6-phosphate and temperature on the molecular transition of wheat-germ hexokinase LI. A theory is presented that associates burst (orlag) kinetics with the respective concentrations of enzyme initial states X1 and X6 and with the cooperation of a mnemonical enzyme. The theory predicts that for an enzyme with a negative cooperation, decreasing the initial concentration of X1 (or increasing that of X6) tends to increase the induction time. This increase may correspond to a reversal of a burst in a lag. Similarly, if the enzyme has a positive cooperation, decreasing the initial concentration of X6 (or increasing that of X1) increases the induction time. The first case above is expected to apply to wheat germ hexokinase LI, X1 being the form that binds glucose preferentially, and X6 the one that binds glucose 6-phosphate. By changing solely the respective concentrations of the two initial forms, one may expect to modify the pre-steady-state phase but not the steady-state kinetics of the reaction. By jumping the temperature of the enzyme solution from 4 degrees C to 30 degrees C and letting the transconformation ewuilibrium relax for various periods of time before mixing enzyme with the substrates, one can analyse the effect of the relative concentrations of X1 and X6 on the induction time. One can estimate in that way one of the rate constants of the transconformation between the two free enzyme forms. The shorter the incubation time at 30 degrees C then the smaller is the negative induction time (in absolute values). Another possibility of controlling the ratio between the two initial concentrations of the enzyme, is to pre-mix hexokinase with glucose 6-phosphate and to arrange that glucose-6-phosphate concentration, after mixing enzyme and substrates, is held constant whatever the pre-mixing conditions. When wheat germ hexokinase LI is pre-mixed 30 min at 30 degrees C with glucose 6-phosphate before the reaction starts, the burst does not disappear. If, on the other hand, pre-mixing is effected at 4 degrees C the burst is reversed into lag. This result is taken to mean that the equilibrium constant between the two free enzyme forms (the 'circle' and the 'rhombus') is strongly dependent on temperature. A direct study of the effect of glucose 6-phosphate on the conformational equilibrium of wheat germ hexokinase, gives support to this interpretation. If hexokinase is mixed at 4 degrees C with glucose 6-phosphate a slow increase in fluorescence of tryptophanyl residues is observed, which indicates that the 'rhombus' conformation accumulates under these conditions. On the other hand, at 30 degrees C, glucose 6-phosphate does not produce any significant change in the fluorescence of the protein. As expected, these results imply that the equilibrium between the two free enzymes species is freely reversible a 4 degrees C and nearly irreversible at 30 degrees C. The equations derived from the mnemonical model allow fitting or simulation of the experimental results.


Higher-order structures of chromatin in solution. Neutron scatter studies have been made on gently prepared chicken erythrocyte chromatin over a range of ionic strength. At low ionic strength the mass per unit length of the '10 nm nucleofilament corresponds to one nucleosome per 8--12 nm and a DNA packing ratio of between 6 and 9. From the contrast dependence of the cross-section radius of gyration of the nucleofilament the following parameters have been obtained; RgDNA' the cross-section radius of gyration (Rg) when DNA dominates the scatter; RgP, the cross-section Rg when protein dominates the scatter; Rc, the cross-section Rg at infinite contrast and alpha, the constant which describes the dependence of the cross-section Rg on contrast variation. From our understanding of the structure of the core particle, various arrangement of core particles in the nucleofilament have been tested. In models consistent with the above parameters the core particles are arranged edge-to-edge or with the faces of the core particles inclined to within 20 degrees to the axis of the nucleofilament. With increase of ionic strength the transition to the second-order chromatin structure has been followed. This gave the interesting result that above 20 microM NaCL or 0.4 mM MgCL2 the cross-section Rg increases abruptly to about 9 nm with a packing ratio of 0.2 nucleosome/mn and with further increase of ionic strength the Rg increases to 9.5 nm while the packing ratio increases threefold to 0.6 nucleosome/nm. This suggests a family of supercoils of nucleosomes which contract with increasing ionic strength. In its most contracted form the diameter of the hydrated supercoil has been found from the radial distribution function to be 34 nm. Models for the arrangements of core particles in the 34-nm supercoil are discussed.


The mode of inhibitory action by aphidicolin on eukaryotic DNA polymerase alpha. The mode of action by aphidicolin on DNA polymerase alpha from the nuclear fraction of sea-urchin blastulae was studied. The inhibition of DNA polymerase alpha by aphidicolin was uncompetive with activated DNA and competitive with the four deoxynucleoside triphosphates using activated DNA as a template-primer. For truncated (residual or limited) DNA synthesis with only three deoxynucleoside triphosphates, aphidicolin inhibited the residual synthesis more strongly in the absence of dCTP than in the absence of each of the other three deoxynucleoside triphosphates. The inhibition was reversed with excess dCTP but not with the other three deoxynucleoside triphosphates. That is, aphidicolin inhibited DNA polymerase alpha by competing with dCTP with a Ki value of 0.5 microgram/ml and by not competing with the other three deoxynucleoside triphosphates. dTMP incorporation with the activated DNA was more sensitive to aphidicolin than dGMP or dTMP incorporation with poly(dC). (dG)12-18 or poly(dA) . (dT)12-18. Similar results were obtained for DNA polymerase alpha (B form) from mouse myeloma MOPC 104E.