Acta medica Academiae Scientiarum Hungaricae最新文献

An increased secretion of gonadotropic hormone was found in hyperthyroid males despite the high basal serum total testosterone and oestradiol levels. This suggests that hyperthyroidism affects the responsiveness of the hypothalamic-pituitary axis to sexual steroid hormones. While in the hyperthyroid patients the elevation of the serum testosterone level in response to chorionic gonadotropin was lower than normally, the LH and FSH responses to LRH were increased. The results indicate that male hyperthyroidism is associated with a loss of responsiveness of the Leydig-cells to adequate stimuli, to which the pituitary reacts by a compensatory increase in its LH-secretion and by an increased reactivity to LRH. It is suggested that in addition to the direct effect of the increased thyroid hormone levels, a secondary elevation of the oestradiol concentration plays a major part in the alterations in question.

Cytotoxic activity and progesterone binding capacity of lymphocytes obtained from 135 pregnant women was tested. Cytotoxic activity of healthy pregnant women's lymphocytes was significantly lower (p less than 0.001), while progesterone binding capacity significantly higher (p less than 0.001), than those of lymphocytes obtained from women with threatened abortion or threatened premature labour. Neither cytotoxic activity nor progesterone binding capacity of the lymphocytes was influenced by gestational age. Furthermore, the number of previous pregnancies did not have any effect on either of the two parameters.

Intravenous infusion of bombesin (0.9 micrograms/kg/hour) caused a significant increase in gastric acid secretion and serum gastrin concentration in 8 duodenal ulcer patients. Intravenous infusion of calcitonin (2 MRCU/kg/hour) produced a significant decrease in gastric acid output and in integrated gastrin output produced by bombesin infusion (0.9 micrograms/kg/hour) in the same 8 patients with duodenal ulcer. Percentage of inhibition was 49.7 and 40.8, respectively. Simultaneous infusion of calcitonin and bombesin caused no significant difference in serum calcium concentration. It is suggested that the inhibitory effect of calcitonin on acid secretion elicited by bombesin is produced, at least in part, by a fall in serum gastrin caused by bombesin. In addition, calcitonin might directly inhibit the parietal cells by releasing endogenous gastric somatostatin.

Fourty-four patients with IgA-glomerulonephritis (IgA GN) were studied for circulating immune complexes (IC) repeatedly in the course of disease on the evidence of four different methods suited for the detection of IC, viz. complement consumption assay, Clq-solubility test and two tests based on PEG-precipitation, and of indirect signs pointing to the presence of IC. Joint assessment of the direct and indirect signs (positivity of a minimum of 2 indirect signs or any of the direct signs) permitted to ascertain the presence of circulating IC in 72 per cent of the patients and in 63.3 per cent of the examined sera. There was no close relationship between the presence of IC and the clinical activity. On the other hand, in 16 patients positive for the rheumatoid factor (RF) the renal biopsy material revealed extensive vascular lesions. The findings suggest that the circulating IC, some of which contain RF, play a part in the pathomechanism of IgA GN and are involved in the production of the vascular abnormalities in this disease.

The changes in body weight after jejuno-ileal bypass surgery in 23 cases of massive obesity are reported. After an initial rapid weight reduction, body weight fell at a constant rate over six months. The weight reduction curves correspond to a zero order kinetics. After the first six months the rate of weight loss declined, but the weight continued to fall. By 12 to 24 months after the operation stabilization of body weight at an average level corresponding to 38% of the preoperative weight was attained.

Lead-exposed (n = 26) and control (n = 12) subjects were investigated for their blood lead concentration erythrocyte 5-amino-laevulinic acid dehydratase (5-ALAD) and erythrocyte uroporphyrinogen-I-synthetase (URO-I-S) activity; 5-amino-laevulinic acid (5-ALA) and porphobilinogen (PBG) were used as substrates in the synthetase assay. In the lead workers erythrocyte 5-ALA dehydratase was grossly inhibited but with PBG as substrate the synthetase activity was not significantly different from the control group. With 5-ALA as substrate the synthetase assay showed marked inhibition. Addition of zinc (0.1 mmol/l) and dithiotheritol (0.5 mmol/l) brought the activities of both the dehydratase and synthetase (using 5-ALA as substrate) back into the ranges seen in the control group. With porphobilinogen as substrate higher concentrations of zinc caused inhibition of the synthetase, whilst reduction of added zinc to 0.01 mmol/l resulted in stimulation of the synthetase. A good correlation (r = 0.87) was obtained in synthetase assay when PBG and 5-aminolaevulinate (with added zinc and dithiothreitol) were used as substrates. With these additions 5-ALA may be used as a substrate in the URO-I-S assay in the investigation of latent cases of acute intermittent porphyria.

A simple rapid method for the measurement of leucocyte adherence and adherence inhibition in tubes is described. The procedure is based on determining the amount of cell protein. We compared measurement of adherent cells by protein assay with the automated counting of the non-adherent cells in the tube leucocyte adherence inhibition test. Both procedures gave quantitatively similar results and a high statistical correlation was found between them. The results suggest that the protein assay is a reliable substitute for cell counting.

The sympathetic and parasympathetic neurological cardiac effects were blocked with atropine and propranolol. The intrinsic heart rate (IHR) was determined and rapid atrial pacing (RAP) was carried out before and after administration of the drugs. The primary and secondary postpacing parameters were examined in both circumstances. Normal (n = 31) and pathological (n = 20) cases were differentiated on the basis of the IHR. In the secondary phase (PPC 2-10) after autonomic blockade returned to the basic frequency was of exponential character in the great majority of normal IHR cases. Anomalies may appear in both the primary and secondary phases. They are of different types: one of them concerns the recovery time; another electrophysiological anomaly occurs when there is no return to the predrive normal cycle length after pharmacological neurotomy. In the secondary phase there may appear sinoauricular blocks. They may depend on or appear independently of the effect of the vegetative nervous system. The new test allows a physiopathological classification of normal and pathological sinus node function.

Significant retardation in body and kidney growth and in renal glomerular and proximal tubular development was observed in hypothyroid rats in comparison with euthyroid controls. Body mass was found to increase by 40% but kidney mass only by 3.5% over a period of 3 weeks following thyroidectomy in contrast to an average increment of 178 and 113%, respectively, in normal animals. Dissociation was found also in the development of glomeruli and proximal tubules: glomerular size correlated with body weight while tubular size with kidney weight. Single nephron glomerular filtration rate was adapted not to the glomerular as normally but rather to the tubular volume thereby compensating functionally for the dimensional glomerulotubular imbalance. However, despite the decreased filtered and excreted amount of sodium relative to the body weight sodium balance was maintained by depressed tubular reabsorption which was uniformly observed in thyroid deficiency. Because of the uncertainty regarding the direct action of thyroid hormones on the tubular function it is assumed that decreased tubular sodium reabsorption is principally caused by the mechanism subserving the maintenance of sodium balance also in salt loaded normal and sodium sensitive Dahl's rats. This seems to be supported by the exaggerated natriuresis observed both in hypothyroid and sodium sensitive Dahl's rats after saline infusion. Justification of the proposed mechanism needs further investigation.

Radio-iron kinetic tests were performed in 7 patients with end-stage renal disease treated by hemodialysis; the study could be completed in 6 patients. The incorporation of radio-iron into the erythrocytes was 21% on average in patients with acute anemia. The red cell life-span determined in 4 patients became significantly shorter in 3 patients. Iron turnover in the bone marrow was significantly lower than normal, the rate of ineffective erythropoiesis being higher. Serum ferritin levels were significantly higher, and tissue and extravascular iron turnover was found to be enhanced compared to normal. At the same time, serum iron level was normal. The data on iron turnover indicated deficient hemopoiesis in the bone marrow, due partly to the lack of erythropoietin and partly to the insufficiency of the BFU-E (burst forming units) and CFU-E (colony-forming units) reserves. Undoubtedly, this was a consequence of the uremia.