Mechanism of sex determination inRumex hastatulus Baldw.

Summary The results presented indicate that the sex determination mechanism in the Texas race ofR. hastatulus 2n = 10 (XX + 8A); 2n = 10 (XX + 8A)] is intermediate between theX/Y andX/A systems. In this race, sex is determined to some extent by theX/A balance, but theY chromosome also affects sex expression, maleness or intersexuality being correlated with different ratios ofX andY chromosomes.The results obtained for the Texas race are fully compatible with data presented by Smith (1963) for the North Carolina race [ 2n = 8 (XX + 6A); 2n = 9 (XX ₁ Y ₂ + 6A)]. It may be concluded that evolution of the karyotype in this species is not accompanied by changes in the mechanism of sex determination.     

Visualization of the cytoskeleton in Leydig cells in vitro

Summary Effect of LH, vinblastine and cytochalasin B on the cytoskeleton of cultured Leydig cells was investigated using monoclonal antibodies and fluorescence microscopy. After LH addition and treatment with cytoskeletal disrupting drugs, three main effects were observed: 1) increase of androgen level secreted by cultured mouse Leydig cells, 2) changes of cell-shape towards regular and rounded, 3) increase of ⁵,3-HSD activity. The results are discussed in respect to possible involvement of cytoskeleton in the regulation of steroidogenesis.     

Ultrasonographic and scintigraphic studies of "hot" autonomic thyroid nodules

Scintigraphic and gammagraphic (gamma-camera) techniques have been applied in diagnosing "hot" non-TSH dependent thyroid nodules. On the basis of frequent uneven accumulation of isotopic tracer observed in scintigraphic studies it was concluded that the structure of these nodules is heterogeneous. In some cases paradoxical patterns have been obtained following the dynamic tests of suppression and stimulation of the thyroid: after the administration of thyroid preparations paranodular thyroid tissue appears, while TSH administration causes an increase in the iodine uptake by the nodule. Ultrasonographic and gamma-camera studies have been carried out in 50 cases of "hot" autonomic thyroid nodules previously diagnosed by scintigraphy. Ultrasonographic studies revealed a weaker echogenicity in some cases and an intensified echo in the other. Sometimes by using this technique it was possible to demonstrate the occurrence of heterogeneous structures suggesting a cystic degeneration of the nodule. Paranodular thyroid tissue, invisible in scintigraphic scanning, could usually be observed by applying gamma-camera. It was concluded that both gamma camera and ultrasonographic studies confirm heterogeneous structure of intranodular tissue producing paradoxical patterns in scintigraphic scanning, with the latter technique usually aiding the detection of paranodular thyroid tissue without the necessity of application of the TSH test.     

Certain aspects of so-called post cholecystectomy syndrome

The study involved 126 patients with cholelithiasis. Set of biochemical, radiological, endoscopic, and ultrasound examinations was carried out in these patients. Potential coincidence of clinical symptoms and causes of so-called postcholecystectomy syndrome was the purpose of a 1-year follow-up studies. The significance of the results are discussed.     

Monotherapy with acebutolol in hypertensive diabetic patients

Monotherapy of hypertension with acebutolol in diabetics in daily dose of 200-400 mg for 6 weeks induced only non-significant and practically not acceptable hypotensive effect in groups of patients with hypertension and diabetes type I or type II without nephropathy. No therapeutical effect was observed in hypertension in diabetics type I with nephropathy. Administration of acebutolol to hypertensive diabetic patients with nephropathy resulted in tendency to increase in albuminuria. Values of creatinine clearance did not change at the same time. Also no effect of acebutolol on glycemic or lipid indices was observed. The lack of clear hypotensive effect under studied conditions of acebutolol in diabetic patients contrasted with its significant action in comparative group of hypertensive non-diabetic subjects.