Hippocampal capillaries in different age groups of chronically ethanol-intoxicated rats. Morphometrical studies.

The influence of chronic ethanol intoxication on the terminal vascularization of particular hippocampal fields and layers was investigated in different age groups of rats. Thirty-six male Wistar rats aged 6 weeks were used in the study. For twelve months 24 of them drank only 25% ethanol--12 starting at 6-week-age and 12 at 3-month-age.

Interstitial tissue fraction. The prognostic marker in membranoproliferative glomerulonephritis in children.

Objective: To explain the differences in the clinical course of membranoproliferative glomerulonephritis (MPGN) in children and to find some prognostic markers at the disease onset that correlate with the disease outcome.

Study Design: We reviewed clinical histories and laboratory findings, reexamined kidney biopsies performed at the disease onset and evaluated volume relations between kidney components in children with the diagnosis of MPGN.

Results: Children were divided into three groups based on their final clinical status: I.

Effects of vitamin D on aortic smooth muscle cells in culture.

Earlier investigations on vitamin-induced experimental atherosclerosis in rats suggested that smooth muscle cells (SMCs) play a pivotal role in development of these vascular abnormalities. This study demonstrates the effects of vitamin D (ergocalciferol) on SMCs of rat aorta in tissue culture. SMCs were obtained from aortas of newborn rats by enzymatic digestion and maintained for 6 wk in primary culture with vitamin D (1.

Pericapillary and distant axon terminals in the nuclei of the cat amygdala: a morphometric study.

According to some ultrastructural studies, the pericapillary axon terminals in the central nervous system (CNS) are functionally connected with the capillary vessel wall. Thus, it may be expected that the population of pericapillary axon terminals will be morphologically distinct from the terminals at a further distance from the capillary walls. To test this hypothesis, morphometrical analysis of 3,048 axon terminals was performed, comparing terminals situated in the close vicinity of the capillary vessel with those at a distance from the vessels in the lateral, basal, medial, central and cortical nuclei of the amygdaloid body of eight cats.

Pathogenesis of heart myofibril lesion in experimental vitamin D-induced cardionecrosis.

Multifocal cardionecrosis has been produced in rats by treatment with 3 x 100,000 iu vitamin D3 (calciol). The effects of hypervitaminosis D on rat heart myofibril structure and total protease activity was investigated. Proteolytic enzyme activity of heart muscle homogenate was determined in two independent ways, and was approximately two times higher in the necrotic heart homogenate than in the control rat heart.

Comparative morphometric analysis of terminal vascularization of hippocampal CA1 and CA3 sectors in Mongolian gerbils.

Comparative morphometric analysis of terminal vascularization (vessels with a diameter lower than 12.5 microns) in the ischemia-sensitive sector CA1 and the ischemia-resistant sector CA3 of Ammon's horn in Mongolian gerbils was performed. Basing on numerous computer-counted parameters characterizing the terminal vascular network in both hippocampal sectors and its relationship to the surrounding tissue, it was shown that a number of capillary vessels, their average diameter, and exchange and flow surfaces were to a statistically significant degree lower in the pyramidal layer of the CA1 sector as compared with those in CA3 sector.

Terminal vessels of dentate gyrus in chronically alcohol-intoxicated rats.

Quantitative changes in the microvasculature of the central nervous system of the rat following chronic ethanol intoxication were studied. For 6 months, 12 rats drank only 25% ethanol and eight control rats only water. After fixation by perfusion, semithin sections of dentate gyrus were obtained.

Hepatitis B virus-associated glomerulonephritis: electron microscopic studies in 98 children.

Ninety-eight children with glomerulonephritis concomitant with hepatitis B surface HBs antigenemia were studied, the antigenemia being first documented at the clinical onset of glomerulopathy. Initial diagnoses, based on examination of the paraffin sections, varied, membrano-proliferative, mesangial, and membranous glomerulonephritis being most frequently considered. However, electron microscopic examination showed that 77 children had a uniform type of glomerulopathy, irrespective of the light microscopic appearance.

Calcium content of serum and myocardium in vitamin D-induced cardionecrosis.

The dynamics of calcium content alterations in serum and heart muscle in relation to vitamin D-induced cardionecrosis was the aim of the experiment performed on female Wistar rats killed at different times after one or two intraoral doses of 100,000 IU of vitamin D. Calcium concentration in the serum showed great individual variability, although the mean value was significantly elevated after 22 h following one dose and after 2 h following two doses of vitamin D. In the heart muscle the mean calcium content increased 72 h after one dose and 24 h after two doses of 100,000 IU of calciol, but in individual rats the increase of Ca concentration was observed as early as 30 h after one dose, in some it was normal even after 144 h of two doses and varied between individual rats 20-30-fold.

Effects of ethanol on the development of experimental atherosclerosis and cardionecrosis in rats.

The influence of chronic ethanol intoxication upon vitamin D-induced damage of cardiovascular system in rats was examined. Eighty rats, divided into 16 groups according to sex and age, were intoxicated with ethanol as the only source of liquid. Control rats drank water only.

Pathology and ultrastructural characteristics of a hypomelanotic variant of transplantable hamster melanoma with elevated tyrosinase activity.

A spontaneous, hypomelanotic variant (MI) of the highly melanotic transplantable hamster melanoma of Bomirski (Ma) is the subject of this report. Tyrosinase activity is 2-3 times higher, but melanin content significantly lower than in the parental Ma melanotic melanoma. Acid phosphatase activity is similar in both, but beta-glucuronidase and aryl-sulfatase A are 2-3 times higher in the hypomelanotic variant.

Henoch-Schönlein nephritis in children--a clinicopathological study.

36 children with Henoch-Schönlein nephritis had their renal biopsy specimens studied by light and electron microscopic and immunofluorescence antibody techniques. Though no pathognomic changes were found the histological picture was characteristic. The severity of histological changes correlated well with the clinical manifestation and disease persistence.

The respiration and calcium content of heart mitochondria from rats with vitamin D-induced cardionecrosis.

Mitochondria were isolated from the heart and skeletal muscle of rats treated with three consecutive daily doses of 100 000 i.u. of calciol (cholecalciferol; 'vitamin D3').

Mesangial proliferative glomerulonephritis in children.

Over a ten year period 105 children with a histological diagnosis of a mesangial proliferative glomerulonephritis were diagnosed. Patients were divided into two groups according to their clinical presentation at the time of diagnosis. Ninety two children presented with nephrotic syndrome (NS) of whom 82 received steroid therapy.

Ultrastructure of vascular and connective tissue changes in primary syphilis.

Electron microscopical studies of primary syphilitic lesions showed intensive changes in the capillaries in the form of endothelial proliferation and extensive infilitration of different cells in the surrounding connective tissue. The degenerative changes in axon terminals could explain the painless course of primary induration.