[Experimental evidence of magnesium salts for treatment of calcium oxalate nephrolithiasis in an animal model based on sodium oxalate and a cyclooxygenase 2 selective inhibitor].

The purpose of present study was to investigate influence of magnesium (Mg) salts (Mg L-aspartate, Mg chloride) and their combinations with pyridoxine on development of calcium-oxalate nephrolithiasis induced by sodium oxalate (3% diet weight) and celecoxib (100 mg per kg of bodyweight) according to B.C. Jeong et al. (Urol. Res. 2005; 33(6): 453-459). On 14th day of diet urinary oxalate level and crystalluria were significantly increased, creatinine clearance tended to be lower as compared to control group. Mg L-aspartate, Mg chloride and their combinations with pyridoxine, MagneB6 (Mg lactate in combination with pyridoxine) and Mg sulfate were given by intragastric intubation from 15th till 28th days of diet (50 mg Mg per kg body weight). On 28th day urinary oxalate level in rats treated with Mg salts was lower by in average 45%, creatinine clearance was increased by 19%, Ca/Mg ratio decreased by 1.5-2 times in comparison with animals fed with diet alone. Light microscopic examination of kidney sections have revealed decreased inclusion volume fraction of renal calcification in rats treated with Mg salts as to compare with untreated rats receiving sodium oxalate and celecoxib (0.3-1.0% vs. 4%). So, Mg salts prevented development of calcium-oxalate nephrolithiasis in hyperoxaluric rats. Morphological and laboratory tests showed Mg aspartate and magne B6 were more effective Mg-containing substances in comparison with other studied salts.

[The effectiveness of certain magnesium salts in nephrolithiasis caused by the use of sodium oxalate and celecoxib].

The study was aimed to evaluation the effect of different magnesium salts and their combinations with pyridoxine on a course of calcium-oxalate nephrolithiasis, which was modeled by adding the sodium oxalate (3% of weight of the diet) and selective cyclooxygenase-2 inhibitor celecoxib at a dose 100 mg/kg body weight to a diet for 4 weeks. Starting from the 2nd week of the experiment, the animals had received one of the following compounds: magnesium L-aspartate, magnesium chloride, and their combination with vitamin B6; magnesium sulfate and Magne B6 (magnesium lactate and vitamin B6) as comparators. 28 days after the start of the experiment, disorders progressed in the group receiving only celecoxib and oxalate-rich diet: the urine level of oxalate increased by 171% (p < 0,0001), crystalluria had increased (up to 105 crystals in 10 microml of urinary sediment, p < 0,0001), creatinine clearance decreased by 29%, compared to control (p = 0,087). Increasing calcium/magnesium and oxalate/creatinine ratios in urine by 16 and 189%, respectively, was observed. In the renal parenchyma of animals treated with sodium oxalate and celebrex, calcifications with a volume fraction of 4% were identified, whereas these changes were absent in intact animals. According to the degree of correction ofhyperoxaluria and elimination of calcium oxalate crystals, investigated salts showed similar efficacy, with the exception of magnesium sulfate, which less contributed the compensation of abnormalities in kidney and urinary. According to the data of morphological study, the volume fraction of calcifications was lowest in the groups receiving magnesium L-aspartate and Magne B6.

Mechanisms of toxic effect of streptozotocin on ß-cells in the islets of langerhans.

Administration of streptozotocin caused selective damage to endocrine ß-cells in rat pancreatic islets, which was related to activation of apoptosis. The cytotoxic effect of streptozotocin was associated not only with DMA damage due to dysfunction of the antioxidant defense system, but also with activation of the caspase cascade and TNF-related apoptosis-inducing ligand.

[Structural alterations in pancreatic islets in streptozotocin-induced diabetic rats treated with of bioactive additive on the basis of Gymnema sylvestre].

The structural alterations in pancreatic islets in streptozotocin-induced diabetic rats were studied after the administration of Gymnema sylvestre extract or its composition. Diabetes mellitus was modeled by daily injection of streptozotocin (20 mg/kg for 5 days) and single injection of 0.2 ml of complete Freund's adjuvant, Only the animals with the blood glucose level exceeding 15 mmol/l were included in the experiment. B- and A-endocrinocytes were demonstrated using immunocytochemistry. The proportions of the area of the pancreatic islets, occupied by B- and A-endocrinocytes, as well as the volume fraction of the pancreatic islets within the pancreas, were determined. In the model of streptozotocin-induced diabetes, the part of the total islet area occupied by B-endocrinocytes, was diminished in the pancreatic islets located in all the zones of the gland. Prophylactic administration of Gymnema sylvestre extract or its composition tended to restore the area occupied by B-endocrinocytes in the pancreatic islets. These results indicate the equal potency of the composition and extract of Gymnema sylvestre to induce the regeneration of B-endocrinocytes.

[Prevalence of different histological types of brain tumors in the volgograd region according to the data of intraoperative biopsies over the period of 2001 to 2006].

The prevalence of different histological types of brain tumors was analyzed in the Volgograd Region from the data of intraoperative biopsies over the period of 2001 to 2006. Gliomas were a dominant group (51.9%) at all study time intervals. Among them, there was a preponderance of glioblastomas (24.7%), anaplastic astrocytomas (21.1%), protoplasmatic astrocytomas (15.4%). The fact that heterogenic tumor tissue in a great deal of the study cases of malignant gliomas makes pathohistologists' opinion differ and suggests that there is a need for an in-depth study of intraoperative biopsy specimens, by using the existing antibody panels and developing new ones for immunohistochemical studies.

[The morphofunctional state of the blood-brain barrier at the level of the medulla oblongata in experimental West Nile encephalitis].

Pronounced clinical and morphological changes were found in the neurons and microcirculatory bed (MCB) vessels at the level of the medulla oblongata in experimental West Nile encephalitis (WNE). At the same time, the magnitude of changes in MCB vessels and nerve cells in the cores of the medulla oblongata correlated with the state of the surrounding astrocytic glia. It is suggested that the intensive astroglial reaction revealed during this experimental WNE reproduction promotes the prevention of neuronal lesion.

[Morphological changes in the murine medulla during experimental West Nile virus (strain 986) infection].

The trends in antigen expression and structural changes in the medulla of albino mice infected by West Nile virus (WNV) were studied in different periods of an infectious process, by using monoclonal antibodies to WNV. The maximum amount of immunoreactive material was found in the damaged neurons of dead animals, although WNV antigen expression in the perikaryonic cytoplasm of individual neurons was observed in all the experimental groups. Small amount of neuronal immunoreactive material and its significant levels in the glial cells of symptomatic animals are regarded as a manifestation of individual differences in the neuronal microelement.

Ultrastructural changes in the lateral reticular nucleus of the medulla oblongata in prepubertal rats under the effect of long-term stress exposure.

Ultrastructural changes in the lateral reticular nuclei of the medulla oblongata of rat pups developing under the effect of chronic mental and pain stress indicate impaired histogenesis of structures of the medulla oblongata reticular formation and appearance of pronounced morphofunctional differences between the neurons.

Variability of neuronal damage and proportion of activities of NO synthase isoforms during cerebral ischemia/reperfusion in rats.

We studied expression of endothelial and neuronal NO synthase isoforms and severity of ischemia/reperfusion-induced damage to neurons in different brain compartments in albino rats. The peculiarities of distribution of NO synthase isoforms in the cerebral cortex and medulla oblongata were determined by different sensitivity of these compartments to ischemic and reperfusion damage to neurons.

Ultrastructure of neurons in the hypothalamic suprachiasmatic nucleus of rats with different stress reactivity.

The rats were divided into groups demonstrating extremely high and low stress reactivity depending on the results of testing for the nociceptive threshold and thermolability in response to bacterial lipopolysaccharide administration. Specific structural features of the nucleus and mitochondria were revealed in neurons of the hypothalamic suprachiasmatic nucleus in rats with constitutionally high reactivity, which reflects high functional activity and stress-induced lability of these structures. Ultramicroscopic study revealed phenotypic differences in one of the key hypothalamic nucleus, which enables potent and rapid neurogenic response of the stress system in animals with high stress reactivity.

[Changes in myocardium, skeletal muscle and liver of rats fed carnitine-deficient diet and treated with carnitine optical isomers].

The aim of the present study was a comparative assessment of L-, D-and DL-carnitine effect on morphometric and histological parameters of myocardium, skeletal muscles (m. gastrocnemius) and liver in 60 rats fed carnitine-deficient diet. Carnitine-deficient diet fed 2 months resulted in a substantial reduction of carnitine concentration in blood plasma of rats. In carnitine-deficient animals, lipid vacuoles were found to accumulate within the hepatocytes in all the zones of hepatic lobules, which mainly had the character of micro- and macrovesicular steatosis. This was accompanied by a reduction of skeletal muscle fiber and cardiomyocyte average thickness. L-carnitine administration resulted in the compensation of carnitine deficiency in animals with alimentary carnitine deficient state, while the racemate and D-stereoisomere did not affect its content in blood. Pharmacological correction of carnitine deficiency with L-carnitine prevented the development of liver fatty dystrophy to a greater degree, than the administration of other carnitine stereoisomeres and promoted the restoration of muscular fiber thickness of skeletal muscles. DL-carnitine administration was accompanied by a moderate correction of fatty dystrophy and did not prevent the development of skeletal muscles atrophy. D-carnitine stereoisomere did not prevent liver fatty dystrophy, but it reduced its severity. Correction of carnitine deficiency with D- stereoisomere was not accompanied by essential morphological and morphometric differences in degree of skeletal muscle atrophy.

[Astrocytic morphological responses in different murine brain regions in the simulation of West Nile fever].

The brains from the mice infected intraperitoneally (with development of these or those symptoms of viral encephalitis) or intramuscularly with the Astrakhan West Nile fever virus strain (AcT 986) was pathomorphologically studied. Clinicomorphological changes in the neurons and vessels of the microcirculatory bed were found in the dorsal regions of medulla oblongata. Immunohistochemicall analysis showed that mature and/or activated astrocytes increased in number, largely in the animals without clinical manifestations of encephalitis. The findings provide evidence that cerebral astrocytes play a protective and adaptive role that seems to depend on the biological properties of the pathogen.

Structural changes in the nucleus ambiguus of the medulla oblongata and intracardiac ganglia in growing rats in immobilization stress.

The aim of the present work was to study qualitative and quantitative measures of histological changes in the nucleus ambiguus (NA) of the medulla oblongata and the cardiac autonomic ganglia (CAG) in growing animals in conditions of immobilization stress of different durations. Experiments were performed on 56 mongrel white rats aged 30 days. Immobilization stress was produced by placing rats in a special apparatus with a controllable internal volume for 3, 7, 15, and 30 days. The NA and CAG were studied on paraffin sections using neurohistological methods and quantitative analysis. Morphological and morphometric changes, consisting of a delay in the growth of neurocyte cell and nucleus volumes, as compared with controls, were seen both in the NA of the medulla oblongata and the CAG and were evaluated as impairments in the histogenesis of nerve tissue during postnatal ontogenesis. The extent of structural changes in these components of the autonomous nervous system was directly dependent on the duration of the experimental treatment.

Effects of L-, D-, and DL-carnitine on morphometric parameters of skeletal muscle and exercise performance of laboratory animals receiving carnitine-deficient diet.

Serum concentration of L-carnitine, the mean thickness of the skeletal muscle fiber, and exercise performance in the forced swimming test decreased in rats receiving a carnitine-deficient diet. Treatment with L-carnitine compensated for carnitine deficiency, while racemate and D-stereoisomer did not increase its level. L-Carnitine, but not racemate and D-stereoisomer, promoted recovery of the skeletal muscle fiber thickness and exercise performance of rats.

Ultrastructural changes in neurons of medullary giant-cell nucleus in growing rat exposed to acute stress.

Ultrastructural transformations in neurons of the medullary giant-cell reticular nucleus of young rats during exposure to acute emotional and painful stress attest to activation of the protein synthesis system (nucleolar hypertrophy, well-developed elements of the granular endoplasmic reticulum, increased content of free ribosomes and polysomes) in the majority of cells and the appearance of organelle injuries in some these cells.

[Structural changes in the medullary nucleus ambiguus and cardiac autonomic ganglia of growing rats under influence of the immobilization stress].

The objective of this study was to evaluate the quantitative and qualitative histological changes in the medullary nucleus ambiguus (NA) and cardiac autonomic ganglia (CAG) of the growing organism under the influence of immobilization stress of different duration. The experiments were performed on 56 outbred albino rats with the initial age of 30 days. Immobilization stress was induced by placing the rats into special chambers with a controllable volume of the inner space for 3, 7, 15 and 30 days. NA and CAG were studied on paraffin sections using the neurohistological methods and a quantitative analysis. Morphological and morphometric changes have demonstrated the retardation of the growth of neurocyte cell bodies and of their nuclei both in medullary NA and CAG as compared to those in control animals, which are regarded as an indication of a disturbance of the histogenesis of the nervous tissue in postnatal development. The degree of structural changes of the components of autonomic nervous system studied was directly related to the duration of experimental exposure to immobilization stress.

[Morphological and immunohistochemical changes in tissues of the lung, myocardium and kidney in experimental West Nile fever].

An experimental infection of mice with West Nile virus (WNV) showed pronounced dystrophic changes in tissues of the kidneys and myocardium as well as expression of WNV antigens in cells of the lungs, kidneys and myocardium, which can denote tropism of WNV to tissues of the lungs, kidneys and myocardium.

[Hepatotropic action of the virus of West Nile fever].

An experimental infection of mice with West Nile Virus (WNFV) showed pronounced dystrophic changes in the hepatic parenchyma and expression of WNV antigens in the endothelium of hepatic capillaries and in hepatocyte cytoplasm, which testifies to the tropic action of WNFV to hepatic tissue.

[Pathomorphology of West Nile fever]. / Patomorfologiia likhoradki zapadnogo Nila.

8 patients, aged from 61 to 70 years, died from serous meningoencephalitis during the outburst of the West Nile fever in Volgograd in 1999-2001, were studied morphologically. Serous meningoencephalitis with necrotic vasculitis is a characteristic feature of this fever with degenerative changes and destructive foci in the brain. Proteinic and fatty inflammatory and lymphomacrophageal reactions were observed in the liver, serous productive myocarditis and cardiomyocytic necrosis dystrophy. Desquamative pneumonia, intracapillary nephritis were also seen. Immunohistochemical reaction against virus of this fever was positive in the vascular endothelium of parenchymal organs, hepatocytes, neurons of the brain.

Morphofunctional characteristics of antigen-presenting cells in lymph node in mice with experimental West Nile fever.

Pronounced transformation of cells in mesenteric lymph nodes, mainly in the thymus-independent zone and sinuses, was detected in albino mice experimentally infected with West Nile fever (strain 986). Maximum antigen-presenting activity was exhibited by activated macrophages, minimum activity--by dendritic cells of lymphoid follicles.