Experimental Model to Study the Role of Retinoblastoma Gene Product (pRb) for Determination of Adipocyte Differentiation.

Using stable constitutive expression of retinoblastoma gene product (pRb) in polypotent mesenchymal 10T1/2 cells we obtained stable cell lines hyperexpressing functionally active or inactive mutant pRb. The cells producing active exogenous pRb demonstrated high sensitivity to adipocyte differentiation inductors, whereas production of inactive form of the exogenous protein suppressed adipocyte differentiation. The obtained lines can serve as the experimental model for studying the role of pRb in determination of adipocyte differentiation.

[Oxygen consumption in the lungs and systemic circulation--different methods of measurement of one data or different data?].

The article deals with calculation of oxygen consumption in the lungs by means of breathing gas mixture analysis and in parallel--in the systemic circulation by reverse Fick method; 32 paired measurements were performed in 8 patients after cardiac surgery with cardiopulmonary bypass. The mean pulmonary oxygen consumption was higher than the same value calculated by the reverse Fick principle--148.4 +/- 39.

Bone marrow stem cells repopulate thyroid in X-ray regeneration in mice.

The aim of this study was to clarify the regeneration mechanisms of thyroid in post-irradiated C57Bl/6 mice chimeric with transgenic green fluorescent protein (GFP) positive C57Bl/6 mice after 5 and 7.5Gy X-ray exposures with the aid of morphological and immunocytochemical research of GFP-positive cell distribution. Cryostat slides of larynxes with thyroid glands were fixed by mixture of cold methanol and ethanol, cell nuclei were stained with propidium iodide.

[Epithelial intestine cells transdifferentiate into bladder urothelium in experiments in vivo].

The autoplastic surgery by intestine tissue has been used for reconstructive therapy of the urinary tract since the middle of the last century; however, cell mechanisms of the urothelium engraftment are still obscure. Intestine stem cells possess plasticity and presumably enable after the autoplastic surgery to transdifferentiate into mature cells of urinary tract. Using the preliminary developed in vivo model for evaluation of somatic cells transdifferentiation into urothelium, we have found that the epithelial intestine cells producing Gfp transdifferentiate into the cryoinjured bladder urothelium of the syngenetic C57BL mice.

[Characteristic of tumors developed after transplantation of transgenic GFP-positive C57BL/6 mice bone-marrow mesenchymal stem cells to mdx mice muscle].

The purpose of the study was the morphological and histochemical characteristics of differentiation of tumors developed after transplantation of GFP-positive mesenchymal bone-marrow stem cells (MSC) of transgenic mice C57BL/6 into M. quadriceps femoris of mdx mice. The tumors occurred only after transplantation of MSCs of 43-45th passages and did not arise after transplantation of MSCs of the 15th passage.

[Model in vivo to study the transdifferentiation of the somatic cell into urothelium].

Development of reconstructive therapy of the urinary tract using pluripotent and somatic stem cells, for example mesenchymal stem cell (MSCs), recently goes through the stage of experimental studies. These studies include investigation of the main functions of MSCs and urothelium lining from inside the organs of the urinary tract. An important role in the regulation of proliferation and differentiation of urothelium belongs to EGF and Wnt-beta-catenin signaling pathways which activity may be accessed by the level of Her-4 and Tcf3,4, accordingly.

[Spontaneous transformation and immortalization of mesenchymal stem cells in vitro].

Mesenchymal stem cells (MXC) possess plasticity and unlimited proliferative activity in vitro that makes them an attractive subject of the studies focused on searching new resources for regenerative medicine. The usage of MSC is effective for treatment of patients with degenerative and traumatic diseases of different tissues, however, biological basis of therapeutic efficacy of MSC are still obscure. We found that long term culture of MSC expressing transgenic green fluorescence protein (GFP) led to increase in their proliferative activity, decrease in adhesion, and loss of differentiation potential and production of the GFP.

[Characterization of cultured murine mesenchymal stem cell line expressing GFP].

We have developed and characterized a murine mesenchymal stem cell line from the bone marrow of transgenic mouse C57BL ubiquitously expressing GFP. Immunostaining analysis revealed the presence of several markers typically found in fibroblasts such as smooth muscle cells actin in the form of stress fibrils and vimentin--the protein of intermediate filaments. These cells maintained capability to differentiate into adipocytes or osteoblasts under appropriate conditions.

Autoimmune regulation of genetically determined cell functions in health and disease.

Autoimmunity and its contradictory nature in autopathokinesis have drawn attention from the emergence of immunology as a science. The properties of antibodies (AB) towards nuclear antigens (AGs) of endocrine cells are both theoretically and clinically hot topics as are their applications in the modulation of genetically determined cell functions. In this review we discuss the AB production after immunization of animals with nuclear AGs, their immunospecificity and the mechanisms of their intracellular penetration and association with nuclear proteins.

[Effect of anti-histone antibodies on the nuclear apparatus of thymocytes of intact and irradiated rats].

The interaction of specific immunoglobulins G to the histone H1 with the thymocytes of intact animals has been demonstrated to increase the reception of acridine orange (AO) in nuclear chromatin. This raises the rate of AO fluorescence and lowers the level of light polarization. This may result from occurring decondensation processes.

[Status of the glucocorticoid function of the adrenal glands in patients with juvenile rheumatoid arthritis].

The authors studied the glucocorticoid function of the adrenals in 117 patients with juvenile rheumatoid arthritis (JRA) and in 37 children of the control group. Relation between the level of cortisol in the blood plasma and sex, age form and duration of the disease, indices of the clinical, laboratory and immunological activity, the nature of roentgenological changes in the joints and therapy was analysed. A decrease in the glucocorticoid function of the adrenal cortex correlated with the severity of the clinical forms and duration of the disease, being especially manifest in children of younger age.

[Laser therapy in acute nonspecific epididymo-orchitis].

Laboratory experiments were followed by clinical investigations of low-intensity laser radiation (LR) feasibility in therapy of acute epididymo-orchitis. A total of 117 patients aged 15-68 were treated with mild, moderate and severe scrotal inflammation. The response was compared to that in physiotherapy (54 patients) and early surgery (40 patients).

[Gastrin, insulin and glucagon secretion after cimetidine and sodium hydrocarbonate intake in patients with duodenal ulcer].

The response of serum gastrin, insulin and glucagon to administration of sodium bicarbonate (SB) followed by cimetidine was studied in 35 duodenal ulcer patients. Relevant measurements were made using radioimmunoassay kits "Diagnostic" (USA) and "Oris" (France). It was established that SB administration induced a significant rise in gastrin levels while those of insulin, glucagon and gastrin lowered significantly following cimetidine treatment (gastrin levels progressed to baselines).

[Pancreatic hormonal function and proteolytic activity in peptic ulcer].

Blood serum insulin, glucagon, pepsinogen, trypsin was studied by radioimmunological methods in 95 patients with ulcer disease. Fasting values and values 1 and 2 hours after a standard breakfast (1212 kcal) were evaluated. It was established that all patients showed a statistically valid increase of the basal level of glucagon while patients with gastric ulcer showed an increase of the basal insulin level.

[Effect of acute hypoxia on the renin and erythropoietin activities of the blood serum in rats].

A comparative study of renin and erythropoietin content in the blood serum of rats with "endocrine" kidneys and changes in their activity following the action of specific erythropoietic stimulus (4-hour hypoxia) has been conducted. The presence of "endocrine" kidneys increased renin and erythropoietin activity in such animals. Acute hypoxia produced further increase in erythropoietin titre in the blood serum, with renin remaining at the same level.

[Effect of immunostimulants of steroidogenesis on the activity of various oxidative enzymes in the adrenal glands and other organs].

Effect of IgG from rabbits, immunized with deoxyribonucleoprotein and with nuclear matrix of rat adrenal glands, on activities of cytochrome c oxidase, glucose-6-phosphate (G6PD) and lactate (LDH) dehydrogenases was studied in rat adrenal glands, liver and spleen tissues, myocardial and skeletal muscles. After administration of the antibodies and deoxynucleoprotein activation of the oxidative enzymes was tissue-dependent. Activities of cytochrome c oxidase and G6PD were distinctly increased in adrenal glands.

[Incretory changes in the pancreatic hormones in chronic pancreatitis].

Radioimmunoassay was employed to study blood content of insulin, C-peptide and glucagon in 78 patients with chronic pancreatitis. It was revealed that during exacerbation, there was an increase in the content of insulin and glucagon and, to a lesser degree, in that of C-peptide. During remissions, part of the patients showed insular deficiency which increased with disease standing.

[Physiological significance of specific immunoglobulins in regulating steroidogenesis in adrenal cortex cells].

The data obtained suggest the existence of physiological immunoglobulin mechanisms regulating the functions of the cells including hormone--producing ones. Serologically identical antigens were revealed both in the blood and the extracts from adrenocortical cell nuclei of intact rats. Apart from that, autoantibodies to deoxyribonucleoprotein (DNP) of adrenocortical cells were found in the blood sera of normal animals.