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Quantitative analysis of blood vessels in the distal segment of rat sciatic nerve after its ligation for 40 sec and subperineurial administration of mesenchymal stem cells or dissociated cells of rat embryonic spinal cord was carried our by immunohistochemical tracing of von Willebrand factor, a marker of endothelial cells of blood vessels. It was found that the number of blood vessels per unit area of the nerve trunk in 21 days after injury and administration of mesenchymal stem cells increased by more than 1.5 times in comparison with the control (damaged nerve). After administration of dissociated cells of the embryonic spinal cord, this effect was not observed. It is assumed that mesenchymal stem cells stimulate the growth of vessels of the damaged nerve via production of angiogenic factors.

Experiments were performed on six female and 36 male adult Wistar rats to compare the influences of dissociated cells obtained from different embryonic CNS rudiments on the growth of regenerating nerve fibers in damaged recipient nerves. Sciatic nerves were damaged by application of a ligature, after which some animals received injections of suspensions of cells into the proximal nerve segment, using cells obtained by dissociation of spinal cord or anterior cerebral vesicle fragments from rats at 15 days of development. These experiments showed that injection of dissociated cells from embryonic spinal cord rudiments but not neocortex rudiments into the damaged nerve led to increases in number of myelinated nerve cells in recipients at 60 days.

A comparative study of the effect of tissue and suspension allografts of an embryonic spinal cord on regeneration of nerve fibers of impaired (by application of a ligature) sciatic nerve in rats was conducted. It was demonstrated that unlike tissue grafts that reach a large volume 21 and 60 days after transplantation, suspension grafts do not inhibit the growth of axons of the recipient to the periphery. It was established that introduction of a suspension of dissociated cells of the spinal cord embryonic anlages (but not fragments of these anlages) into the impaired sciatic nerve in rats results in an increase in the amount of myelinated regenerating nerve fibers of the recipient 60 days after the operation.

The aim of the present work was to identify the potential for implantation of dissociated embryonic spinal cord and neocortex rudiment cells into the sciatic nerve of Wistar rats and to study their differentiation. Cell suspensions prepared by dissociation of fragments of the cervical segment of the spinal cord and anterior cerebral vesicle of rat fetuses at 15 days of development were injected into the proximal segment of previously injured sciatic nerve. Studies using the immunohistochemical marker for stem/progenitor cells (Msi-1) showed that implanted cells could be identified in nerve trunks one day after surgery. At 21 days, some were fully differentiated into NeuN-immunopositive neurons, though the numbers of these cells were small. Most cells in neocortical transplants, in contrast to those of spinal cord transplants, were ependymocytes at 21 days after surgery.

The gene and cell therapy, stimulating the regeneration of damaged nerves is currently under development. In these experiments mesenchymal stem cells (MSCs) are often used. The purpose of this study is to describe the localization and morphological features of mesenchymal stem cells derived from bone marrow after their allografting into the damaged rat nerve. MSCs of the bone marrow of Wistar-Kyoto rats were obtained from Transtechnology LLC (Head G.Polyntsev, Ph.D.). MSCs were cultured, identified and labeled by 5-bromo-2’-deoxyuridine (BrdU) in vitro. The sciatic nerve of adult Wistar-Kyoto rats (n = 12) was damaged (ligature, 40 sec), and the suspension of BrdU+ MSCs (5 · 104 cells in 5 μl per animal) was immediately transplanted into the damaged sciatic nerve. In a previous study, we have showed that some transplanted cells are located in the epineurium of the recipient’s nerve. The perineurium of the recipient rats was studied in the present work. Perineurial cells have polygonal form, thin and flat cell nucleus and form several layers, the basement membranes being placed between them. Perineurium is characterized by the presence of occluding junctions that can be identified using anti-claudine antibodies. The use of antibodies to claudine allowed us to identify perineurium. Some BrdU+ MSCs were found to survive 5-7 d following surgery and according to their localization and morphology became perineurium cells. Such extracellular matrix proteins as laminin, fibronectin, collagen are present in the perineurium. Apparently, the presence of these proteins creates a favorable biological environment for MSCs survival and for their differentiation towards perineurium cells. The results of the study confirm the mesenchymal origin of perineurium cells.

A comparative study of the effect of tissue and suspension allografts of an embryonic spinal cord on regeneration of nerve fibers of impaired (by application of a ligature) sciatic nerve in rats was conducted. It was demonstrated that unlike tissue grafts that reach a large volume 21 and 60 days after transplantation, suspension grafts do not inhibit the growth of axons of the recipient to the periphery. It was established that introduction of a suspension of dissociated cells of the spinal cord embryonic anlages (but not fragments of these anlages) into the impaired sciatic nerve in rats results in an increase in the amount of myelinated regenerating nerve fibers of the recipient 60 days after the operation.

Fragments of the dorsolateral wall of the anterior brain vesicle from rat embryos on embryonic day 15 were dissociated and the resultant suspension containing single cells and cell aggregates was injected into the proximal segment of crushed sciatic nerve of adult animals for evaluation of their engrafting and differentiation under conditions of changed microenvironment. On days 1 and 21 postoperation, Msi-1, GFAP, NeuN, vimentin, and PCNA were detected by immunohistochemical methods. Small clusters of Msi-1-immunopositive cells were detected in the nerve trunks on the next day after transplantation. On day 21 after surgery, these precursors differentiate into nerve cells, astrocytes, and primarily ependymocytes.

Aim. To study the prevalence of metabolic syndrome in an unorganized population of Orenburg city. Methods. The sample was formed by the method of random numbers. Examined were 301 people aged 25 to 75 years, of which 148 were males and 153 females. Studied were the socio-demographic characteristics and medical history (including filling out of a questionnaire), the clinical status of study participants (with the measurement of blood pressure, height, weight, waist and hip circumference, biochemical blood analysis to determine the concentration of glucose and lipid profile). In order to identify the metabolic syndrome the following diagnostic criteria were used: of the Work Group on the treatment of adults of the National Cholesterol Education Program of the U.S. (2001-2005), of the International Diabetes Federation (2005) and of the All-Russian Scientific Society of Cardiology (2009). Results. The prevalence of abdominal obesity was reduced by using less stringent thresholds for waist circumference. The most common variant of the metabolic syndrome was the combination of the following components: abdominal obesity, arterial hypertension and a low content of high-density lipoproteins. According to the criteria of the International Diabetes Federation such a combination occurred in 7.6%, while in accordance with the Criteria of the Work Group on for the treatment of adults of the National Cholesterol Education Program of the U.S. - it occurred in 4.3%. Conclusion. The frequency of registration of the metabolic syndrome depends on the criteria for its diagnosis.

Regeneration of nerve fibers in rat sciatic nerve was quantitatively assessed after injury (ligation) and injection of dissociated cells derived from embryonic spinal cord. A suspension of dissociated spinal cord cells from rat embryos was transplanted under the perineurium of a nerve trunk. After transplantation, bromodeoxyuridine-labeled precursor cells survived and retained the label for more than 2 months; some of these cells differentiated into NeuNpositive neurons. Analysis of semithin sections of the distal nerve segment from the recipient taken at a distance of 0.5 cm from the site of injury showed that transplantation of dissociated cells of embryonic spinal cord led to an increase in the number of myelinated nerve fibers in the recipient nerve.

The purpose of this paper was to examine the possibilities of engraftment, and to study the differentiation of the dissociated cells from the embryonic primordia of the spinal cord and the neocortex of Wistar rats, after their transplantation into the sciatic nerve of adult animals. The cell suspension obtained as a result of a dissociation of fragments of the cervical spinal cord and the anterior cerebral vesicle from rat fetuses at day 15 of development, was injected into the proximal segment of a previously damaged sciatic nerve. Using the immunocytochemichal marker of neural stem/progenitor cells (Msi-1) the transplanted cells were identified in the nerve trunks after 1 day after the operation. After 21 day some of these cells underwent differentiation into NeuN-immunopositive neurons, however their number was small. Thus, dissociated precursor cells from embryonic rat spinal cord and neocortex survive for three weeks under conditions of transplantation into the damaged nerve and retain the ability to differentiate into neurons, but the number is small. Most of the cells in the neocortex transplants, unlike those from spinal cord transplants, within 21 days after the operation were represented by the ependymocytes.

Experiments on mice (CBA X C57 Bl6)F1 using endo- and exogenous cloning have shown that ultraviolet irradiation of blood enhances colony stimulating properties of plasma. Stimulation of colony formation occurs both in vitro, on direct contact of UV-irradiated blood plasma with bone marrow cells, and in vivo, upon this injection to the whole organism. In the latter case, increased migration of colony forming hematopoietic cells from the bone marrow can be noted. Single intravenous injection of syngenic UV-irradiated blood prevents inhibition of hematopoietic function of the bone marrow induced by closed brain injury.

The rabbit anti-mouse brain serum (RAMBS) that interacts with SC-1 marked cells, rather than with thymocytes and bone marrow cells, inhibits most of the blood and bone marrow colony-forming unit (CFU) population. A commercial thymus preparation thymalin increases the granulocytopoietic activity of the circulating CFU and decreases their sensitivity to RAMBS in thymectomized and normal animals. Differentiation of circulating CFU remains unchanged in thymalin-treated mice after RAMBS administration, while CFU erythroid activity of nontreated animals is lowered. The revealed changes in the CFU differentiation and sensitivity to RAMBS confirm the assumption that SC-1 antigen may mark Thy-1 lymphocytes of their microenvironment, rather than CFU.