Distinct properties of functional KCC2 expression in immature mouse hippocampal neurons in culture and in acute slices

A hallmark in the development of GABAergic neurotransmission is the switch in GABA(A)-mediated responses from depolarizing to hyperpolarizing. This occurs due to a gradual decrease in the intracellular concentration of chloride caused by the functional expression of the neuron-specific K-Cl cotransporter KCC2. Whether a mere increase in the amount of KCC2 protein is the rate-limiting step in vivo, or a further activation of the otherwise nonfunctional cotransporter is required, is not clear. Imposing a fixed Cl(-) load via patch pipette we measured the resultant somato-dendritic gradients in reversal potential of GABAergic currents to determine the time course of functional maturation of KCC2-mediated Cl(-) extrusion in two preparations: cultured mouse hippocampal neurons plated at embryonic day 17 and CA1 pyramidal cells in acute slices. We found that in immature neurons in both preparations the gradient is initially small or not detectable. It undergoes an abrupt increase at around days 13-14 in culture, while a more gradual increase occurs between postnatal days 5-14 in slices. Consistent with the presence of a nonfunctional form of KCC2 in immature hippocampal neurons grown in culture, application of the broad-spectrum kinase inhibitor staurosporine produces a rapid and potent up-regulation of KCC2 function in these cultured neurons, but not in neonatal slices. Taken together with our previously published data, these results indicate that the functional activity of KCC2 in vivo parallels the developmental expression of the protein, whereas cultured neurons require an additional activation step (mimicked by staurosporine) for KCC2 to become functional.     

Changes in intracellular potassium concentration in a one-cell mouse embryo after enucleation

Comparative analysis of potassium concentrations in the cytoplasm of intact and enucleated one-cell mouse embryos of showed that microsurgical manipulations during collection of pronuclei disordered potassium homeostasis in the embryonic cell.Translated from Byulleten Eksperimentalnoi Biologii i Meditsiny, Vol. 138, No. 9, pp. 275–276, September, 2004     

Liver pathology in patients with primary hemochromatosis--homozygous carriers of C282Y mutation

Liver pathology was studied in 3 patients with primary chemochromatosis. In two cases so-called iron free foci with signs of hepatocytes with feature of dysplasia were found. Many siderosomes were found ultrastructurally in the cytoplasma of hepatocytes. Histological markers of virus infection were absent in a patient with positive serum HbsAg and HCV-Ab. Alcohol did not produce typical histological changes. In this case grave liver reticuloendothelial hemosiderosis typical for secondary hemochromatosis and overloading with iron of spleen pulp according to MR imaging were observed.     

Skin repair by transplantation of cultured keratinocytes

Improvement of methods for culturing skin cells stimulates their wide application in the treatment of a variety of skin injuries. A method for restoration of the skin with cultured epithelium and cultured epithelium in combination with a derma analog (collagen gel with fibroblasts) was developed. Possible mechanisms for skin repair after transplantation of cultured allogenic skin transplants were analyzed.     

Cell-binding properties of glycoprotein B of Aujeszky's disease virus

The glycoprotein B (gB) of Aujeszky's disease virus (ADV) has a role in virus entry and cell-to-cell spread. In this report we examined the cell-binding properties of native ADV gB purified from the virus envelope by affinity chromatography. The binding of gB to the surface of susceptible cells BHK-21 and MDBK was specific, dose-dependent, and nearly saturable, which is characteristic of conventional receptor-ligand interactions. The purified gB was shown to specifically bind to immobilised heparin. The addition of soluble exogenous heparin and heparinase treatment of cells inhibited the binding of gB to the cells. Cell-associated gB could also be dissociated from the cells by soluble heparin. The results indicated that ADV gB binds specifically to cellular heparan sulphate. The binding of gB to cells inhibited the attachment of virus to cells and thus the formation of viral plaques. The results suggest that ADV gB may have a function in the initial attachment of ADV to the surface of susceptible cells.     

Effects of preemptive analgesia on pain and cytokine production in the postoperative period

BACKGROUND: The postoperative period is associated with increased production of proinflammatory cytokines, which are known to augment pain sensitivity, among other effects. In a previous study, the authors found that patients treated with patient-controlled epidural analgesia (PCEA) exhibited attenuated proinflammatory cytokine response in the postoperative period. In the present study, the authors examined whether preemptive analgesia continued with PCEA may further attenuate the proinflammatory cytokine response and reduce pain sensitivity in the postoperative period. They compared cytokine production in two groups of patients, one receiving PCEA, the other receiving preemptive epidural analgesia continued by PCEA. METHODS: Female patients hospitalized for transabdominal hysterectomy were randomly assigned to one of two pain management techniques: PCEA or preemptive epidural analgesia followed by PCEA (PA + PCEA). Postoperative pain was assessed using the visual analog scale. Blood samples were collected before, 24, 48, and 72 h following surgery. Production of the following cytokines was assessed in stimulated peripheral blood mononuclear cells: interleukin (IL)-1beta, tumor necrosis factor alpha, IL-6, IL-1ra, IL-10, and IL-2. RESULTS: Patients of the PA + PCEA group exhibited lower pain scores throughout the 72 h postoperatively, compared with patients of the PCEA group. In patients of the PA + PCEA group in the postoperative period, production of IL-1beta, IL-6, IL-1ra, and IL-10 was significantly less elevated, while IL-2 production was significantly less suppressed. CONCLUSIONS: Proinflammatory cytokines are key mediators of illness symptoms, including hyperalgesia. The present results suggest that preemptive epidural analgesia is associated with reduced postoperative pain and attenuated production of proinflammatory cytokines.     

Role of phagocytosis activation in the mechanism of therapeutic effect of medical ozone in patients with sluggish purulent inflammations of maxillofacial soft tissues

Sixty-three patients with local sluggish suppurative inflammations of maxillofacial soft tissues were examined. Medical ozone was added to the treatment protocols of 30 of these patients. Before treatment peripheral blood leukocyte phagocytic activity was decreased in 54 patients, which corresponded to clinical form of a sluggish inflammation. Traditional therapy did not appreciably change the level of phagocytosis. Addition of medical ozone exposure to therapy promoted normalization of leukocyte phagocytic activity and accelerated liquidation of inflammation.