The object of this research is to study acoustic emissions (AE) in aqueous solutions of polyethylene glycols (PEGs) of molecular masses from 300 to 3000 during cooling at 100 degrees C/min and heating at 70 degrees C/min in the temperature range from 0 to -196 degrees C. The dependence of AE intensity on PEG concentration and molecular mass is analysed. The AE intensity correlated with the crystalline to amorphous phase ratio in the frozen system.
Activity of hexokinase, phosphorylase, glucoso-6-phosphate dehydrogenase lactate-dehydrogenase was studied in liver slices, homogenate and supernatant fraction after freezing at a rate of 1 degree/min down to -30 degrees C. The enzyme activity in homogenate and supernatant fraction does not change after freezing. A significant reduction in the activity of most enzymes that is followed by an increase in their activity in the freezing medium was observed in the experiments. Cryoprotectant polyethylene glycol, mol. wt. 300 and 1,000 (PEG-300 and PEG-1,000), partially prevents the observed changes in the enzyme activity; PEG-1,000 is more effective than PEG-300. Experimental results show that the main reason for the reduction of the enzyme activity observed after freezing the tissue slices is a decrease in the volume of intracellular enzyme proteins due to their leakage from the injured cellular elements into the exocellular medium.
Lysosomal enzyme activity in the bile and blood serum was compared in mice with experimental intrahepatic cholestasis induced by alpha-naphthyl isothiocyanate and Triton WR 1339. Triton WR 1339 increases the synthesis of cholesterol (fatty acid precursor) in liver cells. The development of intrahepatic cholestasis was confirmed by the increase in activities of alkaline phosphatase and gamma-glutamyltransferase in blood serum. Administration of Triton WR 1339 in a dose of 100 mg/100 g was followed by a 10-fold increase in beta-galactosidase activity (hepatocyte lysosomal enzyme) in the bile, but not in the serum of mice. beta-Galactosidase activity significantly increased in the bile, but decreased in the serum of mice after treatment with a-naphthyl isothiocyanate in a dose of 200 mg/kg. Our results indicate that intrahepatic cholestasis is manifested in increased secretion of lysosomal glycosidases into the bile. Bile components can aggravate damage to liver cells by affecting the processes of hepatocyte apoptosis and necrosis.
A method for the purification of mouse monoclonal antibodies from hybridoma culture supernatants is described. The protocol involves the use of a combination of three previously described methods for the concentration and purification of monoclonal antibodies. Firstly, hybridomas were grown in a Diacult dialysis system (Inter Med Laboratory, Denmark) to yield milligram quantities of monoclonal antibody in a culture supernatant. Monoclonal antibodies were then purified from the culture supernatant by precipitation with polyethylene glycol 6000 (PEG 6000) and finally reprecipitated using an ammonium sulphate procedure. The PEG 6000 treatment caused a density change in the ammonium sulphate immunoglobulin precipitate, and resulted in the formation of a pellicle which contained pure mouse monoclonal antibody. The protocol removed contaminating bovine serum immunoglobulin as well as other serum and cellular protein from the monoclonal antibody preparations.
OBJECTIVE: To compare healing of one-layer colonic anastomoses with or without a soluble intraluminal prosthesis (* SBS-tube). DESIGN: Randomised, partly blinded controlled study. SETTING: University hospital, Denmark. SUBJECTS: 16 female Danish country strain pigs, of which 8 had the SBS tube inserted and 8 acted as controls. INTERVENTIONS: One-layer colonic anastomoses either hand-sewn (n = 8, controls) or hand-sewn onto an SBS tube (n = 8). MAIN OUTCOME MEASURES: Macroscopic evaluation, leakage test, breaking strength, histology, oxygen tension in and near the anastomosis peroperatively and 4 days postoperatively. RESULTS: Three quarters of the tubes (n = 8) dissolved in less than 2 hours. Histological examination showed significantly better structured layers and more mucosal epithelial covering in the SBS group. The other histological variables examined were: tissue gap (p
Exactly 30 years ago, hepatitis C virus was identified. Over the years, tremendous success has been achieved in the treatment of hepatitis C, which is currently considered to be an almost completely curable disease. The review presents the main stages in the development of hepatitis C antiviral therapy, the efficacy of various treatment regimens. The greatest progress in treatment was noted over the past 5 years when drugs with direct antiviral action appeared and began to be widely used, including in Russia, which ensure the elimination of the virus in 90-95% of cases.
OBJECTIVES: Cytotoxic methacrylate monomers have been identified in aqueous extracts of freshly cured compomers. Some of these compounds, including HEMA and TEGDMA, induce apoptosis and necrosis in vitro. The aim of the present study was to elucidate possible signaling pathways involved in apoptosis following exposure to HEMA or TEGDMA in a salivary gland cell line. METHODS: The cells were exposed to various concentrations of HEMA or TEGDMA. ROS formation was determined by dichlorofluorescein assay. Phosphorylated MAP-kinases ERK1/2, p38 and JNK, as well as specific caspases were identified by Western blotting. Apoptosis was assayed by fluorescence microscopy. RESULTS: HEMA or TEGDMA exposure resulted in ROS formation and concentration-dependent apoptosis as well as phosphorylation of ERK. Phosphorylation of JNK and p38 was induced by HEMA. Selective inhibitors of ERK and JNK modified the apoptotic response after HEMA and TEGDMA exposure, whereas p38 inhibition modified the apoptotic response only after HEMA exposure. Vitamin C reduced HEMA-induced apoptosis. SIGNIFICANCE: ROS formation and differential MAP kinase activation appear to be involved in the apoptotic response following exposure to HEMA and TEGDMA.
The adhesive strength of autologous fibrinogen sealants prepared from the individual patient's blood with the help of ammonium sulphate or polyethylene glycol was compared to that of a homologous commercial fibrinogen sealant. The concentration of the fibrinogen harvested by each method was measured. The bonding power measurements were carried out by gluing pieces of human dura, rat skin, or cotton cloth together. The commercial fibrinogen sealant yielded the highest concentration of fibrinogen and also proved to be the strongest of the glues tested. The PEG glue was better than the AS glue. Humidity did not have a significant influence on adhesive strength, nor did deep-freezing worsen the properties of the fibrinogen sealants. In addition to the commercial products, the self-made fibrinogen glues, especially the PEG glue, were also strong enough for otolaryngological use.
Currently available preparations for colonoscopy have low tolerability and may cause fluid and electrolyte shifts. An alternative method of bowel cleansing is required.
Preparation of the gut using oral nutritional supplements (ONS) and rectal enema was tested as an alternative method of bowel cleansing. During 2008-2012, patients were randomized to oral nutritional supplements (n = 27) for 5 days and rectal enema or polyethylene glycol (PEG) (n = 23) prior to colonoscopy. Blinded endoscopists rated the degree of bowel cleansing according to the Ottawa bowel preparation scale (OBS) (primary outcome). Tolerability of either preparation was also assessed (ClinicalTrials.gov. Identifier no: NCT00123456).
Due to a high rate of bowel cleansing failure among patients receiving ONS, the study was interrupted prematurely. Colonoscopies were incomplete due to stools in 6 of 27 patients in the ONS group compared to 1 of 23 in the PEG group (ns). The mean total OBS were 8.3 ± 3.3 and 5.3 ± 2.8, respectively (p = 0.002). Four patients (15%) in the ONS group and eight patients (35%) receiving PEG had an OBS score =4 (good preparation) (ns). ONS was better tolerated than PEG with more patients reporting acceptable taste (27 of 27 [100%] vs. 15 of 23 [65%], p = 0.001), and fewer reporting difficulties with the intake (0 of 27 [0%] vs. 10 of 23 [43%], p
Cell surface proteins of two slime-forming, encapsulated Streptococcus cremoris strains, MLS96 and T5 from the fermented milk product viili, were extracted with the non-ionic detergent Triton X-100. The isolated protein antigens were characterized by sodium dodecyl sulphate polyacrylamide gel electrophoresis and immunoblotting with antisera produced against whole Strep. cremoris cells. When protein profiles of these strains were compared, seven prominent polypeptides were found common to both and were recognized by both antisera. Five of these polypeptides with molecular weights of 70,000, 54,000, 50,000, 47,000 and 40,000 were identified as cell wall components. The remaining two polypeptides with molecular weights of 42,000 and 26,000 are being studied further in connection with slime formation for which modified Triton X-100 extraction provides a suitable method for isolation of the surface-associated antigens of lactic streptococci.