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121.
Sacid Coban Fahrettin Yildiz Alpaslan Terzi Behcet Al Nurten Aksoy Muharrem Bitiren Hakim Celik 《Cell biochemistry and function》2010,28(1):83-88
Nigella sativa (NS) has been shown to have antioxidant and antiinflammatory activities in different conditions. The goal of this study was to evaluate the effects of NS on cholestatic liver injury in rats. Thirty rats were recruited in the study as follows: Group 1, Bile duct ligation (BDL) (n = 10); Group 2, BDL plus NS (n = 10); and Group 3, Sham (n = 10). Bile duct ligated group received 0.2 mL kg?1 dose of NS intraperitoneally daily throughout 14 days. Liver damage and cholestasis were determined by the biochemical and the pathologic examination. Data showed a decrease in gamma glutamyl transferase (GGT), alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) activities of the NS treated rats when compared with BDL group (p < 0.001 for GGT and p < 0.05 for others). The NS treated rats' tissue levels of total oxidant status (TOS), oxidative stress index (OSI), and myeloperoxidase (MPO) were significantly lower than that of the BDL group (p < 0.01 for all). Increases in total antioxidant capacity (TAC) and catalase (CAT) levels were statistically significant in the NS treated rats compared to BDL group (p < 0.01 for both). On the other hand, administration of NS in the rats with biliary obstruction resulted in inhibition of necro‐inflammation. These results indicate that NS exerts a therapeutic effect on cholestatic liver injury in bile duct ligated rats possibly through attenuation of enhanced neutrophil infiltration and oxidative stress in the liver tissue. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
122.
Characterization of Streptococcus bovis from the rumen of the dromedary camel and Rusa deer 总被引:1,自引:0,他引:1
AIMS: Isolation and characterization of Streptococcus bovis from the dromedary camel and Rusa deer. METHODS AND RESULTS: Bacteria were isolated from the rumen contents of four camels and two deer fed lucerne hay by culturing on the semi-selective medium MRS agar. Based on Gram morphology and RFLP analysis seven isolates, MPR1, MPR2, MPR3, MPR4, MPR5, RD09 and RD11 were selected and putatively identified as Streptococcus. The identity of these isolates was later confirmed by comparative DNA sequence analysis of the 16S rRNA gene with the homologous sequence from S. bovis strains, JB1, C14b1, NCFB2476, SbR1, SbR7 and Sb5, from cattle and sheep, and the Streptococcus equinus strain NCD01037T. The percentage similarity amongst all strains was >99%, confirming the identification of the camel isolates as S. bovis. The strains were further characterized by their ability to utilize a range of carbohydrates, the production of volatile fatty acids (VFA) and lactate and the determination of the doubling time in basal medium 10 supplemented with glucose. All the isolates produced l-lactate as a major fermentation end product, while four of five camel isolates produced VFA. The range of carbohydrates utilized by all the strains tested, including those from cattle and sheep were identical, except that all camel isolates and the deer isolate RD11 were additionally able to utilize arabinose. CONCLUSIONS: Streptococcus bovis was successfully isolated from the rumen of camels and deer, and shown by molecular and biochemical characterization to be almost identical to S. bovis isolates from cattle and sheep. SIGNIFICANCE AND IMPACT OF THE STUDY: Streptococcus bovis is considered a key lactic acid producing bacterium from the gastrointestinal tract of ruminants, and has been implicated as a causative agent of lactic acidosis. This study is the first report of the isolation and characterization of S. bovis from the dromedary camel and Rusa deer, and suggests a major contributive role of this bacterium to fermentative acidosis. 相似文献
123.
Song YC Jin S Louie H Ng D Lau R Zhang Y Weerasekera R Al Rashid S Ward LA Der SD Chan VL 《Molecular microbiology》2004,53(2):541-553
Type III secretion systems identified in bacterial pathogens of animals and plants transpose effectors and toxins directly into the cytosol of host cells or into the extracellular milieu. Proteins of the type III secretion apparatus are conserved among diverse and distantly related bacteria. Many type III apparatus proteins have homologues in the flagellar export apparatus, supporting the notion that type III secretion systems evolved from the flagellar export apparatus. No type III secretion apparatus genes have been found in the complete genomic sequence of Campylobacter jejuni NCTC11168. In this study, we report the characterization of a protein designated FlaC of C. jejuni TGH9011. FlaC is homologous to the N- and C-terminus of the C. jejuni flagellin proteins, FlaA and FlaB, but lacks the central portion of these proteins. flaC null mutants form a morphologically normal flagellum and are highly motile. In wild-type C. jejuni cultures, FlaC is found predominantly in the extracellular milieu as a secreted protein. Null mutants of the flagellar basal rod gene (flgF) and hook gene (flgE) do not secrete FlaC, suggesting that a functional flagellar export apparatus is required for FlaC secretion. During C. jejuni infection in vitro, secreted FlaC and purified recombinant FlaC bind to HEp-2 cells. Invasion of HEp-2 cells by flaC null mutants was reduced to a level of 14% compared with wild type, suggesting that FlaC plays an important role in cell invasion. 相似文献
124.
125.
Al Zaid Siddiquee K Arauzo-Bravo MJ Shimizu K 《Applied microbiology and biotechnology》2004,63(4):407-417
Metabolic flux analysis based on 13C-labeling experiments followed by the measurement of intracellular isotope distribution using both 2D NMR and GC-MS was carried out to investigate the effect of pyruvate kinase (pyk) gene knockout on the metabolism of Escherichia coli in continuous culture. In addition, the activities of 16 enzymes, and the concentrations of 5 intracellular metabolites, were measured as a function of time in batch culture as well as continuous culture. It was found that flux through phosphoenol pyruvate carboxylase and malic enzyme were up-regulated in the pykF– mutant as compared with the wild type, and acetate formation was significantly reduced in the mutant. In addition, flux through the phosphofructose kinase pathway was reduced and that through the oxidative pentose phosphate (PP) pathway increased in the mutant. This was evidenced by the corresponding enzyme activities, and the increase in the concentrations of phosphoenol pyruvate, glucose-6-phosphate and 6-phosphogluconate, etc. It was also found for continuous cultivation that the enzyme activities of the oxidative PP and Entner-Doudoroff pathways increased as the dilution rate increased for the pykF– mutant. To clarify the metabolism quantitatively, it was found to be quite important to integrate the information on intracellular metabolic flux distribution, enzyme activities and intracellular metabolite concentrations. 相似文献
126.
Infections caused by Flavobacterium psychrophilum include 'bacterial coldwater disease' (BCWD) and 'rainbow trout fry syndrome' (RTFS), which are severe diseases that can cause high mortality and significant losses in hatchery-reared salmonids worldwide. Usually, these conditions start with necrosis along the edge of the fins. As the infection progresses, both the fish surface and the internal organs can be involved. The aetiological agent produces a Ca-dependent protease that can be responsible for some of the pathogenic responses, although the precise nature of the response remains to be elucidated. Atlantic salmon Salmo salar were experimentally infected by F. psychrophilum in order to investigate the bacterial invasion in the fin tissues by scanning electron microscopy. The images showed numerous bacteria embedded in the mucous layer when this remained on the tegument. In other zones without mucus, it was observed that bacteria were present on the axis of fin rays, but not on the epidermal surface. The material on these axes was largely eroded by tubular boreholes, and bacterial rods could be seen in these perforations. EDX (Energy Dispersive X-ray) microanalysis of the axis of the fin rays showed significant amounts of P and Ca, revealing the ossification of the ray axis. The protease activity could explain the formation of the tubular boreholes, allowing the bacteria the necessary Ca for the activation of the enzyme. The erosion pattern suggests that the gliding motility of F. psychrophilum could be involved in this burrowing ability. 相似文献
127.
Zadrazil J Jabry SA Bachleda P Gibejová A 《Biomedical papers of the Medical Faculty of the University Palacky, Olomouc, Czechoslovakia》2004,148(2):171-173
This paper presents our experience to date with using a cyclosporine formulation Equoral (IVAX Pharmaceuticals) together with mycophenolate mofetil plus a steroid immunosuppressive regimen in the treatment of de novo renal transplant recipients. Ten cadaveric donor renal transplant recipients of mean age 51.6 years (range 37-66) were followed up over 6 months for the development of rejection attacks and side effects. All patients received prednisolone, mycophenolate mofetil (1 g/day during the first 5 days posttransplant and then 20 mg/kg/day) plus cyclosporine (3 mg/kg/day). Biopsy proven acute rejection episodes were observed in 2 out of 10 patients (20%). Six months patient as well as renal graft survival rate was 100%. The development of graft function was immediate after transplantation. The mean serum creatinine levels were gradually decreased. Over the 6-month posttransplant period, the function of the graft was satisfactory and stable. The majority of observed adverse events were those commonly reported with the use of cyclosporine and they resolved with a reduction in cyclosporine dose. Equoral treatment demonstrated an acceptable safety profile with maintenance of adequate renal function without incidence of malignancy/lymphoproliferative disease or serious infections. In conclusion, Equoral plus mycophenolate mofetil immunosuppression seems effective and safe on terms acute rejection rates, patient and renal graft survival rates and side profiles. 相似文献
128.
The Eimeria genome projects: a sequence of events 总被引:8,自引:0,他引:8
Shirley MW Ivens A Gruber A Madeira AM Wan KL Dear PH Tomley FM 《Trends in parasitology》2004,20(5):199-201
129.
Polyprotein processing protease of African swine fever virus: purification and biochemical characterization
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The purified recombinant African swine fever virus polyprotein processing protease cleaves the two GG-X sites in polyprotein pp62 with the same efficiency. Cleavage at the site that is first recognized in vivo is not a requisite for cleavage at the second site, suggesting the existence of mechanisms that control the ordered processing of the polyprotein during infection. 相似文献
130.
Siegel DH Ashton GH Penagos HG Lee JV Feiler HS Wilhelmsen KC South AP Smith FJ Prescott AR Wessagowit V Oyama N Akiyama M Al Aboud D Al Aboud K Al Githami A Al Hawsawi K Al Ismaily A Al-Suwaid R Atherton DJ Caputo R Fine JD Frieden IJ Fuchs E Haber RM Harada T Kitajima Y Mallory SB Ogawa H Sahin S Shimizu H Suga Y Tadini G Tsuchiya K Wiebe CB Wojnarowska F Zaghloul AB Hamada T Mallipeddi R Eady RA McLean WH McGrath JA Epstein EH 《American journal of human genetics》2003,73(1):174-187
Kindler syndrome is an autosomal recessive disorder characterized by neonatal blistering, sun sensitivity, atrophy, abnormal pigmentation, and fragility of the skin. Linkage and homozygosity analysis in an isolated Panamanian cohort and in additional inbred families mapped the gene to 20p12.3. Loss-of-function mutations were identified in the FLJ20116 gene (renamed “KIND1” [encoding kindlin-1]). Kindlin-1 is a human homolog of the Caenorhabditis elegans protein UNC-112, a membrane-associated structural/signaling protein that has been implicated in linking the actin cytoskeleton to the extracellular matrix (ECM). Thus, Kindler syndrome is, to our knowledge, the first skin fragility disorder caused by a defect in actin-ECM linkage, rather than keratin-ECM linkage. 相似文献