排序方式: 共有247条查询结果,搜索用时 15 毫秒
61.
62.
63.
Celik S Gorur S Aslantas O Erdogan S Ocak S Hakverdi S 《Molecular and cellular biochemistry》2007,297(1-2):131-138
Although oxidative damage is known to be involved in inflammatory-mediated tissue destruction, modulation of oxygen free radical
production represents a new approach to the treatment of inflammatory diseases. Caffeic acid phenethyl ester (CAPE), an active
component of propolis from honeybee hives, has antioxidant, anti-inflammatory and antibacterial properties. For that reason,
we aimed to investigate the efficiency of CAPE administration in preventing oxidative damage in pyelonephritis (PYN) caused
by Escherichia coli. In this study, 35 Wistar rats were grouped as follows: control, PYN 24 h, PYN 48 h, PYN 72 h, CAPE 24 h, CAPE 48 h and CAPE
72 h. E. coli (1 × 109 c.f.u.) were inoculated into the rats in both PYN and CAPE groups via urethral catheterization. Ten μM/kg-body weight CAPE
was injected to the rats in all CAPE groups 24 h before E. coli infection, and injections were repeated at 24-h intervals. Rats were sacrificed 24 h, 48 h and 72 h after infection in both
PYN and CAPE groups. Malondialdehyde (MDA) and nitric oxide (NO) levels were significantly increased in kidneys of PYN groups.
The activities of the antioxidant enzymes, catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and
xanthine oxidase (XO) were also elevated by E. coli. However, CAPE administration reduced MDA and NO levels, as well as XO activity, although it increased SOD and GSH-Px activities.
Histopathological examination showed that CAPE reduced the inflammation grade induced by E. coli. In conclusion, CAPE administrations decrease the oxidative damage occurring in PYN and therefore could be used for medical
management of bacterial nephropathy. 相似文献
64.
Ertan T Yildiz I Ozkan S Temiz-Arpaci O Kaynak F Yalcin I Aki-Sener E Abbasoglu U 《Bioorganic & medicinal chemistry》2007,15(5):2032-2044
A new series of N-(2-hydroxy-4(or 5)-nitro/aminophenyl)benzamide and phenylacetamide derivatives (1a-1n, 2a-2n) were synthesized and evaluated for antibacterial and antifungal activities against Staphylococcus aureus, Bacillus subtilis, Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coli, Candida albicans, and their drug-resistant isolate. Microbiological results indicated that the compounds possessed a broad spectrum of activity against the tested microorganisms at MIC values between 500 and 1.95 microg/ml. Benzamide derivative 1d exhibited the greatest activity with MIC values of 1.95, 3.9, and 7.8 microg/ml against drug-resistant B. subtilis, B. subtilis, and S. aureus, respectively. 相似文献
65.
Ozkan A Kin-Isler A 《Journal of strength and conditioning research / National Strength & Conditioning Association》2007,21(1):296-300
The purpose of this study was to determine the reliability and validity of regulating exercise intensity by ratings of perceived exertion in step dance sessions. Ten male college-aged students voluntarily participated in 2 step dance sessions for 45 minutes at 70-80% of their heart rate (HR) reserves with a 1-week interval between sessions. The step dance sessions included the same choreography with 10 minutes of warm-up, 25 minutes of the main part, 5 minutes of calisthenics for legs and abdomen, and 5 minutes of cool-down. In each session, subjects' ratings of perceived exertion (RPEs) were determined by Borg's 6-20 scale together with HR and lactic acid (LA) levels with 10-minute intervals. Values for RPE, HR, and LA increased nonlinearly in both sessions, and their trends were explained by polynomial equations to the second degree. The RPE values increased throughout each session, whereas HR and LA showed a decrease in the last time interval, which indicated that RPE did not maintain exercise intensity at proper range. Reliability coefficients for RPE scores in the first and last session ranged from 0.602 to 0.684. These findings suggest that RPE was a reliable but not a valid method for regulating exercise intensity in step dance sessions. 相似文献
66.
Ebru Cayir Aysegul Erdemir Ebru Ozkan Murat Topuzogullari Zeynep Busra Bolat Ayberk Akat Dilek Turgut-Balik 《Molecular biotechnology》2014,56(8):689-696
Tropical theileriosis is a disease caused by infection with an apicomplexan parasite, Theileria annulata, and giving rise to huge economic losses. In recent years, parasite resistance has been reported against the most effective antitheilerial drug used for the treatment of this disease. This emphasizes the need for alternative methods of treatment. Enolase is a key glycolytic enzyme and can be selected as a macromolecular target of therapy of tropical theileriosis. In this study, an intron sequence present in T. annulata enolase gene was removed by PCR-directed mutagenesis, and the gene was first cloned into pGEM-T Easy vector and then subcloned into pLATE31 vector, and expressed in Escherichia coli cells. The enzyme was purified by affinity chromatography using Ni–NTA agarose column. Steady-state kinetic parameters of the enzyme were determined using GraFit 3.0. High quantities (~65 mg/l of culture) of pure recombinant T. annulata enolase have been obtained in a higly purified form (>95 %). Homodimer form of purified protein was determined from the molecular weights obtained from a single band on SDS-PAGE (48 kDa) and from size exclusion chromatography (93 kDa). Enzyme kinetic measurements using 2-PGA as substrate gave a specific activity of ~40 U/mg, K m: 106 μM, kcat: 37 s?1, and k cat/K m: 3.5 × 105 M?1 s?1. These values have been determined for the first time from this parasite enzyme, and availability of large quantities of enolase enzyme will facilitate further kinetic and structural characterization toward design of new antitheilerial drugs. 相似文献
67.
We have investigated the temperature-dependent interaction of the porins OmpF from Paracoccus denitrificans and OmpG from Escherichia coli with lipid molecules after reconstitution in lecithin. Effects of incubation at increased temperatures on activity were tested by functional experiments for OmpG and compared with previously published results of OmpF in order to understand the activity loss of OmpF with monomerization. Protein-lipid interaction was monitored by different reporter groups both from lipid molecules and from protein. OmpF loses its activity by approximately 90% at 50 degrees C while OmpG does not show a temperature-dependent change in activity between room temperature and 50 degrees C. The interaction between OmpF and lipid molecules is severely altered in a two-step mechanism at 55 and approximately 75 degrees C for OmpF. The first step is attributed to changes in the degree of interaction between the aromatic girdle of OmpF and the interfacial region of the lipid bilayer, leading to monomerization of this trimeric porin. The second step at 75 degrees C is attributed to the changes in lipid-porin monomer interaction. Around 90 degrees C, reconstituted porin aggregates. For OmpG, changes in lipid-protein interaction were observed starting from approximately 80 degrees C because of temperature-induced breakdown of its folding. This study provides deeper understanding of porin-lipid bilayer interaction as a function of temperature and can explain the functional breakdown by monomerization while porin secondary structure is still preserved. 相似文献
68.
Ozkan AT Celebi B Babür C Lucio-Forster A Bowman DD Lindsay DS 《The Journal of parasitology》2008,94(4):817-820
Blood samples from 99 cats from the Ankara province of Turkey were examined for the presence of anti-Toxoplasma gondii antibody with the use of both the Sabin-Feldman dye test (DT) and an indirect fluorescent antibody test (IFAT). Forty of the 99 sera (40.3%) were positive for antibodies against T. gondii with the DT, whereas the IFAT assay detected antibodies in 34 (34.3%). The study also evaluated 3 factors for their potential association with the presence of T. gondii antibody: age (<1 yr, 1-2 yr, and >2 yr), gender (female vs. male), and outdoor access (stray, owned with outdoor access, or indoor only). The DT detected antibodies in 3 cats under 1 yr of age, 22 cats between 1 and 2 yr, and 15 cats older than 2 yr, whereas the IFAT found 1, 18, and 15 cats positive for antibodies, respectively, in each of these categories. Of 61 female cats, 27 (44.2%) were positive by the DT; and of 38 male cats, 13 (34%) were positive by the DT. For the IFAT, 24 female cats (39.3%) and 10 male cats (26.3%) were positive. The percent seropositivity in indoor cats was 30.8% by the DT and 23.1% by the IFAT. In stray cats, the percent seropositivity was 52.8% by the DT and 41.7% by the IFAT. Antibody presence was significantly associated with age, but not with outdoor access. 相似文献
69.
70.