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141.
Imamoğlu N Uyanik F Kocaoğlu Güçlü B Erdem O Cem Liman B Dönmez Altuntaş H 《Biological trace element research》2008,125(2):133-140
We report the effects of chromium picolinate (CrPic) on micronucleus frequency, morphology of lymphocytes, and lipid peroxidation
in calves. Twenty-four Holstein calves were selected for the study. They were kept in a farm and were fed a commercially available
calf diet and alfalfa, ad libitum. The animals were divided into three groups of eight subjects each and were treated as follows:
The first group was supplemented with a daily dose of 200 μg Cr as chromium picolinate; a second group received 400 μg Cr
per day and a third group that served as control received no supplemental chromium. After 12-week supplementation, blood samples
were collected to determine the micronucleus frequency, the apoptotic cell percentage, and the malondialdehyde (MDA) and blood
chromium levels. In both supplemented groups, the cells had irregularly shaped and segmented nuclei. Supplementation also
increased the percentage of apoptotic cells (p < 0.001) and serum MDA (p < 0.01) and slightly increased the chromium levels. The animals supplemented with 400 μg showed a significant increase of
micronucleus frequency (p < 0.01). The results of this study suggest that supplementation with 200 and 400 μg chromium as chromium picolinate may lead
to cytotoxicity. The higher level of supplementation may also have genotoxic effects. However, further studies investigating
the mechanism of the action of CrPic are required. 相似文献
142.
Effect of Strontium Ranelate on Hydrogen Peroxide-Induced Apoptosis of CRL-11372 Cells 总被引:2,自引:0,他引:2
Senkoylu A Yilmaz A Ergun MA Ilhan MN Simsek A Altun N Bolukbasi S Menevse S 《Biochemical genetics》2008,46(3-4):197-205
In vitro and in vivo studies have proven strontium to be an osteoinductive trace element. The effect of strontium ranelate
(SR) on H2O2-induced apoptosis of CRL-11372 cells and optimization of its anti-apoptotic dose were the aims of this study. After 1 h of
pretreatment with SR 1 μM, 50 μM, 100 μM, 500 μM, and 1,000 μM concentrations, CRL-11372 osteoblasts were exposed to 100 μM H2O2 for periods of 6–12 h. The same experiments were repeated without H2O2. The apoptotic index and viability of cells were assessed quantitatively with a fluorescent dye and qualitatively with agarose
gel electrophoresis. Concentrations of 1–100 μM of SR with a 6-h treatment and only 1 μM concentration with a 12-h treatment
inhibited the apoptotic effect of H2O2 on cultured osteoblasts significantly (P < 0.05). SR was shown to inhibit H2O2-induced apoptosis of CRL-11372 cells in a dose-dependent manner. 相似文献
143.
Pelin Aribal Kocatürk M. Cenk Akbostanci Canan Işikay Aylin Öcal Deniz Tuncel Güzin Özelçi Kavas Nermin Mutluer 《Biological trace element research》2001,80(2):115-124
Ischemia is associated with the pathological changes caused by the accumulation of reactive oxygen metabolites (ROM) in cerebrovascular
accident (CVA). The aim of this study was to determine red cell copper/zinc-superoxide dismutase (Cu/Zn-SOD) and catalase
activities and copper and zinc concentrations both in plasma and in red cells in CVA. Cu/Zn-SOD and catalase activities of
16 patients, with an average age of 64 yr, were measured spectrophotometrically; copper and zinc concentrations were determined
by atomic absorption spectrophotometer. The results showed that Cu/Zn-SOD activity was increased markedly in patients compared
to the young controls and reached a peak on the d 5 of the disease, whereas the catalase activity of the patients on d 3 and
d 5 were in the normal range, but higher on d 10. The enzyme activities of the elderly group were generally increased compared
to the young controls. Copper and zinc concentrations showed corresponding alterations. These findings suggested that the
effects of oxidative stress in CVA might be reflected in red cell and plasma parameters.
Presented at the III International Congress of Pathophysiology, Lahti, Finland, 28 June–3 July, 1998. 相似文献
144.
Extracellular proteases produced by Scytalidium thermophilum, grown on microcrystalline cellulose, were most active at pH 6.5–8 and 37–45 °C when incubated for 60 min. Highest protease activity was at day 3 where endoglucanase activity was low. Protease activity measurements with and without the protease inhibitors, p-chloromercuribenzoate, PMSF, antipain, E-64, EDTA and pepstatin A, suggest production of thiol-containing serine protease and serine proteases. Endoglucanase and Avicel-adsorbable endoglucanase activity in culture medium was not significantly affected by protease inhibitors. 相似文献
145.
Ferah Budak S. Haldun Bal Gulcin Tezcan Furkan Guvenc E. Halis Akalin Guher Goral Gunnur Deniz H. Barbaros Oral 《PloS one》2016,11(11)
Although our knowledge about Brucella virulence factors and the host response increase rapidly, the mechanisms of immune evasion by the pathogen and causes of chronic disease are still unknown. Here, we aimed to investigate the immunological factors which belong to CD8+ T cells and their roles in the transition of brucellosis from acute to chronic infection. Using miRNA microarray, more than 2000 miRNAs were screened in CD8+ T cells of patients with acute or chronic brucellosis and healthy controls that were sorted from peripheral blood with flow cytometry and validated through qRT-PCR. Findings were evaluated using GeneSpring GX (Agilent) 13.0 software and KEGG pathway analysis. Expression of two miRNAs were determined to display a significant fold change in chronic group when compared with acute or control groups. Both miRNAs (miR-126-5p and miR-4753-3p) were decreased (p <0.05 or fold change > 2). These miRNAs have the potential to be the regulators of CD8+ T cell-related marker genes for chronic brucellosis infections. The differentially expressed miRNAs and their predicted target genes are involved in MAPK signaling pathway, cytokine-cytokine receptor interactions, endocytosis, regulation of actin cytoskeleton, and focal adhesion indicating their potential roles in chronic brucellosis and its progression. It is the first study of miRNA expression analysis of human CD8+ T cells to clarify the mechanism of inveteracy in brucellosis. 相似文献
146.
147.
Mustafa Durmuş Ali Rıza Kosker Yeşim Ozogul Mehmet Aydin Yılmaz UÇar Deniz Ayas 《人类与生态风险评估》2018,24(3):731-742
The effects of seasonal and sexual differences on the levels of macro, trace element, and toxic metal levels in Mullus barbatus were investigated using the ICP-MS. The quantity relationships of macro elements were found as K>P>Na>Ca>Mg for male, P>K>Na>Ca>Mg in female; the quantity relationships of trace elements were determined as Fe>Zn>Mn>Mo>Se>Cu>Ni>Co in male, Fe>Zn>Mn>Se>Cu>Ni>Mo>Co in female; and the quantity relationship of toxic elements were found as As>Pb>Cd in both male and female. Macro, trace, and toxic metal levels showed no significant differences (p > .05) in terms of sexuality, but demonstrated seasonal differences (p > .05). Overall, the highest level of macro elements was determined in the autumn, while the high level of trace elements was measured in the winter. The As, Cd, and Pb levels in the muscle tissue of red mullet fish were higher than acceptable limits. However, when the Estimated Daily Intake (EDI) and Estimated Weekly Intake (EWI) of both toxic metals are considered, they appear to be below acceptable limits. As a result, it was determined that the red mullet had been contaminated with toxic metals (Cd and Pb) but their levels according to EDI and EWI were below the limit. 相似文献
148.
149.
Muhammet Serhat Özaslan Yeliz Demir Hatice Esra Aslan Şükrü Beydemir Ömer İrfan Küfrevioğlu 《Journal of biochemical and molecular toxicology》2018,32(5)
Glutathione S‐transferases (GSTs) are the superfamily of multifunctional detoxification isoenzymes and play an important role in cellular signaling. In the present study, potential inhibition effects of chalcones were tested against human GST. For this purpose, GST was purified from human erythrocytes with 5.381 EU?mg?1 specific activity and 51.95% yield using a GSH–agarose affinity chromatographic method. The effects of chalcones on in vitro GST activity were tested at various concentrations. Ki constants of chalcones were found in the range of 7.76–41.93 μM. According to the results, 4‐fluorochalcone showed a better inhibitory effect compared with the other compounds. The inhibition mechanisms of 2'‐hydroxy‐4‐methoxychalcone and 4‐methoxychalcone were noncompetitive, whereas the inhibition mechanisms of 4'‐ hydroxychalcone, 4‐ fluorochalcone, and 4,4'‐ diflurochalcone were competitive. 相似文献
150.