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101.
Examination of Changes in Enzyme Activities of Erythrocyte Glucose 6‐Phosphate Dehydrogenase and 6‐Phosphogluconate Dehydrogenase in Rats Given Naringenin and Lead Acetate
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Ramazan Demirdag Veysel Comakli Ahmet Ozkaya Zafer Sahin Uzeyir Dag Emrah Yerlikaya Muslum Kuzu 《Journal of biochemical and molecular toxicology》2015,29(1):43-47
In our study, controlled experimental groups were performed by giving substances Lead acetate, Naringenin and Naringenin + Lead acetate to rats in vivo conditions Changes in the glucose 6‐phosphate dehydrogenase (G6PD) and 6‐phosphogluconate dehydrogenase (6PGD) enzyme activities in erythrocytes of rats in these groups were compared to the Control group. An inhibition significant degree for G6PD enzyme activity was observed in all groups when compared to the Control group (p < 0.001). While inhibition significant degree for 6PGD enzyme activity was observed in Lead acetate groups (p < 0.001), no significant effect was observed in the Naringenin and Naringenin + Lead acetate groups (p > 0.05). In addition, lead levels in the groups of rats were determined using an inductively coupled plasma mass spectrometer (ICP‐MS) device. As a result of measurements by the ICP‐MS device, lead levels were found as an average of 42.9 ± 2.51, 36.71 ± 1.13, 172.16 ± 9.63, and 95.07 ± 5.87 ppm in the Control, Naringenin, Lead acetate and Naringenin + Lead acetate groups, respectively. Our results were shown that Naringenin has protective effects on the Lead acetate induced oxidative stress erythrocytes in rat. 相似文献
102.
103.
The aim of this study is to investigate in vitro antimicrobial and antioxidant activities of the methanol extracts of Parmelia saxatilis (L) Ach., Platismatia glauca (L.) W.L. Club. & C.F. Culb., Ramalina pollinaria (Wesstr.) Ach., Ramalina polymorpha (Liljeblad) Ach. and Umbilicaria nylanderiana (Zahlbr.) H. Magn. Antioxidant activity was evaluated by two separate methods: scavenging of free radical DPPH and the inhibition of linoleic acid oxidation. Extracts of Parmelia saxatilis, Platismatia glauca., Ramalina pollinaria and Ramalina polymorpha did not exert any activity in both assays, whereas those of Umbilicaria nylanderiana provided 50% inhibition at 400.2 microg/ml concentration in the former and gave 53% inhibition at 2g/l concentration. Total phenolic constituents of extracts from lichen species tested (P. saxatilis, P. glauca, R. pollinaria, R. polymorpha and U. nylanderiana) were 1.0% (w/w), 1.1% (w/w), 1.0% (w/w), 0.8% (w/w) and (3.0% w/w), respectively (as gallic acid equivalent); implying that the observed activity could be related to the amount of polar phenolics. Extracts were also found to possess antimicrobial activity against some test bacteria and fungi and yeast. 相似文献
104.
105.
Manar M. Alnema Suleyman Aydin Yusuf Ozkan Adile F. Dagli Hanifi İ. Ozercan Nezahat Yildirim İbrahim Sahin Aziz Karaoglu Nermin Kilic Mustafa Yilmaz Mehmet R. Ozercan Emir Donder 《Molecular and cellular biochemistry》2010,339(1-2):173-179
The underlying molecular mechanism of carcinogenesis in oral squamous cell carcinoma (OSCC) is poorly understood and appears to be controlled on many genetic, environmental, and hormonal factors. Obestatin and ghrelin, two recently discovered hormones, are co-expressed in endocrine cells. The purpose of this investigation was to examine the immunohistochemical features of OSCCs in relation to the tissue concentration of ghrelin and obestatin. The association between OSCC and Epstein Barr Virus (EBV) status was also explored. The expression of ghrelin and obestatin was examined by immunohistochemistry and immunoassay in oral biopsy specimens: 10 benign squamous epithelial cell samples, 10 microinvasive squamous cell carcinomas, and seven well-differentiated and seven poorly differentiated OSCCs. The presence of EBV was evaluated in these samples using immunohistochemistry. The concentrations of ghrelin and obestatin in tissue homogenates were measured by RIA and ELISA, respectively. Squamous cell carcinomas and benign tissue samples were positive for anti-EBV antibody, and obestatin and ghrelin were shown to be co-expressed in all stratified squamous epithelium samples. Expression of ghrelin and obestatin was decreased or absent in OSCCs in relation to the invasiveness of the carcinoma; ghrelin and obestatin levels in cancerous tissue homogenates were lower than in benign tissue homogenates. These results indicate that the concentrations and distribution of immunoreactive obestatin and ghrelin might be helpful in distinguishing OSCC from benign tumors. Maintaining normal levels of these hormones might be required for regulation of normal cell division. However, detailed studies will be required for better understanding of the complex mechanism of carcinogenesis relating to OSCCs. 相似文献
106.
Heiko A Mannsperger Stefan Uhlmann Christian Schmidt Stefan Wiemann Özgür Sahin Ulrike Korf 《Proteome science》2010,8(1):69
Background
Reverse phase protein arrays (RPPA) have been demonstrated to be a useful experimental platform for quantitative protein profiling in a high-throughput format. Target protein detection relies on the readout obtained from a single detection antibody. For this reason, antibody specificity is a key factor for RPPA. RNAi allows the specific knockdown of a target protein in complex samples and was therefore examined for its utility to assess antibody performance for RPPA applications. 相似文献107.
Generation of tissue-specific and promiscuous HLA ligand databases using DNA microarrays and virtual HLA class II matrices. 总被引:12,自引:0,他引:12
T Sturniolo E Bono J Ding L Raddrizzani O Tuereci U Sahin M Braxenthaler F Gallazzi M P Protti F Sinigaglia J Hammer 《Nature biotechnology》1999,17(6):555-561
Most pockets in the human leukocyte antigen-group DR (HLA-DR) groove are shaped by clusters of polymorphic residues and, thus, have distinct chemical and size characteristics in different HLA-DR alleles. Each HLA-DR pocket can be characterized by "pocket profiles," a quantitative representation of the interaction of all natural amino acid residues with a given pocket. In this report we demonstrate that pocket profiles are nearly independent of the remaining HLA-DR cleft. A small database of profiles was sufficient to generate a large number of HLA-DR matrices, representing the majority of human HLA-DR peptide-binding specificity. These virtual matrices were incorporated in software (TEPITOPE) capable of predicting promiscuous HLA class II ligands. This software, in combination with DNA microarray technology, has provided a new tool for the generation of comprehensive databases of candidate promiscuous T-cell epitopes in human disease tissues. First, DNA microarrays are used to reveal genes that are specifically expressed or upregulated in disease tissues. Second, the prediction software enables the scanning of these genes for promiscuous HLA-DR binding sites. In an example, we demonstrate that starting from nearly 20,000 genes, a database of candidate colon cancer-specific and promiscuous T-cell epitopes could be fully populated within a matter of days. Our approach has implications for the development of epitope-based vaccines. 相似文献
108.
A Yildirim Y N Sahin H Suleyman A Yilmaz S Yildirim 《Journal of physiology and pharmacology》2007,58(1):105-116
It has been believed that overproduction of free radicals and/or deficiency of antioxidant systems, and stress hormones may play a role in etiopathogenesis of many diseases, including gastric ulcer. This study evaluated whether there was an effect of adrenalectomy on lipid peroxidation [malondialdehyde (MDA)] and antioxidant [superoxide dismutase (SOD), glutathione peroxidase (GPX) and glutathione (GSH) levels] systems in gastric tissue and erythrocyte in rats. As well, the impacts of administration of prednisolone and epinephrine on these systems in adrenalectomized rats were investigated. Thirty-three rats were randomly grouped as sham-operated (group I), adrenalectomized (group II), adrenalectomized + prednisolone (group III) and adrenalectomized + epinephrine (group IV). After experimental procedures, blood and gastric tissues samples were taken from each animal in all groups. Colorimetric assays were employed to determine gastric tissue and erythrocyte levels of MDA and GSH, and SOD and GPX activities. Adrenalectomy in group II rats caused a marked decrease of SOD and GPX activities and MDA levels, and an increase of GSH levels in gastric tissue and erythrocyte, when compared to sham-operated rats. However, especially epinephrine injection after adrenalectomy resulted in a significantly increase of measured antioxidant enzyme activities and GSH levels in both gastric tissue and erythrocyte. These results indicate that adrenalectomy appeared to alter the levels of antioxidants and lipid peroxidation product in gastric tissue and erythrocyte. Thus, the present study provides a physiological regulatory role of adrenal gland in the maintenance of oxidant/antioxidant balance in gastric tissue and erythrocyte. 相似文献
109.
110.
Using laboratory challenge experiments, we examined whether Campylobacter-specific maternal antibody (MAB) plays a protective role in young chickens, which are usually free of Campylobacter under natural production conditions. Kinetics of C. jejuni colonization were compared by infecting 3-day-old broiler chicks, which were naturally positive for Campylobacter-specific MAB, and 21-day-old broilers, which were negative for Campylobacter-specific MAB. The onset of colonization occurred much sooner in birds challenged at the age of 21 days than it did in the birds inoculated at 3 days of age, which suggested a possible involvement of specific MAB in the delay of colonization. To further examine this possibility, specific-pathogen-free layer chickens were raised under laboratory conditions with or without Campylobacter infection, and their 3-day-old progenies with (MAB(+)) or without (MAB(-)) Campylobacter-specific MAB were orally challenged with C. jejuni. Significant decreases in the percentage of colonized chickens were observed in the MAB(+) group during the first week compared with the MAB(-) group. These results indicate that Campylobacter-specific MAB plays a partial role in protecting young chickens against colonization by C. jejuni. Presence of MAB in young chickens did not seem to affect the development of systemic immune response following infection with C. jejuni. However, active immune responses to Campylobacter occurred earlier and more strongly in birds infected at 21 days of age than those infected at 3 days of age. Clearance of Campylobacter infection was also observed in chickens infected at 21 days of age. Taken together, these findings (i) indicate that anti-Campylobacter MAB contributes to the lack of Campylobacter infection in young broiler chickens in natural environments and (ii) provide further evidence supporting the feasibility of development of immunization-based approaches for control of Campylobacter infection in poultry. 相似文献