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131.
We investigated the effects of colchicine on oxidative stress and Ca2+ release in serum and polymorphonuclear leucocytes (PMNs) of Familial Mediterranean Fever (FMF) patients with attack, remission
and unremission periods. Eighteen FMF patients and six age-matched healthy subjects in four groups were used. The first group
was a control. The second group included patients with active FMF. The third and fourth groups were patients with remission
and unremission, respectively. Colchicine (1.5 mg/day) was given to the third and fourth groups for 1 month. PMN cells, serum
lipid peroxidation and intracellular Ca2+-release levels in the attack and unremission groups were higher than in those in controls, although they were lower in the
remission group than in the attack group. Serum vitamin E and β-carotene concentrations were higher in the remission group
than in the control and attack groups. However, PMN, serum lipid peroxidation and Ca2+-release levels were further increased in the unremission group compared to the attack group. Glutathione peroxidase, reduced
glutathione and vitamin A values in the four groups did not change by FMF and colchicine. In conclusion, we observed that
colchicine induced protective effects on oxidative stress by modulating vitamin E, β-carotene and Ca2+-release levels in FMF patients with a remission period. 相似文献
132.
Nazıroğlu M 《Neurochemical research》2011,36(3):355-366
The Na+ and Ca2+-permeable melastatin related transient receptor potential 2 (TRPM2) channels can be gated either by ADP-ribose (ADPR) in
concert with Ca2+ or by hydrogen peroxide (H2O2), an experimental model for oxidative stress, binding to the channel’s enzymatic Nudix domain. Since the mechanisms that
lead to TRPM2 gating in response to ADPR and H2O2 are not understood in neuronal cells, I summarized previous findings and important recent advances in the understanding of
Ca2+ influx via TRPM2 channels in different neuronal cell types and disease processes. Considering that TRPM2 is activated by
oxidative stress, mediated cell death and inflammation, and is highly expressed in brain, the channel has been investigated
in the context of central nervous system. TRPM2 plays a role in H2O2 and amyloid β-peptide induced striatal cell death. Genetic variants of the TRPM2 gene confer a risk of developing Western
Pacific amyotropic lateral sclerosis and parkinsonism-dementia complex and bipolar disorders. TRPM2 also contributes to traumatic
brain injury processes such as oxidative stress, inflammation and neuronal death. There are a limited number of TRPM2 channel
blockers and they seem to be cell specific. For example, ADPR-induced Ca2+ influx in rat hippocampal cells was not blocked by N-(p-amylcinnomoyl)anthralic acid (ACA), the IP3 receptor inhibitor 2-aminoethoxydiphenyl borate or PLC inhibitor flufenamic acid (FFA). However, the Ca2+ entry in rat primary striatal cells was blocked by ACA and FFA. In conclusion TRPM2 channels in neuronal cells can be gated
by either ADPR or H2O2. It seems to that the exact relationship between TRPM2 channels activation and neuronal cell death still remains to be determined. 相似文献
133.
Kazuhito Tsuboi Tatsuya Tai Ryouhei Yamashita Hanif Ali Takashi Watanabe Toru Uyama Yoko Okamoto Keisuke Kitakaze Yasuhiro Takenouchi Shinji Go Iffat Ara Sonia Rahman Hitoshi Houchi Tamotsu Tanaka Yasuo Okamoto Akira Tokumura Junko Matsuda Natsuo Ueda 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2021,1866(9):158972
Bioactive N-acylethanolamines (NAEs) include palmitoylethanolamide, oleoylethanolamide, and anandamide, which exert anti-inflammatory, anorexic, and cannabimimetic actions, respectively. The degradation of NAEs has been attributed to two hydrolases, fatty acid amide hydrolase and NAE acid amidase (NAAA). Acid ceramidase (AC) is a lysosomal enzyme that hydrolyzes ceramide (N-acylsphingosine), which resembles NAAA in structure and function. In the present study, we examined the role of AC in the degradation of NAEs. First, we demonstrated that purified recombinant human AC can hydrolyze various NAEs with lauroylethanolamide (C12:0-NAE) as the most reactive NAE substrate. We then used HEK293 cells metabolically labeled with [14C]ethanolamine, and revealed that overexpressed AC lowered the levels of 14C-labeled NAE. As analyzed with liquid chromatography-tandem mass spectrometry, AC overexpression decreased the amounts of different NAE species. Furthermore, suppression of endogenous AC in LNCaP prostate cells by siRNA increased the levels of various NAEs. Lastly, tissue homogenates from mice genetically lacking saposin D, a presumable activator protein of AC, showed much lower hydrolyzing activity for NAE as well as ceramide than the homogenates from wild-type mice. These results demonstrate the ability of AC to hydrolyze NAEs and suggest its physiological role as a third NAE hydrolase. 相似文献
134.
Fusun Eroglu Lutfi Yavuz Berit G. Ceylan Funda Yılmaz Erol Eroglu Namik Delibas Mustafa Nazıroğlu 《Cell biochemistry and function》2010,28(3):211-216
It has been well known that some volatile anesthetic agents produce oxidative stress. Desflurane as a new volatile agent might have limited oxidative toxic effect because it is relatively a new short‐acting anesthetic characterized by a short duration of action and a quick postanesthetic recovery. We investigated effect of desflurane on serum glutathione peroxidase (GSH‐Px), lipid peroxidation (LP), vitamin E, and erythrocyte superoxide dismutase (SOD) values in patients. Fifteen adult patients are scheduled for elective surgery, ASA I or II physical status. Tidal volume and ventilation frequency were kept unchanged during the operation. Baseline values in venous blood samples were preoperatively taken and blood was also taken postoperatively at the 1st and the 12th hours of desflurane exposure. LP levels were significantly (p < 0.05) higher postoperatively at 1st hour than in preoperative values while α‐tocopherol concentration was significantly (p < 0.001) lower in postoperative period at 1st hour than in preoperative period. Erythrocyte SOD and serum GSH‐Px activities did not differ between pre‐ and postoperative periods. In conclusion, we observed that desflurane produced oxidative stress by decreasing α‐tocopherol levels. Use of vitamin E may be possible to reduce the oxidative effect of desflurane. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
135.
Manual offline analysis, of a scanning electron microscopy (SEM) image, is a time consuming process and requires continuous human intervention and efforts. This paper presents an image processing based method for automated offline analyses of SEM images. To this end, our strategy relies on a two-stage process, viz. texture analysis and quantification. The method involves a preprocessing step, aimed at the noise removal, in order to avoid false edges. For texture analysis, the proposed method employs a state of the art Curvelet transform followed by segmentation through a combination of entropy filtering, thresholding and mathematical morphology (MM). The quantification is carried out by the application of a box-counting algorithm, for fractal dimension (FD) calculations, with the ultimate goal of measuring the parameters, like surface area and perimeter. The perimeter is estimated indirectly by counting the boundary boxes of the filled shapes. The proposed method, when applied to a representative set of SEM images, not only showed better results in image segmentation but also exhibited a good accuracy in the calculation of surface area and perimeter. The proposed method outperforms the well-known Watershed segmentation algorithm. 相似文献
136.
Author self-citation in the general medicine literature 总被引:1,自引:0,他引:1
Background
Author self-citation contributes to the overall citation count of an article and the impact factor of the journal in which it appears. Little is known, however, about the extent of self-citation in the general clinical medicine literature. The objective of this study was to determine the extent and temporal pattern of author self-citation and the article characteristics associated with author self-citation.Methodology/Principal Findings
We performed a retrospective cohort study of articles published in three high impact general medical journals (JAMA, Lancet, and New England Journal of Medicine) between October 1, 1999 and March 31, 2000. We retrieved the number and percentage of author self-citations received by the article since publication, as of June 2008, from the Scopus citation database. Several article characteristics were extracted by two blinded, independent reviewers for each article in the cohort and analyzed in multivariable linear regression analyses. Since publication, author self-citations accounted for 6.5% (95% confidence interval 6.3–6.7%) of all citations received by the 328 articles in our sample. Self-citation peaked in 2002, declining annually thereafter. Studies with more authors, in cardiovascular medicine or infectious disease, and with smaller sample size were associated with more author self-citations and higher percentage of author self-citation (all p≤0.01).Conclusions/Significance
Approximately 1 in 15 citations of articles in high-profile general medicine journals are author self-citations. Self-citation peaks within about 2 years of publication and disproportionately affects impact factor. Studies most vulnerable to this effect are those with more authors, small sample size, and in cardiovascular medicine or infectious disease. 相似文献137.
Acne vulgaris is the one of the most common skin diseases. Although isotretinoin (13-cis-retinoic acid) is an effective and well-tolerated medication, it has a wide range of side effects. Because the effects of isotretinoin on oxidant and antioxidant systems have not yet been clarified, we investigated plasma and erythrocyte antioxidant vitamins, lipid peroxidation (LP), reduced glutathione (GSH) and glutathione peroxidase (GSH-Px) values in patients with acne vulgaris before and after isotretinoin treatment. The study was performed on the blood plasma and erythrocytes of 31 acne vulgaris patients. Blood samples were taken from the patients before treatment and after isotretinoin (oral and 0·5-0·7?mg·kg(-1) ) treatment for 2?months. Plasma amtioxidant vitamins, erythrocyte malondialdehyde, GSH and GSH-Px levels were measured. Plasma vitamin E (p?0·001), lipid peroxidation (LP) and serum high-density lipoprotein cholesterol (p?0·001) values were significantly lower in the treatment group than in the pre-treatment group, although erythrocyte LP (p?0·001), GSH (p?0·01) and GSH-Px (p?0·001), aspartate aminotransferase (p?0·05), alanine aminotransferase (p?0·05), density lipoprotein cholesterol (p?0·001) and total cholesterol (p?0·01) levels were significantly higher in the treatment group than in the pre-treatment group. Vitamins A, C and β-carotene concentrations did not change significantly between the two groups. In conclusion, the results of the current study indicate that isotretinoin treatment induces oxidative stress and liver damage by decreasing plasma vitamin E and increasing erythrocytes GSH-Px, GSH and liver enzyme values. Copyright ? 2012 John Wiley & Sons, Ltd. 相似文献
138.
A putative β-glucosidase gene from the genome of Bacillus halodurans C-125 was expressed in E. coli under the regulation of T7lac promoter. On induction with isopropyl-β-D-1-thiogalactopyranoside, the enzyme expressed at ∼40% of the cell protein producing
238 mg/liter culture. With increase in culture cell density to A
600 12 in auto-inducing M9NG medium, β-glucosidase production increased 3-fold. Approximately 70% of the expressed enzyme was
in a soluble form, while the rest was in an insoluble fraction of the cell lysate. The soluble and active form of the expressed
enzyme was purified by ammonium sulfate precipitation followed by ion-exchange chromatography to a purity >98%. The mass of
the enzyme as determined by MALDI-TOF mass spectrometry was 51,601 Da, which is nearly the same as the calculated value. Phylogenetic
analysis of the β-glucosidase of B. halodurans was found to cluster with members of the genus Bacillus. Temperature and pH optima of the enzyme were found to be 45°C and 8.0, respectively, under the assay conditions. K
m and k
cat against p-nitrophenyl-β-D-glucopyranoside were 4 mM and 0.75 sec−1, respectively. To our knowledge, this is the first report of high-level expression and characterization of a β-glucosidase
from B. halodurans. 相似文献
139.
Antibodies to sperm surface fertilization antigen (FA-1): their specificities and site of interaction with sperm in male genital tract 总被引:1,自引:0,他引:1
The fertilization antigen (FA-1) isolated from murine testes demonstrated its dimeric form of 49,000 +/- 2,000 molecular weight (M.W.) or a monomer of 23,000 M.W. on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The FA-1 was immunogenic in all three female rabbits tested and raised a high-titer antisera [enzyme-linked immunosorbent assay (ELISA) titers; 1:1,024 to 1:4,096]. The rabbit anti-FA-1 antisera predominantly recognized the dimeric form of 49,000 +/- 2,000 M.W. on the Western blot of lithium diiodosalicylate (LIS)-solubilized murine testes. None of the antisera reacted with any somatic tissue, indicating germ-cell specificity of FA-1. To determine the cellular localization of the immunoreactive FA-1, a novel ultrasensitive immunogold-silver staining (IGSS) procedure was developed. The anti-FA-1-IgG showed intense staining in the luminal region of the seminiferous tubules containing spermatids and spermatozoa. No reaction was observed in the peripheral area of the tubules containing Sertoli cells, spermatogonia, leptotene, and zygotene spermatocytes. The biodistribution studies of 125I-labeled anti-FA-1 IgG in mice revealed that the antibodies do not bind to somatic tissues such as blood cell, liver, heart, kidney, muscle, and gastrointestinal tissue and do not transudate into testes and seminal vesicle. However, the antibodies preferentially transudate into epididymis (especially corpus or cauda regions) and vas deferens to bind to sperm cells. In conclusion, our data indicate that FA-1 can induce an immune response that is germ cell-specific, directed against later stages of spermatogenesis. The antibodies to FA-1 interact with sperm after penetration through epididymis (especially corpus and cauda regions) and vas deferens rather than through testes and seminal vesicles. 相似文献
140.
Muhsin Naz Sinan Uyanik M. Irfan Yesilnacar Erkan Sahinkaya 《Ecological Engineering》2009,35(8):1255-1263
A horizontal subsurface flow (HSSF) and a free water surface flow (FWSF) constructed wetlands (4 m2 of each) were set up on the campus of Harran University, Sanliurfa, Turkey. The main objective of the research was to compare the performance of two systems to decide the better one for future planning of wastewater treatment system on the campus. Both of the wetland systems were planted with Phragmites australis and Canna indica. During the observation period (10 months), environmental conditions such as pH, temperature and total chemical oxygen demand (COD), soluble COD, total biochemical oxygen demand (BOD), soluble BOD, total suspended solids (TSS), total phosphate (TP), total nitrogen (TN) removal efficiencies of the systems were determined. According to the results, average yearly removal efficiencies for the HSSF and the FWSF, respectively, were as follows: total COD (75.7% and 69.9%), soluble COD (85.4% and 84.3%), total BOD (79.6% and 87.6%), soluble BOD (87.7% and 95.3%), TN (33.2% and 39.4%), and TP (31.5% and 6.5%). Soluble COD and BOD removal efficiencies of both systems increased gradually since the start-up. After nine months of operation, above 90% removal of organic matters were observed. The treatment performances of the HSSF were better than that of the FWSF with regard to the removal of suspended solids and total COD at especially high temperatures. In FWSF systems, COD concentrations extremely exceeded the discharge limit values due to high concentrations of algae in spring months.The performance of the two systems was modelled using an artificial neural network-back-propagation algorithm. The ANN model was competent at providing reasonable match between the measured and the predicted concentrations of total COD (R = 0.90 for HSSF and R = 0.96 for FWSF), soluble COD (R = 0.90 for HSSF and R = 0.74 for FWSF) and total BOD (R = 0.94 for HSSF and R = 0.84 for FWSF) in the effluents of constructed wetlands. 相似文献