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41.
Interleukin (IL)-6 is produced at the site of inflammation and plays a key role in the acute phase response as defined by a variety of clinical and biological features such as the production of acute phase proteins. IL-6 in combination with its soluble receptor sIL-6Ralpha, dictates the transition from acute to chonic inflammation by changing the nature of leucocyte infiltrate (from polymorphonuclear neutrophils to monocyte/macrophages). In addition, IL-6 exerts stimulatory effects on T- and B-cells, thus favoring chronic inflammatory responses. Strategies targeting IL-6 and IL-6 signaling led to effective prevention and treatment of models of rheumatoid arthritis and other chronic inflammatory diseases.  相似文献   
42.
Molecular Biology Reports - Etiopathogenesis of acquired and congenital cholesteatoma is still unclear. The clinical behavior of adult acquired, pediatric acquired and congenital cholesteatomas...  相似文献   
43.
Amsonia orientalis Decne. (Apocynaceae), is a rare and threatened plant species which is located only in a constricted area in northeast of Greece and northwest of Turkey in the world. Although phylogenetic analysis depending on nucleotide sequences of genes from different sources (nucleus, mitochondria and chloroplast) became a major tool for classification of plant species, there is still a big lack of information about A. orientalis in the international molecular data bases such as NCBI. In the current study, we phylogenetically analyzed three commonly used molecular markers (18S rDNA, 18S-28S rDNA-ITS region and trnL-F intergenic spacer) from A. orientalis samples collected from Turkey to determine the genetic diversity and also to question the systematic position of A. orientalis. As a result, A. orientalis samples clearly showed close relation with Alyxieae tribe rather than Vinceae. And this result brings the necessity to reconsider the morphological characters that have used to delimit the tribes of Rauvolfioideae.  相似文献   
44.
Caulerpa taxifolia is one of the most important and best-studied alien species in the Mediterranean Sea. The present study reveals the macrobenthic assemblages associated with C. taxifolia from the region. We found 26 species from Polychaeta, 31 species from Crustacea, 22 species from Mollusca and 5 species from Echinodermata. In conclusion, C. taxifolia in İskenderun Bay can be considered an ecosystem engineer that modifies local habitats and also enhances biodiversity.  相似文献   
45.
46.
AIM: Behçet''s disease (BD) is an inflammatory vasculitis with immunologic, endothelial and neutrophil alterations. Adenosine deaminase (AD) is a marker of T-cell activation and is related to the production of reactive oxygen species by neutrophils with the production of NO(*), O(2)(*-), H(2)O(2) and OH(*). We reported increased tumour necrosis factor-alpha, soluble interleukin-2 receptor, interleukin-6, interleukin-8 and NO(*) in active BD. As there is a relation between cytokines, T cells and oxidative stress in inflammatory diseases, this study further evaluated: (1) plasma AD activity and its correlation with acute phase reactants; (2) thiobarbituric acid-reactive substances (TBARS) as an indicator for lipid peroxidation; and (3) antioxidant enzymes superoxide dismutase (SOD), glutathione peroxidase (GSHPx) and catalase in patients with BD. The effect of disease activity and correlations between the measured parameters were explored. METHODS: A total of 35 active (n=17) or inactive (n=18) patients with BD (16 men, 19 women) satisfying International Study Group criteria, and 20 age-matched and sex-matched controls (nine men, 11 women) were included in this cross-sectional case-control study. AD and TBARS were measured in plasma, catalase in red blood cells (RBC), and SOD and GSHPx in both plasma and RBC in both groups. Acute phase reactants (alpha(1)-antitrypsin, alpha(2)-macroglobulin, neutrophils, erythrocyte sedimentation rate) were used to classify patients as active or inactive. RESULTS: Plasma AD (mean+/-standard error of the mean, 36.1+/-0.7 U/l) and TBARS (4.2+/-0.1 nmol/ml) levels were significantly (for each, p<0.001) higher in BD than in controls (24.1+/-0.8 U/l and 1.6+/-0.1 nmol/ml, respectively). RBC catalase activity was significantly (p<0.001) lower in BD than in controls (120.9+/-3.8 versus 160.3+/-4.1 k/g haemoglobin). SOD and GSHPx activities were significantly lower in both plasma and erythrocytes of patients with BD than in controls (plasma SOD, 442.4+/-8.6 versus 636.4+/-9.2 U/ml, p<0.001; RBC SOD, 3719.2+/-66.0 versus 4849.7+/-49.0 U/g haemoglobin, p<0.001; plasma GSHPx, 73.1+/-1.5 versus 90.6+/-2.9 U/ml, p<0.001; RBC GSHPx, 600.7+/-8.0 versus 670.6+/-10.1 U/g haemoglobin, p<0.001). Active BD patients had significantly lower antioxidant enzymes (except RBC catalase) and higher AD and TBARS levels than inactive subjects (for each, p<0.01). When considering all BD patients, a significant positive correlation was present between AD and TBARS (p<0.001) whereas both AD and TBARS were negatively correlated with antioxidant enzymes (for each, p<0.05). CONCLUSIONS: AD and lipid peroxidation are increased and associated with defective antioxidants in BD, suggesting interactions between activated T cells and neutrophil hyperfunction. Measures of pro-oxidative stress and antioxidative defence with AD activity as an indicator of T-cell activation can be considered as significant supportive diagnostic indicators, especially in active disease. In addition, strengthening the antioxidant defence may contribute to treatment modalities.  相似文献   
47.
An essential step in the discovery of molecular mechanisms contributing to disease phenotypes and efficient experimental planning is the development of weighted hypotheses that estimate the functional effects of sequence variants discovered by high-throughput genomics. With the increasing specialization of the bioinformatics resources, creating analytical workflows that seamlessly integrate data and bioinformatics tools developed by multiple groups becomes inevitable. Here we present a case study of a use of the distributed analytical environment integrating four complementary specialized resources, namely the Lynx platform, VISTA RViewer, the Developmental Brain Disorders Database (DBDB), and the RaptorX server, for the identification of high-confidence candidate genes contributing to pathogenesis of spina bifida. The analysis resulted in prediction and validation of deleterious mutations in the SLC19A placental transporter in mothers of the affected children that causes narrowing of the outlet channel and therefore leads to the reduced folate permeation rate. The described approach also enabled correct identification of several genes, previously shown to contribute to pathogenesis of spina bifida, and suggestion of additional genes for experimental validations. The study demonstrates that the seamless integration of bioinformatics resources enables fast and efficient prioritization and characterization of genomic factors and molecular networks contributing to the phenotypes of interest.  相似文献   
48.
Sepsis is known to be associated with oxidative stress. Novel markers of oxidative stress are now believed to be F2-isoprostanes which are produced in situ in phospholipids and subsequently released into circulation and excreted in the urine. This study, therefore, sought to investigate whether the excretion of the isoprostane, 8-iso-PGF(2 alpha), is elevated during sepsis. The excretion of 8-iso-PGF(2 alpha), in the 24 h urine of three patients was studied in the septic stage, during mobilisation and in the state of health by a radioimmunological method. Extrapolating the urinary excretion of 8-iso-PGF(2 alpha) over time showed an insignificant variation in the excretion values during 24 h. The amount of mean 24 h urinary 8-iso-PGF(2 alpha) was about similar in the septic stage and in the state of health but increased remarkably during mobilisation in two of the patients. We suggest that mobilisation of septic patients can be associated with an increase of oxidative stress which may stem from an increase in oxygen consumption and/or from a depletion of antioxidants leading to the enhanced formation of free radicals.  相似文献   
49.
The first record of Ferosagitta galerita in the MediterraneanChaetognatha fauna is reported. The morphological and ecologicalfeatures of this species, which was hitherto only known to livenear Madagascar in the Indian Ocean, are given in detail. Withthis new finding, the number of chaetognath species to be knownin the Mediterranean Sea is increased.  相似文献   
50.
The aim of the present study was to investigate whether iron, which is involved in the formation of free radicals in vitro, can initiate cellular injury in human intestinal cells. The effects of various concentrations of iron were studied in preconfluent, colonic-cancerogenous cells, and also in postconfluent, differentiating cells. Cellular damage was assessed using cell proliferation (serial cell counting), tetrazolium dye (MTT) uptake, lactate dehydrogenase (LDH) release and apoptosis studies based on caspase-3 activities. Also the activities of the major antioxidative enzymes, superoxide dismutase (SOD), catalase and glutathione peroxidase (GPx) were measured after the cells had been exposed to iron. Our results indicated that preconfluent cells were more susceptible to iron toxicity, as assessed by a significant reduction in cell proliferation and MTT uptake in a concentration-dependent manner compared to the control. However, no evidence for MTT uptake was observed in postconfluent cells. Caspase-3 activity, an indicator of cell apoptosis, considerably increased in preconfluent cells at high iron levels compared to the control (p < 0.05), whereas postconfluent cells were not significantly affected. LDH release was similar for both groups and was significantly higher than the control at 900 microM iron and above. SOD activities were not affected by iron in either group, whereas GPx was considerably higher in iron-treated cells in both groups compared with the control (because of relatively high standard deviations this effect was not significant). In conclusion we suggest that iron exerts its toxic effects intracellularly especially in preconfluent Caco-2 cells, whereas only high iron doses were able to alter the viability of differentiating, enterocyte-like cells.  相似文献   
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