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81.
Relationship between synovial fluid and plasma manganese,arginase, and nitric oxide in patients with rheumatoid arthritis 总被引:3,自引:0,他引:3
Nitric oxide (NO) participates in the pathogenesis of inflammatory reactions in many autoimmune diseases such as rheumatoid
arthritis (RA). There is a reciprocal pathway between arginase and nitric oxide synthese (NOS) for NO production, and Mn is
required for arginase activity and stability. To investigate whether NO production related with the arginine-nitric oxide
pathway in patients with RA, we measured synovial fluid and plasma nitrite (NOx) levels, arginase activities, and its cofactor manganese (Mn) concentrations in 21 RA patients and 13 healthy control subjects.
Plasma albumin levels were measured as an index of nutritional status. NOx levels were determined after the reduction of nitrates to nitrites using the Griess reaction. Whereas, synovial fluid arginase
activities and Mn levels were found to be significantly lower (p<0.001, p<0.001, respectively), plasma arginase activities and Mn levels were similar in patients with RA when compared to the control
subjects. Plasma and synovial fluid NO levels were similar in patients with RA and in healthy subjects (p>0.05, p>0.05, respectively). There were significantly positive correlations between synovial fluid and plasma arginase activities
vs Mn content (r=0.543, p=0.011; r=0.516, p=0.017, respectively) and significantly negative correlations between synovial fluid and plasma NO levels vs arginase activities
(r=−0.497, p=0.022; r=−0.508, p=0.019 respectively) in the patients group. Our results indicate that the lower concentration of synovial fluid Mn could cause
lower arginase activity and this could also upregulate NO production by increasing L-arginine content in patients with RA. 相似文献
82.
Accuracy in assessing the distribution of soil organic carbon (SOC) is an important issue because of playing key roles in the functions of both natural ecosystems and agricultural systems. There are several studies in the literature with the aim of finding the best method to assess and map the distribution of SOC content for Europe. Therefore this study aims searching for another aspect of this issue by looking to the performances of using aggregated soil samples coming from different studies and land-uses. The total number of the soil samples in this study was 23,835 and they’re collected from the “Land Use/Cover Area frame Statistical Survey” (LUCAS) Project (samples from agricultural soil), BioSoil Project (samples from forest soil), and “Soil Transformations in European Catchments” (SoilTrEC) Project (samples from local soil data coming from six different critical zone observatories (CZOs) in Europe). Moreover, 15 spatial indicators (slope, aspect, elevation, compound topographic index (CTI), CORINE land-cover classification, parent material, texture, world reference base (WRB) soil classification, geological formations, annual average temperature, min-max temperature, total precipitation and average precipitation (for years 1960–1990 and 2000–2010)) were used as auxiliary variables in this prediction. One of the most popular geostatistical techniques, Regression-Kriging (RK), was applied to build the model and assess the distribution of SOC. This study showed that, even though RK method was appropriate for successful SOC mapping, using combined databases was not helpful to increase the statistical significance of the method results for assessing the SOC distribution. According to our results; SOC variation was mainly affected by elevation, slope, CTI, average temperature, average and total precipitation, texture, WRB and CORINE variables for Europe scale in our model. Moreover, the highest average SOC contents were found in the wetland areas; agricultural areas have much lower soil organic carbon content than forest and semi natural areas; Ireland, Sweden and Finland has the highest SOC, on the contrary, Portugal, Poland, Hungary, Spain, Italy have the lowest values with the average 3%. 相似文献
83.
Ahmet Koyuncu Fahri Çelebi Erhan Ertekin Burcu Ece Kök Raşit Tükel 《Attention deficit and hyperactivity disorders》2016,8(2):95-100
The aim of this study is to investigate the rate of childhood traumatic experiences and assess the relationship between childhood trauma and impulsivity in the presence of attention deficit–hyperactivity disorder (ADHD) in patients with social anxiety disorder (SAD). A total of 123 patients with a primary diagnosis of SAD were enrolled. All patients were assessed by using the clinical version of Structured Clinical Interview for DSM-IV (SCID-I/CV) and Schedule for Affective Disorders and Schizophrenia for School Age Children—Present and Lifetime version (K-SADS-PL), ADHD module. A clinical and sociodemographic data form and rating scales were filled out. We found higher rates of emotional traumatic experiences and impulsivity along with more severe symptoms of depression, anxiety and social anxiety in the group of SAD patients with childhood ADHD than in SAD patients without ADHD in childhood. The presence of ADHD is associated with higher severity in several domains in patients with SAD. Patients with SAD should be assessed carefully whether they have ADHD, especially when their SAD symptoms are severe, when they have a history of traumatic experiences or problems with impulse control. 相似文献
84.
Elif Yilmaz Ozmen Mehmet Sezgin Mustafa Yilmaz 《Journal of Molecular Catalysis .B, Enzymatic》2009,57(1-4):109-114
The objective of this study was to prepare cross-linked β-cyclodextrin polymers for immobilization of Candida rugosa lipase. The structures of synthesized macrocyclic compounds were characterized by Fourier transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA) and scanning electron microscope (SEM) techniques. Properties of the immobilized systems were assessed and their performance on hydrolytic reaction were evaluated and compared with the free enzyme. The influence of activation agents (glutaraldehyde (GA) and hexamethylene diisocyanate (HMDI)) and thermal and pH stabilities of the biocatalyst was evaluated. After the optimization of immobilization process, the physical and chemical characterization of immobilized lipase was performed. Obtained data showed that the immobilized enzyme seemed better and offered some advantages in comparison with free enzyme. It can be observed that the free lipase loses its initial activity within around 80 min at 60 °C, while the immobilized lipases retain their initial activities of about 56% by HMDI and 82% by GA after 120 min of heat treatment at 60 °C.Results showed that the specific activity of the immobilized lipase with glutaraldehyde was 62.75 U/mg protein, which is 28.13 times higher than that of the immobilized lipase with HMDI. 相似文献
85.
Summary: Biofilms are communities of microorganisms that live attached to surfaces. Biofilm formation has received much attention in the last decade, as it has become clear that virtually all types of bacteria can form biofilms and that this may be the preferred mode of bacterial existence in nature. Our current understanding of biofilm formation is based on numerous studies of myriad bacterial species. Here, we review a portion of this large body of work including the environmental signals and signaling pathways that regulate biofilm formation, the components of the biofilm matrix, and the mechanisms and regulation of biofilm dispersal. 相似文献
86.
Changes in peroxidase activities and soluble proteins in strawberry varieties under salt-stress 总被引:3,自引:0,他引:3
Effects of salt stress on the activity of peroxidase (PRX) isozyme and leaf proteins were studied in the three strawberry
varieties, Camarosa, Tioga and Chandler. Plants were watered with modified 1/3 Hoagland nutrient solution containing 0 (control),
8.5, 17.0 and 34.0 mM NaCl for 30 days fallowing 20 days acclimation. PRX activity was assayed in leaf extracts and PRX profiles
of control and salt treated plants were performed by native polyacrylamide gel electrophoresis (PAGE). During the salt stress
Tioga and Camarosa tolerated the cellular damage with less electrolyte leakage while Chandler exhibited a severe cellular
damage with the highest (87.5 % in 34.0 mM NaCl treatment) electrolyte leakage. Total soluble protein content was decreased
by salinity in Tioga (from 11.35 to 5.86 mg g−1 DW) and Chandler (from 9.35 to 3.90 mg g−1 DW) while it was almost unchanged in Camarosa. Salt stress increased total and specific PRX activity as compared with the
control in all the varieties. In native PAGE, one basic isoperoxidase band (Rf=0.27) was observed commonly with different
band intensity in all the treatments. Therefore, it might be associated with lignification and recovery of cell membrane damage
in strawberry plants under salt stress. 相似文献
87.
Imreh MP Gertow K Cedervall J Unger C Holmberg K Szöke K Csöregh L Fried G Dilber S Blennow E Ahrlund-Richter L 《Journal of cellular biochemistry》2006,99(2):508-516
Previous studies in several laboratories have demonstrated inadvertent chromosomal abnormalities in long-term cultured human embryonic stem cells (HESC). Here, using a two-step selection process we report a functional adaptation of a HESC line, HS181, towards a decreased dependence of extra cellular matrix (ECM) for in vitro survival, that is for growth directly onto a plastic surface. Successful adaptation was paralleled with a karyotype change in 100% of the cells to 47,XX,del(7)(q11.2),+i(12)(p10). The resulting adapted population showed increased survival and growth on plastic and also maintained expression of HESC markers, but showed a decreased pluripotency, as demonstrated by results from embryoid body (EB) formation in vitro. The finding of reduced pluripotency may not be totally unexpected since the variant cells were selected for self-renewal and proliferation, not differentiation during the adaptation to growth on plastic. In the light of recent models of a germ cell origin of HESC it is of particular interest that similar to many of the reported spontaneous HESC mutants, one of the identified specific chromosome abnormalities, i(12p), has also been strongly implicated for human germ cell cancer. However, the mutated HESC variant carrying this mutation failed to grow as a xeno-graft in a mouse model in vivo. This is surprising and needs a further mechanistic analysis for its explanation. Increased knowledge of genetic integrity of HESC may have significance on the understanding of mechanisms for tumor progression and thus strategy for treatments, particularly for tumors occurring in early life. 相似文献
88.
Margit Schraders Laura Ruiz-Palmero Ersan Kalay Jaap Oostrik Francisco?J. del?Castillo Orhan Sezgin Andy?J. Beynon Tim?M. Strom Ronald?J.E. Pennings Celia?Zazo Seco Anne?M.M. Oonk Henricus?P.M. Kunst María Domínguez-Ruiz Ana?M. García-Arumi Miguel del?Campo Manuela Villamar Lies?H. Hoefsloot Felipe Moreno Ronald?J.C. Admiraal Ignacio del?Castillo Hannie Kremer 《American journal of human genetics》2012,91(5):883-889
Already 40 genes have been identified for autosomal-recessive nonsyndromic hearing impairment (arNSHI); however, many more genes are still to be identified. In a Dutch family segregating arNSHI, homozygosity mapping revealed a 2.4 Mb homozygous region on chromosome 11 in p15.1-15.2, which partially overlapped with the previously described DFNB18 locus. However, no putative pathogenic variants were found in USH1C, the gene mutated in DFNB18 hearing impairment. The homozygous region contained 12 additional annotated genes including OTOG, the gene encoding otogelin, a component of the tectorial membrane. It is thought that otogelin contributes to the stability and strength of this membrane through interaction or stabilization of its constituent fibers. The murine orthologous gene was already known to cause hearing loss when defective. Analysis of OTOG in the Dutch family revealed a homozygous 1 bp deletion, c.5508delC, which leads to a shift in the reading frame and a premature stop codon, p.Ala1838ProfsX31. Further screening of 60 unrelated probands from Spanish arNSHI families detected compound heterozygous OTOG mutations in one family, c.6347C>T (p.Pro2116Leu) and c. 6559C>T (p.Arg2187X). The missense mutation p.Pro2116Leu affects a highly conserved residue in the fourth von Willebrand factor type D domain of otogelin. The subjects with OTOG mutations have a moderate hearing impairment, which can be associated with vestibular dysfunction. The flat to shallow “U” or slightly downsloping shaped audiograms closely resembled audiograms of individuals with recessive mutations in the gene encoding α-tectorin, another component of the tectorial membrane. This distinctive phenotype may represent a clue to orientate the molecular diagnosis. 相似文献
89.
Sher L. Hendrickson James A. Lautenberger Leslie Wei Chinn Michael Malasky Efe Sezgin Lawrence A. Kingsley James J. Goedert Gregory D. Kirk Edward D. Gomperts Susan P. Buchbinder Jennifer L. Troyer Stephen J. O'Brien 《PloS one》2010,5(9)
Background
The human mitochondrial genome includes only 13 coding genes while nuclear-encoded genes account for 99% of proteins responsible for mitochondrial morphology, redox regulation, and energetics. Mitochondrial pathogenesis occurs in HIV patients and genetically, mitochondrial DNA haplogroups with presumed functional differences have been associated with differential AIDS progression.Methodology/Principal Findings
Here we explore whether single nucleotide polymorphisms (SNPs) within 904 of the estimated 1,500 genes that specify nuclear-encoded mitochondrial proteins (NEMPs) influence AIDS progression among HIV-1 infected patients. We examined NEMPs for association with the rate of AIDS progression using genotypes generated by an Affymetrix 6.0 genotyping array of 1,455 European American patients from five US AIDS cohorts. Successfully genotyped SNPs gave 50% or better haplotype coverage for 679 of known NEMP genes. With a Bonferroni adjustment for the number of genes and tests examined, multiple SNPs within two NEMP genes showed significant association with AIDS progression: acyl-CoA synthetase medium-chain family member 4 (ACSM4) on chromosome 12 and peroxisomal D3,D2-enoyl-CoA isomerase (PECI) on chromosome 6.Conclusions
Our previous studies on mitochondrial DNA showed that European haplogroups with presumed functional differences were associated with AIDS progression and HAART mediated adverse events. The modest influences of nuclear-encoded mitochondrial genes found in the current study add support to the idea that mitochondrial function plays a role in AIDS pathogenesis. 相似文献90.
Saruhan Guler N. Ozturk K. Sezgin A. Altuntas C. Kadioglu A. Terzi R. 《Russian Journal of Plant Physiology》2021,68(6):1152-1160
Russian Journal of Plant Physiology - Alpha lipoic acid (ALA) is a potent antioxidant molecule that has positive effects on plant growth and the adaptation of plants to environmental stresses.... 相似文献