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排序方式: 共有271条查询结果,搜索用时 32 毫秒
81.
Yildirim K Senel K Karatay S Sisecioglu M Kiziltunc A Ugur M Akcay F 《Cell biochemistry and function》2005,23(4):285-289
We conducted this study to assess serum soluble E-selectin (sE-selectin) levels and erythrocyte membrane Na(+)K(+) ATPase activity in patients with rheumatoid arthritis (RA) and correlate the levels with disease activity. Levels of sE-selectin were measured in the serum of 20 patients with RA and 20 control subjects by an enzyme-linked immunosorbant assay. Na(+)K(+) ATPase activity was determined by a colorimetric method in RA patients and healthy controls. There were no statistically significant differences between the two groups with respect to demographic data such as age and sex (p > 0.05). The serum levels of sE-selectin, ESR and C-reactive protein (CRP) in RA patients were significantly higher than in healthy controls (p < 0.001). Erythrocyte membrane Na(+)K(+) ATPase activity was significantly lower in the RA group than in the control group (p < 0.001). Correlation analysis revealed significant positive correlations between soluble E-selectin and ESR (r = 0.457; p < 0.05) and CRP (r = 0.682; p < 0.01) levels. There were statistically significant negative correlations between erythrocyte membrane Na(+)K(+) ATPase activity and ESR (r = -0.450; p < 0.05) and CRP (r = -0.446; p < 0.05) levels. Additionally, a significant negative correlations between sE-selectin and Na(+)K(+) ATPase activity was observed (r = -0.80; p < 0.001). These results show that decreases in erythrocyte membrane Na(+)K(+) ATPase activity and increases in sE-selectin are observed in RA, and that increased levels of sE-selectin may also reflect disease status or activity. 相似文献
82.
Skacel N Menon LG Mishra PJ Peters R Banerjee D Bertino JR Abali EE 《The Journal of biological chemistry》2005,280(24):22721-22731
Human dihydrofolate reductase (DHFR) protein levels rapidly increase upon exposure to methotrexate, a potent inhibitor of this enzyme. A model to explain this increase proposes that DHFR inhibits its own translation by binding to its cognate mRNA and that methotrexate disrupts the DHFR protein-mRNA complex allowing its translation to resume. In the present study, Chinese hamster ovary cells lacking DHFR were transfected with wild type and mutants of human DHFR to identify amino acids that are essential for increases in DHFR in response to methotrexate. Glu-30, Leu-22, and Ser-118 were involved in the up-regulation of DHFR protein levels by methotrexate and certain other antifolates. Cells transfected with E30A, L22R, and S118A mutants that did not respond to methotrexate up-regulation had higher basal levels of DHFR, consistent with the model, i.e. lack of feedback regulation of these enzymes. Although cells containing the S118A mutant enzyme had higher levels of DHFR and had catalytic activity similar to that of wild type DHFR, they had the same sensitivity to the cytotoxicity of methotrexate, as were cells with wild type DHFR. This finding provides evidence that the adaptive up-regulation of DHFR by methotrexate contributes to the decreased sensitivity to this drug. Based on these observations, a new model is proposed whereby DHFR exists in two conformations, one bound to DHFR mRNA and the other bound to NADPH. The mutants that are not up-regulated by methotrexate are unable to bind their cognate mRNA. 相似文献
83.
Ayhan S. Demir Haluk Hamamci Fatos Doganel Emine Ozgul 《Journal of Molecular Catalysis .B, Enzymatic》2000,9(4-6):157-161
The synthesis of (1S,2R)-1-amino-2-indanol, a key component of HIV protease inhibitor is accomplished in four steps starting from indanone efficiently and with high levels of diastereo- and enantioselectivity. The starting material is converted into 2-acetoxy-1-indanone involving Manganese (III) acetate oxidation . The 2-acetoxyketone is hydrolyzed to 2-hydroxy-1-indanone enantioselectively using Rhizopus oryzae. Selective reduction of 2-hydroxyoxime derivative, derived from the 2-hydroxyketone, gives the amino alcohol up to 98% diastereo- and enantioselectivity. 相似文献
84.
Ercan Varol Selahattin Akcay I. Hakki Ersoy Mehmet Ozaydin Banu Kale Koroglu Simge Varol 《Biological trace element research》2010,133(2):121-127
Sixty-three patients with endemic fluorosis (36 males/27 females; mean age 33.9 ± 8.6 years) and 45 age-, sex-, and body mass
index-matched healthy controls (30 males/15 females; mean age 32.7 ± 8.8 years) were included in this study. Aortic stiffness
indices, aortic strain (AS), aortic distensibility (AD), and aortic strain index (ASI) were calculated from the aortic diameters
measured by echocardiography and blood pressure obtained by sphygmomanometry. The urine fluoride levels of fluorosis patients
were significantly higher than control subjects as expected (1.9 ± 0.1 mg/l vs. 0.4 ± 0.1 mg/l, respectively; P < 0.001). AS and AD were significantly lower in fluorosis patients than in the controls (for AS 5.3 ± 3.6 vs. 8.0 ± 3.4%;
P < 0.001 and for AD 0.2 ± 0.1 vs. 0.3 ± 0.1 cm2 dyn−1 10−3; P < 0.001, respectively). In contrast, signicantly higher ASI was observed in fluorosis patients than in the controls (3.4 ± 0.6
vs. 3.0 ± 0.4; P < 0.001, respectively). The results of our study demonstrate that elastic properties of ascending aorta are impaired in patients
with endemic fluorosis. 相似文献
85.
Stephan Blüml Emine Sahin Victoria Saferding Eliana Goncalves-Alves Eva Hainzl Birgit Niederreiter Anastasia Hladik Tobias Lohmeyer Julia S. Brunner Michael Bonelli Marije I. Koenders Wim B. van den Berg Giulio Superti-Furga Josef S. Smolen Gernot Schabbauer Kurt Redlich 《Arthritis research & therapy》2015,17(1)
IntroductionAutoreactive T cells are a central element in many systemic autoimmune diseases. The generation of these pathogenic T cells is instructed by antigen-presenting cells (APCs). However, signaling pathways in APCs that drive autoimmune diseases, such as rheumatoid arthritis, are not understood.MethodsWe measured phenotypic maturation, cytokine production and induction of T cell proliferation of APCs derived from wt mice and mice with a myeloid-specific deletion of PTEN (myeloid PTEN-/-) in vitro and in vivo. We induced collagen-induced arthritis (CIA) and K/BxN serum transfer arthritis in wt and myeloid-specific PTEN-/- mice. We measured the cellular composition of lymph nodes by flow cytometry and cytokines in serum and after ex vivo stimulation of T cells.ResultsWe show that myeloid-specific PTEN-/- mice are almost protected from CIA. Myeloid-specific deletion of PTEN leads to a significant reduction of cytokine expression pivotal for the induction of systemic autoimmunity such as interleukin (IL)-23 and IL-6, leading to a significant reduction of a Th17 type of immune response characterized by reduced production of IL-17 and IL-22. In contrast, myeloid-specific PTEN deficiency did not affect K/BxN serum transfer arthritis, which is independent of the adaptive immune system and solely depends on innate effector functions.ConclusionsThese data demonstrate that the presence of PTEN in myeloid cells is required for the development of CIA. Deletion of PTEN in myeloid cells inhibits the development of autoimmune arthritis by preventing the generation of a pathogenic Th17 type of immune response.
Electronic supplementary material
The online version of this article (doi:10.1186/s13075-015-0742-y) contains supplementary material, which is available to authorized users. 相似文献86.
Elcin Ozgur Gorkem Kismali Goknur Guler Aytac Akcay Guzin Ozkurt Tevhide Sel Nesrin Seyhan 《Cell biochemistry and biophysics》2013,67(2):743-751
We aimed to investigate the potential hazardous effects of prenatal and/or postnatal exposure to 1800 MHz GSM-like radiofrequency radiation (RFR) on the blood chemistry and lipid peroxidation levels of infant rabbits. A total of 72 New Zealand female and male white rabbits aged 1-month were used. Thirty-six female and 36 male were divided into four groups which were composed of nine infants: (i) Group 1 were the sham exposure (control), (ii) Group 2 were exposed to RFR, 15 min daily for 7 days in the prenatal period (between 15th and 22nd days of the gestational period) (prenatal exposure group). (iii) Group 3 were exposed to RFR 15 min/day (14 days for male, whereas 7 days for female) after they reached 1-month of age (postnatal exposure group). (iv) Group 4 were exposed to RFR for 15 min daily during 7 days in the prenatal period (between 15th and 22nd days of the gestational period) and 15 min/day (14 days for male, whereas 7 days for female) after they reached 1-month of age (prenatal and postnatal exposure group). Results showed that serum lipid peroxidation level in both female and male rabbits changed due to the RFR exposure. However, different parameters of the blood biochemistry were affected by exposure in male and female infants. Consequently, the whole-body 1800 MHz GSM-like RFR exposure may lead to oxidative stress and changes on some blood chemistry parameters. Studies on RFR exposure during prenatal and postnatal periods will help to establish international standards for the protection of pregnants and newborns from environmental RFR. 相似文献
87.
Göknur Kalkan Nevin Karakus Yalçın Baş Zennure Takçı Pınar Özuğuz Ömer Ateş Serbulent Yigit 《Gene》2013
Objective
Alopecia areata (AA) is hypothesized to be an organ-specific autoimmune disease of hair follicles mediated by T cells. As immunological and genetic factors have been implicated in the pathogenesis of AA, the purpose of the present study was to investigate possible associations between the functional Interleukin (IL)-4 gene intron 3 VNTR polymorphism and AA susceptibility and disease progression in Turkish population.Methods
The study group consisted of 116 unrelated patients with AA and 125 unrelated healthy controls. Genomic DNA was isolated and IL-4 gene 70 bp VNTR polymorphism determined by using polymerase chain reaction (PCR) with specific primers.Results
No association was observed between AA patients and controls according to genotype distribution (p = 0.051). The allele distribution of IL-4 gene intron 3 VNTR polymorphism was statistically different between AA patients and control group (p = 0.026). The frequency of P1 allele in patients was significantly higher than that in the control group. When the P2P2 genotype was compared with P1P2 + P1P1 genotypes, a statistically significant difference was observed between patients and controls (p = 0.036). Intron 3 VNTR polymorphism in the IL-4 gene was found to be associated with AA susceptibility in Turkish population.Conclusion
The results suggest that IL-4 VNTR polymorphism in the intron 3 region may be a risk factor for the development of AA among Turkish population. This is the first to report that intron 3 VNTR polymorphism in the IL-4 gene is associated with AA susceptibility. 相似文献88.
Niemann–Pick disease (NPD) is a lysosomal storage disorder that results from the deficiency of a lysosomal enzyme, acid sphingomyelinase. Niemann–Pick disease type A and B is caused by mutations in the sphingomyelin phosphodiesterase gene (SMPD1) coding for ASM. The aim of this study was to evaluate the spectrum of SMPD1 gene mutations in Turkish NPD patients and to study genotype–phenotype associations. We present a molecular analysis of 10 Turkish NPD type A/B patients. Four of the patients had type A and six had type B NPD. All mutant SMPD1 alleles were identified, including 5 different mutations, 1 of which was novel. These mutations included three missense mutations: c.409T>C (p.L137P), c.1262 A>G (p.H421R) and c.1552T>C (p.L549P), a common frameshift mutation in codon 189, identified in three patients, is caused by the deletion of the 567T, introducing a stop codon 65 amino acids downstream (p.P189fsX65), and a novel frameshift mutation c.1755delC (p.P585PfsX24) which was not reported previously. 相似文献
89.
The present study was conducted to determine the total hypericin contents of Hypericum triquetrifolium Turra. and Hypericum scabrum L. species
which are naturally distributed in the flora of Siirt province, Turkey. Hypericin
contents of Hypericum species grown in different geographical aspects (North,
South, East, and West), and it was measured at different harvest times (full blooming and post blooming period). In the current study, it has been determined that
total hypericin content varies considerably according to aspects, plant developmental stages (ontogenetic variance), and species. According to species x aspect
interaction, the highest total hypericin content was recorded from the west aspect
(3.13 mg/g) in Hypericum triquetrifolium, while, the lowest hypericin content was
also obtained from the west aspect (1.22 mg/g) in Hypericum scabrum. When the
highest total hypericin content was analyzed according to aspect x species x harvest time interaction, the highest total hypericin content was produced from
Hypericum triquetrifolium at the harvest of west aspect with 5.28 mg/g, while
the minimum amount of hypericin was obtained from the same aspect in Hypericum scabrum with 0.50 mg/g. In species x harvest time interaction, the highest
total hypericin content was obtained from the full bloom (3.10 mg/g) harvest in
Hypericum triquetrifolium, while the lowest hypericin was obtained from the full
bloom (1.26 mg/g) harvest in Hypericum scabrum. The data suggest that the average total hypericin content was 2.26 mg/g in Hypericum triquetrifolium and
1.28 mg/g in Hypericum scabrum. 相似文献
90.
Tuna Esin Ersoy Yeliz Emine Bulut Pelin Ozdemir Filiz Buyru Nur 《Molecular biology reports》2020,47(3):1605-1612
Molecular Biology Reports - Breast cancer, which is the most common type of cancer among women, is a heterogenous disease. It results from progressive accumulation of genetic and epigenetic... 相似文献