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排序方式: 共有147条查询结果,搜索用时 15 毫秒
1.
DISC1 gene polymorphisms and the risk of schizophrenia in an Iranian population: A preliminary study
Alireza Shokouhifar Nasrin Askari Shaghayegh Yazdani Jalil Fallah Mehrabadi 《Journal of cellular biochemistry》2019,120(2):1588-1597
Background: Schizophrenia, schizoaffective disorder, and bipolar illness are common psychological disorders with high heritability and variable phenotypes. The disrupted in schizophrenia 1 ( DISC1) gene, on chromosome 1q42, has an essential role in neurite outgrowth and cell signaling. The purpose of this study was to investigate the association of three single-nucleotide polymorphisms (SNPs; rs6675281, rs2255340, and rs2738864) with schizophrenia disorder. These three SNPs were chosen as they had been used in most of the previous studies. Methods: In a case-control study of Iranian population for the first time 778 blood samples were collected including, 402 schizophrenic patients and 376 healthy controls. Genomic DNA was extracted from peripheral blood using DNA extraction kit (BioFlux Co). The genotypes of rs6675281, rs2255340, and rs2738864 were detected by nested allele-specific multiplex polymersae chain reaction (PCR). Results: Our data revealed that the three SNPs are significantly associated with schizophrenia (rs2255349 C>T: confidence interval (CI), 2.115 to 3.268; P = 0.0000 OR: 2.629; rs2738864 C>T: CI, 1.538 to 2.339; P = 0.0000 OR: 1.897; rs6675281 C>T: CI, 2.788 to 4.662; P = 0.0009241 OR: 3.605). Through applying the expectation-maximization (EM) algorithm, we calculated the haplotype frequency, and finally performed haplotype analysis with Bonferroni correction and data preprocessing methods and the results showed rs66875281 to have the highest association. Discussion: Our findings primarily showed that DISC1 gene polymorphisms contribute to schizophrenia risk and have a significant association with this disorder among Iranian population. The strategy was found to be easy, rapid, specific, and consistent for the co-occurring detection of the DISC1 polymorphisms. We could finally confirm that the polymorphisms are related to schizophrenia studied in Iranian population. 相似文献
2.
Indirect evidence suggests that legumes can adjust rapidly theresistance of their root nodules to O2 diffusion. Here we describeexperiments using O2 specific micro-electrodes and dark fieldmicroscopy to study directly the operation of this diffusionbarrier. The O2 concentration sensed by the electrode decreasedsharply in the region of the inner cortex and was less than1.0 mmol m3 throughout the infected tissue in nodulesof both pea (Pisum sativum) and french bean (Phaseolus vulgaris).In a number of experiments the ambient O2 concentration wasincreased to 40% while the electrode tip was just inside theinner cortex. In 13 out of 21 cases the O2 concentration atthis position either remained low and unchanged or increasedirreversibly to near ambient values. In the remaining casesthe O2 concentration increased after 1 to 2.5 min and then decreasedto its former value. These results are ascribed to an increasein resistance of the barrier in response to increased O2 fluxinto the nodule. It was shown microscopically that air spacesboth at the boundary between the infected zone and the innercortex, and within the infected zone started to disappear 3min after nodules were exposed to high ambient O2 concentrationsand had disappeared completely after 8 min. These spaces werenot changed by exposure of the nodule for 10 min to either N2or air. Key words: Oxygen, root nodules, air spaces 相似文献
3.
Evolution of the 28S ribosomal RNA gene in anurans: regions of variability and their phylogenetic implications 总被引:1,自引:0,他引:1
Fifteen restriction sites were mapped to the 28S ribosomal RNA gene of
individuals representing 54 species of frogs, two species of salamanders, a
caecilian, and a lungfish. Eight of these sites were present in all species
examined, and two were found in all but one species. Alignment of these
conserved restriction sites revealed, among anuran 28S rRNA genes, five
regions of major length variation that correspond to four of 12 previously
identified divergent domains of this gene. One of the divergent domains
(DD8) consists of two regions of length variation separated by a short
segment that is conserved at least throughout tetrapods. Most of the
insertions, deletions, and restriction-site variations identified in the
28S gene will require sequence-level analysis for a detailed reconstruction
of their history. However, an insertion in DD9 that is coextensive with
frogs in the suborder Neobatrachia, a BstEII site that is limited to
representatives of two leptodactylid subfamilies, and a deletion in DD10
that is found only in three ranoid genera are probably synapomorphies.
相似文献
4.
Tumor infiltrating lymphocytes (TIL), especially T-cells, have both prognostic and therapeutic applications. The presence of CD8+ effector T-cells and the ratio of CD8+ cells to FOXP3+ regulatory T-cells have been used as biomarkers of disease prognosis to predict response to various immunotherapies. Blocking the interaction between inhibitory receptors on T-cells and their ligands with therapeutic antibodies including atezolizumab, nivolumab, pembrolizumab and tremelimumab increases the immune response against cancer cells and has shown significant improvement in clinical benefits and survival in several different tumor types. The improved clinical outcome is presumed to be associated with a higher tumor infiltration; therefore, it is thought that more accurate methods for measuring the amount of TIL could assist prognosis and predict treatment response. We have developed and validated quantitative immunohistochemistry (IHC) assays for CD3, CD8 and FOXP3 for immunophenotyping T-lymphocytes in tumor tissue. Various types of formalin fixed, paraffin embedded (FFPE) tumor tissues were immunolabeled with anti-CD3, anti-CD8 and anti-FOXP3 antibodies using an IHC autostainer. The tumor area of stained tissues, including the invasive margin of the tumor, was scored by a pathologist (visual scoring) and by computer-based quantitative image analysis. Two image analysis scores were obtained for the staining of each biomarker: the percent positive cells in the tumor area and positive cells/mm2 tumor area. Comparison of visual vs. image analysis scoring methods using regression analysis showed high correlation and indicated that quantitative image analysis can be used to score the number of positive cells in IHC stained slides. To demonstrate that the IHC assays produce consistent results in normal daily testing, we evaluated the specificity, sensitivity and reproducibility of the IHC assays using both visual and image analysis scoring methods. We found that CD3, CD8 and FOXP3 IHC assays met the fit-for-purpose analytical acceptance validation criteria and that they can be used to support clinical studies. 相似文献
5.
Anu Jose Mattam James M. Clomburg Ramon Gonzalez Syed Shams Yazdani 《Biotechnology letters》2013,35(6):831-842
Glycerol has attracted the attention of scientific and industrial communities due to its generation in bulk quantities as a byproduct of biofuel industries. With the rapid growth of these industries in recent years, glycerol is frequently treated as a very low-value byproduct or even a waste product with a disposal cost associated to it. Glycerol is not only abundant and inexpensive but also can generate more reducing equivalents than glucose or xylose. This unique characteristic of glycerol offers a tremendous opportunity for its biological conversion to valuable products at higher yield. This review focuses on research efforts to utilize glycerol as a carbon source for the production of a variety of fuels and chemicals by both native and metabolically engineered microorganisms. 相似文献
6.
Yaghoub Yazdani Neda Keyhanvar Hamid Reza Kalhor Abbas Rezaei 《Biotechnology letters》2013,35(8):1191-1197
Hepcidin is a peptide hormone that plays an important role in iron metabolism. We have produced a recombinant mouse hepcidin-1 by using baculovirus expression system. Its expression yield was 25 μg/ml when cell culture media were supplemented with a protease inhibitor cocktail. The recombinant mouse hepcidin-1 and synthetic human hepcidin-25 had similar effects on reducing ferroportin expression in J774A cell line and in peritoneal macrophages. However, synthetic human hepcidin-25 was more efficient than recombinant mouse hepcidin-1 in reducing iron concentration in blood circulation (p < 0.01). 相似文献
7.
KB Cullberg T Christiansen SK Paulsen JM Bruun SB Pedersen B Richelsen 《Obesity (Silver Spring, Md.)》2013,21(3):454-460
Background:
Vascular growth is a prerequisite for adipose tissue (AT) development and expansion. Some AT cytokines and hormones have effects on vascular development, like vascular endothelial growth factor (VEGF‐A), angiopoietin (ANG‐1), ANG‐2 and angiopoietin‐like protein‐4 (ANGPTL‐4).Methods:
In this study, the independent and combined effects of diet‐induced weight loss and exercise on AT gene expression and proteins levels of those angiogenic factors were investigated. Seventy‐nine obese males and females were randomized to: 1. Exercise‐only (EXO; 12‐weeks exercise without diet‐restriction), 2. Hypocaloric diet (DIO; 8‐weeks very low energy diet (VLED) + 4‐weeks weight maintenance diet) and 3. Hypocaloric diet and exercise (DEX; 8‐weeks VLED + 4‐weeks weight maintenance diet combined with exercise throughout the 12 weeks). Blood samples and fat biopsies were taken before and after the intervention.Results:
Weight loss was 3.5 kg in the EXO group and 12.3 kg in the DIO and DEX groups. VEGF‐A protein was non‐significantly reduced in the weight loss groups. ANG‐1 protein levels were significantly reduced 22‐25% after all three interventions (P < 0.01). The ANG‐1/ANG‐2 ratio was also decreased in all three groups (P < 0.05) by 27‐38%. ANGPTL‐4 was increased in the EXO group (15%, P < 0.05) and 9% (P < 0.05) in the DIO group. VEGF‐A, ANG‐1, and ANGPTL‐4 were all expressed in human AT, but only ANGPTL‐4 was influenced by the interventions.Conclusions:
Our data show that serum VEGF‐A, ANG‐1, ANG‐2, and ANGPTL‐4 levels are influenced by weight changes, indicating the involvement of these factors in the obese state. Moreover, it was found that weight loss generally was associated with a reduced angiogenic activity in the circulation. 相似文献8.
Zarrati Mitra Raji Lahiji Mahsa Salehi Eisa Yazdani Bahareh Razmpoosh Elham Shokouhi Shoormasti Raheleh Shidfar Farzad 《Probiotics and antimicrobial proteins》2019,11(4):1202-1209
Probiotics and Antimicrobial Proteins - Data on the effects of probiotics on adipokines such as omentin-1, nesfatin-1, and adropin are limited. The aim of this study was to evaluate the effects of... 相似文献
9.
Vascular stents influence the post-procedural hemodynamic environment in ways that may encourage restenosis. Understanding how stents influence flow patterns may lead to more hemodynamically compatible stent designs that alleviate thrombus formation and promote endothelialization. This study employed time-resolved Digital Particle Image Velocimetry (DPIV) to compare the hemodynamic performance of two stents in a compliant vessel. The first stent was a rigid insert, representing an extreme compliance mismatch. The second stent was a commercially available nitinol stent with some flexural characteristics. DPIV showed that compliance mismatch promotes the formation of a ring vortex in the vicinity of the stent. Larger compliance mismatch increased both the size and residence time of the ring vortex, and introduced in-flow stagnation points. These results provide detailed quantitative evidence of the hemodynamic effect of stent mechanical properties. Better understanding of these characteristics will provide valuable information for modifying stent design in order to promote long-term patency. 相似文献
10.