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951.
Objective: The present study was designed to investigate the association of angiotensin-converting enzyme (ACE) rs4343 and rs4362 polymorphisms with the susceptibility to osteoarthritis (OA). Methods: 109 knee OA patients and 114 healthy people were enrolled in the study. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to perform the genotyping for two groups and the linkage disequilibrium and haplotype were analyzed using Haploview software. The differences of genotype and allele frequencies were analyzed by χ2 test and Fisher’s exact test. The relationship between ACE polymorphisms and OA susceptibility was represented by odds ratios (ORs) with 95% confidence intervals (95% CIs). Results: The genotypes distributions of ACE rs4343 and rs4362 polymorphisms in control groups were accordance with HWE. ACE rs4343 polymorphism was associated with the significantly increased risk of OA (AG vs. AA: OR=2.41, P=0.003; GG vs. AA: OR=5.35, P=0.015; G vs. A: OR=2.27, P<0.001). Similarly, rs4362 polymorphisms was also a risk factor for OA (CT vs. CC: OR=2.60, P=0.005; TT vs. CC: OR=3.15, P=0.003; T vs. C: OR=1.88, P=0.001). The result of haplotype analysis showed complete linkage disequilibrium in rs 4343 and rs 4362 polymorphisms. The G-T haplotype significantly increased OA susceptibility, but A-C is a protective factor for the occurrence of OA. Conclusion: Significant correlation exists between ACE rs4343 and rs4362 polymorphisms and OA. In haplotype analysis, A-C haplotype may provide protection against OA, and G-T haplotype may be a risk factor for the development of OA.  相似文献   
952.
Polygonatum sibiricum polysaccharide (PSP) is a traditional Chinese medicine and is widely used to treat many diseases for hundreds of years conventionally. This study was to access the effects of PSP on the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) in the mice. Cells collected from BALB/C mice in the bone marrow were isolated and cultured with osteogenic medium (OM) with different concentrations of PSP. The proliferation and morphological changes of BMSCs were observed using an inverted microscope. Flow cytometric analysis was used to identify the BMSCs. MTT test was performed to analyze the proliferation and viability of the cells. ELISA was used to determine the expression levels of alkaline phosphatase (ALP), osteocalcin (OC), N-terminal propeptide of type I procollagen (PINP) and bone morphogenetic protein-2 (BMP-2). Immunocytochemistry and western blot were respectively used to determine the expressions of bone sialoprotein (BSP) and SPARC/osteonectin (OSN). The growth curves of the proliferation and differentiation of the Control, OM, 17β-E2 and PSP groups were increased. Compared to the Control and OM groups, the expression levels of ALP, OC, PINP and BMP-2 were significantly increased in the PSP induced group (P<0.05). Immunocytochemistry and western blot showed that BSP and SPARC were increased after induction of PSP compared to the OM group (P<0.05). The study demonstrates that PSP promotes the proliferation and enhances the viability of BMSCs during osteogenic differentiation. Therefore, PSP may be a potential treatment of osteoporosis in the clinic.  相似文献   
953.
Objectives: Periodontal ligament stem cells (PDLSCs) are characterized by having multipotential differentiation and immunoregulatory properties, which are the main mechanisms of PDLSCs-mediated periodontal regeneration. Periodontal or bone regeneration requires coordination of osteoblast and osteoclast, however, very little is known about the interactions between PDLSCs and osteoblast-like cells or osteoclast precursors. In this study, the indirect co-culture approach was introduced to preliminarily elucidate the effects of PDLSCs on differentiation of osteoblast-like cells and osteoclast precursors in vitro. Materials and methods: Human PDLSCs were obtained from premolars extracted and their stemness was identified in terms of their colony-forming ability, proliferative capacity, cell surface epitopes and multi-lineage differentiation potentials. A noncontact co-culture system of PDLSCs and preosteoblastic cell line MC3T3-E1 or osteoclast precursor cell line RAW264.7 was established, and osteoblastic differentiation of MC3T3-E1 and osteoclastic differentiation of RAW264.7 were evaluated. Results: PDLSCs exhibited features of mesenchymal stem cells. Further investigation through indirect co-culture system showed that PDLSCs enhanced ALP activity, expressions of ALP, Runx2, BSP, OPN mRNA and BSP, OPN proteins and mineralization matrix deposition in MC3T3-E1. Meanwhile, they improved maturation of osteoclasts and expressions of TRAP, CSTK, TRAF6 mRNA and TRAP, TRAF6 proteins in RAW264.7. Conclusions: PDLSCs stimulates osteoblastic differentiation of osteoblast precursors and osteoclastic differentiation of osteoclast precursors, at least partially, in a paracrine fasion.  相似文献   
954.
In southern China, glucose-6-phosphate dehydrogenase (G6PD) deficiency is a significant health problem, and the incidence ranged from 0.5 to 4.08% in different Chinese population. The aims of this study are to investigate the molecular epidemiological characteristic of the G6PD gene among Chinese Hakka in southern Jiangxi province. 2331 unrelated subjects were screened for G6PD deficiency by a fluorescent test. DNA from deficient individuals was analyzed by a gene chip analysis for thirteen common Chinese G6PD mutations. In total, 3.60% (82/2331; 95% CI 2.77-4.27) of the sample were found to be G6PD-deficient. Eight mutations were found from 80 samples. However, mutation(s) for the two remaining samples were unknown. The most common mutations were G6PD Canton (1376 G>T) and G6PD Kaiping (1388 G>A), and the following mutations were 1311 polymorphism (1311 C>T), G6PD Gaohe (95 A>G), G6PD Chinese-5 (1024 C>T), G6PD Maewo (1360 C>T), Shunde (592 C>T), G6PD Viangchan (871 G>A) and Chinese-3 (493 A>G). This is the first report of G6PD deficiency among Chinese Hakka population in Jiangxi province.  相似文献   
955.
956.
957.
目的:应用引进的德国仪器及新技术探讨并建立健康成人错误相关负电位(ERN)的正常值。方法:应用德国Brain Products公司的ERP记录与分析系统,对50例21~55岁健康成人右利手受试者,作了ERN检测。结果:(1)32个头皮记录点皆在约100~150ms处出现了一个负波,健康成人ERN波形较稳定。(2)在Cz、Fz、Pz、C3、C4 5个脑区,建立了健康成人ERN潜伏期和波幅均值。(3)左右侧比较及男女性别比较差异无统计学意义(P>0.05)。结论:健康成人ERN较稳定和可靠。ERN可作为一个有临床推广应用价值的ERP而用于神经精神科临床。  相似文献   
958.
目的分析2008—2012年成人浮膝损伤患者的临床特点,探讨青年患者与中老年患者性别、合并骨折及骨折类型构成的差异,为此类骨折的诊治、预防等临床研究提供参考。方法回顾性分析河北医科大学第三医院2008年1月—2012年12月间诊治的成人(≥16岁)浮膝损伤患者资料,排除陈旧骨折、病理骨折及假体周围骨折等。所有影像资料由经过培训的4名本院骨科住院医师进行整理分型,并由本院2名骨科主任医师及1名放射科主任医师进行监督检验,统计年龄、性别、骨折类型及合并骨折等数据。≤45岁患者为青年组,>45岁患者为中老年组。结果5年间共诊治成人浮膝损伤204例208侧,占成人全身骨折的0.40%(204/52225),占成人股骨骨折的3.93%(204/5196),占成人胫腓骨骨折2.49%(204/8199)。其中男173例,女31例;年龄16~85岁;青年组153例,中老年组51例。青年患者和中老年患者中均以男性为主,分别占90.20%(138/153)和68.63%(35/51),差异有统计学意义(字2=13.808,P<0.01)。浮膝损伤患者中131例合并其他部位骨折,占浮膝损伤患者的64.22%(131/204),主要为合并足部骨折37例,尺桡骨骨折33例,骨盆-髋臼骨折31例,股骨近端骨折25例,对侧股骨骨折25例等;其中青年组合并其他部位骨折95例,中老年组36例,差异无统计学意义(字2=1.202,P>0.05)。 FraserⅠ型骨折87侧,Ⅱ型骨折121侧,青年组与中老年组患者FraserⅠ型、Ⅱa型、Ⅱb型、Ⅱc型分别是70、40、16、30侧和17、12、5、18侧,两组各型骨折构成比差异并无统计学意义(字2=5.502,P>0.05);Ⅱ型骨折中Ⅱb型骨折最少(21侧),Ⅱa、Ⅱc型骨折所占比例相近,但青年患者Ⅱa型(46.51%,40/86)骨折多于Ⅱc型(34.88%,30/86)骨折,中老年患者中Ⅱc型(51.43%,18/35)骨折较Ⅱa型(34.29%,12/35)骨折更多。结论青年男性为浮膝损伤的高危人群,常合并其他部位骨折。胫骨平台较股骨髁发生骨折的风险高,且骨折风险均随着年龄的增长而增高。  相似文献   
959.
Influenza A virus (IAV) infection is a major worldwide public health problem. However, the factors involved in mediating the inflammatory response to this infection and their relationships remain poorly understood. Here, we show that IAV infection stimulates the expression of the soluble IL-6 receptor (sIL-6R), a multifunctional protein involved in IL-6 signaling. Interestingly, sIL-6R expression upregulated the levels of its own ligand, IL-6 and those of the pro-inflammatory cytokine IL-32. shRNA-mediated knockdown of sIL-6R suppressed IL-6 and IL-32, indicating that this regulation is dependent on sIL-6R during IAV infection. Furthermore, our results demonstrate that IL-32 participates in a negative feedback loop that inhibits sIL-6R while upregulating IL-6 expression during IAV infection. Therefore, we show that sIL-6R is a critical cellular factor involved in the acute inflammatory response to viral infection.  相似文献   
960.
多发性硬化症(MS)是一种可在中枢神经系统引起髓鞘缺失的炎症性疾病,对该病的研究因其标本难以获取而备受限制.建立相应的动物疾病模型是研究MS病理过程、发病机制以及寻找药物靶点的重要途径.MS的动物模型包括自身免疫性脑脊髓炎模型、病毒模型和化学毒性模型.了解这几种MS动物模型的研究进展很有意义.  相似文献   
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