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Signaling of RANK (receptor activator of nuclear factor kappa B) through its ligand RANKL appears critical in osteolysis associated with aseptic loosening (AL). The purpose of this study was to investigate the role of RANK in a murine osteolysis model developed in RANK knockout (RANK(-/-)) mice. Ultra high molecular weight polyethylene (UHMWPE) debris was introduced into established air pouches on RANK(-/-) mice, followed by implantation of calvaria bone from syngeneic littermates. Wild type C57BL/6 (RANK(+/+)) mice injected with either UHMWPE or saline alone were included in this study. Pouch tissues were collected 14 days after UHMWPE inoculation for molecular and histology analysis. Results showed that UHMWPE stimulation induced strong pouch tissue inflammation in RANK(-/-) mice, as manifested by inflammatory cellular infiltration, pouch tissue proliferation, and increased gene expression of IL-1beta, TNFalpha, and RANKL. However, the UHMWPE-induced inflammation in RANK(-/-) mice was not associated with the osteoclastic bone resorption observed in RANK(+/+) mice. In RANK(+/+) mice subjected to UHMWPE stimulation, a large number of TRAP(+) cells were found on the implanted bone surface, where active osteoclastic bone resorption was observed. No TRAP(+) cells were found in UHMWPE-containing pouch tissues of RANK(-/-) mice. Consistent with the lack of osteoclastic activity shown by TRAP staining, no significant UHMWPE particle-induced bone resorption was found in RANK(-/-) mice. A well preserved bone collagen content (Van Gieson staining) and normal plateau surface contour [microcomputed tomography (microCT)] of implanted bone was observed in RANK(-/-) mice subjected to UHMWPE stimulation. In conclusion, this study provides the evidence that UHMWPE particles induce strong inflammatory responses, but not associated with osteoclastic bone resorption in RANK(-/-) mice. This indicates that RANK signaling is essential for UHMWPE particle-induced osteoclastic bone resorption, but does not participate in UHMWPE particle-induced inflammatory response.  相似文献   
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OBJECTIVE: Gelastic seizures are a frequent and well established manifestation of the epilepsy associated with hypothalamic hamartomas. The scalp EEG recordings very seldom demonstrate clear spike activity and the information about the ictal epilepsy dynamics is limited. In this work, we try to isolate epileptic rhythms in gelastic seizures and study their generators. METHODS: We extracted rhythmic activity from EEG scalp recordings of gelastic seizures using decomposition in independent components (ICA) in three patients, two with hypothalamic hamartomas and one with no hypothalamic lesion. Time analysis of these rhythms and inverse source analysis was done to recover their foci of origin and temporal dynamics. RESULTS: In the two patients with hypothalamic hamartomas consistent ictal delta (2-3 Hz) rhythms were present, with subcortical generators in both and a superficial one in a single patient. The latter pattern was observed in the patient with no hypothalamic hamartoma visible in MRI. The deep generators activated earlier than the superficial ones, suggesting a consistent sub-cortical origin of the rhythmical activity. CONCLUSIONS: Our data is compatible with early and brief epileptic generators in deep sub-cortical regions and more superficial ones activating later. SIGNIFICANCE: Gelastic seizures express rhythms on scalp EEG compatible with epileptic activity originating in sub-cortical generators and secondarily involving cortical ones.  相似文献   
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目的观察和评价外剥、内扎硬化注射术治疗混合痔的近期疗效.方法作者采用外剥、内扎硬化注射术治疗混和痔800例.结果近期治愈788例,治愈率98.5%,好转12例,好转率1.5%.治愈天数10~21天.结论外剥、内扎硬化注射术治疗混合痔简单实用,手术时间短,术后痛苦小,伤面愈合快,并发症少,无后遗症,复发率低,是治疗混合痔的较好方法.  相似文献   
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Background  

Patient falls in hospitals are common and may lead to negative outcomes such as injuries, prolonged hospitalization and legal liability. Consequently, various hospital falls prevention programs have been implemented in the last decades. However, most of the programs had no sustained effects on falls reduction over extended periods of time.  相似文献   
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BMP-2 gene polymorphisms and osteoporosis: the Rotterdam Study.   总被引:7,自引:0,他引:7  
After reported associations of variations in the BMP-2 gene with osteoporosis in small populations, we studied the association of the BMP-2 gene polymorphisms Ser37Ala and Arg190Ser with osteoporosis in 6353 men and women from the Rotterdam Study. We did not observe an association of these variants with BMD, bone loss, hip structural analysis parameters, and fracture risk. INTRODUCTION: Bone morphogenetic protein 2 (BMP-2) plays a role in osteoblast differentiation. BMP-2 gene variation has previously been associated with osteoporosis in various small populations, but current evidence remains inconclusive about the exact association with osteoporosis. Therefore, we studied the association of two polymorphisms located in the BMP-2 gene (Ser37Ala and Arg190Ser) and haplotypes defined by these polymorphisms with BMD, rates of bone loss, parameters of hip structural analysis (HSA), and fractures in the Rotterdam Study, a large prospective cohort study of diseases in the elderly. MATERIALS AND METHODS: Databases were searched for polymorphisms and haplotype blocks in the BMP-2 gene region. Allele frequencies for Ser37Ala and Arg190Ser were determined in 60 blacks and 110 Chinese from Coriell panels. Genotype data on Ser37Ala and Arg190Ser were available for 6353 individuals from the Rotterdam Study population. Haplotype alleles defined by Ser37Ala and Arg190Ser were inferred using PHASE software. Genotype and haplotype analyses for BMD (measured at the lumbar spine and femoral neck), bone loss per year (measured at the femoral neck), and HSA were performed using AN(C)OVA. Fractures were analyzed using a Cox proportional-hazards model and logistic regression. All outcomes were adjusted for age, height, and weight. RESULTS: Allele frequencies were 2.5% for Ala37 and 40.2% for Ser190, whereas haplotype allele frequencies were 57.28% (Ser37Arg190), 40.19% (Ser37Ser190), 2.50% (Ala37Arg190), and 0.02% (Ala37Ser190). For BMD, bone loss, HSA outcomes, and (incident) fractures, no differences could be seen between genotype and haplotype groups. Conclusions: In this large population-based cohort of Dutch whites, we conclude that the BMP-2 Ser37Ala and Arg190Ser polymorphisms or haplotypes thereof are not associated with parameters of osteoporosis.  相似文献   
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从感染病毒乳鼠脑组织提取总RNA,采用RT-PCR和分子克隆技术将扩增到的G2糖蛋白基因插入含CMV启动子的pcDNA3.1/His质粒载体中,通过脂质体介导转染COS-7细胞,用SDS-PAGE、Western-blot及IFIA方法分别测定表达产物的相对分子量及特异性。结果证明获得正向插入的G2-pcDNA3.1/His重组表达质粒,表达产物的相对分子量为56ku,与理论预期大小一致,并且可与汉坦病毒H8205株的腹水抗体起特异反应。表明构建的G2-pcDNA3.1/His重组质粒所表达的蛋白为中国汉坦病毒株特有,能在哺乳动物细胞中表达并具有抗原性,重组质粒可应用于汉坦病毒的DNA疫苗研究。  相似文献   
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