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71.
目的:探讨人工全髋关节置换治疗成人髋关节发育不良并骨性关节炎的临床疗效。方法:对2009年7月至2012年7月入住我院的60例成人髋关节发育不良并骨性关节炎患者行人工全髋关节置换术治疗。分析治疗优良率、手术前后不同Crowe分型Harris评分、手术前后行走及疼痛情况、手术前后生活质量。结果:1根据Harris评分,本组治疗优良率91.67%(55/60);2术后各Crowe分型患者Harris评分均显著高于术前,差异均具有统计学意义(P<0.05);3本组术前自行行走及辅助行走例数分别为23及37例,术后分别为39例及21例;术前疼痛情况:无、轻、中及重度疼痛例数分别为1例、6例、22例及31例,术后分别为18例、28例、12及2例,手术前后行走情况及疼痛情况差异均具有统计学意义(P<0.05);4根据SF-36生活质量评价标准,术后生活质量评分为(142.16±10.32)分,显著高于术前(115.24±7.34)分,差异具有统计学意义(P<0.05)。结论:人工全髋关节置换治疗成人髋关节发育不良并骨性关节炎的临床疗效显著,术后患者髋关节功能及生活质量明显改善,应在临床上加以推广。 相似文献
72.
The activation of the atypical PKC zeta in light‐induced retinal degeneration and its involvement in L‐DNase II control
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Imene Jaadane Sabine Chahory Chloé Leprêtre Boubaker Omri Laurent Jonet Francine Behar‐Cohen Patricia Crisanti Alicia Torriglia 《Journal of cellular and molecular medicine》2015,19(7):1646-1655
Light‐induced retinal degeneration is characterized by photoreceptor cell death. Many studies showed that photoreceptor demise is caspase‐independent. In our laboratory we showed that leucocyte elastase inhibitor/LEI‐derived DNase II (LEI/L‐DNase II), a caspase‐independent apoptotic pathway, is responsible for photoreceptor death. In this work, we investigated the activation of a pro‐survival kinase, the protein kinase C (PKC) zeta. We show that light exposure induced PKC zeta activation. PKC zeta interacts with LEI/L‐DNase II and controls its DNase activity by impairing its nuclear translocation. These results highlight the role of PKC zeta in retinal physiology and show that this kinase can control caspase‐independent pathways. 相似文献
73.
Selina McHarg Nicole Brace Paul N. Bishop Simon J. Clark 《Journal of visualized experiments : JoVE》2015,(105)
Age-related macular degeneration (AMD) is a leading cause of visual impairment in the developed world. The disease manifests itself by the destruction of the center of the retina, called the macula, resulting in the loss of central vision. Early AMD is characterised by the presence of small, yellowish lesions called soft drusen that can progress onto late AMD such as geographic atrophy (dry AMD) or neovascularisation (wet AMD). Although the clinical changes are well described, and the understanding of genetic influences on conferring AMD risk are getting ever more detailed, one area lacking major progress is an understanding of the biochemical consequences of genetic risk. This is partly due to difficulties in understanding the biochemistry of Bruch’s membrane, a very thin extracellular matrix that acts as a biological filter of material from the blood supply and a scaffold on which the retinal pigment epithelial (RPE) cell monolayer resides. Drusen form within Bruch’s membrane and their presence disrupts nutrient flow to the RPE cells. Only by investigating the protein composition of Bruch’s membrane, and indeed how other proteins interact with it, can researchers hope to unravel the biochemical mechanisms underpinning drusen formation, development of AMD and subsequent vision loss. This paper details methodologies for enriching either whole Bruch’s membrane, or just from the macula region, so that it can be used for downstream biochemical analysis, and provide examples of how this is already changing the understanding of Bruch’s membrane biochemistry. 相似文献
74.
Vera Muders Silke Kerruth Víctor A. Lórenz-Fonfría Christian Bamann Joachim Heberle Ramona Schlesinger 《FEBS letters》2014
Channelrhodopsin-1 from Chlamydomonas augustae (CaChR1) is a light-activated cation channel, which is a promising optogenetic tool. We show by resonance Raman spectroscopy and retinal extraction followed by high pressure liquid chromatography (HPLC) that the isomeric ratio of all-trans to 13-cis of solubilized channelrhodopsin-1 is with 70:30 identical to channelrhodopsin-2 from Chlamydomonas reinhardtii (CrChR2). Critical frequency shifts in the retinal vibrations are identified in the Raman spectrum upon transition to the open (conductive P2380) state. Fourier transform infrared spectroscopy (FTIR) spectra indicate different structures of the open states in the two channelrhodopsins as reflected by the amide I bands and the protonation pattern of acidic amino acids. 相似文献
75.
PurposeIt has been suggested that nitric oxide (NO) has a role in ischemic retinopathies. Since retinal ischemia may develop in retinal vein occlusion, we investigated the presence of nitric oxide in the pathogenesis of central retinal vein occlusion (CRVO).MethodsEighteen consecutive patients with CRVO were included in this study. Aqueous humor specimens were obtained within 21 days of diagnosis. Samples of aqueous humor were also collected from 20 control patients undergoing cataract surgery. For each sample after reduction of nitrate to nitrite with vanadium chloride (VCl3), we used spectrophotometric method for simultaneous detection of nitrate and nitrite (NOx).ResultsMean level of aqueous humor NOx in CRVO and control group was 94.1 ± 23.2 μmol/l and 55.6 ± 11.0 μmol/l, respectively. The difference between two groups was statistically significant (p < 0.0001).ConclusionsOur results may support involvement of nitric oxide in the pathogenesis of CRVO. 相似文献
76.
The retina is one of the most essential elements of vision pathway in vertebrate. The dysplasia of retina cause congenital blindness or vision disability in individuals, and the misbalance in adult retinal vascular homeostasis leads to neovaseularization-associated diseases in adults, such as diabetic retinopathy or age-related macular degeneration. Many developmental signaling pathways are involved in the process of retinal development and vascular homeostasis. Among them, Notch signaling pathway has long been studied, and Notch signaling-interfered mouse models show both neural retina dysplasia and vascular abnormality. In this review, we discuss the roles of Notch signaling in the maintenance of retinal progenitor cells, specification of retinal neurons and glial cells, and the sustaining of retina vascular homeostasis, especially from the aspects of conditional knockout mouse models. The potential of Notch signal mampulation may provide a powerful cell fate- and neovascularization-controlling tool that could have important applications in la'eatment of retinal diseases. 相似文献
77.
David E. Kling Amanda J. Cavicchio Christina A. Sollinger Jay J. Schnitzer T. Bernard Kinane David S. Newburg 《Birth defects research. Part B, Developmental and reproductive toxicology》2010,89(3):223-232
BACKGROUND: Nitrofen is a diphenyl ether that induces congenital diaphragmatic hernia (CDH) in rodents. Its mechanism of action has been hypothesized as inhibition of the retinaldehyde dehydrogenase (RALDH) enzymes with consequent reduced retinoic acid signaling. METHODS: To determine if nitrofen inhibits RALDH enzymes, a reporter gene construct containing a retinoic acid response‐element (RARE) was transfected into HEK‐293 cells and treated with varying concentrations of nitrofen in the presence of retinaldehyde (retinal). Cell death was characterized by caspace‐cleavage microplate assays and terminal deoxynucleotidyl transferase dUTP nick end‐labeling (TUNEL) assays. Ex vivo analyses of cell viability were characterized in fetal rat lung explants using Live/Dead staining. Cell proliferation and apoptosis were assessed using fluorescent immunohistochemistry with phosphorylated histone and activated caspase antibodies on explant tissues. Nile red staining was used to identify intracellular lipid droplets. RESULTS: Nitrofen‐induced dose‐dependent declines in RARE‐reporter gene expression. However, similar reductions were observed in control‐reporter constructs suggesting that nitrofen compromised cell viability. These observed declines in cell viability resulted from increased cell death and were confirmed using two independent assays. Ex vivo analyses showed that mesenchymal cells were particularly susceptible to nitrofen‐induced apoptosis while epithelial cell proliferation was dramatically reduced in fetal rat lung explants. Nitrofen treatment of these explants also showed profound lipid redistribution, primarily to phagocytes. CONCLUSIONS: The observed declines in nitrofen‐associated retinoic acid signaling appear to be independent of RALDH inhibition and likely result from nitrofen induced cell death/apoptosis. These results support a cellular apoptotic mechanism of CDH development, independent of RALDH inhibition. Birth Defects Res (Part B) 89:223–232, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
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79.
Oxidative damage contributes to retinal cell death in patients with age-related macular degeneration or retinitis pigmentosa. One approach to treatment is to identify and eliminate the sources of oxidative damage. Another approach is to identify treatments that protect cells from multiple sources of oxidative damage. In this study, we investigated the effect of increased expression of glial cell line-derived neurotrophic factor (GDNF) in three models of oxidative damage-induced retinal degeneration. Double transgenic mice with doxycycline-inducible expression of GDNF in the retina were exposed to paraquat, FeSO(4), or hyperoxia, all sources of oxidative damage and retinal cell death. Compared to controls, mice with increased expression of GDNF in the retina showed significant preservation of retinal function measured by electroretinograms, reduced thinning of retinal cell layers, and fewer TUNEL-positive cells indicating less retinal cell death. Mice over-expressing GDNF also showed less staining for acrolein, nitrotyrosine, and 8-hydroxydeoxyguanosine, indicating less oxidative damage to lipids, proteins, and DNA. This suggests that GDNF did not act solely to allow cells to tolerate higher levels of oxidative damage before initiation of apoptosis, but also reduced damage from oxidative stress to critical macromolecules. These data suggest that gene transfer of Gdnf should be considered as a component of therapy for retinal degenerations in which oxidative damage plays a role. 相似文献
80.