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71.
Purpose: Mouse double-stranded DNA-dependent protein kinase (DNA-PK) activity is heat sensitive. Recovery of heat-inactivated DNA repair activity is a problem after combination therapy with radiation and heat. We investigated the mechanism of recovery of heat-inactivated DNA-PK activity.

Methods: Hybrid cells containing a fragment of human chromosome 8 in scid cells (RD13B2) were used. DNA-PK activity was measured by an in vitro assay. Immunoprecipitation of the nuclear extract was performed with an anti-Ku80 antibody. Proteins co-precipitated with Ku80 were separated by sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis and detected by Western blotting using anti-heat shock protein (HSP)72 and anti-heat shock cognate protein (HSC)73 antibodies. HSC73 was overexpressed with the pcDNA3.1 vector. Short hairpin (sh)RNA was used to downregulate HSC73 and HSP72.

Results: The activity of heat-inactivated DNA-PK recovered to about 50% of control during an additional incubation at 37?°C after heat treatment at 44?°C for 15?min in the presence of cycloheximide (which inhibits de novo protein synthesis). Maximal recovery was observed within 3?h of incubation at 37?°C after heat treatment. Constitutively expressed HSC73, which folds newly synthesized proteins, reached maximal levels 3?h after heat treatment using a co-immunoprecipitation assay with the Ku80 protein. Inhibiting HSC73, but not HSP72, expression with shRNA decreased the recovery of DNA-PK activity after heat treatment.

Conclusions: These results suggest that de novo protein synthesis is unnecessary for recovery of some heat-inactivated DNA-PK. Rather, it might be reactivated by the molecular chaperone activity of HSC73, but not HSP72.  相似文献   

72.
IntroductionCognitive deficits and neuropsychiatric symptoms occur in parkinsonian and cerebellar subtypes of Multiple System Atrophy (MSA-P and MSA-C). These symptoms have been investigated mainly in cross-sectional studies. The present 1-year follow-up study aimed at evaluating the evolution of cognitive and neuropsychiatric profile in patients with MSA-C and MSA-P.MethodsTwenty-nine patients with MSA-P, 21 with MSA-C and 30 healthy subjects (HCs) underwent a neuropsychological battery and questionnaires assessing depression and apathy (T0). After 1 year (T1), patients with MSA-C and MSA-P underwent the same neuropsychological and neuropsychiatric tools employed at T0.ResultsAt T0, MSA-P and MSA-C groups were more depressed and apathetic and performed worse on tests assessing repetition abilities, executive and attentive functions than HCs. MSA-P and MSA-C groups did not differ on cognitive variables and neuropsychiatric scales. At T1, a significant worsening in spatial planning and psychomotor speed in MSA-C group and a significant worsening in memory, spatial planning, repetition abilities and functional autonomy in MSA-P group were found. The prevalence of apathy increased in both subtypes, whereas the prevalence of depression was reduced in MSA-C and relatively consistent in MSA-P.ConclusionsThe finding revealed a wide-ranging worsening of cognitive functions in MSA-P and a significant decline in processing speed in MSA-C. These results underline the relevance of evaluating cognitive and psychiatric features of MSA over the course of the disease in the daily clinical practice.  相似文献   
73.
目的:研究PTPN6对前列腺癌细胞PC3的作用及其作用机制。方法:RT-PCR和Western blot实验检测前列腺癌组织和细胞以及癌旁组织和人前列腺上皮细胞中PTPN6的表达量;CCK-8和EDU染色实验检测PTPN6对前列腺癌细胞PC3增殖的影响;Western blot实验检测耐药相关蛋白P-gp和MRP-1的蛋白表达水平。结果:RT-PCR和Western blot结果显示,PTPN6在前列腺癌组织和细胞中的表达量显著低于癌旁组织和人前列腺上皮细胞中的表达量;过表达PTPN6显著抑制前列腺癌PC3细胞的增殖,并降低PC3细胞的耐药性;进一步的研究结果表明PTPN6可通过抑制SP1,并抑制p38 MAPK通路抑制PC3细胞的增殖和耐药。结论:PTPN6能够抑制前列腺癌细胞PC3的增殖和耐药,提高其化疗敏感性,作用机制是通过调控SP1/p38 MAPK信号通路来实现的,这一结果能够为临床上前列腺癌的诊断和治疗提供分子基础。  相似文献   
74.
To provide policy recommendations for managing Coronavirus 19 (COVID-19) in skilled nursing facilities, a group of certified medical directors from several facilities in New York state with experience managing the disease used e-mail, phone, and video conferencing to develop consensus recommendations. The resulting document provides recommendations on screening, protection of staff, screening of residents, management of Coronavirus 19 positive and presumed positive cases, communication during an outbreak, management of admissions and readmissions, and providing emotional support for staff. These consensus guidelines have been endorsed by the Executive Board of the New York Medical Directors Association and the Board of the Metropolitan Area Geriatrics Society.  相似文献   
75.
目的:探讨老年人桡骨远端C型骨折的手术治疗与非手术治疗的疗效差异,评价两种方法的优缺点。方法回顾性分析2009-12—2011-12收治的老年桡骨远端C型骨折68例,按照治疗方法分为A组(手术组)及B组(非手术组),统计分析两组患者的临床资料。结果 A组33例, B组35例,平均随访21.5个月。两组患者的年龄、骨折类型均无差异(P>0.05);术后影像学指标A组优于B组,骨折愈合时间B组优于A组,治疗成本A组大于B组(P<0.05);Cooney评分早期A组优于B组,1年后两组无差异,两组的并发症无差异(P>0.05)。结论老年人桡骨远端C型骨折手术治疗较非手术治疗可获得更好的复位及早期功能,但远期功能恢复无差异。  相似文献   
76.
The chemical composition, structure and surface characteristics of biomaterials/scaffold can affect the adsorption of proteins, and this in turn influences the subsequent cellular response and tissue regeneration. With magnesium/calcium phosphate cements (MCPC) as model, the effects of magnesium (Mg) on the initial adhesion and osteogenic differentiation of bone marrow stromal cells (BMSCs) as well as the underlying mechanism were investigated. A series of MCPCs with different magnesium phosphate cement (MPC) content (0∼20%) in calcium phosphate cement (CPC) were synthesized. MCPCs with moderate proportion of MPC (5% and 10%, referred to as 5MCPC and 10MCPC) were found to effectively modulate the orientation of the adsorbed fibronectin (Fn) to exhibit enhanced receptor binding affinity, and to up-regulate integrin α5β1 expression of BMSCs, especially for 5MCPC. As a result, the attachment, morphology, focal adhesion formation, actin filaments assembly and osteogenic differentiation of BMSCs on 5MCPC were strongly enhanced. Further in vivo experiments confirmed that 5MCPC induced promoted osteogenesis in comparison to ot her CPC/MCPCs. Our results also suggested that the Mg on the underlying substrates but not the dissolved Mg ions was the main contributor to the above positive effects. Based on these results, it can be inferred that the specific interaction of Fn and integrin α5β1 had predominant effect on the MCPC-induced enhanced cellular response of BMSCs. These results provide a new strategy to regulate BMSCs adhesion and osteogenic differentiation by adjusting the Mg/Ca content and distribution in CPC, guiding the development of osteoinductive scaffolds for bone tissue regeneration.  相似文献   
77.
Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital condition. It responds well to early diagnosis and treatment, but otherwise the prognosis is poor. We present our case series of 12 patients (mean age, 2 ± 2.58 yr; age range, 2 mo–8 yr), emphasizing the diagnostic process and discussing our surgical results. The diagnosis of ALCAPA should be suspected in infants who have dilated cardiomyopathy with electrocardiographic changes that suggest ischemia, and in older children who have isolated mitral regurgitation. When clinical suspicion is high, the results of 2-dimensional echocardiography combined with color-flow Doppler studies in expert hands can establish the diagnosis, thus avoiding angiography in critically ill infants. The treatment of choice in our patients was transfer and reimplantation of the left coronary artery onto the ascending aorta. There were 2 deaths: both were infants in extremis who underwent emergency surgery. An older child with severe ventricular dysfunction was given mechanical ventricular assistance and then heart transplantation. As of this report, all 10 survivors remained well and asymptomatic.  相似文献   
78.
目的对医院制剂通鼻消涕颗粒对慢性鼻窦炎鼻黏膜功能是否有调控作用进行临床研究。方法 收集慢性鼻窦炎不伴鼻息肉患者,采用单盲方法随机将患者分为治疗组(通鼻消涕颗粒组)和对照组(克拉霉素片组)。分别给予口服通鼻消涕颗粒和克拉霉素片治疗4周,并对治疗前、治疗2周后、治疗4周后的患者进行糖精试验、鼻部症状VAS评分与鼻内镜Lund Kennedy评分。并采用t检验统计分析。比较服药前、服药后的评分变化。结果 VAS评分提示:治疗组中,治疗2周后、治疗4周后与治疗前相比差异均有统计学意义(P<0.05),对照组在治疗后的各个阶段与治疗前相比均无明显差异(P>0.05)。Lund Kennedy评分提示:治疗组在治疗2周后与治疗前无明显差异,但在治疗4周后有明显改善(P<0.05),对照组则在治疗后各个阶段无明显变化(P>0.05)。糖精试验提示2组在治疗后2周患者糖精清除时间差异无统计学意义(P>0.05),但治疗组在治疗4周后患者糖精清除时间低于对照组(P<0.05)。结论 通鼻消涕颗粒对慢性鼻窦炎的鼻黏膜形态与传输功能有明显改善作用,可以促进鼻黏膜纤毛功能的恢复,并优于克拉霉素片组,且无毒副作用,值得临床上推广应用。  相似文献   
79.
淋巴管作为循环系统的重要组成部分之一,具有调节机体体液稳态,协助免疫监视和肠道脂质吸收等重要作用。淋巴管新生是机体生理和病理过程中维持脉管系统结构和功能正常的重要手段,淋巴管新生调控对于防治肿瘤、心血管等诸多疾病有着潜在的临床转化意义;淋巴回流功能则与关节炎症等疾病发病机制关系密切。在循环系统中,相较于中医药调控血管相关疾病的发病机制已取得很大进展,近年来对于淋巴管的研究则明显相对滞后。本文从中医药作用于淋巴管新生及回流功能角度对这一领域的研究进展作一综述,以期为临床上中医药治疗相关疾病提供新的思路与方法。  相似文献   
80.
Ovarian carcinoma is one of the most lethal malignancies, but only very few prognostic biomarkers are known. The degradome, comprising proteases, protease non-proteolytic homologues and inhibitors, have been involved in the prognosis of many cancer types, including ovarian carcinoma. The prognostic significance of the whole degradome family has not been specifically studied in high-grade serous ovarian cancer. A targeted DNA microarray known as the CLIP-CHIP microarray was used to identify potential prognostic factors in ten high-grade serous ovarian cancer women who had early recurrence (<1.6 years) or late/no recurrence after first line surgery and chemotherapy. In women with early recurrence, we identified seven upregulated genes (TMPRSS4, MASP1/3, SPC18, PSMB1, IGFBP2, CFI – encoding Complement Factor I – and MMP9) and one down-regulated gene (ADAM-10). Using immunohistochemistry, we evaluated the prognostic effect of these 8 candidate genes in an independent cohort of 112 high-grade serous ovarian cancer women. Outcomes were progression, defined according to CA-125 criteria, and death. Multivariate Cox proportional hazard regression models were done to estimate the associations between each protein and each outcome. High ADAM-10 expression (intensity of 2–3) was associated with a lower risk of progression (adjusted hazard ratio (HR): 0.51; 95% confidence interval (CI): 0.29-0.87). High complement factor I expression (intensity 2–3) was associated with a higher risk of progression (adjusted HR: 2.30, 95% CI: 1.17–4.53) and death (adjusted HR: 3.42; 95% CI: 1.72–6.79). Overall, we identified the prognostic value of two proteases, ADAM-10 and complement factor I, for high-grade serous ovarian cancer which could have clinical significance.  相似文献   
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