Deficient DNA mismatch repair is associated with favorable prognosis in Thai patients with sporadic colorectal cancer

AIM:To determine the prognostic significance of deficient mismatch repair(d MMR) and BRAF V600 E in Thai sporadic colorectal cancer(CRC) patients.METHODS:We studied a total of 211 out of 405 specimens obtained from newly diagnosed CRC patients between October 1,2006 and December 31,2007 at Siriraj Hospital,Mahidol University.Formalinfixed paraffin-embedded blocks of CRC tissue samples w e re a n a l y ze d fo r d M M R b y d e t e c t i o n o f M M R protein expression loss by immunohistochemistry or microsatellite instability using polymerase chain reaction(PCR)-DHPLC.BRAF V600 E mutational analysis was performed in DNA extracted from the same archival tissues by two-round allele-specific PCR and analyzed by high sensitivity DHPLC.Associations between patient characteristics,MMR and BRAF status with diseasefree survival(DFS) and overall survival(OS) were determined by Kaplan-Meier survival plots and log-rank test together with Cox's proportional hazard regression.RESULTS:d MMR and BRAF V600 E mutations were identified in 31 of 208(14.9%) and 23 of 211(10.9%) tumors,respectively.d MMR was more commonly found in patients with primary colon tumors rather than rectal cancer(20.4% vs 7.6%,P =0.01),but there was no difference in MMR status between the right-sided and left-sided colon tumors(20.8% vs 34.6%,P = 0.24).d MMR was associated with early-stage rather than metastatic disease(17.3% vs 0%,P = 0.015).No clinicopathological features such primary site or tumor differentiation were associated with the BRAF mutation.Six of 31(19.3%) samples with d MMR carried the BRAFmutation,while 17 of 177(9.6%) with proficient MMR(p MMR) harbored the mutation(P = 0.11).Notably,patients with d MMR tumors had significantly superior DFS(HR = 0.30,95%CI:0.15-0.77; P = 0.01) and OS(HR = 0.29,95%CI:0.10-0.84; P = 0.02) compared with patients with p MMR tumors.By contrast,the BRAF V600 E mutation had no prognostic impact on DFS and OS.CONCLUSION:The prevalence of d MMR and BRAF V600 E in Thai sporadic CRC patients was 15% and 11%,respectively.The d MMR phenotype was associated with a favorable outcome.

The prognostic value of C-X-C motif chemokine receptor 4 in patients with sporadic malignant peripheral nerve sheath tumors

Background: Recent studies indicate that C-X-C motif chemokine receptor 4(CXCR4) and its ligand, C-X-C motif chemokine ligand 12(CXCL12), stimulate expression of the cell cycle regulatory protein Cyclin D1 in neurofibromatosis 1-associated malignant peripheral nerve sheath tumor(MPNST) cells and promote their proliferation. In this study, we measured the expression of CXCR4, CXCL12, and Cyclin D1 proteins in sporadic MPNST tissues from Chinese patients and investigated their prognostic values.Methods: CXCR4, CXCL12, and Cyclin D1 protein expression in samples from 58 Chinese patients with sporadic MPNST was assessed with immunohistochemical staining.Their prognostic values were evaluated with Kaplan-Meier analysis and a log-rank test. Multivariate Cox regression analysis was used to identify independent prognostic factors.Results: High expression of CXCR4, CXCL12, and Cyclin D1 was observed in 19(32.8%), 32(55.2%), and 16(27.6%)samples, respectively. CXCR4 expression was positively correlated with CXCL12 expression(r = 0.334, P = 0.010) and Cyclin D1 expression(r = 0.309, P = 0.018). Patients with high CXCR4 expression showed longer overall survival than those with low CXCR4 expression(χ~2 = 4.642, P = 0.031).Conclusion: High CXCR4 expression may define a specific subtype of sporadic MPNST with favorable prognosis.

XPC Lys939Gln polymorphism, smoking and risk of sporadic colorectal cancer among Malaysians

AIM: To investigate the risk association of xeroderma pigmentosum group C (XPC ) Lys939Gln polymorphism alone and in combination with cigarette smoking on colorectal cancer (CRC) predisposition. METHODS: Peripheral blood samples of 510 study subjects (255 CRC patients, 255 controls)were collected. DNA was extracted and genotyping was performed using polymerase chain reaction-restriction fragment length polymorphism. The association between polymorphic genotype and CRC predisposition was determined using the OR and 95%CI. RESULTS: The frequency of the homozygous variant (Gln/Gln) genotype was significantly higher in cases compared with controls (16.0% vs 10.2%, P = 0.049). The Gln/Gln genotype of XPC showed a significantly higher association with the risk of CRC (OR = 1.884; 95%CI: 1.082-3.277; P = 0.025). In the case of allele frequencies, variant allele C was associated with a significantly increased risk of CRC (OR = 1.375; 95%CI: 1.050-1.802; P = 0.020). Moreover, the risk was markedly higher for those who were carriers of the Gln/Gln variant genotype and were also cigarette smokers (OR = 3.409; 95%CI: 1.061-10.949; P = 0.032). CONCLUSION: The XPC Gln/Gln genotype alone and in combination with smoking increases the risk of CRC among Malaysians.

Unusual immunohistochemical“null”pattern of four mismatch repair proteins in gastric cancer:A case report

BACKGROUND Immunohistochemical(IHC)staining for mismatch repair(MMR)proteins is useful for gastric cancer treatment and prognosis.Different IHC staining patterns reflect the complex biological phenomena underlying MMR deficiency.We herein report a rare IHC staining pattern of four MMR-related proteins in gastric cancer.CASE SUMMARY A“null”IHC staining pattern of four MMR-related proteins,including MLH1,PMS2,MSH2,and MSH6,in a 67-year-old male patient with gastric cancer pT3N3aM0 revealed promoter hypermethylation of MLH1.Next-generation sequencing showed that these four genes exhibited changes.One of these was the somatic mutation of the missing copy number in exon 14 of MSH2.Mutation analysis using peripheral blood showed no germline mutations in these four genes.The patient had no history of personal or family tumor history.We classified this case as sporadic.The patient returned to normal after operation,and there were no signs of tumor metastasis and recurrence.After six cycles of adjuvant chemotherapy,the patient was discharged in a stable condition.The patient had a mild reaction to chemotherapy and a good prognosis.At present,16 mo after the operation,the patient's condition is stable.CONCLUSION Abnormal MMR protein expression,helpful for individualized follow-up care,helped identify a sporadic case lacking familial clinical management implications.

口腔种植修复患者血清CTHRC1、CX3CL1水平与预后的相关性研究

目的探究口腔种植修复术患者血清胶原三螺旋重复蛋白-1(CTHRC1)、C-X3-C趋化因子配体1(CX3CL1)水平及其与预后的相关性。方法选择接受口腔种植修复术的患者247例为种植修复组,另择同期健康体检者247例为对照组,采用酶联免疫吸附试验(ELISA)分别测定2组术前1周、术后1周、术后1个月血清CTHRC1、CX3CL1水平。根据患者术后6个月时X线检查结果分为预后不良组(28例)和预后良好组(219例),比较患者术后1个月C反应蛋白(CRP)、白细胞介素6(IL-6)、CTHRC1和CX3CL1。采用多因素Cox回归分析口腔种植修复术患者预后不良的影响因素。结果与对照组相比,种植修复组术前1周时血清CTHRC1、CX3CL1水平无明显变化(P>0.05),术后1周及术后1个月时血清CTHRC1、CX3CL1水平升高(P<0.05)。种植修复组患者术前1周、术后1周、术后1个月血清CTHRC1、CX3CL1水平呈先升高后降低,术后1周时达到最高,分别为(426.85±73.52)μg/L和(142.41±15.26)ng/L。口腔种植修复患者术后1个月CTHRC1与CX3CL1呈正相关(r=0.436,P<0.001)。预后不良组患者CRP、IL-6、CTHRC1和CX3CL1水平高于预后良好组(P<0.05)。多因素Cox回归分析显示,CTHRC1和CX3CL1水平升高是口腔种植修复术患者预后不良的独立危险因素(P<0.05)。结论口腔种植修复术预后不良患者血清CTHRC1和CX3CL1水平升高,两者均为患者预后的独立影响因素。

Reliability Analysis of a Cold Standby Repairable System with Repairman Extra Work

This paper deals with a cold standby repairman who can do extra work in idle time. The repairable system with two identical units and one authors are devoted to studying the unique existence and exponential stability of the system solution. C0-semigroup theory is used to prove the existence of a unique nonnegative time-dependent solution of the system. Then by using the theory of resolvent positive operator, the authors derive that dynamic solution of the system exponentially converges to its steady-state one which is the eigenfunction corresponding to eigenvalue 0 of the system operator. Some reliability indices of the system are discussed with a different method from traditional one. The authors also make a profit analysis to determine the optimal service time outside the system to maximize the system profit.

Effects of UV-B radiation and different light repair conditions on the early development of the tetraspores of Chondrus ocellatus Holm

The effects of exposure to UV-B radiation, 280-315 nm, and dark or dark repair conditions on the early development of Chondrus ocellatus Holm collected from Qingdao coast were studied under the laboratory condition. After being exposed to different doses [0, 36, 72, 108, 144 and 180 J/（m2.d）] of UV-B radiation, one treatment of tetraspores were put back to normal culture condition （PAR）, the other treatment were put into dark condition to repair for 2 h. During the cultivation, the diameter of the tetraspores were recorded every 4 d till the 50th day when vertical branches formed in all treatments. Then at the 50th day, CPDs, phycoerythrin, chlorophyll a and MAAs （Palythine and asterina-330） were measured. The results showed that low doses UV-B radiation could significantly accelerate the growth rate of the rate reduced gradually with UV-B radiation keep on tetraspores of C. ocellatus and the growth increasing. The variation trend of both the phycoerythrin and chlorophyll a concentration reduced significantly （P 〈0.05） once given the UV- B radiation. Under UV-B stress, the CPDs were induced, and the concentrations of CPDs were significant low in dark repair groups. The data of MAAs analyzed by LC/MS in the tetraspores of C. ocellatus suggested that there were two MAAs formed （palythine and asterina-330） after UV-B radiation induced, and low dose of UV-B irradiation could significantly induced the concentration of MAAs. From the growth and development state of the tetraspores, negative effects of UV-B radiation on the dark repair groups were more serious than PAR.

Comparison between direct repair and humana cellular nerve allografting during contralateral C7 transfer to the upper trunk for restoration of shoulder abduction and elbow flexion

Direct coaptation of contralateral C7 to the upper trunk could avoid the interposition of nerve grafts. We have successfully shortened the gap and graft lengths, and even achieved direct coaptation. However, direct repair can only be performed in some selected cases, and partial procedures still require autografts, which are the gold standard for repairing neurologic defects. As symptoms often occur after autografting, human acellular nerve allografts have been used to avoid concomitant symptoms. This study investigated the quality of shoulder abduction and elbow flexion following direct repair and acellular allografting to evaluate issues requiring attention for brachial plexus injury repair. Fifty-one brachial plexus injury patients in the surgical database were eligible for this retrospective study. Patients were divided into two groups according to different surgical methods. Direct repair was performed in 27 patients, while acellular nerve allografts were used to bridge the gap between the contralateral C7 nerve root and upper trunk in 24 patients. The length of the harvested contralateral C7 nerve root was measured intraoperatively. Deltoid and biceps muscle strength, and degrees of shoulder abduction and elbow flexion were examined according to the British Medical Research Council scoring system;meaningful recovery was defined as M3–M5. Lengths of anterior and posterior divisions of the contralateral C7 in the direct repair group were 7.64 ± 0.69 mm and 7.55 ± 0.69 mm, respectively, and in the acellular nerve allografts group were 6.46 ± 0.58 mm and 6.43 ± 0.59 mm, respectively. After a minimum of 4-year follow-up, meaningful recoveries of deltoid and biceps muscles in the direct repair group were 88.89% and 85.19%, respectively, while they were 70.83% and 66.67% in the acellular nerve allografts group. Time to C5/C6 reinnervation was shorter in the direct repair group compared with the acellular nerve allografts group. Direct repair facilitated the restoration of shoulder abduction and elbow flexion. Thus, if direct coaptation is not possible, use of acellular nerve allografts is a suitable option. This study was approved by the Medical Ethical Committee of the First Affiliated Hospital of Sun Yat-sen University, China (Application ID:[2017] 290) on November 14, 2017.

Neuronal effects of SP600125 pretreatment in a rat model of cerebral ischemia/reperfusion injury Inhibited down-regulation of DNA repair protein

BACKGROUND： Recent studies have shown that the selective inhibitor of c-Jun N-terminal kinases （JNKs） signaling pathway, SP600125, exhibits neuronal protective effects in a rat model of brain ischemia/reperfusion. OBJECTIVE： To determine the mechanisms of neuroprotective effects of SP600125 in a rat model of brain ischemia/reperfusion, and determine the role of the JNK signaling pathway in SP600125-induced effects. DESIGN, TIME AND SETTING： A randomized, controlled, animal experiment was performed at the Animal Experiment Center, Medical School of Xi＇an Jiaotong University from June 2007 to September 2008. MATERIALS： SP600125 was provided by Biosource, USA; rabbit anti-phospho-JNK （Thr183/Tyr185） polyclonal antibody from Cell Signaling Technology, USA; rabbit anti-X-ray repair cross-complementing protein 1 （XRCC1） and anti-Ku70 polyclonal antibodies from Santa Cruz Biotechnology, USA; and TUNEL kit from Beijing Huamei Biology, China. METHODS： A total of 108 male, 4-month-old, Sprague Dawley rats were randomly assigned to three groups, with 36 rats per group. The sham operation group and ischemia/reperfusion group （I/R group） were intracerebroventricularly injected with 10 μL 1% DMSO. The SP600125-treated group （pre-SP group） was given 10 μL SP600125 （3 μg/μL）. Thirty minutes later, brain ischemia was induced in the I/R and pre-SP groups using the four-vessel occlusion method. Specifically, whole brain ischemia was induced for 6 minutes, and the clips were released to restore carotid artery blood flow. Rats from each group were observed at 2, 6, 12, 24, 48, and 72 hours, with 6 rats for each time point. The sham operation group was treated with the same surgical exposure procedures, with exception of occlusion of the carotid artery. MAIN OUTCOME MEASURES： Hematoxylin-eosin staining was used to observe neuronal survival in the hippocampal CA1 region, TUNEL was used to detect apoptosis in the hippocampal CA1 region, and immunohistochemistry was used to detect expression of phospho-JNK, XRCC1, and Ku70. RESULTS： Following brain ischemia/reperfusion, neuronal survival significantly decreased, and the number of apoptotic cells significantly increased （P 〈 0.01）. Compared with the I/R group, neuronal survival significantly increased in the pre-SP group, and the number of apoptotic cells significantly decreased （P 〈 0.01）. Expression of phospho-JNK increased, and XRCC1 and Ku70 significantly decreased （P 〈 0.05） following ischemia/reperfusion. Compared with the I/R group, expression of phospho-JNK decreased, and XRCC1 and Ku70 significantly increased in the pre-SP group （P 〈 0.05）. Correlation analysis revealed an inverse correlation between phospho-JNK gray value and XRCC1 and Ku70 gray values in the hippocampal CA1 region （r = -0.983, -0.953, P 〈 0.01）. CONCLUSION： SP600125 treatment decreased apoptosis induced by global brain ischemia/reperfusion in the rat hippocampal CA1 region. Results suggested that the neuroprotective effects were due to inhibited phosphorylation of JNK and reduced down-regulation of XRCC1 and Ku70.

Operator Semi-group of Density Evolution Equation for a Repairable Redundant System with Two Same Components

For a repairable redundant system consisting of two same components with exponential lifetime and general repair time distribution, the probability densities of the system in some state at time t were determined by a group of ordinary and partial differential equations, called density evolution equations. It was proved that the time dependent solution of the density evolution equations uniquely exists and strongly converges to its steady state density solution by a semi group method. In this proof, it is not necessary to suppose that the repair rate function is bounded. The technique of the proof is valuable for many density evolution equations.

改良everStick C&B纤维树脂粘接桥在老年切牙缺失修复中的疗效观察

目的:评价改良everStick C&B纤维树脂粘接桥在老年切牙缺失修复中的临床疗效。方法:纳入年龄65岁以上切牙缺失患者32例。其中上颌切牙缺失13例、下颌切牙缺失19例;缺牙1颗13例、缺牙2颗11例、缺牙3颗5例、缺牙4颗3例;基牙松动24例、基牙无松动8例。对所有患者均采取改良everStick C&B纤维树脂粘接桥修复治疗。分别于修复完成后6、 12、 18个月复查,复查内容包括修复体脱粘接、折断、颜色变化、缺损以及基牙松动、牙周组织炎症等6项指标。修复完成后6个月对患者进行满意度调查,调查内容包括治疗过程是否舒适、美观效果是否满意、修复后发音、咀嚼是否舒适等3项指标。结果:32位老年患者修复完成后6个月,6项指标均为A级。12个月,出现1例修复体缺损B级,2例基牙牙周组织炎症B级,其余均为A级。18个月,出现1例修复体缺损B级,3例基牙牙周组织炎症B级,其余均为A级。2例修复体缺损B级经过树脂充填后均达到A级。5例基牙牙周组织炎症B级经过牙周洁治后5~7 d均达到A级。患者满意度调查3项指标均为A级。结论:改良everStick C&B纤维树脂粘接桥在老年切牙缺失修复中临床疗效良好。

血清CX3CL1、LTB4水平与牙列缺失患者口腔种植修复预后的关系

目的 探讨血清趋化因子C-X3-C基元配体1(CX3CL1)、白三烯B4(LTB4)水平与牙列缺失患者口腔种植修复预后的关系。方法 选择2020年7月至2022年6月在该院接受口腔种植修复的牙列缺失患者233例作为观察组,根据术后6个月种植体预后情况,将观察组分为预后优良组与预后不佳组;另选取同期在该院体检的无牙列缺失、缺损的健康受试者233例作为对照组。检测所有受试者血清CX3CL1、LTB4水平;采用Pearson相关分析牙列缺失患者血清CX3CL1水平与LTB4水平的相关性;采用多因素Logistic回归分析影响口腔种植修复预后不佳的影响因素;绘制受试者工作特征(ROC)曲线分析血清CX3CL1、LTB4水平对口腔种植修复后预后不佳的预测价值。结果 观察组血清CX3CL1、LTB4水平均高于对照组(P<0.05)。Pearson相关性分析结果显示,牙列缺失患者血清CX3CL1水平与LTB4水平呈正相关(r=0.518,P<0.05)。本研究中,预后效果良好192例(预后优良组),其余41例作为预后不佳组;预后不佳组患者血清CX3CL1、LTB4水平显著高于预后优良组(P<0.05)。多因素Logistic回归分析结果显示,吸烟及CX3CL1、LTB4水平升高是牙列缺失患者口腔种植修复预后不佳的独立危险因素(P<0.05);ROC曲线分析结果显示,血清CX3CL1、LTB4单独及二者联合预测口腔种植修复后预后不佳的AUC分别为0.778、0.773、0.945。结论 牙列缺失患者血清CX3CL1、LTB4水平升高与口腔种植修复预后不佳密切相关,临床上可用于口腔种植修复后的预后评估。

Asymptotic Stability of a Series-Parallel Repairable System Consisting of Three-Unit with Multiple Vacations of a Repairman

We study a series-parallel repairable system consisting of three units with multiple vacations of a repairman. We first show that all points on the imaginary axis except zero belong to the resolvent set of the operator and zero is an eigenvalue of the operator, and then we prove that the semigroup generated by the operator is irreducible. By combining these results with our previous result we deduce that the dynamic solution of the system converges strongly to its steady-state solution. Thus we obtain asymptotic stability of the dynamic solution of the system.

胱抑素C、高迁移率族蛋白1和生长分化因子-15水平对糖尿病足溃疡皮瓣修复术后早期感染的预测价值

目的探究胱抑素C(Cys C)、高迁移率族蛋白1(HMGB1)、生长分化因子-15(GDF-15)水平对糖尿病足溃疡(DFU)皮瓣修复术后早期感染的预测价值。方法选择2021年7月至2024年3月在河南中医药大学人民医院治疗的DFU患者155例纳入DFU组,根据皮瓣修复术后1周内手术部位是否发生感染将DFU患者分为非感染组(104例)、感染组(51例),另选取同期糖尿病但未发生足溃疡的患者85例纳入对照组。采用乳胶免疫比浊法检测血清Cys C水平,酶联免疫吸附法检测血清HMGB1、GDF-15水平;利用多因素logistic回归分析影响DFU皮瓣修复术后早期感染的因素;ROC曲线分析血清Cys C、HMGB1、GDF-15水平对DFU皮瓣修复术后早期感染的预测价值。结果与对照组相比,DFU组血清Cys C、HMGB1、GDF-15表达水平显著升高(P<0.05);与非感染组相比,感染组FPG、CRP、Cys C、HMGB1、GDF-15表达水平显著升高(P<0.05);Cys C、HMGB1、GDF-15、FPG和CRP均是影响DFU皮瓣修复术后早期感染的独立危险因素(P<0.05);血清Cys C、HMGB1、GDF-15单独预测皮瓣修复术后早期感染的AUC分别为0.810、0.850、0.828,三者联合预测的AUC为0.930,优于三者单独预测(Z_(Cys C-三者联合)=3.381、Z_(HMGB1-三者联合)=2.588、Z_(GDF-15-三者联合)=2.857,均P<0.05)。结论Cys C、HMGB1、GDF-15在DFU患者血清中表达上调,三者均是影响DFU皮瓣修复术后早期感染的因素,三者联合对DFU皮瓣修复术后早期感染有着较高的预测价值。

新疆维吾尔族女性散发性乳腺癌组织中BRCA1、C-erBb-2的表达分析及其临床意义

背景与目的:维吾尔族有着不同于汉族的遗传背景,目前国内对维吾尔族女性散发性乳腺癌组织中BRCA1、C-erBb-2的研究少有报道。本研究旨在探讨BRCA1、C-erBb-2在新疆维吾尔族女性散发性乳腺癌中的表达特点及其临床意义。方法:应用组织芯片技术及免疫组织化学方法检测190例新疆维吾尔族女性乳腺癌组织中BRCA1、C-erBb-2的表达,以100例汉族女性乳腺癌及30例维吾尔族女性乳腺良性肿瘤患者作为对照,分析二者表达的特点和相关性及其与临床病理参数间的关系。结果:新疆维吾尔族、汉族女性散发性乳腺癌组织和维吾尔族女性良性乳腺疾病组织中BRCA1表达阳性率分别为62.1%、28.9%和86.7%,维、汉两民族女性乳腺癌组间差异有统计学意义(P<0.05);维吾尔族女性与汉族女性散发性乳腺癌组织中C-erBb-2的阳性表达差异无统计学意义(26.0%:22.0%,P>0.05);蛋白表达相关分析显示维、汉两民族女性乳腺癌组织中C-erBb-2的表达和BRCA1的表达呈负相关关系(P<0.05);维吾尔族女性散发性乳腺癌组织中BRCA1阳性表达与肿瘤分期、淋巴结转移情况有关(P<0.05);C-erBb-2在肿瘤大小、肿瘤分期、淋巴结转移情况、PR状况方面其阳性表达之间差异有统计学意义(P<0.05)。结论:新疆地区维、汉女性散发性乳腺癌及维吾尔族女性乳腺良性肿瘤组织中BRCA1和C-erBb-2表达均存在显著差异,且维、汉女性乳腺癌组织中BRCA1的阳性表达显示有种族差异性,临床常规联合监测BRCA1和C-erBb-2,有助于指导患者合理治疗和评价预后。

Balb/c小鼠增龄过程中不同脏器线粒体DNA损伤及损伤修复相关基因的变化

为探讨Balb/c小鼠增龄过程中线粒体DNA损伤及其修复基因表达与衰老之间的关系,采用逆转录-多聚酶链反应(RT-PCR)方法,检测年轻与老年Balb/c小鼠脑、肝脏和脾脏中线粒体自身编码基因细胞色素氧化酶亚单位Ⅰ基因(coⅠ)和细胞色素氧化酶亚单位Ⅲ基因(coⅢ)及8-氧鸟嘌呤糖基化酶基因(ogg1)、DNA聚合酶γ(DNA polymeraseγ)基因、胸腺嘧啶乙二醇DNA糖基化酶基因(nth1)等碱基切除修复基因在mRNA水平的变化.用Western印迹方法检测小鼠脾脏中COⅢ和OGG1的蛋白质水平的变化.结果发现,老年小鼠脾脏中coⅠ和coⅢ的mRNA水平比年轻小鼠显著增加(P<0.05),COⅢ的蛋白质水平亦比年轻小鼠显著升高(P<0.05);老年小鼠脾脏OGG1的mRNA和蛋白质水平上均比年轻小鼠显著增加(P<0.05).老年小鼠肝脏和脾脏DNA聚合酶γ和NTH1的mRNA水平比年轻小鼠显著升高(P<0.05).提示线粒体DNA自身编码的基因及碱基切除修复基因的表达失衡可能是Balb/c小鼠衰老的原因之一.

TNFR1-383A/C基因多态性在散发性帕金森病患者中的分布及临床特点分析

目的探讨TNFR1-383A/C基因多态性在散发性帕金森病(sporadic Parkinson disease,SPD)患者和健康人群中的分布,确定其对SPD患者发病年龄和临床特征的影响。方法应用荧光PCR技术对518例SPD患者和521名健康对照个体进行TNFR1-383A/C基因多态性检测,应用χ2检验、非条件Logistic回归模型分析、Kaplan-Meier和life table方法分析其基因多态性与SPD的相关性,及其对SPD发病年龄及临床特征的影响。结果病例组与对照组TNFR1-383A/C基因型及等位基因频率间无统计学差异。按照年龄分组分析发现,病例组发病年龄≥65岁亚组C等位基因频率显著低于对照组≥65岁亚组(6.74%vs.10.10%,P<0.05),并可减少晚发型帕金森病发病的危险性(OR=0.64,95%CI:0.43～0.97,P<0.05),但并未发现CC基因型在两亚组间存在统计学差异(P>0.05)。携带CC、CA和AA基因型的个体发病年龄中位数分别为54岁、62岁和61岁,各基因型者间发病年龄比较无统计学差异(P=0.16),携带CC基因型的个体并未延迟SPD的发病年龄。携带C和非C等位基因个体发病年龄的中位数均为61岁,携带C等位基因的个体并不能延迟SPD的发病年龄(P=0.86)。结论 TNFR1-383A/C等位基因可减少≥65岁人群发生帕金森病的危险,可能在SPD的发病过程中具有保护作用。TNFR1-383A/C基因多态性对SPD的发病年龄和临床特征没有明确影响。

散发性结直肠癌中hMLH1基因启动子区CpG岛MVPs图谱的绘制与分析

目的 绘制散发性结直肠癌患者hMLH1基因启动子区CpG岛甲基化可变位点（methylation variable posi—tions，MVPs）图谱，分析MVPs图谱与hMLH1蛋白表达的关系，寻找CpG岛中影响蛋白表达的关键CpG位点。方法采用重亚硫酸盐测序方法检测患者hMLH1基因启动子区CpG岛甲基化状态；采用免疫组化方法检测相应蛋白表达水平。结果 CpG岛1（CGI—Ⅰ）甲基化阳性率为20％（6／30）；CpG岛2（CGI—Ⅱ）甲基化阳性率为13．33％（4／30）。hMLH1蛋白表达阳性率为50％（15／30）。经X^2检验，CGI—Ⅰ甲基化与hMLH1蛋白表达缺失存在显著性差异（P〈0．05）、CGI-Ⅱ甲基化与hMLH1蛋白表达缺失无差异（P〉0．05）。结论 CGI—Ⅰ甲基化可能导致hMLH1蛋白不表达，其中1～28CpG位点为导致hMLH1蛋白表达缺失的关键区域。

体外培养脊髓神经元损伤后c-Jun蛋白表达

目的 建立一个模拟脊髓全横断损伤后脊髓组分———原代培养的脊髓神经元损伤的模型。探讨中枢神经损伤后损伤应答基因c jun的表达及变化。 方法 取Wistar大鼠 (孕 14d)脊髓 ,培养 10～ 12d后 ,采用所设计的标准模板 ,直视下进行损伤。观察损伤前、后不同时间神经元的形态及即刻早期基因c jun的表达及变化。 结果 脊髓神经元损伤 10min后胞核即有c Jun标记 ,损伤 2h后最多 ,而且阳性神经元的密度与划痕之间的距离呈明显的反比关系。 结论 受机械损伤的神经元中 ,c Jun表达阳性意味着此即刻早期基因产物已进入细胞核内起着“第三信使”的作用。

西门子Multimobil 5C高频移动式C型臂故障维修

0引言随着医疗新技术的飞速发展,移动医疗设备以其轻便、易操作、成像速度快的优势进入各大医院,并得到广泛的应用。西门子Multimobil 5C高频移动式C型臂,以其结构简单、低剂量、便携的优点在骨科手术中使用广泛。我院于2010年引进2组西门子Multimobil 5C高频移动式C型臂进行骨科手术的术中定位和透视。从使用至今,2组设备运行基本良好,给手术带来了很大的方便。