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1.
目的:以EGFR抑制剂为介质,研究EGFR/KRAS通路对人非小细胞肺癌A549和H1299细胞中免疫检查点抑制剂PD-L1表达的影响,探讨靶向治疗与免疫治疗联用在相关肿瘤临床治疗中的潜在价值。方法:Western blotting检测A549和H1299细胞经Erlotinib处理后细胞中c-myc的表达量变化; RT-PCR法检测Erlotinib对A549和H1299细胞中c-myc下游基因分化抗原簇47(cluster of differentiation 47,CD47)及PD-L1转录水平的调控,同时平行检测在c-myc基因沉默后,Erlotinib对CD47及PD-L1转录水平的调控;Western blotting检测Erlotinib用量与PD-L1表达的相关性;通过与肿瘤浸润T细胞(tumor infiltrating T cell,TIL-T)共培养,检测Erlotinib影响前后A549和H1299细胞对TIL-T细胞治疗的敏感度。结果:Erlotinib能显著下调c-myc在A549和H1299细胞内的表达量(P<0.01);c-myc蛋白表达量受Erlotinib影响下调后,PD-L1的转录水平也受到了明显的影响(P<0.01),但Erlotinib对于c-myc沉默的A549和H1299细胞株中CD47及PD-L1的转录水平影响很小(P>0.05);Erlotinib剂量对A549和H1299细胞中PD-L1的表达量呈现出显著的正相关性,但对c-myc沉默的细胞株影响不大(P>0.05),结果与转录水平一致;Erlotinib处理后,A549和H1299细胞对TIL-T细胞的抵抗能力显著降低,细胞凋亡信号caspase-3激活更加明显。结论:Erlotinib能通过EGFR通路调控c-myc在细胞中的表达水平,进而介导PD-L1表达水平降低,增强TIL-T细胞对A549和H1299细胞的杀伤能力。  相似文献   
2.
目的探讨异基因造血干细胞移植患者3年内的生活质量变化轨迹及影响因素。方法采用便利抽样法,选取2016年7月—2017年10月于苏州市某三级甲等医院行异基因造血干细胞移植的患者作为调查对象,在患者移植前(入仓前1~2 d)、移植后1个月、3个月、半年、1年、1年半及3年时采用一般资料调查表及癌症治疗功能评价-骨髓移植测评量表进行调查。结果异基因造血干细胞移植患者的癌症治疗功能评价-骨髓移植测评量表总分在移植后1个月时降至最低,此后呈逐渐上升趋势,半年时基本恢复至移植前水平,3年时总分显著高于移植前,差异具有统计学意义(P<0.05)。生理健康、功能健全及干细胞移植3个维度得分与癌症治疗功能评价-骨髓移植测评量表总分变化轨迹一致,呈波动上升型;情绪稳定维度在移植前得分最低,随移植时间延长逐渐上升;社交/家庭健全维度移植前得分与移植后各时间点得分比较,差异无统计学意义(P>0.05)。多元线性回归分析结果显示,影响患者移植后3年时生活质量的主要因素为居住地(t=3.175,P=0.002)、家庭人均月收入(t=3.320,P=0.001)、移植相关并发症(t=-6.955,P&l...  相似文献   
3.
IF1 (ATPIF1) is a nuclear DNA-encoded mitochondrial protein whose activity is inhibition of the F1Fo-ATP synthase to control ATP production. IF1 activity remains unknown in the regulation of GLP-1 activity. In this study, IF1 was examined in the diet-induced obese mice using the gene knockout (If1-KO) mice. The mice gained more body weight on a high fat diet without a change in food intake. Insulin tolerance was impaired, but the oral glucose tolerance was improved through an increase in GLP-1 secretion. The KO mice exhibited an improved intestine structure, mitochondrial superstructure, enhanced mitophagy, reduced apoptosis and decreased adenine nucleotide translocase 2 (ANT2) protein in the intestinal epithelial cells together with preserved gut microbiota. The data suggest that GLP-1 secretion was enhanced in the obese If1-KO mice to preserve glucose tolerance through a signaling pathway of ANT2/mitochondria/L-cells/GLP-1/insulin. IF1 is a potential mitochondrial target for induction of GLP-1 secretion in L-cells.Key words: GLP-1, ATPIF1, ANT2, L-cells, Mitophagy, Microbiota, Glucose tolerance, Insulin resistance  相似文献   
4.
The posterolateral approach to ankle joint is well suited for ORIF of posterior malleolar fractures. There are no major neurovascular structures endangering this approach other than the sural nerve. The sural nerve is often used as an autologous peripheral nerve graft and provides sensation to the lateral aspect of the foot. The aim of this paper is to measure the precise distance of the sural nerve from surrounding soft tissue structures so as to enable safe placement of skin incision in posterolateral approach. This is a retrospective image review study involving 64 MRI scans. All measurements were made from Axial T1 slices. The key findings of the paper is the safety window for the sural nerve from the lateral border of tendoachilles (TA) is 7 mm, 1.3 cm and 2 cm at 3 cm above ankle joint, at the ankle joint and at the distal tip of fibula respectively. Our study demonstrates the close relationship of the nerve in relation to TA and fibula in terms of exact measurements. The safety margins established in this study should enable the surgeon in preventing endangerment of the sural nerve encountered in this approach.  相似文献   
5.
Early and accurate diagnosis of liver fibrosis is necessary for HBeAg-positive chronic hepatitis B (CHB) patients with normal or slightly increased alanine aminotransferase (ALT), Liver biopsy and many non-invasive predicting markers have several application restrictions in grass-roots hospitals. We aimed to construct a non-invasive model based on routinely serum markers to predict liver fibrosis for this population.A total of 363 CHB patients with HBeAg-positive, ALT ≤2-fold the upper limit of normal and liver biopsy data were randomly divided into training (n = 266) and validation groups (n = 97). Two non-invasive models were established based on multivariable logistic regression analysis in the training group. Model 2 with a lower Akaike information criterion (AIC) was selected as a better predictive model. Receiver operating characteristic (ROC) was used to evaluate the model and was then independently validated in the validation group.The formula of Model 2 was logit (Model value) = 5.67+0.08 × Age −2.44 × log10 [the quantification of serum HBsAg (qHBsAg)] −0.60 × log10 [the quantification of serum HBeAg (qHBeAg)]+0.02 × ALT+0.03 ×  aspartate aminotransferase (AST). The area under the ROC curve (AUC) was 0.89 for the training group and 0.86 for the validation group. Using 2 cut-off points of −2.61 and 0.25, 59% of patients could be identified with liver fibrosis and antiviral treatment decisions were made without liver biopsies, and 149 patients were recommended to undergo liver biopsy for accurate diagnosis.In this study, the non-invasive model could predict liver fibrosis and may reduce the need for liver biopsy in HBeAg-positive CHB patients with normal or slightly increased ALT.  相似文献   
6.
AIDS and Behavior - We investigated the rate and predictors of ineffective HIV protection in men who have sex with men (MSM) taking pre-exposure prophylaxis (PrEP) in a prospective cohort study...  相似文献   
7.
目的 建立镍钛形状记忆合金骨板形状恢复能力测试方法.方法 首先确定镍钛形状记忆合金骨板形状恢复能力标准评价体系需要测试相变温度、形状恢复力、形状恢复率,然后分别建立骨板相变温度、形状恢复力、形状恢复率的标准测试方法.因各企业生产的镍钛形状记忆合金骨板形状结构不同,为保证测试方法的统一性,测试采用标准试样代替,试样使用原材料与被替代产品的原材料为同一批次,机械加工处理工艺保持一致.结果 根据已上市产品技术文件,镍钛形状记忆合金骨板相变温度Af点为37℃,产品形状恢复率应大于95%.按照本文提供的相变温度、形状恢复力、形状恢复率测试方法,试样测试时恢复至原始形状相对应的温度为37℃,即镍钛形状记忆合金骨板的Af点为37℃;依据镍钛形状记忆合金骨板临床使用时的温度,将试样测试温度设置为37℃,试样在31℃~37℃温度区间恢复力数据曲线一直上升,到达峰值后趋于稳定状态,通过数据分析,峰值的恢复力数据即镍钛形状记忆合金骨板工作时的形状恢复力,试样形状恢复力测试结果平均值为64.18 N;两种试样测试形状恢复率,并计算分析数据,所有试样形状恢复率均大于95%,与厂家提供的技术文件相符合.结论 结果说明提供的镍钛形状记忆合金骨板形状恢复能力(相变温度、形状恢复力、形状恢复率)的测试标准方法,可为企业的质量监管提供依据,为监管部门提供监管指南,按照测试方法通过测试评价后可保证产品临床使用的安全性.  相似文献   
8.
Dasabuvir (ABT-333) is a nonnucleoside inhibitor of the RNA-dependent RNA polymerase encoded by the hepatitis C virus (HCV) NS5B gene. Dasabuvir inhibited recombinant NS5B polymerases derived from HCV genotype 1a and 1b clinical isolates, with 50% inhibitory concentration (IC50) values between 2.2 and 10.7 nM, and was at least 7,000-fold selective for the inhibition of HCV genotype 1 polymerases over human/mammalian polymerases. In the HCV subgenomic replicon system, dasabuvir inhibited genotype 1a (strain H77) and 1b (strain Con1) replicons with 50% effective concentration (EC50) values of 7.7 and 1.8 nM, respectively, with a 13-fold decrease in inhibitory activity in the presence of 40% human plasma. This level of activity was retained against a panel of chimeric subgenomic replicons that contained HCV NS5B genes from 22 genotype 1 clinical isolates from treatment-naive patients, with EC50s ranging between 0.15 and 8.57 nM. Maintenance of replicon-containing cells in medium containing dasabuvir at concentrations 10-fold or 100-fold greater than the EC50 resulted in selection of resistant replicon clones. Sequencing of the NS5B coding regions from these clones revealed the presence of variants, including C316Y, M414T, Y448C, Y448H, and S556G, that are consistent with binding to the palm I site of HCV polymerase. Consequently, dasabuvir retained full activity against replicons known to confer resistance to other polymerase inhibitors, including the S282T variant in the nucleoside binding site and the M423T, P495A, P495S, and V499A single variants in the thumb domain. The use of dasabuvir in combination with inhibitors targeting HCV NS3/NS4A protease (ABT-450 with ritonavir) and NS5A (ombitasvir) is in development for the treatment of HCV genotype 1 infections.  相似文献   
9.
Wuchereria bancrofti prevalence and transmission were assessed in six endemic villages in Sikasso, Mali prior to and yearly during mass drug administration (MDA) with albendazole and ivermectin from 2002 to 2007. Microfilaremia was determined by calibrated thick smear of night blood in adult volunteers and circulating filarial antigen was measured using immunochromatographic card test in children < 5 years of age. Mosquitoes were collected by human landing catch from July to December. None of the 686 subjects tested were microfilaremic 12 months after the sixth MDA round. More importantly, circulating antigen was not detected in any of the 120 children tested, as compared with 53% (103/194) before the institution of MDA. The number of infective bites/human/year decreased from 4.8 in 2002 to 0.04 in 2007, and only one mosquito containing a single infective larva was observed 12 months after the final MDA round. Whether this dramatic reduction in transmission will be sustained following cessation of MDA remains to be seen.  相似文献   
10.
HMGB3, an X-linked member of the high-mobility group (HMG) superfamily of HMG proteins, has been shown to affect numerous tumorigenic progression. However, the expression and the prognostic role of HMGB3 in esophageal squamous cell carcinoma (ESCC) remained unknown. In this study, we examined the HMGB3 expression in ESCC tissues and adjacent nontumorous tissues by qRT-PCR and immuohistochemistry. Statistical analyses were applied to test for prognostic and diagnostic associations. The mRNA levels of HMGB3 were found to be significantly higher in tumorous tissues than in the adjacent normal tissues. We found that the HMGB3 expression was higher in tumorous tissues than in the adjacent non-tumorous tissues by immunohistochemical analysis of paired tissue specimens (P < 0.001). Moreover, there was a significant correlation between HMGB3 expression and gender (P = 0.037), clinical stage (P = 0.038), T classification (P = 0.013) and N classification (P = 0.017). Patients with higher HMGB3 expression had shorter overall survival than those with lower HMGB3 expression. Multivariate Cox analysis indicated that HMGB3 expression is an independent prognostic factor for overall survival (HR = 0.591, 95% CI = 0.379-0.793, P = 0.039). In summary, these findings demonstrate that HMBG3 may be a potential molecular marker for predicting the prognosis of ESCC patients.  相似文献   
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