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41.
目的: 探讨白藜芦醇联合顺铂对神经胶质瘤细胞C6 的作用。方法:不同浓度的白藜芦醇与顺铂单独联合
作用于神经胶质瘤细胞C6,24、48 h 和72 h 后,CCK8法检测增殖,并选出合适浓度进行后续试验;不同浓度的
药物作用于细胞24 h 后,吖啶橙法观察细胞形态变化、流式细胞仪检测细胞凋亡、细胞周期和免疫印迹检测蛋白
Bax、Bcl-2 和p-Erk1/2 变化。结果:白藜芦醇与顺铂能协同抑制神经胶质瘤细胞C6 的增殖。联合用药后细胞周
期抑制在S 期。免疫印迹结果显示凋亡蛋白Bax 的表达量增加,而凋亡抑制蛋白Bcl-2 的表达量减少,细胞外调
节蛋白激酶p-Erk1/2 的表达量减少。结论:白藜芦醇与顺铂联合对神经胶质瘤细胞具有相互增敏作用,能够协同
抑制细胞增殖,并通过Ras-Raf-MEK-Erk 信号通路促进其凋亡。 相似文献
42.
目的 探讨负荷渐增式训练对老年小鼠骨骼肌卫星细胞腺苷酸活化蛋白激酶(AMP-activated protein kinase,AMPK)磷酸化的影响。方法 实验小鼠分为 3 组:青年对照组(YC组,n=12)、老年对照组(OC组,n=12)与老年运动组(OT组,n=12)。OT组进行负荷渐增式训练,流式细胞分选技术分离CD45-/CD31-/Sca1-/VCAM(CD106)+细胞群体,分选细胞通过desmin、Myod肌原性染色以及成肌分化诱导培养进行肌卫星细胞鉴定,免疫组化结合Western blotting方法检测肌卫星细胞p-AMPK水平。结果 YC组骨骼肌卫星细胞AMPK及p-AMPK表达水平显著高于OC组(P<0.05);OT组与OC组AMPK表达无明显变化(P>0.05),而OT组p-AMPK表达水平显著高于OC组(P<0.05)。结论 负荷渐增式训练可促进老年小鼠骨骼肌卫星细胞AMPK磷酸化,改善老年小鼠骨骼肌能量代谢。 相似文献
43.
Matteo Morotti Christos E. Zois Rokaya El-Ansari Madeleine L. Craze Emad A. Rakha Shih-Jung Fan Alessandro Valli Syed Haider Deborah C. I. Goberdhan Andrew R. Green Adrian L. Harris 《British journal of cancer》2021,124(2):494
Background Glutamine (Gln) is an abundant nutrient used by cancer cells. Breast cancers cells and particularly triple-receptor negative breast cancer (TNBC) are reported to be dependent on Gln to produce the energy required for survival and proliferation. Despite intense research on the role of the intracellular Gln pathway, few reports have focussed on Gln transporters in breast cancer and TNBC.Methods The role and localisation of the Gln transporter SLC38A2/SNAT2 in response to Gln deprivation or pharmacological stresses was examined in a panel of breast cancer cell lines. Subsequently, the effect of SLC38A2 knockdown in Gln-sensitive cell lines was analysed. The prognostic value of SLC38A2 in a cohort of breast cancer was determined by immunohistochemistry.Results SLC38A2 was identified as a strongly expressed amino acid transporter in six breast cancer cell lines. We confirmed an autophagic route of degradation for SLC38A2. SLC38A2 knockdown decreased Gln consumption, inhibited cell growth, induced autophagy and led to ROS production in a subgroup of Gln-sensitive cell lines. High expression of SLC38A2 protein was associated with poor breast cancer specific survival in a large cohort of patients (p = 0.004), particularly in TNBC (p = 0.02).Conclusions These results position SLC38A2 as a selective target for inhibiting growth of Gln-dependent breast cancer cell lines.Subject terms: Breast cancer, Cancer metabolism 相似文献
44.
PurposeA meta-analysis aimed to systematically evaluate the safety and efficiency of I125 irradiation stent placement for patients with hepatocellular carcinoma (HCC) combined with portal vein tumor thrombosis (PVTT).Materials and methodsThe Cochrane library, PubMed/Medline, EMBASE, CNKI, Wanfang Data and CQVIP were systematically screened out from the earliest to December 2019. The qualities of all included studies were assessed. The primary endpoints were the 6-month, 12-month stent cumulative patency rate and 6-month, 12-month, 24-month overall survival rate while the secondary endpoints were the objective response rate of PVTT, main portal venous pressure changes and treatment-related adverse events. Our meta-analysis was conducted using Stata 12.0 software.ResultsTotally seven studies with 1018 patients were included in the final analysis, in which 602 patients received TACE and I125 irradiation stent placement, and 416 patients in control group underwent TACE and stent placement without endovascular brachytherapy (EVBT). Meta-analysis showed that the I125 irradiation stent improved the cumulative stent patency rates in 6 months [OR = 1.65, 95% CI (1.32–2.05), P < 0.001] and 12 months [OR = 2.55, 95% CI (1.90–3.42), P < 0.001] and the survival rates in 6 months [OR = 1.77, 95% CI (1.41–2.22), P < 0.001], 12 months [OR = 3.14, 95% CI (2.24–4.40), P < 0.001] and 24 months [OR = 7.39, 95% CI (3.55–15.41), P < 0.001]. However, there was no difference in the objective response rate of PVTT [OR = 1.13, 95% CI (0.87–1.48), P = 0.365], main portal venous pressure and the occurrence adverse event [OR = 0.88, CI = 0.72–1.08, P = 0.212] between two groups.ConclusionI125 irradiation stent seems to be more effective in treating hepatocellular carcinoma with portal vein tumor thrombosis. The usage of portal vein stent combined endovascular brachytherapy has the potential to act as an alternative therapy for HCC with PVTT. On account of the limitation of studies included, more studies with high-level evidence, such as RCTs, are requisite to support the above promising results. 相似文献
45.
Yang Luan Yan Zhang Kai Cui Fan Li Baolong Qin Yajun Ruan Kun Tang Hongyang Jiang Hao Li Xiaoyi Yuan Zhuo Liu Xiaming Liu Gan Yu Shengfei Xu Ruibao Chen Huan Yang Xiaolin Guo Xiaoyong Zeng Zhong Chen Zhiqiang Chen Zhiquan Hu Xiaodong Song Zhihua Wang Shaogang Wang Jihong Liu Tao Wang 《Translational andrology and urology》2021,10(1):466
BackgroundTo introduce and determine the value of optimized strategies for the management of urological tube-related emergencies with increased incidence, complexity and operational risk during the global spread of coronavirus disease 2019 (COVID-19).MethodsAll emergent urological patients at Tongji Hospital, Wuhan, during the period of January 23 (the beginning of lockdown in Wuhan) to March 23, 2020, and the corresponding period in 2019 were recruited to form this study’s COVID-19 group and control group, respectively. Tongji Hospital has the most concentrated and strongest Chinese medical teams to treat the largest number of severe COVID-19 patients. Patients in the control group were routinely treated, while patients in the COVID-19 group were managed following the optimized principles and strategies. The case incidence for each type of tube-related emergency was recorded. Baseline characteristics and management outcomes (surgery time, secondary complex operation rate, readmission rate, COVID-19 infection rate) were analyzed and compared across the control and COVID-19 periods.ResultsThe total emergent urological patients during the COVID-19 period was 42, whereas during the control period, it was 124. The incidence of tube-related emergencies increased from 53% to 88% (P<0.001) during the COVID-19 period. In particular, the incidence of nephrostomy tube-related (31% vs. 15%, P=0.027) and single-J stent-related problems (19% vs. 6%, P=0.009) increased significantly. The mean surgery times across the two periods were comparable. The number of secondary complex operations increased from 12 (18%) to 14 (38%) (P=0.028) during the COVID 19-period. The number of 2-week postoperative readmission decreased from 10 (15%) to 1 (3%) (P=0.049). No participants contracted during the COVID-19 period.ConclusionsUrological tube-related emergencies have been found to have a higher incidence and require more complicated and dangerous operations during the COVID-19 pandemic. However, the optimized management strategies introduced in this study are efficient, and safe for both urologists and patients. 相似文献
46.
Dianping You Fang Chen Jingjie Li Xianping Zeng Weijian Wang Yinghui Guo Fan Yang Suzhen Sun Le Wang 《Journal of clinical laboratory analysis》2021,35(2)
BackgroundViral encephalitis is common in childhood. It is an acute brain parenchymal inflammation caused by a variety of viral infection, and enterovirus accounts for the majority. Due to atypical clinical manifestations, pathogenic testing is important for assisting clinical diagnosis. The purpose of this study was to evaluate the performance of the multiplex PCR assay compared with quantitative real‐time PCR for enterovirus detection.MethodsA prospective case‐control study was performed involving 103 pediatric patients suspected for viral encephalitis and cerebrospinal fluid (CSF) samples were collected and tested for 9 pathogens using multiplex PCR assay during April to November in 2018. In parallel, an aliquot of samples was tested for enterovirus infection by real‐time PCR assay.ResultsThere were 85.4% children were confirmed as viral encephalitis on discharge, the remaining ones were diagnosed as other CNS diseases, such as epilepsy. The specificity of the two methods was the same as that of the clinical diagnosis, but the sensitivity and consistency with clinical diagnosis of multiplex PCR were both higher than the real‐time PCR. Besides of enterovirus, multiplex PCR could also detect coinfection of enterovirus with Epstein‐Barr virus and mumps virus.ConclusionResults of multiplex PCR method are more consistent with the clinical diagnosis and are superior to real‐time PCR for detecting enterovirus in CSF. 相似文献
47.
目的 探讨青年学生性健康知信行自我分类偏差对相关问题求助意愿的影响,为精准实施青年学生性健康促进提供科学依据。方法 2019年3-4月性健康和HIV感染风险评估干预微信小程序("熊探")测试期间的青年学生使用者纳入为研究对象。根据研究对象性健康知信行的自我分类和系统分类结果差异划分为3组,包括分类一致组、自我分类偏低组(自评比实际性资讯获取更少、性态度更传统、性经历更少)和自我分类偏高组(自评比实际性资讯获取更多、性态度更开放、性经历更多)。采用logistic回归分析3组研究对象的性健康相关问题求助意愿差异。结果 2 009名研究对象的年龄(19.2±1.1)岁,女性占54.7%(1 099/2 009),大专及以上者占98.4%(1 976/2 009)。性健康知信行自我分类一致、偏低和偏高者分别占49.0%(984/2 009)、10.9%(219/2 009)和40.1%(806/2 009)。与分类一致者相比,自我分类偏低青年学生的HIV自愿咨询检测服务接受意愿更低(aOR=0.65,95%CI:0.43~0.99),自我分类偏高青年学生的性相关疾病求助意愿更低(aOR=0.76,95%CI:0.59~0.98)。结论 性健康知信行自我分类偏差会降低青年学生对相关问题的求助意愿,尤其自我分类偏低会使青年学生低估HIV感染风险,接受咨询检测意愿下降,引起青年学生艾滋病疫情加速扩散。在性健康教育中需加强引导,提高青年学生群体自我评估能力、客观感知和应对风险。 相似文献
48.
49.
50.
P. Shen Y. Zhou A. Song Y. Wan Z. Fan R. Xu 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2021,31(8):2376-2381
Background and aimsWe aimed to evaluate the association between different obese phenotypes with carotid artery plaque (CAP) event.Method and resultsThe current retrospective cohort study was performed in 32,778 Chinese adults (19,221 men and 13,557 women, aged 41.9 ± 11.0 years). Obese phenotypes were assessed based on baseline body mass index (<24.0 vs. ≥24.0 kg/m2) and metabolic characteristics (health vs. unhealth). All the participants were further classified into four groups: metabolic health and normal weight (MHNW), metabolic unhealth and normal weight (MUHNW), metabolic health and overweight (MHO), and metabolic unhealth and overweight (MUHO). Ultrasound B-mode imaging was annually performed to evaluate CAP throughout the study. We have identified 2142 CAP cases during 5-year follow-up. Comparing with the MHNW group, the hazard ratios for the risk of incident CAP was 2.44 (95% CI:1.92 and 3.09) for the MUHNW group, 1.52 (95% CI:1.06 and 2.18) for the MHO group, and 1.8 (95% CI:1.4 and 2.33) for the MUHO group. The association was more pronounced in young adults (<65 y) than that in aged adults (≥65 y). Sensitivity analysis generated similar results with the main analysis.ConclusionMUHNW, MHO, and MUHO were associated with the risk of CAP. 相似文献