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Melatonin induces apoptosis in many different cancer cell lines, including colorectal cancer. However, the precise mechanisms involved remain largely unresolved. In this study, we provide evidence to reveal a new mechanism by which melatonin induces apoptosis of colorectal cancer LoVo cells. Melatonin at pharmacological concentrations significantly suppressed cell proliferation and induced apoptosis in a dose‐dependent manner. The observed apoptosis was accompanied by the melatonin‐induced dephosphorylation and nuclear import of histone deacetylase 4 (HDAC4). Pretreatment with a HDAC4‐specific siRNA effectively attenuated the melatonin‐induced apoptosis, indicating that nuclear localization of HDAC4 is required for melatonin‐induced apoptosis. Moreover, constitutively active Ca2+/calmodulin‐dependent protein kinase II alpha (CaMKIIα) abrogated the melatonin‐induced HDAC4 nuclear import and apoptosis of LoVo cells. Furthermore, melatonin decreased H3 acetylation on bcl‐2 promoter, leading to a reduction of bcl‐2 expression, whereas constitutively active CaMKIIα(T286D) or HDAC4‐specific siRNA abrogated the effect of melatonin. In conclusion, the present study provides evidence that melatonin‐induced apoptosis in colorectal cancer LoVo cells largely depends on the nuclear import of HDAC4 and subsequent H3 deacetylation via the inactivation of CaMKIIα.  相似文献   
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刘林  李修红 《现代肿瘤医学》2020,(14):2443-2447
目的:肌少症对老年肝癌术后恢复及预后的影响。方法:选取2015年1月至2017年12月收治的114例老年肝癌,根据有无合并肌少症,分为肌少症组(n=35)和非肌少症组(n=79)。比较两组患者的术后恢复及生存情况。结果:肌少症组总并发症发生率、住院时间和30 d再入院率均高于对照组,差异均有统计学意义(P<0.05)。肌少症组中位生存时间为25.9个月,1年、2年、3年累积总生存率为74.3%、51.1%、24.5%,而非肌少症组中位生存时间为35.7个月,1年、2年、3年累积总生存率为87.3%、75.6%、49.4%,差异有统计学意义(P=0.004)。单因素分析结果显示,老年肝癌术后预后与Charlson合并症指数(CCI)、肌少症、巴塞罗那分期(BCLC)、甲胎蛋白、肿瘤大小、肿瘤个数、肿瘤分化程度、微血管侵犯(MVI)相关(P<0.05)。Cox多因素分析结果显示,CCI、肌少症、BCLC分期、肿瘤个数、MVI是老年肝癌术后预后的独立危险因素(P<0.05)。结论:肌少症会增加老年肝癌患者术后并发症发生率,延长住院时间,影响术后恢复,同时也会降低总生存率。  相似文献   
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目的研制加强型鼻咽通气道应用于五官科鼻腔手术后的气道管理。方法选取2014年1月至2015年3月行五官科鼻腔手术的患者60例,将其分为A组和B组,各30例。A组作为加强型鼻咽通气道组,术毕在膨胀止血海绵中放置加强型鼻咽通气道保留鼻腔通气;B组作为对照组,术毕采用传统单纯填塞膨胀止血海绵。通过术后24、48 h随访,对两组患者进行疼痛、睡眠质量、口干程度评分,并对其进行对比分析。结果加强型鼻咽通气道具有良好的抗压抗折性;A组患者24、48 h睡眠质量、口干程度评分均明显优于B组,差异均有统计学意义(P<0.05)。结论加强型鼻咽通气道用于五官科鼻腔手术后气道管理可增强气道管理安全性及患者舒适度。  相似文献   
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The objective of the present study was to evaluate the clinical, radiological, and functional outcomes of a subscapularis transthoracic surgical approach and a posterolateral surgical approach with debridement, bone graft fusion, and internal fixation for the treatment of upper thoracic tuberculosis.There is currently debate over the best surgical approach for the treatment of upper thoracic tuberculosis. Traditionally, the subscapularis transthoracic approach has been preferred; however, the posterolateral approach has gained popularity in the past few years.A prospective, consecutive cohort of 43 upper thoracic tuberculosis patients with a mean age of 39 years (range: 20–52 years) was followed up for a minimum of 12 months (range: 12–60 months). Patients were randomly divided into 2 groups. Group A (n = 21) was treated by the subscapularis transthoracic approach and group B (n = 22) was treated by the posterolateral approach. All cases were evaluated for clinical, radiological, and functional outcomes. Intraoperative blood loss, operative duration, intraoperative and postoperative complications, hospital stay, the cure rate, fusion time, and the Frankel scale were used for clinical and functional evaluation, whereas the kyphosis angle was used for radiological evaluation.Grafted bones were fused by 10 months in all cases. There was no statistically significant difference between groups before surgery in terms of gender, age, segmental tuberculosis, erythrocyte sedimentation rate (ESR), Frankel scale, or Cobb''s angle (P > 0.05). The average operative duration for Group B was lower than that of Group A. There were no significant differences in intraoperative blood loss, intraoperative and postoperative complications, hospital stay, grafted bone fusion time, or cure rate between groups (P > 0.05). The Cobb''s angle correction rate for group B (68.5%) was significantly better than that of group A (30.9%). The neurological score showed significant postoperative improvement in both groups, with no significant difference between the groups.The subscapularis transthoracic approach and the posterolateral approach with debridement, bone graft fusion, and internal fixation are both sufficient and satisfactory for the surgical treatment of upper thoracic tuberculosis. However, the posterolateral approach is superior to the subscapularis transthoracic approach in terms of surgical trauma, operative time, and kyphosis correction.  相似文献   
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目的回顾我院药物代谢酶和药物作用靶点相关基因检测与精准药学服务实践过程,总结经验,与同行分享。方法从准备工作、相关检测项目的确定,学术推广、项目优化和开展情况等方面详细阐述我院基因检测开展过程与精准药学服务情况。结果根据临床需求,我院已开展了以心脑血管药和抗精神病药为主的27种药物,26项检测,2018年全年位1587名患者提供个体化用药建议,受到临床医生和患者欢迎。结论基于代谢酶和药物作用靶点相关基因检测的个体化用药建议是临床药师参与精准治疗的重要途径,有助于医生和药师之间的沟通,有利于提高药学服务水平。  相似文献   
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BackgroundArtificial insemination with the husband’s semen (AIH) is an economical and noninvasive method of infertility treatment. However, AIH’s pregnancy rate is much lower than in vitro fertilization (IVF) as its multiple and complex uncertainty factors. Semen quality has been one of the main factors which affect the pregnancy outcome of AIH.MethodsThe relevant parameters of 1,142 AIH cycles were retrospectively studied, including the general parameters and the semen quality parameters among clinical pregnancy, biochemical pregnancy, non-pregnancy group, age, infertility duration, infertility type, body mass index (BMI), cycle count, morphology in previously semen examination, and semen quality parameters on the day of AIH.ResultsThe statistically significant difference was only found on processed total non-forward and non-motile sperm count (N-TFMSC). The mean processed N-TFMSC in the biochemical pregnancy group was 6.37±4.27 million, significantly higher than the other two groups (vs. 4.40±3.15 million or vs. 4.48±3.60 million, P<0.05). The study was then divided into two groups according to processed N-TFMSC, Group 1 ≤5.0 million, and Group 2 >5.0 million. A statistical increase in biochemical pregnancy rate was observed when the processed N-TFMSC was >5.0 million (2.72% vs. 0.90%).ConclusionsProcessed N-TFMSC may be one of the independent factors on AIH’s outcome; it should be given equal attention the same as processed total forward motile sperm count (TFMSC).  相似文献   
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目的通过对大鼠股骨骨折早期局部应用重组人骨保护素Fc融合蛋白(OPG-Fc),研究调节骨保护素(OPG)和核因子-κB受体活化因子配体(RANKL)的表达变化对骨折早期的影响,探讨其表达调节方式及作用机制。方法 48只雌性SD大鼠随机分成实验组和对照组,每组24只。建立大鼠股骨骨折模型,于术后第7天、第14天、第21天、第28天4个时间节段分批处死模型,标本切片后通过HE染色观察骨折愈合情况,免疫组织化学染色研究破骨细胞数量变化。结果 HE染色示单纯骨折组呈典型骨折愈合过程,而骨折局部注射OPG组骨痂形成及改造提前,骨折愈合加速。免疫组织化学染色显示在第7天、第14天、第21天、第28天各个时间节段单纯骨折组破骨细胞计数值均高于骨折应用OPG组,差异有统计学意义(P0.05)。结论骨折早期调节RANKL表达,当RANKL/OPG比值减小时,骨折局部破骨细胞减少,骨痂形成增多,骨折愈合加速。  相似文献   
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Vitamin D is responsible for multiple metabolic functions in humans. Rickets are the most common disease caused by vitamin D deficiency. It is caused by poor calcium intake resulting in poor serum-ionized calcium. The purpose of this study is to develop a rapid, sensitive, and feasible method to determine the 25-hydroxy-vitamin D3 (25(OH)D3) levels in blood samples for clinical assessment. In this study, gas chromatography coupled mass spectrometry with trimethylsilyl derivatization (TMS-GC-MS) is the most suitable protocol for quantitative analyses of 25(OH)D3. Performance of method was evaluated and compared with liquid chromatography and immunoassay. Method validation has been carried out with plasma specimens. The limit of quantitation of TMS-GC-MS method is 1.5 ppb with good linear correlation. Furthermore, the dietary intake and nutritional status of vegetarian and non-vegetarians in Taiwan were assessed by our validated method. As a result, this vitamin D nutrition survey demonstrates that most Taiwanese people have insufficient vitamin D. Due to dietary habits; the male vegans may have the highest risk of vitamin D deficiency.  相似文献   
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