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31.
32.
背景与目的:Musashi1(Msi1)属于RNA结合蛋白家族中的一员,是RNA转录后表达的关键调控者,其是否参与肿瘤的发生、发展,以及具体分子机制仍不十分清楚。探讨沉默Msi1基因对结肠癌HCT116细胞恶性生物学行为的影响及可能的机制。方法:采用慢病毒载体构建稳定低表达Msi1的细胞株,细胞计数试剂盒(cell counting kit-8,CCK-8)实验检测细胞增殖能力,克隆形成实验检测细胞克隆形成能力,流式细胞术(flow cytometry,FCM)检测细胞周期的变化,裸鼠移植瘤模型观察沉默Msi1对裸鼠成瘤的影响。实时荧光定量聚合酶链反应(real-time fluorescence quantitative polymerase chain reaction,RTFQ-PCR)和蛋白质印记法(Western blot)检测沉默Msi1基因后p27基因的mRNA表达和蛋白水平,双荧光素酶实验验证Msi1基因与目的基因p27 3’-非编码区(3’-untranslated region,3’-UTR)的相互作用。结果:沉默Msi1基因后,HCT116细胞的增殖能力显著下降,克隆集落数明显减少,G 0 /G 1 期细胞增多,S期细胞明显减少,裸鼠移植瘤生长明显受到抑制。沉默Msi1基因后p27 mRNA表达未见明显变化,而p27蛋白水平明显上调,双荧光素酶实验证实Msi1基因能与p27 3’-UTR区域直接结合,抑制其翻译。结论:沉默Msi1基因通过靶向上调p27,导致结肠癌HCT116细胞G 0 /G 1 期阻滞,从而抑制肿瘤细胞体内及体外增殖能力。  相似文献   
33.
《药学学报(英文版)》2020,10(2):327-343
Our recent studies demonstrated that the natural product nobiletin (NOB) served as a promising multidrug resistance (MDR) reversal agent and improved the effectiveness of cancer chemotherapy in vitro. However, low aqueous solubility and difficulty in total synthesis limited its application as a therapeutic agent. To tackle these challenges, NOB was synthesized in a high yield by a concise route of six steps and fourteen derivatives were synthesized with remarkable solubility and efficacy. All the compounds showed improved sensitivity to paclitaxel (PTX) in P-glycoprotein (P-gp) overexpressing MDR cancer cells. Among them, compound 29d exhibited water solubility 280-fold higher than NOB. A drug-resistance A549/T xenograft model showed that 29d, at a dose of 50 mg/kg co-administered with PTX (15 mg/kg), inhibited tumor growth more effective than NOB and remarkably increased PTX concentration in the tumors via P-gp inhibition. Moreover, Western blot experiments revealed that 29d inhibited expression of NRF2, phosphorylated ERK and AKT in MDR cancer cells, thus implying 29d of multiple mechanisms to reverse MDR in lung cancer.  相似文献   
34.
ABSTRACT

Undocumented Mexican immigrants have had to regularly confront a prohibiting health care system despite alienation, marginalization, and the threat of deportation. In this article, I explore the impact of political exclusion and alienating discourses on the health habitus of undocumented Mexican mothers through the narrative of one mother, Marta Garza, who finds herself at the painful intersection of political and medical alienation. Marta’s narrative reflects an analytical framework that centers undocumented motherhood as a space of necessary resilience and strain, wherein she is forced to advocate for her children’s health despite prohibitive barriers and dangerous potential consequences.  相似文献   
35.

Objective

To evaluate the impact of the Youth Form Strategy (EFJ, Estrategia Forma Joven) on the attitudes and behaviours of students in the fourth year of compulsory secondary school in Seville, Spain.

Methods

A longitudinal observational design was used with two groups; one received the EFJ (EFJ group) and other did not (non-EFJ group). In the initial evaluation, 402 participants were randomly selected and, in the follow-up at 6 months, 322 participants were evaluated (161 per group). Validated data collection tools were used, and 2 × 2 tables, odds ratio (OR) and general ANOVA for 2 × 2 mixed factorial design (p < 0.05) were calculated.

Results

Favourable effects of the EFJ were found: in the area of sexuality, the percentage of participants who had sexual intercourse in the final assessment was lower in the EFJ group (14.9% vs 23.4%; OR = 0.57), as were counter-effects: start of tobacco use was higher in the EFJ group (19.5% vs 9.1%; OR = 2.43). However, these differences were not statistically significant.

Conclusions

The similarities in the school health promotion programme in centres with and without EFJ may have influenced the lack of conclusive results. Individual and/or group counselling at schools, a distinguishing feature of the EFJ, could have delayed sexual intercourse in the EFJ group. Based on the studies on school health promotion activities, good practices that could help to improve the effectiveness of the EFJ are recommended.  相似文献   
36.
ObjectiveWe analyse how reproductive health strategies have been incorporated into the everyday activities of the services and the resulting transformation of professional and user practices.MethodCartographic research taking a multi-sited ethnographic approach that seeks to reveal the processes of transformation. Data generation techniques featuring participant observation and situated interviews. Discourse analysis of the text corpus using three analytical axes based on three main lines of action promoted by the strategies.ResultsWe identified transformations in: 1) demedicalisation: an increase in midwives’ know-how and autonomy, changes in episiotomy practice and the facilitation of bonding practices; 2) warmth of care: incorporation of women's needs and expectations and improvements in the comfortableness of birth settings, especially in assistance at physiological birth; and 3) participation: actions that foster shared decision-making and the involvement of the persons accompanying women in labour.ConclusionsAbove all, transformation is visible in the incorporation of new attitudes, sensibilities and practices that have developed around the old structures, especially during physiological childbirth. The more technological areas have been less permeable to change. Risk management in decision-making and addressing diversity are identified as areas where transformation is less evident.  相似文献   
37.
目的探讨复杂人工全膝关节置换术(total knee arthroplasty,TKA)中采用股直肌斜切辅助显露的安全性及有效性。方法回顾分析 2016 年 1 月—2017 年 5 月,采用股直肌斜切辅助显露的 19 例(29 膝)复杂 TKA 患者临床资料。其中男 9 例(13 膝),女 10 例(16 膝);年龄 34~66 岁,平均 50.2 岁。强直性脊柱炎 4 例(8 膝),类风湿性关节炎 5 例(7 膝),膝关节骨关节炎 10 例(14 膝)。病程 8~15 年,平均 10.9 年。Kellgren-LawrenceⅢ级 12 膝,Ⅳ级 17 膝。患者膝关节活动度为(19.86±7.23)°,膝关节学会评分系统(KSS)临床评分(47.86±11.26)分、功能评分(15.52±11.21)分。术后随访纳入并发症、膝关节活动度、KSS 评分、伸膝迟滞发生情况及假体松动情况。结果术后切口均Ⅰ期愈合,无感染及心脑血管意外等并发症发生。患者均获随访,随访时间 25~39 个月,平均 30.3 个月。末次随访时,患者膝关节活动度为(91.03±7.30)°,KSS 临床评分为(83.62±9.99)分、功能评分为(66.38±7.89)分,均较术前明显改善,差异有统计学意义(P<0.05)。3 膝出现伸膝迟滞,分别迟滞 10°、10°、15°。X 线片复查未见假体位置不良、松动及病理性透亮线。 结论复杂 TKA 中采用股直肌斜切能有效显露膝关节术野,减少髌腱撕脱、髌骨骨折以及股四头肌肌腱损伤等并发症的发生;采用 Krackow 肌腱缝合法修复切断的股直肌有利于术后早期膝关节功能锻炼及恢复,而且不会增加并发症发生风险。  相似文献   
38.
Sorafenib provides survival benefits in patients with advanced renal cell carcinoma (RCC), but its use is hampered by acquired drug resistance. It is important to fully clarify the molecular mechanisms of sorafenib resistance, which can help to avoid, delay or reverse drug resistance. Extracellular vesicles (EVs) can mediate intercellular communication by delivering effector molecules between cells. Here, we studied whether EVs are involved in sorafenib resistance of RCC and its possible molecular mechanisms. Using differential centrifugation, EVs were isolated from established sorafenib-resistant RCC cells (786-0 and ACHN), and EVs derived from sorafenib-resistant cells were uptaken by sensitive parental RCC cells and thus promoted drug resistance. Elevated exogenous miR-31-5p within EVs effectively downregulated MutL homolog 1 (MLH1) expression and thus promoted sorafenib resistance in vitro. Mice experiments also confirmed that miR-31-5p could mediate drug sensitivity in vivo. In addition, low expression of MLH1 was observed in sorafenib-resistant RCC cells and upregulation of MLH1 expression restored the sensitivity of resistant cell lines to sorafenib. Finally, miR-31-5p level in circulating EVs of RCC patients with progressive disease (PD) during sorafenib therapy was higher when compared to that in the pretherapy status. In conclusion, EVs shuttled miR-31-5p can transfer resistance information from sorafenib-resistant cells to sensitive cells by directly targeting MLH1, and thus magnify the drug resistance information to the whole tumor. Furthermore, miR-31-5p and MLH1 could be promising predictive biomarkers and therapeutic targets to prevent sorafenib resistance.  相似文献   
39.
目的探讨miRNA let-7a调控高迁移率族蛋白2(HMGA2)对人喉鳞癌细胞株TU212增殖的影响。方法合成let-7a模拟体(let-7a mimics)并采用阳离子脂质体法瞬时转染入喉癌TU212细胞,裸鼠皮下注射TU212细胞,构建裸鼠移植瘤模型。RT-qPCR和Western blot法分别检测转染后TU212细胞及移植瘤内let-7a和HMGA2的表达。结果在过表达let-7a的喉癌TU212细胞中,HMGA2的转录和翻译水平下调,细胞增殖能力降低。体外成瘤实验证实,与let-7a NC组和空白对照组相比,转染let-7a mimics的喉癌细胞TU212成瘤组织的质量和体积均显著下降;let-7a过表达的TU212成瘤组织中HMGA2的mRNA和蛋白水平均明显下调。结论let-7a能显著抑制HMGA2的mRNA和蛋白表达,进而显著抑制喉癌细胞的增殖。  相似文献   
40.
目的:探讨miR-361-5p对肾细胞癌ACHN细胞增殖、侵袭、迁移、凋亡及其细胞周期的影响。方法:将miR-361-5p mimics和miR-361-5p inhibitor分别转染至肾癌ACHN细胞中,用qPCR检测转染细胞中miR-361-5p的表达水平,用MTT法、划痕愈合实验、Transwell实验、流式细胞术分别检测细胞的增殖、迁移、侵袭、细胞周期和凋亡水平。结果:与空白对照组和 Mimics-NC组比较,miR-361-5p mimics组ACHN细胞中miR-361-5p表达水平显著升高(P<0.01),细胞的增殖、侵袭和迁移能力均显著减弱(均P<0.01),而凋亡率升高(P<0.01)。与空白对照组或Inhibitor-NC组比较,miR-361-5p inhibitor组细胞中miR-361-5p表达水平显著下降(P<0.01),细胞的增殖、侵袭和迁移能力均增强(均P<0.01),细胞周期运转加速(P<0.01),凋亡率降低(P<0.05)。结论:miR-361-5p可抑制肾癌ACHN细胞的增殖、侵袭和迁移,并诱导细胞凋亡,其在肾癌发生发展过程中发挥重要的抑制作用。  相似文献   
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