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951.
目的: 应用RNA-Seq技术分析与施万细胞共培养前、后的唾液腺腺样囊性癌细胞(SACC)的基因表达水平变化,明确嗜神经侵袭(perineural invasion,PNI)相关基因。 方法: 采用腺样囊性癌与SD大鼠施万细胞共培养模型,分析共培养前、后SACC细胞基因表达变化,对差异表达基因进行聚类分析、GO功能富集分析、KEGG通路富集分析,并采用qRT-PCR对其中6个关键差异表达基因进行验证。采用edgeR软件(3.12.1)进行表达差异显著性分析,将P≤0.05、差异表达倍数的绝对值大于1作为差异显著性标准。 结果: 在腺样囊性癌单独培养组与共培养组之间发现395个差异表达基因(P≤0.05,|logFC|≥1.0),其中135个基因上调(34.2%),260个基因下调(65.8%)。GO功能富集分析结果表明,这些PNI相关差异表达基因参与了血管再生、细胞外基质的组成、细胞增殖、凋亡和上皮形态发生;KEGG通路富集分析结果表明,这些基因参与组氨酸代谢、肿瘤坏死因子、趋化因子等细胞因子受体相互作用等重要生物学通路。利用qRT-PCR技术对其中6个关键基因进行验证,验证结果与RNA-Seq趋势一致。 结论: 得到了SACC嗜神经侵袭PNI的相关差异基因,为阐明SACC的嗜神经侵袭机制提供了实验依据。 相似文献
952.
目的观察辣椒素对人大细胞肺癌NCI-H460细胞侵袭能力及E-钙黏蛋白(E-cadherin)和Snail蛋白表达的影响,探讨其抗非小细胞肺癌的可能机制。方法体外培养NCI-H460细胞,以不同终浓度辣椒素进行处理,未加辣椒素为对照组。采用Hoechst33342核染色分析、Transwell小室细胞侵袭实验及Western blot检测,观察辣椒素对NCI-H460细胞凋亡、侵袭能力及E-cadherin、Snail蛋白表达变化的影响。结果与对照组比较,Hoechst33342核染色分析表明,辣椒素各浓度组可明显诱导NCI-H460细胞凋亡(P0.05);Transwell体外侵袭实验结果显示,辣椒素可显著抑制侵袭穿膜细胞数(P0.05);Western blot检测结果表明,辣椒素各浓度组E-cadherin表达水平明显升高、Snail表达水平明显降低(P0.05)。结论辣椒素能明显诱导NCI-H460细胞凋亡;降低Snail表达、刺激E-cadherin的表达从而抑制NCI-H460细胞侵袭能力,可能是其抗非小细胞肺癌的机制之一。 相似文献
953.
涎腺腺样囊性癌嗜神经侵袭分子机制的研究进展 总被引:1,自引:0,他引:1
涎腺腺样囊性癌是发生于涎腺的一种非常常见的恶性肿瘤,其重要特质是嗜神经侵袭,这一特质是其在临床手术中很难被彻底切除的重要原因之一;部分肿瘤细胞的残留易导致肿瘤术后复发,成为临床治疗的一大难题。因此,深入探讨涎腺腺样囊性癌嗜神经侵袭这一特性的分子机制对克服这一难题具有重要意义,本文就涎腺腺样囊性癌嗜神经侵袭分子机制的研究进展作一综述。 相似文献
954.
Whole genome sequence and phenotypic characterization of a Cbm+ serotype e strain of Streptococcus mutans
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A. Avilés‐Reyes I. A. Freires J.K. Kajfasz D. Barbieri J.H. Miller J.A. Lemos J. Abranches 《Molecular oral microbiology》2018,33(3):257-269
We report the whole genome sequence of the serotype e Cbm+ strain LAR01 of Streptococcus mutans, a dental pathogen frequently associated with extra‐oral infections. The LAR01 genome is a single circular chromosome of 2.1 Mb with a GC content of 36.96%. The genome contains 15 phosphotransferase system gene clusters, seven cell wall‐anchored (LPxTG) proteins, all genes required for the development of natural competence and genes coding for mutacins VI and K8. Interestingly, the cbm gene is genetically linked to a putative type VII secretion system that has been found in Mycobacteria and few other Gram‐positive bacteria. When compared with the UA159 type strain, phenotypic characterization of LAR01 revealed increased biofilm formation in the presence of either glucose or sucrose but similar abilities to withstand acid and oxidative stresses. LAR01 was unable to inhibit the growth of Strpetococcus gordonii, which is consistent with the genomic data that indicate absence of mutacins that can kill mitis streptococci. On the other hand, LAR01 effectively inhibited growth of other S. mutans strains, suggesting that it may be specialized to outcompete strains from its own species. In vitro and in vivo studies using mutational and heterologous expression approaches revealed that Cbm is a virulence factor of S. mutans by mediating binding to extracellular matrix proteins and intracellular invasion. Collectively, the whole genome sequence analysis and phenotypic characterization of LAR01 provides new insights on the virulence properties of S. mutans and grants further opportunities to understand the genomic fluidity of this important human pathogen. 相似文献
955.
Małek ŁA Śpiewak M Kłopotowski M Miśko J Rużyłło W Witkowski A 《European journal of radiology》2012,81(10):2839-2843
Background
Microvascular obstruction (MVO) is a cardiac magnetic resonance (CMR) marker of no-reflow in ST-segment elevation myocardial infarction (STEMI). It remains unresolved whether the infarct size corresponds only to the presence of MVO or also to its extent.Methods
The study included 53 patients with first STEMI (median age 61.5 years, 77% male) treated with percutaneous coronary intervention (PCI) who underwent CMR after median 5 days from PCI. Small MVO was defined as patchy, non-confluent spots of dark areas of absent contrast surrounded by late gadolinium enhancement (LGE). Large MVO was defined as confluent areas of MVO comprising a large amount of the infarct zone.Results
Microvascular obstruction was observed in 32 patients (60%) including 18 patients with small MVO (36%) and 14 patients with large MVO (24%). Patients with MVO were more likely to have TIMI 0/1 grade flow on initial angiogram, higher levels of necrotic markers, larger infarct size, larger left ventricular end-diastolic and end-systolic volume and lower ejection fraction in comparison to patients without MVO. These differences were not observed between patients with large and small MVO.Conclusions
The presence of MVO but not its extent corresponds to larger infarct size in STEMI. 相似文献956.
目的:探讨在体内外环境下缺氧诱导因子1α(HIF-1α)过表达对前列腺癌细胞发生上皮间质转化(EMT)并导致肿瘤侵袭能力升高的影响。方法:对已构建的稳定表达HIF-1α的人前列腺癌LNCaP细胞(LN-CaP/HIF-1α)复苏后培养,对HIF-1α过表达进行鉴定。MTT法测定细胞增殖;检测转染前后培养液上清PSA水平;软琼脂成瘤实验比较两种细胞体外成瘤能力;将转染前后的LNCaP细胞注射免疫裸鼠皮下建立皮下肿瘤模型,观察肿瘤生长情况;收集肿瘤标本进一步行免疫组化处理。结果:免疫荧光和Western印迹证实LNCaP/HIF-1α细胞中HIF-1α过表达。同LNCaP细胞相比,转染HIF-1α的人前列腺癌LNCaP细胞培养液中PSA水平明显降低;MTT法显示其更具有增殖活性,体外成瘤能力更强。体内实验显示皮下肿瘤成瘤率提高,成瘤时间提前。肿瘤标本免疫组化提示转染组E钙粘蛋白表达下调,波形蛋白表达上调。结论:HIF-1α过表达能够封闭E钙粘蛋白,上调波形蛋白表达,提示HIF-1α过表达可能通过诱导EMT增强LNCaP细胞侵袭能力。 相似文献
957.
Study Type – Prognosis (case series) Level of Evidence 4 What's known on the subject? and What does the study add? In an array of urological and non‐urological malignancies, lymphovascular invasion (LVI) is a pathological feature known to be associated with adverse outcomes for recurrence and survival. For some cancers, LVI has therefore been incorporated into American Joint Committee on Cancer TNM staging algorithms. This study presents an analysis of the impact of LVI in upper urinary tract urothelial carcinoma (UTUC) treated at our institution over a 20‐year period. In addition to known associations with features of aggressive disease and overall survival, we were able to show that LVI‐positive status upsets the TNM staging for UTUC. Namely, patients with superficial stage and LVI‐positive disease have overall survival outcomes similar to those of patients with muscle‐invasive LVI‐negative carcinoma. Such evidence may support the addition of LVI to future TNM staging algorithms for UTUC.
OBJECTIVE
- ? To assess the impact of lymphovascular invasion (LVI) on the prognosis of patients with upper urinary tract urothelial cell carcinoma (UTUC) treated with radical nephroureterectomy (RNU).
PATIENTS AND METHODS
- ? The Columbia University Medical Center Urologic Oncology database was queried and 211 patients undergoing RNU for UTUC between 1990 and 2010 were identified.
- ? These cases were retrospectively reviewed, and the prognostic significance of relevant clinical and pathological variables was analysed using log‐rank tests and Cox proportional hazards regression models.
- ? Actuarial survival curves were calculated using the Kaplan–Meier method.
RESULTS
- ? LVI was observed in 68 patients (32.2%).
- ? The proportion of LVI increased with advancing stage, high grade, positive margin status, concomitant carcinoma in situ, and lymph node metastases. The 5‐ and 10‐year overall survival rates were 74.7% and 53.1% in the absence of LVI, and 35.7% and 28.6% in the presence of LVI, respectively.
- ? In multivariate analysis, age, race and LVI were independent predictors of overall survival.
CONCLUSIONS
- ? The presence of LVI on pathological review of RNU specimens was associated with worse overall survival in patients with UTUC.
- ? LVI status should be included in the pathological report for RNU specimens to help guide postoperative therapeutic options.
- ? With confirmation from large international studies, inclusion of LVI in the tumour‐node‐metastasis staging system for UTUC should be considered.
958.
微创椎弓根螺钉内固定术是一项新的脊柱微创技术。近年来逐渐应用于胸腰椎骨折、腰椎失稳等疾病的治疗,并得到推广应用,其具有切口小、创伤小、出血少、术后恢复快等优点。该文就其临床应用进展进行综述。 相似文献
959.
根据中国疾病预防控制中心传染病预防控制所(2004年)列出的蚊类、蝇类和蜚蠊类需要进行监测的种类和最新的地理分布资料,讨论了国际交流与我国目前主要媒介昆虫的关系。我国所需要监测媒介昆虫绝大多数为世界性分布,而且在世界上的扩散十分迅速。结合近年来我国出入境检验检疫局发布的信息及国际媒介生物扩散信息,推断这种扩散是由于人类的国际间活动所致。 相似文献
960.
目的 观察复方聚乙二醇电解质散溶液不同口服速度对肠道清洁的效果.方法 将180例行结肠镜检查的患者按随机数字表分成A、B、C组,每组60例.服药方法:将2包复方聚乙二醇电解质散用2 000 ml温开水冲调后,A组在1 h内服完,B组在2 h内服完,C组在3 h内服完.观察患者服药后不良反应发生情况,在肠镜检查时进行肠道清洁质量总体评分.结果 A组肠道清洁质量总体评分优于B组、C组,P<0.01;肠道准备质量:右侧结肠清洁度A组与B、C组比较有统计学意义(P<0.01),中间结肠清洁度3组组间比较无统计学意义,左侧结肠清洁度A组与B、C组比较有统计学意义(P<0.05).A组5例出现腹胀、呕吐;B组3例患者出现腹胀,没有呕吐;C组无明显不良反应发生.结论 1 h内服完复方聚乙二醇电解质散药液,肠道清洁效果最好. 相似文献