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1.
目的 Dof(DNA binding with one finger)家族是高等植物中特有的一类转录因子家族,参与植物中光、激素、非生物胁迫等多种胁迫响应调控。本研究基于全基因组数据对黄花蒿Dof(AaDof)转录因子家族进行鉴定及表达模式分析,探究Dof家族基因在青蒿素合成调控中的作用。方法 经PFAM数据库鉴定获得AaDof序列,通过生物信息学软件分析其理化性质、亚细胞定位、基因结构、蛋白保守结构以及启动子序列结合元件等,并基于赤霉素(Gibberellic acid, GA)、紫外线B(UV-B)及二者协同胁迫下黄花蒿转录组数据对其表达模式进行分析。结果 本研究从全基因组水平共鉴定出51个AaDof基因,均含有保守的C2-C2单锌指结构,依据系统发育分析分为8个亚族,同一亚族内基因结构与蛋白保守结构域相对保守。亚细胞定位预测显示12个AaDof蛋白定位在细胞外,其余均定位在细胞核。启动子元件分析发现AaDof家族基因启动子区富含光、激素等多种响应元件。对AaDof在GA、UV-B和GA+UV-B处理下的表达模式分析发现,AaDof基因对GA胁迫处理响应较弱,仅有少量基因敏感,其表达主要受到UV-B胁迫影响。C1及C2.1亚族大部分基因在UV-B胁迫下上调表达,而A亚族大部分基因在UV-B胁迫下下调表达。qRT-PCR验证表明AaDof1AaDof17AaDof44在GA和UV-B处理下表达量显著上调,推测其可能通过参与GA和UV-B调控网络,正向调控青蒿素生物合成。结论 本研究系统鉴定了黄花蒿AaDof家族基因并筛选了3个可能正向调控青蒿素生物合成的候选AaDof基因,为黄花蒿Dof家族基因功能研究及其在青蒿素生物合成中的调控机制解析奠定基础。  相似文献   
2.
The pituitary tumor-transforming gene 1 (PTTG1), also known as Securin, is considered an oncogene. This study aimed to investigate the role of PTTG1 in clear cell renal cell carcinoma (ccRCC) using in silico bioinformatics approaches. A pan-cancer analysis using The Cancer Genome Atlas (TCGA) data indicated that among all cancer types copy number amplification of PTTG1 gene was most frequently found in ccRCC. However, amplification of PTTG1 gene copy number did not correlate with the increase of mRNA level in ccRCC, and did not predict the patients' overall survival. Instead, ccRCC was correlated with overexpression of PTTG1 mRNA, and its expression level was stage-dependent increased in cancer patients. An outlier analysis using the Oncomine database suggested that PTTG1 mRNA expression served as a good biomarker for ccRCC. Pathway analysis for upregulated genes enriched in PTTG1-high expressing ccRCC patients found that PTTG1 overexpression was associated with mitotic defects. Mining drug sensitivity data using the Cancer Therapeutics Response Portal (CTRP) discovered that PTTG1-high expressing ccRCC cell lines were susceptible to a Rac1 (Ras-related C3 botulinum toxin substrate 1) inhibitor NSC23766. Therefore, this study provides an in silico insight into the role of PTTG1 in ccRCC, and repurposes the Rac1 inhibitor NSC23766 for treating PTTG1-high expressing ccRCC.  相似文献   
3.
目的:探究并分析加味香砂六君子汤通过抑制Wnt信号通路对胃癌大鼠桩蛋白(paxillin)、大鼠凋亡相关蛋白(RelA)表达的影响。方法:选取健康成年Wistar大鼠120只,按照随机数字表法分为对照组和观察组,每组60只,对2组大鼠进行胃癌造模处理,对照组大鼠又随机分为未处理组、处理(生理盐水)后8周组、处理(生理盐水)后12周组,每组20只。观察组大鼠又随机分为未处理组、处理(汤药)后8周组、处理(汤药)后12周组,每组20只。观察2组大鼠处理前、处理后8周、处理后12周paxillin、RelA。结果:2组大鼠处理前后体质量差异有统计学意义(P<0.05),2组大鼠处理前体质量比较差异无统计学意义(P>0.05),处理后,2组大鼠体质量有所降低,但观察组大鼠降低程度明显小于对照组(P<0.05);2组大鼠处理前后wnt-1、paxillin、RelA水平差异有统计学意义(P<0.05),2组大鼠处理前wnt-1、paxillin、RelA水平比较差异无统计学意义(P>0.05),处理后,2组大鼠wnt-1、paxillin、RelA水平呈降低趋势,但观察组大鼠wnt-1、paxillin、RelA水平明显小于对照组,差异有统计学意义(P<0.05)。结论:加味香砂六君子汤能有效通过抑制wnt以降低胃癌大鼠paxillin、RelA的表达。  相似文献   
4.
Cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC) is the fourth commonest female malignancy worldwide. CESC progresses in immune-microenvironment mainly composed of infiltrating immune and stromal cells. Here, we performed an integrated analysis incorporating the expression profiles from the Cancer Genome Atlas (TCGA) database and scores of immune and stromal cells calculated by Estimation of Stromal and Immune cells in Malignant Tumours using Expression data (ESTIMATE) algorithm. A two-gene signature (CD1C and CD6 genes) was established to predict the prognosis of CESC. Based on this signature, patients were divided into the high- and low-risk groups, and this signature showed good prognostic performance according to the results of Kaplan-Meier analysis and receiver operating characteristic (ROC) analysis in train set and two validation sets. A nomogram was built for evaluating the clinical applicability of this signature. In addition, based on Tumor Immune Estimation Resource (TIMER) database, 2 hub genes showed negative correlations with tumor purity and positive correlations with infiltrating levels of immune filtrating cells. What’s more, we propose new treatment strategies for the two prognostic subtypes. Low- risk patients were found presenting with a higher level of immune checkpoint molecules and showing higher immunogenicity in immunophenoscore (IPS) analysis, which indicated a better response for immunotherapy. Meanwhile, estimated by Genomics of Drug Sensitivity in Cancer (GDSC) database, the high-risk patients showed sensitive responses to five chemotherapy drugs. Finally, 10 candidate small-molecule drugs for CESC were defined. In summary, the CD1C-CD6 signature can accurately predict the prognosis of CESC.  相似文献   
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BackgroundEffective improvement for the programmed death 1 (PD-1)/programmed death ligand 1 (PD-L1) inhibitors had been shown in advanced non-small cell lung cancer (NSCLC) patients compared with traditional therapy. However, we do not have ample evidences to demonstrate the safety and effectivity in the treatment of PD-L1-positive, advanced NSCLC. The relation was controversial about the expression of PD-L1 and survival outcomes of PD-1/PD-L1 inhibitors.Materials and methodsElectronic databases (PubMed, EMBASE, and the Cochrane library) and major conference proceedings were systematically searched for all clinical trials in NSCLC using PD-1/PD-L1 inhibitors. Randomized controlled trials (RCTs) were included to compare PD-1/PD-L1 inhibitors with chemotherapy in advanced NSCLC patients reporting adverse events (AEs) and immune-related AEs (irAEs). The incidence, Hazard Ratio (HR), Odds Ratio (OR), and corresponding 95% confidence interval (CI) of outcomes were calculated.ResultsA total of 4939 patients from 10RCTs were included. In the group of PD-L1 ≥ 1%, PD-L1 ≥ 5%, PD-L1 ≥ 10%, PD-L1 ≥ 50%, the HR of OS is 0.31(95%CI 0.38–0.23; p < 0.0001), 0.47(95%CI 0.82–0.12; p = 0.008), 0.85(95%CI 1.17–0.53; p < 0.0001), 0.47(95%CI 0.59–0.36; p < 0.0001) respectively. The HR of PFS is 0.13(95%CI 0.01–0.24; p = 0.027), 0.31(95%CI 0.00–0.62; p < 0.0001), 0.62(95%CI 0.30–0.93; p < 0.0001), 0.40(95% CI 0.20–0.59; p < 0.0001) respectively. In terms of summary adverse events, PD-1/PD-L1 inhibitors groups had a significant lower risks in any treat-realated AEs than chemotherapy. About irAEs, PD-1/PD-L1 inhibitors groups had a significant higher risks in irAEs than chemotherapy.ConclusionPD-1/PD-L1 inhibitors are generally effected and safer than chemotherapy for patients with PD-L1-positive, advanced NSCLC. However, PD-1/PD-L1 inhibitors can generate a unique spectrum of irAEs, and even life-threatening.  相似文献   
7.
Emotional difficulties have been observed in individuals with eating disorders across awide range of studies, including poor interoceptive awareness, confusion of emotional states and difficulties with emotional language. Literature has linked these difficulties with emotional functioning as being an important factor related to the core aetiology ofeating disorders, however limited knowledge exists to how this impacts on professionalability to engage patients within treatment as a result of such dysfunction. Using aqualitative design this paper explores how facets of Emotional intelligence (EI) are related to the experience of an eating disorder. The study sampled a total of 32 participants with either a professional background working with eating disorders (n=27)or participants with personal lived experience (n=5), with a number of the participants (n=13) identified as having dual roles. The findings of the study show that aspects of EIsuch as emotional regulation and lack of an emotional language are considered to beat the core of the onset and maintenance of these disorders. Additional aspects of emotional awareness and expression were found to be related to treatment disengagement and difficulties. Building on previous literature, this paper found suchemotional deficits as a transdiagnostic issue rather than specifically anorexia nervosa. Furthermore, such dysfunction was seen by professionals to have a considerable impact on therapeutic relationships and successful treatment. These findings provide insight into the potential applications that EI may have in addressing aspects of theeating disorder to create better outcomes for treatment and intervention models.  相似文献   
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《中国现代医生》2020,58(29):24-27+封三
目的 探讨肝癌组织中LncRNA TINCR 表达水平对术后长期生存的影响。方法 回顾性分析2013 年4 月~2016 年2 月间在本院接受手术治疗的157 例肝细胞肝癌患者的临床资料。RT-PCR 法检测肝癌标本内LncRNA TINCR 表达水平,采用ROC 曲线和Kaplan-Meier 法分析LncRNA TINCR 表达水平对肝癌术后长期生存的影响。结果 肝癌组织LncRNA TINCR 表达水平对术后长期生存预测的曲线下面积(AUC)为0.812,特异度为73.77%,灵敏度为79.17%,最佳判读值为1.89(P<0.0001)。根据ROC 曲线分析结果,将肝癌组织LncRNA TINCR 相对表达水平大于1.89 的93 例(59.24%)患者纳入高表达组,而肝癌组织LncRNA TINCR 相对表达水平小于或等于1.89的64 例(40.76%)患者纳入低表达组。Kaplan-Meier 法生存分析发现高表达组术后3 年内有76 例患者死亡,3 年总生存率为18.28%(17/93);低表达组术后3 年内有20 例患者死亡,3 年总生存率为68.75%(44/64),低表达组3 年总生存率明显优于高表达组(P<0.0001,两组间死亡风险比为3.7534,95%可信区间为2.5158~5.6000)。结论 肝癌组织LncRNA TINCR 表达水平与肝癌术后长期生存显著相关,LncRNA TINCR 表达水平升高则预示着预后不佳。  相似文献   
10.
Cadmium (Cd) is a ubiquitous environmental contaminant implicated as a developmental toxicant, yet the underlying mechanisms that confer this toxicity are unknown. Mother-infant pairs from a Rhode Island birth cohort were investigated for the potential effects of maternal Cd exposure on fetal growth, and the possible role of the PCDHAC1 gene on this association. Mothers with higher toenail Cd concentrations were at increased odds of giving birth to an infant that was small for gestational age or with a decreased head circumference. These associations were strongest amongst those with low levels of DNA methylation in the promoter region of placental PCDHAC1. Further, we found placental PCDHAC1 expression to be inversely associated with maternal Cd, and PCDHAC1 expression positively associated with fetal growth. Our findings suggest that maternal Cd affects fetal growth even at very low concentrations, and some of these effects may be due to the differential expression of PCDHAC1.  相似文献   
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