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1.
肥厚型心肌病(HCM)是一种常见的遗传性心脏病,是青少年及年轻运动员心源性猝死的最主要原因之一,其分子遗传学基础为基因突变。TNNC1是HCM的重要致病基因之一,目前仅发现其少量非同义单核苷酸多态性(nsSNPs)位点与HCM发病相关,但该基因其他nsSNPs数量较多,结合临床进行实验遗传检测其基因型与表型的关系,工作量巨大,尚不可行。因此,采用生物信息学方法,从dbSNP数据库中筛选出TNNC1基因全部的nsSNPs,联合4款(Mutation Taster、PolyPhen-2、PhD-SNP和MutPred)专业软件,进行有害性分级筛选和致病关联预测,最后进行突变蛋白三维结构建模及可视化分析。结果显示,首次从TNNC1基因102个nsSNPs位点中预测出疾病相关的18个(G159D、S69R、P52R、D149G、D3V、G140E、N51K、D151V、M47R、G110C、A23D、G140R、K158N、C35Y、R147C、L48P、F74C和V44G)高风险nsSNPs。基于生物信息学方法,以TNNC1基因的nsSNPs为示范,分析其nsSNPs与疾病表型的关系,这为其他遗传疾病致病基因nsSNPs的关联分析打下理论研究基础,具有重要的参考价值。  相似文献   
2.
BackgroundThe growing enthusiasm for the use of reverse shoulder arthroplasty (RSA) in the treatment of primary glenohumeral osteoarthritis (GHOA) with an intact rotator cuff is based on data derived from single-center studies with limited generalizability and follow-up. This study compared patient-reported outcomes (PROs) between RSA and total shoulder arthroplasty (TSA) for the treatment of primary GHOA with up to 5-year follow-up and examined temporal trends in the treatment of GHOA between 2012 and 2021.MethodsA retrospective review was performed on patients with primary GHOA undergoing primary arthroplasty surgery from the Surgical Outcomes System global registry between 2012 and 2021. PROs including the American Shoulder and Elbow Surgeons (ASES) score, Single Assessment Numeric Evaluation (SANE) score, and visual analog scale (VAS) for pain were compared between RSA and TSA at 1, 2, and 5 years postoperatively.ResultsA total of 4451 patients were included, with 2693 (60.5%) undergoing TSA and 1758 (39.5%) undergoing RSA. Both RSA and TSA provided clinically excellent outcomes at 1 year postoperatively (ASES: 80.8 ± 17.9 vs. 85.9 ± 15.2, respectively; SANE: 74.8 ± 24.7 vs. 79.5 ± 22.9; VAS pain: 1.3 ± 2.0 vs. 1.1 ± 1.7; all P < .05) that were maintained at 2 years (ASES: 81.3 ± 19.3 vs. 87.3 ± 14.9; SANE: 74.8 ± 26.2 vs. 79.7 ± 24.7; VAS pain: 1.3 ± 2.1 vs. 1.0 ± 1.6; all P < .05) and 5 years (ASES: 81.7 ± 16.5 vs. 86.9 ± 15.3; SANE: 71.6 ± 28.5 vs. 78.2 ± 25.9; VAS pain: 1.0 ± 1.7 vs. 1.0 ± 1.7; all P < .05), with statistical significance favoring TSA. After controlling for age and sex, there was an adjusted difference of 4.5 units in the ASES score favoring TSA (P = .005) at 5 years postoperatively but no differences in adjusted SANE (P = .745) and VAS pain (P = .332) scores. The use of RSA for GHOA grew considerably over time, from representing only 17% of all replacements performed for GHOA in 2012 to nearly half (47%) in 2021 (P < .001).ConclusionRSA as a treatment for GHOA with an intact rotator cuff seems to yield PROs that are largely clinically equivalent to TSA extending to 5 years postoperatively. The observed statistical significance favoring TSA appears to be of marginal clinical benefit based on established minimal clinically important differences and may be a result of the large sample size. Further research using more granular clinical data and examining differences in range of motion and complications is warranted as it may change the value analysis.  相似文献   
3.
4.
《Indian heart journal》2022,74(4):302-306
BackgroundThe alarming rise in prevalence of hypertension warrants psychosocial methods supplementing pharmacotherapy for better management and prevention of cardiac emergencies. The objective of the study was to assess the differential impact of the form and frequency of knowledge intervention on management of primary hypertension.Materials and methodThe study was conducted on 256 hypertensive patients recruited through purposive sampling at health centers in Hyderabad, India. Pretest post-test control group quasi-experimental design was adopted for the study. There were two forms of the knowledge intervention, namely ‘Direct Interaction’ and ‘Audio-Visual’. Each form was presented in two frequencies namely ‘single exposure’ and ‘double exposure’. The four groups were labelled as Direct Intervention Single (DIS), Direct Intervention Double (DID), Audio-Visual Single (AVS) and Audio-Visual Double (AVD). Adherence and management of hypertension were assessed at baseline and six weeks post experiment. Analysis of Covariance (ANCOVA) was applied using IBM SPSS Statistics version 20.ResultsANCOVA followed by Bonferroni Multiple Group Comparison Test revealed significant differences between the four intervention groups and control group on adherence (p< .001). In case of hypertension management significant differences were observed between Control group and DIS, DID (p < .001), Control and AVS (p < .01). Control group did not differ from AVD.ConclusionThere was a positive impact of Knowledge Intervention on adherence and management of hypertension. Double exposure in audio visual form was counterproductive in hypertension management.  相似文献   
5.
目的评估猪尾巴导管在单孔胸腔镜肺肿瘤手术中应用的有效性。方法回顾性分析2020年1月至12月上海交通大学医学院附属仁济医院东院接受单孔胸腔镜肺肿瘤手术的患者共441例,根据是否放置猪尾巴导管分为胸管组和猪尾巴管组,通过倾向性评分匹配法进行1∶1匹配,对比两组患者围手术期的各项指标。结果匹配后每组143例配对成功,匹配后两组间基线特征无统计学差异。对比两组围手术期指标发现,猪尾巴管组患者术后3天胸腔引流总量显著多于胸管组(375.49 ml对285.03 ml,P<0.001),术后两周复查CT示胸腔积液量显著少于胸管组(131.77 ml对178.84 ml,P=0.032),两组术后疼痛评分、引流天数及住院天数无明显统计学差异。结论加放猪尾巴导管可有效改善单孔胸腔镜肺肿瘤术后胸腔引流情况,且不增加患者术后疼痛,不延长胸腔引流及住院天数。  相似文献   
6.
姚刚  曹新岭  李涛 《中国全科医学》2022,25(12):1429-1434
背景 既往对肝癌微血管侵犯病理诊断的重要性重视不够,目前国内外缺乏对微血管侵犯统一的病理诊断标准,也未将微血管侵犯列为病理常规诊断指标。C反应蛋白/白蛋白比值(CAR)作为新型系统性炎性因子,与肝癌的增殖、侵袭转移等恶性生物学行为密切相关。 目的 探讨CAR预测单发小肝癌患者微血管侵犯的价值。 方法 选择2017年6月至2021年6月在新疆医科大学第一附属医院行肝切除术的单个、肿瘤直径≤5 cm的术后病理检查证实为肝癌的患者346例为研究对象。收集患者一般资料,并计算CAR。绘制CAR预测单发小肝癌患者微血管侵犯的受试者工作特征(ROC)曲线,并计算CAR的最佳诊断截点,根据CAR最佳诊断截点将患者进行分组,采用1∶1最近邻居倾向性评分匹配(PSM)法将Logistic模型估计的倾向性评分相近患者进行配对,得到两组间各临床特征比较均衡性较高的样本。比较匹配后两组患者微血管侵犯率,采用Logistic回归分析评估匹配前、后CAR对单发小肝癌患者微血管侵犯的预测价值。 结果 346例患者中微血管侵犯阳性131例(37.9%),微血管侵犯阴性215例(62.1%)。ROC曲线分析结果显示,CAR预测单发小肝癌患者微血管侵犯的灵敏度为82.9%,特异度为76.4%,ROC曲线下面积为0.787〔95%CI(0.697,0.877)〕,最佳诊断截点为0.03。根据CAR最佳诊断截点,将患者分为CAR<0.03组(A组,n=145)和CAR≥0.03组(B组,n=201)。采用1∶1最近邻居PSM法,共92对匹配成功,匹配后两组临床资料均衡。匹配后,B组患者微血管侵犯发生率〔43.5%(40/92)〕高于A组〔13.0%(12/92)〕(χ2=6.314,P=0.013)。采用3种Logistic回归分析结果显示,匹配前、后CAR均为单发小肝癌患者微血管侵犯的独立影响因素(P<0.05)。 结论 CAR作为新型系统性炎症指标,可用于预测单发小肝癌微血管侵犯,当CAR≥0.03时提示单发小肝癌微血管侵犯发生率较高。  相似文献   
7.
Iron is bound to mobile transferrin (TF) and ferritin in blood. TF receptors (TFRC and TFR2) regulate intracellular iron by delivering iron from TF into the cytoplasm. In this study, we examined the effects of 10 single nucleotide polymorphisms (SNPs) in each of the genes for TF and TF receptors on blood iron concentrations in Japanese subjects. Blood iron levels were determined by microwave plasma-atomic emission spectrometry and the SNPs were analyzed by polymerase chain reaction followed by restriction fragment length polymorphism analysis. Blood iron levels in males were significantly higher than those in females. Therefore, the analysis was performed only in males. Blood iron concentrations did not correlate with age and postmortem intervals in males. Among the 10 SNPs in TF, TFRC, and TFR2 genes, significant associations were observed between TF genotypes (rs12769) and male iron concentrations. Individuals with genotype GG in rs12769 had significantly higher blood iron concentrations than those with GA. Previous studies have shown the association between high tissue iron concentrations and disease, liver iron levels are higher in infants dying from sudden infant death syndrome and decreased blood iron concentrations were observed in critically ill children. Therefore, rs12769 in TF might be related to diseases and mortality risk.  相似文献   
8.
We present a case with discordant results in three prenatal screening methods, with additional genetic analyses. Non-invasive prenatal testing (NIPT) was performed on a 41-year-old Japanese woman at 10 weeks of gestation, and the result was positive for trisomy 18 with high accuracy. Amniocentesis was performed at 16 weeks of gestation. However, the result showed 47,XX,+mar[16]/47,XX,+18[2]. Fetal examination by ultrasound revealed no malformations. After termination of the pregnancy, we performed additional genetic analyses, and confirmed the presence of confined placental mosaicism (CPM). Furthermore, a small supernumerary marker chromosome (sSMC) was detected in fetal cells, which was derived de novo from the centromere of chromosome 18. Single nucleotide polymorphism array analysis revealed that fetal chromosome 18 was inherited with maternal uniparental disomy, with a relatively large copy-neutral loss of heterozygosity, including its centromere. Our genetic analyses strongly indicated the cause of result discrepancy in prenatal testing as incomplete trisomy 18 rescue leading to atypical CPM with a sSMC. These findings also offer insight into the mechanisms by which chromosomal aberrations form during human oogenesis and embryogenesis.  相似文献   
9.

Background

Glucocorticoids play essential roles in the treatment of childhood acute lymphoblastic leukaemia (ALL); however, treatment with these agents can result in severe side-effects. This study, the first of its kind in a Saudi population, investigates associations of ABCB1 gene polymorphisms (pharmacodynamics and pharmacokinetic) with the development of toxicity and side effects (glucose abnormality, liver toxicity and infection) in a small population of Saudi children with ALL.

Methods

Three single nucleotide polymorphisms (SNPs) of the ABCB1 gene (rs 3213619 T129C, rs 2032582 G2677T and rs1045642 C3435T) were analysed in 70 Saudi children with ALL and 60 control subjects. Participants were treated according to the ALL 2000 study protocol. Toxicities were assessed and associations with genotypes were evaluated according to Common Toxicity Criteria (NCI-CTC).

Results

Significant associations were observed among carriers and the mutated genotype C3435T (ABCB1), which had an incidence of infection (p?=?0.05). Although no correlations were found between liver toxicity and glucose abnormalities for patients carrying ABCB1 SNPs, risk factors for liver toxicity were elevated by a factor of three for patients carrying the SNP G2677T, OR 3.00 (1.034–8.702). The risk factor of glucose abnormality toxicity for the patients carring T129C were increased three times OR 3.06 (0.486–19.198).

Conclusions

In terms of infection incidence, polymorphism C3435T may contribute to potential life-threatening infections during paediatric ALL therapy, through glucocorticoid usage.  相似文献   
10.
Chronic progressive external ophthalmoplegia (CPEO) is a frequent clinical manifestation of disorders caused by pathogenic mitochondrial DNA mutations. However, for diagnostic purposes skeletal muscle tissue is used, since extraocular muscle tissue is usually not available for work-up. In the present study we aimed to identify causative factors that are responsible for extraocular muscle to be primarily affected in CPEO. We performed comparative histochemical and molecular genetic analyses of extraocular muscle and skeletal muscle single fibers in a case of isolated CPEO caused by the heteroplasmic m.5667G>A mutation in the mitochondrial tRNAAsn gene (MT-TN). Histochemical analyses revealed higher proportion of cytochrome c oxidase deficient fibers in extraocular muscle (41%) compared to skeletal muscle (10%). However, genetic analyses of single fibers revealed no significant difference either in the mutation loads between extraocular muscle and skeletal muscle cytochrome c oxidase deficient single fibers (extraocular muscle 86% ± 4.6%; skeletal muscle 87.8 %± 5.7%, p = 0.246) nor in the mutation threshold (extraocular muscle 74% ± 3%; skeletal muscle 74% ± 4%). We hypothesize that higher proportion of cytochrome c oxidase deficient fibers in extraocular muscle compared to skeletal muscle might be due to facilitated segregation of the m.5667G>A mutation into extraocular muscle, which may explain the preferential ocular manifestation and clinically isolated CPEO.  相似文献   
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