基于多重PCR技术检测蜡样芽胞杆菌3种毒素基因方法的建立及评价

目的 基于多重PCR技术,建立一种快速检测蜡样芽胞杆菌nhe、cytK和entFM 3种毒素基因的方法,并评价其效能。 方法 煮沸法提取蜡样芽胞杆菌DNA,以蜡样芽胞杆菌nhe、cytK和entFM特异性毒素基因作为靶基因,采用NCBI primer-BLAST 5.0软件设计特异性引物,优化反应体系。建立三重PCR检测体系,并检测其特异性、灵敏度和稳定性。 结果 煮沸法提取蜡样芽胞杆菌DNA,浓度为227 mg·L^－1,纯度为1.50~1.60。采用多重PCR体系同时检测蜡样芽胞杆菌3种毒素致病基因,于退火温度56 ℃时,蜡样芽胞杆菌基因引物nhe499的扩增片段为499 bp,基因引物cytK191的扩增片段为191 bp,基因引物entFM363的扩增片段为363 bp。PCR体系扩增蜡样芽胞杆菌3种毒素基因后条带清晰明亮,且无非特异性条带,与金黄色葡萄球菌、大肠埃希菌和铜绿假单胞菌均无扩增,表明蜡样芽胞杆菌基因引物nhe499、cytK191和entFM363特异性强;3种引物在同一反应体系中互不干扰。灵敏度检测,多重PCR体系最低检测限可同时达到10^－1 mg·L^－1;稳定性检测,多重PCR体系自制备起每6个月检测稳定性一致。 结论 建立的多重PCR检测体系对于蜡样芽胞杆菌nhe499、cytK191和entFM363 3种毒素基因灵敏度高、特异性强,检测结果准确稳定,检测体系具有良好稳定性,适用于快速检出蜡样芽胞杆菌的3种不同致病毒素基因。     

Timing of surgery for asymptomatic patients with severe aortic valve stenosis: An updated systematic review and meta-analysis

BackgroundThe research findings concerning the effect of early surgery on mortality among asymptomatic patients with severe aortic valve stenosis (AS) are controversial and contradictory. In this study, the total weight of evidence regarding early surgery versus conservative management in these population was examined.MethodsEmbase, PubMed, CENTRAL, and CINAHL databases were thoroughly searched without language restriction until 29 February, 2020. We included all studies exploring the mortality in asymptomatic patients with severe AS comparing early surgery with conservative management and obtained data in a standard form. Pooled relative risks ratios (RRs) and 95% confidence intervals (CI) were pooled by using a random- or fixed-effects model and by using intention-to-treat principle. Randomized controlled trials (RCTs) and observational studies (OSs) were analyzed separately.ResultsFinally, 8 studies involving 2462 patients were enrolled, including 1 RCT and 7 OSs. In the OSs, early surgery was linked with significant reduction among all-cause mortality (RR & 95% CI, I²: 0.32 (0.18-0.57), 84.9%) and cardiac death (0.28 (0.18–0.45), 62.5%) in asymptomatic patients with severe AS. The superiority of early surgery over conservative management in reducing all-cause mortality in these patients is also intensified in the RCT.ConclusionsThe existing RCT and OSs indicate that earlier surgery is associated with better outcomes for asymptomatic patients with severe AS. Nevertheless, more well-designed and large-sized RCTs are needed to find an individual approach focusing on individual risk stratification and staging.     

腹股沟疝修补术不同解剖入路疗效的Meta分析

目的比较经腹腔腹膜前(TAPP)和经完全腹膜外(TEP)疝修补术的优势。方法收集2005年1月~2014年8月已发表的关于TAPP和TEP疝修补术的国内外文献,针对结果进行统计分析。采用标准化均数差(SMD)或优势比(OR)及95%可信区间(95%CI)描述效应量。结果共7篇文献符合标准纳入,包括1373例(TAPP组)和3689例(TEP组)进行分析。两组的手术时间比较,差异有统计学意义(P<0.01)(SMD为0.33,95%CI为0.13~0.54);两组的术后镇痛时间比较,差异有统计学意义(P<0.01)(SMD为0.55,95%CI为0.28~0.82);两组的术后并发症发生率比较,差异无统计学意义(P>0.05)(OR为0.66,95%CI为0.42~1.02);两组的术后复发率比较,差异无统计学意义(P>0.05)(OR为1.10,95%CI为0.36~3.37)。结论 TAPP疝修补术具有节省时间、痛苦小的优点,与TEP疝修补术相比,具有一定优势。     

ST6型金黄色葡萄球菌食物中毒菌株的毒力因子分析

目的检测食物中毒优势型ST6型菌株的毒力基因特征,为食品安全风险评估、食源性病原菌的监测和致病性研究提供依据。方法选取深圳地区7次食物中毒收集的32株ST6型菌株进行全基因组测序,利用VFDB数据库进行毒力因子分析,并通过序列比对进行SEA亚型分析。结果第1-4起食物中毒ST6菌株携带的毒力因子谱完全相同;第5-7起食物中毒中,同一起食物中毒的暴发菌株携带的毒力因子一致,而非暴发菌株与暴发菌株携带的毒力因子不完全一致。在32株ST6型菌中,与粘附、酶和Ⅶ型分泌系统相关的毒力基因具有较高的携带率,α-溶血素(hly/hla)、β-溶血素(hlb)、δ-溶血素(hld)、γ-溶血素基因(hlgA、hlgB、hlgC)、肠毒素A基因(sea)和表皮剥脱毒素A基因(eta)的携带率均为100%,双组分白细胞毒素LukDE基因(lukD和lukE)的携带率为96.8%。所有菌株携带的肠毒素A均为SEA1亚型。结论32株ST6型食物中毒相关菌株携带多个毒力因子基因,以cna、sea、eta、lukD、lukE毒力基因携带率较高,编码的毒力因子可能对ST6型菌株的致病性产生影响。     

Estimating the Economic Burden of Acute Myocardial Infarction in the US: 12 Year National Data

BackgroundAcute myocardial infarction (AMI) carries a substantial mortality and morbidity burden. The purpose of this study is to provide annual mean cost per patient and national level estimates of direct and indirect costs (lost productivity from morbidity and premature mortality) associated with AMI.MethodsNationally representative data spanning 12 years (2003-2014) with a sample of 324,869 patients with AMI from the Medical Expenditure Panel Survey (MEPS) were analyzed. A novel 2-part model was used to examine the excess direct cost associated with AMI, controlling for covariates. To estimate lost productivity from morbidity, an adjusted Generalized Linear Model was used for the differential in wage earnings between participants with and without AMI. Lost productivity from premature mortality was estimated based on published data.ResultsThe total annual cost of AMI in 2016 dollars was estimated to be $84.9 billion, including $29.8 billion in excess direct medical expenditures, $14.6 billion in lost productivity from morbidity and $40.5 billion in lost productivity from premature mortality between 2003 and 2014. In the adjusted regression, the overall excess direct medical expenditure of AMI was $7,076 (95% confidence interval [CI] $6,028-$8,125) higher than those without AMI. After adjustment, annual wages for patients with AMI were $10,166 (95% CI −$12,985 to −$7,347) lower and annual missed work days were 5.9 days (95% CI 3.57-8.27) higher than those without AMI.ConclusionsThe study finds that the economic burden of AMI is substantial, for which effective prevention could result in significant health and productivity cost savings.     

WASF3 Knockdown Sensitizes Gastric Cancer Cells to Oxaliplatin by Inhibiting ATG12-Mediated Autophagy

BackgroundGastric cancer is one of the most aggressive tumors, usually resulting in metastasis, and therapies for advanced gastric cancer remain limited. Drug resistance is the main reason for chemotherapeutic failure in gastric cancer. Wiskott-Aldrich syndrome protein family member 3 (WASF3) is required for invasion and metastasis of different cancers. However, there has been little study of WASF3 expression involvement in gastric cancer. In this study, we explored the role of WASF3 in the sensitivity of gastric cancer to oxaliplatin, and the underlying mechanisms.MethodsWe silenced WASF3 using WASF3-siRNA in MGC803 cells. Then, CCK-8, flow cytometry and transwell assay were performed to study the effect of WASF3 silencing on proliferation, migration, invasiveness and apoptosis of MGC803 cells. Moreover, we evaluated the potential mechanism in vitro to determine the sensitization to oxaliplatin induced by WASF3.ResultsWASF3 silencing by small interfering RNA inhibited the proliferation, migration and invasiveness of gastric cancer cells. We also observed that WASF3 knockdown promoted cell apoptosis and enhanced oxaliplatin sensitivity. Furthermore, the sensitization to oxaliplatin induced by WASF3 knockdown depended on the inhibition of Atg12-mediated autophagy.ConclusionsOur analysis demonstrates WASF3 targeting is a new potential therapeutic strategy for gastric cancer.     

Novel chemical permeation enhancers for transdermal drug delivery

Transdermal drug delivery has been accepted as a potential non-invasive route of drug administration, with advantages of prolonged therapeutic action, decreased side effect, easy use and better patient compliance. However, development of transdermal products is primarily hindered by the low permeability of the skin. To overcome this barrier effect, numerous new chemicals have been synthesized as potential permeation enhancers for transdermal drug delivery. In this review, we presented an overview of the investigations in this field, and further implications on selection or design of suitable permeation enhancers for transdermal drug delivery were also discussed.     

Assessment of RANTES levels as the indicators of plaque vulnerability in rabbit models of atherosclerosis

The aim of the present study was to determine the chemokine RANTES (regulated on activation, normal T-cell expressed, and secreted) levels in plasma and atherosclerotic plaques and to assess their diagnostic efficacy in the evaluation of vulnerable plaques. The rabbit models of vulnerable atherosclerotic plaque (VAP) were established by high fat diet and pharmaceutical triggering. The serum RANTES levels of VAP group (91.97 ± 8.51 ng/ml) were significantly higher than those of AS (atherosclerosis) group (50.03 ± 2.92 ng/ml). Consistently, the mRNA and protein of RANTES in vulnerable atherosclerotic plaques were also obviously up-regulated compared to AS group (P < 0.01). Moreover, corrected plaque area and vulnerability index of VAP group proved to be significantly higher than AS group. The correlation coefficient between RANTES and plaque vulnerability indicated that RANTES, especially plaque RANTES, was positively correlated with VAP. In addition, increased expression of nuclear factor kappa B p65 (NF-κB p65) was observed in VAP group compared to AS group (P < 0.05), which partly accounted for the increased RANTES levels. In conclusion, positive associations between RANTES and plaque vulnerability suggest that higher RANTES levels may be associated with atherosclerosis and high-risk plaques. Our study highlights the utility of both serum and plaque RANTES levels as indicators of plaque vulnerability in the field of preventive cardiology.     

Ex vivo intra-arterial methylene blue injection in the operation theater may improve the detection of lymph node metastases in colorectal cancer

IntroductionLymph node (LN) assessment after colorectal cancer resection is fundamentally important for therapeutic and prognostic reasons. LN positivity is an indication for adjuvant treatment. This study aimed to investigate whether immediate postoperative intra-arterial methylene blue (MB) injection (MBI) into colorectal cancer specimens by a surgeon in the operating room could improve the rate of total LN and metastatic LN recovery for pathological examination.Materials and methodsSeventy-three consecutive patients prospectively enrolled between January 2011 and December 2013 were assigned to the methylene blue (MB)-stained group and compared with 107 controls in the unstained group.ResultsThe median number and range values of metastatic LNs, the number of LNs <0.5 cm, the total number of LNs harvested, and the number of cases with LN metastasis were significantly different between the MB-stained and MB-unstained groups (p = 0.016, p = 0.010, p = 0.025, and p = 0.006 respectively).ConclusionsImmediate MBI (fresh, unfixed samples) by a surgeon in the operating room may result in a significant increase in the number of metastatic LNs diagnosed and the number of cases with positive LNs. Shifting of the injection from the pathology laboratory to the operation theater would be a good alternative whenever the operation theater is not the area located as the pathology department.