表没食子儿茶素没食子酸酯联合叶酸杀伤胃癌细胞的实验研究

背景：表没食子儿茶素没食子酸酯（EGCG）具有抗肿瘤作用，对不同胃肠道肿瘤细胞系具有不同程度的、呈剂量依赖的杀伤作用。叶酸是一种水溶性维生素，叶酸缺乏可增加肿瘤的发生率，影响肿瘤细胞凋亡。目的：研究EGCG联合叶酸对胃癌细胞杀伤作用的影响。方法：以甲基噻唑基四唑（MTT）比色法检测EGCG联合叶酸对胃癌细胞系MKN45、SGC7901、MKN28的杀伤作用。流式细胞仪测定两者对MKN45细胞周期的影响。结果：EGCG联合叶酸较EGCG单独作用对MKN45、SGC7901、MKN28细胞的杀伤作用增强，EGCG半数抑制浓度（IC50）分别降低28．4％、51．9％和40．0％。3种浓度的EGCG联合叶酸作用48h后，MKN45细胞的细胞周期分布与对照组和EGCG组相比无明显变化（P〉0．05）。结论：EGCG联合叶酸较EGCG单独作用对胃癌细胞的杀伤作用增强，但对MKN45的细胞周期分布无明显影响。     

Two dimensional echocardiography in mitral, aortic and tricuspid valve prolapse: The clinical problem, cardiac nuclear imaging considerations and a proposed standard for diagnosis

The mitral valve prolapse syndrome may present with a variety of clinical manifestations and has proved to be a common cause of nonspecific cardiac symptoms in clinical practice. Primary and secondary forms must be distinguished. Myxomatous degeneration appears to be the common denominator of the primary form. The diagnostic standard of this form has not previously been defined because the detection of mitral leaflet tissue in the left atrium (prolapse) on physical examination or angiography is nonspecific. M mode echocardiography has greatly enhanced the recognition of this syndrome but has not proved to be the best diagnostic standard because of its limited view of mitral valve motion. The advent of two dimensional echocardiography has provided the potential means for specific identification of the mitral leaflet motion in systole and can be considered the diagnostic standard for this syndrome. Primary myxomatous degeneration with leaflet prolapse is not localized to the mitral valve. Two dimensional echocardiography has detected in preliminary studies tricuspid valve prolapse in up to 50 percent and aortic valve prolapse in about 20 percent of patients with idiopathic mitral valve prolapse.     

黄芩甙对HBsAg和HBeAg的体外抑制作用

目的：观察黄芩甙(Baicalin,Bai)对2．2．15细胞分泌HBsAg和HBeAg的影响，探讨黄芩甙的体外抗HBV作用。方法：通过四甲基偶氮唑盐(MTT)法观察黄芩甙对2．2．15细胞的影响，采用ELlSA法检测分析黄芩甙对2．2．15细胞分泌m6Ag、HBeAg的抑制作用。结果：黄芩甙在2．2．15细胞上半数毒性浓度大于15mg／ml，在该浓度下对HBsAg、HBeAg的抑制率分别达100％、88％以上，在黄芩甙浓度为0．94～15mg／ml时，对2．2．15细胞分泌HBsAg、HBeAg的抑制率高于70％，治疗指数分别为65．22和21．74。结论：黄芩甙有显著的体外抑制HBV作用，属低毒有效药物，具有潜在的抗HBV开发前景。     

A novel SARS-CoV-2 IgG line-blot for evaluating discrepant IgG test results – Observations in pre-pandemic and follow-up samples of five patients

To confirm discrepant SARS-CoV-2-IgG results in four standard assays we applied for the first time a prototype of a coronavirus IgG-line-blot which employs antigens from seasonal coronaviruses, SARS-1 and SARS-CoV-2 combined with avidity testing as a confirmatory tool in a follow-up of five cases including pre-pandemic samples.     

Incidence,severity and outcome of central line related complications in pediatric oncology patients; A single center study

BackgroundCentral venous access device (CVAD)-related complications are associated with high morbidity rates. This study was performed to underline the importance of CVAD-complication prevention and treatment.MethodsAn audit of practice of CVAD-related complications in pediatric oncology patients receiving a CVAD between January 2015 and June 2017 was performed. CVADs included were totally implantable venous access ports (TIVAPs), Hickman–Broviac® (HB), nontunneled, and peripherally inserted CVADs.ResultsA total of 201 children, with 307 CVADs, were analyzed. The incidence rates per 1000 CVAD-days for the most common complications were 1.66 for malfunctions, and 1.51 for central line-associated bloodstream infections (CLABSIs). Of all CVADs inserted, 37.1% were removed owing to complications, of which 45.6% were owing to CLABSIs. In 42% of the CLABSIs, the CLABSI could be successfully cured with systemic antibiotic treatment only. Of all included patients, 5.0% were admitted to the intensive care unit owing to CLABSI. The HB-CVAD compared to the TIVAP was a risk factor for CVAD-related complications, CLABSIs and dislocations in particular.ConclusionsThe incidence of CVAD-related complications is high. Research on the prevention and treatment of CVAD-related complications in pediatric oncology patients should be a high priority for all health care professionals.Type of studyPrognosis study (retrospective).Level of evidenceLevel II.     

Solid state line scan cameras for measuring strain in soft tissues and implants

The line scan camera, or LSC, is an inexpensive and easily applied technique for optical strain measurement of soft biomaterials. The LSC is based on a linear array of photodiodes; in gauging applications, where measurements between dark/light interfaces are important, the digital nature of the array can be exploited. Advantages of the LSC include low cost, high frequency response, applicability to front- or backlighted samples, insensitivity to stray and nonuniform lighting as well as to accidental overexposure, ease and linearity of calibration, and lack of temperature sensitivity. With the 1024 element arrays used herein, the relative resolution is theoretically limited to 1 part in 1024, or 0.1%; in practice, the relative resolution is somewhat poorer. LSCs have been successfully used in mechanical tests to measure the diameter of arteries and compliant vascular grafts, the longitudinal strain of vascular grafts, and the dynamic diameter of elastic tube models of graft/artery systems in pulsatile flow visualization experiments.