Advances in preimplantation genetic diagnosis/screening

Preimplantation genetic diagnosis (PGD) gives couples who have a high risk of transmitting genetic disorders to their baby the chance to have a healthy offspring through embryo genetic analysis and selection. Preimplantation genetic screening (PGS) is an effective method to select euploid embryos that may prevent repeated implantation failure or miscarriage. However, how and to whom PGS should be provided is a controversial topic. The first successful case of PGD of a human being was reported in 1990, and there have been tremendous improvements in this technology since then. Both embryo biopsy and genetic technologies have been improved dramatically, which increase the accuracy and expand the indications of PGD/PGS.     

单克隆抗体药物风雨飘摇20年

1986年,美国FDA批准了第一个单克隆抗体药物上市.迄今,全世界共有21个治疗用抗体药物被批准上市,实现300亿美元的销售额,促进了国际、国内抗体药物的开发热潮.巨大的市场前景和亟待克服的技术问题及壁垒并存的现实不可避免地引发抗体药物的新一轮技术革命,而其结果又将毫无疑问地改变抗体药物的市场格局.抗体药物的研究和开发能否真正成为中国生物技术药物开启国际市场大门的新钥匙？何为我们首选的切入点？我们又该如何形成自己的特色和竞争优势？回顾国际抗体药物20年风雨飘摇的发展经历,总结其中的经验教训,无疑会给我们一些有益的启示.     

青石斑鱼MHCclassI基因的克隆与分析

目的克隆青石斑鱼MHCclassI基因,为研究石斑鱼的免疫系统和MHCclassI基因库提供材料。方法首先利用MHCclassI基因的特征,根据已知MHCclassI基因及其特点设计简并引物得到MHCclassI部分序列,然后分别利用5′RACE、3′RACE延伸至全基因的两端。将得到的序列拼接,经NCBI上BLASTx分析青石斑鱼MHCclassI基因核心区域,设计引物得到青石斑鱼MHCclassI基因。最后,将所得MHCclassI基因所对应氨基酸与几种鱼和人类MHCclass分子利用DNAMAN和MEGA软件分别进行比对和绘制分子进化树。结果成功得到青石斑鱼5个MHCclassI基因和绘制了MHCclassI分子进化树。同源性分析发现5个MHCclassI基因氨基酸同源性85.69%即高度的多变性。经氨基酸序列分析,青石斑鱼与已知鱼类和人MHCclassI基因的氨基酸序列存在30.27%～73.46%同源性其中不同鱼类同源性比对的比值表现为不同种类的鱼亲缘关系越近同源性比值越高。结论青石斑鱼MHCclassI基因具有已知物种MHCclassI基因特征。MHCclassI分子可以为生物进化分析提供依据。     

用FISH技术研究人类体外未受精卵的21号染色体非整倍体

采用荧光原位杂交技术,选用人类21号染色体端粒探针（21qter）,检测人类体外未受精卵的21号染色体非整倍体发生率,并比较非整倍体率与25－30岁和31－35岁这两个女性年龄组、IVF指征、超排方案之间的关系,在54个未受精卵中,正常21号单体30枚,二体16枚,三体4枚,缺体4枚,非整倍体率为44.4％（24／54）;25－30岁和31－35岁这两个年龄组、IVF指征、超排方案的患者的21号染色体非整倍体率之间的差异无显著性,卵母细胞21号染色体的非整倍性是造成体外受精失败的重要原因之一。     

Childhood Hygienic Practice and Family Education Status Determine the Prevalence of Helicobacter pylori Infection in Iran

Background: Management of Helicobacter pylori , a causative agent of gastrointestinal diseases is an important health problem in most countries. The main reasons include poorly defined epidemiological status and unrecognized mode of bacterial transmission. Our objective was to investigate the prevalence of H. pylori infection in a representative population of Iran and to evaluate possible risk factors for the H. pylori infection.
Materials and methods: In this cross-sectional study, 2561 healthy individuals aged 18–65 years (mean age, 35.5 years) were selected out of 12,100,000 inhabitants of Tehran province by cluster sampling. Infection with H. pylori was evaluated by detection of anti- H. pylori IgG antibody in serum. Sociodemographic status of each subject was determined by filling up a questionnaire.
Results: Prevalence of H. pylori infection was 69% and was correlated with increasing age. The highest infection rate (79.2%) was seen in individuals 46–55 years old. No association was detected between H. pylori positivity and gender. Low education of the study subjects; low father's and mother's education; poor tooth brushing habit; crowded families in childhood; and lack of household bath, hygienic drinking water, and swage disposal facility in childhood were determined as possible risk factors.
Conclusions: The rate of prevalence of H. pylori infection was higher than developed countries. Low socioeconomic status, poor sanitary indications, and crowded families in childhood were related to high prevalence of H. pylori infection in Iran. Accordingly, fecal–oral and oral–oral routes could be considered as the main pathways of transmission of H. pylori .     

GLP-1及其受体激动剂Exendin-4临床适应症的扩展

GLP-1及其受体激动剂Exendin-4是治疗糖尿病的一种理想药物,是近年来新的研究热点之一。近年发现,该类药物可从多个生理角度发挥功能,揭示其临床适应症可能有进一步的扩展空间。对GLP-1及Exendin-4的各种已知和潜在的临床适应症进行了概述,这些适应症除了各型糖尿病外,还包括肥胖症、神经系统和心脏的疾病以及其他各种潜在适应症。     

2015年值得关注的药物预测

回顾2014年值得关注的3种药物（Sovaldi、Anoro Ellipta和Zydelig）的上市和销售情况。重点介绍2015年值得关注药 物的适应证、上市申请、临床开发情况以及市场前景展望等     

三唑类抗真菌新药泊沙康唑和伏立康唑简介

随着侵袭性真菌感染的发病率和死亡率逐年增多,新近问世的新型抗真菌药物也越来越多。新一代广谱三唑类抗真菌药物泊沙康唑和伏立康唑,在体内和体外均有较强的抗真菌活性,临床上用其来预防和治疗侵袭性真菌感染。两药具有共有的作用机制,在抗真菌活性、药物代谢及安全性方面有着各自特点。分子结构上泊沙康唑和伏立康唑优于原有药物伊曲康唑和氟康唑,从而具备更强、更广的抗菌谱。两药的研发和应用表明抗真菌药物研究正朝着高效、广谱、低毒的方向发展,成为治疗各种类型真菌感染新的有力手段。然而,两药在临床研究和血药浓度监测方面仍待深入探究。本文将从分子结构、作用机制、适应症和药代动力学方面介绍两药,并对两药在未来的临床应用进行展望,为临床应用提供帮助。     

Refining the ethics of preimplantation genetic diagnosis: A plea for contextualized proportionality

Many European countries uphold a ‘high risk of a serious condition’ requirement for limiting the scope of preimplantation genetic diagnosis (PGD). This ‘front door’ rule should be loosened to account for forms of PGD with a divergent proportionality. This applies to both ‘added PGD’ (aPGD), as an add‐on to in vitro fertilization (IVF), and ‘combination PGD’ (cPGD), for a secondary disorder in addition to the one for which the applicants have an accepted PGD indication. Thus loosening up at the front has implications at the back of PGD treatment, where a further PGD rule says that ‘affected embryos’ (in the sense of embryos with the targeted mutation or abnormality) should not be transferred to the womb. This ‘back door’ rule should be loosened to allow for transferring ‘last chance’ affected embryos in aPGD and cPGD cases, provided this does not entail a high risk that the child will have a seriously diminished quality of life.     

Correlations of unfavorable movement characteristics in warmblood foals and mares with routinely assessed conformation and performance traits

New movement traits reflecting unfavorable movement characteristics were defined on the basis of detailed movement evaluations (DME) of warmblood foals and mares performed in connection with regular breeding events of the Oldenburg horse breeding societies in 2009 and 2010. DME information was available for 3374 foals and 2844 mares and used for correlation analyses with conformation information on 1987 mares from studbook inspections (SBI) in 2009 and performance information on 2758 mares from mare performance tests (MPT) in 2000 to 2008. Analyses of variance revealed few significant differences between scores for SBI and MPT traits in mares without and with indications of imbalance (IMB) in general or specific findings like irregular tail tone or posture (TTP). SBI scores for general impression and development were significantly lower and MPT scores for trot under rider tended to be higher in IMB-positive mares. Genetic parameters were estimated in linear animal models with residual maximum likelihood. Additive genetic correlations and Pearson correlation coefficients between univariately predicted breeding values indicated unfavorable genetic correlations of IMB and TTP with dressage-related conformation and performance traits. For SBI and MPT traits, we found similarities between the correlation patterns for DME traits in foals and mares. The results implied that breeding of dressage horses may benefit from revision of current movement evaluation and consideration of specific movement characteristics.