卵子发育过程中组蛋白的动态变化

表观遗传修饰是指不改变DNA序列的可逆性修饰,包括DNA甲基化、RNA干涉、基因组印迹和组蛋白密码等多方面,在生物体生长发育过程中对基因表达和调控有重要作用。在卵子发育过程中,卵母细胞经历了一系列的表观遗传动态修饰,这一表观遗传成熟过程对于卵子的减数分裂及发育能力至关重要。其中组蛋白的转录后修饰及不同组蛋白的替换对异染色质的形成及卵母细胞基因组重塑过程起关键作用。现对卵子发育过程中组蛋白甲基化、乙酰化、磷酸化等共价修饰及不同组蛋白替换的研究现状做一总结。     

卵子发育过程中组蛋白的动态变化

表观遗传修饰是指不改变DNA序列的可逆性修饰,包括DNA甲基化、RNA干涉、基因组印迹和组蛋白密码等多方面,在生物体生长发育过程中对基因表达和调控有重要作用.在卵子发育过程中,卵母细胞经历了一系列的表观遗传动态修饰.这一表观遗传成熟过程对于卵子的减数分裂及发育能力至关重要.其中组蛋白的转录后修饰及不同组蛋白的替换对异染色质的形成及卵母细胞基凼组重塑过程起关键作用.现对卵子发育过程中组蛋白甲基化、乙酰化、磷酸化等共价修饰及不同组蛋白替换的研究现状做一总结.     

DNA甲基化与microRNA相互作用的研究进展

表观遗传修饰是一种遗传外的调控机制,包括DNA甲基化(DNA methylation)、基因组印迹(genomic imprinting)、染色体修饰(chromosome modification)、组蛋白修饰(histone modification )及microRNA(miRNA)调控状态(microRNA regulation)等方式.DNA甲基化和miRNA作为重要的表观遗传学调控机制,在不同水平调控基因表达,不仅参与机体正常生长发育的调节,而且影响肿瘤发生、发展和转移的过程.     

卵母细胞发育和受精中的重编程及对雄原核重编程的影响

哺乳动物发育过程中细胞的重编程是当前细胞生物学、转化医学等领域研究的热点之一,因其在体细胞核移植、诱导多能干细胞及再生医学中的应用前景引起了广泛关注。表观遗传学修饰是重编程的主要内容,包括DNA甲基化、组蛋白翻译后修饰、基因组印迹、非编码RNA调控等,这些均可通过不同的机制调控基因组的表达。如卵母细胞发育与成熟过程伴随着基因组的从头甲基化、减数分裂相关基因的去甲基化和组蛋白翻译后的修饰等。此外,受精中,卵母细胞又与进入其中的雄原核发生相互作用,为雄原核基因组的去甲基化等过程提供重编程的环境。总结近年来关于卵母细胞发育和受精过程中重编程机制的研究进展及在胚胎发育中的意义,并探讨自然生殖状况下卵母细胞环境对外源性雄原核重编程的影响。     

辅助生殖技术与胚胎DNA甲基化

表观遗传修饰,尤其DNA甲基化在控制细胞表达中发挥重要作用。高甲基化的DNA与基因沉默有关,低甲基化的DNA可以激活基因的转录,哺乳动物中70%~80%的Cp G位点被甲基化。DNA的甲基化状态并不像基因组那样稳定,在原始生殖细胞(primordial germ cells,PGCs)和早期胚胎阶段发生了一系列重组,即甲基化模式擦除、甲基化模式重新建立和甲基化模式维持。发达国家通过辅助生殖技术(assisted reproductive technology,ART)出生的婴儿已占1%~3%,并不断增长。ART方案的多样性和基因组印迹疾病的罕见性导致ART过程与印迹障碍发病率间的因果关系复杂化。除早产的发生率增加外,ART过程可导致配子及胚胎发生异常的表观遗传修饰和重组。脐疝-巨舌-巨体综合征(Beckwith-Wiedemann syndrome,BWS)、普达-威利综合征(Prader-Willi syndrome,PWS)等均为最具有代表性的基因组印迹疾病。     

脂肪酸合成酶表观遗传学调控的研究进展

脂肪酸合成酶(fatty acid synthase, FASN)在肿瘤和能量代谢性相关疾病中表达异常上升,且与多种表观遗传学调控机制相关。研究FASN的表观遗传学调控可以深入阐明FASN在疾病发生发展中的作用,为纠正异常表达的FASN提供新思路。本文综述了Fasn基因DNA甲基化、FASN mRNA甲基化和甲基化读码器蛋白、微小RNA与长链非编码RNA、组蛋白H3与H4磷酸化与乙酰化修饰以及FASN蛋白的翻译后修饰等FASN表观遗传学的调控机制,为通过表观遗传学靶点发挥对FASN的抑制作用提供新证据。     

多囊卵巢综合征的表观遗传学机制研究进展

遗传和环境等多种因素共同参与多囊卵巢综合征(PCOS)的发生与发展,两种因素交互作用所导致的临床表现可以用表观遗传修饰加以解释,但其具体作用机制还存在很多未知。表观遗传学是在DNA碱基序列不变的前提下引起的基因表达或细胞表观型变化的一种遗传现象,与PCOS发病相关的表观遗传修饰包括DNA甲基化、X染色体失活、组蛋白修饰、基因组印迹及非编码RNA调控等。微小RAN(mi RNAs)在卵巢组织广泛表达,在卵巢功能调节中发挥重要作用,参与细胞增殖、分化、凋亡等多种生物学过程,因此与PCOS的发生密切相关。探索表观遗传学在PCOS发病机制中的作用,为PCOS的预防、诊断与治疗提供新的思路。     

表观遗传学及其应用研究进展

近年来,表观遗传学方面的研究受到人们的广泛关注,表观遗传学是指不涉及DNA序列改变的基因或者蛋白表达的变化,并可以在发育和细胞增殖过程中稳定传递的遗传学分支学科,主要包括DNA甲基化,组蛋白共价修饰,染色质重塑,基因沉默和RNA编辑等调控机制。随着研究的深入,人们发现表观遗传学与多种疾病的发生发展有关,本文就表观遗传学的主要内容及其在相关疾病中的应用做一综述。     

DNA甲基化及其影响因素

在人类基因组中,DNA甲基化是一种重要的表遗传修饰,它与多种疾病发生密切相关。DNA甲基化在基因转录过程中起着重要的作用,与组蛋白修饰、染色质构型重塑共同参与转录调控。目前研究发现,基因组中DNA甲基化的水平与DNA甲基转移酶(DNMT)、组蛋白甲基化、饮食与环境、RNA干扰和病毒感染等多种因素有关。     

运动参与儿童早期发育表观遗传调控的认识进展

在儿童早期发育过程中,表观遗传的动态编程一方面与婴幼儿时期的膳食平衡密切相关,同时也与儿童的身体运动紧密相连,它们共同影响了表观遗传修饰的上游代谢平衡,因此更完整地体现了儿童发育过程中遗传与体内环境的交互作用。为此,本文介绍了运动对机体表观遗传修饰的影响以及对下游功能基因的调控作用,重点强调了运动参与DNA甲基化、染色体组蛋白修饰和miRNA调控三个不同层面的表观遗传作用机制的文献进展。本文的介绍对儿童早期发育中的运动需求,尤其是儿童早期发育阶段的亲子运动提供了更为系统的表观遗传学依据。     

企业职工高尿酸血症与血压、血脂、血糖的相关性研究

目的探讨企业职工高尿酸血症（HUA）与血压、血脂、血糖的相关性,为企业进行健康管理提供依据。方法以中国石油长庆油田公司各下属企业为抽样单位,整群随机抽取2个单位,每个单位中所有的HUA者作为HUA组,共720人;同时在尿酸水平正常者中随机选取620人为正常组。通过Logistic回归分析HUA与年龄、性别、血压、血脂、血糖的关系。结果HUA合并高血压、高血脂、空腹m糖受损任意一项、两项、三项的比例均远高于正常组（OR值分别为：4．036,2．562,4．174）。多因素Logistic回归发现：男性、收缩压、总胆固醇、三酰甘油、低密度脂蛋白胆固醇是HUA的危险因素（OR值分别为7．736,2．309,1．721,2．761,1．411）;高密度脂蛋白胆固醇为HUA的保护因素（OR值为0．211）。结论HUA存在性别差异,且与血压、血脂密切相关。企业对职工的健康管理应充分考虑多危险因素的综合作用,全面的进行健康教育及干预。     

癌缺氧病因及预防和治疗

目的 探讨癌及安阳林州市食管癌高发原因及癌病因预防和治疗措施.方法 对林州市食管癌等疾病现场进行调查,在进行10余年统计分析基础上,综合分析了全国156篇文献成果.结果 提出癌缺氧病因学说,使用制氧机、按摩器、饮用纯净水治疗恶性肿瘤,取得良好效果,改水能够大幅降低林州市居民食管癌发病率、死亡率.结论 癌可能是由于机体长...     

Recruitment and retention challenges and successes

Objective: Addressing health disparities requires well designed, culturally adapted research. However, recruiting/retaining minority participants has often been challenging. We present strategies used to successfully recruit and retain rural Hispanic women during a breastfeeding education intervention.

Design: This study involved a two-group repeated measures quasi-experimental design with assessments at seven intervals between enrollment and 6 months postpartum. Participants (Hispanic women?≥?15 years old) were recruited through a regional hospital.

Results: We successfully met our recruitment goals, most women contacted were enrolled (46 of 58), and 100% completed the study.

Discussion: Research staff with ties within the community helped establish trust. Using bilingual study materials, simple language, and an interpreter addressed language/literacy concerns. Phone assessments facilitated participation as transportation was an issue. Accommodating requests to deliver or mail study materials and providing incentives were important. Extra effort was needed to maintain contact when phone service was disrupted or participants moved. Keys to success were persistence, flexibility, and alleviating barriers to participation.     

初产妇与经产妇焦虑抑郁状态分析及干预

目的：分析初产妇、经产妇心理状态特点,以便采取更有效的干预措施。方法筛选2014年6月至2015年1月在咸阳市旬邑县妇幼保健院产科门诊产前检查的健康初产和经产妇各60名,孕周为28~40周。入组时用焦虑自评量表( SAS)、抑郁自评量表(SDS)对两组孕妇进行心理评定,并给1次支持性心理干预(40~60分钟),1周后再次用SAS、SDS对两组孕妇进行评定分析。结果经产妇干预前SAS(50.73±3.45)、SDS(49.13±3.86)评分明显高于初产妇SAS(42.45±2.08)、SDS(41.77±2.21),差异均有统计学意义(t值分别为-15.921、-12.817,均P<0.01);干预后两组SAS、SDS评分均比干预前明显降低,差异均有统计学意义(t值分别为14.999、15.413;15.724、15.832,均P<0.01);干预后经产妇 SAS(38.61±5.02)、SDS(39.10±3.03)评分明显高于初产妇SAS(34.88±3.31)、SDS(32.01±4.27),差异均有统计学意义(t值分别为-4.805、-10.489,均P<0.01)。结论初产妇和经产妇均伴有焦虑、抑郁情绪,干预前后经产妇抑郁、焦虑情绪均较初产妇明显,支持性心理干预能有效改善孕妇的不良情绪。     

Continuity and change in neighborhood disadvantage and adolescent depression and anxiety

We used data from the Fragile Families and Child Wellbeing Study which includes a sample of adolescents of age 15 at the most recent wave (between 2014 and 2017) from mainly low-income urban families in the United States, to examine the association between neighborhood poverty entries and exits and adolescent depression and anxiety. In addition, we examined whether these associations differed by gender. Adolescents who consistently lived in disadvantaged neighborhoods had the highest level of depression and anxiety. Those who entered poor neighborhoods were more depressed than those who never lived in poor neighborhoods. Those who exited poor neighborhoods showed no significant difference in depression and anxiety compared to those never lived in poor neighborhoods. Furthermore, these associations applied to adolescent girls only and were not statistically significant for boys. The results suggest that neighborhood poverty has cumulative negative impacts on adolescent mental health and disproportionally affects adolescent girls. Reducing neighborhood poverty would substantially improve the health of adolescents, especially girls, which would reduce health disparities.     

Enabling positive change: Progress and setbacks in HIV and sexual and reproductive health and rights

At a point in history when the future of sexual and reproductive health including HIV looks particularly uncertain, it is helpful to recognise that many of the challenges currently faced are neither new nor insurmountable. Reflecting on past achievements and lessons learned helps us to have confidence that positive change is feasible. This paper reflects on some of the changes observed in countries like India and Mozambique and identifies a range of factors which need to coalesce to enable these developments, along with specific contextual factors. It is the combination of these influences rather than any one of them alone that brought about the change in the three instances described – fostering a positive political response to HIV in its early years in India; bringing about policy reform on abortion in Mozambique; and increasing contraceptive prevalence and age at marriage in some districts in Bihar, India. Change is always fragile and susceptible to setbacks, but change-seekers can learn in the process and gain renewed hope that progress can and often does take place if they persevere.     

儿童青少年超重肥胖评价方法及SPSS和SAS实现

超重肥胖已成为世界各国儿童青少年面临的重大公共卫生问题之一。现行的儿童青少年超重肥胖筛查标准不统一,逐条评价或自行编写程序容易出错且效率较低。本研究以中国学龄儿童青少年超重与肥胖筛查标准为例,详细介绍了国际和中国共四种评价儿童青少年超重肥胖的方法和步骤,结合具体案例详细介绍其应用方法,同时编制SPSS和SAS程序包和解...     

Car ownership and the association between fruit and vegetable availability and diet

Objective

Nearly all research on the food environment and diet has not accounted for car ownership — a potential key modifying factor. This study examined the modifying effect of car ownership on the relationship between neighborhood fruit and vegetable availability and intake.

Methods

Data on respondents' (n = 760) fruit and vegetable intake, car ownership, and demographics came from the 2008 New Orleans Behavioral Risk Factor Surveillance System. Shelf space data on fresh, frozen, and canned fruits and vegetables were collected in 2008 from a random sample of New Orleans stores (n = 114). Availability measures were constructed by summing the amount of fruit and vegetable shelf space in all stores within defined distances from respondent households. Regression analyses controlled for demographics and were run separately for respondents with and without a car.

Results

Fruit and vegetable availability was positively associated with intake among non-car owners. An additional 100 m of shelf space within 2 km of a residence was predictive of a half-serving/day increase in fruit and vegetable intake. Availability was not associated with intake among car owners.

Conclusions

Future research and interventions to increase neighborhood healthy food options should consider car ownership rates in their target areas as an important modifying factor.