RNA干扰在早产儿视网膜病中的研究进展

RNA干扰是指具有同源性的双链RNA能高效、特异地使靶mRNA发生降解,使基因转录后的mRNA不能表达而导致基因沉默的一种现象.RNA干扰在维持基因组稳定、保护基因组免受外源核酸侵入、基因表达调控等方面发挥重要生物学作用.RNA干扰作为基因沉默的一个工具,已被广泛用于基因功能研究、基因治疗和新药研究与开发等方面.早产儿视网膜病是发生于未成熟或低出生体重儿的增殖性视网膜病变,是儿童致盲的主要原因之一,血管新生是早产儿视网膜病的病理生理基础.RNA干扰技术在分析和研究目的 基因功能、抗肿瘤和病毒等方面取得了一些突破性进展,为增殖性视网膜病变的基因治疗提供了新思路. 该文对RNA干扰的机制特点及在早产儿视网膜病中的研究进展作以综述.     

Somatotype, nutrition, and obesity

The purpose of this investigation is to evaluate the somatotype characteristics of the studied group and search for a relation between somatotype, obesity, and particular features of nutrition. METHODS: Somatotype after Health & Carter (1990), nutritional status according to Body mass index (BMI), and nutrition determined by food-frequency questionnaires. RESULTS: Over 94% of the subjects in this study were distributed into five somatotype categories: 51.6% endomorphic mesomorphs, 17.1% mesomorph-endomorphs, 16.7% mesomorphic endomorphs, 6.1% balanced mesomorphs, and 3.0% ectomorphic mesomorphs, with a pronounced sexual dimorphism. Males were distributed into five categories: over 65% were endomorphic mesomorphs, and above 40 years of age the mesomorphy increased. Females were distributed into three somatotype categories: up to and above 40 years of age over 44% were mesomorphic endomorphs. In the most common somatotype categories, 1 of 5 subjects (from 21.4% to 19.9%) had normal body mass (< 25 kg/m2), 4 of 5 subjects (from 34.2% to 52.6%) were overweight (> 25 kg/m2) or obese (> 30 kg/m2) kg/m2 (from 44.4% to 27.5%). In the remaining eight categories, all subjects had normal body mass. Hyperenergetic, sodium- and fat-excess nutrition had an especially unfavorable influence.     

肥胖儿童脂质代谢及血压与ACE基因和ApoE基因多态性的相关研究

【目的】 探讨血管紧张素转换酶(angiotensin converting enzyme,ACE)基因和载脂蛋白E(apolipoprotein E,ApoE)基因多态性的分布及其多态性对健康和肥胖儿童的血压、脂质代谢影响。 【方法】 用PCR-RFLP及琼脂糖凝胶电泳法分析5~13岁的肥胖儿童(105例,男54人,女51人)及健康儿童(98例,男49人,女49人)ACE基因和ApoE基因的基因型,并测定两组儿童血清甘油三酯((TG)、总胆固醇(TC)、高密度脂蛋白胆固醇(HDLC)、低密度脂蛋白胆固醇(LDLC)浓度、血压、身高和体重。 【结果】 肥胖儿童具有较高的D/D基因型频率、D等位基因频率及ε4等位基因频率。D/D型儿童与ε4等位基因携带儿童具有较高水平的血TG、TC、LDLC-C及收缩压(SBP)、舒张压(DBP)、BMI和较低水平的血HDL-C。 【结论】 本地区健康及肥胖儿童ACE和ApoE基因存在多态性,且ACE和ApoE基因多态性对健康儿童及肥胖儿童的血脂代谢、体脂分布及血压均有影响。     

Vitamin K nutrition, metabolism, and requirements: current concepts and future research

In 2001, the US Food and Nutrition Board concluded that there were insufficient data with which to establish a RDA for vitamin K, in large part because of a lack of robust endpoints that reflected adequacy of intake. Knowledge of the relative bioavailability of multiple vitamin K forms was also poor. Since then, stable isotope methodologies have been applied to the assessment of the bioavailability of the major dietary form of vitamin K in its free state and when incorporated into a plant matrix. There is a need for stable isotope studies with enhanced sensitivity to expand knowledge of the bioavailability, absorption, disposition, and metabolism of different molecular forms of vitamin K. Another area for future research stems from evidence that common polymorphisms or haplotypes in certain key genes implicated in vitamin K metabolism might affect nutritional requirements. Thus far, much of this evidence is indirect via effects on warfarin dose requirements. In terms of clinical endpoints, vitamin K deficiency in early infancy continues to be a leading cause of intracranial bleeding even in developed countries and the reasons for its higher prevalence in certain Asian countries has not been solved. There is universal consensus for the need for vitamin K prophylaxis in newborns, but the effectiveness of any vitamin K prophylactic regimen needs to be based on sound nutritional principles. In contrast, there is still a lack of suitable biomarkers or clinical endpoints that can be used to determine vitamin K requirements among adults.     

母亲孕期膳食营养对儿童肥胖与代谢的影响

儿童肥胖是一个全球性的公共卫生问题,其发病原因与生命早期暴露及不良环境密切相关.孕期膳食营养影响着胎儿的宫内环境,进而对子代肥胖与代谢疾病的发病产生重要影响.本文对孕期能量摄入水平、各类膳食营养素摄人情况以及孕期膳食模式与儿童肥胖和代谢疾病发病关联的现有研究证据进行综述,总结孕期膳食营养对子代代谢的作用,对孕期合理膳食...     

RNAi-基因敲除技术在妇科领域中的应用

RNAi是存在于真核生物体内的一种阻断外源基因表达的自我防御体系。它是由双链RNA介导的使与其互补的具有同源序列的单链RNA进行特异性的降解。随着这几年RNAi研究的不断深入,RNAi的干涉机制逐渐被阐明。该文介绍了RNAi的干涉机制和在妇科肿瘤领域中的应用进展。RNAi技术必将成为妇科肿瘤领域基因功能研究、细胞信号传导以及基因治疗的一种强大的新型工具。     

不同营养治疗方法在妊娠期糖代谢异常中的应用

目的 探讨不同营养治疗方法对改善妊娠期糖代谢异常的代谢紊乱及妊娠结局的影响.方法 选择83例妊娠期糖代谢异常孕妇作为研究对象,孕30周前来营养门诊并按数字表法随机分为传统的食物交换份组(EFS组,42例)和基于血糖负荷概念的食物交换份组(FES+GL组,41例).分别采用相应的营养治疗方法进行干预直至分娩,观察不同的营养治疗方法对血糖及妊娠结局的影响.结果 FES+GL组营养治疗后每日食物血糖负荷值(145.9±26.3)明显低于FES组(179.9±28.9),差异有统计学意义(t=5.602,P＜0.01).FES+GL组营养治疗后的空腹血糖和餐后2 h 血糖[分别为(4.63±0.97)、(6.15±1.07)mmol/L]均较营养治疗前[分别为(4.96±0.81)、(9.13±1.61)mmol/L]明显下降(t值分别为2.237、11.202,P值均＜0.05).FES+GL组营养治疗后的餐后2 h血糖[(6.15±1.07)mmol/L]低于FES组[(6.86±1.26)mmol/L],差异有统计学意义(t=2.760,P＜0.05).FES+GL组孕妇总的并发症发生率为19.51%(8/41),低于FES组的26.19%(11/42),但差异无统计学意义(χ2=0.524,P＞0.05).结论 基于血糖负荷概念的食物交换份比传统食物交换份更容易控制血糖.这两种营养治疗方法对改善糖代谢异常孕妇的妊娠结局均有帮助.

Abstract：

Objective To explore the effect of different nutrition therapies on abnormal glucose metabolism during pregnancy and pregnancy outcomes. Methods The 83 cases of pregnant women withabnormal glucose metabolism who came to nutrition clinic were randomly divided into two groups before 30 weeks pregnancy: 42 cases in traditional food exchange serving group ( FES ) and 41 cases in foodexchange serving based on glycemic load group (FES + GL). Traditional food exchange serving and food exchange serving based on glycemic load were used as the different nutrition therapies for two groupsrespectively until the time of delivery. The influence of two nutrition therapies on the blood glucose andpregnancy outcomes were observed. Results The daily food glucose load (GL) after nutrition therapy in the FES + GL group ( 145.9 ± 26. 3 ) were significantly decreased than that of the FES group( 179.9 ± 28. 9,t =5. 602, P ＜ 0.01 ). Fasting plasma glucose (FPG) and 2 h postprandial glucose ( 2 h PG ) ( ( 4.63 ± 0.97 )and (6. 15 ± 1.07) mmol/L,respectively) after nutrition therapy in the FES ± GL group were significantlylower than that in pre-nutrition therapy ( (4. 96 ± 0. 81 ) and ( 9. 13 ± 1.61 ) mmol/L, t = 2. 237,11. 202,respectively,all P values ＜ 0. 05 ). The 2 h PG in the FES + GL group ( (6. 15 ± 1.07 ) rmmol/L) afternutrition therapy was significantly lower than that of the FES group ( (6. 86 ± 1. 26)mmol/L,t = 2. 760, P ＜0.05). 19.51%(8/41 )of the total incidence of complications in the FES + GL group was lower than that ( 11/42,26. 19% ) in the FES group, but the difference was not significant ( χ2 = 0. 524, P ＞ 0. 05 ).Conclusion FES based on GL was much easier to reduce blood glucose compared with FES. Two nutrition therapies can improve maternal and neonatal outcomes in pregnant women with abnormal glucose metabolism.     

“标本配穴”电针和限食干预对肥胖大鼠HPA轴及糖脂代谢的影响

目的 研究“标本配穴”电针和饮食控制对肥胖大鼠HPA轴及糖脂代谢的影响。方法 雄性Wistar大鼠随机分为5组,正常组（N）给予普通饲料喂养,模型组（M）给予高脂喂养,电针组（E）高脂喂养的同时给予“标本配穴”电针治疗,限食组（R）每只给予对照组摄食量的70%,电针+限食组（E+R）给予“标本配穴”电针结合饮食控制干预治疗,共干预8周。检测各组大鼠体重（BW）、血清糖脂（FPG、FINS、TG、TC）和ACTH、CORT水平变化,并检测下丘脑CRH含量。结果 (1) 与N组比较,M组BW及FPG、FINS、TG和TC均明显增加（P ＜0.01）,与M组比较,3个电针和饮食干预组BW及FPG、FINS、TG和TC均明显下降（P ＜0.01）,且E+R组下降程度优于E组和R组（P ＜0.05）;(2) 与N组比较,M组下丘脑CRH及血清ACTH、CORT均明显升高（P ＜0.01）,与M组比较,3个电针和饮食干预组CRH、ACTH及CORT均明显下降（P ＜0.01）,且E组效果优于R组（P ＜0.05）,而E+R组与E组比较无统计学差异（P ＞0.05）。结论 高脂饮食诱导的肥胖模型大鼠表现出HPA轴功能亢进,拮抗HPA轴亢进可能是“标本配穴”电针和饮食控制发挥减肥、改善糖脂代谢作用的途径之一。     

单纯性肥胖儿童脂代谢与LEPR及ApoE基因多态性的相关性研究

目的探讨单纯性肥胖儿童脂代谢与LEPR及ApoE基因多态性的相关性。方法常规苯酚-氯仿法抽提基因组DNA,用聚合酶链式反应-限制性片断长度多态性（PCR-RFLP）及聚丙烯酰胺凝胶电泳法分析135例单纯性肥胖儿童及84例健康儿童LEPR基因的第20外显子和ApoE基因的第4外显子基因型及等位基因变异频率,并测定两组儿童血清甘油三酯（triglyceride,TG）、总胆固醇（total choles-terol,TC）、高密度脂蛋白胆固醇（high density lipoprotein cholesterol,HDLC）、低密度脂蛋白胆固醇（lowdensity lipoprotein cholesterol,LDLC）浓度,并测定两组儿童身高和体重,按公式计算其体重指数（bodymass index,BMI）。结果本实验检出3种LEPR基因第20外显子的基因型,分别为：A/A型、A/G型、G/G型;4种ApoE基因第4外显子的基因型,分别为：E3/3型、E4/3型、E2/3型、E4/2型,未检出E2/2、E4/4纯合型。与健康儿童相比,单纯性肥胖儿童LEPR基因第3057位核苷酸G→A突变频率及ApoE基因第3934位核苷酸T→C（ε4）突变频率增高（P〈0.05）。与非ε4携带ApoE基因型个体比较,携带ε4基因的G/A型肥胖儿童的血TG,LDLC浓度升高,BMI增高;携带ε4基因的A/A型单纯性肥胖儿童血TC,TG,LDLC浓度升高,BMI亦增高,血HDLC下降,差异有显著意义（P〈0.05）。结论本地区健康及单纯性肥胖儿童存在LEPR基因第20外显子及ApoE基因第4外显子,存在基因多态性变化。LEPR基因与ApoE基因变异,可以明显影响儿童血脂及BMI,且有一定的协同作用。     

儿童青少年肥胖的医学营养治疗与HCH管理模式

肥胖已经成为严峻的全球性公共卫生问题。截至2014年,我国7岁以上学龄儿童青少年的超重率为12.2%,肥胖率为7.3%,共有3 496万人。2030年可达5 000万。儿童青少年肥胖的医学营养治疗,包括积极的高危人群筛查,肥胖儿童青少年的饮食、运动、生活方式综合干预等。上海儿童医学中心-上海潍坊社区服务中心医联体门诊采用“医院-社区-家庭(HCH)管理模式”对上海地区儿童青少年肥胖进行医学营养综合治疗,获得良好效果,值得进一步应用推广。     

Popular diets: correlation to health, nutrition, and obesity

OBJECTIVE: To examine the association between a range of health and nutrition indicators and popular diets. DESIGN: The Continuing Survey of Food Intake by Individuals (CSFII) 1994-1996 data were used to examine the relationship between prototype popular diets and diet quality as measured by the healthy eating index (HEI), consumption patterns, and body mass index (BMI). The prototype diets included vegetarian (no meat, poultry, or fish on day of survey) and non-vegetarian. The nonvegetarian group was further subdivided into low carbohydrate (less than 30% of energy from carbohydrate), medium (30% to 55%), and high (greater than 55% of energy). Within the high carbohydrate group, participants were classified as having Pyramid or non-Pyramid eating patterns. The Pyramid group was defined as 30% or less of energy from fat and at least one serving from the five major food groups in the USDA Food Guide Pyramid. Finally, the non-Pyramid group was further subdivided into low fat (less than 15% of energy from fat) and moderate fat (15% to 30% of energy from fat). In addition, a review of the published scientific literature was conducted; all studies identified were included in the review. SUBJECTS: 10,014 adults, aged 19 years and older, from the 1994-1996 CSFII were included in the analyses of extant data. More than 200 individual studies were included in the review of the literature. RESULTS: Analyses of the CSFII indicate that diet quality as measured by HEI was highest for the high carbohydrate Pyramid group (82.9) and lowest for the low carbohydrate group (44.6). Energy intakes were low for the vegetarians (1,606 kcals) and high carbohydrate/low fat group (1360 kcals). BMIs were lowest for women in the vegetarian group (24.6) and the high carbohydrate/low fat group (24.4); for men, the lowest BMIs were observed for vegetarians (25.2) and the high carbohydrate Pyramid group (25.2). Review of the literature suggests that weight loss is independent of diet composition. Energy restriction is the key variable associated with weight reduction in the short term. CONCLUSIONS: Diets that are high in carbohydrate and low to moderate in fat tend to be lower in energy. The lowest energy intakes were observed for those on a vegetarian diet. The diet quality as measured by HEI was highest for the high carbohydrate groups and lowest for the low carbohydrate groups. The BMIs were significantly lower for men and women on the high carbohydrate diet; the highest BMIs were noted for those on a low carbohydrate diet.     

Genetic information, obesity, and labor market outcomes

Economists have argued that obesity may lead to worse labor market outcomes, especially for women. Empirical methods to test this hypothesis have not thus far adequately controlled for the endogeneity of obesity. We use variation in genotype to predict variation in phenotype (obesity). Genetic information from specific genes linked to obesity in the biomedical literature provides strong exogenous variation in the body mass index and thus can be used as instrumental variables. These genes predict swings in weight of between 5 and 20 pounds for persons between five and six feet tall. We use additional genetic information to control for omitted variables correlated with both obesity and labor market outcomes. We analyzed data from the third wave of the Add Health data set, when respondents are in their mid-twenties. Results from our preferred models show no effect of lagged obesity on the probability of employment or on wages, for either men or women. This paper shows the potential of using genetic information in social sciences.     

个体化医学营养治疗对妊娠期糖尿病患者营养代谢的影响

目的：研究个体化医学营养治疗（MNT）对妊娠期糖尿病患者（GDM）营养代谢的影响。方法将2010年1月至2012年7月在首都医科大学附属北京同仁医院产科确诊为妊娠糖尿病并接受营养科MNT的87例GDM患者作为研究组,同时期未接受营养科MNT的76例GDM患者作为对照组,研究组内又分为血糖达标组40例和血糖不达标组47例,首次营养科就诊时记录孕12周建档、孕24周糖尿病筛查和分娩前各项指标,比较治疗前后空腹血糖、餐后2小时血糖、血清总蛋白、血清白蛋白、血红蛋白、甘油三酯及胆固醇等指标变化。结果①分娩前研究组空腹血糖和餐后2小时血糖均低于对照组,血红蛋白和高密度脂蛋白胆固醇均高于对照组,有显著性差异（ t值分别为0．006、0．039、0．000、0．008,均P＜0．05）;血清总蛋白、血清白蛋白、甘油三酯、总胆固醇、低密度脂蛋白胆固醇也高于对照组,但无无显著性差异（P＞0．05）;②研究组内血糖达标者与不达标者分娩前的血红蛋白、血清总蛋白、血清白蛋白、甘油三酯、总胆固醇、低密度脂蛋白胆固醇和高密度脂蛋白胆固醇7项指标均无显著性差异（P＞0．05）;③分娩前1周与建档时相比,研究组空腹血糖、餐后2h血糖、总蛋白和白蛋白明显下降,血红蛋白、甘油三酯、总胆固醇、低密度脂蛋白明显升高,有显著性差异（t值分别为2．185、1．152、－1．244、2．185、1．976、－1．865、－1．532、－0．567,均P＜0．05）。高密度脂蛋白胆固醇升高,但无显著性差异（P＞0．05）。结论 MNT可使GDM糖代谢有效改善,预防和纠正孕期贫血,但是对脂代谢影响有限。孕期生理变化是导致脂代谢变化的主要原因,以往将脂代谢用于妊娠期医学营养治疗效果的评价可能不妥。     

转基因水稻潮酶素标记基因在大鼠体内代谢的初步研究

目的初步探索hpt在大鼠消化道内降解的特点和肝脏、肾脏转移的可能性。方法48只成年雄性SD大鼠随机分为8组,每组6只,6组作为转基因组,2组作为非转基因组,分别喂饲转基因饲料和非转基因饲料两周。所有动物于试验结束当天喂饲后2、4、6、8、10和24h处死动物,取胃、空肠、回肠下段、盲肠、直肠的内容物。另取20只雄性SD大鼠随机分为2组,每组10只,转基因大米饲料与非转基因饲料喂饲大鼠4周,取其肝脏、肾脏。用PCR方法检测hpt片段在肠道和肝、肾脏器中的代谢情况。结果hpt基因在胃内容物中有少量未被降解之外,在小肠、盲肠及直肠内容物中,基因大部分已被降解。hpt基因在肠道的降解存在时间和片断依赖型。在试验周期内,肝、肾脏器中未捡出hpt基因片断。结论转基因水稻hpt基因在大鼠消化道内很容易降解,且不能在肝、肾脏器中被捡出。     

母代肥胖引起子代脂代谢紊乱的研究进展

目的 了解母代肥胖与子代脂代谢紊乱的关系及目前研究进展。方法 以“母代肥胖”、“子代”、“脂代谢”、“maternal obesity”、“offspring”、“lipid metabolism”等为关键词,查询PubMed、百度学术、中国期刊全文数据库、万方数据知识服务平台等的文献进行综述。结果 母代肥胖促进子代对脂类的消化和吸收可降低子代脂质的氧化反应、抑制子代脂质的合成和增加子代肝脏脂肪的蓄积。母代肥胖是子代发生脂代谢紊乱的危险因素,可通过DNA甲基化、非编码RNA转录和组蛋白乙酰化等多种途径导致子代表观遗传学的改变,进而对子代造成长久损伤。此外,母代肥胖可以导致子代肠道菌群结构的改变,降低肠道α-多样性。结论 母代肥胖不仅会增加自身患慢性非传染性疾病的风险,还会影响其子代的健康,特别是影响子代脂类的吸收和代谢。     

多囊卵巢综合征患者不孕的遗传学研究

多囊卵巢综合征是女性常见病和多发病,其发生主要受遗传控制,多数证实本病是常染色体显性遗传,一些基因位点已被提出,包括CYP11A、胰岛素基因以及胰岛素受体附近区域,研究较为深入的是胰岛素受体附近区域,已被两项独立研究证实,但是位于染色体19P13.3位点的相关基因仍等待去被证实。相关的研究已提供了一些潜在的导致多囊卵巢综合征的突变基因,包括Calpain10、IRS1、IRS2以及SHBG。这里从家系遗传学、细胞、分子遗传学方面阐明了多囊卵巢综合征的发病机理,将为该病大规模的基因系统筛查、新基因的发现及基因治疗提供了重要的理论依据和有力的工具。