妊娠期营养

从妊娠开始到哺乳期终止是母体经受一系列生理调节的过程。妇女在妊娠期间不仅要维持自身的营养需要,还要保证胎儿的生长发育及乳房、子宫和胎盘等发育的需要,也要为分娩和产后授乳作好营养贮备。适宜营养直接关系到胎儿、婴幼儿乃至青少年及成人体格、智力的全面发展,对母体及婴幼儿的健康有重要意义。一、孕妇营养对胎儿、婴儿的影响孕妇营养对子代的影响曾有过争议。目前,大多认为孕期营养对子代有明显影响。美国母亲食品及营养委员公,收集了有关孕期营养与其预后关系的大量资料后,提出孕期营养充足与否与下列7项指标的高低有关:①母、婴死亡率;②自然流产;③早产;④     

叶酸缺乏导致人类先天性异常的机制研究进展

叶酸是由喋啶核、对氨苯甲酸及谷氨酸3部分组成的一种维生素。叶酸在细胞生长、分化、修复和宿主防御等方面扮演重要角色,是DNA和RNA合成过程中需要的重要物质。叶酸作为甲基供体在基因调控所需的甲基化过程中也起重要的作用,人类叶酸缺乏可导致许多先天性异常的发生率明显上升,如：神经管发育缺陷（NTD）、颌面部畸形（如唇腭裂）、先天性心脏病（CHD）（尤其是流出道畸形和室间隔缺损）、泌尿和消化系统畸形等异常。另有许多国内外流行病学调查研究表明,母亲孕期适当补充叶酸可以有效的预防这些先天性畸形的发生。叶酸缺乏与人类先天性异常的发生密切相关。     

围孕期营养因素与先天性心脏病发病的关系

先天性心脏病是人体在胚胎发育时期受各种因素影响导致心脏及血管发育异常的先天性畸形.先天性心脏病是人类最常见的先天畸形,是导致婴儿发病和病死的重要原因.即使可以经过外科手术矫治畸形,先天性心脏病患儿也要面临各种手术并发症甚至疾病复发的风险,给社会带来巨大的经济压力.目前普遍认为先天性心脏病的发生受遗传因素和环境因素的共同影响.近年来围孕期营养因素与先天性心脏病的发病关系成为研究热点.研究结果显示,叶酸及其他围孕期营养素与先天性心脏病的发生有密切关系,围孕期母亲适当补充这些营养素可降低子代先天性心脏病的发生风险.该文就叶酸、维生素A、锌、维生素B、维生素E围孕期关键营养因素与先天性心脏病的关系,从病因、发病机制及预防方面进行综述,为疾病的预防提供基础.     

亚甲基四氢叶酸还原酶基因多态性与脑性瘫痪

亚甲基四氢叶酸还原酶(MTHFR)在调节血浆同型半胱氨酸水平和DNA甲基化中起重要作用,MTHFR基因突变可引起酶活性减低,使血浆同型半胱氨酸水平升高及DNA甲基化异常。研究发现MTHFR基因多态性与遗传性易栓症相关,可能引起包括脑性瘫痪在内的不良妊娠结局。     

同型胱氨酸尿症的发病机理

生化机理关于同型胱氨酸代谢的生化途径已有广泛的研究。如图1所示,同型胱氨酸是从食物蛋氨酸中得到的,即来自动物蛋白。蛋氨酸受S-腺苷蛋氨酸合成酶(蛋氨酸活化酶)的作用,经腺苷化转为腺苷蛋氨酸。此种化合物在人体代谢中为主要甲基供体,也被认为是“活性蛋氨酸”。几乎所有甲基化反应均利用S-腺苷-蛋氨酸作为供体底物。例如,S-腺苷-蛋氨酸是合成胆硷、肌酸、N-甲基烟酰胺、肾上腺素、儿茶酚胺和甲基化核酸的甲基供体。转甲基反应的结果使S-腺苷-同型半胱氨酸形成。此种化合物对进一步的转甲基反应有     

邻苯二甲酸二(2-乙己基)酯导致隐睾症发生跨代遗传的机制研究

目的 探讨增塑剂邻苯二甲酸二(2-乙己基)酯(DEHP)于性腺发育的关键时期作用于孕鼠(0),研究F1-F3代隐睾跨代遗传的演变情况及各代睾丸基因组DNA甲基化转移酶水平的改变情况.方法 妊娠SD大鼠随机分为两组:正常对照组和DEHP实验组,实验组自妊娠第七天(GD7)到第十九天(GD19)持续经口予以DEHP 750 mg·kg-1 ·d-1灌胃,观察子代隐睾发生情况,雌鼠受孕率;记录大鼠体重和睾丸、附睾重量以及AGD值,观察精子数量和质量;观察连续三代大鼠睾丸组织形态的演变情况,检测DNA甲基化转移酶变化情况.结果 孕鼠在孕期(GD7-GD19)暴露于DEHP,第一代(F1)隐睾发生率为30％,第二代(F2)隐睾发生率为12.5％,第三代(F3)未见隐睾发生;交配实验F1代受孕率50％,F2代75％,F3代100％;HE染色发现F1代睾丸生精上皮明显萎缩,生精细胞少,F2代有所改善,F3代形态趋于正常.Real Time-PCR、免疫组化和Western Blot表明DNA甲基化转移酶的表达随着遗传代数的增加而上调,差异有统计学意义.结论 DEHP损伤大鼠雄性生殖功能,通过改变DNA甲基化转移酶的表达,继而导致基因组印记甲基化修饰模式改变并遗传给下一代,从而使子代雄性生殖系统发育的关键性印记基因作用失衡,并最终导致子代产生隐睾,可能是导致生殖系统损害的重要毒理机制之一.     

妊娠压力与金属元素联合暴露对子代神经发育影响的研究进展

孕期环境对子代生长发育有重要影响.环境因素包括自然环境(空气、水、土壤等)和社会环境(睡眠剥夺、妊娠期压力、社会经济状况等).作为孕期不良社会环境的一种,妊娠压力对子代神经发育的影响日益引起研究者的重视.     

DNA甲基化与儿童白血病的临床研究进展

<正>DNA甲基化是研究最广泛的哺乳动物表观遗传学修饰,它提供了一种稳定的可遗传的基因沉默机制,与组蛋白修饰和其他的染色质相关蛋白一起,在调节基因表达和染色体结构方面起重要作用。DNA甲基化是指在DNA甲基转移酶(DNA methyl-     

DNA甲基化在癫(癎)发病机制及治疗中的研究进展

DNA甲基化是重要的表观遗传修饰,通过DNA甲基转移酶完成,与多种表观遗传学调控机制相互作用,参与调控基因表达和细胞分化的过程.目前在癫(癎)研究中发现了大量DNA甲基化相关改变,其在癫(癎)发病中的作用愈见明显.该文就DNA甲基化在癫(癎)发病机制中的研究进展进行了系统的分析和综述,并阐述了其在癫(癎)治疗上的应用和前景.     

孕妇锌营养及其对胎儿的影响

孕妇锌营养与胎儿生长发育关系密切。本文从孕妇孕期对锌的需求、利用、转运及目前用以反映其锌营养状况的指标等方面着手,综述近十年来国外对孕妇孕期锌代谢的研究。通过对孕妇孕期缺锌对胎儿影响的现察及动物实验的研究结果,进一步论述了为保证子代正常生长发育,防止因孕期缺锌所致的流产、先天畸形、宫内胎儿发育迟缓等不良后果以及孕妇加强孕期锌营养的重要性。     

Fetal Programming and the Risk of Noncommunicable Disease

The “developmental origins of health and disease” (DOHaD) hypothesis proposes that environmental conditions during fetal and early post-natal development influence lifelong health and capacity through permanent effects on growth, structure and metabolism. This has been called ‘programming’. The hypothesis is supported by epidemiological evidence in humans linking newborn size, and infant growth and nutrition, to adult health outcomes, and by experiments in animals showing that maternal under- and over-nutrition and other interventions (e.g., glucocorticoid exposure) during pregnancy lead to abnormal metabolism and body composition in the adult offspring. Early life programming is now thought to be important in the etiology of obesity, type 2 diabetes, and cardiovascular disease, opening up the possibility that these common diseases could be prevented by achieving optimal fetal and infant development. This is likely to have additional benefits for infant survival and human capital (e.g., improved cognitive performance and physical work capacity). Fetal nutrition is influenced by the mother’s diet and body size and composition, but hard evidence that the nutrition of the human mother programmes chronic disease risk in her offspring is currently limited. Recent findings from follow-up of children born after randomised nutritional interventions in pregnancy are mixed, but show some evidence of beneficial effects on vascular function, lipid concentrations, glucose tolerance and insulin resistance. Work in experimental animals suggests that epigenetic phenomena, whereby gene expression is modified by DNA methylation, and which are sensitive to the nutritional environment in early life, may be one mechanism underlying programming.     

父母超重/肥胖与子代孤独症谱系障碍的关系

目的 探讨母孕前父母超重/肥胖与子代孤独症谱系障碍（ASD）发生的关系。方法 选取ASD儿童36名（ASD组）及性别、年龄与之相匹配的72名正常儿童（对照组）纳入研究。采用问卷调查的方式收集母亲孕前两组儿童父母身高、体重以及母亲孕期增重等信息,采用单因素和多因素logistic回归法分析母孕前父母超重/肥胖与子代ASD的关系。结果 ASD组母孕前父亲超重/肥胖的检出率高于对照组（56% vs 32%,P=0.018）。单因素和多因素logistic回归分析均显示母孕前父亲超重/肥胖是子代发生ASD的危险因素（分别OR=2.66、2.58,P < 0.05）。结论 母孕前父亲超重/肥胖是子代罹患ASD的独立危险因素,因此在母亲妊娠前,父亲的体重指数应控制在正常范围内,以减少子代ASD的发生。     

Modifiable maternal exposures and offspring blood pressure: a review of epidemiological studies of maternal age, diet, and smoking

Prenatal programming of adult disease is well established in animals. In humans the impact of common in utero exposures on long-term offspring health is less clear. We reviewed epidemiology studies of modifiable maternal exposures and offspring blood pressure (BP). Three maternal exposures were identified for review and meta-analyzed where possible: smoking during pregnancy, diet, and age at childbirth. Meta-analysis suggested there was a modest association between higher offspring BP and prenatal exposure to smoke (confounder-adjusted beta = 0.62 mm Hg, 95% confidence interval: 0.19-1.05, I = 16.4%). However, the level of confounder adjustment varied between studies, which in some studies attenuated the association to the null. There was no strong evidence that any component of maternal diet during pregnancy (maternal protein, energy, calcium, and various other nutrients) influences offspring BP. The results of studies of maternal age varied and there was strong evidence of heterogeneity in the pooled analysis. The association with maternal age, if present, was modest (confounder-adjusted beta = 0.09 mm Hg/y, 95% confidence interval: -0.03 to 0.21, I = 89.8%). In sum, there is little empirical evidence that the maternal exposures reviewed program offspring BP. Other components of offspring health may be more susceptible to effects of programming in utero.     

硫化氢供体对动脉粥样硬化大鼠肾上腺髓质素及心钠素的影响

目的 内源性硫化氢(H2S) 作为心血管调节的新型气体信号分子,在动脉粥样硬化(AS)发生发展中发挥重要保护作用。本研究拟探讨H2S 供体对AS 大鼠肾上腺髓质素(ADM)和心钠素(ANP)的影响。方法 雄性SD 大鼠随机分为对照组、AS 组和AS+NaHS 组。AS 组和AS+NaHS 组大鼠给予连续3 d 腹腔注射维生素D3 及高脂饲料连续喂养8 周。AS+NaHS 组大鼠腹腔注射H2S 供体NaHS。油红O 染色法观察大鼠主动脉根部及冠状动脉斑块面积变化;敏感硫电极法测量血浆H2S 含量;放射免疫法检测血浆ADM 及ANP 含量。结果 与对照组相比,AS 大鼠主动脉根部及冠状动脉可见明显AS 斑块形成,血浆H2S 含量明显降低,ADM 含量升高,ANP 含量明显降低(P2S 含量明显升高,ADM 含量明显降低,ANP 含量显著升高(P结论 H2S 对AS 大鼠血管活性多肽ADM、ANP 具有重要的调节作用。     

Neurodevelopmental sequelae of postnatal maternal care in rodents: clinical and research implications of molecular insights

Parental care plays an important role in the emotional and cognitive development of the offspring. Children who have been exposed to abuse or neglect are more likely to develop numerous psychopathologies, while good parent-infant bonding is associated with improved resiliency to stress. Similar observations have also been reported in non-human primates and rodents, suggesting that at least some neurodevelopmental aspects of parent-offspring interactions are conserved among mammals and could therefore be studied in animals. We present data to suggest that frequency of licking and grooming provided by the dam during a critical period in development plays an important role in modifying neurodevelopment. These findings are examined in the broader context in which exposure to other sensory modalities such as vision or hearing during a specific period in development shapes brain development with functional consequences that persist into adulthood. We also discuss recent rodent work showing that increased frequency of licking and grooming provided by the dam during the first week of life is associated with changes in DNA methylation of promoter elements that control expression of these genes and behavior. The stability of DNA methylation in postmitotic cells provides a possible molecular scaffold by which changes in gene expression and behavioral traits induced by postnatal maternal care are maintained throughout life. Finally, the relevance of findings reported in rodents to those noted in non-human primates and humans are assessed and the research and clinical implications of these observations for future work are explored.     

子痫前期对母婴肠道菌群影响的研究进展

子痫前期是妊娠期特有的并发症,影响母婴健康.肠道菌群在人体代谢和免疫方面发挥着重要的调节作用,并与许多疾病相关.研究表明,子痫前期的发生发展可导致母亲肠道菌群的改变,甚至与子代肠道菌群的定植与发展密切相关.该文就子痫前期对母婴肠道菌群影响的相关研究进行综述,为子痫前期相关母婴并发症的预防及治疗提供新思路.引     

Nutrition in adolescent pregnancy

Prevention of unintended adolescent pregnancy is a primary goal of the American Academy of Pediatrics and of many health providers. Nevertheless, many adolescents become pregnant every year in America. Pediatricians therefore should be aware of nutritional recommendations for pregnant adolescents to provide optimal care. The importance of nutrition during pregnancy is here reviewed from a pediatric perspective. Pregnancy, particularly during adolescence, is a time of extreme nutritional risk. The adolescents most likely to become pregnant are often those with inadequate nutritional status and unfavorable socio-economic background. There is increasing evidence of competition for nutrients between the growing pregnant adolescent and her fetus. Also, the prenatal environment has been implicated in the development of obesity, cardiovascular disease, and diabetes in both the mother and her offspring. Many adolescents have poor diet quality and poor knowledge of appropriate nutrition; these habits may not change during pregnancy. Current knowledge and recommendations regarding the intake of energy, calcium, and folate are discussed in detail.     

Anxiety disorders before birth and self-perceived distress during pregnancy: Associations with maternal depression and obstetric, neonatal and early childhood outcomes

Background

Maternal perinatal mental health has been shown to be associated with adverse consequences for the mother and the child. However, studies considering the effect of DSM-IV anxiety disorders beyond maternal self-perceived distress during pregnancy and its timing are lacking.

Aims

To examine the role of maternal anxiety disorders with an onset before birth and self-perceived distress during pregnancy for unfavourable maternal, obstetric, neonatal and childhood outcomes.

Study design

DSM-IV mental disorders and self-perceived distress of 992 mothers as well as obstetric, neonatal and childhood outcomes of their offspring were assessed in a cohort sampled from the community using the Munich-Composite International Diagnostic Interview. Logistic regression analyses revealed associations (odds ratios) between maternal anxiety disorders and self-perceived distress during pregnancy with maternal depression after birth and a range of obstetric, neonatal and childhood psychopathological outcomes.

Results

Lifetime maternal anxiety disorders were related to offspring anxiety disorders, but not to offspring externalizing disorders. Analyses focussing on maternal DSM-IV anxiety disorders before birth yielded associations with incident depression after birth. In addition, self-perceived distress during pregnancy was associated with maternal depression after birth, preterm delivery, caesarean section, separation anxiety disorder, ADHD, and conduct disorder in offspring.

Conclusion

Findings confirm the transmission of anxiety disorders from mother to offspring. Apart from maternal anxiety, self-perceived distress during pregnancy also emerged as a putative risk factor for adverse outcomes. The finding that maternal anxiety disorders before birth yielded less consistent associations, suggests that self-perceived distress during pregnancy might be seen as a putative moderator/mediator in the familial transmission of anxiety.     

不同孕期母亲免疫水平对婴儿牛奶蛋白过敏的影响

目的 探讨不同孕期母亲Th1/Th2免疫水平与婴儿牛奶蛋白过敏（CMPA）之间的关联。方法 选取2016年7月至2018年12月于山东省潍坊市益都中心医院及青州市中医院就诊的单胎健康孕妇及其子代为研究对象。检测母亲孕中期、孕后期的白细胞介素（IL）-2、干扰素-γ（IFN-γ）、IL-4和IL-10水平,并分别于出生后1年内进行CMPA问卷调查,对临床怀疑CMPA的婴儿进行食物回避及牛奶口服激发试验,将符合CMPA的48例婴儿纳入CMPA组,其余977例正常婴儿纳入对照组。对CMPA婴儿进行单因素分析,并采用泊松回归分析不同孕期母亲各Th1/Th2型细胞因子水平与CMPA之间的关联。结果 CMPA的检出率为4.68%,临床表现包括消化系统症状、皮肤表现、呼吸系统症状及其他表现。单因素分析结果显示,CMPA组母亲食物过敏、母亲过敏性疾病史的发生率均明显高于对照组（P < 0.05）,母乳喂养率明显低于对照组（P < 0.05）。CMPA组的母亲IL-2（孕中期和孕后期）、IFN-γ（孕后期）较对照组明显降低（P < 0.05）。母亲孕后期低IFN-γ及孕中期、孕后期低IL-2与婴儿CMPA存在显著关联（P < 0.05）;校正母乳喂养、母亲食物过敏及母亲过敏性疾病史等因子后发现,母亲孕后期低IL-2、低IFN-γ与婴儿CMPA仍存在显著关联（P < 0.05）。结论 孕后期母体的Th1型细胞因子水平下降,可能会导致胎儿的免疫改变,从而增加其子代出生后罹患CMPA的风险。