母乳成分与纯母乳喂养婴儿体重增长速率的关系

目的 探讨母乳成分对纯母乳喂养婴儿体重生长速率的影响。方法 选取定期进行儿童保健的138 例纯母乳喂养足月单胎婴儿及其乳母作为研究对象。在定期儿童保健时间点进行婴儿体重、身长及头围的测量,采用Z 积分计算生长速度,并根据ΔZ 积分将研究对象分为生长不良组（ΔZ 积分 ≤ -0.67）、生长速度低下组（-0.67 结果 生长不良组、生长速度低下组体重ΔZ 积分显著低于正常对照组（P P 结论 成熟乳母乳成分可短时间内在一定程度上影响纯母乳喂养婴儿的体重增长速率,乳母应均衡膳食,提高成熟乳质量以维持婴儿良好的体格生长速率。     

The distribution of lead in milk and the fate of milk lead in the gastrointestinal tract of suckling rats

Milk can be a significant source of lead (Pb) for young mammals, including humans. Certain essential trace elements have previously been shown to be specifically associated with particular milk components and such associations often increase bioavailability. Thus, the first goal of this study was to determine the distribution of Pb in cream, casein, and whey fractions of various milks under various conditions using 203Pb as a tracer. In rat milk almost 90% of the Pb was found to be associated with the casein micelles, regardless of: 1) whether the milk was labeled in vivo or in vitro; b) whether the milk was fresh or frozen; and c) the added concentration of Pb (over the range 0.01-75 micrograms/ml). The remainder of the Pb was approximately equally distributed between cream and whey. A virtually identical pattern of Pb distribution was observed with bovine milk. Pb added to infant formula also associated predominantly with casein micelles, although the Pb content of this fraction was significantly less than with rat and bovine milks. The second goal of the study was to determine if Pb remained associated with casein as it traversed the gastrointestinal tract of infant rats. For this purpose, rat pups aged 15-16 days were gavaged with 203Pb-labeled rat milk, and lumenal contents from the stomach and small intestine were collected 2 h later. Differential centrifugation of the homogenized lumenal contents showed that in the stomach the Pb was associated primarily with the casein curd. By the time chyme reached the distal small intestine, Pb was found predominantly in a fraction that was not precipitable by high-speed centrifugation (thus, not intact casein micelles), but was nondialyzable. We conclude that Pb in milk is protein bound and remains this way as it traverses the stomach and proximal small intestine of the infant rat.     

母乳脂联素浓度变化与婴儿生长发育的相关性研究

目的 分析母乳脂联素(adiponectin,APN)浓度变化,探讨其与婴儿血APN的相关性,及其与0～1岁婴儿生长发育的关系.方法 选择2008年3-12月在上海国际和平妇婴保健院出生的健康足月儿及其母亲73对入组.收集母亲产后2、4、l3、26周母乳,用ELISA法测定母乳APN浓度.分析母乳APN浓度变化趋势及其与婴儿体格生长指标的关系,并运用多元回归方法分析与婴儿生长指标相关的影响因素.且于出生26周时收集婴儿血标本,探讨母乳APN与婴儿血APN的相关性.结果 产后2、4、13、26周母乳APN浓度分别为:14.62(5.93～140.40)、7.32(2.04～29.35)、6.84(2.72～15.65)、4.88(1.12～13.38)μg/L.其中产后2周母乳APN与婴儿13、26、52周年龄别体重Z分值(WAZ)均呈负相关(P＜0.05);4周母乳APN与婴儿4、13、26、52周WAZ、身长别体重Z分值(WLZ)、体重指数Z分值(zBMI)均呈负相关(P＜0.05);13周母乳APN与婴儿13、26、52周WAZ、WLZ、zBMI均呈显著负相关(P＜0.01);26周母乳APN与婴儿52周WAZ、WLZ、zBMI呈负相关关系(P＜0.05).多元线性回归分析发现母乳APN均为13、26及52周WAZ、WLZ、zBMI最重要的影响因素.婴儿26周血APN与13、26周母乳APN呈正相关(P＜0.05).结论 随泌乳期的延续,母乳APN浓度呈下降趋势.母乳中APN浓度越高,婴儿体重则明显偏低.婴儿血APN与母乳APN显著相关.

Abstract：

Objective To investigate the variation of human breast milk adiponectin (APN)concentration during lactation, analyze the relationship of APN concentrations in human breast milk with APN in infant serum, determine the association between maternal milk APN and infant body proportionality in the first year of life, and the period of greatest human milk exposure.Method Subjects included 73mother-infant pairs from Shanghai International Peace Maternity & Child Health Hospital.Maternal milk was collected at 2, 4, 13, 26 weeks and infant serum was collected at 26 weeks.The concentration of APN in maternal milk and infant serum were measured with commercially available ELISAs (R&D Systems).Weight-for-age Z-scores (WAZ) , length-for-age Z-scores ( LAZ ) , weight-for-length Z-scores ( WLZ ) and body mass index Z-scores ( zBMI ) of infants up to 1 year of age were calculated using World Health Organization (WHO) standards.Then the variation of maternal milk APN was investigated, the correlation between maternal milk APN and infant serum APN was analyzed; multivariate regression analysis was used to analyze covariates correlated with infant body proportionality, meanwhile determined the association between maternal milk APN and infant anthropometrics.Result The concentration of APN in maternal milk at 2, 4,13, 26 weeks was respectively (14.62 μg/L, 5.93-140.40 μg/L), (7.32 μg/L, 2.04-29.35 μg/L),(6.84 μg/L, 2.72-15.65 μg/L) and (4.88 μg/L, 1.12-13.38 μg/L).Higher milk APN in postpartum 2weeks was associated with lower infant WAZ at 13, 26 and 52 weeks ( P ＜ 0.05 ).Milk APN in postpartum 4 weeks was inversely related to infant WAZ, WLZ, zBMI at 13, 26 and 52 weeks ( all P ＜ 0.05 ).Meanwhile, milk APN in postpartum 13 weeks had significantly negative correlation with infant WAZ, WLZ,zBMI at 13, 26 and 52 weeks (P＜0.01).Milk APN in postpartum 26 weeks also was inversely associated with infant WAZ, WLZ and zBMI at 52 weeks (P ＜0.05).After adjusting covariates like birth weight using multivariate regression analysis, milk APN level is the most important influence factor to infant WAZ, WLZ,zBM1 at 13, 26 and 52 weeks.There was a positive correlation between maternal milk APN and infant serum APN at 13, 26 weeks.Conclusion Milk APN concentration declines throughout lactation.Maternal milk APN may play a vital role in the growth and development of breastfed infants, particularly closely associated with infant weight.Infant serum APN clearly correlated with maternal milk APN.     

The growth rate of the human cranial base between nasion and inion

The growth rate of the human cranial base between nasion (N)-tuberculum sellae (Ts) and tuberculum sellae-internal occipital protuberance (=Twining's line (Tw)) were calculated in proportion to nasion-inion (N-I) distance and expressed in two cranial base ratios: and The growth rate of the whole cranial base showed a notable stability and a given ratio apparently prevails through into later life.     

Intestinal glucose transport in suckling rats fed artificial milk with and without added epidermal growth factor

Epidermal growth factor (EGF), a potent mitogen present in milk, is postulated to play an important physiologic role in the ontogeny of the intestine. An artificial rat milk, free of EGF, was developed and fed to newborn rats in an effort to evaluate the physiologic role of EGF on intestinal glucose transport. Comparisons were made between mother-fed (group 1) and artificially fed pups (group 2). Group 1 was divided into two subgroups to received either the EGF vehicle (group 1-A) or twice daily subcutaneous injections (0.1 micrograms/g body weight/day) of EGF (group 1-B). Group 2 was divided into four subgroups: formula without EGF (group 2-A), formula with 62 ng/ml of EGF (group 2-B), formula with 200 ng/ml EGF (group 2-C), and formula without EGF but added anti-EGF IgG (40 ng/ml) plus subcutaneous injections of 1 micrograms anti-EGF twice daily (group 2-D). Treatment regimens were initiated on day 3 and assays performed on day 11 of life. Glucose transport was measured using gut "sheet" preparations in all but group 2-C, which utilized brush border membrane preparations. Group 1-B showed a significant (p less than 0.03) increase in gut length (47.5 +/- 1.2 versus 42 +/- 0.9 cm) and an increase (p less than 0.03) in both Vmax (10.2 +/- 0.5 versus 7.2 +/- 0.3 nM/mg tissue) and Km (2.74 +/- 0.49 versus 1.20 +/- 0.19 mM) compared to group 1-A.(ABSTRACT TRUNCATED AT 250 WORDS)     

Impact of maternal overweight and obesity on milk composition and infant growth

Overweight and obesity (OW/OB) impact half of the pregnancies in the United States and can have negative consequences for offspring health. Studies are limited on human milk alterations in the context of maternal obesity. Alterations in milk are hypothesized to impact offspring development during the critical period of lactation. We aimed to evaluate the relationships between mothers with OW/OB (body mass index [BMI] ≥25 kg/m²), infant growth, and selected milk nutrients. We recruited mother–infant dyads with pre‐pregnancy OW/OB and normal weight status. The primary study included 52 dyads with infant growth measures through 6 months. Thirty‐two dyads provided milk at 2 weeks, which was analysed for macronutrients, long‐chain fatty acids, and insulin. We used multivariable linear regression to examine the association of maternal weight status with infant growth, maternal weight status with milk components, and milk components with infant growth. Mothers with OW/OB had infants with higher weight‐for‐length (WFL) and BMI Z‐scores at birth. Mothers with OW/OB had higher milk insulin and dihomo‐gamma‐linolenic, adrenic, and palmitic acids and reduced conjugated linoleic and oleic acids. N6 long‐chain polyunsaturated fatty acid (LC‐PUFA)‐driven factor 1 was associated with higher WFL, lower length‐for‐age (LFA), and lower head circumference‐for‐age Z‐scores change from 2 weeks to 2 months in human milk‐fed infants, whereas N6 LC‐PUFA‐driven factor 5 was associated with lower LFA Z‐score change. Human milk composition is associated with maternal pre‐pregnancy weight status and composition may be a contributing factor to early infant growth trajectory.     

Response of bifidobacterium species to growth promoters in human and cow milk

We used an in vitro assay to study and compare the growth-promotional activity of protein and nonprotein components in human milk (HM) and cow milk (CM) samples for infant strains of Bifidobacterium species. HM samples varied considerably in growth-promotion activity for Bifidobacterium bifidum var pennsylvanicus, Bifidobacterium infantis, and Bifidobacterium breve. Pooled CM samples showed similar but less variable levels of activity when compared with HM samples. Separation of milk samples by ultrafiltration into protein nitrogen and nonprotein nitrogen (NPN) fractions revealed that the bifidobacteria growth-promotion activity of HM was associated primarily with the NPN fraction, whereas activity in CM whey was found in both protein nitrogen and NPN fractions. Testing of purified CM whey proteins showed that alpha-lactalbumin and lactoferrin were potent growth promoters, showing greater activity for B. infantis and B. breve than for two strains of B. bifidum. Conversely, N-acetylglucosamine and purified gastric mucin were highly active for B. bifidum strains but inactive for other Bifidobacterium species. Collectively, the data indicate that both protein nitrogen and NPN factors in HM and CM promote the growth of bifidobacteria and suggest that Bifidobacterium species differ in responsiveness to protein and oligosaccharide growth promoters.     

Diet fat and oral insulin-like growth factor influence the membrane fatty acid composition of suckling rat small intestine.

BACKGROUND: Insulin-like growth factor- plays an important role in small intestine development. The presence of insulin-like growth factor-1 and the complexity of the fatty acid composition in breast milk suggests that intestinal development may be influenced by manipulating the levels of these components. METHODS: To determine whether a physiological dose of insulin-like growth factor-1 would influence sucrase and lactase activity levels, 10-day-old suckling rat pups were treated with an oral gavage of insulin-like growth factor-1. Four diets differing in fat composition were fed to lactating dams. Brush border membranes were isolated from jejunal and ileal segments of suckling rat small intestine. Fatty acid analysis of choline and ethanolamine phospholipids was performed. RESULTS: Insulin-like growth factor-1 was found to have no effect on the sucrase and lactase activities of suckling rats. Changes in the diet fat composition of the mother's diet indirectly influenced the fatty acid composition of suckling rat small intestine. Insulin-like growth factor-1 decreased ileal C20:4n-6 levels. A correlation was observed between lactase activity and C20:4n-6 and C22:6n-3 levels. As C20:4n-6 levels increased, lactase activity appeared to decline. Increased lactase activity was observed when C22:6n-3 levels increased. CONCLUSIONS: The changes observed in C20:4n-6 levels in response to oral insulin-like growth factor-1, combined with the apparent trend of increased lactase activity with declining levels of C20:4n-6, may be of significance in the development of the small intestine in early life.     

Influences of maternal dietary intake and suckling on breast milk lipid and fatty acid composition in low-income women from Brasilia, Brazil

Diet has a strong effect, while suckling stimulus is believed not to influence breast milk fatty acids. The effect of dietary pattern and suckling on the fatty acid composition of Brazilian women's breast milk was studied. A cross-sectional study was conducted with low-income women living in the central region of Brazil, where dietary DHA is not readily available. Fore and hind milk fatty acids were collected from 77 women on day 15+/-1 postpartum, and information on maternal characteristics and dietary habit was taken. The effect of suckling stimulus was measured by the changes between fore and hind milk. The mean body mass index (BMI) of volunteers was 23.7+/-3.2 kg/m(2), and the milk lipid concentration was 4.8+/-1.2 g/dl. A mixture of traditional and western type of dietary habit, high in fat and sugar was observed. The fatty acids of the subject's milk were 41.93+/-1.42% saturated, 33.31+/-1.67% monounsaturated and 25.03+/-5.23% polyunsaturated (wt/wt). The DHA level in the milk was 0.34+/-0.19%, similar to the values found in milk of many western societies. DHA and 18:3n-3 levels increased from fore to hind milk (p<0.05). Correlation existed mostly between dietary components and milk 16:0 and oleic acid (18:0). An analysis of classes of fatty acids in milk showed oleic acid (18:0) to present a negative correlation with all milk fatty acid classes. The results suggest that breast milk fatty acids of Brazilian women reflect a western maternal dietary pattern and are influenced by the suckling.     

生长激素与肠道菌群相关性研究进展

人生长激素（hGH）由垂体前叶嗜酸性粒细胞合成,可通过胰岛素样生长因子-1(IGF-1)对生长和代谢发挥作用。GH的缺乏或分泌不足导致的矮小症称为生长激素缺乏症（GHD）,其具体病因及确切机制仍未完全阐释清楚。近年来,随着对肠道微生物菌群的认识及研究的深入,发现GH-IGF-1轴与肠道菌群存在相关性。文章就GH-IGF-1轴与肠道菌群关系的研究进行了阐述。     

Nutrient composition of human milk

A complex interplay of maternal homeostatic mechanisms influences nutrient transfer to nursing infants, and with a few exceptions, excess maternal intake or a moderate deficiency in the maternal diet does not appreciably alter nutrient transfer to infants unless it has persisted for some time. Milk vitamins D and K contents, even in apparently well-nourished women, may not always provide adequate amounts for infants. Investigations provide evidence that human milk possesses many unique characteristics and that maternal and environmental influences are stronger than previously recognized and appreciated. A complete body of knowledge does not exist to serve as a basis for dietary recommendations to ensure optimal nutrition for mothers and infants. The success of lactation usually is measured in terms of infant performance, and cost and consequence to the mother are seldom considered. Human milk feeding is recommended for the entire first year of life, but few studies focus on the nursing dyad for more than 3 months' duration. Continued study is needed so that nutritional adequacy may be maintained and appropriate dietary guidance can be provided. When human milk feeding is not practiced, modern and reliable data on human milk constituents and their significance to infants also are essential for the preparation of formulas, especially those not based on bovine milk. The adequacy of human milk substitutes cannot be predicted from compositional analysis because of possible differences in compartmentalization and molecular form of nutrients, and such preparations must be evaluated using specific indices of nutrient use, together with traditional anthropometric measures in infants.     

The influence of metoclopramide on the composition of human breast milk.

The breast milk prolactin (PRL) has been claimed to play a role in the control of electrolyte composition of the milk. Since metoclopramide has been shown to increase milk production in humans, we have made an attempt to investigate the production, the PRL and sodium concentrations in milk with (group I) and without (group II) maternal metoclopramide treatment (5 days, 30 mg/day). Both groups consisted of 11 mothers and their full-term newborn infants. The daily milk production was significantly higher in the treated group (276.4 +/- 36.6 vs 150.9 +/- 25.3 ml/day, p less than 0.01). The PRL measured by RIA was similar in the milk samples of the metoclopramide treated and control groups (80.5 +/- 17.7 vs 90.7 +/- 27.3 ng/ml). The sodium concentration in the milk of mothers taking metoclopramide was 22.1 +/- 1.6 mmol/l and 24.3 +/- 3.2 mmol/l in the control group (p = 0.59). On the 5th postnatal day the plasma PRL of the newborns of mothers treated with metoclopramide does not differ from the values of the control babies (29.8 +/- 2.6 vs 30.7 +/- 2.4 ng/ml) indicating that the amount of metoclopramide transferred into the milk has no apparent influence on the hypothalamo-hypophyseal axis of the neonate. In conclusion: the maternal metoclopramide treatment augments the milk production without having any effect on the PRL and sodium concentration of human "mature" milk.     

双歧杆菌对母乳成分的影响及其与婴儿过敏性疾病的关系

目的通过给孕母、乳母补充益生菌双歧杆菌,观察双歧杆菌对母乳成分的影响及其与婴儿过敏性疾病发病的关系。方法选择知情同意的孕妇,自孕36周开始口服双歧杆菌,分娩后继续服用直到母乳喂养结束,同时选择对照组口服安慰剂,取初乳及成熟乳测细胞因子及免疫球蛋白(IgA、sIgA、TGF-β1、TGF-β2、IL-10、sCD14);婴儿随访到2岁以确定湿疹及其他过敏性疾病。结果口服双歧杆菌的孕妇初乳中TGF-β1、TGF-β2水平低于对照组,IL-10水平高于对照组,成熟乳中sCD14高于对照组。母乳中TGF-β水平低的孕妇的孩子2岁内患过敏性疾病率低。口服双歧杆菌对母乳中IgA、sIgA水平无影响。结论在怀孕晚期及哺乳期口服双歧杆菌可降低母乳中TGF-β1、TGF-β2水平,母乳中后两者水平降低与母乳喂养婴儿低敏感性有关。     

Breast-feeding among teenage mothers: milk composition, infant growth, and maternal dietary intake

Information on breast-feeding was obtained from 25 mothers recruited from four high school programs for teenaged parents. Subjects were visited monthly 1-9 times (mean 3.7 visits) during the first 10 months of lactation to measure infant growth and maternal dietary intake and to collect a breast milk sample. Of 24 mothers visited more than once, 21 (88%) breast-fed for more than 3 months, and at least nine continued beyond 6 months. Compared to the nutrient content of milk samples from adult women, milk of teenage mothers was significantly lower in lactose, magnesium, calcium, potassium, and sodium. However, the differences in magnesium, calcium, and potassium may have been due to differences in the timing of sample collection. On the basis of infant growth, milk volume was judged to be adequate for 88% of the infants. Mean maternal energy and protein intakes were 2,897 kcal and 115 g, respectively; mean intakes of calcium, potassium, vitamin A, riboflavin, niacin, and vitamin C exceeded the National Research Council's Recommended Dietary Allowances (RDA) for lactation, while iron and thiamine intakes averaged 84% and 94% of the RDA, respectively. It is concluded that with active counseling teenage mothers are capable of successful lactation.     

The effect of Ramadan on maternal nutrition and composition of breast milk

BACKGROUND: There are many advantages of breast milk for infants. Many factors can affect the volume and composition of breast milk. One of them is the maternal diet. The objective of this study is to determine the effect of Ramadan fasting on maternal nutrition and breast milk composition. METHODS: A total of 21 breast-feeding mothers aged between 17 and 38 years who fasted during Ramadan month and volunteered to give milk samples were surveyed. The ages of the infants were between 2 and 5 months. The study was performed during Ramadan and 2 weeks after the end of Ramadan. RESULTS: The results showed that during Ramadan, zinc, magnesium and potassium levels in breast milk decreased significantly (P<0.05). The mother's weight increased approximately 1 kg after Ramadan. Changes in body mass index of the mother were not statistically significant. A significant decrease in vitamin A intake was observed after Ramadan (P < 0.05). During Ramadan, energy and most nutrient intakes except protein and vitamins A and C were found below daily recommended dietary allowances necessary for lactating women. CONCLUSIONS: Ramadan fasting had no significant effect on the macronutrient composition of the breast milk and consequently the growth of the infants. There were significant differences in some of the micronutrients such as zinc, magnesium and potassium. The nutritional status of lactating women was affected by Ramadan fasting. All of the nutrient intakes (except vitamins A, E and C) decreased during Ramadan. For these reasons, it would seem prudent to excuse lactating women from fasting during Ramadan.