Bioactivity and Vitamins in Flash-heated Breastmilk

描述（由申请人提供）：母乳喂养有助于艾滋病毒的母婴传播，每年全世界儿童中发生的80万例艾滋病毒感染中有90%是由母乳喂养引起的，其中绝大多数在撒哈拉以南非洲。目前联合国儿童基金会/世卫组织的建议侧重于使母乳喂养更安全的挑战；指导方针包括将母乳热处理作为发展中国家艾滋病毒阳性母亲的官方婴儿喂养建议。本研究将评估家庭巴氏消毒母乳的营养和细菌学安全性。这些信息对于充分告知母亲这种喂养方式的风险和益处是必要的。本研究的总体目标是科学评估闪热（母亲可以在家中进行灭活艾滋病毒的方法）对母乳营养、免疫和抗感染成分的影响。加热的牛奶必须有足够的营养来支持生长发育，保持抗感染活性，以防止感染性疾病的发生。具体目的包括评估闪热对艾滋病毒感染母亲的母乳样品以下方面的影响：1)维生素含量和蛋白质消化率；2)关键生物活性蛋白（免疫球蛋白A、溶菌酶和乳铁蛋白）；3)抗菌活性。具体目标3是确定不同年龄的非洲婴儿接受热处理牛奶的饮食需求。以前已经从艾滋病毒阳性的南非妇女那里收集了50份母乳样本，并进行了快速加热。在加热和未加热的牛奶中，我们将测量和比较：a)已知对热敏感的维生素a、抗坏血酸、硫胺素、核黄素、吡哆醇、叶酸和B12的浓度；B)溶菌酶和乳铁蛋白的浓度和消化率；c)总抗原和slgA浓度及其对特定抗原（麻疹、肺炎链球菌、流感）的生物活性（通过结合）；D)分离的抗感染蛋白乳铁蛋白和溶菌酶的生物活性，通过细胞摄取，酶和杀菌活性；e)随着时间的推移，牛奶通过抑制大肠杆菌和金黄色葡萄球菌的生长而具有抗菌特性。从这些分析中获得的信息将用于线性规划，以预测由于加热所描述的牛奶营养成分的变化将如何影响儿童的总体饮食需求和相关成本。

DESCRIPTION (provided by applicant): Breastfeeding contributes to maternal to child transmission of HIV, which is responsible for 90% of the 800,000 HIV infections that occur each year among the world's children, the vast majority of which are in sub-Saharan Africa. Current UNICEF/WHO recommendations focus on the challenge of making breastfeeding safer; guidelines include heat treatment of breastmilk as an official infant feeding recommendation for HIV positive mothers in developing countries. This study will evaluate nutritional and bacteriologic safety of home pasteurized breastmilk. This information is necessary to adequately inform mothers of risks and benefits of this feeding alternative. The overall objective of this study is to scientifically evaluate the effect of Flash-heat (a method mothers can perform at home to inactivate HIV) on nutrient, immunologic and anti-infective components of breastmilk. Heated milk must be nutritious enough to support growth and development, retain anti-infective activity in order to prevent infectious morbidities. Specific aims include evaluation of impact of Flash-heat on the following aspects of breastmilk samples from HIV-infected mothers: 1) vitamin content and protein digestibility; 2) key bioactive proteins (immunoglobulin A, lysozyme and lactoferrin); 3) antibacterial activity. Specific aim 3 is to determine dietary needs of African infants of different ages receiving heat-treated milk. 50 breastmilk samples have been previously collected from South African women who are HIVpositive, and Flash-heated. In the available aliquots of heated and unheated milk we will measure and compare: a) concentrations of vitamins A, ascorbic acid, thiamine, riboflavin, pyridoxine, folate and B12, known to be relatively heat-sensitive; b) concentration and digestability of proteins lysozyme and lactoferrin; c) concentration of total and slgA and bioactivity (via binding) of each against specific antigens (measles, S. pneumoniae, influenza); d) bioactivity of isolated anti-infective proteins lactoferrin and lysozyme, via uptake into cells, enzymatic and bactericidal activity; e) antibacterial properties of milk via inhibition of growth of E. coli and S. aureus over time. Information from these analyses will be used in linear programming to predict how the described changes in nutrient content of milk due to heating would affect the overall dietary needs of the child and the associated costs.