Fresh Human Milk Research Articles

Feeding the low-birth weight infant: V. Effects of taurine, cholesterol, and human milk on bile acid kinetics

This study was conducted to compare the influence of diet on the physiologic changes in bile acid kinetics, intraluminal bile acid concentrations, conjugation patterns, and nutrient lipid absorption, which occur postnatally. Preterm infants, 31–35 wk gestation, were fed one of four diets: (a) human milk pasteurized at 62 °C for 30 min, 55% from a pooled source, 35% from the infant's own mother, with the remainder (∼10%) being fresh human milk; (b) an adapted infant formula (F1; (c) F1 supplemented with taurine. 30 μmol/dl. (F2); and (d) F1 with both taurine. 30 μmol/dl, and cholesterol, 9.0 mg/dl, to a total of 12.7 mg/dl, the levels found in human milk (F3). In all infants, the bile acid pool size increased nearly twofold between 11 and 35 days, irrespective of dietary regimens. Taurine conjugation of bile acids predominated in all infants at 11 days of age and at 35 days in those infants fed human milk or the taurine-supplemented formulas. In taurine-supplemented formulas, the conjugation pattern did not influence bile acid kinetics. However, the bile acid pool and intraluminal bile acid concentrations were significantly greater in infants fed human milk at all ages, suggesting that human milk feeding, per se, uniquely influences intestinal and possibly hepatic function independent of developmental factors.

Immunohistochemical localizations of alpha-lactalbumin in human breast lesions in relation to secretory activity.

Alpha-lactalbumin (LA) was isolated and purified from fresh human milk and injected into rabbits for antiserum production. By a PAP technique, LA was demonstrated in the cytoplasm of secretory (26 positive cases out of 26 examined cases) and resting (11/43) normal mammary glandular cells from operated human breasts. Some epithelial cells in the cases of mammary dysplasia (53/229), fibroadenoma (15/94) and carcinoma (10/183), and of gynecomastia (1/12) showed positivity. Histochemical staining features, reticular, granular and compact, corresponded to the secretory state of the cells. The diffuse and sporadic distribution of LA-positive cells within the mammary lobules and foci would suggest the character of biological alterations. Moreover, LA secretion may be affected by the menstrual status of patients. LA has never been detected in normal parenchymal cells of the skin, stomach, colon, liver, pancreas, lung, testis, ovary, uterus, placenta, umbilical cord, thyroid or salivary gland. The immunohistochemical examination for LA, therefore, has no significant role as a tissue marker in histopathologic diagnosis of breast cancer, but it could serve as a specific marker for the mammary gland, especially its differentiation.

Fat Digestion in Very Low-Birth-Weight Infants: Effect of Addition of Human Milk to Low-Birth-Weight Formula

The possible compensatory role of human milk lipase in the digestion of dietary fat was examined in a group of very low-birth-weight infants. Fat excretion was studied in 15 preterm infants of gestational age 26 to 33 weeks and birth weight 660 to 1,695 gm. The amount and composition of fecal fat were determined in stools collected for 72 hours. Eight infants were fed Similac 24 LBW exclusively and seven infants were fed a mixture of fresh human milk (40%) and formula (60%). Fat excretion was lower in infants fed a mixture of human milk and formula than in infants fed formula only (4.7% -+/- 0.50% vs 11.9% +/- 1.4% of intake, respectively). Excretion of calcium soaps, when expressed as percent of total fat, was higher in the group fed the human milk-containing diet (18.9% +/- 13.5%), than in the group fed formula only (6.8 +/- 2.5%); however, the absolute amounts excreted were similar in both groups (65 +/- 46 and 45 +/- 17 mg/kg/day, respectively). The lower fat excretion in infants fed a mixture of fresh human milk and formula could be related to the lipase present in human milk. These data suggest that human milk lipase probably contributes to the digestion and absorption of dietary fat in the "tiny premature" infant.

Bacteriostasis of Escherichia coli by milk. VI. The in-vitro bacteriostatic property of Gambian mothers' breast milk in relation to the in-vivo protection of their infants against diarrhoeal disease.

A one-year field-study has been carried out in a diarrhoea-endemic area in West Africa to determine the relationship between the bacteriostatic activity of fresh human milk for Escherichia coli in vitro and freedom from diarrhoea of the infant recipients of the milk. The specific contribution of E. coli gastroenteritis to gastrointestinal diseases of infants in general is not known, nor is its particular role in the Gambian infants studied. During the study period, however, both enteropathogenic and toxigenic strains of E. coli were isolated. The incidence of diarrhoea in Gambian infants of seven age-groups from 2 days to 12 months was not significantly correlated with the bacteriostatic activity of milk. This was due rather to absence of diarrhoea in babies fed on low-activity milk than illness in those receiving highly bacteriostatic milk. Indeed, very active milk appeared to protect recipients almost completely, including seven babies of over 3 months of age, five of them during the rainy season, when the risk was high. Babies receiving lower-activity milk experienced more diarrhoea. In a situation where diarrhoeal disease is multifactorial, field evaluation of the protective action by one antibacterial property of milk is difficult. A better understanding of in vivo protection is important, and the factors which have to be taken into account are discussed.

Prostaglandins in Human Milk

Levels of prostaglandin E2 and prostaglandin F2 alpha were measured by radioimmunoassay in aliquots of foremilk and hindmilk obtained at different stages of lactation (colostrum, transitional, and mature milk) from six healthy nursing mothers who delivered at term. Immunoreactive prostaglandin E2 and prostaglandin F2 alpha were detected in all fresh human milk samples, but not in cows' milk-based formulas. Further studies are necessary to investigate the role of these hormones in the physiologic function, the extrauterine adaptation, and the cytoprotective effect on the gastrointestinal tract in the breast-fed human infant.

Detection of alpha-lactalbumin in breast lesions and relationship to estrogen receptors and serum prolactin.

Alpha-lactalbumin, the B protein of lactose synthetase secreted by the mammary epithelial cells, was isolated and purified from fresh human milk and injected into rabbits for antibody production. Indirect immunofluorescence (IIF) was done on various types of breast lesions to assess the relationship, if any, between histologic type and production of alpha-lactalbumin. Fifty percent of fibroadenomas and fibrocystic disease and 63% of infiltrating ductal carcinoma showed positive reaction. No false positives were found on IIF of alpha-lactalbumin of several tumors of nonmammary tissue. These findings suggest that IIF for alpha-lactalbumin may be helpful in ascertaining the site of origin of metastatic breast tumors. However, serum alpha-lactalbumin was detected by radioimmunoassay in only 10% of women with infiltrating ductal carcinoma, indicating that this may not be a useful marker for the presence of breast cancer at least by the method employed. This discrepancy between serum and tissue alpha-lactalbumin may be due to the short half-life of serum alpha-lactalbumin or to the lack of secretion of the protein into the blood. There was no apparent relationship between the presence of estrogen receptors or serum prolactin and alpha-lactalbumin in the 27 mammary carcinomas investigated.

Lead Content of Milk and Infant Formula

A survey to determine the lead content of early-infant food sources was conducted in the District of Columbia, Samples were collected from various lots of national brands of infant formula and evaporated milk, cartons of nonfat dry milk, containers of homogenized cow's milk and human milk from volunteer mothers, Data indicate that the concentration of lead in infant formula, evaporated milk and nonfat dry milk exceeds that in fresh cow's milk and human milk.

Changes of Lipids and Fatty Acid Compositions in Fresh and Frozen Human Milk during Various Stages of Lactation

Changes of Lipids and Fatty Acid Compositions in Fresh and Frozen Human Milk during Various Stages of Lactation

The effect of unheated human milk on the intestinal flora of preterm infants

There is a significant difference in the prevalence of intestinal infections between breast and bottle fed infants. Human milk may also have a protective function against neonatal septicaemia/meningitis and necrotizing enterocolitis, both conditions in which enteric organisms may be of importance in pathogenesis. These effects have been ascribed to antimicrobial factors in the milk, many of which are destroyed by heat, though pasteurization is less damaging than boiling. The effects of feeding fresh (sometimes frozen, never heated) human milk, pasteurized human milk and a modified dried cow's milk on the intestinal flora of immature, often very ill, infants in a neonatal intensive care unit has been studied. Twenty babies were investigated with median gestational age 32 weeks (range 28-37) and birth weight 1430 g (range 760-1920). Fourteen of the 20 had one or more antibiotic courses during the study period of 5 weeks. Unlike healthy term infants, the flora did not become stabilized for several weeks after birth. The numbers of infants colonized with E.coli, Klebsiella or Enterobacter did not differ in those fed fresh human milk or a modified dried cow's milk. The only obvious effects of human milk (fresh or pasteurized) were that the number of infants colonized with Str.faecalis and clostridia were reduced, and bifidobacteria were somewhat more common. The reduction in numbers of enterobacteria was considerably less than that expected in healthy mature breast fed babies.

BREAST MILK MACROPHAGES

Animal studies suggest that preterm infants gavage fed human breast milk receive pretection against enteric infection by the presence of macrophages (BMM), as well as immunoglobulins. We have been concerned about the effects of collection, storage, route of administration and other factors which may alter the survival of BMM.Samples of fresh human breast milk from healthy mothers 3 mo. postpartum were collected into plastic containers. BMM were separated by dilution 1:3 with phosphate buffered saline, centrifugation, and resuspension in saline or veronal HCL buffer. Cells were examined by microscopy, counted, and viability tested by phagocytosis of trypan blue dye. Aliquots of BMM were exposed to alterations in temperature to simulate storage procedures (-5 to 56°C), pH changes to simulate gastric vs duodenal feedings (2-8), alterations in osmolality to simulate mixing BMM with infant formulas (200-400 mOsm/kg water), and addition of albumin to simulate variations in formula protein content.Total BMM counts decreased with increasing postpartum age. Freezing markedly decreased survival, but heating to pasteurization did not. At pH above 7.2 survival and phagocytosis decreased, but the cells survived lowered pH ranges. Osmolality alterations produced no changes, but the addition of albumin diminished phagocytosis. We conclude that methods of procuring and feeding breast milk may markedly affect survival and phagocytic ability of BMM.

Breast Milk Banks: The New Model

Present evidence seems to suggest increasingly that fresh human milk has a protective role in the syndrome of acute necrotizing enterocolitis. For this reason (and many others), there appears to be an understandable increase in interest in the development of breast-milk banks. Considerable information already exists concerning the organization of such banks in the early decades of the present century and prior to that time. However, the milk stored in such earlier banks was not usually fresh, as it was primarily required for feeding rather than for the control of bacterial colonization of the intestine.

Galactothermin, a reversibly heat-precipitable protein of human milk at neutral pH.

1. A protein, aggregating at body temperature and solubilizing when cooled, was isolated from fresh human milk at neutral pH and studied for some of its physical, chemical and immunological properties. The name ;galactothermin' is proposed for this protein. 2. Isolation and purification of galactothermin involved casein removal from skim milk at pH4.64 followed by centrifugal fractionation of residual protein-containing solutions repeatedly heated and cooled between 40 degrees C and 0 degrees C at pH7.3. 3. The molecular weight by ultracentrifugal analysis and the minimum molecular weight by sum of amino acid residues were 11400 and 14000 respectively. The sedimentation coefficient s(25,w) was 1.05S and the diffusion coefficient was 7.15x10(-7). Reversible aggregation is favoured by increase in protein concentration, ionic strength, temperature, time and approach to the isoionic point of 7.27 from either acidic or alkaline conditions. 4. Among the amino acid residues, proline predominates and non-polar species account for two-thirds of the total. Cysteine and cystine are absent. Analysis of galactothermin showed it to be essentially free of hexose, sialic acid, calcium and phosphate. 5. Galactothermin is antigenic in the rabbit as evidenced by the passive cutaneous anaphylaxis test. Single precipitin lines are produced in immunodiffusion tests. 6. By electrophoresis in polyacrylamide gel at pH4.0 only one sharp band is produced.

Metabolism of vitamin D in animals. V. Isolation of vitamin D sulfate from mammalian milk.

1. The present authors have attempted to elucidate whether there may be possible occurrence of water-soluble vitamin D sulfate in fresh mammalian milk.2. Water-soluble vitamin D sulfate was isolated as its water-insoluble barium salt from the aqueous layer of fresh deproteinized milk.3. After repeating careful analyses, about 204I.U. of vitamin D was shown to be present in 1 liter of fresh cow's milk in a water-soluble form, whereas about 36I.U. per liter in a lipid-soluble form. In case of fresh human milk, it was estimated to be about 950I.U. per liter in a water-soluble form while 15.7I.U. in a lipid-soluble form.

有機チオール化合物による砒素解毒に関する実験的研究

1. In observing the polarographic catalytic wave of protein by making arsenic acid at various concentrations act on fresh human milk, fresh cow's milk, regulated powdered milk, and milk on the market, no decrease in the degree of the SH activity of milk protein due to the addition of arsenic can be detected. In this instance when the concentration of arsenic acid is gradually increased to a certain point, the reductive wave of arsenic appears on the heel of the proteinic wave. The arsenic acid concentration required to have the appearance of such an arsenic wave is 6 γ/cc in the case of fresh human milk; 5 γ/cc in fresh cow's milk; 4 γ/cc in regulated powdered milk; and 3 γ/cc in milk sold on the market.2. In drawing the polarographic curve of the reductive wave of arsenic by addition of milk at various concentrations to a hydrochloric arsenic acid solution, the arsenic wave falls in proportion to the addition of milk protein. The percentage of the fall in the amplitude of arsenic wave is greatest in fresh cow's milk followed by milk on the market regulated powdered milk and fresh human milk in the order mentioned.3. The rate of decrease in the amplitude of the arsenic wave in fresh human milk and the gelatin-protein of an equal concentration is greater in the latter. Therefore, it is obvious that the reaction between milk protein and arsenic is in no way associated with the SH-group.4. By applying the Langmuir's formula to these results, it has been confirmed that the reactions are induced by the action of surface activity of the milk proteins.

有機チオール化合物による砒素解毒に関する実験的研究

1. In the estimation of freely reacting SH-group of milk proteins by the electric photometer, the Kajita method is modified so as to use ammonium sulfate, (NH3)2SO4, in deproteinization-defatting processes.2. The quantity of the freely reacting SH-group of milk proteins is greatest in regulated powdered milk dissolved to the concentration of the whole milk, followed by that in fresh human milk and milk on the market.3. Even when the arsenic acid solution is made to act on liquid milk, no decrease in the freely reacting SH-group of milk protein can be recognized. In other words, no binding occurs between the freely reacting SH-group arsenic.

ACIDIFICATION OF THE URINE BY INFANTS FED HUMAN MILK AND WHOLE COW'S MILK

Acidification of the urine was studied with two groups of infants, each group consisting of four infants between 2 and 6 months of age: Group I received fresh or pasteurized human milk and Group II received whole cow's milk on evaporated milk and water without additional carbohydrate. The mean titratable acidity of the urine of infants of Group I was 3 meq/m2/12 hr compared with 35 meq/m2/12 hr for infants of Group II. The rates of excretion of ammonia were 7 and 28 meq/m2/12 hr by infants of Group I and II, respectively. After administration of ammonium chloride (4 gm/m2/day) for 2 days, the titratable acidity increased to 6 meq/m2/12 hr in Group I and to 34 meq/m2/12 hr in Group II. The mean rates of excretion of ammonia increased to 21 and 36 meq/m2/12 hr, respectively. The greater titratable acidity of the urine of infants of Group II is attributed primanly to the greater amounts of phosphate in the urine (mean, 35 mmol/m2/12 hr excreted by infants of Group II compared with 3 mmol/m2/12 hr by infants of Group I). The greater rate of excretion of ammonia by infants of Group II is attributed jointly to the prolonged administration of a diet with relatively great residue of anions and, perhaps, to the greater availability of glutamine and other precursors of ammonia.

EQUIVALENCE OF PASTEURIZED AND FRESH HUMAN MILK IN PROMOTING NITROGEN RETENTION BY NORMAL FULL-TERM INFANTS

Twenty-nine nitrogen balance studies were performed with 10 normal full-term infants fed fresh human milk either from the breast (eight nitrogen balance studies with four infants) or by bottle. Six of the infants (Group I) were solely breast-fed before and between the metabolic balance periods. Four infants (Group II) were fed pasteurized human milk before and between the metabolic balance periods during which fresh human milk was fed. The mean intake of nitrogen by the infants fed fresh human milk was less than that of previously studied infants who received pasteurized human milk. Reasons for the smaller mean intakes of nitrogen by infants of Group I may have included voluntary decrease in volume of intake on the part of infants because of time unfamiliar environment or because milk was fed from a bottle. An additional factor may have been decreased supply of milk by the mother (and possibly decreased concentration of nitrogen in the milk) because of altered conditions for nursing and multiple trips to the Metabolism Ward. Decreased concentrations of nitrogen in the milk fed to infants of Group II may have resulted from longer duration of lactation of the women providing the milk and greater volume of milk produced. The relation of retention of nitrogen to intake of nitrogen was the same for infants fed fresh human milk as had been found for those fed pasteurized human milk. Four of the infants (Group II) studied while receiving fresh human milk by bottle were also studied while receiving pasteurized human milk. Intakes and retentions of nitrogen were similar with both feedings. The literature concerning nitrogen balance studies of full-term infants was reviewed. Mean intakes and retentions of nitrogen are similar to those of the present study but considerably greater variability was encountered, as might be expected in view of the lack of uniformity of experimental conditions among the different studies. Processing (pasteurization and freezing) of human milk apparently does not alter its nutritional properties in such a way as to affect nitrogen balance of infants. It is concluded that the retentions of nitrogen of the infants fed processed human milk in the previous study may be considered representative of the retentions of nitrogen by normal breast-fed infants.

A new method of preserving fresh human milk

A new method of preserving fresh human milk

Cell Contents of Milk

BEING interested in the study of the cell contents of milk, I have investigated the colostrum bodies present in fresh human and cow's milk. I devised two methods of studying the milk cells: in wet films, staining the nuclei with methylene blue; and by dry films, staining with May Grunwald Giemsa. The smears were made from fresh milk, at the commencement of lactation, and some smears were made from the cells deposited after centrifuging.

Validity of Human Milk as regards Arakawa's Reaction

The above experiment concerns the milk from only one lactant with a healthy growing infant. The experiment should be extented to more lactants, I admit, but it is very difficult to repeat such a systemmatic experiment with more lactants. From my experiment the following can be stated:_??_ 1. A sample of fresh human milk with such an intensity as _??_*1', _??_** 1'or _??_ *** 2'of Arakawa's reaction will keep the same or almost the same intensity as long as 8 hours, even if left to itself in summer time. Samples of human milk with weaker Arakawa's reactions will begin to show a change of the intensity of reaction from the 5th hour on. 2. If a sample of fresh human milk is kept in an ice box, it will show the same intensity of Arakawa's reaction, even if tested as late as 8 hours after obtaining.