Pesquisa do Trypanosoma cruzi na secrecao lactea de mulheres acometidas de doenca de Chagas cronica / The search of Trypanosoma cruzi in breast milk secretion from women with chronic Chagas'disease

Entre os mecanismos alternativos de transmissao de parasitose devida ao Trypanosoma cruzi figura a influencia da secrecao lactea, mas ainda e preciso estipular qual o significado dessa veiculacao em termos de saude publica. Como mais uma cooperacao no sentido de ficar melhor conhecido esse assunto, procuramos o protozoario, atraves de pesquisa direta, cultura e inoculacao, no colostro e no leite de 40 mulheres acometidas de doenca de Chagas cronica. Nao evidenciamos o protozoario, talvez so encontravel por intermedio de procedimentos mais eficientes e de casuisticas bem maiores.

Niveles de sodio, potasio, calcio y magnesio en leche materna de un grupo de madres venezolanas / Sodium, potasium, calcium and magnesiun levels in human milk in a venezuelan mothers group

Se determinó el contenido de Na,K,Ca,Mg en leche materna de 36 madres venezolanas, mediante espectrometría de absorción atómica, en función de las variaciones diurnas, variaciones longitudinales y el tiempo de gestación, no encontrádose una correlación significativa en ninguno de los tres casos. Las concentraciones medias encontradas para Ca y Mg caen dentro de los rangos citados en la literatura, no así para los niveles de Na y K cuyas concentraciones resultaron ser significativamente mayores. Finalmente, el análisis de estos metales en fómulas lácteas de uso comercial evidenció desviaciones importantes respecto a las concentraciones rotuladas

Do changes in pattern of breast usage alter the baby's nutrient intake?

Twelve mother/baby pairs took part in a study of the difference in effect of two patterns of breast feeding--either feeding at one breast or at two breasts during a feed. Baseline measures were taken at 4 weeks, and the test patterns of feeding were followed for a week each, in random order. The two patterns of feeding led to differences in milk volume intake and mean feed fat concentration, but not in the baby's net fat intake per 24 h. The results indicate that the breast-fed baby can regulate his fat intake quickly and thus mothers should be encouraged to practice "baby-led" feeding.

Variation in macronutrients in human bank milk: influencing factors and implications for human milk banking.

Protein (P), fat (F), and carbohydrate (C) concentration in expressed human bank milk was determined by infrared analysis of 2,554 samples from 224 mothers. The mean contents of P, F, C, and energy (E, calculated from P, F, and C) were 9.0 g/L, 39.0 g/L, 71.9 g/L, and 696 kcal/L, respectively. There was a large variation in the concentration of energy-yielding macronutrients. The contents of P, F, C, and E in the samples with the highest values (97.5 percentile) were 2.3-, 4.8-, 1.2-, and 2.3-fold, respectively, above the contents in the samples with the lowest values (2.5 percentile). The P content decreased exponentially during the 1st 8 months, followed by an increase during the following months. The F content decreased during the 1st 4 months, followed by an almost linear increase. The possible influence of different maternal characteristics on the macronutrient content of the milk was examined. The main results were as follows: the P and F contents increased slightly with increasing body mass index of the mother, the P content decreased with increasing amounts of milk delivered to the milk bank, and the F content was higher in mothers delivering large amounts of milk. By selecting incoming milk with a high P content, we have developed a "high-protein" milk with a P content of about 12 g/L (true protein) and an E content of about 725 kcal/L. Thus, by continuous monitoring of macronutrient content in human bank milk it is possible to develop a "high-protein" milk with sufficient P and E content to cover the needs of preterm infants with very low birth weights (less than 1,500 g).

A longitudinal study of pyridoxine and zinc supplementation of lactating women.

Forty lactating women were randomly assigned to four treatment groups. Beginning at 1-d postpartum the women in each group received a daily vitamin-mineral supplement for 9 mo. The treatments differed only in the amount of vitamin B-6 (0.5 or 4.0 mg pyridoxine) and zinc (0 or 25 mg) included in the supplements. The 4.0-mg pyridoxine supplements significantly increased plasma total vitamin B-6, plasma pyridoxal phosphate (PLP), and milk total vitamin B-6, thus showing that maternal intake exerts a significant effect on vitamin B-6 concentration in milk. There was no effect of vitamin B-6 intake on plasma, erythrocyte, or milk zinc concentration. The 25-mg zinc supplement also had no effect on plasma, erythrocyte, or milk zinc concentration, suggesting that maternal zinc intake is not a major regulator of milk zinc concentration.

Distribution of B-6 vitamers in human milk during a 24-h period after oral supplementation with different amounts of pyridoxine.

The relative distribution of B-6 vitamers, separated by reverse-phase liquid chromatography, was examined in human milk during a 24-h period after supplementation with 2.5 or 15 mg pyridoxine hydrochloride. Consistently, pyridoxal (PL) was the predominate vitamer and the most responsive to vitamin B-6 intake. During 3-8 h after supplement ingestion, PL, pyridoxal phosphate, and pyridoxamine concentrations were significantly higher than at other times examined. In the first two periods after supplementation, PL as a percentage of total vitamin B-6 was slightly but significantly higher in milk from the group supplemented with 15 mg than from the group supplemented with 2.5 mg. With the exception of PL, the distribution of B-6 vitamers, expressed as percent of total vitamin B-6, was similar for the two supplemented groups at all times examined. Percentage PL of total vitamin B-6 in milk was approximately 25% lower in unsupplemented than in supplemented women.

Plasma and red blood cell fatty acids of low-birth-weight infants fed their mother's expressed breast milk or preterm-infant formula.

The fatty acid composition of plasma phospholipids, red blood cell (RBC) phosphatidylcholine (PC), and phosphatidylethanolamine (PE) was determined for low-birth-weight (LBW) infants when full oral feeding commenced (day 0) and after a further 28 d (day 28). They were fed their mother's expressed breast milk (PTM, n = 9), formula (SCF, n = 16) with 2% 18:3n-3 fatty acids, 20% 18:2n-6 fatty acids, or a combination of SCF and PTM (n = 11). Concentrations of all 20- and 22-carbon n-6 and n-3 fatty acids were similar among the infant groups on days 0 and 28 (mean postnatal age 42 +/- 1.3 d). The results suggest that formula with greater than or equal to 2% 18:3n-3 and a ratio of 18:2n-6 to 18:3n-3 similar to that of human milk may permit incorporation of n-3 fatty acids in LBW infant tissues equivalent to that from human milk.

[Iodine supplementation in the province of Styria]. / Zur Jodversorgung in der Steiermark.

As far back as 1898 the Austrian Nobel price winner Wagner von Jauregg was the first to recommend iodination of salt as prophylaxis against endemic goitre (prevalence 48%) and cretinism (greater than 10%). In 1923 he achieved in a voluntary iodine supplementation of 5 mg KJ/kg table salt, which only lasted for a number of years. It was in 1963 when finally a mandatory iodized salt prophylaxis was introduced at the rate of 10 mg KJ/kg. In this study the effect of 25 years of iodine supplementation is investigated: Endemic cretinism, hypothyroidism, and goitre in newborns disappeared generally and endemic goitre in pupils was significantly reduced. However, due to epidemiological studies at elementary and secondary schools and army recruitment examinations we still found out endemic goitre grade I (according to WHO) mainly in female juveniles. Examinations were done by palpation, ultrasonography and urinary iodine excretion. In the above as well as in the urine of newborns and in mother's milk the iodine content was significantly lower than in iodine rich countries. Consequently a higher iodination of salt at the rate of 20 mg KJ/kg was recommended by the Austrian Society of Nuclear Medicine in 1985. This suggestion was taken up by the Austrian authorities and it will finally be instituted by law in May 1990 for the benefit of coming generations.

Casein and casein subunits in preterm milk, colostrum, and mature human milk.

Human milk proteins have both nutritional and physiological roles for the breast-fed infant. While the biochemistry and developmental patterns for many whey proteins are well known, our knowledge of human casein and its subunits is still limited. We have recently developed a method to isolate casein from whey proteins in human milk and to separate the casein subunits by fast protein liquid chromatography. In this study we have applied this methodology to study the casein subunit pattern in preterm milk, colostrum, and mature milk. Casein concentration increased with lactation time, largely due to an increase in glycosylated forms of casein (kappa-caseins). Thus, the relative proportion of beta-casein to kappa-casein decreased during the lactation period. The patterns of phosphorylated and glycosylated casein subunits were found to vary during lactation, showing that both synthesis and posttranslational modification of beta- and kappa-casein are regulated by different mechanisms.

Pyridoxine supplementation of lactating mothers: relation to maternal nutrition status and vitamin B-6 concentrations in milk.

Vitamin B-6 status, assessed by plasma pyridoxal phosphate (PLP) concentrations, and vitamin B-6 concentrations in breast milk were examined in 47 lactating mothers supplemented with different amounts of pyridoxine.HCl (PN.HCl) during pregnancy and the first 6 mo of lactation. PLP concentrations in cord blood and maternal plasma at 2 d postpartum and vitamin B-6 concentration in colostrum were positively correlated with the amount of PN.HCl supplementation prenatally (r = 0.71, p less than 0.001; r = 0.74, p less than 0.001; and r = 0.78, p less than 0.001, respectively). Correlations between the amounts of PN.HCl supplementation postnatally and plasma PLP concentrations increased with the length of supplementation. Plasma PLP concentrations were also correlated with vitamin B-6 concentrations of milk samples, which were obtained on the same day as plasma. PN.HCl supplements between 2.5 and 4.0 mg/d (2.1-3.4 mg PN equivalents) ensured vitamin B-6 adequacy of the mother and maintained relatively saturated concentrations of vitamin B-6 in breast milk.

Serum myoinositol concentrations in premature infants fed human milk, formula for infants, and parenteral nutrition.

Myoinositol concentration was studied in serum of 65 neonates and their mothers at the time of birth, in samples of various types of feedings for infants, and in serial serum samples of 15 premature infants receiving human milk, formulas for infants, or parenteral nutrition over a 3-wk period. At birth the serum concentration of myoinositol was greater in neonates than in their mothers (108 +/- 10 vs 52 +/- 6 mumol/L, respectively, means +/- SEM, p less than 0.01). In feedings for infants, the concentrations of myoinositol were significantly greater in human milk than in formulas or parenteral nutrition solutions (1840 +/- 451 vs 420 +/- 110 vs 100 +/- 8 mumol/L, respectively, p less than 0.001). Over a 3-wk period the serum concentration of myoinositol increased in infants receiving human milk but not in those receiving formulas or parenteral nutrition. Serum concentrations of myoinositol in neonates are greater than in adults and are directly influenced by myoinositol intake.

The unknown human infant.

What is physiological? It is often difficult to answer this kind of question in the field of human reproduction. That is why we propose to take, as a reference, a population of one hundred infants whose lifestyle is, in many respects, different from the standard Western norm. They were born at home without any drugs, share the mother's bed, were breastfed for more than a year, and so on. This study raises questions such as: --Is the neonatal loss of weight physiological? --What are the physiological sleep-wake patterns of the human infant? --Are the transitional phenomena normal stages of human development? --Why are some infants ill when their mother loses weight?

Purification and properties of parathyroid hormone-related peptide isolated from milk.

The occurrence and properties of PTH-related peptide (PTH-RP) in milk was investigated. PTH-RP was purified to homogeneity from human and bovine milk using heat and acid to precipitate milk proteins followed by ion exchange chromatography and reverse-phase HPLC. The peak of PTH-RP from HPLC was detected using a sensitive bone cell bioassay. A single band of peptide was detected on silver-stained polyacrylamide gels, which migrated as a 20-21-kDa macromolecule. PTH-RP isolated from either human or bovine milk had similar electrophoretic mobilities on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The partially purified bovine PTH-RP stimulated cAMP production in UMR106-01 and OK cell lines and elicited a concentration-dependent inhibition of sodium-dependent phosphate transport in OK cells. Incubation of milk extracts with an anti-PTH antiserum did not affect their bioactivity, whereas an antihuman PTH-RP 1-34 antiserum markedly reduced the cAMP response of UMR106-01 cells to the immunoabsorbed milk extracts. A PTH antagonist, norleu PTH 3-34, blocked the stimulation of cAMP production in UMR106-01 cells treated with milk extracts. PTH-RP immunoreactivity and bioactivity occurred in milk extracts of diverse animals from both eutherian and metatherian (marsupial) species. Porcine colostrum also had immunoreactive PTH-RP, although the levels were lower than the immunoreactive PTH-RP concentrations observed in milk samples collected at 7 and 14 days of lactation. Thus, a 20-21-KDa PTH-RP is secreted into milk where it could play a role in the development of suckling, newborn animals.

Antimicrobial proteins of maternal and cord sera and human milk in relation to maternal nutritional status.

Antimicrobial proteins in maternal and cord sera and sequential samples of human milk were studied in a group of 60 Chinese women to determine the degrees of passive immunity transferred from women of different nutritional status to their infants. Maternal malnutrition was characterized by low values for wt/ht2 and serum total protein and albumin. Maternal immunoglobulin (IgG) concentrations were not significantly different between well- and malnourished groups prepartum but were significantly different postpartum. Mean concentrations of cord IgG and lysozyme from well- and malnourished groups were not statistically different. During the first 7 d of lactation and most stages thereafter, mean concentrations of IgA; complements C3 and C4, and lysozyme in milk from the malnourished group were only half of those of the well-nourished group. Antimicrobial proteins transferred via milk to newborns may be influenced by the mother's nutritional status.

Milk selenium of rural African women: influence of maternal nutrition, parity, and length of lactation.

The selenium content of milk samples from rural Gambian women (n = 55) was evaluated as a function of parity, stage of lactation, and maternal nutrition. Samples were collected during periods of relative food abundance (dry season) and food scarcity (rainy season). Milk selenium was lower (p less than 0.01) in the rainy than in the dry season (208 vs 256 nmol/L, respectively). Milk selenium was similar in samples from women in early (1-6 mo postpartum) and late (13-19 mo postpartum) lactation. During late lactation, parity, which ranged from 1 to 11, was negatively correlated with milk selenium regardless of plane of maternal nutrition (p less than 0.02). Measures of protein, glutathione peroxidase, and total peroxidase were not affected by stage of lactation or parity. Glutathione peroxidase activity accounted for 38% of the peroxidase activity in milk. Results show that although length of lactation alone had little impact, milk selenium secretion was influenced by both maternal nutritional adequacy and parity of rural Gambian women.

Mineral and trace element content of human transitory milk indentified with inductively coupled plasma atomic emission spectrometry.

Mineral and trace element content of the human transitory milk collected on days 6 to 9 postpartum in Tokyo was measured by inductively coupled plasma atomic emission spectrometry (ICP-AES). Ten elements (Na, Mg, P, S, K, Ca, Fe, Cu, Zn, and Sr) were detected in ten-fold diluted milk sample with this method. With the stepwise multiple regression analysis, maternal and infants' biological attributes, such as weight, stature, sex, or age, were noted as factors contributing to the interindividual variation in Na, Mg, P, S, and Sr. Biological mechanism responsible for this selection cannot be found. Days postpartum for the milk collection was selected as a highly significant (p less than 0.001) variable with negative coefficient to explain milk S variation.

[Presence of specific factors in mother's milk against strains of diarrhea-causing Escherichia coli in humans]. / Presencia de factores específicos en leche materna contra cepas de Escherichia coli causantes de diarrea en humanos.

Presence of specific secretory immunoglobulin A (sIgA) against pathogenic factors of Escherichia coli related with diarrheal disease was studied in colostrum and breast-milk samples obtained longitudinally from a cohort of rural Mexican women. Levels of sIgA against heat-labile enterotoxin, Shiga-like toxin, colonization factors antigens I, II and E8775 and adherence to HEp-2 cells were detected in samples obtained from 54 rural women during the first year of lactation. Although production of specific sIgA against these pathogenic factors was almost universal it was not constant, even in the same woman. The results reflect a definite mother-infant relationship during this period. The data support the thesis of using breast-milk as a vaccination vehicle against diarrhea associated with specific organisms during the first year of life of infants born in developing areas of the world.

Breast milk zinc and copper concentrations in Bangladesh.

Breast-fed infants in Bangladeshi villages were weighed at 1, 2, 6, 9 and 12 months. The concentrations of zinc and copper in the breast milk were measured and the daily intake of these elements calculated. Breast milk Zn concentration decreased over the year but was comparable with that found in developed countries. The calculated daily intake decreased from 17.7 to 8.0 mumol (10-30% of recommended dietary allowances (RDA); National Academy of Sciences, 1980). Breast milk Cu concentration also fell over the year and was lower than that reported from developed countries. Calculated daily Cu intake was 1.95-2.63 mumol (RDA 7.81-15.63 mumol). Deficiencies of trace elements may therefore be a problem in poorly nourished communities where breast feeding is continued for several years with only small amounts of additional food. Breast milk may not be adequate as the only source of infant nutrition after the first few months of life in Bangladesh.