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

Estudo da composicao do selenio no leite de nutrizes adultas de alto e baixo niveis economicos / Study of the composition of the selenium in the milk of wet nurses of high and low economics levels

Foram estudadas as concentracoes de selenio no leite denutrizes adultas de alto e baixo niveis economicos, maes de recem-nascidos determo para a idade gestacional. Para tanto, foram coletadas amostras do colostroe dos leites de transicao e maduro, sempre no periodo da manha e uma hora apos aprimeira mamada. Detectamos que nao ocorreram diferencas significativas entre osdois niveis economicos estudados, a cada momento de coleta. Entretanto, para am-bos os grupos, verificamos queda gradativa das concentracoes de selenio no transcorrer do periodo estudado, sendo que seus valores no colostro foram maiores quenos leites de transicao e maduro cujas medias nao diferiram significativamente quando comparada entre si. Variaveis como idade, paridade, peso corporal e altu-ra nao se correlacionaram com os niveis de selenio.

Gonadotropin-releasing hormone-associated peptide immunoreactivity in bovine colostrum.

Gonadotropin-releasing hormone(GnRH)-associated peptide (GAP) is a 56-amino acid peptide found on the C-terminal of the GnRH (also called luteinizing hormone-releasing hormone) precursor and is assumed to be co-produced with GnRH. The purpose of this report is to demonstrate the presence of GAP immunoreactivity in bovine colostrum. Radioimmunoassay of acidified methanolic extracts demonstrated a concentration of GAP immunoreactivity of approximately 1.5 +/- 0.1 pmol/g dry skim bovine colostrum. Gel filtration (Sephadex G-10) and high-performance liquid chromatography of extracts containing GAP immunoreactivity showed it to be of low molecular weight and a high hydrophobic character. The presence of GAP immunoreactivity in bovine colostrum suggests that the GnRH precursor is synthesized and processed in mammary tissue itself.

[Ribonucleosides in milk: characterization and determination of the concentration profile of these minor components throughout a lactation period]. / Ribonucleoside in Milch: Charakterisierung und Bestimmung des Konzentrationsprofils dieser minoren Komponenten über eine Laktationsperiode.

The ribonucleosides adenosine, cytidine, guanosine, inosine and uridine as well as the modified components N1-methyladenosine and N6-carbamoylthreonyladenosine were characterized and determined quantitatively as minor constituents in raw bovine milk by use of an automated high performance liquid chromatography system. The studies have shown that except for the colostral phase the ribonucleoside levels are constant throughout the whole lactation period. That means, there is a typical ribonucleoside pattern which is assumed to be species-specific.

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.

Lactational variation and relationship to postnatal growth of insulin-like growth factor-I in mammary secretions from genetically diverse sows.

Mammary secretions obtained from four groups of sows at parturition and on days 7, 14 and 21 of lactation were defatted and assayed for total protein and insulin-like growth factor-I (IGF-I). Sows (n = 57) represented two breeds (Landrace and Duroc) and two genetic lines (selected for differences in sow productivity index, SPI) within each breed. Colostrum of Duroc sows was 4-6 fold and 30-60 fold greater in protein (P less than .001) and IGF-I (P less than .001) concentrations, respectively, than the corresponding day 7 milk from these sows. In contrast, the colostrum of Landrace sows was 2-3 fold and 30-50 fold greater in protein (P less than .001) and IGF-I (P less than .001) concentrations, respectively, than the corresponding day 7 milk. The IGF-I content in milk from Duroc sows did not differ among days 7, 14 and 21 of lactation, whereas the IGF-I content of day 7 milk from Landrace sows exceeded those for the corresponding 14 day and 21 day secretion (P less than .05). IGF-I concentration in days 14 and 21 milk was higher in Duroc (P less than .001 respectively) than Landrace sows. No significant differences in total protein or IGF-I content of mammary secretions were observed between the selected and control lines within each breed.(ABSTRACT TRUNCATED AT 250 WORDS)

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.

Carotenoids of human colostrum.

Colostrum, the initial postpartum secretion of the breast, ordinarily has a distinct yellow color due to carotenoids of its fat globules. This pigmentation progressively diminishes as milk production increases during the first week of lactation. Identity of these carotenoids was investigated by means of thin-layer chromatography, high performance liquid chromatography and spectral analysis. Alpha- and beta-carotene, lycopene and beta-cryptoxanthin were revealed as major chromogens. A component corresponding to lutein and/or zeaxanthin was also detected by both chromatographic techniques. Extracts of 23 saponified colostrum samples from 10 donors revealed considerable variation in total carotenoid concentration (0.34-7.57 micrograms/ml of colostrum). Multiparous mothers had greater mean colostrum carotenoid concentrations than did the primiparae, 2.18 +/- 1.94 vs 1.14 +/- 1.32 micrograms/ml, respectively. Seven of the eight primiparous donors' samples had little or no yellow color. These findings imply a difference in carotenoid transport by breasts that have lactated as compared to those that have not. The interrelation of carotenoids, lactation and breast cancer is discussed.

Phosphoglucomutase proteins in human milk

O polimorfismo do loco 4 da fosfoglicomutase foi investigado em uma amostra de colostro obtida de 652 mulheres (60% brancas e 40% negras), coletada 24 a 48 hs. após o parto, em Porto Alegre, Brasil. Uma nova amostra de leite foi obtida de 175 dessas mulheres com cerca de 17 dias de lactaçäo. No colostro observou-se um acentuado desvio no equilíbrio de hardy-Weinberg, havendo em geral um excesso de homozigotos e deficiência de heterozigotos. No leite, no entanto, esse desequilíbrio näo ocorreu. As diferenças entre as duas distribuiçöes säo devidas à detecçäo de padröes nas amostras que näo apresentavam atividade no primeiro período, assim como a variabilidade na ativaçäo enzimática, que pode ocorrer no início da lactaçäo. As frequências gênicas no leite (n = 175) foram: brancos (n = 127) PGM4*1 = 0,20, PGM4*2 = 0,41, PGM4*3 = 0,38, PGM4*4 = 0,01; negróides (n = 48) PGM4*1 = 0,15, PGM4*2 = 0,52, PGM4*3 = 0,32 e PGM4*4 = 0,01

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.

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.

Synthesis and evolution of concentration of beta-lactoglobulin and alpha-lactalbumin from cow and sheep colostrum and milk throughout early lactation.

Synthesis of beta-lactoglobulin and alpha-lactalbumin by explants of ovine mammary gland and evolution of concentration of these proteins in cow and sheep colostrum and milk throughout early lactation have been studied. The evolution of both proteins was similar in cow and sheep species. The highest concentration was found in the first milking (19 and 2 mg/ml for beta-lactoglobulin and alpha-lactalbumin, respectively). Then, levels of beta-lactoglobulin decreased sharply and those of alpha-lactalbumin slowly during the first days of lactation, reaching stable values during the second week postpartum (4 and 1.5 mg/ml). The concentration ratio beta-lactoglobulin/alpha-lactalbumin was four times greater in colostrum than in mature milk. On the other hand, synthesis of these proteins represented about 25-30% of the synthesized total soluble proteins. The synthesis ratio beta-lactoglobulin/alpha-lactalbumin in explants obtained at 12 and 30 hours postpartum was found to be 3.5 and 1.7. These results indicate that the synthesis and secretion of beta-lactoglobulin are comparatively greater than those of alpha-lactalbumin during colostral period, suggesting that beta-lactoglobulin could have some specific function during this period.

The effect of late pregnancy feed allowance on the milk composition of the sow's colostrum and milk.

The composition of colostrum and milk and of sows fed either 3.4 kg or 1.0 kg daily of a conventional sow diet during the last 14 days of gestation was investigated. The fat content of colostrum of the very restrictedly fed sows was higher compared with the standard fed sows. There was a significantly decrease in the crude protein and immunoglobulin contents of colostrum during the first 4 h post farrowing. The milk composition 14 days after farrowing was not affected by the late pregnancy feeding level. The composition of milk was significantly correlated with the 3 week litter weight. The colostrum IgG content was not correlated to the mortality of piglets during the first week post favouring. The content of crude protein and immunoglobulins in the milk was not correlated with the frequency of post weaning diarrhoea.

[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.