Protein C Levels in Infancy and Early Childhood

ABSTRACT. Protein C antigen levels were measured in the plasma of healthy full term infants by electroimmunoassay. During the first three months of life (on day four, at one month, two months and three months of age) protein C antigen levels were compared in breast-fed and bottle-fed infants. None of the two groups of infants received vitamin K at birth. Only at the age of three months there was a significant difference between the groups. Unexpectedly infants, who were breast-fed, had a higher protein C level at three months of age. Levels were also measured in 15 healthy children between one and three years of age. The antigen levels increase with age to reach adult values at about three years of age.     

Prolonged Exclusive Breast-Feeding Results in Low Serum Concentrations of Immunoglobulin G, A and M

ABSTRACT. Serum levels of IgG, IgA and IgM were measured in 198 infants at ages 2, 4, 6, 9 and 12 months. By age 9 months 30 infants were still exclusively breast-fed; their IgG and IgM levels were significantly lower than those of infants weaned early to formula (before age 3.5 months). By 12 months 6 infants were still exclusively breast-fed; their IgA levels were by then also similarly lower. There was no significant difference in the number of infections experienced by these groups of infants. After 2 months on formula feeding, the IgG and IgM levels of the infants who were exclusively breast-fed for 9 months had caught up with the levels of the infants weaned early to formula. Only at 12 months of age prealbumin levels of the exclusively breast-fed infants showed a positive correlation to IgG and IgA levels; no correlation was found between immunoglobulin levels and levels of serum iron and zinc.     

Prolonged exclusive breast-feeding results in low serum concentrations of immunoglobulin G, A and M

Serum levels of IgG, IgA and IgM were measured in 198 infants at ages 2, 4, 6, 9 and 12 months. By age 9 months 30 infants were still exclusively breast-fed; their IgG and IgM levels were significantly lower than those of infants weaned early to formula (before age 3.5 months). By 12 months 6 infants were still exclusively breast-fed; their IgA levels were by then also similarly lower. There was no significant difference in the number of infections experienced by these groups of infants. After 2 months on formula feeding, the IgG and IgM levels of the infants who were exclusively breast-fed for 9 months had caught up with the levels of the infants weaned early to formula. Only at 12 months of age prealbumin levels of the exclusively breast-fed infants showed a positive correlation to IgG and IgA levels; no correlation was found between immunoglobulin levels and levels of serum iron and zinc.     

Mucosal IgA, mucosal cow's milk antibodies, serum cow's milk antibodies and gastrointestinal permeability in infants

We have studied development of the levels of IgA cow's milk (CM) antibodies in the saliva, faeces and serum of 20 term and 20 preterm infants from birth to 8 months. All infants already had IgA in their saliva during the first week of life. The levels peaked at the age of one month, thereafter decreasing in both groups; from the age of three months levels remained stable. Term infants had higher levels than preterm infants, but no differences were found between breastfed and CM-fed infants. Breastfed infants had higher levels of IgA in their faeces than did CM-fed infants; the IgA levels were similar in breast-fed term and preterm infants, being highest at birth, and decreasing thereafter. We also showed rising titers of serum IgA CM antibodies, with higher levels in infants regularly exposed to CM than in breast-fed infants. We sought associations between the magnitude of intestinal permeability to human a-lactalbumin (ALA) measured at the ages of 4-7 days and one month and the levels of IgG antibodies to CM, but no such relation was found.;     

A comparison of secretory antibodies in breast-fed and formula-fed infants over the first six months of life

In the present study salivary IgA, anti-Escherichia coli, anti-beta-lactoglobulin and anti-poliovirus type 1 IgA and IgM in serum and saliva were evaluated longitudinally in 13 breast-fed and 14 formula-fed infants over the first six months of life. Salivary IgA was quantified by electroimmunodiffusion; specific IgA and IgM antibodies were determined in serum and saliva by ELISA. Salivary IgA was significantly lower at age one month in breast-fed compared with formula-fed infants but in breast-fed infants salivary IgA increased with age and was significantly higher at six months than at one month. In both groups of infants, at the age of six months, salivary IgA levels were significantly lower than in adult controls. No significant differences in secretory anti-E. coli were observed between the two groups of infants. Salivary anti-poliovirus IgA and IgM antibodies increased transiently only to disappear in most babies at age six months, while anti-beta lactoglobulin IgA and IgM, present in saliva at all ages, showed a wide scatter. No important differences in specific serum IgA or IgM antibodies were observed either between the groups or at different times within the groups.     

Effects of soy formulas on mineral metabolism in term infants

We studied 40 healthy term infants who received a soy-based formula containing either a single carbohydrate (glucose polymers) or dual carbohydrates (glucose polymers and sucrose). Ten exclusively breast-fed infants served as controls for the first four months of the study. All infants were studied at 2 weeks, 2 months, and 4 months of age for anthropometric development, biochemical values, and bone mineral content. There were no differences among the three groups in weight, length, or head circumference gains. Serum levels of calcium, phosphorus, magnesium, copper, 25-hydroxycholecalciferol, and alkaline phosphatase were also similar. However, at 4 months of age, the breast-fed group had a higher plasma zinc level than both formula-fed groups, and at 2 and 4 months of age, it had higher bone mineral content and bone density.     

Vitamin K deficiency in breast-fed infants at one month of age

PIVKA-II (protein induced by vitamin K absence or antagonist-II) was measured, as an indicator of vitamin K deficiency, in breast-fed infants of approximately 1 month of age. The infants consisted of three different groups: untreated (group 1); those given 5 mg vitamin K once at birth (group 2); and those given 5 mg twice, at birth and at 14 days after birth (group 3). At 1 month of age, the rate of PIVKA-II-positive infants and their PIVKA-II levels were significantly reduced in group 3 as compared with the levels of the other two groups, whereas these parameters were similar between groups 1 and 2. This observation suggested that vitamin K administration once at birth may be unsafe by 1 month of age. An additional administration of vitamin K seemed to be necessary for complete prevention of vitamin K deficiency, causing severe bleeding in breast-fed infants of approximately 1 month of age.     

Protein and energy intake during weaning. III. Effects on plasma amino acids

Preprandial plasma amino acid concentrations were measured at 5 and 6 months of age in 30 healthy term infants who were either breast-fed ad libitum or fed one of two different formulas (1.9 g of protein per 100 ml with a whey:casein ratio of 50:50; 2.9 g of protein per 100 ml with a whey:casein ratio of 20:80) ad libitum, plus the same supplementary food regimen. The mean plasma concentrations of total amino acids and especially total essential amino acids were higher in the formula-fed infants. Those fed formula also had plasma concentrations of methionine, isoleucine, phenylalanine, leucine, valine, threonine, aspartate, proline, lysine, tyrosine, histidine that exceeded plasma concentrations of breast-fed infants by 2 or more standard deviations. Concentrations of arginine, glutamic acid, glutamine, ornithine, serine, cystine did not differ and taurine was higher in the breast-fed infants. The data indicate that formulas in common use today during weaning (4-6 months) provide excessive protein intakes when compared to the breast-fed control infants. A lowering of protein concentration and a further manipulation of the whey:casein ratio is necessary if plasma amino acid patterns similar to those found in breast-fed infants is to be achieved with artificial feeding.     

Protein and Energy Intake during Weaning

ABSTRACT. Preprandial plasma amino acid concentrations were measured at 5 and 6 months of age in 30 healthy term infants who were either breast-fed ad libitum or fed one of two different formulas (1.9 g of protein per 100 ml with a whey: casein ratio of 50:50; 2.9 g of protein per 100 ml with a whey: casein ratio of 20:80) ad libitum, plus the same supplementary food regimen. The mean plasma concentrations of total amino acids and especially total essential amino acids were higher in the formula-fed infants. Those fed formula also had plasma concentrations of methionine, isoleucine, phenylalanine, leucine, valine, threonine, aspartate, proline, lysine, tyrosine, histidine that exceeded plasma concentrations of breast-fed infants by 2 or more standard deviations. Concentrations of arginine, glutamic acid, glutamine, ornithine, serine, cystine did not differ and taurine was higher in the breast-fed infants. The data indicate that formulas in common use today during weaning (4–6 months) provide excessive protein intakes when compared to the breast-fed control infants. A lowering of protein concentration and a further manipulation of the whey: casein ratio is necessary if plasma amino acid patterns similar to those found in breast-fed infants is to be achieved with artificial feeding.     

转乳期婴儿不同喂养方式对其碘营养变化的影响

目的了解母乳喂养婴儿及其乳母碘营养水平;动态观察从1个月月龄至6个月月龄转乳期时不同喂养方式对婴儿碘营养的影响.方法对97名1个月月龄母乳喂养婴儿尿碘水平进行测定,同时检测其乳母乳碘、尿碘水平,比较二者关系;动态观察97名婴儿从出生至6个月月龄,按喂养方式分为母乳、混合、人工喂养三组,分别检测比较其尿碘水平,与1个月月龄时尿碘水平进行自身对照比较.结果 1个月月龄母乳喂养婴儿尿碘中位数为183 μg/L,提示碘营养状态良好,乳母尿碘、乳碘中位数分别为122 μg/L、201 μg/L,前者明显低于后者(P＜0.001);6个月月龄尿碘水平与1个月月龄比较,母乳喂养组较前升高,人工喂养组下降(P均<0.001),混合喂养组无明显变化(P＞0.05),3组间差异有显著意义(P＜0.005),母乳及混合喂养组明显高于人工喂养(P均<0.001),母乳喂养组婴儿尿碘中位数最高.结论母乳喂养儿碘营养状态良好,乳母碘营养不足;转乳期婴儿碘营养呈下降趋势,部分人工喂养婴儿存在碘营养不良.     

The effect of breast-feeding on proliferation by infant lymphocytes in vitro

The effect of breast-feeding on the development of lymphocyte responsiveness in infants has been studied. Peripheral blood mononuclear cells from 15 breast- and 15 bottle-fed infants were obtained sequentially between 6 days and 9 months of age. A number of agents were used to stimulate the cells in vitro and the resulting proliferative responses were compared between the two feeding groups. A hanging drop microculture system using serum-free medium, enabled spontaneous proliferation and proliferative responses to several stimuli (T and B cell mitogens, allogeneic lymphocytes, and antigen) to be studied at a range of cell concentrations and days of culture. Significant age-related differences were found between the responses of cells from the two feeding groups. Spontaneous proliferation and proliferative responses to the T cell mitogen phytohaemagglutinin and the antigen tetanus toxoid were significantly greater in the breast-fed group at the two earliest ages studied (6 days and 6 wk). Responses to mitogens which predominantly affect B cells, such as pokeweed mitogen and Staphylococcus aureus (Cowan), were similar in both feeding groups at this age. In contrast, from 3 to 9 months of age, responses of cells from bottle-fed infants were significantly greater to all stimuli than responses from breast-fed infants. One possible explanation for the higher level of proliferation by cells from newborn breast-fed infants, is that these infants may absorb the cell-growth factors and lymphokines known to be present in human colostrum and milk. These factors may stimulate T cells and/or their precursors in vivo.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effects of feeding regimen on blood glucose levels and plasma concentrations of pancreatic hormones and gut regulatory peptides at 9 months of age: comparison between infants fed with milk formula and infants exclusively breast-fed from birth

Little is known about the development of gut endocrine responses to food intake in infants after the first postnatal month. To examine this question and to ascertain whether the mode of feeding from birth affects postprandial endocrine changes, blood glucose levels and the plasma concentrations of 11 regulatory peptides were measured at 9 months of age before and after a breast feeding in 13 exclusively breast-fed infants and before and after a formula feeding in 7 infants weaned during the first 3 months of life. In the prefeeding concentrations of these substances, no significant differences were found between the two groups, with the possible exception of the plasma concentration of pancreatic polypeptide (p = 0.06). Postprandially, the responses were significantly smaller in the breast-fed infants, whose plasma concentrations of insulin, gastric inhibitory polypeptide, pancreatic polypeptide, and cholecystokinin were lower than in the formula-fed infants. In addition, the overall level of the insulin-glucagon ratio was lower (p = 0.03) in the breast-fed infants. A difference in the opposite direction was observed for plasma gastrin levels. No significant differences appeared between the groups for blood glucose, or plasma glucagon, vasoactive intestinal polypeptide, motilin, enteroglucagon, secretin, or neurotensin concentrations after feeding. It is concluded that at 9 months of age, the gut regulatory responses to milk feeding are of lower magnitude than during the neonatal period, but even at this age the response patterns still depend on the mode of feeding.     

Levels of serum ferritin and total body iron among infants with different feeding regimens

The levels of serum ferritin and total body iron of healthy infants were analyzed to evaluate iron status among infants with different feeding regimens. The results showed that the levels of serum ferritin and total body iron were lower in breast-fed infants than in partially breast-fed or formula-fed infants at late infancy and 18 months of age.     

Whey predominant,whey modified infant formula with protein/energy ratio of 1.8 g/100 kcal: adequate and safe for term infants from birth to four months

BACKGROUND: Protein quality of breast milk is superior to that of formula proteins. To ensure that the protein intake is sufficient, starter formulas with conventional protein composition provide a protein/energy ratio of 2.2-2.5 g per 100 kcal to infants, which is much higher than that supplied with breast milk. Several studies have shown that formula-fed infants have higher plasma or serum urea concentrations than breast-fed infants do. We tested if feeding formulas with improved protein quality and a protein content corresponding to the minimum level that is consistent with international recommendations (1.8 g/100 kcal) allows patients to achieve normal growth and plasma urea concentrations. METHODS: Healthy term infants were enrolled into the study and were either breast-fed or randomly assigned to three formula-fed groups. Formula-fed infants received either a standard formula with a protein/energy ratio of 2.2 g/100 kcal, whereas the two other groups received formulas with a protein/energy ratio of 1.8g/100 kcal differing mainly by their source of protein. Subjects received breast milk or these formulas ad libitum as the sole source of energy from birth to four months of age in a controlled blind design (except for the breast-fed group). Anthropometric measurements (body weight and length) were obtained at birth, at 30, 60, 90, and 120 days. Energy and protein intakes were calculated from three-day dietary records. Blood was collected for biochemical measurements at 30, 60, and 120 days. RESULTS: No differences were found between the four feeding groups for weight- and length-gains or for body mass indices (BMI). No differences in energy intakes between the formula-fed groups could be found, whereas protein intakes were less in infants fed the 1.8 g/100 kcal formulas. Plasma urea levels of the infants fed the 1.8 g/100 kcal formulas were closer to those found in the breast-fed infants. CONCLUSION: Improvement of the amino acid profile permits a whey predominant starter formula with 1.8 g protein per 100 kcal to meet the needs of normal term infants during the first four months of life.     

Does breast feeding influence liver biochemistry?

OBJECTIVE: It is assumed that early feeding can affect liver biochemistry because breast-fed infants have a higher risk of hyperbilirubinemia than formula-fed infants. The authors sought to determine how feeding mode affected liver biochemistry in healthy term infants. METHODS: Healthy term infants were followed up during infancy with a monthly questionnaire about feeding mode. Blood samples were obtained at 2, 6, and 9 months. Liver biochemistry (serum albumin, alkaline phosphatase, lactic dehydrogenase, aspartate aminotransferase [AST], and bilirubin), total insulin-like growth factor 1 (IGF-I), and insulin growth factor binding protein 3 (IGFBP-3) were determined at all ages. RESULTS: Mean AST and bilirubin were significantly higher in breast-fed infants at 2 and 6 months. In addition, mean albumin levels were higher in breast-fed infants at 2 months. Alkaline phosphatase, IGF-I, IGFBP-3, and lactic dehydrogenase levels did not differ between the feeding groups. AST levels did not correlate significantly with bilirubin, albumin, alkaline phosphatase, or lactic dehydrogenase values. There was a strong positive association between AST and IGF-I at 2 months (r = 0.47, P = 0.004). CONCLUSION: Cytomegalovirus infection, vitamin K deficiency, and macromolecular forms of AST could be an explanation for a higher AST level among breast-fed infants. However, no other clinical or paraclinical sign of liver disease was seen, all infants were given oral vitamin K, and the AST did not rise to levels comparable to those seen in individuals with macromolecular AST. The authors speculate the most likely explanation of the elevated AST is induction of hepatocytes by factors in human milk. This is supported by the higher albumin levels in breast-fed infants and the positive association between AST and IGF-I.     

Efficacy of daily and weekly iron supplementation on iron status in exclusively breast-fed infants

Iron deficiency anemia (IDA) remains the most prevalent nutritional deficiency in infants worldwide. The purpose of this study was to determine the efficacy of daily and weekly iron supplementation for 3 months to improve the iron status in 4-month-old, exclusively breast-fed healthy infants. Infants 4 months of age were eligible for the open, randomized controlled trial if their mothers intended to continue exclusive breast-feeding until the infants were 6 months of age. Infants or mothers with iron deficiency (ID) or IDA on admission were excluded. The infants (n = 79) were randomly assigned to three groups, the first group receiving daily (1 mg/kg daily), the second group weekly (7 mg/kg weekly), and the third group no iron supplementation. Anthropometric measurements were taken on admission and at 6 and 7 months of age. Iron status was analyzed on admission and monthly for 3 months. Both hematologic parameters and anthropometric measurements were found to be similar among the three groups during the study period. Seven infants (31.8%) in the control group, six (26.0%) in the daily group, and three (13.6%) in the weekly group developed ID or IDA (P > 0.05). Infants whose mothers had ID or IDA during the study period were more likely to develop ID or IDA independently from iron supplementation. Serum ferritin levels decreased between 4 and 6 months of age in the control and daily groups; the weekly group showed no such decrease. In all groups, the mean levels of serum ferritin were significantly increased from 6 months to 7 months of age during the weaning period. In this study, which had a limited number of cases, weekly or daily iron supplementation was not found to decrease the likelihood of IDA. In conclusion, exclusively breast-fed infants with maternal IDA appeared to be at increased risk of developing IDA.     

Motilin, vasoactive intestinal peptide and gastrin in infantile colic

Intestinal hyperperistalsis is one part of the clinical picture in infantile colic. Three gut hormones involved in the regulation of gut motility; motilin, vasoactive intestinal peptide (VIP) and gastrin, were measured with the RIA method in: 40 infants with infantile colic, (age 2-22 weeks), 42 healthy age-matched infants, 11 children (age 3-36 months) with gastrointestinal disorders, and 20 children (age 3-36 months) with non-gastrointestinal disorder. Basal s-motilin levels were raised in infants with infantile colic (p less than 0.01) and in children with other gastrointestinal disorders (p less than 0.001). Formula-fed infants had higher basal s-motilin levels than the breast-fed infants (p less than 0.05). P-VIP and s-gastrin levels were raised in children with other gastro-intestinal disorders (p less than 0.05), but not in infantile colic. Formula-fed colicky infants had higher s-gastrin levels than the breast-fed colicky infants (p less than 0.05). We suggest that the increased s-motilin level in infantile colic might account in part for the clinical picture of this disorder.     

Antibody Responses to Parenteral and Oral Vaccines Are Impaired by Conventional and Low Protein Formulas as Compared to Breast-feeding

ABSTRACT. The vaccine response to poliovirus, diphtheria and tetanus toxoids in relation to protein intake was studied in infants, either breast-fed or given low (1.1 g/100 ml) or conventional (1.5 g/100 ml) protein formula. Serum, salivá and faeces antibodies were measured by the enzyme-linked immunosorbent assay. Neutralizing poliovirus antibodies were determined. The serum, saliva and faeces antibody responses in the two formula-fed groups of infants did not differ significantly, but for the low protein formula group which had significantly higher serum neutralizing titres to poliovirus after the second vaccine dose than the conventional formula group. However, the breast-fed group had significantly higher antibody levels than the two formula-fed groups together: serum IgG to diphtheria toxoid (p<0.01) and serum neutralization of poliovirus (p<0.001) at 21-40 months of age, saliva secretory IgA to tetanus (p<0.01), diphtheria toxoid (p<0.01) and poliovirus (p<0.05), as well as faecal IgM to tetanus toxoid (p<0.05) and poliovirus (p <0.01 and p <0.05) at 3 and 4 months of age. Breast-fed infants thus showed better serum and secretory responses to peroral and parenteral vaccines than the formula-fed, whether with a conventional or low protein content.     

Role of prolonged breast feeding in infant growth

The growth of 238 healthy full-term infants was followed under a carefully monitored nutritional protocol during the first year of life. The infants were weaned at different ages either to a proprietary infant milk formula or to a home-prepared cow's milk formula. Solid foods were introduced at 3.5 months of age. The 56 infants who were breast-fed for a period of at least 6 months were compared to infants weaned prior to one month of age to one of the two milk regimens. In the breast-fed infants, the weight, weight-for-height-age, and skinfold thickness were similar to values in the proprietary formula-fed infants but were lower than the corresponding values in the cow's milk-fed infants at 6 months of age and subsequently. By using weight-for-height-age as a criterion, no obesity was found among any of the 238 infants, and only 1.7% were considered to be overweight. The results indicate that present recommendations for infant feeding in Finland--including prolonged breast feeding, the use of proprietary milk formulas after weaning, and later introduction of solid foods--prevent overnutrition.     

Adult height and weight of breast-fed and bottle-fed Israeli infants

BACKGROUND: Breast-fed infants grow more slowly than bottle-fed infants. This growth deceleration sometimes alarms health care personnel to the point of considering other forms of nutrition. OBJECTIVES: To evaluate the final adult anthropometric outcome associated with breast or formula feeding during infancy. DESIGN: Height and weight data were collected from eight well-baby clinics representing various ethnic origins, lifestyles, and socioeconomic backgrounds. Children were measured every 1 to 2 months for the first 6 months, every 3 months until 2 years of age, and yearly thereafter, until they reached their final height. Longitudinal data were collected from 1960 healthy children (961 boys). Overall, 613 of the children were breast fed for 1 year and 218 for 6 months. RESULTS: The magnitude of the decline in Z scores of breast-fed vs. bottle-fed infants, between birth and 1 year of age was not as great for height as for weight -0.2 and -0.3 respectively, and disappeared at 2 years of age. The weight for height decreased between birth and the end of the first year in breast-fed children by 0.3 (Z score). Children switched to bottle feeding exhibited a growth spurt. However, there was no difference in the final heights or weights of breast-fed children compared with bottle-fed children 165.3 +/- 6.2 (n = 134) versus 164.9 +/- 6.4 (n = 195) in females, respectively, and 175.3 +/- 6.8 (n = 122) versus 175.8 +/- 7.1 (n = 162) in males, respectively. Adult obesity in this sample population (n = 637) was correlated with maternal obesity. Maternal BMI SD correlated with offspring BMI SD at 18 years of age (r = 0.873, P < 0.001) but not with breast feeding. Adult BMI was similar between the breast-fed and bottle-fed groups. CONCLUSIONS: Despite their slower growth rate, breast-fed children reach the same final height as bottle-fed children. Breast-fed infants should be monitored according to specifically designed growth charts. Obesity in adult life is correlated with factors not related to breast feeding.