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Biomedical subjects

A Prentice

Publications and source records attributed to A Prentice.

At least 181 records · Page 10Linked to original sources
PubMed1989

Breast-milk fatty acids of rural Gambian mothers: effects of diet and maternal parity.

The influence of diet and maternal parity on the fatty acid composition of mature breast milk have been studied in 23 rural Gambian mothers. The subjects' habitual diet was low in fat (16% total energy), groundnuts (peanuts) constituting the principal fat source. The high abundance of oleic and linoleic acids in groundnut fat were reflected in the proportions of these fatty acids in breast milk (47.0 +/- 1.5 and 13.0 +/- 0.3 g/100 g fat, respectively), which were elevated compared with mothers in other African communities. Estimates of daily breast-milk fatty acid secretion indicated that there was little risk of essential fatty acid deficiency in Gambian infants. The proportions of fatty acids synthesized de novo (10:0, 12:0, 14:0) were less than expected from published studies of mothers consuming low-fat diets, averaging 16.8 +/- 1.4 g/100 g fat. As the study was conducted at a time of food shortage and high energy expenditure, it is argued that mobilisation of body fat during negative energy balance increased the availability of long-chain fatty acids to the breast. The proportion of endogenous fatty acids was markedly reduced in the milk of mothers of very high parity (parity 1 = 19.3 +/- 1.6 g/100 g fat; parities 10 + = 11.4 +/- 1.5 g/100 g fat; p less than 0.01). It is hypothesised that this represents an impairment of the ability to synthesise breast-milk fatty acids de novo in these mothers.

Diet↗
PubMed1989

A protocol for the routine measurement of lactate and pyruvate in cord blood.

The influence of the site of sampling and the delay in sample collection on cord blood concentrations of lactate and pyruvate were investigated. A delay in sample collection of greater than 1 min after cord clamping could invalidate the results obtained. Samples from umbilical artery had higher lactate values (mean 3.13 mmol/l) than paired vein samples (mean 2.32 mmol/l) but there were no significant differences in lactate values between different sites sampled within the umbilical vein. A calculation was devised to circumvent the need to take cord blood samples immediately after delivery.

Blood Specimen Collection↗
PubMed1989

Breast-milk IgA and lactoferrin survival in the gastrointestinal tract--a study in rural Gambian children.

The survival of breast-milk secretory-IgA and lactoferrin has been investigated in 23 Gambian children aged 1.5, 3 and 17 months. Endogenous excretion of these immune proteins was measured in 7 weaned 34-month-old children. Defaecation rate was the prime determinant of faecal secretory-IgA and lactoferrin outputs, indicating that partial degradation occurs in the large intestine. Calculations showed that at least 30% of IgA and 2% of lactoferrin ingested from breast-milk must survive in the small intestine. Variations in faecal immune protein outputs were related to differences in intake and defaecation rate and were not affected by age or solid food consumption. The raised faecal outputs of 5 children with diarrhoea were a consequence of their high stool frequencies. IgA disappearance in the large intestine proceeded twice as fast in Gambian breast-fed children as in comparable Cambridge infants, suggesting that differences in gut flora may influence IgA survival. Thus breast-feeding, irrespective of age or additional food, can deliver significant quantities of these antimicrobial proteins to the small intestine but differences in defaecation rate and gut flora may affect their protective potential in the large intestine.

Breast Feeding↗
PubMed1988

Increased energy expenditure in young children with cystic fibrosis.

To investigate the role of energy expenditure in the altered energy balance in cystic fibrosis (CF), total energy expenditure (TEE) was measured by the doubly-labelled water method in 9 clinically well CF infants (body weight 7.3-10.9 kg) without chronic lung disease. CF infants had 25% higher rates of energy expenditure when compared with data derived from measurements of TEE obtained by the same method in 16 healthy infants, matched for age and body weight. Mean TEE (SEM) for CF was 950 (38) kcal, vs 876 (72) kcal for controls matched for age and 758 (46) kcal for controls matched for weight. Although subclinical disease activity cannot be excluded as a determinant of the excess TEE, the possibility of an energy-requiring basic defect is suggested, because further analysis indicated that factors other than body weight, degree of underweight, presence of pancreatic insufficiency, or presence of lung disease were important. Increased TEE may contribute to undernutrition in CF, even in the absence of chronic lung disease.

Body Water↗
PubMed1988

Milk transfer of phenoxymethylpenicillin during puerperal mastitis.

1 The milk excretion of phenoxymethylpenicillin (PMP) was studied from both breasts in patients with mastitis (n = 12) and healthy volunteers (controls, n = 4) to investigate the hypothesis that milk transfer of PMP is higher in mastitic than in non-mastitic breasts. 2 Patients were included according to clinical symptoms of mastitis. Milk (and serum from controls) were sampled 0, 1, 2, 3, 4, 6 and 8 h after a single oral dose of 1320 mg PMP. Penicillin concentrations in milk and serum were measured by an agar diffusion technique. 3 Maximum milk concentrations (Cmax) of PMP in patients were higher (P less than 0.05) in mastitic than in non-mastitic breasts. The latter concentrations were higher (P less than 0.05) than those in breast milk from healthy controls. In milk from the mastitis patients (both breasts) the Cmax was reached after 2 h with a subsequent rapid decline in concentration. In milk from the healthy controls the PMP concentration reached a plateau after 4 h. The area under the milk concentration vs time curve (AUC0-8h) was not different for mastitic vs non-mastitic breast milk in patients nor for mastitic vs control breast milk. This can be explained by higher rates of appearance and disappearance of PMP in the breast milk of mastitis patients compared with healthy controls. In mastitic breast milk there was a moderate (P less than 0.01) increase in sodium and albumin compared with non-mastitic milk. However, milk potassium, glucose and lactose values were within normal limits.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1987

Fetal heart rate monitoring during labour--too frequent intervention, too little benefit?

For many obstetricians and midwives continuous electronic fetal heart rate monitoring during labour has replaced the traditional method of intermittent auscultation. Of the eight prospective randomised controlled trials designed to assess its value in obstetric care, four were concerned with mothers defined as being at high-risk, three with normal or low-risk patients, and the eighth with the total population of a maternity hospital over several months. None suggested any major advantage of continuous fetal heart rate monitoring over intermittent surveillance in terms of neonatal mortality, morbidity, cord blood pH values, or the five minute Apgar score. The rates of caesarean section and forceps delivery were higher in the continuously monitored group. For low-risk mothers there is a good case for a return to the traditional method of intermittent auscultation with its lower false-positive rate, lesser incidence of intervention, and opportunity for greater contact between the maternity care staff and the mother.

Cesarean Section↗
PubMed1987

The nutritional role of breast-milk IgA and lactoferrin.

The nutritional enigma concerning the extent to which breast-milk immune proteins are digested has been investigated by measuring the intakes and faecal outputs of IgA and lactoferrin over 7 days in 10 exclusively breast-fed (BF) and 9 formula-fed (FF) fullterm infants at 6 and 12 weeks post-partum. BF outputs (mg/day) greatly exceeded FF values (p less than 0.001): at 6 weeks secretory-IgA BF = 160 +/- 28, FF = 14 +/- 2, lactoferrin BF = 14 +/- 2, FF = 0.9 +/- 0.1; at 12 weeks secretory-IgA BF = 94 +/- 17, FF = 25 +/- 5, lactoferrin BF = 7 +/- 1, FF = 1 +/- 0.3. Secretory-IgA represented 42% and 27% of BF faecal protein at 6 and 12 weeks compared with 6% for FF infants at both ages. BF secretory-IgA outputs were highly correlated with intakes (r = 0.83, p less than 0.001). IgA and lactoferrin outputs and the presence of faecal secretory-IgA fragments in BF and FF infants were influenced by defaecation rate, suggesting that partial degradation occurred in the large intestine. By 6 weeks post-partum only 1% lactoferrin and 17% secretory-IgA intakes appeared in the faeces and 95% breast-milk protein could be regarded as nutritionally available. The elevated BF outputs of IgA and lactoferrin relative to endogenous excretion suggest, however, that breast-milk may still make a considerable contribution to intestinal defence mechanisms after the neonatal period despite the small proportion of daily intake which escapes digestion. The protective action of IgA and lactoferrin may also depend on their site of degradation and the nature of fragments.

Feces↗
PubMed1987

Breast feeding increases concentrations of IgA in infants' urine.

To investigate the influence of breast feeding on mucosal immunity the concentrations and daily outputs of IgA and lactoferrin in urine were measured in 10 breast fed and 12 infants fed on formula milk at 6 and 12 weeks of age. The concentrations and outputs of secretory IgA in urine were significantly higher in the breast fed group by a factor of three. The secretion of IgA in urine by the breast fed infants was characteristic of the baby and was not related to the intake of IgA from breast milk. Lactoferrin concentrations were similar in the two groups at both ages. In addition to secretory IgA, two thirds of all samples contained proteins with alpha chain but no secretory component antigenic determinants. Breast feeding seems to increase the local production of secretory IgA into the urinary tract during early childhood, thus providing enhanced protection from infection.

Breast Feeding↗
PubMed1987

Impaired growth in infants born to mothers of very high parity.

Anthropometric data are presented on 412 rural Gambian infants measured longitudinally from birth to 18 months of age. Maternal parity was shown to exert a marked influence on growth. Firstborn babies had significantly depressed birthweights (parity 1: 2.79 +/- 0.06 kg, n = 62; parities 2-9: 3.05 +/- 0.09 kg, n = 309; P less than 0.001) but catch-up growth was complete by 3 months. In contrast, children born to mothers of very high parity (10 and above) had average birthweights (2.90 +/- 0.07 kg, n = 41) but early growth was poor. At 3 months their weights, mid-upper arm circumferences and triceps skinfolds were significantly below those of other infants (eg, weight-for-age (% NCHS): parities 10+: 90.3 +/- 2.3 per cent; parities 2-9: 97.4 +/- 2.7 per cent; P less than 0.01). Supine length and head circumference were not affected. After 3-6 months all children experienced severe growth retardation reflected in poor weight, length and head circumference gains. No catch-up growth occurred in the high parity group. Consequently, anthropometric differentials set up by 3 months were maintained throughout infancy (eg, weight-for-age at 12 months: parities 10+: 76.4 +/- 1.9 per cent; parities 2-9: 81.5 +/- 2.6 per cent; P less than 0.01). The relationship between these infant growth patterns and maternal lactational performance is discussed.

Anthropometry↗
PubMed1985

Mastitis in rural Gambian mothers and the protection of the breast by milk antimicrobial factors.

Mastitis was found to be a sizeable clinical problem in a group of lactating Gambian mothers. The mean monthly incidence was 2.6% and repeated episodes of mastitis were common. The role of milk antimicrobial factors in the local defence of the breast against mastitis was investigated by analysis of IgA, IgG, IgM, C3, C4, lactoferrin and lysozyme in the breast milk of 10 mastitis patients. Acute inflammation of the breast was accompanied by the rapid appearance of high concentrations of serum-derived immunoproteins in mastitic milk. Changes in the milk levels of lactose, sodium and transferrin indicated that this was due to a temporary opening of the paracellular pathway. Concentrations of secretory immunoproteins (IgA, lactoferrin and lysozyme) exhibited a delayed response, being elevated one week after the attack of mastitis. The normal milk of mastitis sufferers was significantly deficient in IgA, C3 and lactoferrin when compared with other lactating women suggesting that the former were predisposed to mastitis.

Complement C3↗
PubMed1984

The effect of water abstention on milk synthesis in lactating women.

The effects of dehydration on mechanisms of water balance and milk synthesis were investigated in ten lactating Gambian women who were fasting during Ramadan. Ten non-pregnant, non-lactating women acted as controls. Fasting consisted of total water abstention from 05.00 hours to 19.30 hours and was accompanied by high insensible water losses. Lactating women lost 7.6% of their total body water between 07.00 hours and 19.00 hours. Control subjects lost significantly less. Plasma indices of dehydration (osmolality, sodium, uric acid) showed a greater rise in the lactating women than in the control subjects over the period of fasting. However, the 19.00 hours values remained in the normal range obtained on non-Ramadan days. During Ramadan the lactating women restricted their urinary output to a lesser degree than the controls, and for much of the day their urine was also less concentrated. The lactating women appeared to have adapted by superhydrating themselves overnight. This resulted in very low urine concentrations (osmolality, sodium, urea, creatinine) in morning samples. Urine concentrations approached, but did not exceed, non-Ramadan levels by late afternoon. The daily water turnover of 6.4 litres in the lactating women was 2 litres greater than in the controls. This difference was much greater than that required for milk synthesis (500 ml) and may represent a further protective mechanism. Fasting caused changes in milk osmolality, lactose, sodium and potassium concentrations indicative of a marked disturbance of milk synthesis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1984

Unilateral breast dysfunction in lactating Gambian women.

Approximately 3% of lactating women in a rural Gambian village displayed long-term unilateral breast dysfunction as evidenced by abnormal milk composition and virtual cessation of suckling by the infant. This paper presents case histories of four such women studied over two successive lactations. The average breast-milk output of these women did not differ significantly from the mean value for the remainder of the community, indicating that the non-affected breast was usually able to compensate for the dysfunction. This was confirmed by the fact that the child-rearing record of three of the four women was better than the community average. In two of the women the breast which was dysfunctioning in one lactation reverted completely to normal for the next lactation. It is suggested that in such cases the dysfunction is self-perpetuating and may be alleviated by counselling mothers to persevere with feeding from the affected breast.

Adult↗
PubMed1984

Breast-milk antimicrobial factors of rural Gambian mothers. I. Influence of stage of lactation and maternal plane of nutrition.

The concentrations of IgA, IgG, IgM, C3, C4, lactoferrin, lysozyme and secretory component in the mature breast milk of 152 rural Gambian mothers were measured up to 26 months lactation. The concentrations and daily secretion of all the immunoproteins, except lysozyme, decreased during the first year of lactation, but were well maintained thereafter. The production of lysozyme increased progressively throughout lactation. Compared with 10 mothers in Cambridge, U.K., the daily secretion of IgG, IgM, C3 and C4 was higher in The Gambia, that of IgA and lactoferrin was similar in the two communities, and that of lysozyme and secretory component was lower in The Gambia. A dietary supplement given to 90 Gambian mothers, raised the mean daily energy intake from a maximum of 1650 kcal/day and a hungry-season minimum of 1 200 kcal/day to 2 300 kcal/day throughout the study. The supplement did not enhance the production of breast milk immunoproteins.

Complement C3↗
PubMed1984

Breast-milk antimicrobial factors of rural Gambian mothers. II. Influence of season and prevalence of infection.

The effects of season and variations in the prevalence of infectious disease on the concentrations and daily production of breast-milk immunoproteins were studied in 152 rural Gambian mothers and their children up to 26 months post-partum. IgA, IgG, IgM, C3, C4, lactoferrin, lysozyme and secretory component concentrations and breast-milk volumes were measured longitudinally over a six month period which encompassed dry and rainy seasons. No increase in the production of any immunoprotein was observed at the time of maximum prevalence of serious infectious diseases, especially diarrhoea, in the children. Enhanced secretion of certain immunoproteins was noted in mothers of children aged 9-18 months at the beginning of the rainy season. There was some evidence that this may have been associated with skin sepsis, particularly impetigo, in the children. The production of most immunoproteins fell during the rainy season. This was not the result of declining maternal food intakes as similar decreases were seen for women receiving a dietary supplement.

Bacterial Infections↗
PubMed1983

Determinants of variations in breast milk protective factor concentrations of rural Gambian mothers.

The concentrations of 7 immunoproteins (IgA, IgG, IgM, the complement components C3 and C4, lactoferrin, and lysozyme) in the breast milk of 152 rural west African women were measured as part of a semilongitudinal study to assess their importance in infant health. Each mother maintained a characteristic level of production of immunoproteins relative to other mothers, and the concentration of each immunoprotein within each woman was correlated positively with the others. Parity was the major determinant of ranking and mothers of parity 1 and 2 produced the highest concentrations of immunoproteins. Except for lysozyme, infants' intake of these protective factors decreased in early lactation, but infants aged 1-2 years still received substantial amounts. The daily intakes by Gambian infants were similar to or higher than those of infants in Cambridge, United Kingdom. A marked seasonal increase in infant morbidity was not accompanied by an increase in the concentrations of protective factors in mothers' milk.

Complement System Proteins↗
PubMed1983

Dietary supplementation of lactating Gambian women. I. Effect on breast-milk volume and quality.

In order to test whether lactational capacity can be improved by dietary interventions, a nutritionally balanced supplement was provided under carefully controlled conditions to 130 nursing mothers in Keneba, The Gambia over 12 months. Maternal mean energy intake (+/- s.e.) increased from 1568 +/- 15 kcal/d (6.56 +/- 0.06 MJ/d) to 2291 +/- 14 kcal/d (9.59 +/- 0.06 MJ/d). Protein intake was in excess of the WHO/FAO recommended intake after supplementation and serious deficits of riboflavin, vitamin A, vitamin C and calcium were rectified. The supplement had no effect on breast-milk volume, compared with retrospective controls, at any stage of lactation or in any season of the year. There was no selective effect on women with poor milk outputs. The average milk protein concentration was slightly improved over the entire period of lactation (+ 6.6 per cent, P less than 0.01), but the total energy content was unchanged since an increase in breast-milk fat concentration (+ 7.9 per cent, n.s.) was offset by a decrease in the milk lactose concentration (- 7.6 per cent, P less than 0.01). Breast milk vitamin content was improved for those vitamins for which the supplement provided a significant proportion of the recommended dietary intake.

Adult↗
PubMed1983

Metabolic consequences of fasting during Ramadan in pregnant and lactating women.

In studies in a rural West African village it was observed that all lactating women and 90 per cent of pregnant women fasted throughout the period of Ramadan. The metabolic consequences of this fasting were studied by measuring serum glucose, free fatty acid, triglyceride, beta-hydroxybutyrate, alanine, insulin, glucagon and T3 levels at 0700 h and 1900 h in 22 pregnant, 10 lactating and 10 non-pregnant, non-lactating women. Results were also compared with overnight-fasted values obtained outside Ramadan. Values for the lactating women were not significantly different from the non-pregnant, non-lactating controls despite the additional metabolic stress of lactation. Ramadan-fasted (1900 h) glucose values from women in late pregnancy (3.01 +/- 0.11 mmol/l) were significantly lower than all other groups (P less than 0.01) and were 15 per cent (P less than 0.01) lower than overnight-fasted values from similar subjects. Ramadan-fasted free fatty acid and beta-hydroxybutyrate levels were significantly higher (P less than 0.05) and alanine values were significantly lower (P less than 0.05) in late than in early pregnancy. It is concluded that the phenomenon of 'accelerated starvation' occurs when women in late pregnancy fast during Ramadan. The possible consequences of this failure to maintain glucose homoeostasis are discussed with reference to the poor outcome of the actual pregnancies studied.

3-Hydroxybutyric Acid↗