Migration, adaptation, and illness: a review.
Explore the source record for details and available documents.
Emotions↗
Biomedical subjects
D Hull
Publications and source records attributed to D Hull.
Water loss from the skin of term and preterm babies.
Water loss from the skin of term and preterm babies, nursed naked in incubators under neutral thermal conditions, was measured by a method based on estimating the water vapour pressure gradient close to the skin surface. 199 sets of measurements were made on 78 babies whose gestational ages ranged from 26 to 41 weeks, during the first 4 weeks of life. Babies of 34 to 41 weeks' gestation had high water losses in the first 4 hours after birth, which then fell to low levels averaging 6 g/m2 per hour. Babies of 30 to 33 weeks' gestation had high water losses in the first week which then fell to levels similar to those of mature babies. Babies less than 30 weeks' gestation had strikingly high losses, averaging 32 g/m2 per hour in the first 4 days of life. At 2 weeks, levels were still higher than those of mature babies. Light-for-dates babies had skin water losses appropriate for their gestations. The high water losses in extremely preterm babies are probably transepidermal and the result of a thin, poorly keratinised stratum corneum. Water loss from the palms and soles was high in term babies and although low in preterm babies it rose steadily in the first 4 weeks of life. This is thought to represent the onset of emotional sweating. In terms of actual heat and water lost, skin water loss is relatively unimportant in term babies nursed naked under neutral thermal conditions. However, in babies less than 30 weeks' gestation, weighing less than 1 kg, skin water loss makes a major contribution to overall water balance. Furthermore, evaporative heat loss from the skin may exceed resting heat production. It is suggested that reduction of skin water loss in these babies may increase their chances of survival and their rates of growth.
Body Water↗
Response of term babies to a warm environment.
The response of healthy term babies to warm environments was assessed by placing them naked in incubators and increasing the air temperature in steps until either sweating occurred or the rectal temperature reached 37.9 degrees C. The rate of evaporation of water from the skin was measured by a method based on the estimation of vapour pressure gradient. When a 50% increase in the rate occurred at a given site, sweating was judged to have begun. 39 studies were made on 30 babies, aged from 4 hours to 11 days. As babies approached the point of sweating, spontaneous activity usually ceased, the skin reddened, and a sunbathing posture was adopted. Sweating was found on 35 occasions. It was most pronounced and often was found initially on the forehead but it was also detected on the trunk and limbs. No thermal sweating was noted on the palms or soles. Sweating generally began when the incubator air temperature exceeded 34 degrees C and the rectal temperature exceeded 37.1 degrees C, but there was wide individual variation. Older and more mature babies tended to sweat at lower air temperatures.
Age Factors↗
The transfer of fatty acids across the sheep placenta.
Maternal and fetal plasma concentrations of free fatty acids, triacylglycerols and phospholipids and the profile of their fatty acids were measured in three catheterized and unanaesthetized sheep. Fetal concentrations of all three lipid fractions were low and did not correlate with maternal concentrations. There were no measurable umbilical venous-arterial differences. Linoleic acid concentrations were low in both mother and fetus. The fatty acid composition of fetal adipose tissue, liver, lung and cerebellum of five animals was analysed. Again linoleic acid levels were very low, but phospholipids contained 2-8% arachidonic acid. [14C] linoleic acid and [3H] palmitic acid were infused intravenously into three ewes. Only trace amounts of labelled fatty acids were found in fetal plasma and these were confined to the free fatty acids. 14C-label was incorporated into fetal tissue lipids, but most of this probably was due to fetal lipid synthesis from [14C] acetate or other water-soluble products of maternal [14C] linoleic acid catabolism. It is concluded that only trace amounts of fatty acids cross the sheep placenta. They are derived mainly from the maternal plasma free fatty acids and might just be sufficient to be the source of the small amounts of essential fatty acids found in the lamb fetus, but are insignificant in terms of energy supply or lipid storage.
Adipose Tissue↗
A postgraduate course in community paediatrics.
Community paediatrics is assuming increasing importance but is rarely taught as an entity. We have recently organized a course in community paediatrics for general practitioners, doctors working in the area child health services and hospital paediatricians. Features of this day release course are self-instruction at home with specially prepared material, discussion between doctors from different disciplines, discussion with non-medical professionals and the undertaking and presentation of a project. The course is flexible, and once set up can be run without extensive facilities and resources.
Child Health Services↗
Cord blood hypertriglyceridaemia as an index of fetal stress: use of a simple screening test and results of further biochemical analysis.
In this preliminary study, 120 cord blood samples were subjected to a simple on-the-ward triglyceride screening procedure and 15 were designated as being high and another 15 randomly selected as controls. All the samples were then subjected to detailed biochemical analysis for fatty acid profiles and/or concentrations of free fatty acids, triglycerides (TG), phospholipids, cholesterol esters and glycerol. Eleven of the samples designated 'high' were associated with one or more of the following clinical conditions: family history of ischaemic heart disease, maternal starvation, fetal distress, light-for-dates babies and excessive weight gain during pregnancy. There was an association between high TG levels and high glycerol levels. The fatty acid pattern of the TG was altered when at abnormally high concentration, in particular oleic acid was increased relative to the others, and this was associated with an increase in cholesterol ester oleic acid. The possible mechanisms resulting in cord hypertriglyceridaemia are discussed.
Cholesterol Esters↗
The passage of fat emulsion across the human placenta.
Six patients near term were given an intravenous infusion of a fat emulsion (Intralipid) a few hours before normal delivery or Caesarean section. Six other non-infused patients were studied as controls. Maternal venous and umbilical venous and arterial blood samples were taken at delivery and analyzed for individual fatty acid concentrations in triglyceride, free fatty acid (FFA) and phospholipid fractions. The emulsion, being rich in oleic and linoleic acids, affected the composition of the maternal triglycerides. The fetal lipids were also altered and the infusions resulted in large positive umbilical venous-arterial (v-a) differences in FFA and triglyceride fatty acid concentrations, but this was not the case for phospholipid concentrations. The fatty acids with the largest v-a differences were those prominent in the emulsion.
Adult↗
Failure to thrive or failure to rear?
The study group comprised 40 unselected Caucasian children admitted to hospital whose ages were between 3 months and 3 years and whose weights were less than 3rd centile. A comparison group comprised 34 children from a similar background whose weights were between the 25th and 75th contiles. The mothers of all 74 children were interviewed and information was obtained on physical health of the child, social and family factors, bonding, feeding difficulties, and maternal childhood experience. In 23 of the 40 underweight children the organic disease was considered to be insufficient to explain the child being underweight and to be probably insufficient in a further 9 children. Three factors occurred more frequently in these 32 underweight children. The mother often perceived herself as having a disturbed mood and used the word "depression" to describe these feelings. She also tended to come from a lower social class than the mother in the comparison group, and her infant frequently had a low birthweight. Identification of these children is not difficult; clinical investigations need to be minimal, and therapy should be directed towards supporting the mother emotionally, improving her relationship with her child, and increasing her mothering skills.
Body Weight↗
Variations in the resting oxygen consumption of small babies.
Over 200 measurements of the resting rate of oxygen consumption using an open-circuit method were made on 15 small babies nursed in their usual clinical setting during the first month of life. There were striking and persistent variations between babies that could not be explained by postnatal age, relationship to feed, sleep, or time of day. It was not possible from clinical examination to predict which babies had the higher or lower metabolic rates, except that babies who were light-for-dates generally had higher values. Because of these variations the appropriate thermal temperature for small babies cannot be predicted from average values adjusted for body weight and postnatal age alone.
Age Factors↗
Metabolic response to cold in the newborn.
Blood concentrations of glycerol and free fatty acids were measured in healthy and sick 5-day-old infants during and after cold exposure. In apparently similar infants in similar circumstances, the blood concentrations varied widely. Although the concentrations of both glycerol and free fatty acids tended to be higher during cold exposure, it is not possible to use either as an index of cold exposure in individual infants.
Blood Glucose↗
Source of fetal-stored lipids during maternal starvation in rabbits.
The effect of 48 h maternal starvation on the composition of fetal rabbit brown and white adipose tissue was examined. Compared with fed control rabbits, adipose tissue triglyceride fatty acids took on a composition more like that of maternal plasma free fatty acids (FFA), whose concentration more than doubled after 48 h starvation. It is concluded that maternal FFA contribution to the fetal lipids increases during starvation and certain fetal acids, in particular linoleic acid, may in the fed state be derived from maternal lipids other than the FFA.
Adipose Tissue↗
Effect of maternal glucose infusions on fatty acid transport across the placenta in rabbits.
Glucose infusions given intravenously to 28-day-pregnant rabbits increased maternal and fetal plasma immunoreactive insulin levels and decreased maternal concentrations of circulating free fatty acid (FFA). Fetal plasma FFA were only slightly depressed and umbilical venous-arterial concentration differences were unchanged both for total FFA and for individual fatty acids in the FFA fraction. The mean umbilical venous concentration was twice that of maternal levels in the infused group, but about the same concentration in untreated rabbits. It is concluded that the infused glucose, or the high insulin levels provoked by it, or both, caused an increased flow of FFA to the fetus, probably from sources other than the maternal plasma FFA.
Animals↗
The transfer of fatty acids across the sheep placenta [proceedings].
Explore the source record for details and available documents.
Animals↗
Why are children admitted to hospital?
The criteria for admitting children to hospital for medical care were examined in 399 consecutive, non-planned admissions to the Nottingham Children's Hospital between October 1975 and January 1976. Sixty-one per cent of the children were referred direct to the casualty department by their parents. Over 20% were admitted primarily for social reasons, and many of the remainder came from homes judged to be at a disadvantage. The hospital medical services for children should be aware of the needs of parents as well as of the needs of sick children in their catchment area.
Age Factors↗
Diurnal plasma free fatty acid profiles in normal and diabetic pregnancies.
Diurnal plasma free fatty acid (FFA) and glucose concentrations were measured in 23 normal women, 13 chemical diabetics, and 11 insulin-dependent diabetics in late pregnancy. The mean diurnal FFA value was lowest in the insulin-requiring diabetics and highest in the chemical diabetics. Although no association was found between percentile birthweight and maternal mean fasting or diurnal FFA, there was a positive correlation between percentile birthweight and both mean maternal fasting plasma glucose and mean diurnal glucose in normal and chemical diabetic women. These observations support the view that glucose is the major substrate used by the fetus, but birthweight may be influenced more by the total substrate crossing the placenta than by maternal levels of either glucose or FFA alone.
Adult↗
Life circumstances and physical illness: a cross disciplinary survey of research content and method for the decade 1965-1975.
Explore the source record for details and available documents.
Humans↗
The transfer of free fatty acids across the rabbit placenta.
1. The passage of fatty acids across the placenta was studied in 28 day pregnant rabbits (i) by comparing the fatty acid distribution in plasma free fatty acids (FFA) of umbilical cord artery and vein with that in maternal plasma and (ii) by infusing the doe at a constant rate with labelled palmitic, linoleic or arachidonic acids. During the infusion maternal and foetal plasma FFA specific activities were measured. 2. The mean levels of all the fatty acids studied (from twelve to twenty carbon atoms) were similar in both the umbilical vein plasma and maternal arterial plasma FFA, except for arachidonic acid, which was higher in foetal blood. The relative distribution of the fatty acids in umbilical arterial plasma similar to that in the vein, but at lower concentrations. The mean cord venous-arterial difference for each fatty acid correlated positively with the mean maternal arterial levels, with the exception of arachidonic acid. 3. During the constant infusion experiments the specific activities of the fatty acids in the maternal and foetal circulating FFA pools rose rapidly during the first 4 min then rose only slowly. Palmitic and linoleic acids were cleared from the maternal circulation in a similar manner and crossed the placenta at similar rates. 4. The average foetal specific activity in plasma FFA reached 15% of the maternal level for both palmitate and linoleate. The figure for arachidonic acid was half that for palmitic acid infused at the same time. 5. It is concluded that (i) all the major fatty acids present in foetal adipose tissue cross the placenta, (ii) the net transport of each fatty acid depends in part on maternal concentrations, (iii) the rate of metabolism of palmitic and linoleic acids is the same and both cross the placenta at the same rate. Proportionately less foetal arachidonic acid is derived from maternal FFA, and (iv) the results suggest a second placental source of arachidonic acid and possibly also of otherfatty acids.
Animals↗