Routine immunisation of preterm infants

Fifty one preterm infants (26-36 weeks' gestation) were enrolled in a study of their immunological responses to diphtheria, tetanus, pertussis, and polio antigens eight to 12 weeks after their primary courses had been completed. Samples from 21 infants born at full term were also analysed. Many infants were able to start immunisation at 3 months of age. Premature infants who are immunised as soon as possible after 3 months of age develop adequate antibody responses.

A child with nocturnal croup

The domiciliary management of a four-year-old with suspected croup is difficult. The differential diagnosis ranges from relatively benign viral illnesses to acute epiglottitis and even diphtheria. Complete obstruction can occur with little warning, and the social situation may further complicate arrangements. As it is not possible to admit every patient with such symptoms, clinical judgement is vitally important.

Langerhans cells in delayed skin reactions to inhalant allergens in atopic dermatitis--an electron microscopic study

Langerhans cells at the site of patch tests to inhaled allergens in patients with atopic dermatitis were investigated. Within 24 h the Langerhans cells showed increased cellular activity and became apposed to mononuclear cells. This supports the view that Langerhans cells are involved in antigen presentation in atopic dermatitis.

High arachidonic acid levels in the cord blood of infants of mothers on vegetarian diets

1. Maternal and umbilical cord plasma samples were collected from forty-seven Asian women, twenty-eight life-long vegetarians and seventeen non-vegetarians, during delivery of their babies. The concentrations and fatty acid profiles of the plasma free fatty acid and triacylglycerol fractions were determined. 2. There were no significant differences between the levels of free fatty acid and triacylglycerol in either maternal or cord plasma from vegetarian compared with non-vegetarian Asian women. The fatty acid profiles of the lipid fractions in the two groups were similar. Total plasma free fatty acid levels in the maternal circulation correlated with umbilical cord levels. 3. The levels of linoleic acid in the maternal plasma free fatty acid fraction of the Asian women were much higher than previous reports on mixed populations of European women. In the Asian women arachidonic acid concentrations in both maternal and umbilical circulations were over four times higher than those reported for women unselected for race and diet.

Evaluation of the Nottingham birth scoring system

A case-control study of postneonatal deaths occurring in 1974-1976 in the City of Nottingham, England, revealed that most were attributable to respiratory infections and SIDS, and primarily occurred in wintertime, at home, in the less well-off parts of Nottingham. By means of a step-wise discriminant analysis, 9% of the infant population was identified as a high-risk group in whom 53% of postneonatal deaths could be expected to occur. From January 1, 1978, this group of infants was followed up more intensively by health visitors and general practitioners, who gave advice on the early recognition of respiratory symptoms. Although the postneonatal mortality rate fell from 6.5 per 1,000 live births in 1977 to 5.2 per 1,000 in 1983, it is not possible to show that the rate of improvement was any faster after the introduction of the system. The system was discontinued on March 31, 1985. Birth scoring systems are not recommended; instead, resources should be concentrated on general improvements in services and symptom recognition, and basic research into the causes of SIDS.

The gamete and embryo compatibility of various synthetic polymers

Several popular and well-characterized polymeric materials were evaluated for their biocompatibility toward the cells unique to reproduction. To accomplish these studies, several in vitro tests were developed that evaluated biocompatibility between the polymers and spermatozoa, ova, and embryos. The data indicated significant differences between the materials with respect to their biocompatibility toward sperm motility, the sperm's ability to penetrate zona-free hamster eggs, and the ability of two-cell mouse embryos to divide. Polytetrafluoroethylene (PTFE-Teflon; PTFE, Chemplast Inc., Wayne, NJ), polyethylene glycol (PEG), and polyhydroxyethyl methacrylate (PHEMA) appear to be the most inert of the materials studied. Polyvinyl chloride (PVC; Tygon-Norton, Akron, OH) was found to be the most detrimental material toward gametes and embryos, with gross physiologic and morphologic changes observed in the PVC-exposed cells.

The effect of limit feeding on thermogenesis and thermoregulation in genetically obese (ob/ob) mice during cold exposure

Thermogenesis and thermoregulation in ad-lib-fed and limit-fed lean (+/ob or +/+) and obese (ob/ob) mice during acute cold exposure were studied by measuring oxygen consumption and body temperature. No significant differences in oxygen consumption were found between the lean ad-lib, obese ad-lib- or obese limit-fed groups. The oxygen consumption of the lean-limit-fed group was decreased by 25-30 per cent compared with the other groups. The body temperature of the obese ad-lib-fed group fell at a rate of at least twice that of any other group. The weight, total cytochrome c oxidase activity and protein content of the brown adipose tissue (BAT) of the lean groups was similar, and there appeared to be little difference in cell size or fat content. The BAT of both obese groups showed a several-fold increase in weight, and a 50 per cent increase in total protein, compared with the lean groups. The limit-fed obese group showed a significant increase in cytochrome c oxidase activity compared with all other groups. The BAT cells of both obese groups were much enlarged and contained considerable amounts of fat. These observations indicate that the susceptibility of obese mice to hypothermia is not due to a reduced capacity for thermogenesis, but to a failure to conserve heat. Failure of thermoregulation in obese animals may be due to postural constraints that result in increased heat loss by radiation. The results are discussed in relation to the accredited role of BAT thermogenesis in rodents exposed to the cold.

The nucleotide sequence of the mRNA encoding the fusion protein of measles virus (Edmonston strain): a comparison of fusion proteins from several different paramyxoviruses

Membrane fusion is the primary cytopathic effect observed in cells infected with measles virus. The viral protein responsible for this process has previously been defined as the fusion (F) protein. Fusion is activated by the proteolytic cleavage of a precursor molecule (F0) to yield two disulfide-linked polypeptides (F1 and F2). In this paper the mRNA for the membrane fusion protein has been cloned and the resulting cDNAs were sequenced. A mRNA composed of 2377 nucleotides was found to contain one open reading frame which could potentially code for a protein of 550 amino acids. This corresponding gene product was identified as the fusion protein through use of antibodies directed against a synthetic peptide which was constructed from the deduced amino acid sequence. A long and rather G-C rich 5' terminus was found on the mRNA and this noncoding region may play some role in regulation of protein synthesis at the translational level. Protein sequence data derived from the cDNA clones revealed a highly conserved F1 amino terminus which is characteristic of most paramyxoviruses. Very little amino acid homology (except for the conservation of the F1 terminus and 9 cysteines) was evident when the sequence was compared to other paramyxovirus fusion proteins. However an overall hydrophobic nature was characteristic of all the F proteins and hydrophobicity plots for the fusion proteins of 4 different paramyxoviruses were very similar. Computer analysis was also employed to analyze the secondary structure of the measles virus F protein. Large stretches of alpha helix were characteristic of the regions which purportedly interact with membranes. The functional domains of the F protein and their similarity to those of the influenza hemagglutinin protein are discussed in this communication. We concluded that the distribution of hydrophobic regions capable of spanning biological membranes determines the fusogenic nature of the F protein.

Prevention of postneonatal mortality

Studies of postneonatal mortality in Nottingham between 1974 and 1977 showed a familiar pattern of high death rates in socially deprived parts of the city. A birth scoring system was devised, which identified at birth 9% of infants in whom 53% of postneonatal deaths could be expected to occur From 1 January 1978 this group was identified by midwives and followed up intensively by health visitors. The postneonatal mortality in the city of Nottingham fell from 8.7/1000 live births in 1974 to 3.6/1000 in 1981. It was not possible, however, to show that the rate of improvement after the introduction of the birth scoring system was greater than the trend present before its introduction. The causes of postneonatal death, and their geographical and seasonal distribution, were similar in 1978-81 and 1974-77, despite an absolute fall in numbers. By 1981 the important risk factors were either recorded on the birth notification or known to the health visitor in any case. Although nurse managers and most health visitors have found the scheme useful in other respects--for example, resource allocation--it was considered that these could be achieved without a formal scoring system. Therefore, the birth scoring system was stopped at the end of March 1985. Health visitors are still being encouraged to pay more attention to high risk cases as a part of normal clinical practice.

Children intoxicated by alcohol in Nottingham and Glasgow, 1973-84

The circumstances of ingestion, clinical course, and long term sequelae were examined retrospectively in 143 children (108 boys, 35 girls) admitted with acute alcohol intoxication in Glasgow and Nottingham over the 12 years 1973-84. Fifty three of the children were aged less than 7 years and 90 were aged 7-14. Twelve of the children were hypoglycaemic on arrival at hospital. Trauma related to intoxication occurred in 14 cases, and nine boys became drunk under duress, which in four cases was associated with sexual abuse.

Evaluation of a special low birth weight formula, with and without the use of medium chain triacylglycerols

A special low birth weight formula containing 1.8 g/100 ml of medium chain triacylglycerols (Nenatal) was compared with 'modified' Nenatal (medium chain triacylglycerols (MCT) replaced by long chain triacylglycerols (LCT)) and standard modified baby milk (Cow and Gate Premium). 22 infants of birth weight less than 1500 g and gestational age less than 33 weeks were studied for three weeks when enteral feeds were well tolerated. Nenatal was given to all infants for the first and third weeks, during the middle week 11 infants received Premium and 11 infants received modified Nenatal. On Nenatal there was a significant elevation of serum beta-hydroxybutyrate and small amounts of medium chain fatty acids were detected in the serum. Glucose and long chain triacylglycerol levels were similar on all feeds. Incremental weight gain and energetic efficiency of weight gain was significantly greater on Nenatal than on Premium, but there was no difference in this respect between Nenatal and modified Nenatal. We conclude that the use of a special low birth weight formula is associated with increased weight gain, but this is not dependent on the presence of MCT in the feed. Therefore although feeds containing MCT are well tolerated, there seems little advantage in including MCT in the formulation of low birth weight feeds.

The preferred environmental temperature of newborn rabbits

The preferred environmental temperature (TE) and rates of oxygen consumption (VO2) around the thermal neutral range were measured in rabbits on the day of birth and 2, 7 and 14 days after birth. On day 0, the preferred TE was 38.0 +/- 0.8 degrees C, and it fell to 30.4 +/- 0.5 degrees C by day 14. Day-0 rabbits kept for 1 h in a warm (41 degrees C), neutral 39 degrees C) or cool (28 degrees C) environment selected a different TE at 39.8, 39.5 and 37.3 degrees C, giving colonic temperatures (TC) of 40.8, 39.9 and 37.7 degrees C, respectively. A similar phenomenon occurred on day 2, but not on day 7. It was concluded that newborn rabbits select a TE to match that which they experienced in utero and that this preferred TE changes after birth depending on the temperature of their surroundings and the development of their thermoregulatory control.

Thermal control in the neonatal unit

The term infant is ready for independent life and responds appropriately in response to changes in environmental conditions by physiological adjustments and giving signals or showing signs to his attendants. Preterms above 32 weeks gestation have a weaker but similar capacity. Infants below 28 weeks gestation have very limited responses and benefit from a strict control of environmental conditions.