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Objective: To assess the distribution of cord blood insulin in an unselected population, and examine its relation to birthweight centiles., Setting: District General Hospital in Nottinghamshire., Subjects: 209 unselected singleton births., Mean Outcome Measure: Cord blood insulin; cord blood C-peptide; birthweight centiles., Results: Hyperinsulinaemic babies (greater than 97th centile for cord insulin) were found at all birthweight centiles. 15% of high birthweight babies were hyperinsulinaemic. For low birthweight babies, the distribution of cord insulin/C-peptide was skewed indicating a high number of low values. Hypoinsulinaemic babies were present up to the 50th centile for birthweight., Conclusions: Abnormalities of fetal insulinisation may be found in babies of all birthweights.

Insulin binding and the capacity of insulin to stimulate the conversion of glucose to carbon dioxide and lipid, and to activate the protein tyrosine kinase associated with the insulin receptor have been investigated in adipocytes isolated from pregnant and non-pregnant women. Insulin binding and the conversion of glucose to lipid were the same for both groups. However, conversion of glucose to CO2 was higher in the non-pregnant group due to an elevated basal activity, and the increase produced by insulin was similar in both groups. The tyrosine kinase activity of the isolated receptor preparations was higher in the pregnant group due to an increase in the basal non-insulin dependent activity, and the increase produced by insulin was similar in both groups. These findings show the in vitro insulin responsiveness of isolated adipocytes is similar for both groups, and suggests that the in vivo insulin resistance of late pregnancy, as far as adipose tissue is concerned, is not due to any inherent defect in insulin action at the receptor or post-receptor level. In vivo insulin resistance may result from an increased level of circulating insulin antagonists.

While there have been considerable advances in the last several years in the nutritional management of the critically ill, these improvements are not always recognized in intensive care environments. In this paper we describe the development and testing of an expert system, NUTRITIONAL ADVISOR, which would be be an aid in providing nutritional assessment and support of critically ill patients. We discuss various approaches to treating time-varying data in the knowledge base in order to provide a recommended level of nutritional support which varies smoothly from day to day.

A case is presented of a 49-year-old patient who had a pulmonary embolism during ovarian cystectomy. The only evidence of its occurrence was a sudden, marked reduction in arterial oxygen saturation as detected by a pulse oximeter. The diagnosis was confirmed 24 hours later by a chest radiograph and a ventilation perfusion scan. Anticoagulant treatment was instituted.

The site of greatest airway deformation in dog lungs was located during maximum expiratory flow by use of tantalum bronchography, fiberoptic bronchoscopy, and airway pressure measurements. A series of area vs. transmural pressure curves for each of these segments of the airway was produced after stepwise changes in transmural pressure. Measurements of area were made using cinephotography to elucidate the effect of time on airway compliance. The maximum flow rate was calculated using the t = 0.1 s compliance curve of the airway. An equation was derived so that maximum flow (V) could be calculated from the area (A) and transmural pressure (Ptm) of the flow-limiting segment. This equation, V = K-A square root of Ptm, implied that if V were constant then A must vary as Ptm-1/2. It was demonstrated that the area-transmural pressure curve of the flow-limiting segment showed this relationship between A and Ptm and that the flow calculated from this equation and the data from the A-Ptm curve gave flows identical to those measured during maximum expiration. The phenomena of effort-independent flow and negative effort dependence are also explained in terms of the area-transmural pressure curve of the flow-limiting segment.

Twenty-one women completed a longitudinal study of glycosylated haemoglobin in normal pregnancy. Glycosylated haemoglobin levels were measured using two independent techniques (ion-exchange column and colorimetric). Concurrent serial oral glucose tolerance tests (75-g glucose load) and erythrocyte indices were obtained. Changes in mean glycosylated haemoglobin were similar with both techniques with a nadir at 17 weeks, a peak at delivery (p less than 0.002 versus 17 weeks) and a fall post-partum. Glycosylated haemoglobin levels in abnormal pregnancies, e.g. diabetic, should be interpreted in the knowledge of these physiological changes.

A six-year survey of pregnancies complicated by diabetes has been performed at the Kenyatta National Hospital, Nairobi. Fifty-five babies were delivered with 14 perinatal deaths-a perinatal mortality rate of 254/1000, which was five times that of the nondiabetic population. There was one maternal death. Diabetes tended to be of short duration compared with similar series reported from developed countries. There were no perinatal deaths within a small sub-group managed according to a simple plan based on early referral for antenatal care, monitoring of diabetic control by blood glucose, and timing of delivery by use of the "shake test".

The metabolic effects of three diets were investigated in a randomized study in 15 non-pregnant women and 14 pregnant women in the third trimester; all the women were of normal weight. After 2-week periods of habituation to each diet, metabolic profiles were performed on standardized intakes. Diet 1 contained 40% of energy as carbohydrate and 10 g dietary fibre representing typical Western intakes. Diet 2 contained 40% energy as carbohydrate and 52 g dietary fibre and diet 3 contained 60% of energy as carbohydrate and 84 g dietary fibre, representing typical developing world intakes. No deterioration in glucose homeostasis in pregnancy was seen on any of the three diets in contrast to previous work. On diet 1 there was a loss of insulin sensitivity in pregnancy, but not on diets 2 and 3. The loss of insulin sensitivity which is typical of Western women in the third trimester of pregnancy and is considered to be physiological, may be a diet-induced artefact.

A multigas concentration analyzer particularly suited for respiratory gas analysis has been developed using a new principle based on the measurement of the intensity of light emitted by excited atoms or ions in a direct current glow discharge. This glow discharge spectral emission gas analyzer (GDSEA), or light spectrometer, simultaneously measures O2, N2, CO2, He, and N2O gas concentrations with a 0-90% response time of 100 ms and a sample rate of less than 20 ml/min in a short gas sample line configuration. Mole accuracy and resolution of the GDSEA using a short sample line were determined in the laboratory to be +/- 0.15 to +/- 0.7% and 0.02-0.05%, respectively. In the clinical setting a comparative evaluation was made with a mass spectrometer in a long sample line, computerized, multibed, respiratory monitoring system. Results indicate a close agreement between the two instruments with differences in mixed inspiratory or expiratory O2 and CO2 concentrations of less than 2% and of derived variables, such as O2 consumption, CO2 production, and respiratory exchange ratio, of less than 5%.

Autotransplants of pancreas in 8 dogs, with exocrine drainage into the urinary bladder, were stimulated in vivo with cholecystokinin-pancreozymin (CCK-PZ). Transplant biopsies, when compared with 6 normal pancreases, showed normal acinar structure by light and electron microscopy 13-18 months after initial surgery; 2 transplants with sutures unintentionally transecting ducts were fibrosed and had duct obstruction. After in vivo stimulation, the normal-appearing transplants produced a 7-fold increase in urinary amylase, and quantitative electron microscopy showed a 50% reduction in mature zymogen granules; there were no intracellular organelle abnormalities prior or subsequent to stimulation. Fibrosed transplants produced lesser urinary amylase both prior to and after stimulation. In vitro stimulation of grafts with normal structure increased amylase secretion from 1.5-2.1-fold. In vitro dose-response showed a maximum at 10(-9)M cholecystokinin-octopeptide (CCK-OP) in transplant and control. The in vivo stimulation is more responsive and may be useful for clinical monitoring of graft survival. In vivo stimulation occurred after induced urinary tract infection; because no pancreatitis ensued, a regimen of trophic stimulation by CCK-PZ was not contraindicated. The bladder tolerated exocrine drainage with no significant change, and bladder infection did not adversely affect the transplant. The islets appeared normal in the transplants by light and qualitative electron microscopic observation; fasting blood glucose and insulin values were normal during the 12-18-month follow-up. Bladder drainage of segmental grafts of pancreas provides a preparation with intact acinar-islet relationships; the present observations suggest that this may permit longer islet survival in the absence of acinar destruction and subsequent fibrosis.

Objective: To determine whether the high rate of forceps delivery associated with the use of epidural analgesia could be reduced through giving an intravenous infusion of oxytocin during the second stage of labour., Design: A randomised, double blind, placebo controlled trial., Setting: Delivery suites in three hospitals., Subjects: 226 Primiparous women with adequate epidural analgesia in whom full dilatation of the cervix had been achieved without prior stimulation with oxytocin., Intervention: An infusion of oxytocin or placebo starting at the diagnosis of full cervical dilatation at an initial dose rate of 2 mU/min increasing to a maximum of 16 mU/min., Main Outcome Measures: The outcome of labour was assessed in terms of the duration of the second stage, mode of delivery, fetal condition at birth, postpartum blood loss, and the incidence of perineal trauma., Results: Treatment with oxytocin was associated with a shorter second stage (p = 0.01), a reduction in the number of non-rotational forceps deliveries (p = 0.03), and less perineal trauma (p = 0.03) but was not associated with any reduction in the number of rotational forceps deliveries performed for malposition of the occiput. No adverse effects on fetal condition at birth or in the early puerperium were seen in association with the use of oxytocin., Conclusions: The use of an oxytocin infusion may reduce the high rate of operative delivery associated with epidural analgesia provided that the fetal occiput is in an anterior position at the onset of the second stage of labour but within the dose range studied does not seem to correct malposition of the fetal occiput.

Non-obese women in the second half of pregnancy were randomised into a control group receiving standard dietary advice and a group advised to make high fibre whole-food substitutions in their diets at every opportunity. Glucose and insulin profiles were performed over 24-h periods at 29 and 35 weeks gestation when the diets were equivalent in available carbohydrate, protein and fat, but the control group ingested 12.4 g dietary fibre/24 h and the high fibre group 51.4 g/24 h. Glucose homeostasis was similar in both groups but there was a significant attenuation of post-prandial insulin secretion in the high fibre group. It is suggested that the characteristic post-prandial peaks of plasma insulin observed in Western pregnant women are an unphysiological response to dietary fibre depletion.

Screening and selection of hybrids producing relevant antibodies in monoclonal technology usually rely on rapid and sensitive adsorption assays of the ELISA type. To identify clones producing antibodies with unexpected specificities direct immunohistological screening may be applied, but this is both tedious and expensive. Histocomposites made from a number of tissue types permit testing of supernatants at the required early stage after fusion. The multiple antigenic specificities displayed in such test specimens ensure detection of a broad range of antibodies. A simple method for production of the histocomposites is described.