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Pit-1, a member of the POU-homeo domain protein family, is one of the transcription factors responsible for anterior pituitary development and pituitary-specific gene expression. Here, we describe seven children with GH, PRL, and TSH deficiency from three, reportedly unrelated, Middle Eastern families, harboring a newly recognized Pro- > Ser recessive mutation in codon 239 of the Pit-1 gene. The mutated residue is located at the beginning of the second alpha-helix of the POU-homeodomain and is strictly conserved among all POU proteins. The Pro239Ser mutant binds DNA normally but is unable to stimulate transcription.

Fanconi anemia (FA) is an autosomal recessive disorder associated with hypersensitivity to DNA cross-linking agents and bone marrow failure. At least four complementation groups have been defined, and the FA group C gene (FAC) has been cloned. We have screened 76 unrelated FA patients of diverse ethnic and geographic origins and from unknown complementation groups for mutations in the FAC gene either by chemical cleavage mismatch analysis or by single-strand conformational polymorphism (SSCP). Five mutations were detected in four patients (5.3%), including two novel mutations (W22X and L496R). Nine polymorphisms were detected, seven of which have not been described previously (663A-->G, L190F, IVS6 + 30C-->T, I312V, V449M, Q465R, and 1974G-->A). Six of the nine polymorphisms occurred in patients or controls from the Tswana or Sotho chiefdoms of South Africa and were not found in 50 unrelated European controls. Restriction site assays were established for all 8 pathogenic mutations identified in the FAC gene to date and used to screen a total of 94 unrelated FA patients. This identified only one other group C patient, who was homozygons for the mutation IVS4 + 4A-->T. This study indicates that the proportion of FA patients from complementation group C is generally likely to be less than 10%. Guidelines for the selection of FA patients for FAC mutation screening are proposed.

Two families with familial isolated GH deficiency (IGHD) were studied, type II (autosomal dominant) and type I (autosomal recessive), whose GH1 genes exhibit cosegregation with IGHD. DNA sequencing of the GH1 genes of the first family (IGHD II) demonstrated heterozygosity for a T-->C transition in the sixth base of the donor splice site of intron III. The GH1 gene mutation in the second family (IGHD I) was found, in a previous study, to be a G-->C transversion altering the first base of the donor splice site of intron IV. Interestingly, analysis of the transcripts derived from the mutant IGHD II allele revealed that the sequences corresponding to exon III were absent due to an exon skip that causes the loss of amino acids 32-71 from the mature GH protein. In contrast, the IGHD I mutation activates a cryptic donor splice site 73 bases upstream of the normal exon IV donor splice site causing loss of amino acids 103-126 of exon IV followed by a reading frameshift and synthesis of 94 novel amino acids before chain termination 88 nucleotides downstream of the normal GH stop codon. It is hypothesized that, because of the loss of protein sequences derived from exons IV and V, the IGHD I mutation products are not transported to secretory granules and thus cannot perturb secretion of the normal monomeric GH protein. In contrast the T-->C IGHD II mutant allele product retains these sequences and is transported to secretory granules where it can interact with the normal allele product producing a dominant-negative effect at the protein level.

Fanconi anaemia is an autosomal recessive disorder associated with increased chromosome breakage and progressive bone marrow failure. The gene for complementation group C (FACC) has been cloned and mapped to chromosome 9q22.3, but neither its genetic location nor the proportion of patients belonging to group C is known. We have used a polymorphism within the FACC gene to localise it within a 5 cM interval on chromosome 9q, bounded by D9S196/D9S197 and D9S176. The genes for Gorlin's syndrome and multiple self-healing squamous epitheliomata have also been mapped to this interval. Linkage analysis with the three highly informative microsatellite polymorphisms flanking FACC in 36 Fanconi anaemia families showed that only 8% of families were linked to this locus. This indicates that the genes for the other Fanconi anaemia complementation groups must map to one or more different chromosomal locations. The markers also allowed rapid exclusion of 56% of the families in our panel from complementation group C, thus substantially reducing the number of patients who need to be screened for FACC mutations.

Eight different mutations were detected in the growth hormone (GH) receptor gene of patients with inherited GH receptor deficiency (GHRD; Laron syndrome) from five continents. All the mutations are located in the extracellular domain of the receptor and are predicted to cause gross structural abnormalities and non-functional receptor molecules. They include three nucleotide changes in the coding region causing translational stop signals, including the newly identified E183X mutation; two nucleotide changes in introns that affect splice junctions; two dinucleotide deletions that result in stop codons downstream; and one single nucleotide change that activates a donor splice site within an exon and results in a transcript missing 24 nucleotides. This latter mutation (E180splice) was first identified in a cohort of patients with GHRD from southern Ecuador. Based on the fact that the E180splice mutation generates a new cleavage site for the restriction enzyme MnlI, a simple diagnostic test has been developed that can be carried out on dried blood spots collected on filter paper. A total of 55 affected individuals from Ecuador has been found to be homozygous for this mutation. Asymptomatic carriers can also be detected, and 104 of 150 individuals screened were found to be carriers. Using this test, the E180splice mutation has recently been detected in one of two oriental Jewish patients from Israel.

The GH1 genes of probands of two families with familial isolated GH deficiency (IGHD) were sequenced. Double stranded sequencing of the polymerase chain reaction (PCR) amplification products from genomic DNA of two affected cousins in a consanguineous Turkish family revealed a G-->A transition in the 20th codon of the GH1 signal peptide. This substitution converts a TGG (Trp) to a TAG (stop) codon and generates a new AluI recognition site. PCR amplification of the GH1 alleles of family members, followed by AluI digestion, revealed that the G-->A transition segregated with the IGHD phenotype. In a Saudi Arabian family, a G-->C transversion was found that alters the first base of the donor splice site of intron IV. This substitution should perturb mRNA splicing, resulting in an altered protein product which should be unstable or bioinactive. This transversion also destroys an HphI site, which was used to assay samples from relatives. Digestion of PCR amplification products with HphI demonstrated cosegregation of the G-->C transversion with IGHD. These results demonstrate that familial IGHD is a heterogeneous disease that perturbs different steps in the expression of the GH1 gene.

A family in which three siblings born to related parents all manifested clinical abnormalities characteristic of Fanconi's anaemia (microcephaly, short stature, slow growth, beak nose, micrognathia, skin dyspigmentation and forearm and thumb dysplasia in 2/3) is reported. All five family members had normal spontaneous chromosome breakage, a normal response to diepoxybutane and mitomycin C, and were fully informative for linkage with four DNA markers from chromosome 20q12-13.3 with no evidence for linkage. It is concluded that abnormalities typical for Fanconi's anaemia are inherited as an autosomal recessive without the defect responsible for increased chromosomal fragility and independently from the genes so far identified as being responsible for Fanconi's anaemia.

Unlabelled: OBJECTIVE, PATIENTS AND DESIGN: X-linked hypophosphataemic rickets (HYP) is the most common inherited form of rickets and the gene causing this disorder has been localized to Xp22.3-p21.3 by linkage studies of affected families of Northern European origin. In addition, the locus order Xpter-(DXS207-DXS43,DXS197)-HYP-DXS41-X cen has been established and the flanking markers are useful for the presymptomatic diagnosis of HYP. However, a recent study indicates locus heterogeneity and this may hinder the use of the flanking markers for presymptomatic diagnosis in additional families and in particular those from different populations. We have therefore investigated one Saudi-Arabian family (13 affected and six unaffected members) with hypophosphataemic rickets for linkage to these and other X-linked markers. A total of 17 cloned human X chromosome sequences identifying restriction fragment length polymorphisms were used to localize the mutant gene causing this disorder in the Saudi Arabian family., Results: Nine (four from Xp and five from Xq) of the 17 X-linked DNA probes proved informative and linkage was established between HYP and the DSX41 locus, peak LOD score = 4.22 (recombination fraction, theta = 0.00). A positive peak LOD score of 2.32 (theta = 0.05) was also obtained between HYP and the DXS207 locus. Thus, the HYP gene in this Saudi Arabian family is linked to two of the four flanking markers which demonstrated linkage in families of Northern European origin., Conclusion: We conclude that the X-linked hypophosphataemic rickets gene in a Saudi Arabian family is located in the Xp22.3-p21.3, a region where this gene has previously been mapped by linkage studies of families of Northern European origin. Our studies have not demonstrated locus heterogeneity, so the flanking markers for HYP previously established in the families of Northern-European origin will be useful in the genetic counselling and presymptomatic diagnosis of this disorder in the Saudi Arabian family.

Objective: To determine the cause of death and incidence of neoplasia in patients treated with human pituitary growth hormone., Design: A long term cohort study established to receive details of death certification and tumour registrations through the Office of Population Censuses and Surveys and NHS central register., Patients: All patients (1246 male, 662 female) treated for short stature with pituitary growth hormone under the Medical Research Council working party and health services human growth hormone committee., Main Outcome Measures: Death or development of neoplasia., Results: 110 patients died (68 male, 42 female; aged 0.9-57 years) from 1972 to 1990. Fifty three death were from neoplasia responsible for growth hormone deficiency (27 craniopharyngioma, 24 other intracranial tumour, two leukaemia); two from histiocytosis X; and 13 from pituitary insufficiency. Six patients died of Creutzfeldt-Jakob disease, six of other neurological disorders, and eight of acute infection. Other deaths were apparently unrelated to growth hormone deficiency or its treatment. Seventeen tumours (in 16 patients) were identified during or after growth hormone treatment. Four were in patients with previous intracranial neoplasia and two were after cranial irradiation. Thirteen were intracranial, the others being Hodgkin's lymphoma, osteosarcoma, carcinoma of colon, and basal cell carcinoma., Conclusions: Recurrence or progression of intracranial tumours and potentially avoidable metabolic consequences of hypopituitarism were the main causes of death. Growth hormone treatment probably did not contribute to new tumour development. Creutzfeldt-Jakob disease after pituitary growth hormone treatment continues to occur in the United Kingdom. This cohort must remain under long term review.

Twelve infants (six boys, six girls) with severe hypocalcaemic tetany or convulsions were seen over a three year period. Nine patients were symptomatic in the newborn period. Their hypocalcaemia was associated with hyperphosphataemia and very low concentrations of immunoreactive parathyroid hormone. None of the babies suffered from congenital cardiac disease. Cell mediated immunity, measured in five patients, was normal. There were no chromosomal abnormalities but all patients shared several dysmorphic features including deep set eyes, microcephaly, thin lips, beaked nose tip, external ear anomalies, micrognathia, and depressed nasal bridge. Mental retardation of varying degree was found in all patients. All had severe intrauterine and postnatal growth retardation. Four patients have died. The remaining eight patients are on treatments with vitamin D and calcium supplements with no change in their growth pattern. We believe that this association of congenital hypoparathyroidism with severe growth failure and dysmorphism represents a new syndrome.

Rats subjected to temporary protein-energy malnutrition and subsequent nutritional rehabilitation remain smaller than adequately fed animals, have a subnormal insulin secretion and persisting cellular hypoplasia in several tissues. This investigation studies whether impaired production of insulin-like growth factor I (IGF I) is another persisting consequence of malnutrition. Rats were subjected to severe protein-energy malnutrition between 3 and 6 weeks of age and subsequently fed adequate diet up to 12 weeks of age. Serum and tissue samples for analysis of IGF I were obtained at 12 weeks of age. IGF I concentrations were similar in serum, heart, liver and lung of previously malnourished and control rats. In the kidneys of previously-malnourished rats the IGF I concentration was twice that of control rats. Results suggest that during protein-energy malnutrition and subsequent nutritional rehabilitation IGF I tissue concentrations are primarily regulated by the prevailing plane of nutrition. It is speculated that the temporary protein-energy malnutrition blunts the cellular capacity for IGF I production and, except in the kidney, prevents increased IGF I tissue concentrations and associated compensatory growth.

The long-term effects on growth, glucose tolerance and insulin secretory response to glucose of temporary malnutrition early in life have been investigated. Rats were weaned onto either normal diet (18% protein), a protein-restricted diet (5% protein) or a diet adequate in protein but restricted in amount to equal the energy intake of protein-restricted rats ("energy restriction"). From 6 weeks of age and onwards all rats were fed normal diet. Body weight gain was inhibited by both protein and energy restriction but growth was resumed when rats were transferred to normal diet. Protein restriction impaired glucose tolerance and blunted insulin secretory response to glucose. Following refeeding glucose tolerance was normalized but insulin secretory response remained impaired at 12 weeks of age. Energy restriction did not initially affect glucose tolerance and insulin secretion. However, after refeeding male energy restricted rats developed a delayed and exaggerated insulin secretory response to glucose without concomitant deterioration of glucose tolerance. It is suggested that temporary protein restriction at a young age impairs pancreatic B-cell function and decreases peripheral sensitivity to insulin. By contrast, temporary energy restriction does not directly affect B-cell function but confers insulin resistance and compensatory increases of the insulin secretory response to glucose later in life. These models of malnutrition offer possibilities to further study long-term effects of early nutritional insults.

Early protein deprivation impairs glucose tolerance and insulin secretion, but the former generally recovers first. We have therefore investigated insulin sensitivity in vivo and in isolated muscle and cultured hepatocytes during protein-energy malnutrition and long-term follow-up in rats. Rats were weaned at 3 weeks onto normal rat chow (N rats) or onto 5% protein diet (LP rats). At 6 w of age LP rats were transferred to N chow. Insulin sensitivity was studied in the three systems at 3, 6, 12 and 24 w. At 6 w LP rats showed a greater and more prolonged fall in serum glucose in response to injected insulin than age--or weight--matched N, but by 12 w the difference was not significant. Similarly, soleus muscle from 6 w LP showed a higher basal rate of glucose transport and responded to a lower insulin dose than N, but there was no difference in sensitivity at 12 w. Hepatocytes from 6 w LP showed higher basal incorporation of glucose into glycogen than N, but insulin sensitivity was not different. Thymidine incorporation into hepatocyte DNA responded to lower insulin doses in 6 w LP than N. There was a decrease in insulin sensitivity with age in all experimental systems. Increased insulin sensitivity during malnutrition was seen in all tissues studied but differences between the two groups were not significant at 12 w and probably do not account for the normal glucose tolerance in the presence of low serum insulin levels previously reported.

We describe a boy who presented at the age of 7 years with short stature due to hypopituitarism. Six months after starting appropriate hormone replacement treatment at the age of 8 he suffered his first generalised convulsion. Further neuroradiological investigation led to the diagnosis of moyamoya syndrome.

Colonisation of cerebrospinal fluid shunts by coagulate-negative staphylococci (Staphylococcus albus) is a serious problem. Because of its possible role in prevention of the condition, the antimicrobial activity of silicone rubber after impregnation with antimicrobial drugs was studied. The method of impregnation used and test methods were found to be important. Formaldehyde-urea condensates gave no activity. Gentamicin sulphate gave activity which was short-lived. Sodium and diethanolamine fusidates and clindamycin hydrochloride gave prolonged activity. A method of impregnation was developed which could be applied to commercially available shunts before use.

Somatomedin activity was determined by porcine cartilage bioassay and somatomedin-C RIA in matched samples of tracheal fluid (TF), amniotic fluid (AF), and cord (CP) and maternal plasma collected during the delivery of normal infants of 36-40 weeks gestation. Somatomedin levels determined by both assay systems were significantly greater in TF than in AF [TF, 0.40 +/- 0.04 (+/- SE) U/ml; AF, 0.20 +/- 0.02 U/ml by bioassay in 11 infants; TF, 0.25 +/- 0.04 U/ml; AF, 0.18 +/- 0.03 U/ml, by RIA in 6 infants; P less than 0.005]. When chromatographed on Bio-Gel P10 at pH 3.5, the major part of the somatomedin immunoreactivity from both TF and CP eluted in the same position as iodinated somatomedin-C (mol wt, 7600). Somatomedin activity recovered after chromatography of TF and CP increased the incorporation of radiothymidine by growth-restricted human fetal fibroblasts in vitro. Maternal plasma contained 2.49 U/ml radioimmunoassayable somatomedin-C, a value higher than that in the nonpregnant adult. The results suggest that the human fetal lung contributes somatomedin to TF and raises the possibility that these peptides are involved in lung growth or maturation.

We investigated the influence of transforming growth factor-beta (TGF-beta) on DNA synthesis in human fetal fibroblasts, as measured by the incorporation of [3H]thymidine and cell replication. In serum-free medium, without additional peptide growth factors, TGF-beta had no action on thymidine incorporation. However, in the presence of 0.1% v/v fetal calf serum, TGF-beta exhibited a bi-functional action on the cells. A dose-dependent stimulation of [3H]thymidine incorporation, and an increase in cell number, occurred with fibroblasts established from fetuses under 50 g body weight, with a maximum stimulation seen at 1.25 ng/ml. For fibroblasts from fetuses of 100 g or greater body weight, TGF-beta caused a dose-related decrease in thymidine uptake with a maximal inhibition at 2.5 ng/ml, and a small decrease in cell number. When DNA synthesis was stimulated by the addition of somatomedin-C/insulin-like growth factor I, epidermal growth factor, or platelet-derived growth factor, their actions were potentiated by the presence of TGF-beta on cells derived from fetuses under 50 g body weight, but inhibited on cells obtained from the larger fetuses weighing more than 100 g. Similar results were found for changes in cell number in response to TGF-beta when stimulated by SM-C/IGF I. The ability of TGF-beta to modulate [3H] thymidine incorporation did not involve a change in the time required for growth-restricted cells to enter the S phase of the replication cycle. These data suggest that TGF-beta may exert either a growth-promoting or growth-inhibiting action on human fetal connective tissues in the presence of other peptide growth factors, which is dependent on fetal age and development.

Pancreatic sections from 21 cases of rhesus disease and 20 control newborn infants of 30--40-wk gestational age were stained by the immunoperoxidase method for insulin, glucagon, somatostatin, and pancreatic polypeptide (PP). The fractional area occupied by each cell type was estimated, taking note of whether the gland contained PP-rich (ventral lobe) or PP-poor islets (dorsal lobe). In the PP-rich part of the pancreas, the volume fraction of all four endocrine cell types was significantly greater in the rhesus cases than in the controls. No difference was found between the two groups in the PP-poor part of the gland. The results show that abnormal development of the PP-rich part of the pancreas occurs in erythroblastosis fetalis. The localization of the changes to one part of the pancreas may explain some of the earlier conflicting reports on this topic.

In this study, the experimental model of Wigglesworth was used to limit the maternal blood supply to the rat fetus and induce intrauterine growth retardation. The associated changes in plasma somatomedin activity, insulin, glucose, and cartilage metabolic activity are reported. The mean body weight (+/- SEM) of 108 fetuses in ligated uterine horns was significantly lower than that of 146 control fetuses (ligated, 2820 +/- 50 mg; control, 3180 +/- 50 mg; p less than 0.001), as was mean nose-tail tip length (ligated, 55.6 +/- 0.4 mm; control, 59.4 +/- 0.3 mm; p less than 0.001) and mean liver weight (ligated, 222 +/- 5 mg; control, 274 +/- 5 mg; p less than 0.001). The uptake of [35S]sulfate by fetal costal cartilage in basal culture medium was significantly lower in growth-retarded fetuses than in controls. Plasma somatomedin activity measured by fetal rat cartilage bioassay was significantly lower in growth-retarded than in control fetuses (p less than 0.001). The growth-retarded fetuses were relatively hypoinsulinemic and hypoglycemic compared to control animals. These studies suggest that nutrient supply may become a limiting factor in the release of insulin and the circulating levels of somatomedin activity in the rat fetus, and hence in its growth.

Plasma amino acid concentrations were measured in six insulin-dependent diabetic women and seven non-diabetic women in early pregnancy while fasting and one hour after a standard meal. Fasting plasma levels of total amino acids and individual amino acids were similar in the two groups, excepting isoleucine, which was raised in the diabetics. One hour post-prandially total amino acid concentrations were similar in the two groups; however, mean concentrations of total branched chain amino acids and mean concentration of the individual amino acids, serine, valine, isoleucine, leucine and tyrosine were elevated in the diabetics. Amino acids are important in early islet development and in insulin secretion from fetal pancreas in vitro. The elevated post-prandial amino acid levels found in pregnant diabetics in early pregnancy may contribute to fetal islet hypertrophy and hyperinsulinaemia.

Changes in the rate of in-vitro degradation of thyrotrophin releasing hormone (TRH) in serum as related to age have been investigated in the rat and man. In rats, no inactivation was found up to the age of 15 days but therafter an age-related increase in inactivation was detected with approximately 75% inactivation in 60 min at 40 days and reaching a maximum of 88-93% inactivation in adult male and female animals. The human serum samples studied (both male and female) showed a similar but less clear-cut pattern of inactivation of TRH compared with that found in the rat. A physiological role for these age-related changes in the degradation of TRH remains to be established but it has been concluded that the changes observed in both rat and man may be associated with growth and development, possibly by facilitating feedback control of thyrotrophin secretion through the degradation of TRH.

The height and age at presentation of 458 children beginning treatment with growth hormone between January 1980 and June 1984 were retrospectively analysed. Three hundred and nine children with isolated growth hormone deficiency had a mean (SD) age of 10 (4.1) years on beginning treatment and a mean (SD) height standard deviation score (SDS) of -3.73 (0.93). One hundred and nine patients with hypothalamopituitary tumours began treatment with growth hormone on average 3.3 years after diagnosis of the tumour and at a mean (SD) height SDS of -2.42 (1.49). In both of these categories the height SDS showed a considerable improvement compared with previous reports. Forty two patients with growth hormone deficiency secondary to cranial irradiation started treatment with growth hormone on average 6.1 years after treatment for their tumours and had a height SDS of -2.45 (1.02) compared with that of -2.45 (0.98) seen in nine similar patients from the United Kingdom starting treatment with growth hormone between 1975 and 1978. Although closer surveillance of short children in the community is leading to earlier diagnosis of growth hormone deficiency, this could possibly be diagnosed earlier if routine screening of height was to be carried out at school entry. In addition, patients who have received cranial irradiation should be regularly measured and investigated when their height velocity becomes subnormal.

The relative release of rat somatomedin-C (SM-C)/insulin-like growth factor I (IGF I) and multiplication-stimulating activity (MSA) immunoreactivity and bioactivity from isolated fetal rat myoblasts was assessed by a partial characterization of the SM peptides present in concentrated myoblast-conditioned culture medium (MCM). The SM bioactivity of MCM, measured by [3H]thymidine or [35S]sulfate uptake by fetal rat cartilage explants, eluted with an apparent size of 50-80K on Sephadex G-200 at pH 7.5, and was associated with SM-C/IGF I immunoreactivity. Chromatography of MCM on Bio-Gel P-10 or Sephadex G-75 at acidic pH resulted in a peak of SM bioactivity associated with both SM-C/IGF I and MSA immunoreactivity in the 6-9K region. SM-binding activity, measured by competition with activated charcoal for [125I]SM-C or MSA, eluted in the void volume. When these fractions were incubated with [125I]SM-C and chromatographed on Sephadex G-200 at neutral pH, a heterogeneous pattern of binding proteins was seen, with a major component of 50-80K. After chromatofocusing of proteins in the 6-9K region from Bio-Gel P-10, three peaks of SM bioactivity were recovered, each associated with SM-C immunoreactivity, with pI values of 8.5, 7.1, and 6.5. Although both the basic and neutral peaks enhanced [3H]thymidine uptake by growth-restricted fetal rat myoblasts in vitro, only the bioactivity of the former could be blocked by incubation with a monoclonal antibody to human SM-C. Both human SM-C/IGF I and MSA purified from Buffalo rat liver cell-conditioned medium enhanced thymidine incorporation by growth-restricted fetal rat myoblasts. The results suggest that unlike reports of other fetal rat tissues, fetal rat myoblasts released approximately equal amounts of rat SM-C/IGF I and MSA during culture. The myoblast-derived SM-C/IGF I was biologically active on the cell type of origin and may play a paracrine role in muscle development.

Serial measurements of crying vital capacity (CVC), expressed as ml/cm chest circumference, were made by reverse plethysmography during the first 2 weeks of life. Clinically normal babies born at term by elective caesarean section had a smaller mean CVC in the first 2 weeks of life compared with clinically normal term babies born vaginally. In contrast, no significant difference was shown between the mean CVC in term babies born vaginally and those born by urgent caesarean section. Clinically normal term babies born by caesarean section (elective and urgent) had a smaller mean percentage rise of CVC in the first 24 hours of life and a significant delayed rise of CVC from 24-48 hours compared with those born vaginally. Clinically normal preterm babies born vaginally had a smaller mean CVC in the first 2 weeks of life compared with term babies born vaginally, and were characterized by a significant rise of CVC from 5-10 days. Babies with hyaline membrane disease (HMD) had a smaller CVC in the first 2 weeks of life compared with clinically normal preterm babies. Babies of various gestational ages with transient tachypnoea (TT) had a smaller mean CVC in the first 2 weeks of life compared with clinically normal term babies, but a similar mean CVC in the first 72 hours of life compared with clinically normal preterm babies. At each postnatal age the mean CVC of babies with HMD was less than the corresponding mean in babies with TT. All babies with TT had a rise in CVC from 24-48 hours, whereas CVC fell in all babies with HMD except one during this period. CVC is a simple, safe, rapid, and noninvasive test of neonatal lung function, and is a valuable aid to other methods of assessing pulmonary function in the neonate with respiratory distress.

A rigorously designed auxological study was carried out to assess the operational characteristics of the knemometer and the value of short term lower leg and height measurements in estimating and predicting rates of linear growth. Measurements were made on 18 normal children monthly for six months and on six normal children weekly for six weeks. Six other children measured weekly underwent tonsillectomy after three weeks to determine the effect of stress on growth. The measurement protocol permitted estimations of both inter- and intraobserver variation. Knemometry is a sensitive, precise, and robust technique that enables accurate measurements to be made of the lower leg by interchangeable observers. The lower leg does not grow smoothly and variations in growth rate seen in both healthy children and children with transient intercurrent stress limit the practical clinical value of knemometry to the measurement of linear growth in the short term.

Twenty nine (1.8%) of a national cohort of 1600 patients with growth hormone deficiency presented before the age of 2 years. Sixteen of the 29 presented before 6 months of age--11 with symptomatic hypoglycaemia, four with failure to thrive, and one with obesity. Hypoglycaemia was persistent and difficult to control until growth hormone treatment was started. Ten of the 11 hypoglycaemic patients had multiple pituitary hormone deficiencies compared with two of the remaining five. Thirteen children presented between 6 months and 2 years of age; 12 had failure to thrive and one had spontaneous hypoglycaemia. Twelve of the 29 were boys and all but one of these had microgenitalia . Growth hormone deficiency should be considered in the differential diagnosis of infants presenting with refractory hypoglycaemia and in boys with failure to thrive and microgenitalia .

Insulin is a potent mitogen for many cell types in vitro. During tissue culture, supraphysiological concentrations of insulin are necessary to promote cell replication in connective or musculoskeletal tissues. Insulin promotes the growth of these cells by binding, with low affinity, to the type I insulin-like growth factor (IGF) receptor, not through the high affinity insulin receptor. In other cell types, such as hepatocytes, embryonal carcinoma cells, or mammary tumor cells, the type I IGF receptor is virtually absent, and insulin stimulates the growth of these cells at physiological concentrations by binding to the high affinity insulin receptor. Both receptor systems activate phosphorylation reactions within the cell which extend to ribosomal proteins. Insulin acts synergistically with other factors, such as platelet-derived growth factor and epidermal growth factor, to stimulate the progression of cells through the cycle of proliferation. Abnormal insulin secretion or action, before or after birth, often is associated with disordered growth suggesting that insulin may function as a growth factor in vivo. Poor growth follows impaired insulin secretion in diabetes mellitus. This is associated with reduced circulating levels of IGF's which may be partly responsible for the growth failure. Insulin has a direct action on release of IGF's from the liver in vitro, but during experimental diabetes there is a reduced number of hepatic somatotropic receptors which could limit the ability of growth hormone to regulate IGF release. Diabetic children, treated conventionally, have normal circulating IGF levels, but both growth rate and serum IGF concentration may increase dramatically when diabetic control is optimized.(ABSTRACT TRUNCATED AT 250 WORDS)

The pattern and composition of weight change in 19 Kenyan children convalescing from measles, while eating a traditional diet at home, was investigated by serial anthropometry. The majority of children gained weight satisfactorily, 9 (47 per cent) quadrupling the reference rates of weight gain during this period, although 4 remained severely underweight throughout the study. The significant mean improvement in nutritional status, estimated by weight/length, was the result of weight gain accompanied by faltering in linear growth. Rapid weight gain was characterized by an early increase in the fat-free weight and a later rise in subcutaneous fat weight, similar to that shown in children recovering from malnutrition. Children who gained weight poorly demonstrated alternate spurts of weight gain and weight loss. Poor weight gain was significantly (P less than 0.05) associated with anorexia and with diarrhoea. Nutritional and metabolic factors influencing the pattern of weight gain and linear growth after infection are discussed.

The specific binding of human placental lactogen (hPL) and human GH (hGH) to particulate cell membranes from human fetal liver and skeletal muscle at 12-19 weeks gestation was examined. Fetal liver and muscle specifically bound [125I]hPL. This binding was inhibited by increasing concentrations of unlabeled hPL (half-maximal concentrations, 2.2 and 3.4 nmol/L, respectively). Scatchard analysis of the hepatic membrane binding revealed curvilinear plots with higher (Kd, 2.2 nmol/L) and lower (Kd, 24 nmol/L) affinity sites, while binding to muscle involved a single receptor class of Kd 5.6 nmol/L. The binding capacities for the two hepatic sites correlated positively with fetal body weight. [125I]hGH specifically bound to liver, but not muscle, with higher (Kd, 1.6 nmol/L) and lower (Kd, 8.6 nmol/L) affinity sites. [125I]PRL bound to hepatic membranes, but was preferentially displaced by hPL or hGH. Between 4 and 500 micrograms/L (mean, 82 micrograms/L, 3.8 nmol/L) hPL were present in fetal plasma. The findings identify distinct hPL receptors in human fetal liver and skeletal muscle and a hepatic hGH receptor in midgestation.

Intraperitoneal transplantation of collagenase-digested, isogeneic, neonatal rat pancreatic tissue successfully reversed streptozotocin-induced diabetes in 77% of recipients. The low serum immunoreactive insulin, hyperglycaemia, glycosuria and weight loss, characteristic of the diabetic animal, were corrected and the reduced activities of hepatic glucokinase and pyruvate kinase, and the low glycogen concentration of the liver of diabetic rats were restored to normal. Forty-three per cent of the successfully transplanted rats became normoglycaemic within 1 month of transplantation whereas 57% took from 1 to 6 months to achieve normoglycaemia and displayed a mild glucose intolerance when subjected to a glucose load. The rats which had not become normoglycaemic 6 months after transplantation showed some amelioration of the diabetic state, as shown by increased serum immunoreactive insulin and hepatic glycogen concentration and a slow weight gain compared with diabetic controls.

HLA typing of 33 families with one or more children suffering from congenital adrenal hyperplasia confirmed that the gene for 21-hydroxylase deficiency is closely associated with the HLA region. Analysis of two families in which recombination of chromosome 6 had occurred indicated that the gene locus is between the A and D loci of the HLA region. The rare allele Bw47 was observed in 18 parents and was always associated with the carrier state for 21-hydroxylase deficiency.

Cellular development of rabbit liver from late fetal life to adulthood was analysed by quantitative histology and chemical techniques. Hepatocytes and non-hepatocytes were described in number and size. Two thirds of the cells in fetal liver are non-hepatocytes but the volume fraction occupied by them is only 18%. Both number and volume fraction fall with advancing development. Hepatocyte cytoplasm doubles in late fetal life, falls in the 1st postnatal week and then increases to a maximum size in the adult. Perinatal changes in hepatocyte size are related to the accumulation and discharge of glycogen and lipid but also include changes in the protein concentration of the cell.

Rat Tamm-Horsfall glycoprotein (THG) was isolated from urine and disaggregated by gel filtration. Purity was confirmed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and autoradiography. Antibodies were raised and used in the development of a specific radioimmunoassay for rat THG. Parallelism could be demonstrated between the standard preparation and urine (diluted to 1:320 with distilled water) and serum (at all dilutions) samples. Recovery of standard added to urine or serum was on average 93% and inter- and intra-assay variation were both below 7%. There was a positive correlation between the mean urinary excretory rate of THG (microgram/24h) and body weight in female rats (p less than 0.001) but not in male rats. Serum THG levels were similar in both sexes and showed a positive correlation with body weight (p less than 0.001; range 43-240 ng/ml). It is concluded that the rat urinary THG excretion rate is similar to that in man and that rat serum also contains a THG-like protein.

Pancreatic specimens from 34 infants of diabetic mothers (IDM) and 32 control infants of gestational ages 26-44 wk were examined histologically using immunocytochemical stains for insulin, glucagon, somatostatin, and pancreatic polypeptide (PP). Each section was divided into PP-rich and PP-poor regions that are thought to be derived from the ventral and dorsal lobes of the gland, respectively. In some of these, the fractional area (%) occupied by positively stained B, A, and PP cells was determined by automatic image analysis, and the area occupied by D cells was determined by conventional point counting. The B cell fractional area was significantly higher in the IDM in both PP-poor and PP-rich areas (P less than 0.02). the fractional area of A cells in PP-poor areas and of PP cells in PP-rich areas was also significantly greater in IDM (P less than 0.02). The total endocrine cell fractional area was significantly greater in IDM in PP-poor but not in PP-rich regions of the pancreas. These results are not compatible with the hypothesis that maternal hyperglycemia results in specific fetal B cell hyperplasia and raise the possibility that hyperplasia of B, A, and PP cells in IDM may result from a variety of stimuli or that one stimulus acts on a pluripotential stem cell.

Blocks of pancreas were obtained from the following cases of errors of amino acid metabolism: eight cystinosis, eight tyrosinosis, five phenylketonuria, three hypermethioninemia, two hyperprolinemia and two maple syrup urine disease. Blocks were also obtained from four cases of homocystinuria and 72 control patients of the same age range who had died from a variety of conditions believed not to affect the pancreas. Sections were cut from each pancreatic block and stained with haematoxylin or for insulin and pancreatic polypeptide (PP) by the immunoperoxidase method. Measurements were performed separately in the PP rich and the PP poor regions of all sections. The fractional surface area of section occupied by insulin stained cells (%) and the cellular density (nuclei/100 microgram2) of each specimen were estimated. The beta cell fractional area in the PP poor region of the experimental cases was plotted against the logarithm of gestational age and compared to a reference grid of the 10th, 50th and 90th centile estimates of the control cases (Fig. 1). The distribution of results from the cases of tyrosinosis, phenylketonuria and cystinosis were skewed positively; four of eight tyrosinosis and three of five phenylketonuria cases lying above the 90th centile (P less than 0.001). The beta cell fractional area of the cystinosis cases was also significantly increased (Table 1, P less than 0.05). The results from the cases dying from maple syrup urine disease, hyperprolinemia, hypermethioninemia or homocystinuria were distributed as might be expected to occur by chance.

Hepatocytes were isolated by gentle collagenase digestion of liver fragments from human fetuses of 8-16 weeks gestation obtained following prostaglandin-induced pregnancy terminations. They were maintained on collagen-coated tissue culture dishes in selective arginine-free medium for up to 72 hr, and the action of hormones and growth factors on DNA synthesis was studied by autoradiography following incubation with 3H-thymidine. The labeling index of hepatocytes was consistently enhanced by 25-250 ng/ml human placental lactogen (HPL), 25-250 ng/ml human growth hormone (HGH), 10-50 ng/ml insulin-like growth factor I/somatomedin-C (IGF I/Sm-C), and 10% dialyzed fetal calf serum, reaching a maximum of three- to four-fold greater than in basal medium alone. Under basal conditions, 30% of hepatocytes stained positively for the presence of IGF peptides using a monoclonal antibody raised against purified human IGF I/Sm-C. Although this proportion did not change following treatment with HGH and HPL, IGF I/Sm-C released by cells into culture medium was considerably increased in the presence of both hormones. Incubation with the SmC 1.2 monoclonal antibody abolished the increase in labeling index in response to IGF I/Sm-C and partially blocked the response to both HPL and HGH. These results indicate that both HPL and HGH stimulate DNA synthesis in human fetal hepatocytes and suggest that this effect is at least partly indirect through the release and paracrine action of IGF I/Sm-C.

We have investigated the ability of glucose, human GH and human placental lactogen (hPL) to alter the content and release of somatomedin C/insulin-like growth factor I (SM-C/IGF-I), and the biosynthesis, content and release of insulin from cultured human fetal pancreas. Fetal pancreatic explants obtained from glands following prostaglandin-induced abortion between 12 and 21 weeks of gestation were maintained in free-floating culture for 3-5 days before the experiments. The explants were then cultured for 3 days in medium containing either 2.7 or 16.7 mmol glucose/l with or without GH (4.5 or 45.5 nmol/l) or hPL (4.6 or 46.5 nmol/l). Serum-free medium from the final 24 h of culture was collected and SM-C/IGF-I and insulin were measured radioimmunologically in both conditioned medium and tissue explants extracted with acid ethanol. Insulin biosynthesis, determined by immunoprecipitation of [3H]leucine incorporated into insulin, was not significantly altered by any experimental variable. Incubation in the presence of 16.7 mmol glucose/l caused an increase of insulin release from explants, but had no consistent action on insulin content, compared with medium containing 2.7 mmol glucose/l. The pancreatic content and release of SM-C/IGF-I were independent of these glucose concentrations. Neither GH nor hPL altered insulin or SM-C/IGF-I content or release in the presence of the lower glucose concentration. At the higher glucose concentration, 45.5 nmol GH/l did not alter insulin release but caused a significant increase in SM-C/IGF-I content.(ABSTRACT TRUNCATED AT 250 WORDS)

A total of 63 patients with hGH deficiency were recruited, of whom 59 are evaluable. Somatrem (Somatonorm), 4 IU three times/week, was given either subcutaneously or intramuscularly. Height velocity increased from a mean of 4.7 +/- 2.1 cm/year before therapy to 8.2 +/- 2.6 cm/year in the 15 patients who have been followed for 1 year. In patients with isolated hGH deficiency height velocity increased similarly to the whole group, but in those with multiple pituitary hormone deficiencies the pretreatment and on-treatment growth velocities were lower. Of four children who had previously received spinal irradiation, three experienced only a small increase in height velocity on Somatonorm treatment; the fourth showed a considerable increase in height velocity. Anti-hGH antibodies were present in about 80% of the children tested after 12 months of treatment, but the titres and binding capacities were low. Anti-ECP antibodies were also detected, but again the titres were low, and 39% of the children tested had anti-ECP antibodies before treatment commenced.

Foetal rat pancreatic rudiments explanted on day 14 of gestation were grown for 6 days in organ culture in medium containing glucose (5.5(1G) or 16.5(3G)mmol/l) and amino acids at the 'physiological' (1AA) or seven times the 'physiological' (7AA) concentration. Cultures were also performed in medium to which zinc sulphate had been added at 10(-7) to 10(-5) mol/l concentration. At the end of the period of culture the diameters of insulin, glucagon and zymogen granule profiles in the rudiments were compared with those in normal 20-day foetal pancreas by quantitative morphology. The beta cell volume, the number of granules per beta cell, the insulin granular volume fraction and the area of insulin granule core and halo were also measured under selected experimental conditions. Zymogen granule profiles were largest in vivo, intermediate in diameter when grown in 1G x 7AA medium and smallest in 1G x 1AA medium. The mean diameter of glucagon granule profiles remained constant for growth in vivo, in 1G x 7AA medium. Insulin granule profiles were largest in 1G x 1AA medium or in 1G x 7AA medium, smallest in 3G x 1AA mdeium and of intermediate diameter in vivo. Amino-acid enrichment increased the diameter of insulin granules and glucose enrichment decreased it. The addition of zinc to the culture medium had no effect on insulin granule diameter. In 1G x 7AA cultures the beta cells were of similar size to those in vivo, but there were 29% fewer insulin granules per cell. The increased size of the insulin granules in 1G x 7AA cultures resulted in the insulin granule volume fraction in 1G x 7AA being 17.6 compared with 10.8% in vivo. Insulin granule cores were made larger by amino-acid enrichment of the culture medium but they were unaffected by glucose. The haloes were larger in 7AA medium and smaller in 3G medium. Glucose and amino-acid enrichment had a significant interaction on halo area, the mean area in 3G x 7AA medium being less than would have been expected from the summation of the effects of the two conditions.