Growth hormone (GH) secretion, GH-dependent gene expression, and sexually dimorphic body growth in young rats with chronic renal failure

Chronic renal disease results in growth failure in children. This study sought to determine the influences of early renal failure on body growth, growth hormone (GH) secretion, and GH-dependent hepatic gene expression. Neonatal animals were subjected to five-sixth nephrectomy (Nephr) and monitored during growth. Sham-operated male (Sham) and female (Fem) rats served as controls. Whereas Nephr of adult animals causes renal insufficiency, neonatal nephrectomy leads to frank renal failure. In male Nephr compared with Sham animals, GH half-life and GH pulse frequency increased by 1.55- and 1.33-fold, respectively, and GH secretory-burst size decreased by 80%. Approximate entropy analysis quantified more disorderly patterns of GH secretion in Nephr animals, which differed from Sham males, but not from Fem rats. Expression of liver P450 CYP2C11 mRNA, which is dependent upon the male GH pattern, became undetectable, whereas expression of liver P450 CYP2C12 mRNA, which is dependent upon the female GH pattern, increased multifold. Renal failure in young rats abrogates the male pattern of GH pulsatility, abolishes the sexual dimorphism of body weight gain, and induces a female pattern of hepatic gene expression. These data raise the possibility that disruption of pulsatile GH secretion contributes to the growth failure of renal disease.     

False-positive Y-microdeletion result for a fertile male caused by an alteration under a PCR primer

The pathogenic relationship between the presence of Y chromosomal microdeletions and male infertility is unclear. Nevertheless, a causal relationship is thought to be probable when loci are shown to be deleted in infertile males but are present in fertile males. Polymerase chain reaction (PCR) analysis of the Y chromosome is now routinely performed in the evaluation of the infertile male, although, until recently, there has been no consensus on how the diagnosis should be performed and which loci or markers should be analysed. The European Academy of Andrology (EAA) published guidelines for the molecular diagnosis of Y chromosomal microdeletions in 1999. Following these guidelines, our laboratory developed assays that incorporated the suggested primer pairs for the recommended Sequence Tagged Sites (STS). A number of fertile (n = 117), infertile (n = 17) and unknown samples (n = 20) were tested in our laboratory as part of the validation to provide a clinical assay. Two multiplex PCR assays were optimized, each of which examined STS markers in the centre of the AZFa, b and c regions of the Y chromosome. We correctly identified all but one of the 154 samples (according to the expected result based on fertility or previous testing at another laboratory). A single equivocal result was observed for a sample obtained from a known fertile male who appeared to be deleted for a single marker, sY84, in the AZFa region but not the adjacent marker, sY86. Follow-up analysis showed that proximal and distal markers within the same region (sY82 and sY98) were also present. Sequencing the region flanking and including the sY84 primer set revealed a single base alteration under the reverse primer, which probably caused the amplification failure. Furthermore, the sY84 sequence itself was present, as was the flanking sequence 50 bp on either side of both primers. This observation underlines the importance of using at least two closely linked STS markers for the reliable diagnosis of Y chromosome microdeletions as proposed by the EAA guidelines.     

Identification of rehabilitation problems after head injury

We have reported a large study of patients admitted to hospital following head injury in the city of Glasgow over one calendar year. This showed 1000 patients still to be disabled one year after their injury. In order to see whether the difficulties reported by these patients represented needs for rehabilitation services, we undertook a parallel study in which a separate group of 26 patients were assessed by the same methods as in the main group, but also had a clinical review by an experienced rehabilitation medicine physician, to determine the patient's rehabilitation needs. The physician was unaware of the results of the first assessment.

Both the extent and the nature of the services as needed were reported remarkably similarly by each form of assessment. In addition, the Glasgow Outcome Scale categories were closely related to the need for services.

We conclude that the data reported by Thornhill et al. can be used to estimate the volume and type of rehabilitation services required by head injured patients in the early months after injury.     

The international collaborative study of maternal phenylketonuria: status report 1994

Neonatal screening for phenylketonuria (PKU) has created a problem as females with PKU are reaching child-bearing age. Surveys have revealed that maternal phenylalanine blood concentrations greater than 1200 μmol/l are associated with fetal microcephaly, congenital heart defects and intrauterine growth retardation. It is estimated that as many as 3000 hyperphenylalaninemic females may be at risk of producing these fetal abnormalities. To examine this problem, the international maternal PKU collaborative study was developed to evaluate the efficacy of a phenylalanine-restricted diet in reducing fetal morbidity. Preliminary findings have indicated that phenylalanine restriction should begin before conception for females with PKU planning a pregnancy. Dietary control should maintain maternal blood phenylalanine levels between 120 and 360 μmol/l and should provide adequate energy, protein, vitamin and mineral intake. Pregnant hyperphenylalaninemic females who achieved metabolic control after conception or by the 10th week of pregnancy had a better offspring outcome than anticipated. The results of 402 pregnancies are reviewed.