James A Talbot

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OBJECTIVE An immunological LH beta-subunit variant has been described, which is undetectable using monoclonal antibodies directed to the intact LH molecule alone. Subjects have been found homozygous or heterozygous for nucleotide mutations within codons 8 and 15 in the LH beta-subunit gene. The prevalence of the variant LH beta-subunit has been estimated in(More)
Allelism in the glutathione S-transferase, GSTM3 gene has been identified using PCR with specific primers to exon 6/exon 7. Sequencing showed the mutant GSTM3*B allele to have a three-base deletion in intron 6 with a frequency of 0.158. The mutation generates a recognition sequence, 5'-AAGATA-3', for the negative transcription factor YY1. GSTM3*B was(More)
OBJECTIVE To ascertain the effects on sexual function of men with epilepsy (MWE) of testosterone levels and indices of anxiety and depression. METHODS Sixty MWE taking one antiepileptic drug only (AED), with no comedication, were compared with 60 control men. Total testosterone (TT), free testosterone (FT), bioactive testosterone (BAT),(More)
OBJECTIVE Polycystic ovary syndrome is a heterogeneous disorder associated with a moderate degree of insulin resistance and a higher risk of developing NIDDM. The exact mechanism of insulin resistance is unclear. This study examines the frequency of an Xbal polymorphism of the glycogen synthetase gene (A2 allele) as a marker of insulin resistance and seeks(More)
We have measured plasma luteinizing hormone (LH), follicle-stimulating hormone (FSH), testosterone (To) by radioimmunoassay (RIA) and bioactive LH (B-LH) by in vitro bioassay at 10-min intervals over 6 h in men treated by haemodialysis for renal failure and in men after renal transplantation. Eleven normal male volunteers acted as controls. Immunoreactive(More)
Polycystic ovary syndrome (PCOS) is a common disorder characterized by chronic anovulation and infertility, hyperandrogenaemia, and frequently insulin resistance. This study investigated whether mutations in the insulin receptor gene could explain the insulin resistance in subjects with PCOS. From a total of 108 women with PCOS, a subgroup of 24 were(More)
The heterogeneity of follicle stimulating hormone (FSH) and luteinizing hormone (LH) was investigated in five women aged 29.4 +/- 3.2 years (mean +/- SD) throughout their menstrual cycles and in five post-menopausal women aged 53.8 +/- 5.6 years. Chromatofocusing (pH range 7-4) revealed menstrual cycle stage- and postmenopausal-related differences in the(More)
OBJECTIVE With isolated exceptions the only oncogene significantly associated with pituitary tumours is a constitutively active Gs protein (G alpha s). The recent cloning of the cDNA of human G alpha q has facilitated the study of this activator of the phospholipase C beta/Ca2+/ protein kinase C pathway. Since, with isolated exceptions, non-functional(More)
The extensive heterogeneity of the gonadotrophin hormones, follicle stimulating hormone (FSH) and luteinizing hormone (LH), is due primarily to the heterogeneous nature of their carbohydrate side-chains, in particular sialic acid residues. In this review, we discuss the role of carbohydrate chains in receptor binding and activation, biological activity, and(More)
We have studied bioactive and immunoreactive LH pulsatility in 11 normal men. The temporal relationship of plasma LH, testosterone, and FSH were also investigated. Blood samples were taken at 10-minute intervals for 6 h and bioactive LH levels were determined using an in vitro mouse Leydig cell bioassay. Testosterone, LH and FSH were determined by standard(More)