P. A. Sinclair

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Hydroxysteroid sulfotransferase (SULT2A1) is a key enzyme in the testicular and hepatic metabolism of 5alpha-androstenone, which is a major component of the off-odor and off-flavor in pork known as boar taint. The goals of this study were to determine the role of testicular and hepatic SULT2A1 activity on plasma 5alpha-androstenone sulfate levels, the(More)
The hepatic metabolism of the 16-androstene steroids was investigated using isolated porcine hepatocytes. This study demonstrated that the liver is capable of producing both phase I and phase II steroid metabolites from 16-androstene steroid precursors. 16-Androstene metabolites were recovered by solid-phase extraction and identified by gas(More)
This study examined the involvement of sulphoconjugation in the biosynthesis of the 16-androstene steroids in Leydig cells of the mature boar, since the formation of steroid sulphoconjugates can reduce the levels of these steroids that accumulate in fatty tissue. Leydig cells were purified from testes of mature male pigs and incubated with pregnenolone, or(More)
Three studies examined the effects of early postnatal treatment with a GnRH agonist on plasma concentrations of testosterone, dehydroepian-drosterone sulfate, 16-androstene steroids in fat and salivary glands, androstenone in fat and plasma, and testicular development of intact male pigs. The first study involved 45 7-d-old pigs assigned to three treatment(More)
This study examined the relationship between sulfoconjugation and the degree to which 5alpha-androstenone can accumulate in fat. Analysis of the unconjugated and sulfoconjugated fractions of peripheral plasma from 25 mature Yorkshire boars and testicular vein plasma from an additional 20 mature Yorkshire boars revealed that the majority of(More)
OBJECTIVE To document the pathologic features of breast cancer in Jamaica. METHODS The pathology reports and slides of all patients diagnosed with breast cancer at the National Public Health Laboratory between January 1999 and December 2002 were reviewed. Patient age and gender side involved, number of tumours identified, tumour size, histologic type,(More)
A review of the remarkable production of steroids by the testes of the boar is presented, with the principal aims of highlighting the achievements of the Leydig cells and, at the same time, pointing to the considerable deficiencies in our understanding of its biological relevance. The onset of gonadal steroidogenesis at an early stage of sex differentiation(More)
Testicular steroid hormone concentrations in plasma of early postnatal male pigs were compared with plasma steroid hormone concentrations and androstenone concentrations in the fat of pigs at market weight. Positive correlations were found between the concentrations of fat androstenone at market weight and the concentrations of plasma androstenone (r =(More)
Unusual large dermatofibromata are reported in a 40-year-old man and a 48-year-old man, who both presented with plaques on a lower limb. The largest plaque in each case was well-defined, reddish brown, indurated and measured 50 mm x 30 mm and 70 mm x 40 mm, respectively. Several satellite lesions were present around the large plaques. Dermoscopic(More)
A review of tumours of the testis and paratesticular region diagnosed at the University Hospital of the West Indies over a 30-year period revealed 14 of the former and 22 of the latter. The testicular tumours were all malignant, with 50 per cent of them being germ-cell neoplasms. Seventeen of the 22 paratesticular tumours, (77.3%) were benign. The(More)