Publications by authors named "F I Luker"

Aim: The roles of the atrial natriuretic peptide (ANP) gene and the clearance receptor of the ANP (NPRC) gene in hypertensive groups of African ancestry are unclear. The aim of the present study was to assess the relationship between both ANP and NPRC gene polymorphisms and hypertension in Black South Africans.

Methods: 298 patients, diagnosed as having essential hypertension according to 24-hour ambulatory blood pressure (BP) measurements (mean daytime diastolic BP> 90 mm Hg) whilst off medication, and 278 normotensive control subjects of a similar African ancestry, were genotyped for polymorphic markers in intron 2 (which is in complete linkage disequilibrium with a potentially functional exon 1 variant) and exon 3 (which leads to the extension of ANP by two additional arginines) of the ANP gene.

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Aim: We evaluated whether any one variant of genes that encode for substances that could modulate renin-angiotensin-aldosterone (RAA) system activity can account for a substantial proportion of the variability of plasma RAA system profiles in black South African hypertensives (HTs).

Methods: Plasma renin activity (PRA) and aldosterone concentrations (ALD) were determined in 59 black subjects with mild-to-moderate HT off therapy on an ad libitum diet. Patients were genotyped for the angiotensin-converting enzyme (ACE) gene insertion/deletion, angiotensinogen (AGT) gene M235T, A-20C and G-6A, aldosterone synthase (CYP11B2) gene C-344T, G protein beta3-subunit (GNB3) gene C825T, G(s) protein gene C131T, atrial natriuretic peptide (ANP) gene exon 3 stop condon and intron 2, alpha-adducin gene Gly460Trp, and epithelial Na(+) channel (eNa(+) (c)) gene T594M polymorphisms.

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Body temperature and physical activity are affected by both circadian cycles and pyrogens. We injected intraperitoneally 2.5 x 10(9) cell walls of the gram-positive organism Staphylococcus aureus or sterile saline at three different times in the circadian temperature and activity rhythm of Sprague-Dawley rats.

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The insertion-deletion (ID) polymorphism of the angiotensin-converting enzyme (ACE) gene is a marker linked to differences in plasma and cardiac ACE activity as well as to an increased mortality in patients with idiopathic heart failure. We examined the possibility that ACE gene ID variants are associated with differences in left ventricular (LV) systolic performance or internal LV dimensions in a high-risk cohort of patients with idiopathic dilated cardiomyopathy (IDC). The ACE genotype was determined in 171 patients selected with IDC in New York Heart Association functional class II to III heart failure and with a LV ejection fraction of < or = 40%.

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