A premature stop codon in the CYP2C19 gene may explain the unexpected sensitivity of vultures to diclofenac toxicity.

The unintended environmental exposure of vultures to diclofenac has resulted in the deaths of millions of old-world vultures on the Asian subcontinent. While toxicity has been since associated with a long half-life of elimination and zero order metabolism, the actual constraint in biotransformation is yet to be clarified. For this study we evaluated if the evident zero order metabolism could be due to defects in the CYP2C9/2C19 enzyme system.

Neonatal presentation of a patient with Liddle syndrome, South Africa.

Introduction: Liddle syndrome is an autosomal dominantly inherited disorder usually arising from single mutations of the genes that encode for the alpha, beta and gamma epithelial sodium channel (ENaC) subunits. This leads to refractory hypertension, hypokalaemia, metabolic alkalosis, hyporeninaemia and hypoaldosteronism, through over-activation of the ENaC.

Case Presentation: We describe a 5-day old neonate who presented with severe hypernatraemic dehydration requiring admission to Steve Biko Academic Hospital in South Africa in 2012.

Molecular characterization of Gyps africanus (African white-backed vulture) organic anion transporter 1 and 2 expressed in the kidney.

Gyps species have been previously shown to be highly sensitive to the toxic effects of diclofenac, when present in their food sources as drug residues following use as a veterinary medicine. Vultures exposed to diclofenac soon become depressed and die with signs of severe visceral gout and renal damage on necropsy. The molecular mechanism behind toxicity and renal excretion of uric acid is still poorly understood.

Expression and phylogeny of multidrug resistance protein 2 and 4 in African white backed vulture .

Diclofenac toxicity in old world vultures is well described in the literature by both the severity of the toxicity induced and the speed of death. While the mechanism of toxicity remains unknown at present, the necropsy signs of gout suggests primary renal involvement at the level of the uric acid excretory pathways. From information in the chicken and man, uric acid excretion is known to be a complex process that involves a combination of glomerular filtration and active tubular excretion.

Genetic diversity of HHV8 subtypes in South Africa: A5 subtype is associated with extensive disease in AIDS-KS.

Human herpes virus 8 (HHV8) is the etiological agent of all forms of Kaposi's sarcoma (KS). Six major subtypes (A-F), based on genetic variability of open reading frame (ORF)-K1, have been identified. Numerous studies point to differing tumorigenic and pathogenic properties of the HHV8 subtypes.

Kisspeptin regulation of genes involved in cell invasion and angiogenesis in first trimester human trophoblast cells.

The precise regulation of extravillous trophoblast invasion of the uterine wall is a key process in successful pregnancies. Kisspeptin (KP) has been shown to inhibit cancer cell metastasis and placental trophoblast cell migration. In this study primary cultures of first trimester human trophoblast cells have been utilized in order to study the regulation of invasion and angiogenesis-related genes by KP.

Autosomal recessive hypercholesterolaemia: discrimination of ARH protein and LDLR function in the homozygous FH phenotype.

Background: Phenocopies of homozygous familial hypercholesterolemia (hoFH) having autosomal recessive inheritance, were recently found to arise from defects in the LDL receptor (LDLR) adapter protein, called ARH, which facilitates the clearance of circulating LDL. Discrimination between the two causes of the phenotype at a clinical level may not be possible when parents display moderate hypercholesterolaemia. An effective strategy is thus required to identify the appropriate mechanism for the disorder.