Elevated Lactate Secondary to Gastrointestinal Beriberi.

Thiamine deficiency usually occurs with prolonged nutritional deficiency and is almost universally identified with Wernicke's encephalopathy or beriberi. It is also, however, a rare cause of elevated lactate and gastroenterological symptoms. This case report describes a 30-year-old man with 2 weeks of gastroenterological symptoms and intermittent oral intake, who was found to have an elevated lactate level.

p21WAF1/CIP1 is a common transcriptional target of retinoid receptors: pleiotropic regulatory mechanism through retinoic acid receptor (RAR)/retinoid X receptor (RXR) heterodimer and RXR/RXR homodimer.

The divergent response and the molecular mechanisms underlying the anti-cancer effects of retinoid X receptor (RXR) ligand (rexinoid) therapy are poorly understood. This study demonstrates that ligand-activated RXR homodimer facilitated G(1) arrest by up-regulation of p21 in vitro and in vivo but failed to induce G(1) arrest when p21 expression was blocked by p21 small interfering RNA. RXR ligand-dependent p21 up-regulation was transcriptionally controlled through the direct binding of RXR homodimers to two consecutive retinoid X response elements in the p21 promoter.