On-demand IC351 (Cialis) enhances erectile function in patients with erectile dysfunction

IC351 (Cialis) is a selective inhibitor of PDE5. The efficacy and safety of on-demand dosing of IC351 in men with erectile dysfunction was assessed in a multicenter, double-blind, placebo-controlled study. One hundred seventy-nine men (mean age: 56 y) were randomized to receive placebo or IC351 at doses of 2, 5, 10 or 25 mg, taken on demand over a 3-week period. The primary endpoints were change from baseline in responses to Questions 3 (Q3) and 4 (Q4) of the International Index of Erectile Function (IIEF). IC351 significantly improved IIEF Q3 scores at all doses vs placebo (P < or =0.003). IC351 also significantly improved IIEF Q4 scores in all but the 2 mg group (P < or =0.0003). No significant changes in laboratory values, ECGs, or blood pressure were observed. The most common adverse events were headache and dyspepsia. The conclusion of this study was that on-demand IC351 at doses up to 25 mg was well tolerated and significantly improved erectile function.     

Alpha 4 beta 1 and alpha 5 beta 1 are differentially expressed during myelopoiesis and mediate the adherence of human CD34+ cells to fibronectin in an activation-dependent way

To study the receptors involved in the interaction between extracellular matrix proteins and hematopoietic progenitor cells, we analyzed the expression of beta 1 integrins on CD34+ bone marrow cells by means of immunoflowcytometry. Alpha 4 beta 1 and alpha 5 beta 1 were expressed, whereas alpha 1 beta 1, alpha 2 beta 1, alpha 3 beta 1, alpha 6 beta 1, and alpha v beta 1 were virtually absent. Furthermore, we assessed the alpha 4 and alpha 5 expression on committed myeloid progenitor cells. These colony-forming cells were detected in the alpha 4 dull fraction and the alpha 5 dull fraction. During myeloid differentiation, both in vivo and in vitro, a differential expression of alpha 4 beta 1 and alpha 5 beta 1 was observed. alpha 5 beta 1 was found to be lost at the myelocytic-metamyelocytic stage, before the loss of alpha 4 beta 1, at the band stage. Functional studies showed no binding of erythroid progenitor-depleted, CD34+ bone marrow cells to fibronectin. However, protein kinase C activation strongly induced fibronectin binding (68% of the cells). Inhibition experiments with specific antibodies and peptides showed the binding to be mediated by both alpha 4 beta 1 and alpha 5 beta 1. Also, colony-forming cells of granulocytes and macrophages were demonstrated to adhere to fibronectin in an activation-dependent way. During granulocyte colony-stimulating factor-induced in vitro maturation, the activation-dependent fibronectin binding capacity is gradually lost. We conclude that: (1) CD34+ bone marrow cells express alpha 4 beta 1 and alpha 5 beta 1; (2) the expression of alpha 4 beta 1 and alpha 5 beta 1 is differentially expressed during myeloid differentiation; and (3) binding of CD34+ bone marrow cells to fibronectin is activation dependent.     

Vagal hyperactivity in stress induced gastric ulceration in rats

Indirect evidence suggests that stress ulceration is provoked by vagal hyperactivity. However, direct evidence of hypervagal activity during stress conditions is lacking. Experiments were designed to directly measure vagal activity under different stress conditions in rats. Starvation stress for 48 h did not change the mean amplitude of action potentials, but their frequency was significantly decreased. Restraint stress at 22°C increased vagal activity, both amplitude and frequency, in the first 60 min; these responses were markedly enhanced by cold (4°C) and persisted for at least 2 h. Starvation for 48 h did not induce any gastric mucosal lesions. Restraint alone produced petechiae in the gastric mucosa, but cold restraint induced severe haemorrhagic ulcers. It is concluded that cold restraint stress provokes a prolonged vagal hyperactivity, which is one of the causative factors for gastric ulceration.