Does dopamine block the spawning of the acroporid coral Acropora tenuis?

Most corals undergo spawning after a particular moon phase, but how moon-related spawning is endogenously regulated in corals remains unknown. The objective of the present study was to evaluate whether dopamine (DA) affects spawning in Acropora tenuis. When pieces of four A. tenuis colonies were reared under a natural photoperiod and water temperature, spawning was observed after the predicted moon phase. After exposure to water containing DA at 0.1 µM, pieces of the same colonies only released 5 to 10 bundles. Co-treatment with DA and pimozide (D1 and D2 receptors antagonist), but not domperidone (D2 receptor antagonist), induced mass release of bundles from the colonies. A cross-experiment revealed high fertilization rates between the control colonies (95%) and between the control and DA-treated colonies (90%), suggesting that gametes developed normally in coral tissue. Therefore, DA appears to have an inhibitory effect on the spawning of A. tenuis.

Low-dose MTX for the treatment of acute and chronic graft-versus-host disease in children.

We report the results of a retrospective analysis in 27 pediatric patients who received low-dose MTX as the second-line treatment for steroid-refractory or -dependent acute and chronic GVHD. Between July 2000 and May 2006, 10 patients with aGVHD and 17 with cGVHD were treated with MTX at a dose of 3-10 mg/m(2) weekly. Seven of ten patients (70%) with aGVHD responded well to MTX, thus resulting in the achievement of either a complete response (CR) or a partial response (PR). The dose of prednisone could be reduced to equal to or lower than 1 mg/kg in the responding patients at the end of MTX therapy. The median number of MTX administrations was five (range, 1-7). Ten (58.8%) of seventeen patients with cGVHD achieved CR or PR. The dose of prednisone could be reduced to lower than 0.4 mg/kg in 16 of 17 patients and seven patients could discontinue prednisone. The median duration of MTX administration was 18 months (range, 1-68). The toxicities of grade III to IV occurred in only six patients presenting cytopenias or elevated levels of serum transaminases. Low-dose MTX was tolerable and effective for the steroid-refractory or -dependent GVHD in reducing the dose of steroid without increasing the risk of opportunistic infection.