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Cyclic tetrapeptides containing trifluoromethyl and pentafluoroethyl ketone as zinc binding functional group were synthesized as potent HDAC inhibitors. Evaluation by human HDAC inhibition assay and p21 promoter assay showed that these inhibitors are promising anticancer agents.

Background: The effect of University of Wisconsin (UW) solution perfusion for extremity preservation is still unknown although it is widely used. The purpose of this study is to examine the effect of UW solution perfusion on skeletal muscle preservation in a rat model., Materials and Methods: Rat hindlimbs were amputated and either preserved with UW solution perfusion (UW perfusion group) or given no perfusion (no-perfusion group) for 5 h at 25 degrees C. They were then transplanted to other isogeneic rats. ATP in the muscle and serum creatine phosphokinase were measured after 24 h of reperfusion. The vascular endothelial function of the femoral artery rings was measured before and after 24 h of reperfusion in the presence or absence of indomethacin (cyclooxygenase inhibitor) and L-NMMA (nitric oxide synthase inhibitor). TEA (calcium-activated potassium channel inhibitor) was also used to verify the vasodilator function. Reperfusion blood flow was monitored during the first 2 h of reperfusion., Results: ATP in the UW perfusion group was significantly decreased after 24 h of reperfusion, while that in the no-perfusion group recovered. Reperfusion blood flow in the UW solution perfusion group was significantly lower than that in the no-perfusion group. Acetylcholine-induced relaxation in the UW perfusion group was significantly reduced before and after 24 h of reperfusion compared to that in the no-perfusion group and was mostly diminished by indomethacin and L-NMMA administration., Conclusions: Skeletal muscle injury is augmented by UW solution perfusion, probably due to deterioration of the vascular endothelial function resulting in blood supply diminution.

Background: The involvement of nitric oxide (NO) in ischemia-reperfusion injury remains controversial and has been reported to be both beneficial and deleterious. The purpose of this study was to examine the contribution of NO and superoxide to skeletal muscle function using an ischemic revascularized hind limb model in rats., Patients and Materials: Warm ischemia produced by vascular pedicle clamping was sustained for 3 h. The animals were divided into four groups according to the solution administrated: (1) saline, (2) N-methyl-L-arginine acetate (L-NMMA), (3) L-NMMA + N-(N-L-g-glutamyl-S-nitroso-l-cysteinyl)glycine (S-nitrosoglutathione), or (4) superoxide dismutase (SOD). Saline, L-NMMA, or L-NMMA + S-nitrosoglutathione was infused for the first 2 h of reperfusion. The SOD was administered as an intravenous bolus 5 min before the onset of reperfusion. Postischemic blood flow was measured by a Doppler flow meter. Muscle contractile function was determined after 24 h of reperfusion., Results: Postischemic blood flow was significantly decreased by the L-NMMA infusion compared with that in the saline-treated group. No significant difference in postischemic blood flow was noted in the saline-, L-NMMA + S-nitrosoglutathione-, and SOD-treated groups. Contractile function of the gastrocnemius muscle in the L-NMMA-and SOD-treated groups, but not in the L-NMMA + S-nitrosoglutathione group, was significantly better than that in the saline-treated group., Conclusion: Limiting postischemic blood flow and SOD infusion are both beneficial in decreasing the ischemia-reperfusion injury of skeletal muscle. S-Nitrosoglutathione infusion following suppression of endogenous NO production does not reduce ischemia-reperfusion injury.

Background: Despite the established preservation method for major organs of perfusion followed by immersion at hypothermia, a standard preservation technique for skeletal muscle is still a matter of controversy. The purpose of this study is to examine the effect of perfusion on the preservation of skeletal muscle in amputated limbs., Materials and Method: The rat hindlimb was amputated for perfusion with Euro-Collins (EC) or University of Wisconsin (UW) solution at different perfusion pressures (40 or 100 cm-gravity). After certain ischemic periods (4 or 5 h), the skeletal muscle viability was determined by measuring the tissue content of adenosine triphosphate (ATP)., Result: The UW solution perfusion group maintained better ATP levels than the EC solution group when the ischemic period was extended to 5 h. The perfusion pressure of 100 cm-gravity was more effective for preserving muscle viability than 40 cm-gravity with both EC and UW solutions., Conclusion: UW solution might be adequate to preserve muscle viability and perfusion pressure is recommended at 100 cm-gravity rather than at minimal pressure (40 cm-gravity), which washes out stagnant blood.

The Picazuro Pigeon nests in all months of the year in southeastern Brazil. Nest material is plucked from trees or ground and carried to build a frail and transparent nest of sticks where one egg is laid. Female and male alternate in incubation and brooding and do not soil the nest with feces.

An August or winter nestling of Eupetomena macroura was fed only every 40-50 min for at least 24 days in the nest, with fewer feedings at midday. As in other hummingbirds, it was brooded only the first week or two, and left alone even on cool nights after 12 days, probably due to the small nest size. The female attacked birds of many non-nectarivore species near the nest, in part probably to avoid predation. Botfly parasitism was extremely high, as in some other forest-edge birds.

The effect of water and saliva contamination on the bond strength of metal orthodontic brackets cemented to etched (10% polyacrylic acid) and unetched human premolar enamel was investigated. Two bonding agents were used: one commercially available product (LC) and one experimental (EX) light-cured glass ionomer. Shear bond strength was measured after aging for 5 minutes, 15 minutes, and 24 hours. The results were compared by ANOVA and Scheffe's tests at p = 0.05. For LC, the bond strength of brackets bonded to etched enamel, with and without contamination, was statistically higher than that of brackets bonded to unetched enamel for all aging times. An exception was the bond strength to unetched enamel with saliva contamination after 24 hours; for EX, this value was statistically higher than that measured on unetched enamel with water contamination. Contamination by saliva did not reduce bond strength to unetched enamel. For both etched and unetched enamel, there was no significant difference between LC and EX after 24 hours for all contamination conditions.