Influence of incubation temperature and embryonic motility on the growth of members of Caiman yacare (Daudin, 1802)

This study aimed to evaluate whether skeletal development of the Pantanal Caiman (Caiman yacare) is similarly influenced by temperature variation and controlled increases in embryo motility. All eggs were incubated at 90% humidity and 29 °C for the first 45 days. Thereafter, the incubation temperature was either maintained at 29 °C and embryos were treated with 4-aminopyridine (4-AP) on days 46, 47, 48, and 49 (Group I, 29 °C 4-AP, n = 15); maintained at 29 °C (n = 14; Group II); or at 33 °C (n = 14, Group III). Embryonic movement was measured using an Egg Buddy® digital monitor on days 30, 35, 42, 49, 56, and 60, at which point embryos were euthanized and samples were collected for analysis. No differences were observed between groups with varying incubation temperatures. In contrast, embryonic motility was greater in embryos treated with 4-AP (P < 0.001) on day 49, and this was associated with higher proportions of snout-vent and hand lengths. This study demonstrates for the first time that pharmacologically induced increases in embryo motility result in phenotypic changes to the proportion of elements during prenatal ontogeny, thereby effectively altering the adaptation of the species to specific environments.

Assessment of splanchnic perfusion with gastric tonometry in the immediate postoperative period of cardiac surgery in children

OBJECTIVE - A prospective, nonrandomized clinical study to assess splanchnic perfusion based on intramucosal pH in the postoperative period of cardiac surgery and to check the evolution of patients during hospitalization. METHODS - We studied 10 children, during the immediate postoperative period after elective cardiac surgery. Sequential intramucosal pH measurements were taken, without dobutamine (T0) and with 5mcg/kg/min (T1) and 10 (T2) mcg/kg/min. In the pediatric intensive care unit, intramucosal pH measurements were made on admission and 4, 8, 12, and 24 hours thereafter. RESULTS - The patients had an increase in intramucosal pH values with dobutamine 10mcg/kg/min [7.19+/- 0.09 (T0), 7.16+/-0.13(T1), and 7.32+/-0.16(T2)], (p=0.103). During the hospitalization period, the intramucosal pH values were the following: 7.20+/-0.13 (upon admission), 7.27+/-0.16 (after 4 hours), 7.26+/-0.07 (after 8 hours), 7.32+/-0.12 (after 12 hours), and 7.38+/-0.08 (after 24 hours), (p=0.045). No deaths occurred, and none of the patients developed multiple organ and systems dysfunction. CONCLUSION - An increase in and normalization of intramucosal pH was observed after dobutamine use. Measurement of intramucosal pH is a type of monitoring that is easy to perform and free of complications in children during the postoperative period of cardiac surgery.

NMDA receptor blockade in the periaqueductal grey prevents stress-induced analgesia in attacked mice

Microinjections of N-methyl-D-aspartate (NMDA, 0.1 and 1.0 nmol) into the periaqueductal grey (PAG) of the mouse resulted in potential antinociception. In a social conflict situation, attacked mice exhibited a marked analgesia that was prevented by prior injection of the competitive NMDA antagonist, AP-7 (2.0 nmol) or naloxone (6.0 nmol) into the PAG and also by i.p. injection of the non-competitive NMDA antagonist, MK-801 (33 nmol). These results demonstrate that NMDA receptors are involved in endogenous analgesic mechanisms activated by stress.