Ovarian hormones can organize the rat corpus callosum in adulthood

The rat corpus callosum (CC) is larger in males than females, and is responsive to hormone manipulations during development. Previous data suggest that CC sensitivity to testosterone ends by postnatal day 8 (P8). In contrast, responsivity to ovarian hormones extends as late as P25. The current series of experiments investigates whether ovarian hormone effects on the callosum are permanent and whether CC sensitivity to ovarian hormones extends beyond P25. We found that P70 ovariectomy (Ovx) did not affect callosal size, suggesting that ovarian hormone exposure sometime prior to P70 is sufficient to feminize the CC, and that once the callosum is feminized, the effects can not be reversed. We also found that P25 ovariectomy enlarged, or defeminized, adult female CC, whereas ovary transfer starting on P55 or P70 counteracted this enlarging effect, resulting in feminized adult CC. Thus, although a previously feminized callosum is not affected by P70 ovarian hormone removal, a not-yet feminized callosum can still be feminized after P70. These findings indicate that there is flexibility in the developmental window within which the female brain is responsive to the active feminization process initiated by ovarian hormones.     

Sensory stimulation increases cortical expression of the fragile X mental retardation protein in vivo

Fragile X syndrome is a common cause of mental retardation that results from the absence of the fragile X mental retardation protein (FMRP), an RNA binding protein whose function remains unclear. Recent in vitro work has demonstrated that the protein is translated near the synapse in an activity dependent manner [33]. We therefore asked whether expression of FMRP might be altered by neuronal activity in vivo. Using immunoblots of different sub-cellular fractions of the rat somatosensory cortex, we show that the levels of FMRP increase significantly following unilateral whisker stimulation, a model of experience dependent plasticity. This increase is greatest between 2 and 8 h after the stimulus and is seen in both a synaptosomal fraction as well as a sub-cellular fraction enriched for polyribosomal complexes. In contrast, detectable levels of FMRP within the somatosensory cortex show either a decrease or no change after a kainic acid induced seizure compared to water treated controls. Our findings demonstrate that FMRP expression levels are modulated in vivo in response to neuronal activity and suggest a role for FMRP in activity dependent plasticity.     

Right heart circulatory support facilities coronary artery bypass without cardiopulmonary bypass

BACKGROUND: Revascularization of the posterior wall often causes hemodynamic instability in beating heart coronary artery bypass (CAB). Our previous clinical studies have shown that tilting the heart primarily alters right-heart hemodynamics. The purpose of this study was to evaluate right-heart support in clinical cases. METHODS: Seventeen patients underwent beating heart CAB with right-heart support. The right-heart support system (A-Med Systems, West Sacramento, CA) consisted of a coaxial cannula placed through the right atrium and the tip of the cannula positioned in main pulmonary artery. Blood was removed from the right atrium and returned to the main pulmonary artery. RESULTS: Elective beating heart CAB was accomplished successfully in 17 patients with right-heart support. Anastomoses performed were left anterior descending coronary artery (11), diagonal (3), circumflex (5), obtuse marginal artery (11), and right coronary artery (10). Right-heart support between 1 and 3 L/min improved hemodynamics especially in the circumflex position. No device-related patient incidents occurred, nor were there incidents of infection or air embolism. All 17 patients were discharged to their homes. CONCLUSIONS: The right-heart support system was safe without complications. Exposure of the posterior wall was possible in all cases without hemodynamic compromise.     

Clinical Outcomes and Resource Use for Infants With Hypoplastic Left Heart Syndrome During Bidirectional Glenn: Summary From the Joint Council for Congenital Heart Disease National Pediatric Cardiology Quality Improvement Collaborative Registry

The National Pediatric Cardiology Quality Improvement Collaborative (NPC-QIC) registry captures information on interstage management of infants with hypoplastic left heart syndrome (HLHS). The purpose of this study was to identify interstage risk factors for increased resource use and adverse outcomes during bidirectional Glenn (BDG) hospitalization. All infants in the NPC-QIC registry (31 United States hospitals) undergoing BDG surgery were included (December 2009 to August 2010). Patient demographics, interstage variables, operative procedures, and complications were recorded. Days of hospitalization, ventilation, inotrope use, and complications were surrogates of resource use. Logistic regression analysis determined the associations between predictor variables and resource use. Of 162 infants, 105 (65 %) were males. At BDG, the median age was 155 days (range 78–128), mean weight-for-age z-score was ?1.6 ± 1.1, mean length-for-age z-score was ?1.5 ± 1.7, and mean preoperative oxygen saturation was 78 % ± 7 %. Caloric recommendations were met in 60 % of patients, and 85 % of patients participated in a home-surveillance program. Median days of intubation, inotrope use, and hospitalization were 1, 2, and 7, respectively. There were 4 post-BDG deaths and 55 complications. In multivariate analysis, lower weight-for-age z-score, female sex, and aortic atresia with mitral stenosis were associated with a higher risk of BDG complications. Meeting caloric recommendations before BDG was associated with fewer hospitalization days. Lower weight-for-age z-score was an independent and potentially modifiable risk factor for BDG complications. HLHS infants who met caloric recommendations before BDG had a lower duration of hospitalization at BDG. These data justify targeting nutrition in interstage strategies to improve outcomes and decrease costs for patients with HLHS.     

Effect of antipyrine on prostaglandin levels and uterine and umbilical blood flow

Antipyrine and 4-aminoantipyrine have been used for approximately 20 years to measure uterine and umbilical blood flow. Fetal infusion of 4-aminoantipyrine has been shown to decrease myometrial activity and to significantly lower prostaglandin F2 alpha metabolite levels. Since prostaglandins are thought to be important in regulating uterine and umbilical blood flow, their decrease could cause significant changes in blood flow. The purpose of the present study was to evaluate the effects of antipyrine on uterine and umbilical blood flow as measured with electromagnetic flow probes and to determine whether antipyrine causes significant changes in levels of prostaglandin E2, prostaglandin F2 alpha metabolite, and prostaglandin I2 measured as 6-keto-prostaglandin F1 alpha. Antipyrine infusion produced significant reductions in the uterine venous levels of prostaglandin E2 and prostaglandin F2 alpha metabolite (p less than 0.05). These reductions in prostaglandin levels were not associated with any significant changes in maternal blood pressure, heart rate, uterine blood flow, or oxygen content. Although fetal prostaglandin levels tended to decrease during the antipyrine infusion, these changes were not significant. Fetal blood pressure, heart rate, umbilical blood flow, PaO2, and oxygen content were not significantly altered. These data suggest that the antipyrine method does not affect basal blood flow in the uterine or umbilical circulation even though uterine prostaglandin levels are significantly decreased.     

New guidelines for maternal and neonatal resuscitation

New evidence has prompted changes in our national cardiopulmonary resuscitation guidelines for both neonates and adult patients. The purpose of this article is to provide an overview of the changes recommended by the American Heart Association, Academy of American Pediatrics, and the American College of Obstetrics and Gynecology. In addition, a strategy for implementing these guidelines into practice is suggested.     

Health-enhancing physical activity,psychological needs satisfaction,and well-being: Is it how often,how long,or how much effort that matters?

The objective of this study was to examine the role of basic psychological need satisfaction as a potential mediator of the relationship between health-enhancing physical activity (HEPA) and well-being. Participants (N = 201) were young adults who recalled their HEPA behavior, experiences of psychological need satisfaction, and levels of well-being across multiple indicators using a cross-sectional design targeting the previous day. Results from path analysis demonstrated that effort put forth in HEPA activities, as opposed to frequency or duration of HEPA, predicted well-being. Further, psychological needs satisfaction mediated between 10% and 44% of the HEPA-Effort – well-being relationship. Overall, these findings lend credence to the notion that effortful investment is associated with well-being when engaged in HEPA, and that the satisfaction of basic psychological needs may act as a salient explanatory mechanism partially accounting for that relationship.