Female preference for male color is necessary and sufficient for assortative mating in 2 cichlid sister species

One fish, two fish, red fish, blue fish: in two cichlid fish species beauty is in the eye of the beholder. Females choose mates based on colour, blue or red, and chemical cues but only colour triggers divergent female preferences. Reliance on one prime male characteristic may have facilitated speciation in this species-pair, but in murky waters the opportunity for visual communication is dim and the fate of the two species uncertai

Administration of Steroids in Pediatric Cardiac Surgery: Impact on Clinical Outcome and Systemic Inflammatory Response

Cardiopulmonary bypass (CPB) is associated with a systemic inflammatory response. Pre-bypass steroid administration may modulate the inflammatory response, resulting in improved postoperative recovery. We performed a prospective study in the departments of cardiovascular surgery and pediatric intensive care medicine of two university hospitals that included 50 infants who underwent heart surgery. Patients received either prednisolone (30 mg/kg) added to the priming solution of the cardiopulmonary bypass circuit (steroid group) or no steroids (nonsteroid group). Clinical outcome parameters include therapy with inotropic drugs, oxygenation, blood lactate, glucose, and creatinine, and laboratory parameters of inflammation include leukocytes, C-reactive protein, and interleukin-8. Postoperative recovery (e.g., the number, dosage, and duration of inotropic drugs as well as oxygenation) was similar in patients treated with or without steroids when corrected for the type of cardiac surgery performed. After CPB, there was an inflammatory reaction, especially in patients with a long CPB time. Postoperative plasma levels of interleukin-8 were correlated with the duration of CPB time (r = 0.62, p < 0.001). Administration of steroids had no significant impact on the laboratory parameters of inflammation. Administration of prednisolone into the priming solution of the CPB circuit had no measurable influence on postoperative recovery and did not suppress the inflammatory respons

Left ventricular assist device as bridge to heart transplantation - lessons learned with the MicroMed DeBakey axial blood flow pump

Objective: The MicroMed DeBakey left ventricular assist device (LVAD) axial blood flow pump was used as bridge to heart transplantation (HTx) in patients with terminal heart failure. The aim was to evaluate this novel mechanical circulatory support system in regard to overall outcome. Methods: Prospective study in 15 HTx candidates (mean age 40±7 years) with terminal heart failure and maximal medical treatment due to ischemic cardiomyopathy (CMP, n=5), dilated CMP (n=3), restrictive CMP (n=2), unclassified CMP (n=1), metabolic CMP (n=1), valvular CMP (n=1) and congenital CMP (n=2). All patients were implanted with a MicroMed DeBakey LVAD. A rescue procedure was necessary in eight critical patients, while seven underwent elective LVAD implantation. Procedures were performed via median sternotomy, in normotherm femoro-femoral CPB (mean duration 59±1 min). Oral Marcoumar© (INR 2.0-3.0) and Aspirin© (100 mg daily) were started as soon as possible. Patients were discharged into a specialized rehabilitation clinic from which it was possible to release them home after a few weeks. Results: Successful implantation and discharge from ICU (mean stay 10±7 days) was possible in 11 patients. Seven were transplanted (mean support 50.7 days) and one is awaiting HTx (support >310 days) in the comfort of his home (NYHA I). Survival was 100% among the transplanted patients. Of the seven elective implants, five, and of the eight rescue procedures three patients underwent successful HTx. Four patients died early, while three patients died late on pump support due to intracranial hemorrhage (n=2, 73 and 76 days) and chest infection (n=1, 124 days). All survivors were discharged from hospital, with significant decrease in NYHA class (mean 3.8-2.4 (n=11)). Treadmill testing showed increased exercise tolerance, from 35 to 71 W (n=4). Plasma BNP values (mean 950-162 ng/l (n=4)) and pulmonary resistance (mean 316-194.5 dyne s/cm5 (n=3)) decreased significantly during LVAD support. Conclusions: The MicroMed DeBakey LVAD is simple to implant; outpatient treatment is safe and efficient. Patients' condition and pulmonary resistances normalize within 6 weeks, making previously considered inoperable patients amenable for HTx. HTx can be performed in low-risk situation, allowing better donor-recipient matching and improving overall outcom

Expression of adhesion molecules and cytokines after coronary artery bypass grafting during normothermic and hypothermic cardiac arrest

Objective: Cardiac surgery with cardiopulmonary bypass (CPB) results in vascular injury and tissue damage which involves leukocyte-endothelial interactions mediated by cytokines and adhesion molecules. This study was designed to demonstrate the effect of normothermic and hypothermic CPB to cytokine and soluble adhesion molecule levels in adults and to determine whether these levels correlate to the patients postoperative course. Design and patients: In 25 patients after normothermic and in 25 patients after hypothermic coronary artery bypass grafting with cardiopulmonary bypass (CPB), blood samples for cytokine and soluble adhesion molecule analysis were taken preoperatively, 24, 36, 48 h, and 6 days postoperatively. Soluble adhesion molecules (sE-selectin, sICAM-1) were measured by ELISA and cytokines (TNF-α, IL-6, IL-8) by chemilumenscent-immunoassay. Clinical data were collected prospectively. Results: Postoperatively, adhesion molecule and cytokine levels were significantly elevated after CPB. Mean plasma levels of sICAM-1 was 2.4-fold higher after 6 days. Mean plasma concentration of sE-selectin peaked after 48 h with a 2-fold increase compared to normothermic conditions. In the hypothermia group sICAM-1, sE-selectin, IL-6, and IL-8 showed significantly higher levels (P≪0.0057, P≪0.0012, P≪0.0419, P≪0.0145) after 24 h compared to the normothermia group. No clinical differences were seen. Conclusion: Adhesion molecules and cytokines are elevated after CPB. Patients after hypothermic CPB show significant higher sICAM-1, sE-selectin, IL-6, and IL-8 levels after 24 h compared to normothermic conditions. These results are mainly due to longer CPB and crossclamp times but do not alter the patient's postoperative cours

Persistent Currents in 1D Disordered Rings of Interacting Electrons

We calculate the persistent current of 1D rings of spinless fermions with short-range interactions on a lattice with up to 20 sites, and in the presence of disorder, for various band fillings. We find that {\it both} disorder and interactions always decrease the persistent current by localizing the electrons. Away from half-filling, the interaction has a much stronger influence in the presence of disorder than in the pure case.Comment: Latex file, 11 pages, 5 figures available on request, Report LPQTH-93/1

Effects of follicular phase exercise on luteinizing hormone pulse characteristics in sedentary eumenorrhoeic women

OBJECTIVE Current studies reveal little regarding the Inception of exercise-induced LH changes during physical training. This study aimed to assess the susceptibility of the hypothalamic–pituitary axis to the acute physical stress of exercise in untrained, physically inactive women. The acute effects of submaximal endurance exercise upon the pulsatile LH secretion in the follicular phase were compared with those accompanying leisurely strolling for a similar time period. SUBJECTS All subjects were eumenorrhoelc, as determined by biphasic temperature patterns, detection of the urinary LH surge, and mid-luteal serum progesterone levels. Subjects were not physically active and had little history of strenuous exercise ( V o 2 max = 38·0 ± 1·8) (mean ± SEM) ml/kg/min). DESIGN All women completed a 13·5-hour pulsatility test which included three consecutive 20-minute runs on a treadmill at 50, 60 and 70% of the subjects’maximum oxygen uptake ( n = 16). Six of these same subjects completed a separate test on another occasion in which one hour of leisurely strolling was substituted for exercise. Blood was sampled every 10 minutes via an indwelling cannula for 4·5 hours before and 8 hours after one hour of exercise and or strolling. MEASUREMENTS A pulse algorithm (Pulsar) was used to quantify LH pulse characteristics. RESULTS Exercise produced no significant effects upon LH pulse frequency or mean serum LH concentration. However, exercise of moderate intensity caused a significant increase in LH pulse amplitude ( P < 0·05). Strolling produced no significant changes in LH secretion. CONCLUSION Acute exercise of moderate intensity in the follicular phase of untrained women is an insufficient stimulus to inhibit the GnRH pulse generator in the post-exercise period, yet may produce a slight stimulatory effect on the amount of LH released per pulsePeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73507/1/j.1365-2265.1994.tb02794.x.pd