Total radical trapping antioxidant potential (TRAP) and exercise

The relationship between physical activity, physical fitness and total radical trapping antioxidant potential (TRAP) was examined in the Northern Ireland Health and Activity Survey. This was a cross-sectional population study (n = 1600) using a two-stage probability sample of the population. TRAP was calculated using the sum of the individual serum antioxidant concentrations (urate, protein thiols, ascorbate, alpha tocopherol and bilirubin) multiplied by their respective stoichiometric values. Physical fitness was determined by estimation of VO2max by extrapolation from submaximal oxygen uptake, and physical activity was recorded by computer-assisted interview. Mean serum TRAP concentrations were significantly higher in males (653 +/- 8.2 mumol/l, mean +/- SEM) compared to females (564 +/- 8.0 mumol/l) (p < 0.0001). Both male and female smokers had significantly lower TRAP values than non-smokers (males p < 0.0001, females p = 0.02). In females, there was a positive relationship of TRAP with age (p < 0.001) and body mass index (p < 0.001) but a negative relationship with physical fitness (p < 0.05). The known beneficial effects of exercise and activity do not appear to be directly mediated through increased antioxidant status.      

Neonatal jaundice: clinical and ultrasonographic findings

We reviewed the laboratory parameters, clinical information including presence or absence of stool pigmentation, and ultrasonographic findings in 67 patients with neonatal conjugated hyperbilirubinemia and liver biopsies. Hepatobiliary nuclear scintigraphy was done in 14 of the patients. Final diagnoses included extrahepatic biliary atresia, neonatal hepatitis, cystic fibrosis, metabolic liver disease, alpha 1-antitrypsin deficiency, bile duct stenosis, Alagille syndrome (arteriohepatic dysplasia), choledochal cyst, panhypopituitarism, and miscellaneous causes of intrahepatic cholestasis. A single diagnostic criterion is insufficient to distinguish the various causes of neonatal jaundice. Clinical laboratory values varied widely among patients with medical and surgical causes of jaundice. Absence of stool pigmentation was not specific for biliary atresia and was found in patients with medical causes of jaundice. Conversely, two patients with biliary atresia had pigmented stools at presentation. Ultrasonography was diagnostic only for choledochal cyst and bile duct stenosis. Nonvisualization of the gallbladder by either ultrasonography or nuclear hepatobiliary scintigraphy was nonspecific in the discrimination of medical from surgical causes of jaundice. A multidisciplinary approach to the evaluation of neonatal jaundice is necessary, since no single test or imaging modality can reliably define the cause in all cases.     

Effects of reduced uterine perfusion pressure on blood pressure and metabolic factors in pregnant rats

BACKGROUND: Elements of metabolic syndrome (eg, dyslipidemia and impaired glucose metabolism) are often present in preeclamptic pregnancies. Currently it is unclear whether these metabolic aberrations presage preeclampsia, or if these manifestations result from placental ischemia and the ensuing proinflammatory state usually present in preeclampsia. METHODS: The present study employed chronic reductions in uterine perfusion pressure (RUPP) to generate a rat model of pregnancy-induced hypertension (PIH) for the evaluation of fasting plasma concentrations of triglycerides (TGs), glucose, resistin, insulin, and glucose tolerance in late-gestation rats. RESULTS: Mean arterial pressure was increased (130 +/- 2.1 mm Hg v 100 +/- 4.3 mm Hg; all values, mean +/- SEM), and fetal weight decreased (1.93 +/- 0.08 g v 2.19 +/- 0.06 g), in RUPP dams compared with normal pregnant (NP) control dams. Maternal fasting glucose (4.2 +/- 0.3 mmol L(-1) v 3.1 +/- 0.4 mmol L(-1); P < .05) was increased in RUPP compared with NP dams. Serum TGs (2.62 +/- 0.29 mmol L(-1) v 2.45 +/- 0.51 mmol L(-1)), insulin (9.9 +/- 0.7 microU mL(-1) v 8.5 +/- 0.7 microU mL(-1)), resistin (46.25 +/- 4.19 pg mL(-1) v 49.71 +/- 4.01 pg mL(-1)), and glucose area under the curve (650 +/- 35 mmol min L(-1) v 570 +/- 34 mmol min L(-1)) were not different between the RUPP and NP dams. CONCLUSIONS: Although these findings do not rule out the hypothesis that preexisting symptoms of metabolic syndrome may contribute to the onset of preeclampsia, these data clearly show that pregnancy-induced hypertension resulting from RUPP does not elicit manifestations of metabolic syndrome in late-gestation rat dams.     

15The effect of Lower Esophageal Sphincter (LES) electrical stimulation on LES pressure

Background: Electrical stimulation (ES) of the stomach has been shown to modulate LESP. Electrical stimulation, using neural high frequency stimulation (NGES) can induce contractions of the smooth muscle of the gut. The purpose of this study was to determine if electrical stimulation of the LES can affect LESP. Methods: Four female hound dogs, weight: 20–25 kg, underwent an esophagostomy that allowed the introduction of a sleeve manometry catheter into the esophagus. They were also implanted with a pair of electrodes along the longitudinal axis of the LES. After 3 weeks of recovery, they underwent esophageal manometry recording during control and ES, performed randomly on separate days, using 4 different stimulations: 1‐Low frequency: freq: 6 cycles/min, pulse: 350 milisec, amp: 5 mAmp; 2 High‐frequency: freq: 50 Hz, pulse: 1 milisec, amp: 5 mAmp; 3‐ NGES: freq: 50 Hz, pulse:20 milisec, amp:10 volts; 4‐ High‐frequency, circular: freq: 20 Hz, pulse:1 milisec, amp:5 mAmp. All recordings were performed 1 hour after consumption of 3 ounces of canned dog food, to prevent fluctuations in LESP and under mild sedation (acepromazine 0.5 mg kg^­1). Tests consisted, during ES days, of 3 periods of 20 minutes each: control , stimulation and post stimulation. The effect of NGES was also tested under anesthesia and following administration of L‐NAME 50 mg kg^­1 IV. and also atropine 0.05 mg kg^­1 IV. Analysis: area under the curve (AUC) and pressure were compared among the 3 periods. Data shown as mean ± SD, ANOVA and t‐test, p < 0.05. Results: Sustained increase in LESP was observed during low frequency stimulation, 32.1 ± 12.8 vs. 42.4 ± 18.0 vs. 50.1 ± 23.6, control vs. stimulation vs. post stimulation respectively, p = 0.013. AUC also significantly increased during and after stimulation, 39,320.3 ± 15,722 vs. 51,294 ± 21,826 vs. 59,823.6 ± 28,198.4 mmHgxsec, control vs. stimulation vs. post stimulation respectively, p = 0.01. There was no significant change with other types of ES. NGES induced an initial rise in LESP followed within few seconds by relaxation with slow resumption of pressure over a 1 minute period. L‐NAME increased LESP and augmented the initial rise in LESP following NGES but markedly diminished or abolished the relaxation phase. Atropine lowered LESP and abolished the initial rise in LESP induced by NGES. Conclusions: Low frequency ES of the LES increases LESP in conscious dogs. NGES has dual effect on LESP: an initial stimulation, cholinergically mediated, followed by relaxation mediated by nitric oxide.     

Multinuclear NMR investigations of probe construction materials at 4.7 T

Since background signal from NMR probes can overwhelm the signal from a sample, the NMR analysis of plastics or machinable ceramics is a prerequisite to their use in probe implementations. The contributions from a variety of materials to proton, fluorine, and carbon NMR spectra are presented.