Management of major colonic haemorrhage

Major colonic haemorrhage remains a difficult diagnostic and therapeutic problem. We propose that those patients who continue to bleed after resuscitation are best served by immediate laparotomy. High flow antegrade irrigation and intra-operative colonoscopy can then be used to localize the site of bleeding and allow appropriate excisional surgery rather than blind colonic resection.     

Regular ingestion of tea does not inhibit in vivo lipid peroxidation in humans.

Prospective studies suggest that tea may protect against cardiovascular disease. A potential mechanism for such an effect involves inhibition of lipid peroxidation by polyphenolic antioxidants derived from tea. Our objective was to determine whether regular ingestion of tea could inhibit in vivo lipid peroxidation. Two controlled intervention studies assessed the effects of regular ingestion of tea on lipid peroxidation determined by measurement of urinary F(2)-isoprostane excretion. Study 1: The effects of 1000 mL/d of green tea and black tea were compared with hot water containing caffeine in 13 subjects with elevated blood pressure using a randomized 3-period (7 d each) crossover design. Study 2: The effects of 1250 mL/d of black tea were compared with hot water in 22 subjects with mildly raised serum total cholesterol concentrations using a randomized 2-period (4 wk each) crossover design. F(2)-isoprostane excretion was not altered after regular ingestion of green tea (273 +/- 48 pmol/mmol creatinine) or black tea (274 +/- 39 pmol/mmol creatinine) in comparison with hot water (263 +/- 47 pmol/mmol creatinine; Study 1), or by regular ingestion of black tea (334 +/- 71 pmol/mmol creatinine) in comparison with hot water (355 +/- 75 pmol/mmol creatinine; Study 2). These results do not support the suggestion that polyphenolic antioxidants derived from tea inhibit in vivo lipid peroxidation.     

Surveillance around hazardous waste sites: geographic information systems and reproductive outcomes.

The purpose of this paper is to discuss the potential for integrating surveillance techniques in reproductive epidemiology with geographic information system technology in order to identify populations at risk around hazardous waste sites. Environmental epidemiologic studies have had problems with estimating or measuring exposures to individuals, and of detecting effects when the exposure is low, but continuous. In addition, exposures around hazardous waste sites are complex and frequently involve chemical mixtures. The birth weight of human babies has been reported to be sensitive to many environmental influences. Birth weight can be analyzed as a continuous variable or as a dichotomous one using the standard cutpoint of 2500 g or less to indicate low birth weight. It has the potential to be a powerful surveillance tool since exposures to the fetus reflect maternal and paternal exposures. The advent of recent environmental regulations pertaining to hazardous waste sites has greatly increased the availability of environmental data for many sites. The major problem with incorporating these data into epidemiologic studies has been with the logistics of data management and analysis. Computer-assisted geographic information systems hold promise in providing capabilities needed to address the data management and analysis requirements for effective epidemiologic studies around to hazardous waste sites.     

Postnatal white matter necrosis in preterm infants.

One hundred twenty-seven infants less than 36 weeks of gestation (mean +/- SE = 31 +/- 3.2 weeks) were studied with echoencephalography to determine the incidence and complications associated with white matter necrosis. Ten infants (8%) developed cysts ten or more days after birth, indicating postnatal onset of white matter necrosis. Univariate analysis showed that postnatal white matter necrosis was significantly associated with maternal infection (other than urinary infection), respiratory distress syndrome, and longer requirement of an oxygen concentration greater than 40%. Forward logistic regression analysis showed postnatal white matter necrosis to be associated with maternal infection, chronic placental infarction, congenital pneumonia, and longer requirement of an oxygen concentration greater than 40%. Neurodevelopmental outcome was abnormal during infancy in 4 of the 6 survivors with postnatal white matter necrosis. Severe respiratory disease and maternal and/or fetal infection appear to increase the risk of the immature brain to white matter necrosis, predisposing the infants to subsequent neurodevelopmental delay.     

High energy phosphate metabolism in experimental permanent focal cerebral ischemia: an in vivo 31P magnetic resonance spectroscopy study

Relative levels of phosphate metabolites in the brain were examined in vivo by 31P magnetic resonance spectroscopy (MRS) in 50 Sprague-Dawley rats before, during, and after induction of focal permanent cerebral ischemia. After acquisition of baseline spectra, rats were subjected to injury within the core of the MR spectrometer, and 31P spectra were collected for 60 min after injury: in 7 rats, permanent, acute focal cerebral ischemia was induced (ischemia group); in 6 rats, mild hypoxia (FiO2 14%) was induced at the time of the ischemic insult and was maintained for 20 min (ischemia-hypoxia group); in 6 rats, mild hypoxia (FiO2 14%) only was induced for 20 min (hypoxia group). Control studies were performed in 25 rats. Cerebral intracellular pH, calculated from the chemical shift of inorganic phosphate (Pi), decreased immediately after injury in the ischemia and ischemia-hypoxia groups. The first 31P spectrum obtained after injury was characterized by an increase in Pi and a decrease in phosphocreatine (PCr) in the ischemia and ischemia-hypoxia groups; these changes in spectra were significantly greater in the ischemia-hypoxia group. No significant changes in adenosine triphosphate (ATP) were found in either group. Within 60 min of occlusion, 31P spectra returned toward baseline spectra in both ischemia-hypoxia and ischemia groups. No significant changes were seen in spectra of rats subjected to hypoxia alone. These results confirm that 31P MRS is a sensitive measure of early changes of high energy metabolites in focal cerebral ischemia.(ABSTRACT TRUNCATED AT 250 WORDS)     

Bereavement and remarriage for older adults

The purpose of this study was to assess differences in bereavement outcomes between surviving spouses aged 50 and over who remarried within 4-5 years and those who did not. Fifteen bereaved respondents out of 192 in a longitudinal prospective study who later remarried were compared with 15 other matched nonremarried respondents. Analyses of sociodemographic data, standardized measures of depression, life-satisfaction, resolution of grief, and self-perceived ratings of coping, stress, self-esteem, health and social support were performed with correlated t-tests. Statistically significant differences indicated that over time, the remarried subjects displayed more positive outcomes.     

Cardiovascular responses of pregnant women during aerobic exercise in water: a longitudinal study

To determine the effects of pregnancy on the cardiovascular responses to immersion and exercise in water, 12 women completed 20 min of immersion and 20 min of bicycle ergometry at 60% predicted VO2max in 30 degrees C water during their 15th, 25th, and 35th week of pregnancy as well as 8-10 weeks post partum. Immersion lowered the resting heart rate approximately 8 bts/min (P less than 0.05). Exercise in water also resulted in a lower heart rate as compared with the same level of exercise on land (132 +/- 4 vs 149 +/- 6 bts/min; P less than 0.05). Both the rest and exercise heart rate responses were independent of duration of pregnancy or pregnancy status. Post partum exercise cardiac output averaged 9.9 +/- 0.4 l/min, significantly lower (P less than 0.05) than the 15th (12.7 +/- 0.5), 25th (14.7 +/- 0.5), or 35th week (15.1 +/- 0.7 l/min). Total peripheral resistance was greatest (P less than 0.05) post partum (657 +/- 29 dyn.s/cm5) compared with either the 15th (515 +/- 27), 25th (407 +/- 18), or 35th week (450 +/- 23). The results indicate that exercise in water lowers the heart rate compared with land exercise at the same metabolic rate. The combined effect of exercise, water, and pregnancy may elevate the cardiac output more than expected on land, but the same general pattern of exercise response will be evident throughout the duration of pregnancy. The results further suggest that water alters the heart rate and blood pressure responses such that land-derived exercise target heart rates should not be used to prescribe exercise intensity in water.