Differences among heat-treated, raw, and commercial peanut extracts by skin testing and immunoblotting.

BACKGROUND: Peanut allergenicity has been reported to be influenced by heat treatment, yet the commonly available extracts for skin prick testing (SPT) are derived from raw extracts. OBJECTIVE: To assess the effect of heat treatment on the SPT reactivity and specific IgE binding to peanut. METHODS: Three commercial extracts and 3 laboratory-prepared extracts, including raw, roasted, and boiled, were used for SPT in 19 patients with suspected peanut allergy and in 4 individuals who eat peanut without any symptoms. Serum samples were obtained to measure total IgE in addition to specific IgE binding to the study extracts by immunoblotting. Peanut allergy was confirmed with challenge test unless the individual had a convincing history of a severe reaction. RESULTS: Eleven study participants were considered peanut allergic based on a strong history or positive challenge test result. SPT with the prepared and commercial reagents showed that the boiled extract had the highest specificity (67% vs 42%-63% for the other extracts). The prepared extracts showed similar SPT sensitivity (81%). Three patients with a history of severe reaction and elevated specific IgE levels to peanut to the 3 study extracts had variable SPT reactivity to 1 or more of the commercial extracts. IgE binding to Ara h 2 was found in nearly all patients, regardless of their clinical reactivity. CONCLUSIONS: None of the extracts tested showed optimal diagnostic reliability regarding both sensitivity and specificity. Perhaps testing should be performed with multiple individual extracts prepared by different methods.

Postoperative effects of anesthesia and surgery on resting energy expenditure in horses as measured by indirect calorimetry.

In this study, we aimed to define the effects of anesthesia and surgery on the resting energy expenditure of horses in experimental conditions. Six horses were used in a longitudinal study with 2 study periods: before and after anesthesia and surgery. Every horse underwent a standard 90-min ventral midline exploratory laparotomy. Oxygen uptake (VO2) and carbon dioxide output (VCO2) were measured, with the use of a closed-circuit spirometry system, on 5 consecutive days immediately before and after the surgery. In 3 consecutive 5-min periods each day, the expired air was collected in a Collins spirometer. Samples of the expired gas were drawn from the spirometer through a drying column into O2 and CO2 analyzers. Resting energy expenditure was calculated as [(VO2 STPD*3.94) + (VCO2 STPD*1.11)]*1.44. This study showed that anesthesia and ventral midline exploratory laparotomy in experimental conditions increase the postoperative caloric demand in horses by an average of 1.0 Mcal/d, which represents approximately a 10% increase (P = 0.03). Additional studies in critically ill horses after surgery are needed to determine their caloric needs and to optimize their nutritional management.

Effects of hyperoxic training on performance and cardiorespiratory response to exercise.

PURPOSE: To determine whether training in a hyperoxic environment would result in greater increases in VO2max and performance at 90% VO2max as compared with training in normoxia. METHODS: In a single blind design nine athletes trained for 6 wk on a cycle ergometer 3 d.wk(-1), 1 h.d(-1) (10 x 4-min intervals, with 2 min of rest between intervals) at 90% HR(max). Training HR range was maintained by adjusting the power output. Subjects were randomly assigned to H (60% O2) or N (21% O2) breathing conditions for training. After 12 wk of detraining, a second 6-wk training protocol was completed with the breathing conditions reversed. VO2max, performance time at 90% VO2max and cardiorespiratory response to a steady-state exercise at 80% VO2max were measured pre- and posttraining. All pre- and posttraining tests were conducted under normoxic conditions. RESULTS: There were no significant differences between pretraining results for any of the parameters. Power output was 8.1% higher while training in H compared with N, to maintain training HR. Both H and N training resulted in increased performance time, with H being greater than N. Although there was a trend for a greater increase in VO2max after H versus N training, this difference was not significant. HR(max) did not change for H or N. HR VE at 80% VO2max decreased posttraining with no differences between H and N. CONCLUSION: The data showed that a higher power output was required to maintain HR during H training. This increased training intensity during H resulted in improved exercise performance whereas cycling at 90% VO2max in room air and may be due to peripheral factors because cardiorespiratory responses were similar.

Comparison of the standard predictive equation for calculation of resting energy expenditure with indirect calorimetry in hospitalized and healthy dogs.

OBJECTIVE: To determine the level of clinical agreement between 2 methods for the measurement of resting energy expenditure (REE). DESIGN: Prospective case series. ANIMALS: 77 dogs. PROCEDURE: Oxygen consumption (Vo2) and CO2 production (Vco2) were measured with an open-flow indirect calorimeter in healthy (n = 10) and ill (67) dogs. Measurements were collected at 3 time periods on 2 days. The Vo2 and the Vco2 measurements were then used to calculate the REE values. RESULTS: Mean values of measured (MREE) and predicted (PREE) REEs in healthy dogs and a dog with medical illnesses or trauma were not significantly different. There was a significant difference on day 2 between the MREE and PREE in the group of dogs recovering from major surgery. More importantly, there was significant variation between the PREE and MREE on an individual-dog basis. The PREE only agreed to within +/- 20% of the MREE in 51% to 57% of the dogs. CONCLUSIONS AND CLINICAL RELEVANCE: The level of agreement between these two methods for determining the 24-hour REE was poor in individual dogs. The level of disagreement between the 2 methods indicates that these methods may not be used interchangeably in a clinical setting. Measurement of REE by use of indirect calorimetry may be the only reliable method of determining REE in an individual ill or healthy dog.

Facial cooling enhances exercise-induced bronchoconstriction in asthmatic children.

PURPOSE: Exercising in cold air enhances bronchial responsiveness (BR) as compared with exercising in warm air. This may be due to intrathoracic cooling or to increased vagal activity caused by facial cooling. The purpose of this study was to compare the effects on BR of cold air inhalation and of facial exposure to cold air, as well as the combined effect of both. METHODS: Fourteen children with asthma (eight girls) performed four exercise challenge tests in a climatic chamber, under one of the following conditions: 1) inhaling warm air while the face was exposed to warm air (WW, 21 degrees C, 25% relative humidity (RH)); 2) inhaling warm air while the face was exposed to cold air (WC, 0 degrees C, 80% RH); 3) inhaling cold air while the face was exposed to cold air (CC); and 4) inhaling cold air while the face was exposed to warm air (CW). The study was analyzed, using a one- and two-way ANOVA. RESULTS: Postexercise forced expiratory volume in the first second (FEV1) and maximal mid-expiratory flow (MMEF) values as percent predicted (% pred) showed significant reductions over time (P < 0.001), significant differences among the four experimental conditions (P < 0.001) and a significant condition x time interaction (FEV1:P < 0.001, MMEF:P < 0.01). FEV1 was significantly lower for CC and WC, as compared with WW and CW at 5 and 10 min postexercise. The lowest postexercise values for FEV1 occurred in the CC and WC sessions (76% predicted in both). A similar pattern was obtained for MMEF. CONCLUSION: Facial cooling combined with either cold or warm air inhalation causes the greatest EIB, as compared with the isolated challenge with cold air inhalation. We suggest that vagal mechanisms play a major role in exercise and cold-induced bronchoconstriction.

Do gender differences in running performance disappear with distance?

It has been suggested that gender differences in running should disappear as distances increase, particularly past the marathon. This suggestion is primarily based on differences in fuel utilization, muscle damage following exercise, relative improvements in performance over the past decades, and on the analysis of marathon vs. ultramarathon performances of men and women. We reasoned that the best comparison of the potential of a human is by the use of world best times, which should be reasonable indicators of the effect of distance on relative performance of women and men. We compared current world best running performances at distances from 100 m to 200 km. Records as of December 2002 were obtained. T-tests analyzed speed differences between genders, and regression analysis tested the percent differences between men and women across distance. Speeds were different, with the average difference being 12.4% faster for men. There was a significant slope to the speed difference across distances in that longer distances were associated with greater differences. These results may be confounded by the reduced number of women in longer distance events. Furthermore, the proposed metabolic advantage for women because of increased fat metabolism may be masked by regular feeding during endurance races.

Predicting responses to sexually aggressive stories: the role of consent, interest in sexual aggression, and overall sexual interest.

Measures of interest in sexual aggression and overall sexual interest were used to predict men s responses to consensual and nonconsensual stories that contained forceful sexual content. College males (N = 108) listened to these stories and completed questionnaires assessing self-reported sexual arousal and desire, their perceptions of the woman s enjoyment and sexual desire in the stories, their likelihood of acting like the man in the stories, and how likely they would be to read similar stories. Multiple regression analyses revealed that overall sexual interest variables were significant predictors of responses to both consensual and nonconsensual stories, while interest in sexual aggression predicted responses to only the nonconsensual story. The present study highlights the importance of considering overall sexual interest measures in sexual aggression research.