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At least 433 records · Page 24Linked to original sources
PubMed2003

Soyasapogenol A and B distribution in soybean (Glycine max L. Merr.) in relation to seed physiology, genetic variability, and growing location.

An efficient analytical method utilizing high-performance liquid chromatography (HPLC)/evaporative light scattering detector (ELSD) was developed to isolate and quantify the two major soyasaponin aglycones or precursors in soybeans, triterpene soyasapogenol A and B. Soaking of seeds in water up to 15 h did not change the content of soyasapogenols. Seed germination had no influence on soyasapogenol A content but increased the accumulation of soyasapogenol B. Soyasapogenols were mainly concentrated in the axis of the seeds as compared with the cotyledons and seed coat. In the seedling, the root (radicle) contained the highest concentration of soyasapogenol A, while the plumule had the greatest amounts of soyasapogenol B. In 10 advanced food-grade soybean cultivars grown in four locations in Ontario, total soyasapogenol content in soybeans was 2 +/- 0.3 mg/g. Soyasapogenol B content (1.5 +/- 0.27 mg/g) was 2.5-4.5-fold higher than soyasapogenol A content (0.49 +/- 0.1 mg/g). A significant variation in soyasapogenol content was observed among cultivars and growing locations. There was no significant correlation between the content of soyasapogenols and the total isoflavone aglycones.

Germination↗
PubMed2003

Abdominal insufflation for prevention of exsanguination.

BACKGROUND: Currently, traumatic intra-abdominal hemorrhage continues unchecked during transport and triage, and a simple technique of prehospital hemostasis might improve outcomes. The hemostatic effect of abdominal hypertension has not been studied. PURPOSE: To examine the effect of iatrogenic abdominal insufflation on blood loss and hemodynamic performance after major abdominal vascular injury. METHODS: Following laparotomy, a 2.7 mm hole was created in the inferior vena cava of 10 anticoagulated pigs and controlled with a partially occlusive, laparoscopic vascular clamp. After abdominal closure the clamp was released and the pig was randomized to either control (n = 5) or immediate abdominal CO2 insufflation at 20 cm H2O pressure (n = 5). Lactated Ringer's solution was used as needed to maintain a mean arterial pressure of 60 mm Hg. After 15 minutes of hemorrhage and hemodynamic monitoring, the animals were killed and blood loss measured. Mean blood loss was compared between groups using the Student test, as were final values for physiologic variables. Temporal changes in physiologic parameters were compared using analysis of variance. RESULTS: Mean blood loss was reduced by 61% in insufflated pigs versus controls (695 +/- 244 versus 1764 +/- 328 cc, p < 0.001). Compared with controls, insufflated pigs had significantly higher mean arterial pressure (64 versus 25 mm Hg, p < 0.001), end-tidal CO2 (40.8 versus 17.8 mm Hg, p < 0.001), and pulmonary capillary wedge pressure (10.2 versus 5.8 mm Hg, p = 0.026) immediately before the pigs were killed. CONCLUSION: Iatrogenic abdominal insufflation significantly decreased blood loss and improved hemodynamics in a porcine model of traumatic venous hemorrhage. Iatrogenic abdominal insufflation may be useful in the prehospital management of abdominal injury.

Animals↗
PubMed2004

A comparison of biologically variable ventilation to recruitment manoeuvres in a porcine model of acute lung injury.

BACKGROUND: Biologically variable ventilation (return of physiological variability in rate and tidal volume using a computer-controller) was compared to control mode ventilation with and without a recruitment manoeuvre - 40 cm H2O for 40 sec performed hourly; in a porcine oleic acid acute lung injury model. METHODS: We compared gas exchange, respiratory mechanics, and measured bronchoalveolar fluid for inflammatory cytokines, cell counts and surfactant function. Lung injury was scored by light microscopy. Pigs received mechanical ventilation (FIO2 = 0.3; PEEP 5 cm H2O) in control mode until PaO2 decreased to 60 mm Hg with oleic acid infusion (PaO2/FIO2 <200 mm Hg). Additional PEEP to 10 cm H2O was added after injury. Animals were randomized to one of the 3 modes of ventilation and followed for 5 hr after injury. RESULTS: PaO2 and respiratory system compliance was significantly greater with biologically variable ventilation compared to the other 2 groups. Mean and mean peak airway pressures were also lower. There were no differences in cell counts in bronchoalveolar fluid by flow cytometry, or interleukin-8 and -10 levels between groups. Lung injury scoring revealed no difference between groups in the regions examined. No differences in surfactant function were seen between groups by capillary surfactometry. CONCLUSIONS: In this porcine model of acute lung injury, various indices to measure injury or inflammation did not differ between the 3 approaches to ventilation. However, when using a low tidal volume strategy with moderate levels of PEEP, sustained improvements in arterial oxygen tension and respiratory system compliance were only seen with BVV when compared to CMV or CMV with a recruitment manoeuvre.

Acute Disease↗
PubMed2003

[Analysis of variability in physiologic parameters using sequence plots].

The assessment of cardiovascular (and respiratory) parameters changes provides an information about the control systems involved and about their complex regulation. Methods based on nonlinear dynamics are able to quantify characteristics of the biosignal, that cannot be detected by conventional analysis methods. The sequence plot analysis is one of them. The aim of this paper is to provide basic information about this simple method and its application in the physiological research and in the clinical practice.

Analysis of Variance↗
PubMed2004

Uptake distribution of ozone in human lungs: intersubject variability in physiologic response.

The primary hypothesis of this study was that intersubject variation in uptake of inhaled ozone causes corresponding variation in the resulting physiologic response. The second hypothesis was that differences in breathing pattern and lung anatomy induce differences in ozone uptake. Sixty healthy nonsmokers participated in three exposure protocols during which their minute ventilation was 30 L/min, corresponding to moderate exercise. For the intermittent bolus exposure to ozone (BO3*), we measured the penetration volume at which 50% of the bolus was taken up (VP50%). Before and after continuous clean air exposure (Ca) and continuous ozone exposure (CO3: 0.25 ppm ozone), we measured forced expiratory volume in 1 second (FEV1), calculated as the percent change after exposure relative to start of exposure [%FEV1]). We also measured the cross-sectional area of the peripheral lung (Ap) for carbon dioxide (CO2) diffusion, calculated as the percent change after exposure relative to start of exposure (%Ap). After the CO3 session, we also measured ozone uptake (as ozone uptake rate) and fractional ozone uptake efficiency. Uptake efficiency ranged from 0.70 to 0.98 among all subjects. It was inversely correlated with breathing frequency (P = 0.000) but was not correlated with conducting airways volume (P = 0.333). VP50% ranged from 67 to 135 mL among all subjects and was directly correlated with conducting airways volume (P = 0.000). These results indicate that overall ozone uptake was related to breathing frequency but not to airway size, whereas internal distribution of ozone shifted distally as airway size increased. Values of %FEV1 (mean +/- SD: -13.71 +/- 12.99) and %Ap (-7.80 +/- 9.34) were both significantly more negative (P = 0.000) in the CO3 session than in the Ca (control) session (-0.055 +/- 4.57 and 0.40 +/- 11.03, respectively). Ozone uptake rate correlated with individual %Ap (P = 0.008) but not with individual %FEV1 (P = 0.575). Nor were individual %Ap or %FEV1 correlated with VP50%. Therefore, ozone uptake did not explain intersubject differences in forced expiratory responses in this study, but it did partially explain differences in the cross-sectional area available for gas diffusion in the peripheral lung.

Adult↗
PubMed2005

Effect of chronic use of different propulsion systems in wheelchair design on the aerobic capacity of Indian users.

BACKGROUND & OBJECTIVE: The use of wheelchairs (WC) of ergonomically different propulsion mechanisms may influence the cardiorespiratory capacity of the WC user. The purpose of the present investigation was to observe the impact of chronic use of four ergonomically different propulsion systems and age of the WC users on their aerobic capacity. METHODS: The male subjects (n=77), exclusively using hand rim (n=20), arm crank using both arms (n=22), arm crank using one arm (n=17), and arm lever using one arm (n=18) propelled WCs and 20 able-bodied (AB) subjects as the control group participated They performed maximal exercise test in continuous, step-wise incremental workload at a crank rate of 50 rpm on an arm-crank ergometer. The VO(2) and heart rate obtained during 2.45 to 3 min of each test exercise, and VO(2max) and HR(max) were derived respectively. Two-way ANOVA and multiple comparison tests were performed to compare the groups with respect to VO(2max) and HR(max). Age was used as a classificatory variable. RESULTS: The maximal physiological response of the AB subjects was superior to the WC users but the WC user groups did not show any significant differences amongst them. The aerobic capacity decreased with advancement of age and for WC users this is more pronounced. Equations for age predicted VO(2max) and HR(max) were also derived. INTERPRETATION & CONCLUSION: As the WC users used the four distinct propulsion systems, it was anticipated that it would induce variation in the physiological variables of the users. But the results of the study revealed that there was no significant difference. Suggesting that the WC users might have developed certain self-regulatory mechanisms in order to overcome the variation induced by the different propulsion systems.

Analysis of Variance↗
PubMedDate not supplied

Alterations in circadian excretion of urinary variables and physiological indicators of stress following surgery.

Alterations in level, timing, and coupling of circadian excretion of catecholamine metabolites, adrenal cortical hormones, sodium, potassium, creatinine, and vital signs in acute-care surgical patients were measured. Data were examined to determine if a relationship exists between the degree of circadian alteration and the subject's reentrainment to typical circadian profiles. Urine samples for assay, temperature, heart rate, and blood pressure were collected daily at 2-hour intervals from 11 consenting surgery subjects and 10 age- and sex-matched control subjects. The data indicate that certain circadian rhythms of hospitalized subjects were altered and uncoupled from external stimuli. These findings suggest that nurses (1) give individualized patient care to promote reentrainment recovery; and (2) refine nursing assessment to consider individual circadian patterns.

17-Ketosteroids↗
PubMed1985

Psychophysiological response specificities: a replication over a 12-month period.

A sample of 58 students was subjected to four stress conditions (mental arithmetic, reaction time, free speech, cold-pressor test). Eight physiological variables (skin conductance, heart rate, pulse amplitude, Heather index, eye blinking, horizontal eye movements, respiration rate, blood pressure) and five psychological variables (self-rated anger, irritability, tenseness, motivation, indifference) were monitored. Proportions of variance in a three-factor ANOVA (subjects, situations, variables) accounted for by individual specific response patterns (ISR) amounted to 33-40% for physiological and 9-13% for psychological variables. Stimulus specific response patterns (SSR) accounted for 11-19% for physiological and 8-14% for psychological variables, and motivation specific response patterns (MSR) for 17% for physiological and 14-16% for psychological variables. About one-fourth of the subjects showed a rather stable ISR in physiological variables when tested again after two months, and about 14% when tested again after twelve months. Overall, the results replicated earlier findings from this laboratory.

Adaptation, Physiological↗
PubMedDate not supplied

Physiological and psychological variables related to functional status in chronic obstructive pulmonary disease.

The relationship of selected physiological and psychological variables to functional status in patients with chronic obstructive pulmonary disease (COPD) was investigated in this study. There has been limited exploration of the relative contribution of these variables to the performance of activities of daily living in this population. A convenience sample of 104 outpatients with COPD participated in the study. The independent variables were causal attributions, depressed mood, self-esteem, pulmonary function, and exercise capacity, and the dependent variable was functional status. There was a significant difference in functional status between those who did and those who did not ask the question, "Why me?" (p = .03). In addition, the remaining psychological variables and both physiological variables were significantly correlated with functional status (p less than or equal to .01). To identify the combination of study variables most predictive of functional status a multiple regression analysis was performed. The combined variables of exercise capacity and depression best predicted functional status (p less than .0001). It is concluded that both physiological and psychological factors are important in understanding functional status in this population.

Activities of Daily Living↗
PubMed1999

Physiological and psychometric variables for monitoring recovery during tapering for major competition.

PURPOSE: This study attempted to identify variables that are useful in monitoring recovery during tapering. METHODS: Changes in physiological variables, tethered swimming force, mood states, and self-ratings of well-being were measured in 10 elite swimmers from before to after 2 wk of tapering for national championships. Physiological measures included resting heart rate (HR); blood pressure (BP); blood lactate concentration; red blood cell, white blood cell, and differential counts; and plasma cortisol, free testosterone, and catecholamine concentrations. Measures taken after 100-m maximal and 200-m standardized submaximal swims included HR, BP, and blood lactate concentration. RESULTS: Step-down regression analysis showed that changes in plasma norepinephrine concentration, heart rate after maximal effort swimming and confusion as measured by the Profile of Mood States (POMS) predicted the change in swimming time with tapering (r2 = 0.98); the change in plasma norepinephrine concentration predicted the change in swim time with tapering (r2 = 0.82) by itself. CONCLUSION: These data suggest that recovery after intense training can be monitored during tapering and that an accurate prediction of performance changes may be possible if the changes in a range of physiological and psychological variables are measured.

Adolescent↗