Biomedical subjects

A Utter

Publications and source records attributed to A Utter.

12 recordsLinked to original sources

PubMed1998

Carbohydrate supplementation and the lymphocyte proliferative response to long endurance running.

This randomized, double-blind, placebo-controlled study examined the influence of 6% carbohydrate ingestion on hormonal and lymphocyte proliferative responses (5 total samples over 9 hours) to 2.5 h of high-intensity running by 30 experienced marathon runners. The T-cell response differed between groups, with the placebo group exhibiting a greater increase immediately post-run and greater decrease at 3 h of recovery. No group differences were observed for Con A-, PHA-, or PWM-induced lymphocyte proliferation. However, when PHA was adjusted per T-cell, group differences were observed, highlighted by a decrease in the placebo group immediately post-run. Glucose and cortisol responses differed between groups, with glucose lower and cortisol higher in the placebo group immediately post-run. Post-run glucose correlated negatively with postrun cortisol (r=-0.670, P< 0.001) and epinephrine (r=-0.540, P=0.002). Post-run cortisol also correlated negatively with total lymphocytes and T-cells at 1.5 hours (r=-0.429, P=0.018 and r=-0.424, P=0.019, respectively) and 3 hours (r=-0.566, P=0.001 and r=-0.523, P=0.003, respectively) of recovery. The pre- to post-run change in glucose correlated to the same changes in PHA/T-cell (r=0.456, P=0.011). The data support an interactive effect of carbohydrate ingestion on plasma glucose and cortisol. The data support an interactive effect of carbohydrate ingestion on plasma glucose and cortisol, T-cell trafficking, and cell-adjusted PHA-induced lymphocyte proliferation following long endurance running.

Adult↗

PubMed1998

Influence of mode and carbohydrate on the cytokine response to heavy exertion.

OBJECTIVE AND METHODS: This randomized, double-blind, placebo-controlled study was designed to determine the influence of exercise mode and 6% carbohydrate (C) versus placebo (P) beverage ingestion, on blood cell counts, plasma glucose, hormone, and inflammatory cytokine responses (five total samples over 9 h) to 2.5 h of high-intensity running and cycling (approximately 75% VO2max) by 10 triathletes who acted as their own controls. Statistical significance was set at P < or = 0.05. RESULTS: C relative to P ingestion (but not exercise mode) was associated with higher plasma levels of glucose and insulin, lower plasma cortisol and growth hormone, and diminished perturbation in blood immune cell counts. The pattern of change over time for interleukin (IL)-6 was significantly different between C and P conditions (P = 0.021) and between running and cycling modes (P < 0.001), with the lowest postexercise values seen in the C-cycling sessions (10.7 +/- 1.8 pg x mL(-1)) and the highest in the P-running sessions (51.6 +/- 14.2 pg x mL(-1)). The pattern of change over time between C and P conditions (but not modes) was significantly different for IL-1 receptor antagonist (P = 0.003), with values once again lowest for the C-cycling sessions (1.5 h postexercise, 301 +/- 114 pg x mL(-1)) and highest for the P-running sessions (1171 +/- 439 pg x mL(-1)). CONCLUSION: These data indicate that carbohydrate versus placebo ingestion (4 mL x kg(-1) carbohydrate or placebo every 15 min of the 2.5-h exercise bout) is associated with higher plasma glucose levels, an attenuated cortisol response, and a diminished pro- and anti-inflammatory cytokine response.

Adult↗

PubMed1998

Immune response to exercise training and/or energy restriction in obese women.

PURPOSE: The effect of exercise training (five 45-min walking sessions/wk at 60-75% maximum heart rate) and/or moderate energy restriction (4.19-5.44 MJ or 1,200-1,300 kcal x d(-1)) on innate and adaptive immunity (including mitogen-stimulated lymphocyte proliferation (MSLP), natural killer cell activity (NKCA), and monocyte and granulocyte phagocytosis and oxidative burst (MGPOB) was studied in obese women (N = 91, age 45.6 +/- 1.1 yr, body mass index 33.1 +/- 0.6 kg x m(-2)) randomized to one of four groups: control (C), exercise (E), diet (D), exercise, and diet (ED). METHODS: Aerobic power, body composition, and immune function were measured in all subjects before and after a 12-wk diet intervention period, with data analyzed using a 4 x 2 repeated measures design. All subjects self-reported symptoms of sickness in health logs using a precoded checklist. Statistical significance was set at P < or = 0.05. RESULTS: Data from this study indicate that although exercise training was unrelated to any significant changes in resting immune function, the number of days with symptoms of upper respiratory tract infection (URTI) was reduced relative to subjects in the nonexercise groups (5.6 +/- 0.9 and 9.4 +/- 1.1 sickness days, respectively, P < 0.05). Energy restriction and weight loss (7.9 +/- 0.7 kg) was associated with a significant decrease in MSLP, but no change in NKCA, MGPOB, or URTI. CONCLUSION: The data are consistent the viewpoint that weight loss, even at a moderate rate, is associated with a decrease in mitogen-stimulated lymphocyte proliferation without a change in various measures of innate immunity of the blood compartment.

Adult↗

PubMed1998

Effects of mode and carbohydrate on the granulocyte and monocyte response to intensive, prolonged exercise.

The influence of exercise mode and 6% carbohydrate (C) vs. placebo (P) beverage ingestion on granulocyte and monocyte phagocytosis and oxidative burst activity (GMPOB) after prolonged and intensive exertion was measured in 10 triathletes. The triathletes acted as their own controls and ran or cycled for 2.5 h at approximately 75% maximal O2 uptake, ingesting C or P (4 total sessions, random order, with beverages administered in double-blind fashion). During the 2. 5-h exercise bouts, C or P (4 ml/kg) was ingested every 15 min. Five blood samples were collected (15 min before exercise, immediately after exercise, and 1.5, 3, and 6 h after exercise). The pattern of change over time for GMPOB was significantly different between C and P conditions (P </= 0.05), with postexercise values lower during the C trials. Little difference was measured between running and cycling modes. C relative to P ingestion (but not exercise mode) was associated with higher plasma levels of glucose and insulin, lower plasma levels of cortisol and growth hormone, and lower blood neutrophil and monocyte cell counts. These data indicate that C vs. P ingestion is associated with higher plasma glucose levels, an attenuated cortisol response, and lower GMPOB.

Adult↗

PubMed1997

Insulin and glucagon immunoreactivity during high-intensity exercise under opiate blockade.

Eight fit men [maximum oxygen consumption (VO2max) 64.6 (1.9) ml x kg(-1)xmin(-1), aged 28.3 (1.7) years (SE in parentheses) were studied during two treadmill exercise trials to determine the effect of endogenous opioids on insulin and glucagon immunoreactivity during intense exercise (80% VO2max). A double-blind experimental design was used with subjects undertaking the two exercise trials in counterbalanced order. Exercise trials were 20 min in duration and were conducted 7 days apart. One exercise trial was undertaken following administration of naloxone (N; 1.2 mg; 3 ml) and the other after receiving a placebo (P; 0.9% NaCl saline; 3 ml). Prior to each experimental trial a flexible catheter was placed into an antecubital vein and baseline blood samples were collected. Immediately after, each subject received either a N or P bolus injection. Blood samples were also collected after 20 min of continuous exercise (running). Glucagon was higher (P < 0.05), while insulin was lower (P < 0.05), during exercise compared with pre-exercise values in both trials. However, glucagon was higher (P < 0.05) in the P than in the N exercise trial [141.4 (8.3) ng x 1(-1) vs 127.2 (7.6) ng x 1(-1)]. There were no differences in insulin during exercise between the P and N trials [50.2 (4.3) pmol x 1(-1) vs 43.8 (5) pmol x 1(-1)]. These data suggest that endogenous opioids may augment the glucagon response during intense exercise.

Adult↗

PubMed1997

Carbohydrate supplementation affects blood granulocyte and monocyte trafficking but not function after 2.5 h or running.

This randomized, double-blind, placebo-controlled study was designed to determine the influence of carbohydrate supplementation on the granulocyte and monocyte response to 2.5 h of high-intensity running [76.7 +/- 0.4% of maximal oxygen consumption (VO2max)]. Thirty experienced marathon runners (VO2max 53.4 +/- 1.0 mL.kg-1.min-1, age 41.5 +/- 1.4 y) were randomly assigned to carbohydrate-supplement (n = 17) and placebo (n = 13) groups. Subjects rested for 10-15 min before a blood sample was taken at 0715, and then ingested 0.75 L carbohydrate beverage or placebo. At 0730 subjects began running at 75-80% of VO2max for 2.5 h, and drank 0.25 L carbohydrate or placebo fluid every 15 min. Immediately after the 2.5-h run (1000), another blood sample was taken, followed by 1.5-h, 3-h, and 6-h recovery samples. Carbohydrate supplementation had a significant effect compared with placebo on the pattern of change in plasma glucose and cortisol, and the blood concentration of neutrophils (F[14, 112] = 5.13, P = 0.001) and monocytes (F[14, 112] = 4.78, P = 0.001), but not on blood granulocyte and monocyte phagocytosis or oxidative burst activity after 2.5 h of intensive running.

Adult↗

PubMed1997

Carbohydrate affects natural killer cell redistribution but not activity after running.

This randomized, double-blind, placebo-controlled study was designed to determine the influence of carbohydrate supplementation on the natural killer cell response to 2.5 h of high-intensity running (76.7 +/- 0.4% VO2max). Thirty experienced marathon runners (VO2max 53.4 +/- 1.0 mL x kg[-1] x min[-1], age 41.5 +/- 1.4 yr) were randomized into carbohydrate supplement (N = 17) and placebo (N = 13) groups. Subjects rested for 10-15 min before a blood sample at 0715, and then ingested 0.75 L of carbohydrate beverage (Gatorade) or placebo. At 0730, subjects began running at 75-80% VO2max for 2.5 h and drank 0.25 L of carbohydrate or placebo fluid every 15 min. Immediately after the 2.5 h run (1000), another blood sample was taken, followed by 1.5 h, 3 h, and 6-h recovery samples. Carbohydrate supplementation versus placebo had a significant effect on the pattern of change in glucose, cortisol, and the blood concentration of natural killer cells ([F (4,25) = 3.79, P = 0.015], but not natural killer cell activity following 2.5 h of intensive running.

Adult↗

PubMed1997

Effect of carbohydrate substrate availability on ratings of perceived exertion during prolonged running.

The purpose of this study was to investigate the effects of carbohydrate substrate availability on ratings of perceived exertion (RPE) during prolonged submaximal running. Thirty marathon runners were recruited as subjects. A double-blind study design was used in which subjects performed an experimental trial that consisted of a 2.5-hr treadmill run at 75-80% VO2max. During the experimental trial, the subjects in the carbohydrate feeding group ingested a 6% glucose and fructose solution at a rate of approximately 60 g.hr, whereas subjects in the placebo group consumed an equal volume of artificially flavored placebo. Statistical analysis of RPE, respiratory exchange ratio, fat and carbohydrate oxidation rate, and blood glucose concentrations indicated that increased carbohydrate substrate availability attenuated the intensity of exertional perceptions during the later stages of prolonged running at 75-80% VO2max in marathon runners.

Adult↗

PubMed1997

Carbohydrate and the cytokine response to 2.5 h of running.

This randomized, double-blind, placebo-controlled study was designed to determine the influence of 6% carbohydrate (C) vs. placebo (P) beverage ingestion on cytokine responses (5 total samples over 9 h) to 2.5 h of high-intensity running (76.7 +/- 0.4% maximal O2 uptake) by 30 experienced marathon runners. For interleukin-6 (IL-6), a difference in the pattern of change between groups was found, highlighted by a greater increase in P vs. C immediately postrun (753 vs. 421%) and 1.5 h postrun (193 vs. 86%) [F(4,112) = 3.77, P = 0.006]. For interleukin-1-receptor antagonist (IL-1ra), a difference in the pattern of change between groups was found, highlighted by a greater increase in P vs. C 1.5 h postrun (231 vs. 72%) [F(2,50) = 6.38, P = 0.003]. No significant interaction effects were seen for bioactive IL-6 or IL-1 beta. The immediate postrun plasma glucose concentrations correlated negatively with those of plasma cortisol (r = -0.67, P < 0.001); postrun plasma cortisol (r = 0.70, P < 0.001) and IL-6 levels (r = 0.54, P = 0.003) correlated positively with levels of IL-1ra. Taken together, the data indicate that carbohydrate ingestion attenuates cytokine levels in the inflammatory cascade in response to heavy exertion.

Adult↗

PubMed1997

Exercise and gall bladder function.

Epidemiological research has demonstrated protective effects of varying strength from physical activity against the risk for several chronic diseases such as coronary heart disease, hypertension, non-insulin-dependent diabetes mellitus and osteoporosis. Epidemiological studies have been supported by experimental research showing that exercise training improves coronary heart disease risk factors and other health-related factors. In contrast, the association between physical activity, exercise and gall stone disease has not yet been firmly established. This paper presents the theoretical role of aerobic exercise: (i) in the primary prevention of gall stone disease; and (ii) as a potential prokinetic agent in high risk gall stone disease groups. Primary risk factors in the pathogenesis of gall stone formation include cholesterol supersaturation in the solutes that precipitate from bile, hypernucleation (measured as "crystal appearance time') and finally hypomotility of the gall bladder which allows bile stasis and crystal formation. While the results of epidemiological studies suggest that physical activity may be inversely associated with gall stone disease, the mechanisms by which exercise may influence gall stone disease pathogeneses are poorly understood. In this paper the association between physical activity and exercise to gall bladder function and gall stone disease will be examined. Recommendations for future research and the implications for the primary prevention of gall stone disease will also be discussed.

Cholelithiasis↗

PubMed1991

Evaluation of lymphoid-specific enhancer addition or substitution in a basic retrovirus vector.

Two novel retroviral vectors bearing lymphoid-specific enhancers were tested for improved expression of human adenosine deaminase (hADA) in tissue culture cells and in mouse bone marrow transplant recipients. These vectors carried either an added human T-cell receptor alpha-chain enhancer (delta N2TADA) or a substitution of the Moloney long terminal repeat (LTR) enhancer with the murine immunoglobulin mu heavy-chain first intron enhancer (delta N2 mu ADA). Each vector was produced at a titer of approximately 10(6) infectious units/ml and efficiently transduced hADA into murine fibroblast and myeloma cells in culture. No quantitative difference in expression was observed between the enhancer modified vectors and the basic retrovirus vector (delta N2ADA). In addition, each vector efficiently conferred hADA expression in lymphoid, myeloid, and erythroid cells of long-term transplanted mice. The majority of the transduced-marrow recipients demonstrated expression of the human enzyme for 4-8 months with each of the three vectors.

Adenosine Deaminase↗

PubMed1980

Effect of magnesium deficiency on erythrocyte aging in rats.

Rats placed on a magnesium-deficient diet show decreased erythrocyte magnesium concentration, shortened erythrocyte survival, and erythrocyte membrane ultrastructure defects and become progressively anemic. Whether these pathologic processes are due to abnormal erythropoiesis or occur in the peripheral circulation is unknown. In the present study, magnesium and hemoglobin concentrations, reticulocyte count, erythrocyte pyrophosphatase, and pyruvate kinase activities were determined at weekly intervals for 6 weeks in whole blood and age-dependent erythrocyte fractions isolated from inbred Fisher rats fed a diet deficient in magnesium or the same diet with added magnesium. Freeze-fracture electron microscopic examinations were performed on age-dependent erythrocyte fractions to evaluate the membrane defect. The youngest red cells from magnesium-deficient rats were similar to those of control animals with respect to erythrocyte magnesium concentrations, pyrophosphatase activities, and membrane morphology. The older erythrocyte fractions from magnesium-deficient rats showed significant decreases in magnesium concentrations, pyrophosphatase activity, and the presence of membrane abnormalities. Thus, new erythrocytes produced in magnesium-deficient rats appear to be normal but rapidly develop biochemical and morphologic abnormalities with aging in a magnesium-deficient plasma environment.

Animals↗