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Biomedical subjects

C E Wade

Publications and source records attributed to C E Wade.

At least 145 records · Page 8Linked to original sources
PubMed1981

Development of of pseudoanemia in marathon runners during a 20-day road race.

We measured RBC count, blood hemoglobin concentration, and related hematologic factors in 12 male marathon runners during a 20-day, 312-mile road race. The RBC and hemoglobin levels decreased significantly, from 5.17 million per cubic millimeter and 16.0 g/dL, respectively, to 4.36 million per cubic millimeter and 13.4 g/dL. Although the runners became marginally anemic during the race, their running speeds were not significantly changed. There were no abnormal clinical signs other than rare instances of hematuria. This study indicates that a sudden increase in long-distance running mileage above the regular training level may cause "sports anemia," a functional pseudoanemia that, in mild cases, does not impair endurance performance.

Adult↗
PubMed1981

Renal function, aldosterone, and vasopressin excretion following repeated long-distance running.

Renal and endocrine responses were studied in 10 male runners during a 20-day 500-km race. Overnight urine and prerun blood samples were taken prior to running on days 1, 2, 5, 8, 14, 17, and 20. Day 13 followed 70 h of rest. Urine flow rate, osmotic clearance, tubular free water reabsorption, urinary vasopressin excretion rate, and body weight were not significantly changed. Creatinine clearance was constant except for an elevation on day 5. Plasma osmolality was elevated on days 2, 14, and 17. Plasma sodium was increased (P less than 0.05) on days 2 and 13 but reduced on day 20. The percentage of filtered sodium excreted was significantly reduced on all nights following running and elevated on recovery day 13. Urinary aldosterone excretion rate was significantly elevated 162, 117, and 97% on days 5, 8, and 20 and returned to control levels on day 13 after 70 h of rest. These data suggest that in response to repeated long-distance running normal fluid balance is regained within 12 h. However, it is necessary to conserve sodium for at least 24 h after exercise as evidenced by the decrease in the percent filtered sodium excreted and continued elevation of aldosterone excretion.

Adult↗
PubMed1980

Plasma renin activity, vasopressin concentration, and urinary excretory responses to exercise in men.

Plasma vasopressin concentration (PAVP), renal function, and effectors of vasopressin release were evaluated in male volunteers during running at heart rates of 0, 35, 70, and 100% of maximum after 10 h abstinence from water (normal hydration) and at 100% after ingestion of 300 ml water. Plasma renin activity (PRA) and PAVP were linearly correlated and correlated to work intensity over all observations. Changes in PAVP were not correlated with changes in plasma osmolality (POSMOL) and plasma volume (PV) over all observations. Furthermore, despite similar changes in POSMOL, PV, PRA, body weight, mean arterial pressure, and plasma lactate concentration, the increase in PAVP after maximal exercise was greater during normal hydration than the water-supplemented state. Decreased urine flow observed in association with exercise was characterized by increased free water and decreased osmotic and creatinine clearances. Thus increased PAVP associated with exercise appears not to play a role in the concomitant antidiuresis. Vasopressin stimuli are probably variable at different times during exercise and may include factors other than those measured.

Adult↗
PubMed1980

Subchronic toxicity of acrylamide administered to rats in the drinking water followed by up to 144 days of recovery.

Groups of male and female Fischer 344 rats were administered acrylamide in their drinking water at 0, 0.05, 0.2, 1, 5, or 20 mg/kg/day for up to 93 days. Following the administration of acrylamide in the drinking water, male rats from each dose level were held for up to 144 days of recovery. The 20 mg/kg/day groups had definite treatment-related effects after 92 (males) and 93 (females) days. They were dragging the rear limbs, body weights were decreased, serum cholinesterase activity was decreased in top dose females, and packed cell volume, red blood cell, and hemoglobin values were slightly decreased in males and females. In the 20 mg/kg/day groups, the primary target tissue was the peripheral nerve with lesions consisting of severe degeneration characterized by demyelinization and axonal loss. Slight spinal cord degeneration was observed. Other effects included atrophy of skeletal muscle, testicular atrophy, and distended urinary bladders; these were probably secondary to the nerve degeneration. After 144 days of recovery, the lesions had partially or completely reversed. Parameters affected at the 5 mg/kg/day dose level after 92 (males) and 93 (females) days consisted of peripheral nerve degeneration which were of a lesser degree of severity than those seen in the 20 mg/kg/day groups and appeared to have completely reversed after 111 days of recovery. In rats given 1 mg/kg/day, a minimal treatment-related effect was observed in males after 92 days, and this was limited to very slight nerve degeneration using electron microscopy (females were not examined by electron microscopy). This observed effect appeared to have reversed after 25 days of recovery. No treatment-related effects were seen in any of the parameters monitored in the rats given 0.05 or 0.2 mg/kg/day of acrylamide.

Acrylamides↗
PubMed1979

Regional heat loss in resting man during immersion in 25.2 degrees C water.

Five male subjects having a wide range of relative body fat, 9.2-20.2%, were studied during total body immersion in water at 25.2 degrees C. The regional surface area of each subject was calculated from anthropometric data utilizing a segmental geometric model. Skin temperatures (Tsk) and regional skin heat loss were measured prior to and during 30 min immersion at 13 sites. During immersion, mean Tsk was 25.9 degrees C and remained significantly higher than the water temperature. A measurable temperature gradient for heat flow was observed from all body segments. Segimental temperature in water ranged from 26.7-25.4 degrees C, being warmest at the neck and coolest at the foot. Heat the flow per regional area was highest in the neck, 187 W/m2, and least at the foot, 12 W/m2. Heat flow from each body region was dependent on regional Tsk. Skinfold thickness was a minor factor in altering regional heat flow in the foot, hand, lower arm, upper arm, thigh, and calf; in the torso, neck, and head regions it was of major importance in detering heat loss.

Adult↗
PubMed1979

Absence of antiarrhythmic effects of helium in patients with spontaneous premature ventricular beats at rest.

Six patients with spontaneously occurring arrhythmias were studied to assess the antiarrhythmic properties of helium. The patients were divided into two subgroups breathing air, helium-oxygen (heliox), and nitrogen-oxygen (nitrox) in an alternating sequence during successive 20-min periods under continuous ECG surveillance at rest. There were no significant reductions in spontaneously occurring premature ventricular beats while breathing heliox, compared to breathing air of nitrox. Alternating the breathing gases in this manner caused no change in plasma concentration of electrolytes or in activity of serum glutamic-oxaloacetic transaminase or lactic acid dehydrogenase. We conclude that helium does not affect spontaneously occurring chronic premature ventricular beats in conscious resting man when it is breathed for a period of up to 20 min.

Adult↗
PubMed1977

Combined effects of breathing resistance and hyperoxia on aerobic work tolerance.

Effects of three curvilinear inspiratory resistances (R1, R2, R3) on the cardiorespiratory responses of seven well-trained men during incremental cycling tests to exhaustion were studied by comparison to the low resistance R0 (at 1 l/s, R0 = 0.2; R3 = 6.5 cmH2O-s/l). Submaximal VO2 and the gas exchange anaerobic threshold (AT) were not affected by increasing resistance. Although maximal work rates were not significantly changed, highly significant reductions were observed for VE (R0 = 166.3; R3 = 99.7 l/min BTPS), VO2 max (R0 = 4,26; R3 = 3.74 l/min), HR (R0 = 185; R3 = 176 beats/min), and endurance (R0 = 17.3; R3 = 15.5 min) suggesting that aerobic work tolerance was dependent on ventilatory capacity. In additional tests removal of R3 at exhaustion abruptly increased VE and VO2, and permitted work to continue. Ventilation and work tolerance were therefore limited by R3 before the legs fatigued. Breathing 35% O2 against R3 produced significant, although small, increases in AT, VO2 max, peak HR, and endurance while decreasing the hyperventilatory response to work above AT. Thus, aerobic work tolerance reduced with high inspiratory resistance was partly restored by moderate hyperoxia, apparently because the ventilatory limit was delayed.

Airway Resistance↗
PubMed1977

Chronic toxicity and reproduction studies of hexachlorobutadiene in rats.

Hexachlorobutadiene (HCBD), while not produced commercially in the United States, may be encountered as an unwanted by-product of certain processes associated with the chlorination of hydrocarbons. Studies were conducted to assess the potential long-term toxicity of HCBD. In a reproduction study conducted in rats, dose levels of 20 or 2.0 mg/kg-day of HCBD induced slight maternal toxicity (primarily of the kidney) but caused no adverse effects on reproductive parameters-percent pregnancy and neonatal survival/development. A decreased neonatal body weight was noted at the highest dose level of 20 mg/kg-day of HCBD. No toxicologic effects were observed among the adults at a dose level of 0.2 mg/kg-day or among the neonates at dose levels of 0.2 or 2.0 mg/kg-day of HCBD. In a chronic toxicity study in rats, ingestion of 20 mg/kg-day for up to 2 years caused multiple toxicologic effects, primarily of the kidney, including the development of renal tubular adenomas and adenocarcinomas. Ingestion of the intermediate dose level of 2 mg/kg-day caused lesser degrees of toxicity, but no evidence of neoplasia. Ingestion of the lowest dose level of 0.2 mg/kg-day of HCBD caused no effects that could be attributed to treatment. These data indicate a dose-response relationship for HCBD-induced toxicity affecting primarily the kidney. HCBD-induced neoplasms occurred only at a dose level higher than that causing discernible renal injury.

Adenocarcinoma↗
PubMed1977

Thermographic evaluation of the relative heat loss by area in man after swimming.

Regional differences in skin temperature (Ts) were determined by infrared radiography in four competitive swimmers of varying body compositions, prior to, after 5 min of immersion in water (Tw) at 23.5 degrees C, and after a 500-m freestyle swim at a training pace. Decreases in skin temperature that correlated with skinfold thickness were seen post-immersion (r = 0.56, p less than 0.05). After swimming, skin temperatures were highest in regions overlying active muscle masses and were independent of skinfold thickness. These regions were the deltoids, trapezius, triceps and biceps brachi, and pectorals. Swimming increased the extent of warmer skin surface areas and gradient Ts-Tw, over which heat loss could occur.

Adolescent↗
PubMed1976

Elevated urinary phenol levels in beagle dogs treated with salol.

Dogs administered 500 or 250 mg of salol/kg/day showed transient toxicity of a reversible nature. Doses of 125 mg salol/kg/day caused no discernible ill effects in spite of urinary phenol levels elevated as high as 6144 ppm. It appears as if exposure to a compound other than benzene can cause an elevation of urinary phenol.

Animals↗
PubMedDate not supplied

Acute and subacute toxicity of 7.5% hypertonic saline-6% dextran-70 (HSD) in dogs. 2. Biochemical and behavioral responses.

7.5% Hypertonic saline-6% Dextran-70 (HSD) is currently being evaluated in our laboratory as a resuscitation solution for the treatment of hypovolemia at a dose of 4 ml kg-1 body weight. A few reports of dextran toxicity, particularly of the kidney, have been cited in the literature, so the present study evaluated the acute and subacute toxicity of HSD administered i.v. to beagle dogs. In the acute toxicity studies animals were infused with a single dose of HSD, or its components of hypertonic saline (HS) or Dextran-70 (D-70), at the maximum tolerated dose (MTD: 20 ml kg-1). Controls received Ringers lactate (RL). In the HSD-infused dogs, transient but significant increases in serum alanine (ala) aminotransferase (AT), aspartate (asp) AT and alkaline phosphatase (AP) were observed for the first 72 h. In most cases this increase was also observed in the HS group. In the subacute studies, dogs were infused daily with the MTD of the above test solutions. Serum ala AT activity was 2-3-fold higher in the HSD than the RL group for the first 3 days. Again, a similar effect was observed in the HS group. Slight, transient increases in asp AT and AP activity were also observed in the HSD group. Higher lactate dehydrogenase (LDH) activity was only observed at Day 14 in dogs infused with the MTD of HSD or HS. In both studies, no adverse effects on blood urea nitrogen (BUN) or serum creatinine were observed and other transient changes in serum parameters were attributable to hemodilution induced by HSD.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMedDate not supplied

A chronic toxicity and oncogenicity study in rats and subchronic toxicity study in dogs on ingested vinylidene chloride.

The chronic toxicity and oncogenic potential of ingested vinylidene chloride (VDC) was evaluated in a 2-year study on Sprague-Dawley rats and the subchronic toxicity was evaluated in beagle dogs in a 97-day study. The vinylidene chloride was incorporated in the drinking water of the rats at nominal concentrations of 50, 100 or 200 ppm. The time weighted average mg/kg body weight/day dosages of vinylidene chloride administered to the male and female rats over the 2-year period at the various mean analyzed concentrations were 7, 10 or 20 for the males and 9, 14 or 30 for the females. Dogs were administered vinylidene chloride in peanut oil incorporated in a gelatin capsule at concentrations which provided 6.25, 12.5 or 25 mg vinylidene chloride/kg body weight/day. There were no significant differences between the groups of rats or dogs ingesting vinylidene chloride and their corresponding control groups in the following parameters: appearance and demeanor, mortality, body weight, food consumption, hematology, urinalysis, clinical chemistry determinations, organ weights and organ to body weight ratios. There were no significant differences in water consumption of the groups of rats ingesting vinylidene chloride and the controls. The sole treatment-related observation in the rats, evident only upon microscopic examination, was in the liver. The observation was characterized by a minimal amount of hepatocellular swelling with midzonal fatty change which occurred in the females at all dose levels and in the males only at the 200 ppm level. No exposure-related neoplastic changes occurred in the rats in any of the test groups. No exposure-related gross or histopathological changes were present in the tissues taken from the dogs at the termination of the 97-day study.

Animals↗