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Biomedical subjects

J Alexander

Publications and source records attributed to J Alexander.

At least 559 records · Page 31Linked to original sources
PubMed1981

Hepatobiliary transport and organ distribution of silver in the rat as influenced by selenite.

Bile from rats injected with 110mAgNO3 (1 micromol/kg) were fractionated on Sephadex G-15 revealing binding of silver to one high molecular weight substance and one low molecular weight substance eluting corresponding to the void volume and glutathione (GSH) respectively. Fractionation of AgNO3 and GSH mixed in vitro gave rise to a polynuclear complex and a 1 : 1 complex of Ag+-GSH which both eluted corresponding to silver in bile. Depletion of GSH in the liver by diethylmaleate (3.9 mmol/kg) caused a parallel decrease in the biliary excretion of both silver and reduced GSH. These findings support the hypothesis that silver is excreted into bile by a GSH-dependent mechanism most likely using GSH as a carrier molecule. Selenite (1 micromol/kg) inhibited the biliary excretion of silver while AgNO3 (1 mumol/kg) did not influence the excretion of selenium into bile. Pretreatment with selenite (1 micromol/kg) also caused a retention of silver (AgNO3, 1 micromol/kg) in the blood, kidney and brain. The liver content of silver was decreased and the organ to plasma ratio of silver was unchanged for erythrocytes, but decreased for the brain, kidney and liver, respectively. The effects caused by selenite are attributed to the formation of Ag2Se complexes which are nearly water insoluble and probably unavailable for biliary excretion. Selenium metabolites (GSSeSG, GSSeH) which are excreted into bile are probably not available for complexing with Ag+.

Animals↗
PubMed1981

Excretion of zinc in rat bile - a role of glutathione.

Fractionation of the bile from rats injected with 65ZnCl2 (5 mumol/kg) showed that zinc was mainly bound to low molecular weight compounds eluted corresponding to the zinc-glutathione complexes. Diethylmaleate (3.9 mmol/kg), cyclohexene oxide (4.9 mmol/kg) and acrylamide (3.5 mmol/kg) administered intraperitoneally to rats caused a rapid decrease in the endogenous excretion of both zinc and reduced glutathione into bile. This depression probably reflects the conjugation of the aforementioned substances to glutathione in the liver cells. These results indicate that zinc is transferred from liver to bile by glutathione dependent process and most likely as zinc-glutathione complexes.

Animals↗
PubMed1981

Exercise left ventricular performance in patients with chest pain, ischemic-appearing exercise electrocardiograms, and angiographically normal coronary arteries.

Left ventricular performance was evaluated using first-pass radionuclide angiocardiography in 31 patients with chest pain, an ischemic-appearing exercise electrocardiogram, and angiographically normal coronary arteries at rest and during maximal upright bicycle exercise. Thallium-201 (201 TI) imaging was done in all patients after treadmill exercise and in selected patients after ergonovine provocation. Resting left ventricular performance was normal in all patients. An abnormal ejection fraction response to exercise was detected in 12 of 31 patients. Regional dysfunction was present during exercise in four patients, all of whom also had abnormal global responses. Three of these 12 patients and two additional patients had exercise-induced 201 TI perfusion defects. In all nine patients who underwent ergonovine testing, there was no suggestion of coronary arterial spasm. Thus, left ventricular dysfunction during exercise, in the presence of normal resting performance, was found in a substantial number of patients with chest pain, an ischemic-appearing exercise electrocardiogram, and normal coronary arteries.

Adult↗
PubMed1981

Activities of daily living: reliability and validity of gross vs specific ratings.

The inter-rater reliability and criterion validity of gross vs specific ratings of activities of daily living (ADL) were compared. Forty-three physical therapy students rated 6 patients performing 16 ADL on videotape. With controls for tape order presentation and order of protocol use, specific ratings were found to be more reliable than gross ratings in terms of total scores, transfers, and personal hygiene activities. Dressing activities were found to be reliably rated on both protocols, but locomotion activities presented problems on both. In terms of criterion validity, both protocols significantly differentiated dependent, middle-range, and independent patients, but the gross ratings were significantly lower for dependent and middle-range patients than specific protocols. It was concluded that when activities can be broken down into independent task components, specific protocols are the assessment method of choice. When activities are made up of highly interdependent task components, a behaviorially anchored gross rating protocol may be more effective. Implications for further research are discussed.

Activities of Daily Living↗
PubMed1981

[Epidemiology of blood pressure in 4 Swiss cities].

Within the framework of the Swiss National Research Program for the Prevention of Cardiovascular Disease, blood pressure levels of 8140 adults were recorded in four Swiss cities. Repeated measurements yield lower results. The values increase with age and are higher in men than in women. Swiss citizens have higher mean values than foreigners, and values in the French-speaking cities are significantly higher than those of the German-speaking cities. The prevalence of hypertension also depends on sex and age. The prevalence of elevated values (less than or equal to 160/95 mm Hg) identified by measurement, standardized for sex, age and nationality, is 11.6%; if the known, treated hypertensives are included the prevalence is 14.2%. 55% of the hypertensives knew of their condition, 39% were under medical treatment and only 20% were well controlled (greater than 160/95 mm Hg). There were considerable differences between the two region; fewer of the hypertensives were known and fewer were under control in the French-speaking towns.

Adolescent↗
PubMed1981

[Physical activity and capacity in 4 Swiss cities].

As part of the Swiss National Research Program for the Prevention of Cardiovascular Disease, the degree of physical activity at work and during leisure time ws investigated in 3614 men and 4221 women living in four Swiss cities. Some 50% of the men and more than 60% of the women were considered insufficiently active. Since their jobs involve little physical activity, the quantity and quality of exercise needed for prevention of coronary heart disease can only be obtained from sports during leisure time. Of the men and women investigated in Aarau, 65 and 61% respectively volunteered for a bicycle ergometer test while in Nyon the participation in this part of the study was considerably lower (29 and 24% of the men and women). In both sexes and all age groups the mean values for the extrapolated maximum oxygen uptake were comparable to those reported from other highly industrialized countries.

Adolescent↗
PubMed1981

[Prevalence of exposure to cardiovascular risk factors in 4 Swiss cities].

Risk factors for cardiovascular diseases were measured in a sample of 3665 adults between 16 and 70 years of age in four Swiss cities. 54.7% of men and 37.6% of women had either blood pressure values above 160/95 mm Hg or smoked at least 8 g tobacco per day, or had plasma cholesterol exceeding 260 mg/dl (6.73 mmol/l). The statistical associations between the three factors were studied with the following results: direct relation between hypertension and hypercholesterolemia - the odd ratio standardized for age according to Mantel-Haenszel (ORmh) = 2.7 with a 95% confidence interval (IC95) = 1.8 to 4.1 - an inverse relation between hypertension and tobacco consumption - ORmh = 0.59, IC95 = 0.38 to 0.92. In order to investigate the variables associated with exposure to all three factors, an age-specific index of risk was calculated for each person using the multiple logistic function obtained in the Framingham study. In males, this index was elevated in subjects who were sedentary, obese and alcohol consumers, subjects who ate less than three meals a day and subjects who lived alone. The index was elevated in women who were obese, who ate less than three meals a day and in women living alone or without children. The mortality rate for ischemic heart diseases in the four towns was compared with known risk factors and with alcohol consumption. It appears that for both sexes the larger the population regularly drinking a moderate quantity of wine, the lower the mortality rate. The importance of a multifactorial approach to the prevention of cardiovascular diseases is emphasized.

Adolescent↗
PubMed1980

Awareness of cardiac function in anxious, phobic and hypochondriacal patients.

Awareness of pulse rate was tested in 60 psychiatric out-patients with anxiety, phobic or hypochondriacal neuroses by asking them to record how fast their hearts were beating during exposure to short film sequences. Correlations between subjective and objective heart rate (ECG) were significantly higher in anxious and hypochondriacal patients than in phobic ones. The results suggest that somatic symptoms in hypochondriacal and anxiety neurosis reflect increased awareness of bodily function.

Anxiety↗
PubMed1980

Vagal mediation of hypothalamic obesity but not of supermarket dietary obesity.

In two independent experiments, complete subdiaphragmatic vagotomy did not prevent the development of the obesity that results from the addition of highly palatable foods to the diet of rats. The vagotomized animals exhibited only a 1-day delay in the onset of overeating, and this only when first exposed to the tasty diet. In independent tests of the functional completeness of the vagotomies, the vagotomized animals failed to overeat or gain excessive weight on a standard laboratory diet following bilaterally parasagittal hypothalamic knife cuts. Thus, hypothalamic knife-cut obesity requires the integrity of the vagus for its full expression, whereas dietary obesity does not.

Animals↗
PubMed1980

Lyme carditis: cardiac abnormalities of Lyme disease.

We studied 20 patients, mostly young adult men, with cardiac involvement of Lyme disease. The commonest abnormality (18 patients) was fluctuating degrees of atrioventricular block; eight of them developed complete heart block. Thirteen patients had evidence of more diffuse cardiac involvement: electrocardiographic changes compatible with acute myopericarditis (11 patients), radionuclide evidence of mild left ventricular dysfunction (five of 12 patients tested), or frank cardiomegaly (one patient). Heart involvement was usually preceded by erythema chronicum migrans and sometimes accompanied by meningoencephalitis, facial palsy, arthritis, elevated serum IgM levels, or cryoglobulins containing IgM. The duration of cardiac involvement was usually brief (3 days to 6 weeks). The clinical picture in these patients has similarities to acute rheumatic fever; but in Lyme disease, complete heart block may be commoner, myopericardial involvement tends to be milder, and valves seem not to be affected.

Adult↗
PubMed1980

Below knee amputation and rehabilitation of amputees.

Of 373 below knee amputations, the healing rate was 82 per cent, primary healing occurring in 73.3 per cent. A permanent prosthesis was fitted on 283 patients. We attribute this success to the multidisciplinary team approach, the skilled surgical technique, the use of an intraoperative prosthesis and the patients motivation and cooperation.

Adult↗