Biomedical subjects

A S Dontas

Publications and source records attributed to A S Dontas.

At least 19 recordsLinked to original sources

PubMed1992

Short vs. long cotrimoxazole courses in eradicating bacteriuria in the elderly.

To test whether longer duration of treatment of asymptomatic bacteriuria in old age could improve the efficacy of cotrimoxazole therapy, three regimens were given to 75 ambulant bacteriuric residents of a retirement home, aged greater than or equal to 68 years. The groups and regimens were: A:23 subjects (160/800 mg b.i.d. orally x 3 days). B: 24 subjects (160/800 mg i.m. x 10 days); C: 28 subjects (160/800 mg b.i.d. orally x 20 days). One week, one month and five months post-therapy urines were negative in 78.3% vs 52.9% vs 42.9% of group A, in 54.2% vs 56.5% vs 50% of group B and in 57.1% vs 60.7% vs 68% of group C subjects respectively. The data indicate that: 1) the efficacy of any schedule is only moderate irrespective of the presence of antibody-coated bacteria in urine; 2) a 3-day course appears more effective at one week post-therapy; 3) at one and five months greater than or equal to 50% of the subjects were infection-free, the 20 day treatment resulting in fewer failures; 4) subjects with long-term eradication had no mobility problem, low serum creatinine and a normal urinary tract as seen by ultrasound.

Administration, Oral↗

PubMed1992

Are race and sex differences in lung function explained by frame size? The CARDIA Study.

Using the CARDIA cohort of 20- to 32-yr-old black and white men and women, FVC and FEV1 were standardized for standing height, sitting height, leg height, elbow breadth, and biacromial diameter in such a way that the standardized lung function showed minimal statistical dependence on these measures of frame size. Race and sex differences in lung function have been reported even after adjustment for height; however, these differences might depend on aspects of frame size other than height. We found that within this age group height2 provided robust standardization for FVC and FEV1 for all race and sex strata of the population. Height explained approximately 40% of the variance of FVC and FEV1 in whites, 30% in black women, and 20% in black men. In black men only, standardization for the combination of sitting height, leg height, elbow breadth, and biacromial diameter improved explained variance to nearly 40% for FVC and nearly 30% for FEV1. After standardization for height, FVC and FEV1 were found to be 14 to 19% higher in whites than in blacks, and in men than in women. Standardization of FVC and FEV1 for sitting height, leg height, elbow breadth, and biacromial diameter combined reduced these differences to 13-16%. Thus, race and sex differences in lung function exist even after detailed adjustment for frame size.

Adult↗

PubMed1991

Survival in a residential home: an eleven-year longitudinal study.

The length of survival and various risk factors were studied utilizing 408 residents (141 men, 267 women) of a large residential home. The subjects, aged 68 years or more at entry, admitted between 1978 and 1983, were physically independent, continent, and non-diabetic. They were followed until December 31, 1988, by which time 78% had died. The multivariate proportional hazard analysis showed the following entry variables to have the indicated effects on relative mortality rate ratios: 5-years' higher age (+10%, NS), persistent bacteriuria (+13%, NS), abnormal ECG (+26%, NS), current smoking (+63%, P less than 0.01), mildly impaired mobility (+96%, P less than 0.001), higher levels of in-study systolic pressure in 10-mm Hg steps (-4%, NS), higher entry serum cholesterol in 1-mmol/L steps (-7%, NS), and higher hematocrit in 5% steps (-14%, P less than 0.02). Female sex was associated with a +25% (NS) rate ratio; socioeconomic status and body weight were without effect. These data highlight the relative importance of specific factors associated with survival of persons within retirement homes and indicate that: (1) the presence of mild impairment of mobility at entry is by far the strongest predictor of early death; (2) smoking and lower hematocrit also exert important adverse effects; and (3) certain "risk factors", ie elevated systolic blood pressure and serum cholesterol, have a minimal protective effect, if any, in this age group.

Aged↗

PubMed1990

Three-day antibiotic therapy in bacteriuria of old age.

A three day oral antibiotic course was given to 71 elderly bacteriuric subjects with no or only moderate mobility problems. Seven of 17 men (41%) and 34 of 54 women (63%) had strongly positive antibody coated bacteria (ACB) in the urine. Following sensitivity tests and randomization one of the following agents was given: cefadroxil 1 g tid (13 subjects): co-trimoxazole 160/800 mg bd (23 subjects); or norfloxacin 400 mg bd (35 subjects). One week after therapy urines were negative in 13 men (76.5%) and 37 women (68.5%). Patients who were fully mobile and/or were ACB(-) responded better than those with moderate mobility problems or who were ACB(+). At six months, urines were negative in six (40%) of 15 men and 15 (33.3%) of 45 women. Two men and six women of these 21 subjects had a positive urine at one month. Of the three agents tested cefadroxil was less effective in women. The study indicates that a three day course will clear bacteriuria in about 70% of patients at one week, but only about 25% will remain free of infection at six months; these are usually patients with adequate mobility and normal renal function.

Aged↗

PubMed1990

Soluble interleukin-2 receptors and autoantibodies in the serum of healthy elderly individuals.

Recently, we reported an increased incidence of various autoantibodies in a healthy elderly population (Group A, 64 subjects). Presently we examined whether there is variability in the expression of the age-associated immunological aberrations between different geriatric populations by extending our observations in another healthy elderly population (Group B, 119 subjects). We also determined the serum levels of soluble IL-2 receptors (sIL-2R) attempting to define the activation status of the immune system during senescence. Compared to non-elderly controls, healthy elderly individuals exhibited a significantly higher incidence of autoantibodies as well as significantly higher levels of sIL-2R in serum (p less than 0.001), the latter possibly suggesting the occurrence of lymphocytic activation during the ageing process. The overall prevalence of autoantibodies was statistically associated with the presence of raised sIL-2R levels in serum (p less than 0.005). These aberrant immunological phenomena were more frequent among the elderly of group A, compared to group B (p less than 0.005). In contrast to the uniform expression of various autoantibodies previously observed in group A, the autoantibody profile of group B consisted mainly of rheumatoid factor and antibodies to single-stranded DNA. Finally, no association could be demonstrated between the presence of autoantibodies and HLA antigens in 42 elderly studied.

Aged↗

PubMed1987

Diuresis bacteriuria in physically dependent elderly women.

Among 34 women aged 74-96 years, residents of a Home for the Aged, with reduced mobility and repeatedly negative urine cultures, 16 (47%) responded to a rapid hydration and 20 mg frusemide administered intravenously with a transient bacterial excretion usually trailing the diuresis. Antibody-coated bacteria were detected in 11 of the 13 Gram-negative isolates tested. Women with urine turning positive had significantly lower glomerular filtration rates and more advanced renal tubular defects than the steadily nonbacteriuric subjects of the same age. Progress to renal insufficiency was somewhat faster and all-causes mortality at 1 year was higher in subjects with urine turning positive. Diuresis bacteriuria originating from the upper urinary tract along with frank bacteriuria may be detected in up to 70% of women in their mid-80s and represents a likely source of the most common infection in man's last period of life.

Activities of Daily Living↗

PubMed1986

The diet and 15-year death rate in the seven countries study.

In 15 cohorts of the Seven Countries Study, comprising 11,579 men aged 40-59 years and "healthy" at entry, 2,288 died in 15 years. Death rates differed among cohorts. Differences in mean age, blood pressure, serum cholesterol, and smoking habits "explained" 46% of variance in death rate from all causes, 80% from coronary heart disease, 35% from cancer, and 45% from stroke. Death rate differences were unrelated to cohort differences in mean relative body weight, fatness, and physical activity. The cohorts differed in average diets. Death rates were related positively to average percentage of dietary energy from saturated fatty acids, negatively to dietary energy percentage from monounsaturated fatty acids, and were unrelated to dietary energy percentage from polyunsaturated fatty acids, proteins, carbohydrates, and alcohol. All death rates were negatively related to the ratio of monounsaturated to saturated fatty acids. Inclusion of that ratio with age, blood pressure, serum cholesterol, and smoking habits as independent variables accounted for 85% of variance in rates of deaths from all causes, 96% coronary heart disease, 55% cancer, and 66% stroke. Oleic acid accounted for almost all differences in monounsaturates among cohorts. All-cause and coronary heart disease death rates were low in cohorts with olive oil as the main fat. Causal relationships are not claimed but consideration of characteristics of populations as well as of individuals within populations is urged in evaluating risks.

Adult↗

PubMed1985

Serum cholesterol and cancer mortality in the Seven Countries Study.

In the Seven Countries Study, carried out in Finland, Greece, Italy, Japan, The Netherlands, the United States, and Yugoslavia, among 11,325 "healthy" men aged 40-59 years in 15 years, there were 594 cancer deaths. Among 477 cancer deaths five years after cholesterol measurement, there was a significant excess of lung cancer deaths in the bottom 20% of the cholesterol distributions in the populations. Age, blood pressure, smoking habits, occupation, and relative body weight did not help explain this. A U-shaped relationship between cancer and cholesterol was not seen in any population. Trend analysis with various cutting points indicated increasing risk of lung cancer death at cholesterol levels under 170 mg/dl. The 45 men dead from cancer in the first two years had lower cholesterol levels than their compatriots who died from cancer later but they did not differ in relative weight or fatness. In contrast to relationships for individuals within populations, the highest cancer death rates were in northern Europe, where the general level of cholesterol was also highest. Other characteristics of the populations--age, relative weight, smoking habits, blood pressure, physical activity, and vitamin A and ascorbic acid in the diet--did not help in the attempt to understand the regional differences in cancer mortality. There is no evidence that any of the observed cancer-serum cholesterol relationships among or within the populations involve an effect of serum cholesterol concentration on oncogenesis or cancer mortality but the possibility of such an effect cannot be denied.

Adult↗

PubMed1979

Prospective comparative evaluation of gentamicin or gentamicin plus cephalothin in the production of nephrotoxicity in man.

Recent studies in animal models have demonstrated that in contrast with humans, cephalothin (CTIN) does not increase gentamicin (GENT) nephrotoxicity, but rather protects against it, particularly when CTIN is given simultaneously with GENT. To investigate this phenomenon in humans a study was designed in which 67 patients suffering from mild infections were investigated. Thirty-three of them served as the control group receiving GENT alone at a dose of 1.5 mg/kg/8 hourly, while the remaining 34 received CTIN at a dose of 2 g or 3 g 8 hourly by i.v. bolus, either simultaneously with GENT or separated by a 4-h interval. Findings showed that: (a) cylindruria developed in 66.6% and 82.3% and 82.3% in the GENT and GENT + CTIN groups respectively, (b) urinary beta-glycuronidase activity increased in 57.5% and 75% (c) serum creatinine exceeded by 0.3 mg the initial values in 21.2% and 27.6% and (d) the blood urea was above 50 mg% in 18.1% and 17.6% of the patients. These results indicate that: (a) regardless of the route and order of administration simultaneous treatment did not protect against nephrotoxicity in humans; (b) the combination of GENTA plus CTIN has no synergistic effect on the production of elevated serum creatinine and rising blood urea; (c) urinary beta-glycuronidase is not a significant predictor of eventual nephrotoxicity; (d) the following risk factors influenced the appearance of nephrotoxicity in both groups: (1) elevated GENT trough levels greater than or equal to 2 mg/l; (2) a course of treatment longer than 10 days.

Adult↗

PubMed1976

Significance of diuresis-provoked bacteriuria.

Of 52 clinically healthy, ambulant elderly subjects with urine that was sterile or contained less than 0.2 X 10(5) bacteria/ml before diureisi, 11 (21.2%) responded to oral water loading and intravenous treatment with furosemide with a bacterial excretion rate of greater than 2.4 X 10(5)/min. Subjects with bacteriuria had decreased blood pressure, rate of creatinine clearance, maximal level of urinary creatinine, and maximal urinary flow. Twenty-nine of the nonbacteriuric and eight of the subjects who developed bacteriuria after diuresis were retested one to two years later. No subject had received antibacterial agents in the interim. The infections of four of the original subjects who had developed bacteriuria had cleared up and showed functional improvement. The remaining four subjects who had developed bacteriuria during the first study and three subjects who had been nonbacteriuric during the first study had concentrations of bacteria ranging from 0.05 X 10(5) to 1.80 X 10(5)/ml before diuresis in the second study, and excreted increasing numbers of bacteria (from 0.12 X 10(5) to 9.0 X 10(5)/min) in response to the diuretic loading. Two of the subjects who were bacteriuric in both surveys were infected with different bacteria during the two studies. The data show the high frequency of occult bacteriuria in ostensibly healthy elderly patients that is revealed only by forced diuresis, the detectable functional deficits, the improvement after clearing of the infections, and the rapid turnover between infected and clear periods.

Aged↗

PubMed1975

Tumor-like pulmonary manifestations of congestive heart failure.

Two cases of "phantom tumors" of the right lung on elderly subjects with congestive heart failure are described. One presented a picture of patchy bronchopneumonia, whereas the second had been diagnosed as a lung carcinoma 1 month before hospitalization because of a round lesion. In both cases the radiological picture cleared up within a few days following rest, diuresis and digitalization. The possibility of congestive heart failure as a cause for development of circumscribed pulmonary opacities should always be kept in mind.

Aged↗

PubMed1974