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Biomedical subjects

J C Barbosa

Publications and source records attributed to J C Barbosa.

9 recordsLinked to original sources
PubMed1998

Statistical methodology: VII. Q-methodology, a structural analytic approach to medical subjectivity.

Q-methodology is a relatively unknown tool to medical researchers, that uses a mixed quantitative/qualitative statistical technique known as by-person factor analysis to study subjectivity. Q-methodology allows the grouping of individuals according to their subjective feelings about a topic, without requiring preconceived ideas regarding the structure of those subjective feelings. Q-methodology is demonstrated using a study in which attitudes of emergency medicine residents toward computer education are explored systematically and classified in terms of statistically distinct factor viewpoints. In this example, Q-methodology identifies 4 attitude groups, as related to computers and computer education: 1) interested, eager to learn; 2) frustrated and interested, but with reservations; 3) interested mainly in benefits, willing to expend minimal effort; and 4) knowledgeable, independent learner. Q-methodology can be used to determine the structure of attitudes on a subjective topic, often yielding new insights.

Attitude↗
PubMed1997

Haematological and biochemical alterations in leprosy patients already treated with dapsone and MDT.

Dapsone (DDS) is useful in the treatment of a number of inflammatory conditions which are characterized by neutrophil infiltration. It is the drug of choice for the treatment of leprosy and prophylaxis of malaria. Haematological side effects of methaemoglobinaemia and haemolysis have been long recognized. However, the frequency and severity of these side effects in patients already treated with DDS as a single drug or as part of a multidrug therapy (MDT) have not been well documented. We report herein an investigation of the effect of dapsone long-term treatment on the haematological and biochemical alterations in leprosy patients undergoing dapsone as a single drug (DDS group) or as part of a multidrug therapy in combination with rifampin and clofazimine (MDT group). Methaemoglobinaemia and haemolytic anaemia were the principal side effects observed. Reticulocytes were found to be elevated (> 1.5%) in 90% of the patients. Heinz bodies were also detected (6.6% of the patients). The osmotic fragility test showed a reduction in cell resistance and in the evaluation of white cells a severe eosinophilia was found. Hepatic, pancreatic and renal evaluation by the determination of biochemical parameters showed rare and occasional changes of no apparent clinical significance. We conclude that haematological side effects of dapsone are significant even at doses currently used to treat leprosy (100 mg/day) and that rifampin and clofazimine do not increase the incidence of these effects during long-term treatment.

Clofazimine↗
PubMed1993

Heart muscle cells acutely infected with Trypanosoma cruzi: characterization of electrophysiology and neurotransmitter responses.

Primary cell cultures of mouse ventricular myocardium were infected with Trypanosoma cruzi, to study the consequences of T. cruzi-muscle cell interaction on the rate of spontaneous contractions, on the responses to norepinephrine, and on action potential parameters. Single cells or small cell groups of infected cultures were subjected to pharmacological and electrophysiological experiments. In concentrations ranging from 1 nM to 100 microM, norepinephrine exerted positive or negative chronotropic effects mediated by alpha-adrenergic receptors. A significant number of infected cells (25%) did not respond to the agonist. Two days after infection the cultures exhibited a higher frequency of spontaneous contractions (20%), paralleled by an increase in firing rate and a decrease in the action potential duration without significant changes in maximum diastolic potential and action potential amplitude. A decrease in alpha-adrenergic receptor-mediated positive chronotropic response to norepinephrine was also observed in 2-day infected cells. Cells made to phagocyte ferritin particles showed an increase in the rate of spontaneous contractions, but no changes in the positive chronotropic responses to norepinephrine. In conclusion, these observations show that during acute infection with T. cruzi, there are alterations in automaticity and in the chronotropic responses to norepinephrine, whose mechanisms are related to the process of parasite endocytosis by the cardiac cells.

Animals↗
PubMed1990

The relationship among adiposity, diet, and hormone concentrations in vegetarian and nonvegetarian postmenopausal women.

The relationships among anthropometric variables, dietary nutrients, and plasma steroid, polypeptide, and binding-protein hormone concentrations were investigated in 24 Seventh-day Adventist postmenopausal women, 12 vegetarian (SV) and 12 nonvegetarian (SNV). Fasting blood and 7-d dietary intake information were collected. SVs consumed significantly more crude and dietary fiber and fewer saturated fatty acids than did SNVs. The thigh and sum of three skinfold-thickness measurements were significantly greater for SNVs than for SVs. Plasma concentrations of estradiol-17 beta were significantly lower in SVs than in SNVs. Significant relationships were observed for the combined groups (SV and SNV) between estradiol-17 beta and triceps and suprailiac skinfold thickness and body fat. Plasma concentrations of estradiol-17 beta of the combined groups revealed a significant negative relationship between their crude and dietary fiber intakes. Further study delineating the effects of adiposity and dietary nutrients on basal concentrations of sex hormones is warranted.

Adipose Tissue↗
PubMed1989

Hematological, anthropometric, and metabolic comparisons between vegetarian and nonvegetarian elderly women.

The purpose of this study was to investigate hematological, anthropometric, and metabolic differences in elderly women who were similar in most respects except for choice of diet. Nineteen vegetarian (V) and 12 non-vegetarian (NV) elderly women (mean ages 72.3 +/- 1.4 and 69.5 +/- 1.0 years, respectively) were recruited based on several selection criteria including race, religion, education, Quetelet Index, absence of major chronic disease and use of medications, physical activity, and geographic area. Average years of adherence by V and NV groups to dietary regimens were 46.3 +/- 3.3 and 69.6 +/- 1.0, respectively; Hematological comparisons revealed that the V elderly women had significantly lower glucose (4.60 +/- 0.09 vs 5.13 +/- 0.11 mmol/L), low-density lipoprotein cholesterol (3.14 +/- 0.19 vs 4.09 +/- 0.27 mmol/L) and total cholesterol levels (5.41 +/- 0.20 vs 6.48 +/- 0.29 mmol/L) than the NV elderly women (P less than 0.01) for each. The V elderly women tended to have less body fat and midupper arm muscle area than the NV. No differences between groups were found in a variety of metabolic and electrocardiographic parameters during graded maximal treadmill testing except for lower heart rates in the V women. VO2max was not significantly different between the V and NV elderly women (23.8 +/- 1.5 vs 21.9 +/- 0.8 ml.kg-1.min-1, respectively). In summary, when healthy elderly V women are compared with closely matched NV peers, the vegetarian diet is associated with several benefits, primarily lower blood glucose and lipid levels, but not greater functional capacity.

Aged↗
PubMed1989

Dietary status of Seventh-Day Adventist vegetarian and non-vegetarian elderly women.

The purpose of this study was to investigate nutrient intakes of Seventh-Day Adventist elderly women who were similar in many demographic and life-style factors except for choice of diet. Twenty-three vegetarian and 14 non-vegetarian elderly women (mean +/- standard error ages 72.2 +/- 1.3 and 71.1 +/- 1.4 years, respectively) were recruited on the basis of several selection criteria, including race, religion, education, geographic area, Quetelet index, self-reported absence of major chronic disease and use of medications, and physical activity. Average years +/- SE of adherence to dietary regimens were 47.0 +/- 2.9 and 71.2 +/- 1.4 in the vegetarian and non-vegetarian groups, respectively. Results from analysis of 7-day food records showed that vegetarians consumed significantly less cholesterol, saturated fatty acids, and caffeine but more carbohydrate, dietary fiber, magnesium, vitamins E and A, thiamin, pantothenic acid, copper, and manganese than non-vegetarians (p less than .05). On the basis of group means, 67% of the Recommended Dietary Allowance was met for all nutrients except zinc and vitamin D in both groups, and vitamins B-6, folacin, and vitamin E in the non-vegetarians. Compared with non-vegetarians, vegetarians had significantly lower serum glucose (5.18 +/- 0.11 vs. 4.65 +/- 0.09 mmol/L), low-density-lipoprotein cholesterol (4.08 +/- 0.25 vs. 3.34 +/- 0.19 mmol/L), and total cholesterol levels (6.46 +/- 0.27 vs. 5.62 +/- 0.21 mmol/L) (p less than .05). In summary, when healthy elderly vegetarian women were compared with closely matched non-vegetarian peers, the vegetarian diet was associated with improved nutrient intake and associated reductions in blood glucose and lipid levels.

Aged↗
PubMedDate not supplied

[The meaning of living with chronic renal failure].

This study is part integrant of result of my inquietude in relationship to the ill person with renal chronic illness, subject of my dissertation. For that, I used qualitative research phenomenological modality, that allowed me to understand the ill and to answer my interrogation: What is to be a renal chronically ill person? The analysis of descriptions revealed the look of the renal chronically ill in relationship with the disease, treatment and the possibility of cure. However in this study I emphasize the meaning to live with chronic renal failure.

Humans↗