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T Borkowski

Publications and source records attributed to T Borkowski.

At least 19 recordsLinked to original sources

Perceptions of the benefits and costs associated with condom use and unprotected sex among late adolescent college students.

To assess the differential effects of the perceived benefits and costs associated with both condom use and unprotected sex on sexual risk behaviors, data were collected from 704 ethnically diverse male and female sexually experienced late adolescent college students (aged 17-25). Perceived benefits and costs for condom use and perceived benefits and costs for unprotected sex were measured separately through an anonymous self-report survey. In addition, participants completed measures of self-efficacy for practicing safer sex and temptation for unsafe sex in various situations, and three measures of sexual risk-taking (stage of change for condom use, consistency of condom use during the past month, and whether or not a condom was used for the last act of intercourse). Univariate analyses indicated that benefits and costs of condom use, benefits of unprotected sex, self-efficacy and situational temptation were all related to sexual risk-taking. Gender differences were identified, with females reporting more benefits of condom use and costs of unprotected sex, fewer benefits of unprotected sex and costs of condom use, greater self-efficacy for practicing safer sex, and less situational temptation for unsafe sex. Multivariate analyses indicated that sexual risk behaviors were most related to situational temptation, self-efficacy for safer sex, and perceived benefits of unprotected sex. The results suggest that, among late adolescents, perceived benefits of the unhealthy behavior (unprotected sex) were better determinants of sexual risk-taking than were perceived benefits (or costs) associated with the healthy behavior (condom use). Perceived costs associated with unprotected sex were unrelated to sexual behaviors. These findings support previous work identifying adolescents as more driven by their perceptions of the positive benefits associated with risky behaviors, rather than knowledge of the costs or dangers involved in risk-taking.

Acquired Immunodeficiency Syndrome↗

Outcome predictors of high-energy transurethral microwave thermotherapy.

PURPOSE: Despite the good results of high-energy transurethral microwave thermotherapy (TUMT) for treatment of benign prostatic hyperplasia (BPH), it still is difficult to predict the response to treatment on an individual basis. In addition to clinical baseline parameters, histologic parameters seem to play a role in response variance after TUMT. High-energy TUMT has become widely accepted as a minimally invasive outpatient treatment in patients with lower urinary tract symptoms and BPH. Most patients benefit substantially from targeted microwave thermotherapy; however, little is known about optimal patient selection and the most relevant outcome parameters. MATERIALS AND METHODS: We evaluated Medline-based studies published between 1989 and 2000, including 900 patients suffering from lower urinary tract symptoms due to BPH who were undergoing TUMT. We evaluated outcome predictors for TUMT, such as histopathological parameters, prostate-specific antigen, and volume. RESULTS: Histologic and clinical outcome parameters were identified. Patient-to-patient differences in stromal-to-epithelial ratio of prostate tissue did affect outcomes. Poor responders to TUMT seemed to have a higher vessel density and a lower epithelial/stromal ratio. Relatively more abundant epithelial cells in the prostate tissue may lead to more favorable outcomes. Use of higher energy, patients with higher grade of obstruction, younger patient age, larger prostate volume (>25 mL), and higher prostate-specific antigen levels seemed to be associated with a better response to TUMT. CONCLUSIONS: New energy protocols could help tailor treatment to the individual needs of each patient. Nomograms based on volume, age, and pressure-flow parameters could assist in making clinical recommendations and identifying treatment responders; however, the total amount of energy appeared to have a high impact on the prediction of response.

Humans↗

Mitochondrial tRNA in hyperthyroidism.

The mitochondrial tRNA were prepared from liver and brain tissues of thyroxinized and control rabbits. The presence of tRNA for twenty amino acids both in liver and brain mitochondria was revealed. The quantity of radioactive amino acids bound to the mitochondrial tRNA was higher in hyperthyreosis than in control animals but considerable differences between the brain and liver tissues were observed.

Animals↗

Activity of aminoacyl-tRNA synthetases in experimental hyperthyroidism in muscle tissues of the rabbit.

In cardial and femoral muscles of rabbits specific activities of aminoacyl-tRNA synthetases for twenty amino acids were generally similar, namely the activities towards amino acids and their amides, leucine, isoleucine, histidine, tyrosine, proline and serine were considerably lower than towards the remaining amino acids. Specific activities of most aminoacyl-tRNA synthetases were higher in hyperthyroidism than in euthyreosis, and were higher in femoral muscle than in heart. The response to thyroxine treatment of individual aminoacyl-tRNA synthetases in both kinds of muscles varied with respect to most of the amino acids.

Amino Acyl-tRNA Synthetases↗

Heavy and light forms of some aminoacyl-tRNA synthetases in fraction X, microsomes and cytosol of rabbit liver.

Aminoacyl-tRNA synthetase activity for alanine, glutamic acid, lysine and phenylalanine was studied in the three subcellular fractions of rabbit liver: fraction X, microsomes and cytosol. From 60 to 80% of the enzyme activities were found in fraction X and microsomes. Fraction X was especially rich in the synthetase activities. By means of gel chromatography, heavy (over 10(6) daltons) and light (below 480 X 10(3) daltons) forms of lysyl- and phenylalanyl- but only light ones of alanyl- and glutamyl-tRNA synthetase activities were found in all the subcellular fractions studied. It is concluded that in higher organisms (mammals) all aminoacyl-tRNA synthetases, at least in part, are associated with cell structural constituents.

Amino Acyl-tRNA Synthetases↗

Isolation from calf brain of a polypeptide fraction affecting aminoacylation of tRNA.

The preparation of tRNA obtained from calf brain by three conventional methods exhibits the presence of a slow-migrating fraction in polyacrylamide-gel electrophoresis. This fraction constitutes 2-2.5% of the isolated tRNA and has been identified as a polypeptide of molecular weight of 6000. The aminoacylation with glutamic acid, glycine, leucine and phenylalanine of tRNA devoid of this polypeptide is reduced by half as compared with the initial preparation.

Amino Acyl-tRNA Synthetases↗