Biomedical subjects

T J Prihoda

Publications and source records attributed to T J Prihoda.

At least 37 records · Page 2Linked to original sources

PubMed1995

Characteristics of childhood sexual abuse in a predominantly Mexican-American population.

Little has been written about the characteristics of childhood sexual abuse among Mexican Americans. In addition, certain aspects of the epidemiology of reported sexual abuse in the United States have changed significantly over the past 12 years. To better understand how characteristics of sexual abuse vary with ethnicity, race, gender, and age, we reviewed the records of 2,130 children under age 18 who were evaluated at our university-based facilities for possible sexual abuse from 1987 to 1989. The demographic, historical, and physical findings of the cases from our predominantly Mexican-American population were analyzed. T-test, analysis of variance, and chi-square analyses were used to test for differences related to ethnicity, race, gender, and age. Significant differences in these factors were found with respect to the relationship of the perpetrator to the child, the number of perpetrators, the interval from the abuse to the evaluation, the types of abuse, and the findings of the physical examination. This study demonstrates the important influences of ethnicity, race, gender, and age on characteristics of childhood sexual abuse. Awareness of these influences can be helpful in understanding factors that contribute to childhood sexual abuse, preparing for legal proceedings, and designing appropriate prevention programs.

Adolescent↗

PubMed1995

Regional comparisons of child abuse and related variables in the United States.

The objective of this article is to familiarize the health care professional with 1990 national data on child abuse and to review some of the trends reported in the literature. The United States was divided into Northeast, Midwest, South, and West. Data were collected, analyzed, and transformed to calculate the incidence and types of abuse reported by region. Variables of interest were income, marital status, perpetrator, age of victim, and drug use by region. To determine significant differences among regions for each type of abuse and related variable, frequency distributions were calculated and chi-squared tests were used. State data summaries were measured for correlation analysis. The West was highest in reported incidence of child abuse (5.9%) and, specifically, physical abuse (36.7%). California reported 55% of the physical abuse in the West. In all regions, neglect and physical maltreatment were reported more than sexual and emotional abuse. The incidence of neglect in the south (52.8%) was greater than in any other region and did not correlate to income in this region. Early detection of child abuse can aid in preventing fatalities. This information should increase awareness of child abuse and result in an increase in reporting if abuse is suspected.

Adolescent↗

PubMed1995

Salivary PAF levels correlate with the severity of periodontal inflammation.

Platelet-activating factor (PAF), a potent phospholipid mediator of inflammation, has been previously identified in inflamed gingival tissues and gingival crevicular fluid. However, the role of PAF in oral pathobiology remains unknown. The purpose of the present study was to evaluate the relationship between salivary PAF levels and the severity of periodontal inflammation. PAF activity in lipid extracts of whole (mixed) saliva collected from 69 untreated subjects immediately prior to routine oral evaluation was determined by platelet bioassay. Significant positive correlations were observed between the level of PAF in saliva and measures of periodontal inflammation, i.e., the percentage of periodontal probing depths greater than 4 mm, the number of periodontal bleeding sites, and the number of histologically identified polymorphonuclear neutrophilic leukocytes (PMN) in saliva. Moreover, when subjects were subdivided into groups on the basis of periodontal probing depths, a significant correlation was observed between salivary PAF levels and the extent of periodontal disease, i.e., PAF levels in saliva progressively increased from the healthiest group to the most severely affected group. Thus, salivary PAF levels correlate with the severity of periodontal inflammation. These results support the hypothesis that this pro-inflammatory phospholipid autacoid may participate in the pathogenesis of periodontal tissue injury and disease.

Adolescent↗

PubMed1995

The effect of initial periodontal therapy on salivary platelet-activating factor levels in chronic adult periodontitis.

Platelet-activating factor (PAF), a potent phospholipid inflammatory mediator, is increased in the mixed saliva of subjects with periodontal disease and correlates with the extent of oral inflammation. The present study was designed to provide a longitudinal evaluation of the effect of initial periodontal therapy (home care instruction, prophylaxis, and scaling/root planing) on salivary PAF levels in chronic adult periodontitis patients (n = 15). Mixed saliva was collected prior to, during, and after initial therapy and was utilized to assess PAF levels after lipid extraction and fractionation as well as to histologically assess the number of polymorphonuclear leukocytes (PMN). PAF activity was determined in bioassay relative to authentic PAF (1-O-hexadecyl-2-acetyl-sn-glycero-3-phosphocholine; 16:0-alkyl-PAF). Initial salivary PAF levels (12.1 +/- 2.8 pmole equivalents of 16:0-alkyl-PAF/ml saliva; mean +/- SE) decreased following supragingival plaque control (9.6 +/- 2.4) and were further reduced following scaling and root planing (5.7 +/- 1.4). In parallel, salivary PMN levels were significantly reduced and clinical estimates of periodontal disease were significantly improved; i.e., there was a decrease in the percentage of sites with both bleeding on probing (from 46.1 +/- 4.6% of sites at pretreatment to 25.9 +/- 2.6% after scaling and root planing) and probing depths > or = 4 mm (from 16.7 +/- 1.9% of sites to 10.3 +/- 1.2%). Thus, initial periodontal therapy reduced salivary PAF levels in concert with improvements in clinical estimates of marginal and submarginal periodontal inflammation suggesting that PAF may participate in inflammatory events during periodontal tissue injury and disease.

Adult↗

PubMed1994

Illicit drug injectors in three Texas cities.

In three Texas cities illicit drug injectors not in treatment were located by outreach and interviewed with a standard questionnaire. In all the cities the drug injectors were predominantly undereducated and unemployed young men from minority groups. In Dallas and Houston most were Black, while in San Antonio most were Hispanic. The most frequently reported primary drug in Houston was cocaine, but in Dallas and San Antonio it was heroin. The high needle risk for AIDS and the low rates of positive HIV antibody tests in these samples present a special window of opportunity for prevention of AIDS.

Acquired Immunodeficiency Syndrome↗

PubMed1993

Digital subtraction temporomandibular joint tomography.

Receiver operating characteristics analysis was performed to demonstrate differences in diagnostic performance among conventional tomograms, digitized tomograms, and subtraction tomograms. Digital subtraction tomography was found to be the best imaging modality for detecting artificially created lesions in the two selected temporomandibular joint locations. There was a statistically significant difference in diagnostic performance between conventional tomograms and subtraction tomograms for the detection of temporomandibular joint bony lesions. There was also a statistically significant difference in diagnostic performance between digitized tomograms and subtraction tomograms in the detection of these bony lesions. There was no statistically significant difference in diagnostic performance between conventional tomograms and digitized tomograms for the detection of temporomandibular joint bony lesions. The significance level was set at p = 0.05. Results of the analyses of variance showed that with digital subtraction tomograms, observer reliabilities were higher than with conventional and digitized tomograms.

Evaluation Studies as Topic↗

PubMed1993

Hispanic children with asthma: morbidity.

Hispanic children represent a large and growing segment of the poor and disadvantaged children in our country. Asthma and other chronic respiratory diseases have a significant impact on poor children. Yet there are few descriptions of the specific morbidities and barriers to health that Hispanic children with asthma encounter, and data on predictors of morbidity among these children are unavailable. The purpose of this study is to describe the morbidity associated with asthma in Hispanic children and to identify factors that predict morbidity. A group of Hispanic children with moderate asthma followed in the clinics of the University of Texas Health Science Center at San Antonio were studied. Children aged 6 to 16 years with at least two acute-care visits or one hospitalization for asthma during the previous year were enrolled. Data sources included standardized questionnaires, spirometry, medical records, and school attendance records. Seventy-eight Hispanic children were enrolled in the study (mean age = 9.4 +/- 2.7 [SD]; 62% male). Fifty-two (67%) of children had been hospitalized previously. The other morbidity variables (mean +/- SD) were number of days/week impaired (1.1 +/- 1.2), number of days absent from school per year (13 +/- 9.6), number of acute-care visits per year (3.3 +/- 2.4), and number of hospital admissions per year (0.6 +/- 0.8). The mean forced expiratory volume in 1 second/forced vital capacity was 79.3% (+/- 9.1) and the mean forced expiratory flow, mid-expiratory phase, percent predicted was 69.9% (+/- 25.1). Thirty-four children (44%) were exposed to cigarette smoke in the home.(ABSTRACT TRUNCATED AT 250 WORDS)

Absenteeism↗

PubMed1992

The application of generalizability theory to surface electromyographic measurements during psychophysiological stress testing: how many measurements are needed?

Generalizability theory is an extension of classical reliability theory that allows multiple sources of measurement error in an experimental design to be investigated simultaneously. In the present study, generalizability theory was used to evaluate measurement error in psychophysiological test procedures used to differentiate tension headache patients from normal controls based upon measures of electromyographic (EMG) responding. Thirty-three subjects who met diagnostic criteria for tension-type headache and 40 normal control subjects who rarely or never experienced headache participated in two laboratory sessions. EMG activity of head and neck muscles was recorded while subjects performed baseline, relaxation, choice reaction time, psychomotor tracking, and cold pressor tasks. Variance components were computed for an experimental design having subjects nested within experimenters and crossed with sessions and replications. Generalizability coefficients were computed for combinations of various numbers of sessions and replications. The generalizability of EMG measures was highly variable, depending on the experimental conditions in force. The largest sources of measurement error were attributed to the unique responsiveness of individual subjects under a particular set of treatment conditions. For some stress tests currently in use, data from several testing sessions may need to be averaged in order to achieve acceptable levels of generalizability. Generalizability greater than 0.80 can be expected only rarely when data are collected during a single session. In the research setting, low generalizability may account for the failure of EMG-based stress tests to differentiate tension headache patients from controls during stressful task performance. In the clinical setting, the generalizability of information derived from "stress profiling" or muscle "scanning" techniques, which depend on results obtained during a single testing session, is doubtful.

Adult↗

PubMed1992

The effect of influential outliers on parameter estimation in regression analysis.

A comment is made on an article recently published in this journal by Borgeat, Elie, and Castonguay (1991). It is noted that the raw data contained an outlier which is shown to have had a large influence on their estimation of the regression coefficient. Analysis of the data using a nonparametric statistic that is optimal for long-tailed distributions showed that the true regression coefficient is probably smaller than that reported. Other approaches to the analysis of data containing influential outliers are discussed.

Biofeedback, Psychology↗

PubMed1992

The effects of pH and osmolality on bacterial growth in amniotic fluid in a laboratory model.

In studying the effects of amniotic fluid on bacterial growth in a laboratory model, we noted that the pH of the fluid appeared to exert an independent effect. This study was designed to test the ability to control the growth of Escherichia coli in amniotic fluid simply by controlling two important growth conditions, pH and osmolality. The effects of pH and osmolality on growth of E. coli were systematically studied in a standard media and in amniotic fluid. Optimal ranges in standard media were pH of 5.6 to 6.6 and osmolality of 150 to 215 mOsm. When the results of growth at 24 hours were corrected for pH by analysis of covariance, the presence of amniotic fluid or phosphate had no effect. We found pH to be the only variable predictive of bacterial growth in amniotic fluid in this laboratory model.

Amniotic Fluid↗

PubMed1992

Compatibility of Type IV dental stone with polysulfide impression materials.

PURPOSE: In the American National Standards Institute/American Dental Association specification no. 19, compatibility of impression materials with dental stones is assessed by the presence of a 20-microns-wide line reproduced on an unmodified calcium sulfate dihydrate cast. In actual dental practice, modified type IV dental stones are used, although little is known of their compatibility with polysulfide impression materials. This study evaluated the compatibility of 6 polysulfide impression materials and 11 modified type IV dental stones. MATERIALS AND METHODS: A line 20 microns wide was etched on four glass dies. Four samples of each combination of impression material and dental stone were prepared according to the manufacturer's directions with an additional 3 minutes for the final setting time. Compatibility was determined by the presence of the reproduced line on the dental stones, as observed under low angle 10 x magnification by four rater groups. RESULTS: The line was reproduced on all of the impression specimens, and the examiners recorded 66 positive identifications of the line on the stone casts out of a possible 1,056 ratings for a total of 6.25% of the specimens. Out of a possible 66 impression-stone combinations, only 18 reproduced the 20-microns line. The combinations reproducing the lines most frequently (75%) were Neoplex with Blue Die Stone (Columbus Dental, St Louis, MO) and Coeflex with Indic Die Stone (Coe Lab Inc, Chicago, IL). CONCLUSIONS: The study showed that many combinations of polysulfide impression materials and modified type IV dental stones did not reproduce the 20-microns line; therefore, not every polysulfide is compatible with every type IV dental stone.

Calcium Sulfate↗

PubMed1992

The reporting of statistical inferences in selected prosthodontic journals.

Dental periodicals are the fundamental source of prosthodontic research. The ability to understand and contribute to dental literature is basic to the prosthodontic profession. The purpose of this study is to tally relative frequency with which various descriptive (n = 18), graphical (n = 7), and inferential statistical procedures (n = 68) are used in the prosthodontic literature. Our method consists of four procedures: journal selection, choice of 1987 through 1988 articles with inferential statistical content, tally of the statistical procedures in those articles, and quality control procedures used in obtaining these data. At least 50% of 10 prosthodontists selected 17 of 100 journals most likely to be read by prosthodontists. In the 17 journals, 1,320 articles were screened of which 406 were selected and evaluated for their statistical procedures. The bar and line plots were the most common graphical procedures occurring in over one fourth of the 406 articles. Percentages, means, and standard deviations occurred in more than 40%. Although 58% used the .05 significance level, only 0.3% mentioned power. Analysis of variance was used more often than the t tests (42% v 29%), whereas correlation/regression (21%) and chi-square tests (14%) were used less often. The t tests, analysis of variance (Duncan, Tukey, and Student-Newman-Keuls multiple comparison procedures), chi-square tests, correlation and regression, and the Wilcoxon tests occurred in at least 5% of the 406 articles.

Analysis of Variance↗

PubMed1991

The bleeding time effects of a single dose of aspirin in subjects receiving omega-3 fatty acid dietary supplementation.

Dietary supplementation with omega-3 fatty acids reduces platelet aggregation in subjects who usually eat a diet low in these fatty acids. Aspirin also has an antiplatelet effect. The clinical effects of the concomitant administration of these agents were examined in this double-blind controlled crossover trial. Twelve healthy adults were randomized to supplement their diet for 21 days with 8 g of omega-3 fatty acids or identical-looking olive oil capsules. At the end of each treatment period, bleeding times were obtained before and after the administration of one 325-mg aspirin tablet. Overall, percent change in bleeding time after omega-3 fatty acid supplementation was significantly prolonged compared with olive oil supplementation before aspirin administration but not after. Bleeding times were influenced significantly by the order of randomization in the two treatment groups. Changes in post-aspirin bleeding time varied in subjects after they received olive oil. Post-aspirin bleeding times after omega-3 fatty acid supplementation were prolonged compared with baseline values but not significantly prolonged when compared with those after olive oil administration. The authors concluded that the concomitant administration of a single dose of aspirin does not prolong bleeding time in subjects who eat a diet enriched by omega-3 fatty acids versus a diet enriched by olive oil.

Aspirin↗

PubMed1991

Variations in adult cortical bone mass as measured by a panoramic mandibular index.

This study defines a new radiomorphometric index of mandibular cortical bone mass, the panoramic mandibular index (PMI). Differences in the index in a population of 353 adult subjects, equally divided by sex, age (30 through 79 years), and racial group (black, Hispanic, white), were evaluated. The data were analyzed with respect to side, racial group, sex, age, and combinations of these variables. Blacks were found to have a greater mean PMI than Hispanics or whites, who were statistically similar. Age-related changes comparing younger and older age groups within each sex and racial group indicated a significant decrease in mean PMI with increasing age in black and Hispanic women. The mean PMI in white men increased with advancing age.

Adult↗

PubMed1991

"Machismo," self-esteem, education and high maximum drinking among anglo, black and Mexican-American male drinkers.

This study seeks to clarify the relevance of machismo to patterns of high maximum drinking among male drinkers. Specifically, the study describes the psychometric properties of a newly developed 7-item machismo measure, compares levels of machismo and self-esteem for a sample of Anglo, black and Mexican-American males, and examines both main and interaction effects of machismo, self-esteem and education as predictors of alcohol use in these racial/ethnic subgroups. Logistic regression analyses document interaction between race/ethnicity, machismo, self-esteem and education, which calls into question the presumed importance of machismo as a cultural element causing heavy drinking patterns among Mexican-American males.

Adult↗

PubMed1991

Surface detail reproduction of Type IV dental stones with selected polyvinyl siloxane impression materials.

Four polyvinyl siloxane impression materials and 14 modified Type IV dental stones were evaluated for their abilities to reproduce surface detail. Each combination of impression material and dental stone was used to duplicate a 20-microns-wide line. Surface detail reproduction was observed by two paired-rater groups. The line was reproduced in all impression material specimens, but in only 32% of the stone cast specimens. Some combinations of impression material/dental stone reproduced the line all or most of the time, but 12 combinations did not reproduce the line at all.

Calcium Sulfate↗

PubMed1990

Dichloroacetate increases glucose use and decreases lactate in developing rat brain.

Dichloroacetate (DCA) activates pyruvate dehydrogenase (PDH) by inhibiting PDH kinase. Neutralized DCA (100 mg/kg) or saline was intravenously administered to 20 to 25-day-old rats (50-75g). Fifteen minutes later a mixture of [6-14C]glucose and [3H]fluorodeoxyglucose (FDG) was administered intravenously and the animals were sacrificed by microwave irradiation (2450 MHz, 8.0 kW, 0.6-0.8 sec) after 2 or 5 min. Brain regional rates of glucose use and metabolite levels were determined. DCA-treated rats had increased rates of glucose use in all regions studied (cortex, thalamus, striatum, and brain stem), with an average increase of 41%. Lactate levels were lower in all regions, by an average of 35%. There were no significant changes in levels of ATP, creatine phosphate, or glycogen in any brain region. Blood levels of lactate did not differ significantly between the DCA- and the saline-treated groups. Blood glucose levels were higher in the DCA group. In rats sacrificed by freeze-blowing, DCA treatment caused lower brain levels of both lactate and pyruvate. These results cannot be explained by any systemic effect of DCA. Rather, it appears that in the immature rat, DCA treatment results in activation of brain PDH, increased metabolism of brain pyruvate and lactate, and a resulting increase in brain glycolytic rate.

Animals↗

PubMed1990

A computer program for calculating kappa: application to interexaminer agreement in periodontal research.

The kappa statistic is a frequently used measure of interobserver agreement when two or more observers are asked to rate the same items or subjects on some criterion. The advantage of the kappa statistic over simple agreement is that it corrects for agreement by chance. In dental research, because multiple examiners may be involved in assessing subject variables such as attachment loss, bleeding on probing, or periodontal pocket depth, some statistical measure of agreement is needed. The program described here was developed for estimating agreement among periodontal examiners, but also could be used in clinical teaching applications. Assumptions and limitations of the kappa statistic are discussed. Examples of outputs illustrate applications of the program.

Humans↗