Biomedical subjects

T J Prihoda

Publications and source records attributed to T J Prihoda.

At least 73 records · Page 4Linked to original sources

PubMed1987

Effectiveness of adenoidectomy and tympanostomy tubes in the treatment of chronic otitis media with effusion.

To study the effectiveness of adenoidectomy and of the placement of tympanostomy tubes in the treatment of chronic otitis media with effusion, we randomly assigned 578 children, aged four through eight years, to receive bilateral myringotomy and no additional treatment (Group 1), placement of tympanostomy tubes (Group 2), adenoidectomy (Group 3), or adenoidectomy and placement of tympanostomy tubes (Group 4). The 491 children who underwent one of these treatments were examined at six-week intervals for up to two years. The mean time spent with effusion of any type in either ear over the two-year follow-up in the four groups was 51, 36, 31, and 27 weeks, respectively (P less than 0.0001), comparing Group 1 with each of the other groups. Hearing was equivalent in Groups 2, 3, and 4, and was significantly better than in Group 1. The most frequent sequela, purulent otorrhea, occurred one or more times in 22, 29, 11, and 24 percent of the subjects in Groups 1, 2, 3, and 4, respectively (P less than 0.001). Adenoidectomy plus bilateral myringotomy lowered the overall post-treatment morbidity (as measured by hearing acuity in the most severely affected ear [P = 0.0174] and the number of surgical retreatments required [P = 0.009]) more than did tympanostomy tubes alone and to the same degree as did adenoidectomy and tympanostomy tubes. We conclude that adenoidectomy should be considered when surgical therapy is indicated in children four to eight years old who are severely affected by chronic otitis media with effusion.

Adenoidectomy↗

PubMed1987

Effects of dietary cholesterol and fat, sex and sire on lecithin-cholesterol acyltransferase activity in baboons.

We analyzed the effects of dietary cholesterol, type of dietary fat, sex and sire progeny family on lecithin-cholesterol acyltransferase activity in 80 adult baboons. The animals were the progeny of 80 dams and 6 sires and were randomly assigned at birth to breast feeding or to one of three formulas containing 0.02, 0.30 or 0.60 mg cholesterol/ml. After weaning at 4 months of age the animals were fed one of four diets that were either high or low in cholesterol with 40% of the calories from either saturated or unsaturated fat. The fractional and molar rates of lecithin-cholesterol acyltransferase activity were measured at 7-8 years of age by an HPLC method. Infant diet (breast vs. formula feeding or level of cholesterol in formula had no effect on enzyme activity later in life. The adult diets that were high in cholesterol decreased the fractional lecithin-cholesterol acyltransferase rate by 20% / compared to diets low in cholesterol (7.89 vs. 9.84%/h, P less than 0.002), but dietary cholesterol did not affect the molar activity. Animals fed the high cholesterol diets had higher unesterified cholesterol concentrations compared to those fed the low cholesterol diets (38.1 mg/dl vs. 31.6 mg/dl, P less than 0.0001). The molar lecithin-cholesterol acyltransferase rate was increased 13% by saturated compared to unsaturated fat (83.3 vs. 73.6 nmol/h per ml plasma, P less than 0.07), but no effect of dietary fat was observed on the fractional enzyme activity. Females compared to males had significantly higher fractional (10.9 vs. 7.14%/h, P less than 0.0001) and molar lecithin-cholesterol acyltransferase activities (99.3 vs. 61.7 nmol/h per ml plasma, P less than 0.0001). After adjustment for the effects of diet and sex we observed differences in the fractional activity (range, 7.2-10.8%/h, P less than 0.04) and in the molar rate (range, 63.6-99.8 nmol/h per ml plasma, P less than 0.07) among the six sire progeny groups. The differences among sire progeny groups are evidence for genetic differences in lecithin-cholesterol acyltransferase activities among the baboon families.

Animals↗

PubMed1987

Interpretation of bitewing radiographs: application of the kappa statistic to determine rater agreements.

The interrater agreement of 34 dentists in determining the presence or absence of caries and the depth of caries in bitewing radiographs was studied. The kappa statistic was used to determine rater agreement, and results indicate that there was substantial agreement on the presence or absence of caries and only fair agreement on the specific depth of caries. Because of the degree of disagreement in determination of the extent of caries among examiners, it is recommended that this fact be taken into account in relation to the findings on bitewing radiographs, particularly when there may be differences of opinion between parties.

Dental Caries↗

PubMed1987

Sonographic amniotic fluid measurement and fetal growth retardation: a reappraisal.

Sonographic estimation of amniotic fluid volume is commonly used as a diagnostic test for oligohydramnios associated with fetal malnutrition. However, methods of measurement and diagnostic criteria are controversial. We prospectively evaluated the reproducibility of amniotic fluid diameter measurement and studied various threshold definitions of oligohydramnios as predictors of small for gestational age fetuses or fetuses with low ponderal index values. An average of the vertical and two perpendicular horizontal diameters of the largest pocket of amniotic fluid was more reproducible than the maximum vertical pocket and better enabled a single observer to differentiate between patients. An average diameter of 10 mm was highly diagnostic of small for gestational age fetuses but was insufficiently sensitive (27%) to serve as a screening test. Although also of limited sensitivity (40%), an average diameter of approximately 30 mm was probably the best screening threshold. Reduced average diameter was significantly related to the occurrence of a ponderal index less than or equal to the tenth percentile for dates. Three of seven (43%) neonates with a ponderal index less than or equal to the tenth percentile and a birth weight greater than the tenth percentile for dates had a low average diameter, suggesting that reduced average amniotic fluid diameter may help to identify the malnourished fetus with birth weight greater than the tenth percentile for dates.

Amniotic Fluid↗

PubMed1987

Postprandial glucose and insulin responses to glucose polymers by premature infants.

Previous studies have questioned whether neonatal infants can digest and absorb glucose polymers (GP). Thirteen infants of 33-42 weeks of corrected gestational age were fed two glucose polymers with different dextrose equivalents (DE) and glucose. Postprandial glucose and insulin responses were measured consecutively after each feeding. At 60 min, glucose, glucose polymer DE 15 and glucose polymer DE 24 produced serum glucose responses of 138.1, 111.6 and 120 mg/100 ml, respectively. Differences in mean serum glucose and insulin levels were found when glucose or glucose polymers were used as the test carbohydrate. Glucose polymer DE 24 produced a hormonal response closer to that of glucose. This suggests that glucose polymers were hydrolyzed and absorbed and evoked a sufficient glucose and insulin response. Therefore, these glucose polymers would seem to be suitable for use in feeding neonatal infants.

Blood Glucose↗

PubMed1987

Fluid balance and the adult respiratory distress syndrome.

This study examined the effect of fluid balance on survival in ARDS. Of the 213 patients entered into a prospective data collection study, we evaluated 113 patients who met strict criteria for ARDS. Multiple variables were analyzed for as long as 14 days after intubation including cardiac output, pulmonary capillary wedge pressure, mean blood pressure, intake minus output (I-O), cumulative intake minus output (cum I-O), and change in weight (delta wt). We found significant differences in cum I-O and delta wt between survivors and nonsurvivors on almost every day. Survivors lost weight and had a significantly lower cum I-O compared with nonsurvivors. Logistic regression was used to determine if delta wt and cum I-O could predict survival. Patients who lost 3 kg or more weight had a much higher survival than did those who gained 3 kg or more weight (67 and 0%, respectively, on Day 14). Similar results were obtained using comparably low and high values for cum I-O. The logistic regression equations demonstrated that weight loss and low cumulative I-O correlated with improved survival. Although cause and effect relationships are difficult to determine from these types of analyses, they can be used to formulate prospective studies and predict survival in patients.

Body Weight↗

PubMed1987

Comparative radiographic study of human and animal long bone patterns.

The objective of this study was to test the hypothesis that certain radiographic features can be found to distinguish between human and animal long bone fragments, and therefore would be useful as an adjunct in forensic science identification. Using proposed radiographic criteria, 13 archeologists and 12 dentists were asked to identify 20 radiographic samples as representing human or animal bone. Results showed that archeologists correctly identified 86.8% of the samples, and dentists correctly identified 81.9%. Based on the results of this study, it was concluded that radiographic interpretation of long bone fragments may be a useful aid in a forensic science investigation of human and animal remains.

Animals↗

PubMed1986

Histologic and hormonal documentation of the luteinized unruptured follicle syndrome.

Histologic and hormonal documentation of a luteinized unruptured follicle that occurred during a spontaneous menstrual cycle in a rhesus monkey is presented. Frequent (every 2 hours) blood sampling to assess midcycle hormonal dynamics in the monkey with the luteinized unruptured follicle and in five monkeys with an ovulatory stigma revealed significant aberrations in the gonadotropin and steroid hormone profiles associated with a luteinized unruptured follicle. Although the midcycle 17 beta-estradiol surge was normal, the monkey with the luteinized unruptured follicle demonstrated (1) blunted midcycle bioassayable luteinizing hormone, immunoassayable luteinizing hormone, and follicle-stimulating hormone surges; (2) absence of disparity in the bioassayable luteinizing hormone: immunoassayable luteinizing hormone ratio during the gonadotropin surge; (3) absence of progesterone and 17 alpha-hydroxyprogesterone secretion during the gonadotropin surge; and (4) delayed and blunted rise in progesterone and 17 alpha-hydroxyprogesterone after the gonadotropin surge. These findings suggest that an impaired luteinizing hormone surge, perhaps mediated by insufficient midcycle progestin secretion, is one possible cause of the luteinized unruptured follicle syndrome.

17-alpha-Hydroxyprogesterone↗

PubMed1986

Post-tympanostomy otorrhea.

Otorrhea is the most common complication of surgical drainage of the tympanum for the treatment of chronic secretory otitis media. Otorrhea present at the first postoperative visit may be due to the operative procedure, the underlying disease process, or both. After analyzing data from 525 operations on 1045 ears of 396 children with chronic secretory otitis media, and finding an over-all incidence of immediate postoperative otorrhea of 3.4%, we conclude that preparations of the ear canal with povidone iodine and the postoperative prophylactic use of an antimicrobial-corticosteroid topical preparation provides optimal control of postoperative wound infection. Sporadic increases in the incidence of postoperative otorrhea may be due to extrinsic factors such as outbreaks of upper respiratory infection.

Adenoidectomy↗

PubMed1986

Analysis of birth weight percentile as a predictor of perinatal outcome.

Birth weight-gestational age tables are convenient methods for the neonatal evaluation of intrauterine growth, however, the limits of acceptable birth weight for gestational age are controversial. The purpose of this study was to identify the birth weight percentiles that accurately predicted poor perinatal outcome from 28 through 41 weeks' gestational age. In a homogeneous population of 44,811 patients, the birth weight percentile that predicted poor perinatal outcome varied with gestational age. The birth weight percentile that predicted normal outcome in 80% of normal patients declined from the 55th percentile at 28 to 29 weeks to the 24th percentile at 34 to 35 weeks. From 28 through 35 weeks' gestational age, possibly owing to the confounding effects of prematurity, patients classified as normal by birth weight criteria still had a significant risk of poor outcome. After 36 weeks' gestational age, poor perinatal outcome occurred in 3.9% of patients and tended to occur at the extremes of birth weight. Classification by birth weights approximating the tenth and 90th percentiles identified a population in which the majority of the poor perinatal outcome occurred. However, poor outcome occurred in only 10% of patients with birth weights below the tenth or above the 90th percentiles. Among those with birth weights between the tenth and 90th percentiles, outcome was normal in 98%. Therefore, from 36 through 41 weeks' gestational age, the prevalence of poor perinatal outcome was low, and birth weight percentile was a weak predictor of outcome in the individual patient.

Birth Weight↗

PubMed1985

Periovulatory hormonal dynamics: relationship of immunoassayable gonadotropins and ovarian steroids to the bioassayable luteinizing hormone surge in rhesus monkeys.

The relationship between ovarian steroids and LH during the midcycle gonadotropin surge is controversial. Recent demonstration of temporal and quantitative differences in immunoassayable LH (I-LH) and bioassayable LH (B-LH) at midcycle have further clouded this issue. To evaluate the relationship of I-LH, FSH, and ovarian steroids to the onset of the midcycle B-LH surge, blood samples were obtained from five chronically catheterized rhesus monkeys at 2-h intervals for 5-6 days. The plasma was assayed for FSH, LH, 17 beta-estradiol (E2), progesterone (P4), and 17 alpha-hydroxyprogesterone (17-OHP) by RIA and for LH by a rat interstitial cell testosterone in vitro bioassay. The initiation of the B-LH surge served as time zero (to) for the temporal analysis of changes in plasma hormone levels. The I-LH and FSH surges were initiated 6.4 +/- 2.2 h (mean +/- SEM) and 5.2 +/- 1.9 h, respectively, after the onset of the B-LH surge. Although the duration of the ascending limb of the surge was similar for B-LH, I-LH, and FSH, the mean +/- SEM total duration of the B-LH surge (34.5 +/- 3.5 h) was significantly longer (P less than 0.025) than those of I-LH (24.4 +/- 5.0 h) and FSH (27.6 +/- 2.3 h). Before the onset of the B-LH surge (to - 4 h), the ratio of B-H to I-LH was unity; however, during the acme of gonadotropin secretion (to + 12-16 h), the B-LH to I-LH ratio approached 6:1. Doubling times for B-LH, I-LH, and FSH were similar during the ascending phase of the surge. Plasma E2 concentrations increased continuously from to - 40 h to to, with a mean +/- SEM doubling time of 32.6 +/- 4.7 h. Peak E2 concentrations occurred within 6 h after the onset of the B-LH surge. Plasma P4 concentrations began to increase at to - 6 h in four monkeys and at to in one monkey. Plasma P4 concentration plateaued from to to to + 24 h, then increased rapidly, with a mean +/- SEM doubling time of 20.5 +/- 2.9 h. Although there were significant individual variations in plasma 17-OHP concentrations, a definite increase in 17-OHP occurred by to - 10 h, and peak concentrations occurred at to + 1 h.(ABSTRACT TRUNCATED AT 400 WORDS)

17-alpha-Hydroxyprogesterone↗

PubMedDate not supplied

Ondansetron for reduction of drinking among biologically predisposed alcoholic patients: A randomized controlled trial.

CONTEXT: Early-onset alcoholism differs from late-onset alcoholism by its association with greater serotonergic abnormality and antisocial behaviors. Thus, individuals with early-onset alcoholism may be responsive to treatment with a selective serotonergic agent. OBJECTIVE: To test the hypothesis that drinking outcomes associated with early vs late-onset alcoholism are differentially improved by the selective 5-HT(3) (serotonin) antagonist ondansetron. DESIGN: Double-blind, randomized, placebo-controlled clinical trial. SETTINGS: University of Texas Health Science Center in Houston (April 1995-June 1998) and University of Texas Health Science Center in San Antonio (July 1998-December 1999). PARTICIPANTS: A total of 321 patients with diagnosed alcoholism (mean age, 40.6 years; 70.5% male; 78.6% white) were enrolled, 271 of whom proceeded to randomization. INTERVENTIONS: After 1 lead-in week of single-blind placebo, patients were randomly assigned to receive 11 weeks of treatment with ondansetron, 1 microg/kg (n = 67), 4 microg/kg (n = 77), or 16 microg/kg (n = 71) twice per day; or identical placebo (n = 56). All patients also participated in weekly standardized group cognitive behavioral therapy. MAIN OUTCOME MEASURES: Self-reported alcohol consumption (drinks per day, drinks per drinking day, percentage of days abstinent, and total days abstinent per study week); and plasma carbohydrate deficient transferrin (CDT) level, an objective and sensitive marker of transient alcohol consumption. RESULTS: Patients with early-onset alcoholism who received ondansetron (1, 4, and 16 microg/kg twice per day) compared with those who were administered placebo, had fewer drinks per day (1.89, 1.56, and 1.87 vs 3.30; P =.03, P =.01, and P =.02, respectively) and drinks per drinking day (4.75, 4.28, and 5.18 vs 6.90; P =.03, P =.004, and P =.03, respectively). Ondansetron, 4 microg/kg twice per day, was superior to placebo in increasing percentage of days abstinent (70.10 vs 50.20; P =.02) and total days abstinent per study week (6.74 vs 5.92; P =.03). Among patients with early-onset alcoholism, there was a significant difference in the mean log CDT ratio between those who received ondansetron (1 and 4 microg/kg twice per day) compared with those who received the placebo (-0.17 and -0.19 vs 0.12; P =.03 and P =.01, respectively). CONCLUSION: Our results suggest that ondansetron (particularly the 4 microg/kg twice per day dosage) is an effective treatment for patients with early-onset alcoholism, presumably by ameliorating an underlying serotonergic abnormality. JAMA. 2000;284:963-971

Adult↗

PubMedDate not supplied

Interaction of hyperthermia with Taxol in human MCF-7 breast adenocarcinoma cells.

Hyperthermia treatments (43 degrees C, 1 h) were performed on exponentially growing MCF-7 breast adenocarcinoma cells at the beginning, middle, or end of 24 h incubations of the cells in vitro with Taxol (paclitaxel). When the cells were heated at the beginning or middle of the Taxol incubation, the hyperthermia treatment protected against the toxic effect of each of the Taxol concentrations examined (5, 10 and 100 nM). Consistent with earlier studies, Taxol treatment at 37 degrees C resulted in an accumulation of greater than 94% of the cells in G2/M at 24 h. Heating the cells at the middle or end of the Taxol treatment resulted in a similar accumulation. However, heat treatment during the first hour of Taxol exposure resulted in a significantly smaller percentage of cells (approximately 50%) in G2/M. HPLC analysis showed that at 37 degrees C, Taxol uptake into MCF-7 cells approached maximum within 0.25 h and increased only slightly more over the next 11.75 h. The parental Taxol level was markedly lower by 24 h. In contrast, 1 h hyperthermia treatments at the beginning or middle of the Taxol incubation resulted in higher Taxol concentrations at 12 and 24h, and higher intracellular concentrations overall than at 37 degrees C. These results indicate that hyperthermia inhibits Taxol related cell cycle effects and cytotoxicity, in spite of causing higher concentrations of Taxol to be present in heated cells.

Adenocarcinoma↗

PubMedDate not supplied

A naturalistic study of the relationships among electromyographic activity, psychological stress, and pain in ambulatory tension-type headache patients and headache-free controls.

Twelve subjects who met diagnostic criteria for episodic tension-type headache and nine subjects who rarely or never suffered from headaches wore a computer-controlled electromyographic (EMG) activity recorder in their natural environment for 48 to 96 consecutive hours. EMG activity of the posterior neck or frontal muscles was recorded 24 hr per day. During waking hours, subjects rated their perceived levels of stress, pain, and negative affect at 30-min intervals. The EMG activity of headache and control subjects did not differ significantly, and EMG activity did not covary with stress, pain, or negative affect. Cross-correlations among EMG activity, pain, and stress revealed little evidence of leading, contemporaneous, or lagging relationships. Interrupted time series analysis showed no consistent muscle hyperactivity during a headache attack compared to a headache-free baseline period.

Adult↗

PubMedDate not supplied

Efficacy of acoustic reflectometry in detecting middle ear effusion.

The acoustic otoscope measures the amount of sound reflected from the tympanic membrane. Since the amount of reflected sound is increased by fluid in the middle ear, it seemed likely that the acoustic otoscope could be used for detection of otitis media. We compared acoustic reflectometry with over 4,000 tympanometric and otoscopic examinations in 451 children who were examined at regular intervals following surgery for chronic otitis media with effusion. The data indicate a lower sensitivity and specificity of acoustic reflectometry than had been reported previously. The receiver-operator characteristics of this device are discussed.

Acoustic Impedance Tests↗

PubMedDate not supplied

The Environmental Exposure and Sensitivity Inventory (EESI): a standardized approach for measuring chemical intolerances for research and clinical applications.

The lack of a generally accepted case definition for multiple chemical sensitivity (MCS) and the absence of a standardized approach for measuring salient aspects of chemical sensitivity that would permit cross-comparison of findings by different investigators have hindered progress in this area. Based upon findings from an earlier study of 112 persons with self-reported chemical sensitivity who attributed their chemical sensitivity to a well-defined exposure event, we developed an instrument with self-rating scales to assess Symptom Severity, Chemical (Inhalant) Intolerances, Other Intolerances (e.g., foods, medications, alcohol), Life Impact, and Masking (a measure of ongoing chemical exposures). When administered to four patient groups and controls, the scales showed good reliability and validity overall (n = 421) and in each group. Used together, the scales provided sensitivity of 92% and specificity of 95% in differentiating chemically sensitive persons from controls. Our results support use of these scales individually or collectively for a variety of applications including the selection of chemically sensitive subjects and controls for research, assessment of chemical sensitivity in various study populations, cross-comparison of groups studied by different investigators, pre- and post-assessment of therapeutic interventions, clinical evaluation of complex patients who report intolerances, and teaching medical residents and students how to evaluate patients for chemical sensitivity and MCS.

Environmental Exposure↗

PubMedDate not supplied

A controlled comparison of symptoms and chemical intolerances reported by Gulf War veterans, implant recipients and persons with multiple chemical sensitivity.

Using the Environmental Exposure and Sensitivity Inventory (EESI), a standardized instrument for measuring chemical sensitivity, we obtained and compared ratings of symptoms, chemical (inhalant) intolerances, other intolerances (e.g., drugs, caffeine, alcohol, skin contactants), lifeimpact, and masking (ongoing exposures) in five populations: multiple chemical sensitivity (MCS) patients who did (n = 96) or did not (n = 90) attribute onset of their illness to a specific exposure event, patients with implanted devices (n = 87), Gulf War veterans (n = 72), and controls (n = 76). For each patient group, mean scores on the first four scales were significantly greater than for controls. MCS patients reported avoiding more chemical exposures (were less masked) than the other groups. Across groups, for a given level of symptoms, as masking increased, mean scores on the Chemical Intolerance Scale decreased. In contrast, mean scores on the Other Intolerance Scale appeared to be less affected by masking. These findings suggest that some patients with antecedent chemical exposures, whether exogenous (chemical spill, pesticide application, indoor air contaminants) or endogenous (implant), develop new chemical, food, and drug intolerances. Reports of new caffeine, alcohol, medication, food, or other intolerances by patients may signal exposure-related illness. Masking may reduce individuals' awareness of chemical intolerances, and, to a lesser degree, other intolerances.

Adult↗

PubMedDate not supplied

Cardiopulmonary and intravascular alterations during the sustained infusion of PAF.

The physiologic responses during prolonged exposure to platelet activating factor (PAF) are largely unexplored. Thus, the cardiopulmonary and intravascular effects of a sustained infusion of 1-O-hexadecyl-2-acetyl-sn-glycero-3- phosphocholine (C16:0-AGEPC; 0.159 nmole/kg/min for 120 min) were characterized in anesthetized rabbits. Within minutes, a transient period of tachypnea developed and was followed by 30 min of stable ventilation. Subsequently, both respiratory rate and tidal volume irreversibly increased. The latter pulmonary ventilatory alterations were preceded by lung mechanical changes, i.e., dynamic lung compliance (CLdyn) decreased 21.6 +/- 3.4% (mean +/- SE) and total pulmonary resistance (Rpulm) increased 25.1 +/- 8.5%. In contrast to CLdyn which partially recovered during infusion, Rpulm remained elevated throughout the study, Concurrent with these pulmonary alterations, significant cardiovascular changes also occurred. Right ventricular hypertension developed immediately and was maximal within 7.9 +/- 0.9 min; this hypertension persisted throughout the infusion period but rapidly reversed thereafter. Mean arterial pressure (MAP) decreased 37.1 +/- 5.8% within 31.4 +/- 2.5 min and then remained at this level. The patterns and extent of alterations in left ventricular pressure, +dP/dtmax, and -dP/dtmax paralleled the changes in MAP and were accompanied by a progressive decrease in left ventricular end-diastolic pressure. These cardiopulmonary effects of C16:0-AGEPC developed in association with prolonged thrombocytopenia and intravascular platelet activation. In contrast, C16:0-AGEPC-induced neutropenia at 5 min was reversed within 60 min and was followed by sustained neutrophilia. In combination, these data suggest that the continuous biosynthesis and release of PAF in vivo could modulate significant, persistent pathophysiological alterations.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗