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Subchronic inhalation toxicology of ethylene glycol monoethyl ether in the rat and rabbit.

The subchronic inhalation toxicology of ethylene glycol monoethyl ether (EGEE) was evaluated in rats and rabbits using a 13-week exposure regimen. Groups of 20 rabbits (10 M, 10 F) and 30 rats (15 M, 15 F) were exposed to a vapor of 25 ppm, 100 ppm, or 400 ppm, 6 hr/day, 5 days/week. The control groups received air only. Physical examinations and body weight measurements were conducted on all animals pretest and weekly throughout the study. Ophthalmoscopic examination was performed pretest and at termination. Evaluation of hematology and clinical chemistry was conducted on 10 animals per sex per group from each species after 13 weeks of study. Histopathological changes were assessed for all animals from the high-dose and control groups. In addition, selected tissues were examined from all animals from the mid- and low-dose groups. Both species exhibited an increased incidence of lacrimation and mucoid nasal discharge, but the response was not consistently dose-related. Rats exposed to EGEE showed no compound-related effects except for a decrease in pituitary to body weight ratio for high-dose males and a decrease in absolute spleen weight for all female animals. The spleen to body weight ratio was also less than controls for the females in the low- and high-dose groups. Pathological changes supportive of these organ weight changes were not observed. The rabbit is the more sensitive species to the subchronic toxicological effects from EGEE. Mean body weight values for low- and high-dose animals were decreased; the mid-dose animals, however, showed no change.(ABSTRACT TRUNCATED AT 250 WORDS)

Air Pollutants, Occupational↗

Spontaneous ophthalmic lesions in young Sprague-Dawley rats.

Eight hundred eight Sprague-Dawley rats were examined for ophthalmic abnormalities during a pretest period in various preclinical safety assessment studies. Persistent pupillary membrane, corneal crystal, healed minor trauma, synechia, coloboma of the iris, lens luxation, cataract, persistent hyperplastic primary vitreous, vitreous hemorrhage, coloboma of the optic disc or choroid, remnant of hyaloid arterial system, retinal hemorrhage, retinal detachment, retinal folding and choroidal defect were observed. The incidences of corneal crystal, synechia, and nuclear cataract in this survey were higher than those reported previously. On the other hand, retinal folding in this survey was less common than that reported previously. These results suggest that background data of eye problems in albino rats should be accumulated in each own laboratory colony. In addition, since spontaneous eye problems are common in young albino rats, elimination of rats with ophthalmic abnormalities from study groups by an ophthalmic examination during a pretest period would facilitate to evaluate toxicity potential of test compounds in safety assessment studies.

Animals↗

Changing homophobic attitudes through college sexuality education.

It was hypothesized that a unit on homosexuality (which emphasized role playing and the debunking of myths) in an undergraduate college sexuality course would alter students' homophobic attitudes. A modified version of the Hudson/Ricketts Index of Homophobia was used to measure homophobia. At the completion of the course, for those students in the treatment group with pretest scores above the median, the homophobic scores decreased significantly when compared to the scores of control counterparts. The results of this study also showed that there was no significant difference in homophobia scores at the end of the course for those students in the treatment group with pretest scores below the median when compared to the appropriate controls.

Adolescent↗

Impact of information and weekly contact on attitudes of Korean general educators and nondisabled students regarding peers with disabilities.

Effects of written information and weekly special educator contact on general educators in Seoul, Korea was examined. Special educators prepared a weekly newsletter to educate teachers on how to include children with disabilities in their classrooms for part of the day. Participants were 30 general educators and 300 nondisabled peers of the students with disabilities. A pretest-posttest control group was used to assess teacher efficacy, attitudes of general educators toward inclusion, and peer acceptance of children with disabilities. We conducted ANCOVAS on posttest scores of three measures, considering pretest scores of each survey as the covariate. General educators in the information group showed significantly higher scores in teacher-efficacy and attitudes toward inclusion. Their nondisabled students showed significantly higher acceptance scores than did controls.

Adult↗

Deaf students' recall of Spanish vocabulary under three testing conditions.

This investigation examined the effects of three training conditions on deaf students' recall of Spanish word meaning as measured by performance on a Spanish vocabulary test. The conditions were; a) repeated written productions, b) repeated fingerspelling, and c) repeated silent reading of selected Spanish words and their English equivalents. Subjects were 30 deaf undergraduate students enrolled in introductory Spanish courses at Gallaudet University in Washington, DC. Researchers assigned 10 subjects to each of the 3 training groups. A 30 item pretest was administered to verify that the vocabulary was not known to the subjects. A posttest containing 25 items from the pretest was administered twice to the subjects. For short-term memory there were no statistically significant differences across the 3 conditions. For long-term memory scores under the repeated written condition were significantly higher than scores under fingerspelling and silent reading conditions. The use of a study strategy incorporating writing may enhance the learning of Spanish vocabulary by deaf college students. The strategy could also be applied to other foreign languages and a range of academic subjects for deaf students.

Deafness↗

Peer counseling in a culturally specific adolescent pregnancy prevention program.

This study evaluated the effects of peer counseling in a culturally specific adolescent pregnancy prevention program for African American females. A random pretest and multiple posttest experimental and comparison group design was used to obtain data on a sample of 63 female African American adolescents, ages 12 to 16, who lived in four public housing developments. Descriptive data and tests of significance revealed that none of the participants who received peer counseling became pregnant within three months of the intervention. Findings revealed a statistically significant increase in reproductive and other self-related knowledge topics among the experimental group when comparing pretest and eight-week posttest scores. Most participants had not had sexual intercourse; the average age of sexual onset was 12 years in the experimental group and 11 years in the controls. Designing and implementing culturally specific adolescent pregnancy prevention programs for adolescents younger than age 11 and/or before sexually active seems appropriate.

Adolescent↗

Measurement of urinary metanephrines to screen for pheochromocytoma in an unselected hospital referral population.

BACKGROUND: Despite the rarity of pheochromocytoma, diagnosis is important because of the dangers of uncontrolled severe hypertension and the availability of very effective surgical treatment. Urinary or plasma catecholamines or catecholamine derivatives are commonly used to screen for pheochromocytomas before imaging, but data from 24-h urinary metanephrine results, patient age, and sex may better predict tumors in populations with a low pretest probability. METHODS: We retrospectively studied outcomes of an unselected population (1819 patients) referred to a tertiary hospital laboratory for urinary metanephrine testing and investigated the usefulness of some simple derivative measures for detecting pheochromocytoma. We normalized values for urinary 24-h excretion of metanephrine, normetanephrine, and 3-methoxytyramine by dividing by an age- and sex-specific reference range. We then compared pheochromocytoma prediction by the use of products of these normalized measures with the gold standard of biopsy-confirmed tumor. RESULTS: The product of the excretion of normalized metanephrine (nMAD) and normalized normetanephrine (nNMT) (nMAD.nNMT) was a highly sensitive (100%) and specific (99.1%) measure, yielding a positive predictive value of 82%. ROC curves were not improved by including the normalized 3-methoxytyramine concentrations in the product. The test for nMAD.nNMT gave higher sensitivity and specificity than the tests for either substance alone. CONCLUSION: The test for nMAD.nNMT is a useful measure for identifying pheochromocytoma in a population with a low pretest probability.

Adrenal Gland Neoplasms↗

Prevalence of symptoms and risk of sleep apnea in primary care.

BACKGROUND: To obtain prevalence estimates for key symptoms and features that can indicate the presence of obstructive sleep apnea (OSA) in a broad range of primary care settings. DESIGN: Cross-sectional survey. SETTING: Forty offices and clinics in the United States, Germany, and Spain. PARTICIPANTS: Consecutive patients who were > 15 years of age, regardless of the reason for the visit. MEASUREMENTS: We collected demographic information, prevalence of self-reported chronic snoring, sleepiness, obesity (body mass index [BMI] > 30), hypertension, and calculation of OSA risk, and we also compared results between the United States and Europe. RESULTS: There was a 78% return rate for 8,000 surveys (mean age, 51 years; age range, 15 to 98 years; 52% women). One third of participants (32%) had a high pretest probability for OSA, with a higher rate in the United States (35.8% of 3,915 participants) than in Europe (26.3% of 2,308 participants; p < 0.001; age-matched and sex-adjusted odds ratio [OR], 1.37; 95% confidence interval [CI], 1.16 to 1.61). Sleepiness (32.4% vs 11.8%, respectively; p < 0.001) followed by obesity and/or hypertension (44.8% vs 37.1%, respectively; p < 0.01) contributed to the OSA risk difference between participants in the United States and Europe, as frequent snoring and breathing pauses were similarly reported (44%). A high pretest probability for OSA was more often present in men than in women (37.9% vs 27.8%, respectively; p < 0.005; OR, 1.96; CI, 1.59 to 2.88) and in those that were obese (ie, BMI, > or = 30 kg/m(2)), a condition that is generally more common in the US population than in the European population (27.9% vs 17.2%, respectively; p < 0.01). CONCLUSIONS: Primary care physicians in the United States and Europe will encounter a high demand for services to confirm or manage sleep apnea, sleepiness, and obesity.

Europe↗

Clinical prediction model to characterize pulmonary nodules: validation and added value of 18F-fluorodeoxyglucose positron emission tomography.

BACKGROUND: The added value of 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) scanning as a function of pretest risk assessment in indeterminate pulmonary nodules is still unclear. OBJECTIVE: To obtain an external validation of the prediction model according to Swensen and colleagues, and to quantify the potential added value of FDG-PET scanning as a function of its operating characteristics in relation to this prediction model, in a population of patients with radiologically indeterminate pulmonary nodules. DESIGN, SETTING, AND PATIENTS: Between August 1997 and March 2001, all patients with an indeterminate solitary pulmonary nodule who had been referred for FDG-PET scanning were retrospectively identified from the database of the PET center at the VU University Medical Center. RESULTS: One hundred six patients were eligible for the study, and 61 patients (57%) proved to have malignant nodules. The goodness-of-fit statistic for the model (according to Swensen) indicated that the observed proportion of malignancies did not differ from the predicted proportion (p = 0.46). PET scan results, which were classified using the 4-point intensity scale reading, yielded an area under the evaluated receiver operating characteristic curve of 0.88 (95% confidence interval [CI], 0.77 to 0.91). The estimated difference of 0.095 (95% CI, -0.003 to 0.193) between the PET scan results classified using the 4-point intensity scale reading and the area under the curve (AUC) from the Swensen prediction was not significant (p = 0.058). The PET scan results, when added to the predicted probability calculated by the Swensen model, improves the AUC by 13.6% (95% CI, 6 to 21; p = 0.0003). CONCLUSION: The clinical prediction model of Swensen et al was proven to have external validity. However, especially in the lower range of its estimates, the model may underestimate the actual probability of malignancy. The combination of visually read FDG-PET scans and pretest factors appears to yield the best accuracy.

Aged↗

Prospective study of the diagnostic accuracy of the simplify D-dimer assay for pulmonary embolism in emergency department patients.

OBJECTIVE: To determine if a d-dimer assay (Simplify D-dimer; Agen Biomedical; Brisbane, Australia) can reliably exclude pulmonary embolism (PE) by producing a posttest probability of PE < 1% in low-risk, symptomatic emergency department (ED) patients. METHODS: Hemodynamically stable patients were evaluated for PE using a structured d-dimer-centered protocol; d-dimer testing was performed prior to imaging. Prior to testing, physicians completed an electronic data form that included their unstructured clinical estimate for the pretest probability of PE (< 15%, 15 to 40%, or > 40%) and the elements of the Charlotte rule and Canadian score for PE. Criterion standard was selective use of pulmonary vascular imaging and 90-day follow-up. RESULTS: We enrolled 2,302 patients (mean age, 45 +/- 16 years [+/- SD]; 31% male); 108 patients received a diagnosis of PE (4.7%; 95% confidence interval [CI], 3.6 to 5.6%). The overall sensitivity and specificity of the d-dimer assay were 80.6% (95% CI, 71.8 to 87.5%) and 72.5% (95% CI, 70.6 to 74.4%), respectively. The negative likelihood ratio and negative predictive value were 0.27 (95% CI, 0.18 to 0.39) and 98.7% (95% CI, 98.0 to 99.1%), respectively. The posttest prevalence of PE among low-risk patients with negative d-dimer results was 0.7% (95% CI, 0.3 to 1.4%) for the unstructured estimate, 1.2% (95% CI, 0.7 to 2.0%) for the Canadian score, and 1.1% (95% CI, 0.6 to 1.7%) for the Charlotte rule. CONCLUSIONS: The Simplify D-dimer assay had moderate sensitivity and relatively high specificity for PE in low-risk ED patients. The combination of a physician's unstructured estimate of pretest probability of PE of < 15% and a negative d-dimer result produced a posttest probability of PE of 0.7% (95% CI, 0.3 to 1.4%).

Adult↗

Diagnosis and treatment of deep-vein thrombosis.

Deep-vein thrombosis (DVT) is a common condition that can lead to complications such as postphlebitic syndrome, pulmonary embolism and death. The approach to the diagnosis of DVT has evolved over the years. Currently an algorithm strategy combining pretest probability, D-dimer testing and compression ultrasound imaging allows for safe and convenient investigation of suspected lower-extremity thrombosis. Patients with low pretest probability and a negative D-dimer test result can have proximal DVT excluded without the need for diagnostic imaging. The mainstay of treatment of DVT is anticoagulation therapy, whereas interventions such as thrombolysis and placement of inferior vena cava filters are reserved for special situations. The use of low-molecular-weight heparin allows for outpatient management of most patients with DVT. The duration of anticoagulation therapy depends on whether the primary event was idiopathic or secondary to a transient risk factor. More research is required to optimally define the factors that predict an increased risk of recurrent DVT to determine which patients can benefit from extended anticoagulant therapy.

Algorithms↗

A comparison between two training programs and their effects on fatigue rates in women.

This study investigated the effects of a plyometric training program and a traditional weight-training program on the onset rate of fatigue in the vertical jump in women. Twenty-five untrained college women ranging in age from 18-35 were randomly separated into 3 groups: a plyometric group, a traditional weight-training group, and a control (untrained) group. For the purpose of this study, the traditional weight-training group was defined as performing 3 sets of 10 repetitions at 70% of the subject's 1 repetition maximum (1RM). Training took place over a 10-week period for both the plyometric and traditional weight-trained groups. The plyometric group prolonged the onset of fatigue by 3.85 seconds as compared with their pretest data. The traditional weight-training group fatigued 0.55 seconds faster after training was implemented as compared with their pretest data. These results showed a significant difference between the groups in their onset rates of fatigue (p < 0.05). The results of this study show that a plyometric training program prolongs the onset rate of fatigue in the vertical jump in women as compared with a traditional weight-training program.

Adaptation, Physiological↗

The effects of short-term unilateral and bilateral lower-body resistance training on measures of strength and power.

The purpose of this study was to compare the effects of short-term unilateral resistance training (UL) and bilateral resistance training (BL) with free weights on several tests of unilateral and bilateral lower-body strength and power in men and women. Thirty-eight untrained men and women (mean body mass 78.3 +/- 21.47 kg; age 20.74 +/- 2.6 years) completed the study. The groups trained 2 days per week for 8 weeks with free weights and 2 days per week for 5 of the 8 weeks with plyometric drills. The resistance-training program consisted of a progression from 3 sets of 15 repetitions at 50% of the subject's predicted 1 repetition maximum (1RM) to 6 sets of 5 repetitions at 87% 1RM. Training volume and intensity were equal for each group. The free-weight squat was used to measure unilateral and bilateral strength. Power was measured by the Magaria-Kalamen stair-climb test and the unilateral and bilateral vertical jump test. Analysis of covariance was used to analyze differences between men and women and the interaction of group and gender. Pretest scores were used as the covariate. The UL group improved more than the BL group on the unilateral vertical jump height (p = 0.001) and relative power (p = 0.013). After adjusting for pretest differences, the improved scores on all tests, except for the unilateral squat, were similar between the men and the women. No significant interactions on all tests were found for the men or women comparison between training groups. These results indicate that UL and BL are equally effective for early phase improvement of unilateral and bilateral leg strength and power in untrained men and women.

Adolescent↗

Quantitative analysis of single- vs. multiple-set programs in resistance training.

The purpose of this study was to examine the existing research on single-set vs. multiple-set resistance training programs. Using the meta-analytic approach, we included studies that met the following criteria in our analysis: (a) at least 6 subjects per group; (b) subject groups consisting of single-set vs. multiple-set resistance training programs; (c) pretest and posttest strength measures; (d) training programs of 6 weeks or more; (e) apparently "healthy" individuals free from orthopedic limitations; and (f) published studies in English-language journals only. Sixteen studies generated 103 effect sizes (ESs) based on a total of 621 subjects, ranging in age from 15-71 years. Across all designs, intervention strategies, and categories, the pretest to posttest ES in muscular strength was (chi = 1.4 +/- 1.4; 95% confidence interval, 0.41-3.8; p < 0.001). The results of 2 x 2 analysis of variance revealed simple main effects for age, training status (trained vs. untrained), and research design (p < 0.001). No significant main effects were found for sex, program duration, and set end point. Significant interactions were found for training status and program duration (6-16 weeks vs. 17-40 weeks) and number of sets performed (single vs. multiple). The data indicated that trained individuals performing multiple sets generated significantly greater increases in strength (p < 0.001). For programs with an extended duration, multiple sets were superior to single sets (p < 0.05). This quantitative review indicates that single-set programs for an initial short training period in untrained individuals result in similar strength gains as multiple-set programs. However, as progression occurs and higher gains are desired, multiple-set programs are more effective.

Adolescent↗

The effects of plyometric vs. dynamic stabilization and balance training on power, balance, and landing force in female athletes.

Neuromuscular training protocols that include both plyometrics and dynamic balance exercises can significantly improve biomechanics and neuromuscular performance and reduce anterior cruciate ligament injury risk in female athletes. The purpose of this study was to compare the effects of plyometrics (PLYO) versus dynamic stabilization and balance training (BAL) on power, balance, strength, and landing force in female athletes. Either PLYO or BAL were included as a component of a dynamic neuromuscular training regimen that reduced measures related to ACL injury and increased measures of performance. Nineteen high school female athletes participated in training 3 times a week for 7 weeks. The PLYO (n = 8) group did not receive any dynamic balance exercises and the BAL (n = 11) group did not receive any maximum effort jumps during training. Pretraining vs. posttraining measures of impact force and standard deviation of center of pressure (COP) were recorded during a single leg hop and hold. Subjects were also tested for training effects in strength (isokinetic and isoinertial) and power (vertical jump). The percent change from pretest to posttest in vertical ground reaction force was significantly different between the BAL and PLYO groups on the dominant side (p < 0.05). Both groups decreased their standard deviation of center of pressure (COP) during hop landings in the medial/lateral direction on their dominant side, which equalized pretested side to side differences. Both groups increased hamstrings strength and vertical jump. The results of this study suggest that both PLYO and BAL training are effective at increasing measures of neuromuscular power and control. A combination of PLYO and BAL training may further maximize the effectiveness of preseason training for female athletes.

Adolescent↗

Evaluation of a sexual health approach to prevent HIV among low income, urban, primarily African American women: results of a randomized controlled trial.

This randomized controlled trial evaluated an innovative culturally specific sexual health intervention-targeting, but not limited to, low-income African American women-in which HIV and sexually transmitted disease prevention strategies were combined with comprehensive sexuality education. The intervention was delivered and evaluated in community-based settings to 218 participants randomly assigned to treatment or a no-treatment control group. Participants were interviewed at pretest and 3 and 9 months after the intervention to assess changes in both sexuality and HIV risk variables. The intervention was effective in improving sexual anatomy knowledge at both 3- and 9-month follow-up. For a subset of women engaging in unprotected sex at pretest, the intervention group reported an increase in positive attitudes toward the female condom at 9-month follow-up. Reasons for the weak treatment effect are discussed in the context of challenges inherent in conducting community-based research with high-risk populations and sensitive topics. Recommendations are provided for improving sample attrition, statistical power, and response bias and for altering the intervention so as to strengthen its impact.

Adolescent↗

Perceptual-learning evidence for separate processing of asynchrony and order tasks.

Normal perception depends, in part, on accurate judgments of the temporal relationships between sensory events. Two such relative-timing skills are the ability to detect stimulus asynchrony and to discriminate stimulus order. Here we investigated the neural processes contributing to the performance of auditory asynchrony and order tasks in humans, using a perceptual-learning paradigm. In each of two parallel experiments, we tested listeners on a pretest and a posttest consisting of auditory relative-timing conditions. Between these two tests, we trained a subset of listeners approximately 1 h/d for 6-8 d on a single relative-timing condition. The trained listeners practiced asynchrony detection in one experiment and order discrimination in the other. Both groups were trained at sound onset with tones at 0.25 and 4.0 kHz. The remaining listeners in each experiment, who served as controls, did not receive multihour training during the 8-10 d between the pretest and posttest. These controls improved even without intervening training, adding to evidence that a single session of exposure to perceptual tasks can yield learning. Most importantly, each of the two groups of trained listeners learned more on their respective trained conditions than controls, but this learning occurred only on the two trained conditions. Neither group of trained listeners generalized their learning to the other task (order or asynchrony), an untrained temporal position (sound offset), or untrained frequency pairs. Thus, it appears that multihour training on relative-timing skills affects task-specific neural circuits that are tuned to a given temporal position and combination of stimulus components.

Acoustic Stimulation↗

Reducing the risks of alcohol use among urban youth: three-year effects of a computer-based intervention with and without parent involvement.

OBJECTIVE: This study tested a CD-ROM intervention with and without a parent involvement component to reduce risk of alcohol use among an urban sample of early adolescents. METHOD: Youths (N = 514, mean age 11.5 years at recruitment) were assigned randomly by community site to receive the CD-ROM intervention, the CD-ROM plus parent intervention, or no intervention. All youths completed pretest, posttest and three annual follow-up measurements. After pretesting, youths and parents received their respective interventions. RESULTS: Main effects of the intervention and for measurement occasion as well as interaction effects of the intervention by measurement occasion were seen for substance use and related outcomes. Over time, youths in all 3 groups reported increased use of alcohol, tobacco and marijuana; youths who received the interventions reported smaller increases than control youths. At 3-year follow-up, alcohol use was lower for CD-ROM plus parent intervention youths than for CD-ROM only youths, who, in turn, reported less use than controls. Cigarette use was lower for youths in either intervention group than in the control group at posttest and at 1-, 2- and 3-year follow-ups. Marijuana use was lower for youths in either intervention than for controls at 1-, 2- and 3-year follow-ups. Youths in both intervention groups outperformed control youths at posttest and at 1- and 3-year follow-ups on levels of negative and peer influence toward substance use. Finally, at the 3-year follow-up, youths in the CD-ROM plus parent intervention group reported more family involvement in their alcohol use prevention efforts than did youths in the CD-ROM group, who, in turn, reported more positive levels of family involvement than youths in the control group. CONCLUSIONS: Study findings modestly support the CD-ROM intervention with and without the parent intervention to reduce alcohol use risks among urban early adolescents.

Alcohol Drinking↗