What influences youth to operate all-terrain vehicles safely?

The operation of all-terrain vehicles (ATVs) by youth has contributed to the incidence of serious and fatal injuries among children. This study explored factors related to the frequency with which youth wore a helmet and refrained from engaging in three risky driving behaviors (driving at risky speeds, on paved roads and on unfamiliar terrain) while operating an ATV. Youth (n = 248) aged 9-14 from central Ohio and one of their parents completed self-report measures of ATV safety behaviors, youth general propensity for risk taking, protection motivation and parental behaviors to facilitate youth safety. Data from two focus groups provided insight on quantitative results. Analyses revealed considerable variation in the frequency with which youth performed the safety behaviors, with 13- and 14-year-olds reporting less frequent safe behavior than 9- to 12-year-olds. Multiple regression analyses suggested that parental behaviors, such as providing reminders to wear a helmet, were associated with more frequent helmet use but were not associated with risky driving behaviors. Youth's general propensity toward risk taking was not associated with helmet use and only associated with riskydriving behaviors among the 13- and 14-year-olds. Self-efficacy was an important predictor across both age groups and behaviors. Implications for injury prevention are discussed.

Comparative performance of contact plates, electrostatic wipes, swabs and a novel sampling device for the detection of Staphylococcus aureus on environmental surfaces.

AIMS: To evaluate the performance of four sampling methods [contact plates, electrostatic wipes (wipe), swabs and a novel roller sampler] for recovery of Staphylococcus aureus from a stainless steel surface. METHODS AND RESULTS: Stainless steel test plates were inoculated with Staph. aureus, dried for 24 h and sampled using each of the four methods. Samples were either incubated directly (roller, contact plate) or processed using elution and membrane filtration (swab, wipe). Performance was assessed by calculating the apparent sampling efficiency (ASE), analytical sensitivity (Sn) and percentage of replications with positive growth. The wipe demonstrated the best performance across all inoculating concentrations (ASE(48 h) = 18%; Sn(48 h) = 7 CFU per 100 cm(2)). The swab performed well when corrected for area actually sampled (ASE(48 h) = 24%; Sn(48 h) = 76 CFU per 100 cm(2)). Of the contact-based methods, the newly developed roller sampler outperformed the contact plate (roller: ASE(48 h) = 10%; Sn(48 h) = 17 CFU per 100 cm(2); contact plate: ASE(48 h) = 0·04%; Sn(48 h) = 1412 CFU per 100 cm(2)); both contact samplers performed better at higher inoculating concentrations (6E3 CFU per 100 cm(2) for the roller and 6E6 CFU per 100 cm(2) for the contact plate). Overall, the electrostatic wipe produced the highest number of replications resulting in positive growth (74%(24 h), 91%(48 h)). CONCLUSIONS: This study demonstrates that selection of the sampling method must be carefully considered, given that different methods have varying performance. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first study assessing static wipes for sampling and one that uses a more real-world-relevant 24-h drying time. The results help with infection control, and environmental health professionals choose better sampling methodologies.

An assessment of depression, anxiety, and stress among nationally certified EMS professionals.

OBJECTIVES: The primary objective of this study was to estimate the prevalence and severity of depression, anxiety, and stress among a cohort of nationally certified emergency medical services (EMS) professionals. The secondary objective was to determine whether there were differences between individuals who were experiencing depression, anxiety, or stress and those who were not. METHODS: This was a questionnaire-based, case-control analysis of nationally certified emergency medical technician (EMT)-Basics and paramedics who applied for national recertification in 2009. The three outcome variables of interest included measures of depression, anxiety, and stress, and were assessed using the Depression Anxiety Stress Scale-21 (DASS-21). Descriptive statistics and investigator-controlled backwards-selection logistic regression modeling were utilized to quantify the prevalence of depression, anxiety, and stress and to predict the association of demographic and work-life characteristics with each outcome. RESULTS: A total of 64,032 individuals were eligible to renew their national certification and 34,340 (53.6%) individuals returned a questionnaire. The DASS-21 classified 1,589 (6.8%, 95% confidence interval [CI] = 6.4%-7.1%) EMS professionals as depressed, 1,406 (6.0%, 95% CI = 5.7%-6.3%) as anxious, and 1,382 (5.9%, 95% CI = 5.6%-6.2%) as stressed. Multivariable logistic regression estimates showed that paramedics (odds ratio [OR] = 1.31, 95% CI = 1.22-1.39), those working in county or municipal services (OR = 1.36, 95% CI = 1.16-1.60) or private services (OR = 1.32, 95% CI = 1.14-1.52), and those with ≥16 years of EMS experience (OR = 1.28, 95% CI = 1.01-1.62) had an increased odds of depression. A stepwise increase was found when estimating the effects of self-reported general health on the odds of anxiety (very good, OR = 1.84, 95% CI = 1.53-2.22; good, OR = 3.88, 95% CI = 3.32-4.67; fair/poor, OR = 10.81, 95% CI = 8.14-14.34). Likewise, paramedics (OR = 1.32, 95% CI = 1.23-1.42), those working in a private EMS system (OR = 1.35, 95% CI = 1.16-1.56), and those with ≥16 years of EMS experience (OR = 1.67, 95% CI = 1.28-2.18) had an increased odds of stress. CONCLUSIONS: This study was able to estimate the prevalence of depression, anxiety, and stress among a large cohort of nationally certified EMS professionals and identified statistically significant demographic and work-life characteristics that predicted depression, anxiety, and stress. Future research should attempt to follow EMS professionals prospectively to determine specific characteristics associated with occupational traumatic exposure and the development of depression, anxiety, and stress.

Complaints associated with animal feeding facilities as reported to Ohio local health departments, 2006-2008.

Confined animal feeding facilities of all sizes have long been targeted as a source of human health and quality of life concerns. In order to describe and quantify these concerns in Ohio, a retrospective survey of local health departments was conducted focusing on reported complaints associated with animal feeding facilities. During 2006-2008, the most common complaints pertaining to any type of animal feeding facility were air quality and odor outside the home, followed by manure storage and application issues. The study described here showed that larger permitted livestock feeding facilities were not a major source of health and nuisance complaints associated with animal feeding facilities as reported to Ohio local health departments. Local health departments received few health complaints associated with any animal feeding facility. None were validated or confirmed by a physician in 2008.

In vivo phycocyanin flourometry as a potential rapid screening tool for predicting elevated microcystin concentrations at eutrophic lakes.

Current approaches for assessing human health risks associated with cyanotoxins often rely on the quantification of microcystin. Significant limitations of current approaches are cost and time to obtain a result. To address these challenges, a numerical index for screening microcystin risks above the World Health Organization's (WHO) low-risk threshold for microcystin was developed for eutrophic Midwestern U.S. lakes based on water quality results from 182 beach water samples collected from seven Ohio lakes. In 48 (26.4%) samples we observed microcystin concentrations as measured by ELISA that exceeded the 4 µg/L microcystin threshold. A multivariable logistic regression model using practical real-time measures of in vivo phycocyanin (by fluorometry) and secchi depth was constructed to estimate the probability of a beach sample exceeding 4 µg/L microcystin. The final model achieved statistical significance (p = 0.030) as well as good calibration (as measured by the goodness-of-fit test comparing observed to expected counts within deciles of risk based on the model, p = 0.329) and discrimination (as indicated by the area under the receiver-operator-curve (0.795)). These results demonstrate two rapid and practical measures of recreational water quality are effective in identifying "at risk" lake conditions warranting additional management (e.g., advisory and/or advanced testing).

Medical expenditures associated with nonfatal occupational injuries among immigrant and U.S.-born workers.

BACKGROUND: No national study has investigated whether immigrant workers are less likely than U.S.-workers to seek medical treatment after occupational injuries and whether the payment source differs between two groups. METHODS: Using the 2004-2009 Medical Expenditure Panel Survey (MEPS) data, we estimated the annual incidence rate of nonfatal occupational injuries per 100 workers. Logistic regression models were fitted to test whether injured immigrant workers were less likely than U.S.-born workers to seek professional medical treatment after occupational injuries. We also estimated the average mean medical expenditures per injured worker during the 2 year MEPS reference period using linear regression analysis, adjusting for gender, age, race, marital status, education, poverty level, and insurance. Types of service and sources of payment were compared between U.S.-born and immigrant workers. RESULTS: A total of 1,909 injured U.S.-born workers reported 2,176 occupational injury events and 508 injured immigrant workers reported 560 occupational injury events. The annual nonfatal incidence rate per 100 workers was 4.0% (95% CI: 3.8%-4.3%) for U.S.-born workers and 3.0% (95% CI: 2.6%-3.3%) for immigrant workers. Medical treatment was sought after 77.3% (95% CI: 75.1%-79.4%) of the occupational injuries suffered by U.S.-born workers and 75.6% (95% CI: 69.8%-80.7%) of the occupational injuries suffered by immigrant workers. The average medical expenditure per injured worker in the 2 year MEPS reference period was $2357 for the U.S.-born workers and $2,351 for immigrant workers (in 2009 U.S. dollars, P = 0.99). Workers' compensation paid 57.0% (95% CI: 49.4%-63.6%) of the total expenditures for U.S.-born workers and 43.2% (95% CI: 33.0%-53.7%) for immigrant workers. U.S.-born workers paid 6.7% (95% CI: 5.5%-8.3%) and immigrant workers paid 7.1% (95% CI: 5.2%-9.6%) out-of-pocket. CONCLUSIONS: Immigrant workers had a statistically significant lower incidence rate of nonfatal occupational injuries than U.S.-born workers. There was no significant difference in seeking medical treatment and in the mean expenditures per injured worker between the two groups. The proportion of total expenditures paid by workers' compensation was smaller (marginally significant) for immigrant workers than for U.S.-born workers.

Using protection motivation theory and formative research to guide an injury prevention intervention: increasing adherence to the North American Guidelines for Children's Agricultural Tasks.

The North American Guidelines for Children's Agricultural Tasks (NAGCAT) were developed to reduce childhood agricultural injuries by assisting adults in assigning appropriate chores and providing needed supervision and training. To develop an effective intervention to increase adherence to NAGCAT among farm parents, formative research (focus groups and pilot-testing) was conducted. Protection motivation theory (PMT) was used to guide this research and inform intervention development. Focus group results suggested how PMT constructs might be addressed to increase adherence. A home visit intervention, using a standardized presentation in POWERPoint™, was developed to (a) introduce NAGCAT, (b) increase motivation to use NAGCAT and enhance safe work behaviors, and (c) ultimately reduce agricultural work-related injuries among youth. Process evaluation data suggests that the intervention was well received by farm parents. Conducting theory-guided formative research identified motivational barriers and strategies for overcoming these barriers that might not have been otherwise apparent.

Low cancer incidence rates in Ohio Amish.

BACKGROUND: The Amish have not been previously studied for cancer incidence, yet they have the potential to help in the understanding of its environmental and genetic contributions. The purpose of this study was to estimate the incidence of cancer among the largest Amish population. METHODS: Adults from randomly selected households were interviewed and a detailed cancer family history was taken. Using both the household interview data and a search of the Ohio cancer registry data, a total of 191 cancer cases were identified between the years 1996 and 2003. RESULTS: The age-adjusted cancer incidence rate for all cancers among the Amish adults was 60% of the age-adjusted adult rate in Ohio (389.5/10(5) vs. 646.9/10(5); p < 0.0001). The incidence rate for tobacco-related cancers in the Amish was 37% of the rate for Ohio adults (p < 0.0001). The incidence rate for non-tobacco-related cancers in the Amish was 72% of the age-adjusted adult rate in Ohio (p = 0.0001). CONCLUSION: Cancer incidence is low in the Ohio Amish. These data strongly support reduction of cancer incidence by tobacco abstinence but cannot be explained solely on this basis. Understanding these contributions may help to identify additional important factors to target to reduce cancer among the non-Amish.

Disability and employment among U.S. working-age immigrants.

BACKGROUND: There is little research which examines disability status and the employment decisions of the US immigrant working-age population. METHODS: The 2007 American Community Survey data were analyzed to compare disabilities and employment characteristics between immigrant and US-born adults 18-64 years of age. Separate logistic regression models of employment were constructed among persons with disabilities and among persons without disabilities. Each multivariate model included nativity/citizenship, sex, race/ethnicity, age, and education. RESULTS: In 2007, 40.8% (95% CI: 39.9-41.7) of immigrants with disabilities were employed, while only 34.9% (95% CI: 34.6-35.2) of US-born persons with disabilities were employed. For each type of disability, including difficulty working, immigrants with disabilities were more likely than their US-born counterparts to be employed. The median wage/salary incomes for persons with disabilities, foreign-born and US-born, respectively, were $20,000 and $22,000. In contrast, the median wage/salary incomes of foreign-born persons with mental impairments, self-care limitations, or participation restrictions exceeded those of US-born persons with these same disabilities. Nativity and citizenship had different effects in separate logistic models of employment for persons with disabilities and persons without disabilities. Among persons with disabilities, foreign-born citizens were more likely to be employed than the US-born, OR = 1.40 (95% CI: 1.33-1.48), and non-citizens were also more likely to be employed, OR = 1.74 (95% CI: 1.62-1.87), than US-born persons. Among persons without disabilities, foreign-born non-citizens were less likely to be employed than the US-born, OR = 0.82 (95% CI: 0.82-0.85). CONCLUSION: Immigrants with disabilities were more frequently employed than US-born persons with disabilities for all types of disabilities.

Hearing problems among a cohort of nationally certified EMS professionals.

PURPOSE: The objectives of this study were to estimate the prevalence of hearing problems among a national cohort of emergency medical service (EMS) professionals, determine factors associated with hearing problems, and estimate the percentage of EMS professionals who utilize hearing protection. METHODS: Utilizing results from a questionnaire, individuals who reported hearing problems were compared to individuals who had not. Multivariable logistic regression was performed to identify variables associated with hearing problems. Finally, items regarding use of hearing protection were assessed to estimate the percentage of usage among EMS professionals. RESULTS: In total, 1,058 (57%) participants responded to the questionnaire. Of those, 1,024 (97%) who completed the hearing problems question were utilized for analysis. There were 153 (14.9%) cases of self-reported hearing problems. The final logistic regression model included lifetime occupational noise exposure 0.99 (95% CI = 0.9997-1.0002), report of previous back problems (odds ratio (OR) = 2.74, 95% CI = 1.8340-4.1042), large community size (OR = 1.67, 95% CI = 1.1211-2.4843), and minority status (OR = 0.61, 95% CI = 0.3719-0.9867). Finally, 213 (20.8%) individuals reported utilizing some form of hearing protection at their main EMS job. CONCLUSION: The results from this analysis are the first national estimates of the prevalence of self reported hearing problems among EMS professionals. This study was also the first to estimate the percentage of EMS professionals who self reported the utilization of hearing protection.

Back problems among emergency medical services professionals: the LEADS health and wellness follow-up study.

OBJECTIVE: Describe work-life and demographic characteristics associated with reporting recent back pain, and estimate back pain severity among Emergency Medical Services (EMS) professionals. METHODS: A 58-item postal questionnaire was used to collect relevant health and wellness information from a national sample of EMS professionals. The outcome variables were self-reported pain in the back or legs, and severity of recent back pain as indicated by the Aberdeen Back Pain Scale (ABPS). RESULTS: There were 470/930 (50.5%) participants who reported one or more days of pain in the back or legs over a 2-week period. The variables most strongly associated with recent back pain and pain severity were prior back problems, self-reported health, and job satisfaction. CONCLUSION: This study indicated that work-life, health, and demographic characteristics of EMS professionals were associated with reporting recent back pain.

Hearing loss among Ohio farm youth: a comparison to a national sample.

BACKGROUND: Hearing loss is prevalent among adults in the farming community, with some evidence it begins in childhood. Our objective was to compare hearing thresholds of Ohio farm youth to published data on national norms. METHODS: Baseline data were collected on youth (n = 212) in 1994-1996 with follow-up (n = 132) in 2003-2004 including pure-tone air conduction thresholds at 0.5, 1, 2, 3, 4, 6, and 8 kHz. RESULTS: When compared to nationally-representative data, study youth had a higher prevalence of hearing loss. The high-frequency range was most affected, particularly at 6 kHz where nearly 50% of the farm youth exhibited some degree of hearing loss at baseline testing. The prevalence of noise-induced threshold shifts, characterized by an audiometric notch, was nearly twice that of the national sample. CONCLUSIONS: These data suggest that hearing loss, which is common among adult farmers, may be problematic for farm youth as well.

Affinity-labeled plasma somatomedin-C/insulinlike growth factor I binding proteins. Evidence of growth hormone dependence and subunit structure.

By using disuccinimidyl suberate, we have covalently cross-linked 125I-labeled somatomedin-C (Sm-C)/insulinlike growth factor I to specific binding proteins in human plasma. In unfractionated plasma samples from normal and acromegalic donors, 125I-Sm-C binding-protein complexes with relative molecular weights (Mr) of 160,000, 135,000, 110,000, 80,000, 50,000, 43,000-35,000, and 28,000-24,000 were consistently observed. In contrast, the 43,000-35,000-mol wt species were frequently the only specific complexes observed in hypopituitary plasma and were consistently more intensely labeled in such samples. Reduction of samples with beta-mercaptoethanol did not alter the electrophoretic pattern of these 125I-Sm-C binding-protein complexes. All Sm-C binding proteins, with the exception of the 43,000-35,000-mol wt complex, were adsorbed by concanavalin A-Sepharose. When acromegalic or normal plasma was fractionated on a Sephadex G-200 column and affinity labeled, the same complexes that were adsorbed by concanavalin A were found in fractions that eluted near the gamma-globulin peak. On the other hand, the 43,000-35,000-mol wt complex consistently eluted in size-appropriate fractions near the albumin peak. These data suggest that the growth hormone (GH)-dependent Sm-C binding protein, represented by the 160,000-mol wt complex, is in some way composed of smaller species, i.e., the 135,000-, 110,000-, 80,000-, 50,000-, and 28,000-24,000-mol wt complexes. Acid incubation of plasma prior to Sephadex G-200 chromatography results in the elimination of specific 125I-Sm-C binding-protein complexes which elute near gamma-globulin and a concurrent increase in the labeling intensity of the 28,000-24,000-mol wt complexes. We speculate, therefore, that each of the GH-dependent Sm-C binding-protein complexes represents an oligomer composed of 28,000-24,000-mol wt protomers. The 43,000-35,000-mol wt species is not dependent upon GH and appears to represent a different type of Sm-C binding protein.

Using participant event monitoring in a cohort study of unintentional injuries among children and adolescents.

OBJECTIVES: We conducted a 3-year cohort study of 407 youths aged 9 to 18 years to develop multivariable risk prediction models of agriculture-related injuries. METHODS: Data were obtained via participant event monitoring, with youths self-reporting injuries and exposures in daily diaries over a 13-week period. We evaluated data quality by comparing injury self-reports with other injury data. RESULTS: Semilogarithmic plots of rates of all unintentional injuries combined (US data from 2000) as well as of agriculture-related injuries (US and Canadian data from 19 previous studies) graphed as a function of injury severity exhibited linearity, as did plots based on the present results. Severity-specific unintentional injury rates were 1.4- to 4.3-times higher than national rates, suggesting that our methodology can significantly reduce injury underreporting. In addition, at each severity level, estimated agriculture-related injury rates were 5.8- to 9.3-times higher than rates from previous national, regional, and state-based studies. CONCLUSIONS: Our approach to participant event monitoring can be implemented with youths aged 9 to 18 years and will yield reliable daily data on unintentional injuries.

Risk of vehicle-pedestrian and vehicle-bicyclist collisions among children with disabilities.

OBJECTIVES: To examine the potential association between disability and risk of vehicle-pedestrian and vehicle-bicyclist collisions among children. METHODS: Data from the 2002 National Transportation Availability and Use Survey for Persons with Disabilities (NTAUSPD) were analyzed. RESULTS: Among 5019 persons who completed the survey, there were a total of 687 children between 5-17 years of age, including 299 respondents with and 388 without disabilities. After controlling for potential confounding variables, children with disabilities were more than five times more likely to have been hit by a motor vehicle as a pedestrian or bicyclist than children without disabilities (adjusted OR = 5.53, 95% confidence interval (CI): 1.43-21.41). For all children, regardless of their disability status, children who reported having some difficulty with traffic had a significantly higher risk of collisions (adjusted OR = 50.71, 95% CI: 7.35-349.86). The most commonly reported traffic difficulties for all children with and without disabilities were "Too few or missing sidewalks/paths," "Do not know when it's safe to cross," and "Insensitive/unaware drivers." CONCLUSIONS: Existing effective transportation safety interventions should be effective in reducing the risk of vehicle-pedestrian and vehicle-bicyclist collisions in children with disabilities. Future research and safety interventions should focus on how to promote the use of existing effective transportation safety interventions among children with disabilities and their families.

Time-dependent recordkeeping fatigue among youth completing health diaries of unintentional injuries.

PROBLEM: Increasingly, investigators are asking youth to self-report daily activity patterns and health outcomes in diary studies. This study assesses recordkeeping fatigue with respect to data quality and event reporting among youth participating in a health diary study. METHOD: Unintentional injury data were collected during a 13-week longitudinal diary study of Ohio youth exposed to agricultural hazards. Two analyses were conducted using data from 2000. Analysis 1 examined trends in discernable recordkeeping errors (DREs) over the course of follow-up. Analysis 2 assessed trends in injury reporting over follow-up. RESULTS: The percentage of items containing a DRE showed a slight, non-significant decline throughout follow-up. Injury reporting declined significantly (p<0.001) over follow-up. SUMMARY: There was no compelling evidence of respondent fatigue with respect to DREs. The observed decline in injury reporting is problematic because estimates of youth injury incidence in health diary studies may vary depending upon the length of the follow-up period.

Effects of simultaneous prenatal exposures to organophosphate and synthetic pyrethroid insecticides on infant neurodevelopment at three months of age.

Both prenatal organophosphate (OP) and pyrethroid (PYRE) insecticide exposures have been inconsistently linked with poorer neurodevelopmental outcomes. However, given that neither exposure occurs in isolation, and both classes are neurotoxic, it is important to consider both classes when evaluating these outcomes. Employing biomarkers of pesticide exposure, this research describes the effects of prenatal urinary metabolite levels of PYRE and OP insecticides, measured in both the second and third trimesters of pregnancy and postnatal urinary metabolite levels measured at 2 months of age, on child neurodevelopment at three months of age. Neurodevelopmental data were obtained by administration of the Bayley Scales of Infant Development-II (BSID-II). Generalized linear models using maximum likelihood estimation were used to evaluate the relationship between the indicators of motor and mental neurobehavioral development obtained for 118 infants and prenatal insecticide exposure, accounting for the concurrent infant insecticide exposure. Urinary measures of the PYRE metabolites 3-phenoxybenzoic acid (3PBA) and trans-3-(2,2-dichlorovinyl)-2,2 dimethylcyclopropane-1-carboxylic acid (trans-DCCA) in the third trimester of pregnancy had significant, albeit opposite, effects on mental functioning at three months of age. We observed no significant (p < 0.05) effects on motor development. These results were robust to second month infant urine measures of 3,5,6-trichloro-2-pyridinol (metabolite of OP chlorpyrifos), which independently had a significant and negative influence on mental functioning. Prenatal PYRE exposures exert heterogeneous effects by class on mental, but not motor, functioning at three months of age.

Obesity and risk of nonfatal unintentional injuries.

BACKGROUND: Obesity is recognized as a risk factor for multiple chronic diseases. Yet, it is unclear whether obesity is also associated with an increased risk of nonfatal unintentional injury. METHODS: A population-based survey was conducted among adults aged > or = 18 years from January 1999 through October 2000. The relationship was investigated between body mass index (BMI), defined as weight in kilograms divided by the square of the height in meters (kg/m2), and risk of nonfatal unintentional injuries among 2575 respondents aged > or = 20 years by comparing percentage of adults between obese and nonobese respondents who had injuries. Multivariate logistic regression further examined this relationship by controlling for confounding demographics. RESULTS: A total of 370 respondents reported injuries in the previous year. We observed a linear dose-response trend among women. An estimated 7.0% of underweight individuals (BMI <18.5) reported injuries. In contrast, 26.0% of men and 21.7% of women with a BMI > or = 35.0 reported injuries. The odds ratio of injuries for individuals with a BMI > or = 35.0 was 2.00 (95% confidence interval=1.07-3.74, p<0.05) after controlling for gender, age, education level, marital status, family poverty status, and area of residence. CONCLUSIONS: A marginally significant association between extreme obesity and elevated risk of injuries was observed. Efforts to promote optimal body weight may reduce not only the risk of chronic diseases but also the risk of unintentional injury among overweight and obese individuals.

Short- and long-term effects of ambient ozone and fine particulate matter on the respiratory health of chronic obstructive pulmonary disease subjects.

To date, no study has evaluated the short- and long-term effects air pollution exposure on emphysematous subjects who have undergone lung volume reduction surgery (LVRS). Data from the National Emphysema Treatment Trial study (1998-2003) included 1,218 subjects, aged 39 to 84. Daily values of ambient fine particulate matter (aerodynamic diameter < 2.5 µm; PM2.5) and ozone were obtained. Mixed-effects models tested the association between short- and long-term pollutant concentrations and changes in pulmonary function. Cumulative air pollution exposure was strongly associated with worsened respiratory function and symptoms. Mean PM2.5 was associated with poorer lung function. Lagged exposures were poorly associated with respiratory health outcomes. There were detrimental respiratory and pulmonary effects observed in response to even low levels of ambient air pollutants among study participants. These results are indicative that exposures even below those of air quality standards may still pose significant risks to severe chronic obstructive pulmonary disease (COPD) subjects.

Affinity labeled somatomedin-C-binding proteins in rat sera.

We have developed an affinity labeling technique that uses disuccinimidyl suberate to covalently cross-link [125I]somatomedin-C (Sm-C) to specific binding proteins in rat serum. Normal rat serum contains four major classes of intensely labeled [125I]Sm-C-binding protein complexes which are sensitive to competition with unlabeled Sm-C with relative molecular masses of 95, 49, 36-33, and 26-23 K. In addition, less intensely labeled complexes are observed migrating between 175 and 115 K. Of the Sm-C binding complexes observed in normal serum, hypophysectomized (hypox) serum contains only an intensely labeled 36-33-K complex and a faint 49-K complex. Chronic administration of ovine (100 micrograms, ip, daily) to hypox rats induces the 95-K complex and possibly complexes between 175-115 K. With increasing duration of treatment, these complexes as well as the 49-K complex appear to increase in intensity. Binding proteins in both hypox and normal sera do not appear to distinguish between Sms, since both unlabeled Sm-C and multiplication-stimulating activity were equally potent in competing with [125I]Sm-C for binding. This affinity labeling technique appears to be a useful investigative tool to study the physiology and structure of Sm-binding proteins.