Biomedical subjects

Martin D Slade

Publications and source records attributed to Martin D Slade.

16 recordsLinked to original sources

PubMed2006

Anesthesiologists are living longer: mortality experience 1992 to 2001.

STUDY OBJECTIVE: To determine whether there has been any recent change in the mortality experience of American anesthesiologists. DESIGN: Retrospective analysis of obituary reports to the Physician Master File (PMF) of the American Medical Association. MEASUREMENTS: Data were collected from the PMF of anesthesiologists and obstetricians. All data were identified from the PMF. A total of 1525 obituaries of anesthesiologists and 2773 obituaries of obstetricians during the study period, 1992 to 2001, were reviewed. Mean age of living or mean age at death of anesthesiologists and obstetricians, as well as age-adjusted death rates was calculated. MAIN RESULTS: A gradual increase in age at death was noted from 1992 (65.30 +/- 15.61 years) to 2001 (78.13 +/- 12.89 years) for anesthesiologists (P < 0.005). There was a significant linear decrease from 4.3 deaths per thousand to 2.3 deaths per thousand for anesthesiologists in this same period. CONCLUSIONS: We observed a significant increase in the average age at death and a decreased risk of death among anesthesiologists who died in the years 1992 to 2001. Parallel changes were observed in the control population of obstetricians.

Adult↗

PubMed2006

Hearing decline predicted by elders' stereotypes.

Although age-related hearing loss is one of the most prevalent conditions affecting older individuals, little research has been conducted on the social-psychological factors that might contribute to it. The present study examines whether older individuals' age stereotypes predict screened hearing over time. The sample consisted of 546 community-dwelling persons, aged 70 to 96 years old. Participants with more negative and more external (i.e., related to physical appearance) age stereotypes demonstrated worse screened hearing at 36 months, after adjusting for baseline-screened hearing, age, and other relevant variables. These findings suggest that age stereotypes influence older individuals' sensory perception.

Aged↗

PubMed2006

Trends in the prevalence of hearing loss among young adults entering an industrial workforce 1985 to 2004.

OBJECTIVES: Studies have suggested that hearing loss due to recreational noise exposure may be on the rise among adolescents and young adults. This study examines whether the hearing status of young US adults entering an industrial workforce has worsened over the past 20 yr. DESIGN: The baseline audiograms of 2526 individuals ages 17 to 25 beginning employment at a multisite US corporation between 1985 and 2004 were analyzed to determine the yearly prevalence of hearing loss. RESULTS: Approximately 16% of the young adults in the sample had high frequency hearing loss (defined as hearing thresholds greater than 15 dB in either ear at 3,4, or 6 kHz). In a linear regression model, this prevalence decreased over the 20-yr period (odds ratio (OR) = 0.96, 95% confidence interval (CI): 0.94, 0.99). Almost 20% of subjects had audiometric "notches" consistent with noise exposure; this rate remained constant over the 20 yr, as did the prevalence (5%) of low frequency hearing loss. CONCLUSIONS: These results indicate that despite concern about widespread recreational noise exposures, the prevalence of hearing loss among a group of young US adults has not significantly increased over the past two decades.

Adolescent↗

PubMed2006

Audiogram notches in noise-exposed workers.

OBJECTIVES: Diagnostic criteria for noise-induced hearing loss include the audiometric notch, yet no standardized definition exists. This study tested whether objective notch metrics could match the clinical judgments of an expert panel. DESIGN: A panel of occupational physicians, otolaryngologists, and audiologists reviewed audiograms of noise-exposed workers. In a two-sample process, the panel judged whether a notch was present and whether hearing loss had progressed in a notch pattern. Quantitative notch metrics were compared against expert decisions. RESULTS: At least five of six experts agreed about notch identification in 71 and 72% of the cases in the two samples, and agreement about notch progression was 61 and 67%. Notch depth and professional specialty appeared to affect notch judgments. Despite this variability, a notch metric showed excellent agreement with expert notch consensus in each sample (94.7 and 96.6%; kappa = 0.88 and 0.92). CONCLUSIONS: Audiogram notch metrics can agree with expert clinical consensus and assist in the surveillance of noise-exposed workers.

Adult↗

PubMed2006

Incidence of asthma among aluminum workers.

Exposures to respiratory irritants encountered in aluminum smelters in Europe, Australia, and New Zealand have been suggested as the cause of "potroom asthma." However, there remains disagreement in North America regarding the existence of this entity. This study was designed to assess whether asthma occurs excessively among potroom workers and if so, delineate dose-response relationships for possible causal risk factors. The asthma incidence ratio between potroom and nonpotroom workers after adjusting for smoking was 1.40. Although bivariate analyses showed a relationship between asthma incidence and exposure to total fluoride, gaseous fluoride, particulate fluoride, sulfur dioxide, and smoking, only the effects of gaseous fluoride (relative risk [RR] = 5.1) and smoking (RR = 7.7) remained significant in a multivariate model. Potroom asthma appears to occur at the studied U.S. aluminum smelters at doses within regulatory guidelines.

Adult↗

PubMed2006

Use of medical insurance claims data for occupational health research.

OBJECTIVE: The objective of this study was to demonstrate that health claims data, widely available due to the unique nature of the U.S. healthcare system, can be linked to other relevant databases such as personnel files and exposure data maintained by large employers. These data offer great potential for occupational health research. METHODS: In this article, we describe the process for linking claims data to industrial hygiene exposure data and personnel files of a single large employer to conduct epidemiologic research. RESULTS: Our results demonstrate the ability to replicate previously published findings using commonly maintained data sets and illustrate methodological issues that may arise as newer hypotheses are tested in this way. CONCLUSIONS: Health claims files offer potential for epidemiologic research in the United States, although the full extent and guidelines for successful application await further clarification through empiric research.

Adult↗

PubMed2006

Physical recovery after acute myocardial infarction: positive age self-stereotypes as a resource.

We considered whether positive and stable self-stereotypes of stigmatized group members can influence functioning (in contrast, stereotype threat theory suggests these influential self-stereotypes are limited to ones that are negative and situational). Specifically, we examined older individuals' positive age stereotypes after a life-threatening event, an acute myocardial infarction (AMI). Sixty-two persons, aged 50 to 96, participated. As expected, positive age stereotypes were found, even immediately after an AMI, and they did not significantly change over the next seven months. Also as expected, these self-stereotypes predicted physical recovery, after adjusting for potentially relevant covariates. Recovery expectations acted as a mediator. These findings suggest the importance of understanding the role that positive stereotypes may play in the health of stigmatized group members.

Age Factors↗

PubMed2005

Risks of brain tumors in rubber workers: a metaanalysis.

OBJECTIVE: To better understand whether rubber industry workers suffer increased risks of brain tumor, a concern that has persisted for over 40 years despite numerous well-conducted studies. METHODS: We performed a formal metaanalysis of brain tumor risk estimates reported in cohort studies of rubber and tire workers. Twenty unique cohorts were identified who met a priori inclusion criteria. Metaanalysis was performed using the general variance-based method; the variance of risk estimates was calculated for each study using a chi-squared method. Homogeneity was tested by means of the Q statistic. RESULTS: The metaanalysis determined an overall relative risk of 0.90 (95% CI = 0.79-1.02). CONCLUSIONS: The analytical results are consistent with a conclusion that risks of brain tumor are not increased as a result of occupational exposures in the rubber and tire industry.

Brain Neoplasms↗

PubMed2005

Risk factors for tuberculin skin test positivity in an industrial workforce results of a contact investigation.

OBJECTIVE: The objective of this study was to determine the prevalence of and risk factors for tuberculin skin test (TST) positivity among an industrial workforce employing many foreign-born workers after one employee was hospitalized for active tuberculosis (TB). METHODS: A contact investigation was performed. We used crude odds ratios and a multivariate model to assess risk factors for TST positivity. RESULTS: The rate of TST positivity was 37.1% (N=97). Twenty-nine of 36 (80.6%) workers from higher TB prevalence countries versus seven of 61 (11.5%) workers born in low-prevalence countries were positive. Workplace risk factors included using the lunchroom, carpooling with the case, or working on the same or subsequent shift. A total of 66.7% of immigrant workers denied previous screening. CONCLUSION: TB contact investigations should probe into workplace transmission. Workplaces with workers from higher TB prevalence countries should consider pre-placement TB screening.

Adult↗

PubMed2005

Proximity to pollution sources and risk of amphibian limb malformation.

The cause of limb deformities in wild amphibian populations remains unclear, even though the apparent increase in prevalence of this condition may have implications for human health. Few studies have simultaneously assessed the effect of multiple exposures on the risk of limb deformities. In a cross-sectional survey of 5,264 hylid and ranid metamorphs in 42 Vermont wetlands, we assessed independent risk factors for nontraumatic limb malformation. The rate of nontraumatic limb malformation varied by location from 0 to 10.2%. Analysis of a subsample did not demonstrate any evidence of infection with the parasite Ribeiroia. We used geographic information system (GIS) land-use/land-cover data to validate field observations of land use in the proximity of study wetlands. In a multiple logistic regression model that included land use as well as developmental stage, genus, and water-quality measures, proximity to agricultural land use was associated with an increased risk of limb malformation (odds ratio = 2.26; 95% confidence interval, 1.42-3.58; p < 0.001). The overall discriminant power of the statistical model was high (C = 0.79). These findings from one of the largest systematic surveys to date provide support for the role of chemical toxicants in the development of amphibian limb malformation and demonstrate the value of an epidemiologic approach to this problem.

Agriculture↗

PubMed2005

Hearing loss in migrant agricultural workers.

BACKGROUND: Farmers have high rates of hearing loss, yet little is known about the hearing status of migrant agricultural workers. We performed a cross-sectional survey to assess the prevalence and impact of hearing loss in this population. METHODS: One hundred fifty migrant and seasonal agricultural workers were surveyed at a series of health fairs held at migrant camps. A bilingual questionnaire included items related to hearing loss risk factors and subjective hearing difficulties. Pure tone audiometry and tympanometry were performed in a mobile testing van. RESULTS: More than half the subjects had some degree of hearing loss at audiometric frequencies between 500 and 6,000 Hz, especially in the higher frequencies. Hispanic males in the sample had significantly greater prevalence of high-frequency hearing loss compared to adults in the national Hispanic Health and Nutrition Examination Survey (HHANES). More than 35% of respondents complained of subjective difficulty hearing or understanding speech, yet no workers reported use of hearing aids. Even after adjusting for measured hearing loss, Hispanic farm workers were more likely than their English- speaking counterparts to complain of difficulty hearing or understanding speech, suggesting that language barriers could worsen the impact of hearing loss. Risk factors for hearing loss included age and abnormal tympanometry. Occupational exposures to noise from tractors and other machinery as well as pesticides were frequently reported, while use of hearing protection was rare. CONCLUSION: Hearing loss is a significant and under-recognized problem in the migrant worker population. Further preventive and treatment efforts are warranted.

Acoustic Impedance Tests↗

PubMed2004

Vaccination of rabbits with an adenovirus vector expressing the papillomavirus E2 protein leads to clearance of papillomas and infection.

Cervical cancer arises from lesions caused by infection with high-risk types of human papillomavirus (HPV). Therefore, vaccination against HPV could prevent carcinogenesis by preventing HPV infection or inducing lesion regression. HPV E2 protein is an attractive candidate for vaccine development because it is required for papilloma formation, is involved in all stages of the virus life cycle, and is expressed in all premalignant lesions as well as some cancers. This study reports vaccination against E2 protein using a rabbit model of papillomavirus infection. A recombinant adenovirus (Ad) vector expressing the E2 protein of cottontail rabbit papillomavirus (CRPV) was tested for therapeutic efficacy in CRPV-infected rabbits. Primary immunization with the Ad-E2 vaccine, compared to immunization with a control Ad vector, reduced the number of papilloma-forming sites from 17 of 45 to 4 of 45. After booster immunization, vaccinated rabbits formed no new papillomas versus an additional 23 papillomas in rabbits that received the control vector. Papillomas in the Ad-E2 vaccinees were significantly smaller than those in the control rabbits, and all four papillomas in the Ad-E2 vaccinated rabbits regressed. No CRPV DNA was detected either in the regression sites or in sites that did not form papillomas, indicating that the vaccination led to clearance of CRPV from all infected sites.

Adenoviridae↗

PubMed2002

Longevity increased by positive self-perceptions of aging.

This research found that older individuals with more positive self-perceptions of aging, measured up to 23 years earlier, lived 7.5 years longer than those with less positive self-perceptions of aging. This advantage remained after age, gender, socioeconomic status, loneliness, and functional health were included as covariates. It was also found that this effect is partially mediated by will to live. The sample consisted of 660 individuals aged 50 and older who participated in a community-based survey, the Ohio Longitudinal Study of Aging and Retirement (OLSAR). By matching the OLSAR to mortality data recently obtained from the National Death Index, the authors were able to conduct survival analyses. The findings suggest that the self-perceptions of stigmatized groups can influence longevity.

Aged↗

PubMed2002

Longitudinal benefit of positive self-perceptions of aging on functional health.

We examined whether those with more positive self-perceptions of aging (older individuals' beliefs about their own aging) report better functional health over an 18-year period than do those with more negative self-perceptions of aging. We found that those with more positive self-perceptions of aging in 1975 reported better functional health from 1977 to 1995, when we controlled for baseline measures of functional health, self-rated health, age, gender, race, and socioeconomic status. We also demonstrated that perceived control partially mediates the relationship between self-perceptions of aging and functioning. The sample consisted of 433 participants in the Ohio Longitudinal Study of Aging and Retirement, a community-based study of individuals aged 50 and older, who were interviewed in 6 waves. Our study suggests that the way in which individuals view their own aging affects their functional health.

Adult↗

PubMed2002

Ubiquitin-fused and/or multiple early genes from cottontail rabbit papillomavirus as DNA vaccines.

Human papillomavirus (HPV) vaccines have the potential to prevent cervical cancer by preventing HPV infection or treating premalignant disease. We previously showed that DNA vaccination with the cottontail rabbit papillomavirus (CRPV) E6 gene induced partial protection against CRPV challenge and that the vaccine's effects were greatly enhanced by priming with granulocyte-macrophage colony-stimulating factor (GM-CSF). In the present study, two additional strategies for augmenting the clinical efficacy of CRPV E6 vaccination were evaluated. The first was to fuse a ubiquitin monomer to the CRPV E6 protein to enhance antigen processing and presentation through the major histocompatibility complex class I pathway. Rabbits vaccinated with the wild-type E6 gene plus GM-CSF or with the ubiquitin-fused E6 gene formed significantly fewer papillomas than the controls. The papillomas also required a longer time to appear and grew more slowly. Finally, a significant proportion of the papillomas subsequently regressed. The ubiquitin-fused E6 vaccine was significantly more effective than the wild-type E6 vaccine plus GM-CSF priming. The second strategy was to vaccinate with multiple CRPV early genes to increase the breadth of the CRPV-specific response. DNA vaccines encoding the wild-type CRPV E1-E2, E6, or E7 protein were tested alone and in all possible combinations. All vaccines and combinations suppressed papilloma formation, slowed papilloma growth, and stimulated subsequent papilloma regression. Finally, the two strategies were merged and a combination DNA vaccine containing ubiquitin-fused versions of the CRPV E1, E2, and E7 genes was tested. This last vaccine prevented papilloma formation at all challenge sites in all rabbits, demonstrating complete protection.

Animals↗

PubMedDate not supplied

Urinary hexane diamine to assess respiratory exposure to hexamethylene diisocyanate aerosol: a human inhalation study.

The use of urinary hexane diamine (HDA) as a biomarker to assess human respiratory exposure to hexamethylene diisocyanate (HDI) aerosol was evaluated. Twenty-three auto body shop workers were exposed to HDI biuret aerosol for two hours using a closed exposure apparatus. HDI exposures were quantified using both a direct-reading instrument and a treated-filter method. Urine samples collected at baseline, immediately post exposure, and every four to five hours for up to 20 hours were analyzed for HDA using gas chromatography and mass spectrometry. Mean urinary HDA (microg/g creatinine) sharply increased from the baseline value of 0.7 to 18.1 immediately post exposure and decreased rapidly to 4.7, 1.9 and 1.1, respectively, at 4, 9, and 18 hours post exposure. Considerable individual variability was found. Urinary HDA can assess acute respiratory exposure to HDI aerosol, but may have limited use as a biomarker of exposure in the workplace.

Adolescent↗