Heather G. Stockwell
University of South Florida
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Heather G. Stockwell.
Work & Stress | 2007
Paul E. Spector; Martha L. Coulter; Heather G. Stockwell; Mary Matz
Abstract Workplace accidents and violence are both potential sources of employee injuries that have been dealt with in entirely separate literatures. In this study we adapted the concept of safety climate from the accident/injury literature to violence in developing the concept of perceived violence climate. A scale was developed to assess perceived violence climate, including items about management attention, concern, and policies designed to keep employees safe from violence. Data were collected from a sample of 198 nurses from a US Hospital. Perceived violence climate was found to correlate significantly with both physical violence and verbal aggression experienced by the nurses, injury from violence, and perceptions of workplace danger. Furthermore, regression analyses showed that climate explained additional variance in psychological strain and perceptions of danger over experienced violence. These results have implications for interventions aimed at producing a good perceived violence climate in order to reduce the incidence of violence and aggression within an organization.
Journal of Neurosurgery | 2008
Jill S. Barnholtz-Sloan; Vonetta L. Williams; John L. Maldonado; Dilip Shahani; Heather G. Stockwell; Marc C. Chamberlain; Andrew E. Sloan
OBJECT This study was undertaken to evaluate the association between age at diagnosis, patterns of care, and outcome among elderly individuals with anaplastic astrocytoma (AA) and glioblastoma multiforme (GBM). Methods Using the Surveillance, Epidemiology and End Results database, the authors identified 1753 individuals with primary GBM and 205 individuals with primary AA (diagnosed between June 1991 and December 1999) who were 66 years and older and whose records were linked to Medicare information. To facilitate gathering of prediagnosis comorbidity and postdiagnosis treatment information, only those individuals were included who had the same Medicare coverage for 6 months before and 12 months after diagnosis. The odds of undergoing various combinations of treatments and the associations with outcome were calculated by tumor type and age and adjusted by various predictors. RESULTS Age was not associated with treatment differences in individuals with AA. Very elderly individuals (>or= 75 years old) with GBM were more likely to have biopsy only (odds ratio [OR] 2.53, 95% confidence interval [CI] 1.78-3.59), surgery only (OR 1.47, 95% CI 1.15-1.87), or biopsy and radiation (OR 1.39, 95% CI 1.07-1.82) and were less likely to receive multimodal therapy. Regardless of patient age or lesion histological characteristics, survival was decreased in patients treated with biopsy only. Individuals with GBM who had surgery only or biopsy and radiation had worse outcomes than individuals treated with surgery and radiation. There were no differences in survival by lesion histological characteristics. Very elderly individuals with malignant astrocytomas were more likely to receive limited treatment (most pronounced in individuals with GBM). Survival variation correlated with treatment combinations. CONCLUSIONS These findings suggest that in clinical neurooncology patient age is associated with not receiving effective therapies and hence worse prognosis.
American Journal of Obstetrics and Gynecology | 1987
Heather G. Stockwell; Gary H. Lyman
An epidemiologic study was conducted to evaluate the relationship between cigarette smoking and the risk of breast, endometrial, and ovarian cancers. Results indicated a clear reduction of risk for endometrial cancer among women aged 50 years and older who smoke cigarettes. Risks were significantly reduced among moderate smokers (odds ratio = 0.6), heavy smokers (odds ratio = 0.4), and former smokers (odds ratio = 0.6). No association was observed among women under age 50 years. When the relationship between cigarette smoking and breast cancer was investigated, no statistically significant association between cigarette smoking and the risk of breast cancer was observed except among women >50 years who were light smokers only. There was also a nonstatisticallysignificant increase in risk among younger women smoking more than two packs of cigarettes a day (odds ratio = 2.0), but overall there was no evidence of any relationship. Similarly, no association between ovarian cancer and cigarette smoking was apparent, although there was a nonsignificant increase in risk among women under age 50 years who smoked 40 or more cigarettes a day or were exsmokers.
Nutrition and Cancer | 1992
Elizabeth C. Candelora; Heather G. Stockwell; Adam W. Armstrong; Patricia A. Pinkham
A case-control study was conducted to examine the influence of dietary factors on the risk of developing lung cancer among women who have never smoked cigarettes. This study included 124 cases of histologically confirmed carcinoma of the lung and 263 community-based controls. Dietary data were collected utilizing the reduced version of the National Cancer Institute (Block) food frequency questionnaire. The results of this analysis, adjusted for age, education, and total calories, indicated a strong protective effect associated with total vegetable consumption and intake of carotene. Individuals in the highest quartile of vegetable consumption experienced the greatest decreased risk with an odds ratio (OR) of 0.2, [confidence interval (CI) 0.1-0.5]. The effect of all vegetables combined was greater than that of green and yellow vegetables alone (highest quartile OR 0.4, CI 0.2-0.7). Similarly, the protective effect of total carotene (highest quartile OR 0.3, CI 0.1-0.6) was somewhat greater than that of beta-carotene alone (highest quartile OR 0.4, CI 0.2-0.8). Retinol intake was not associated with a decreased risk of lung cancer in our population. There was an inverse association between lung cancer risk and vitamin C intake, which was not significant, although a statistically significant trend was noted.
Cancer Research | 2011
Jennifer Permuth-Wey; Donghwa Kim; Ya Yu Tsai; Hui-Yi Lin; Y. Ann Chen; Jill S. Barnholtz-Sloan; Michael J. Birrer; Gregory C. Bloom; Stephen J. Chanock; Zhihua Chen; Daniel W. Cramer; Julie M. Cunningham; Getachew A. Dagne; Judith Ebbert-Syfrett; David Fenstermacher; Brooke L. Fridley; Montserrat Garcia-Closas; Simon A. Gayther; William Ge; Aleksandra Gentry-Maharaj; Jesus Gonzalez-Bosquet; Ellen L. Goode; Edwin S. Iversen; Heather Jim; William Kong; John R. McLaughlin; Usha Menon; Alvaro N.A. Monteiro; Steven A. Narod; Paul Pharoah
Defective microRNA (miRNA) biogenesis contributes to the development and progression of epithelial ovarian cancer (EOC). In this study, we examined the hypothesis that single nucleotide polymorphisms (SNP) in miRNA biogenesis genes may influence EOC risk. In an initial investigation, 318 SNPs in 18 genes were evaluated among 1,815 EOC cases and 1,900 controls, followed up by a replicative joint meta-analysis of data from an additional 2,172 cases and 3,052 controls. Of 23 SNPs from 9 genes associated with risk (empirical P < 0.05) in the initial investigation, the meta-analysis replicated 6 SNPs from the DROSHA, FMR1, LIN28, and LIN28B genes, including rs12194974 (G>A), an SNP in a putative transcription factor binding site in the LIN28B promoter region (summary OR = 0.90, 95% CI: 0.82-0.98; P = 0.015) which has been recently implicated in age of menarche and other phenotypes. Consistent with reports that LIN28B overexpression in EOC contributes to tumorigenesis by repressing tumor suppressor let-7 expression, we provide data from luciferase reporter assays and quantitative RT-PCR to suggest that the inverse association among rs12194974 A allele carriers may be because of reduced LIN28B expression. Our findings suggest that variants in LIN28B and possibly other miRNA biogenesis genes may influence EOC susceptibility.
Cancer Epidemiology, Biomarkers & Prevention | 2011
Beibei Lu; Raphael P. Viscidi; Ji-Hyun Lee; Yougui Wu; Luisa L. Villa; Eduardo Lazcano-Ponce; Roberto J. Carvalho da Silva; Maria Luiza Baggio; Manuel Quiterio; Jorge Salmerón; Danelle Smith; Martha Abrahamsen; Mary Papenfuss; Heather G. Stockwell; Anna R. Giuliano
Background: Few human papillomavirus (HPV) serology studies have evaluated type-specific seroprevalence of vaccine HPV types in men. This study investigates seroprevalence of HPV 6, 11, 16, and 18, and associated risk factors in men residing in three countries (United States, Mexico, and Brazil). Methods: Data from 1,477 men aged 18 to 70 enrolled in the HPV Infection in Men Study (HIM Study) were analyzed. Serum antibody testing was performed with virus-like particle-based ELISA. Potential risk factors were assessed for individual HPV types by the use of logistic regression. Results: Overall, HPV-6, 11, 16, and 18 seroprevalence was 14.8%, 17.3%, 11.2%, and 5.8%, respectively. Thirty-four percent of men were seropositive to one or more HPV types. When examined by sexual practice, 31.2% of men who had sex with women, 65.6% of men who had sex with men (MSM), and 59.4% of men who had sex with both men and women (MSMW) were seropositive to one or more HPV types. Seroprevalence increased with age among young-to-middle-aged men with significant upward age trends observed for HPV 11, 16, and 18. Men with multiple lifetime male anal sex partners were 2 to 4 times more likely to be HPV 6 or 11 seropositive and 3 to 11 times more likely to be HPV 16 or 18 seropositive. Conclusion: Our data indicate that exposures to vaccine HPV types were common in men and highly prevalent among MSM and MSMW. Impact: Our study provides strong evidence that the practice of same-sex anal intercourse is an independent risk factor for seroprevalence of individual vaccine HPV types. Examination of antibody responses to HPV infections at various anatomic sites in future studies is needed to elaborate on the mechanism. Cancer Epidemiol Biomarkers Prev; 20(5); 990–1002. ©2011 AACR.
Cancer Research | 2012
Beibei Lu; Raphael P. Viscidi; Yougui Wu; Ji-Hyun Lee; Alan G. Nyitray; Luisa L. Villa; Eduardo Lazcano-Ponce; Roberto J. Carvalho da Silva; Maria Luiza Baggio; Manuel Quiterio; Jorge Salmerón; Danelle Smith; Martha Abrahamsen; Mary Papenfuss; Heather G. Stockwell; Anna R. Giuliano
In women, naturally induced anti-human papilloma virus (HPV) serum antibodies are a likely marker of host immune protection against subsequent HPV acquisition and progression to precancerous lesions and cancers. However, it is unclear whether the same is the case in men. In this study, we assessed the risk of incident genital infection and 6-month persistent genital infection with HPV16 in relation to baseline serostatus in a cohort of 2,187 men over a 48-month period. Genital swabs were collected every 6 months and tested for HPV presence. Incidence proportions by serostatus were calculated at each study visit to examine whether potential immune protection attenuated over time. Overall, incidence proportions did not differ statistically between baseline seropositive and seronegative men at any study visit or over the follow-up period. The risk of incident and 6-month persistent infection was not associated with baseline serostatus or baseline serum antibody levels in the cohort. Our findings suggest that baseline HPV seropositivity in men is not associated with reduced risk of subsequent HPV16 acquisition. Thus, prevalent serum antibodies induced by prior infection may not be a suitable marker for subsequent immune protection against genital HPV16 acquisition in men.
The Journal of Infectious Diseases | 2011
Gabriella M. Anic; Ji-Hyun Lee; Heather G. Stockwell; Dana E. Rollison; Yougui Wu; Mary Papenfuss; Luisa L. Villa; Eduardo Lazcano-Ponce; Christine Gage; Roberto J. Carvalho da Silva; Maria Luiza Baggio; Manuel Quiterio; Jorge Salmerón; Martha Abrahamsen; Anna R. Giuliano
BACKGROUND Data on the natural history of human papillomavirus (HPV)-related genital warts (GWs) in men are sparse. We described the distribution of HPV types in incident GWs and estimated GW incidence and time from type-specific incident HPV infections to GW detection in a multinational cohort of men aged 18-70 years. METHODS Participants included 2487 men examined for GWs and tested for HPV every 6 months and followed up for a median of 17.9 months. Samples were taken from 112 men with incident GWs to test for HPV DNA by polymerase chain reaction. RESULTS Incidence of GWs was 2.35 cases per 1000 person-years, with highest incidence among men aged 18-30 years (3.43 cases per 1000 person-years). HPV 6 (43.8%), HPV 11 (10.7%), and HPV 16 (9.8%) were the genotypes most commonly detected in GWs. The 24-month cumulative incidence of GWs among men with incident HPV 6/11 infections was 14.6% (95% confidence interval [CI], 7.5%-21.1%). Median time to GW detection was 17.1 months (95% CI, 12.4-19.3 months), with shortest time to detection among men with incident infections with HPV 6/11 only (6.2 months; 95% CI, 5.6-24.2 months). CONCLUSIONS HPV 6/11 plays an important role in GW development, with the highest incidence and shortest time to detection among men with incident HPV 6/11 infection.
Cancer Epidemiology, Biomarkers & Prevention | 2011
Jennifer Permuth-Wey; Y. Ann Chen; Ya Yu Tsai; Zhihua Chen; Xiaotao Qu; Johnathan M. Lancaster; Heather G. Stockwell; Getachew A. Dagne; Edwin S. Iversen; Harvey A. Risch; Jill S. Barnholtz-Sloan; Julie M. Cunningham; Robert A. Vierkant; Brooke L. Fridley; Rebecca Sutphen; John R. McLaughlin; Steven A. Narod; Ellen L. Goode; Joellen M. Schildkraut; David Fenstermacher; Catherine M. Phelan; Thomas A. Sellers
Background: Mitochondria contribute to oxidative stress, a phenomenon implicated in ovarian carcinogenesis. We hypothesized that inherited variants in mitochondrial-related genes influence epithelial ovarian cancer (EOC) susceptibility. Methods: Through a multicenter study of 1,815 Caucasian EOC cases and 1,900 controls, we investigated associations between EOC risk and 128 single nucleotide polymorphisms (SNPs) from 22 genes/regions within the mitochondrial genome (mtDNA) and 2,839 nuclear-encoded SNPs localized to 138 genes involved in mitochondrial biogenesis (BIO, n = 35), steroid hormone metabolism (HOR, n = 13), and oxidative phosphorylation (OXP, n = 90) pathways. Unconditional logistic regression was used to estimate OR and 95% CI between genotype and case status. Overall significance of each gene and pathway was evaluated by using Fishers method to combine SNP-level evidence. At the SNP level, we investigated whether lifetime ovulation, hormone replacement therapy (HRT), and cigarette smoking were confounders or modifiers of associations. Results: Interindividual variation involving BIO was most strongly associated with EOC risk (empirical P = 0.050), especially for NRF1, MTERF, PPARGC1A, ESRRA, and CAMK2D. Several SNP-level associations strengthened after adjustment for nongenetic factors, particularly for MTERF. Statistical interactions with cigarette smoking and HRT use were observed with MTERF and CAMK2D SNPs, respectively. Overall variation within mtDNA, HOR, and OXP was not statistically significant (empirical P > 0.10). Conclusion: We provide novel evidence to suggest that variants in mitochondrial biogenesis genes may influence EOC susceptibility. Impact: A deeper understanding of the complex mechanisms implicated in mitochondrial biogenesis and oxidative stress may aid in developing strategies to reduce morbidity and mortality from EOC. Cancer Epidemiol Biomarkers Prev; 20(6); 1131–45. ©2011 AACR.
BMC Cancer | 2012
Michelle R. Iannacone; Wei Wang; Heather G. Stockwell; Kathleen O’Rourke; Anna R. Giuliano; Vernon K. Sondak; Jane L. Messina; Richard G. Roetzheim; Basil S. Cherpelis; Neil A. Fenske; Dana E. Rollison
BackgroundNon-melanoma skin cancer (NMSC), comprised of basal (BCC) and squamous (SCC) cell carcinomas, is the most common cancer in Caucasians. Ultraviolet radiation (UVR) exposure is the most important environmental risk factor for NMSC. However, the precise relationship between UVR and the risk of NMSC is complex, and the relationship may differ by skin cancer type.MethodsA case–control study was conducted among Florida residents to investigate measures of patterns (intermittent vs. continuous) and timing (childhood vs. adulthood) of sunlight exposure in BCC and SCC. Participants included 218 BCC and 169 SCC cases recruited from a university dermatology clinic and 316 controls with no history of skin or other cancers.ResultsA history of blistering sunburn (a measure of intermittent sunlight exposure) was associated with both BCC (OR = 1.96, 95% CI = 1.27-3.03) and SCC (OR = 2.02, 95% CI = 1.22-3.33). Additionally, having a job in the sun for ≥3 months for 10 years or longer (a measure of continuous sunlight exposure) was also associated with both BCC and SCC in our study population. With the exception of younger age at first blistering sunburn, measures of younger age at sunlight exposure tended to be associated with SCC, but not BCC risk.ConclusionsResults from the current study suggest that sunlight exposure is associated with both BCC and SCC risk regardless of the pattern in which the exposure was received (i.e. intermittent vs. continuous). The data also suggest that sunlight exposure at a younger age may be more important for SCC but not BCC, however additional studies are needed to further characterize sunlight exposure-response relationships in different types of NMSC.