Epidemiology & Biostatistics Research Works
Permanent URI for this collectionhttp://hdl.handle.net/1903/7128
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Item Census Tract Food Tweets and Chronic Disease Outcomes in the U.S., 2015–2018(MDPI, 2019-03-18) Huang, Yuru; Huang, Dina; Nguyen, Quynh C.There is a growing recognition of social media data as being useful for understanding local area patterns. In this study, we sought to utilize geotagged tweets—specifically, the frequency and type of food mentions—to understand the neighborhood food environment and the social modeling of food behavior. Additionally, we examined associations between aggregated food-related tweet characteristics and prevalent chronic health outcomes at the census tract level. We used a Twitter streaming application programming interface (API) to continuously collect ~1% random sample of public tweets in the United States. A total of 4,785,104 geotagged food tweets from 71,844 census tracts were collected from April 2015 to May 2018. We obtained census tract chronic disease outcomes from the CDC 500 Cities Project. We investigated associations between Twitter-derived food variables and chronic outcomes (obesity, diabetes and high blood pressure) using the median regression. Census tracts with higher average calories per tweet, less frequent healthy food mentions, and a higher percentage of food tweets about fast food had higher obesity and hypertension prevalence. Twitter-derived food variables were not predictive of diabetes prevalence. Food-related tweets can be leveraged to help characterize the neighborhood social and food environment, which in turn are linked with community levels of obesity and hypertension.Item A method for analyzing censored survival phenotype with gene expression data(Springer Nature, 2008-10-06) Wu, Tongtong; Sun, Wei; Yuan, Shinsheng; Chen, Chun-Houh; Li, Ker-ChauSurvival time is an important clinical trait for many disease studies. Previous works have shown certain relationship between patients' gene expression profiles and survival time. However, due to the censoring effects of survival time and the high dimensionality of gene expression data, effective and unbiased selection of a gene expression signature to predict survival probabilities requires further study. We propose a method for an integrated study of survival time and gene expression. This method can be summarized as a two-step procedure: in the first step, a moderate number of genes are pre-selected using correlation or liquid association (LA). Imputation and transformation methods are employed for the correlation/LA calculation. In the second step, the dimension of the predictors is further reduced using the modified sliced inverse regression for censored data (censorSIR). The new method is tested via both simulated and real data. For the real data application, we employed a set of 295 breast cancer patients and found a linear combination of 22 gene expression profiles that are significantly correlated with patients' survival rate. By an appropriate combination of feature selection and dimension reduction, we find a method of identifying gene expression signatures which is effective for survival prediction.Item Hepatitis B vaccinations among Koreans: Results from 2005 Korea National Cancer Screening Survey(Springer Nature, 2009-11-25) Juon, Hee-Soon; Choi, Kui Son; Park, Eun-Cheol; Kwak, Min-Son; Lee, SunminLiver cancer is one of most commonly diagnosed cancers among Koreans. Chronic hepatitis B virus (HBV) infection is a major risk factor for liver cancer. HBV infection can be prevented by effective screening and vaccination programs. The purpose of this study is to examine the status of HBV infection and the predictors associated with HBV vaccination. The study population was derived from the 2005 Korea National Cancer Screening Survey (KNCSS). The KNCSS is an annual cross-sectional survey that uses a nationally-representative random sampling to investigate cancer screening rates. A total of 1,786 Koreans over 40 years of age participated in this study. Of all the participants, 5.9% reported HBV positive (HBsAg+, HBsAb-), 41.8% were HBV negative but protected (HBsAg-, HBsAb+), and 52.3% were unprotected (HBsAg-, HBsAb-). Among unprotected individuals (n = 934), 23.1% reported to have received the vaccination. About half of those who had vaccinations completed the 3-shot vaccine series. In multiple analyses, education, having private cancer insurance, alcohol use, having regular check-up, and doing regular exercise were associated with completed HBV vaccination. This study result suggests that we need a liver cancer education program to increase HBV awareness and to increase the liver cancer prevention message among low educated populations.Item Nitric oxide is negatively correlated to pain during acute inflammation(Springer Nature, 2010-09-15) Hamza, May; Wang, Xiao-Min; Wu, Tongtong; Brahim, Jaime S; Rowan, Janet S; Dionne, Raymond AThe role that nitric oxide (NO) plays in modulating pain in the periphery is unclear. We show here, the results of two independent clinical studies (microdialysis and gene expression studies) and a pilot dose finding study (glyceryl trinitrate study), to study the role of NO in the early phase of acute inflammatory pain following oral surgery. The effect of ketorolac on NO production and nitric oxide synthase (NOS) gene expression was also studied. Microdialysis samples showed significantly higher levels of NO at the first 100 min compared to the last 80 minutes in the placebo treated group. In the ketorolac group, on the other hand, NO levels gradually decreased over the first 60 min but were similar to placebo over the later 100-180 min, with no significant change in NO level over time. The levels of NO were negatively correlated to pain intensity scores. Local infusion of the NO donor glyceryl trinitrate at the site of surgery, showed a small analgesic effect that did not reach statistical significance in the sample size used. While the gene expression of iNOS and eNOS were not up-regulated, 3 hours after surgery, nNOS was downregulated in both treatment groups and eNOS gene expression was significantly lower in the ketorolac group compared to the placebo group. Further, there was a positive correlation between the change in gene expression of nNOS and eNOS in the placebo goup but not in the ketorolac group. We suggest that at this early stage of inflammatory pain in man, NO is analgesic in the periphery. Further, ketorolac down-regulates eNOS gene expression.Item Randomized trial of achieving healthy lifestyles in psychiatric rehabilitation: the ACHIEVE trial(Springer Nature, 2010-12-13) Casagrande, Sarah S; Jerome, Gerald J; Dalcin, Arlene T; Dickerson, Faith B; Anderson, Cheryl A; Appel, Lawrence J; Charleston, Jeanne; Crum, Rosa M; Young, Deborah R; Guallar, Eliseo; Frick, Kevin D; Goldberg, Richard W; Oefinger, Meghan; Finkelstein, Joseph; Oladapo Fred-Omojole; Gennusa, Joseph V III; Fred-Omojole, Oladapo; Campbell, Leslie M; Wang, Nae-Yuh; Daumit, Gail LOverweight and obesity are highly prevalent among persons with serious mental illness. These conditions likely contribute to premature cardiovascular disease and a 20 to 30 percent shortened life expectancy in this vulnerable population. Persons with serious mental illness need effective, appropriately tailored behavioral interventions to achieve and maintain weight loss. Psychiatric rehabilitation day programs provide logical intervention settings because mental health consumers often attend regularly and exercise can take place on-site. This paper describes the Randomized Trial of Achieving Healthy Lifestyles in Psychiatric Rehabilitation (ACHIEVE). The goal of the study is to determine the effectiveness of a behavioral weight loss intervention among persons with serious mental illness that attend psychiatric rehabilitation programs. Participants randomized to the intervention arm of the study are hypothesized to have greater weight loss than the control group. A targeted 320 men and women with serious mental illness and overweight or obesity (body mass index ≥ 25.0 kg/m2) will be recruited from 10 psychiatric rehabilitation programs across Maryland. The core design is a randomized, two-arm, parallel, multi-site clinical trial to compare the effectiveness of an 18-month behavioral weight loss intervention to usual care. Active intervention participants receive weight management sessions and physical activity classes on-site led by study interventionists. The intervention incorporates cognitive adaptations for persons with serious mental illness attending psychiatric rehabilitation programs. The initial intensive intervention period is six months, followed by a twelve-month maintenance period in which trained rehabilitation program staff assume responsibility for delivering parts of the intervention. Primary outcomes are weight loss at six and 18 months. Evidence-based approaches to the high burden of obesity and cardiovascular disease risk in person with serious mental illness are urgently needed. The ACHIEVE Trial is tailored to persons with serious mental illness in community settings. This multi-site randomized clinical trial will provide a rigorous evaluation of a practical behavioral intervention designed to accomplish and sustain weight loss in persons with serious mental illness.Item Validity of self-reported leisure-time sedentary behavior in adolescents(Springer Nature, 2011-02-11) Affuso, Olivia; Stevens, June; Catellier, Diane; McMurray, Robert G; Ward, Dianne S; Lytle, Leslie; Sothern, Melinda S; Sothern, Melinda STo evaluate the concordance between leisure-time sedentary behavior in adolescents assessed by an activity-based questionnaire and accelerometry. A convenience sample of 128 girls and 73 boys, 11-15 years of age (12.6 ± 1.1 years) from six states across the United States examined as part of the feasibility studies for the Trial of Activity in Adolescent Girls (TAAG). Three days of self-reported time spent watching TV/videos, using computers, playing video/computer games, and talking on the phone was assessed using a modified version of the Self-Administered Physical Activity Checklist (SAPAC). Criterion measure of sedentary behavior was via accelerometry over three days using a cut point of < 50 counts · 30 sec-1 epoch. Comparisons between sedentary behavior by the two instruments were made. Adolescents generally underestimated minutes of sedentary behavior compared to accelerometry-measured minutes. The overall correlation between minutes of sedentary behavior by self-report and accelerometry was weak (Spearman r = 0.14; 95% CI 0.05, 0.23). Adjustment of sedentary minutes of behavior for total minutes assessed using either percentages or the residuals method tended to increase correlations slightly. However, regression analyses showed no significant association between self-reported sedentary behavior and minutes of sedentary behavior captured via accelerometry. These findings suggest that the modified 3-day Self-Administered Physical Activity Checklist is not a reliable method for assessing sedentary behavior. It is recommended that until validation studies for self-report instruments of sedentary behavior demonstrate validity, objective measures should be used.Item Microarray analysis of genes associated with cell surface NIS protein levels in breast cancer(Springer Nature, 2011-10-11) Beyer, Sasha J; Zhang, Xiaoli; Jimenez, Rafael E; Lee, Mei-Ling T; Richardson, Andrea L; Huang, Kun; Jhiang, Sissy MNa+/I- symporter (NIS)-mediated iodide uptake allows radioiodine therapy for thyroid cancer. NIS is also expressed in breast tumors, raising potential for radionuclide therapy of breast cancer. However, NIS expression in most breast cancers is low and may not be sufficient for radionuclide therapy. We aimed to identify biomarkers associated with NIS expression such that mechanisms underlying NIS modulation in human breast tumors may be elucidated. Published oligonucleotide microarray data within the National Center for Biotechnology Information Gene Expression Omnibus database were analyzed to identify gene expression tightly correlated with NIS mRNA level among human breast tumors. NIS immunostaining was performed in a tissue microarray composed of 28 human breast tumors which had corresponding oligonucleotide microarray data available for each tumor such that gene expression associated w ith cell surface NIS protein level could be identified. NIS mRNA levels do not vary among breast tumors or when compared to normal breast tissues when detected by Affymetrix oligonucleotide microarray platforms. Cell surface NIS protein levels are much more variable than their corresponding NIS mRNA levels. Despite a limited number of breast tumors examined, our analysis identified cysteinyl-tRNA synthetase as a biomarker that is highly associated with cell surface NIS protein levels in the ER-positive breast cancer subtype. Further investigation on genes associated with cell surface NIS protein levels within each breast cancer molecular subtype may lead to novel targets for selectively increasing NIS expression/function in a subset of breast cancers patients.Item Validation of a susceptibility, benefits, and barrier scale for mammography screening among Peruvian women: a cross-sectional study(Springer Nature, 2011-12-07) Huaman, Moises A; Kamimura-Nishimura, Kelly I; Kanamori, Mariano; Siu, Alejandro; Lescano, Andres GPerceived beliefs about breast cancer and breast cancer screening are important predictors for mammography utilization. This study adapted and validated the Champion's scale in Peru. This scale measures perceived susceptibility for breast cancer and perceived benefits and barriers for mammography. A cross-sectional study was conducted among women ages 40 to 65 attending outpatient gynecology services in a public hospital in Peru. A group of experts developed and pre-tested a Spanish version of the Champion's scale to assess its comprehensibility (N = 20). Factor analysis, internal consistency, and test-retest reliability analyses were performed (N = 285). Concurrent validity compared scores from participants who had a mammogram and those who did not have it in the previous 15 months. T-test and multiple regression analysis adjusting for socio-demographic factors, mammography knowledge and other preventive behaviors were performed. The construct validity and reliability were optimal. Cronbach-Alpha coefficients were 0.75 (susceptibility), 0.72 (benefits) and 0.86 (barriers). Concurrent validity analysis showed an association between barriers and mammography screening use in bivariate (22.3 ± 6.7 vs. 30.2 ± 7.6; p < 0.001) and multiple regression analysis (OR = 0.28, 95% CI = 0.18-0.43). Ages 50-60 years (OR = 2.35, 95% CI = 1.19-4.65), history of prior Papanicolaou test (OR = 3.69, 95% CI = 1.84-7.40), and knowledge about breast cancer and mammography (OR = 3.69, 95% CI = 1.84-7.40) were also independently associated with mammography screening use. Concurrent validity analysis showed that the Champion's scale has important limitations for assessing perceived susceptibility for breast cancer and perceived benefits for mammography among Peruvian women. There is still a need for developing valid and reliable instruments for measuring perceived beliefs about breast cancer and mammography screening among Peruvian women.Item Allostatic load amplifies the effect of blood lead levels on elevated blood pressure among middle-aged U.S. adults: a cross-sectional study(Springer Nature, 2013-08-16) Zota, Ami R; Shenassa, Edmond D; Morello-Frosch, RachelScientists and regulators have sought to understand whether and how physiologic dysregulation due to chronic stress exposure may enhance vulnerability to the adverse health effects of toxicant exposures. We conducted a cross-sectional study to determine whether allostatic load (AL), a composite measure of physiologic response to chronic exposure to stress, amplifies the effect of lead exposure on blood pressure among middle-aged adults. We analyzed associations between blood lead levels and blood pressure in a nationally representative sample of 8,194 U.S. adults (aged 40-65 years) participating in the National Health and Nutritional Examination Survey, 1999--2008. Outcomes were elevated systolic (≥ 140 mm Hg) and diastolic (≥ 90 mm Hg) blood pressure. AL was defined as the aggregate score of seven components, reflecting dysregulation of the cardiovascular, inflammatory, and endocrine systems. Logistic regression models showed a linear dose-response relationship for quintiles of blood lead and elevated systolic blood pressure in the high AL group (p = 0.03) but not the low AL group (p = 0.24). Similarly, the relationship between lead exposure and elevated diastolic blood pressure was stronger among the high AL group than the low AL group. Within the high AL group, the fourth and fifth quintiles had significantly elevated odds of elevated blood pressure compared to lowest quintile [OR = 1.92, (95% CI, 1.07, 3.47) and OR =2.28 (95% CI, 1.33, 3.91), respectively]. In the low AL group, none of the quintile effects were significantly different than the referent group although there was evidence of a linear trend (p =0.03). The lead by AL interaction term was not statistically significant for either systolic or diastolic blood pressure models. Results suggest that higher AL may amplify the adverse effects of lead on blood pressure. Future research should assess the implications of cumulative exposures to environmental and social stressors for regulatory decision-making.Item Syndemics of syphilis, HCV infection, and methamphetamine use along the east coast of China(Springer Nature, 2014-02-17) Liao, Meizhen; Kang, Dianmin; Tao, Xiaorun; Cox, Catherine; Qian, Yuesheng; Wang, Guoyong; Yang, Cui; Zhu, XiaoYan; Zhang, Na; Bi, Zhenqiang; Jia, YujiangAn upsurge in club drug use has been observed in recent years in some cities of China, especially methamphetamine, which is quickly replacing heroin to become the most widespread drug across the nation. This study investigated the type of drugs used, syphilis and hepatitis C virus (HCV) infection and the correlates for syphilis, HCV and unprotected commercial sex behavior among drug users in two cities along the east coast of China. A cross-sectional survey conducted in 2010 provided demographics, sexual and drug use behaviors, HIV knowledge and the utilization of intervention services among drug users. Blood samples were tested for HIV, syphilis, and HCV infection. Of 805 eligible participants, 0.2% were infected with HIV, 3.7% with HCV, and 9.6% with syphilis. Of the participants, 96.6% were methamphetamine users, 11.9% reported ever having used ≥2 types of these drugs, and 11.4% reported ever injecting drugs. In the multivariable logistic regression analysis, participants infected with syphilis were more likely to be female (adjusted odds ratio (AOR)=2.8, 95% confidence interval (CI): 1.2-6.5), have ever had commercial sex in the past 12 months (AOR=2.0, 95% CI: 1.0-3.9), be infected with HCV (AOR=12.1, 95% CI: 4.1-20.3) and less likely to have ever had sex with regular partners in the past 12 months (AOR=0.2, 95% CI: 0.1-0.6). Participants infected with HCV were more likely to have ever injected drugs (AOR=2.7, 95% CI: 1.1-6.5) and be infected with syphilis (AOR=8.0, 95% CI: 3.5-18.0). Participants who had unprotected sex with commercial sex partners in the last sexual encounter were more likely to be female (AOR=2.9, 95% CI:1.7-4.9), have middle school or lower level education (AOR=3.4, 95% CI:2.0-5.5), never have received intervention in the last year (AOR=2.1, 95%CI:1.2-3.6) and be infected with syphilis (AOR=4.2, 95% CI:2.4-7.4). Methamphetamine is the predominant drug used among the drug users, the prevalence of syphilis and HCV infection are alarmingly high, and unprotected commercial sex was common among this group. The findings highlight the need for effective, multifaceted interventions addressing sexual and drug use-related risky behaviors among this group. Further research is needed to better understand the causal pathway of the syndemics.