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Dive into the research topics where Alexandra L. Hernandez is active.

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Featured researches published by Alexandra L. Hernandez.


Environmental Health Perspectives | 2000

Arsenic-Induced Skin Lesions among Atacameno People in Northern Chile despite Good Nutrition and Centuries of Exposure

Allan H. Smith; Alex P. Arroyo; D.N. Guha Mazumder; Michael J. Kosnett; Alexandra L. Hernandez; Martin Beeris; Meera M. Hira Smith; Lee E. Moore

It has been suggested that the indigenous Atacameño people in Northern Chile might be protected from the health effects of arsenic in drinking water because of many centuries of exposure. Here we report on the first intensive investigation of arsenic-induced skin lesions in this population. We selected 11 families (44 participants) from the village of Chiu Chiu, which is supplied with water containing between 750 and 800 microg/L inorganic arsenic. For comparison, 8 families (31 participants) were also selected from a village where the water contains approximately 10 microg/L inorganic arsenic. After being transported to the nearest city for blind assessment, participants were examined by four physicians with experience in studying arsenic-induced lesions. Four of the six men from the exposed village, who had been drinking the contaminated water for more than 20 years, were diagnosed with skin lesions due to arsenic, but none of the women had definite lesions. A 13-year-old girl had definite skin pigmentation changes due to arsenic, and a 19-year-old boy had both pigmentation changes and keratoses on the palms of his hands and the soles of his feet. Family interviews identified a wide range of fruits and vegetables consumed daily by the affected participants, as well as the weekly intake of red meat and chicken. However, the prevalence of skin lesions among men and children in the small population studied was similar to that reported with corresponding arsenic drinking water concentrations in both Taiwan and West Bengal, India--populations in which extensive malnutrition has been thought to increase susceptibility.


Aids and Behavior | 2006

Sexual Behavior Among Men Who have Sex with Women, Men, and Hijras in Mumbai, India—Multiple Sexual Risks

Alexandra L. Hernandez; Christina P. Lindan; Meenakshi Mathur; Maria Ekstrand; Purnima Madhivanan; Ellen S. Stein; Steven E. Gregorich; Sanjukta Kundu; Alka Gogate; Hema R. Jerajani

We describe the same-sex partnerships and sexual risk behavior of men attending sexually transmitted infection (STI) clinics in Mumbai, India. The HIV prevalence among 2,381 men sampled was 14%; 62% had a documented STI. Almost all men reported sex with women; additionally, 13% also reported having sex with other men, 13% reported sex with Hijras (male-to-female transgenders), and 11% had sex with all 3 genders. Men who had sex with men and/or Hijras as well as women, reported having greater numbers of partners, including female sex workers (FSW), and were more likely to engage in insertive anal and oral sex with women. The prevalence of HIV was higher among men having sex with Hijras (14%) or with all 3 genders (13%) than among men having sex with men and women (8%). A high proportion of men who attend STI clinics in Mumbai are behaviorally bi- or tri-sexual and have multiple partners with whom they engage in risky sex. STI/HIV prevention programs should not assume that men only have sex with women.


Sexually Transmitted Diseases | 2005

Alcohol use by men is a risk factor for the acquisition of sexually transmitted infections and human immunodeficiency virus from female sex workers in Mumbai, India

Purnima Madhivanan; Alexandra L. Hernandez; Alka Gogate; Ellen Stein; Steven E. Gregorich; Maninder Singh Setia; Sameer Kumta; Maria Ekstrand; Meenakshi Mathur; Hema R. Jerajani; Christina P. Lindan

Objective: We investigated whether men who were under the influence of alcohol when visiting female sex workers (FSW) were at greater risk for sexually transmitted infections (STI) and human immunodeficiency virus (HIV). Study: A cross-sectional analysis using baseline data from a randomized controlled trial of an HIV prevention intervention for high-risk men in Mumbai, India. Results: The overall HIV prevalence among 1741 men sampled was 14%; 64% had either a confirmed STI or HIV; 92% reported sex with an FSW, of whom 66% reported having sex while under the influence of alcohol (SUI). SUI was associated with unprotected sex (odds ratio [OR]: 3.1; 95% confidence interval [CI], 2.3–4.1), anal sex (OR: 1.5; 1.1–2.0), and more than10 FSW partners (OR: 2.2; 1.8–2.7). SUI was independently associated with having either an STI or HIV (OR: 1.5; 1.2–1.9). Conclusion: Men who drink alcohol when visiting FSWs engage in riskier behavior and are more likely to have HIV and STIs. Prevention programs in India need to raise awareness of this relationship.


Journal of Asthma | 2002

Self-reported asthma prevalence in adults in California

Julie Von Behren; Richard Kreutzer; Alexandra L. Hernandez

Data from the 1998 California Behavioral Risk Factor Surveillance System (BRFSS) were examined. The BRFSS is an ongoing statewide telephone survey of randomly selected adults. The prevalence of self-reported lifetime asthma was 13.6% and the prevalence of active asthma was 6.6%. Prevalence rates were highest among African-Americans and lowest among Hispanics. Associations between asthma and gender, obesity, smoking, depression, migraine, and income were also examined. Active asthma was associated with low income, smoking, obesity, migraine, and depression in women, but not in men. The relationships observed suggest complex interactions between asthma and other chronic conditions, gender, and life-style.


JAMA Internal Medicine | 2010

An Intensive Behavioral Weight Loss Intervention and Hot Flushes in Women

Alison J. Huang; Leslee L. Subak; Rena R. Wing; Delia Smith West; Alexandra L. Hernandez; Judy Macer; Deborah Grady

BACKGROUND Higher body mass index is associated with worse hot flushes during menopause but the effect of weight loss on flushing is unclear. METHODS Self-administered questionnaires were used to assess bothersome hot flushes in a 6-month randomized controlled trial of an intensive behavioral weight loss program (intervention) vs a structured health education program (control) in 338 women who were overweight or obese and had urinary incontinence. Weight, body mass index, abdominal circumference, physical activity, calorie intake, blood pressure, and physical and mental functioning were assessed at baseline and at 6 months. Repeated-measures proportional odds models examined intervention effects on bothersome hot flushes and potential mediating factors. RESULTS Approximately half of participants (n = 154) were at least slightly bothered by hot flushes at baseline. Among these women, the intervention was associated with greater improvement in bothersome flushes vs control (odds ratio [OR] for improvement by 1 Likert category, 2.25; 95% confidence interval [CI], 1.20-4.21). Reductions in weight (OR, 1.32; 95% CI, 1.08-1.61; per 5-kg decrease), body mass index (1.17; 1.05-1.30; per 1-point decrease), and abdominal circumference (1.32; 1.07-1.64; per 5-cm decrease) were each associated with improvement in flushing, but changes in physical activity, calorie intake, blood pressure, and physical and mental functioning were not related. The effect of the intervention on flushing was modestly diminished after adjustment for multiple potential mediators (OR, 1.92; 95% CI, 0.95-3.89). CONCLUSION Among women who were overweight or obese and had bothersome hot flushes, an intensive behavioral weight loss intervention resulted in improvement in flushing relative to control. Trial Registration clinicaltrials.gov Identifier: NCT00091988.


Radiology | 2012

Lumbosacral Transitional Vertebrae: Association with Low Back Pain

Lorenzo Nardo; Hamza Alizai; Warapat Virayavanich; F. Liu; Alexandra L. Hernandez; J.A. Lynch; Michael C. Nevitt; Charles E. McCulloch; Nancy E. Lane; Thomas M. Link

PURPOSE To assess the prevalence and degree of lumbosacral transitional vertebrae (LSTV) in the Osteoarthritis Initiative (OAI) cohort, to assess whether LSTV correlates with low back pain (LBP) and buttock pain, and to assess the reproducibility of grading LSTV. MATERIALS & METHODS Institutional review board approval was obtained, and informed consent documentation was approved for the study protocol. Standard standing pelvic radiographs that included the transverse processes of L5 were graded according to Castellvi classification of LSTV in 4636 participants (1992 men and 2804 women; aged 45-80 years) from the OAI cohort. These data were correlated with prevalence and severity of LBP and buttock pain. RESULTS Prevalence of LSTV was 18.1% (841 of 4636), with a higher rate in men than in women (28.1% vs 11.1%, respectively; P<.001). Of the 841 individuals with LSTV, 41.72% were type I (dysplastic enlarged transverse process), 41.4% were type II (pseudoarticulation), 11.5% were type III (fusion), and 5.2% were type IV (one transverse process fused and one with pseudoarticulation). Of the participants without LSTV, 53.9% reported LBP, while the prevalence of LBP for types I, II, III, and IV was 46%, 73%, 40%, and 66%, respectively (P<.05, χ2 test). Types II and IV had higher prevalence and severity of LBP and buttock pain (P<.001). CONCLUSION LSTV types II and IV positively correlate with prevalence and severity of LBP and buttock pain.


American Journal of Obstetrics and Gynecology | 2009

Association between urinary incontinence and depressive symptoms in overweight and obese women.

Vivian W. Sung; Delia Smith West; Alexandra L. Hernandez; Thomas L. Wheeler; Deborah L. Myers; Leslee L. Subak

OBJECTIVE The objective of the study was to determine the association between urinary incontinence (UI) and depressive symptoms. STUDY DESIGN The study was a cross-sectional study of 338 incontinent and overweight women at baseline in the Program to Reduce Incontinence by Diet and Exercise trial. Depressive symptoms were defined as a Beck Depression Inventory score of 10 or greater. UI frequency was determined by a 7-day voiding diary. Symptom bother and quality of life were determined using the Urogenital Distress Inventory (UDI) and the Incontinence Impact Questionnaire (IIQ). Multivariable regression was used to estimate the association between UI and depressive symptoms. RESULTS Women with depressive symptoms (n = 101) reported a higher mean number of UI episodes per week (28 vs 23; P = .005) and higher (worse) mean scores on the UDI (176 vs 162; P = .02) and IIQ (136 vs 97; P < .001) compared with women without depressive symptoms. The risk of having depressive symptoms increased with each 7-episode increase in UI per week (adjusted odds ratio [AOR], 1.10; 95% confidence interval [CI], 1.01-1.21), each 50-point increase in UDI (AOR, 1.27; 95% CI, 1.01-1.60), and each 50-point increase in IIQ (AOR, 1.44; 95% CI, 1.22-1.71). CONCLUSION Urinary incontinence frequency, symptom bother, and quality of life are independently associated with depressive symptoms in overweight and obese women.


International Journal of Obesity | 2012

Adipokines and Body Fat Composition in South Asians: Results of the Metabolic syndrome and Atherosclerosis in South Asians Living in America (MASALA) Study

Arti D. Shah; Alexandra L. Hernandez; Deepika Mathur; Matthew J. Budoff; Alka M. Kanaya

Objective:To investigate whether leptin and adiponectin are associated with body fat composition in a South Asian population independent of metabolic variables.Design:Cross-sectional study.Subjects:150 South Asian men and women, between the ages of 45–79 years, in the San Francisco Bay Area without pre-existing clinical cardiovascular disease.Measurements:Blood samples were obtained to measure glucose metabolism variables, lipid profiles and adipokines. Total body fat was determined using dual-energy X-ray absorptiometry. Abdominal computed tomography was used to measure subcutaneous, visceral and hepatic fat.Results:Average body mass index (BMI) was overweight at 26.1±4.6 kg m−2 and did not differ by sex. However, women had significantly more total body fat (P<0.001) and subcutaneous fat (P<0.001) than men, whereas men had significantly more visceral fat (P<0.001) and hepatic fat (P=0.04) than women. Women had significantly higher levels of adiponectin (P<0.01) and leptin (P<0.01). In sex-stratified analyses, leptin was strongly associated with all-body composition measures in women (P<0.05) as well as in men (P<0.05 except for hepatic fat), whereas there was an insignificant trend towards an inverse association between adiponectin and body composition in both women and men, which was significant in combined bivariate analyses. In multivariate analyses, leptin was strongly associated with all measures of adiposity, including BMI (P<0.001), total body fat (P<0.001), visceral fat (P<0.001) and hepatic fat (P=0.01). However, adiponectins inverse association with adiposity was significantly attenuated by high-density lipoprotein (HDL), triglycerides and insulin resistance. The association between adipokines and diabetes was markedly attenuated after adjusting for body composition.Conclusion:Despite only modestly elevated BMI, South Asians have elevated levels of total and regional adiposity. Leptin is strongly associated with adiposity, whereas adiponectins association with adiposity is attenuated by metabolic variables in South Asians. Adipokines in association with adiposity have an important role in the development of diabetes.


American Journal of Obstetrics and Gynecology | 2009

Fecal incontinence in obese women with urinary incontinence: prevalence and role of dietary fiber intake.

Alayne D. Markland; Holly E. Richter; Kathryn L. Burgio; Charlotte Bragg; Alexandra L. Hernandez; Leslee L. Subak

OBJECTIVE This study estimates the prevalence of fecal incontinence (FI) in overweight and obese women with urinary incontinence and compares dietary intake in women with and without FI. STUDY DESIGN A total of 336 incontinent and overweight women in the Program to Reduce Incontinence by Diet and Exercise clinical trial were included. FI was defined as monthly or greater loss of mucus, liquid, or solid stool. Dietary intake was quantified using the Block Food Frequency Questionnaire. RESULTS Women had a mean (+/- SD) age of 53 +/- 10 years, body mass index of 36 +/- 6 kg/m(2), and 19% were African American. Prevalence of FI was 16% (n = 55). In multivariable analyses, FI was independently associated with low fiber intake, higher depressive symptoms, and increased urinary tract symptoms (all P < .05). CONCLUSION Overweight and obese women report a high prevalence of monthly FI associated with low dietary fiber intake. Increasing dietary fiber may be a treatment for FI.


AIDS | 2014

Incidence of and risk factors for type-specific anal human papillomavirus infection among HIV-positive MSM.

Alexandra L. Hernandez; Jimmy T. Efird; Elizabeth A. Holly; Berry Jm; Naomi Jay; Joel M. Palefsky

Objective:HIV-positive MSM are at increased risk of anal human papillomavirus (HPV) infection compared with men in the general population, and little is known about the natural history of anal HPV infection in this population. The objective of this study was to determine the incidence of and risk factors for anal type-specific HPV infection. Design:Prospective cohort study. Methods:HIV-positive MSM were evaluated for anal HPV DNA, lifestyle factors, and sexual risk behaviors every 6 months for at least 2 years. Results:The overall incidence rate of detectable type-specific anal HPV infection was 21.3 per 100 person-years [95% confidence interval (CI) 17.7–25.4] and was 13.3/100 person-years (10.5–16.6) for oncogenic HPV types. The most common incident infections were HPV 18 (3.7/100 person-years) and HPV 16 (3.5/100 person-years). An increased number of recent partners with whom the participant was the receptive partner [odds ratio (OR) 2.9 (1.6–5.1) 8+ partners vs. 0–1], an increased number of new partners in which the participant was the receptive partner [OR 1.03 (1.01–1.1) per partner], an increased number of new oral–anal contact partners in which the participant was the receptive partner [OR 1.1 (1.03–1.1) per partner], and the frequency of receptive anal intercourse [OR 1.1 (1.03–1.1) per act] all significantly increased the odds of incident HPV infection (P ⩽ 0.05). Conclusion:HIV-positive MSM have a high incidence of oncogenic anal HPV infection. Recent receptive anal sexual behaviors, including receptive anal intercourse and receptive oral–anal contact, are the most important risk factors for incident anal HPV infection.

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Allan H. Smith

University of California

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Michael J. Kosnett

University of Colorado Denver

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Lee E. Moore

National Institutes of Health

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Naomi Jay

University of California

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Alex P. Arroyo

University of Antofagasta

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Alayne D. Markland

University of Alabama at Birmingham

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Alka M. Kanaya

University of California

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