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Dive into the research topics where Frank Z. Stanczyk is active.

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Featured researches published by Frank Z. Stanczyk.


The Lancet | 1992

5-alpha-reductase activity and risk of prostate cancer among japanese and US white and black males

R. K. Ross; Leslie Bernstein; M. C. Pike; B. E. Henderson; R.A. Lobo; Frank Z. Stanczyk; H. Shimizu

The incidence of prostate cancer varies widely between countries and ethnic groups. Black-Americans have the highest incidence rates world wide, whereas native Japanese have among the lowest. The reasons for this risk differential are unknown, although we have previously shown that higher circulating testosterone concentrations in young adult black men compared with young adult white men may explain the underlying differences in subsequent prostate cancer incidence between these two populations. We have now compared serum testosterone concentrations in young adult Japanese men with those of young adult whites and blacks, but found no significant differences. However, these white and black men had significantly higher values of 3 alpha, 17 beta androstanediol glucuronide (31% and 25% higher, respectively) and androsterone glucuronide (50% and 41% higher, respectively) than Japanese subjects. These two androgens are indices of 5 alpha-reductase activity. Our results raise the possibility that reduced 5 alpha-reductase activity has a role in producing the low prostate cancer incidence rates among Japanese. This finding may have important implications for prostate cancer prevention.


The Journal of Clinical Endocrinology and Metabolism | 2008

Postmenopausal women with a history of irregular menses and elevated androgen measurements at high risk for worsening cardiovascular event-free survival: results from the National Institutes of Health--National Heart, Lung, and Blood Institute sponsored Women's Ischemia Syndrome Evaluation.

Leslee J. Shaw; C. Noel Bairey Merz; Ricardo Azziz; Frank Z. Stanczyk; George Sopko; Glenn D. Braunstein; Sheryl F. Kelsey; Kevin E. Kip; Rhonda M. Cooper-DeHoff; B. Delia Johnson; Viola Vaccarino; Steven E. Reis; Vera Bittner; T. Keta Hodgson; William J. Rogers; Carl J. Pepine

BACKGROUND Women with polycystic ovary syndrome (PCOS) have a greater clustering of cardiac risk factors. However, the link between PCOS and cardiovascular (CV) disease is incompletely described. OBJECTIVE The aim of this analysis was to evaluate the risk of CV events in 390 postmenopausal women enrolled in the National Institutes of Health-National Heart, Lung, and Blood Institute (NIH-NHLBI) sponsored Womens Ischemia Syndrome Evaluation (WISE) study according to clinical features of PCOS. METHODS A total of 104 women had clinical features of PCOS defined by a premenopausal history of irregular menses and current biochemical evidence of hyperandrogenemia. Hyperandrogenemia was defined as the top quartile of androstenedione (> or = 701 pg/ml), testosterone (> or = 30.9 ng/dl), or free testosterone (> or = 4.5 pg/ml). Cox proportional hazard model was fit to estimate CV death or myocardial infarction (n = 55). RESULTS Women with clinical features of PCOS were more often diabetic (P < 0.0001), obese (P = 0.005), had the metabolic syndrome (P < 0.0001), and had more angiographic coronary artery disease (CAD) (P = 0.04) compared to women without clinical features of PCOS. Cumulative 5-yr CV event-free survival was 78.9% for women with clinical features of PCOS (n = 104) vs. 88.7% for women without clinical features of PCOS (n = 286) (P = 0.006). PCOS remained a significant predictor (P < 0.01) in prognostic models including diabetes, waist circumference, hypertension, and angiographic CAD as covariates. CONCLUSION Among postmenopausal women evaluated for suspected ischemia, clinical features of PCOS are associated with more angiographic CAD and worsening CV event-free survival. Identification of postmenopausal women with clinical features of PCOS may provide an opportunity for risk factor intervention for the prevention of CAD and CV events.


Frontiers in Neuroendocrinology | 2008

Progesterone Receptors: Form and Function in Brain

Roberta Diaz Brinton; Richard F. Thompson; Michael R. Foy; Michel Baudry; Jun Ming Wang; Caleb E. Finch; Todd E. Morgan; Christian J. Pike; Wendy J. Mack; Frank Z. Stanczyk; Jon Nilsen

Emerging data indicate that progesterone has multiple non-reproductive functions in the central nervous system to regulate cognition, mood, inflammation, mitochondrial function, neurogenesis and regeneration, myelination and recovery from traumatic brain injury. Progesterone-regulated neural responses are mediated by an array of progesterone receptors (PR) that include the classic nuclear PRA and PRB receptors and splice variants of each, the seven transmembrane domain 7TMPRbeta and the membrane-associated 25-Dx PR (PGRMC1). These PRs induce classic regulation of gene expression while also transducing signaling cascades that originate at the cell membrane and ultimately activate transcription factors. Remarkably, PRs are broadly expressed throughout the brain and can be detected in every neural cell type. The distribution of PRs beyond hypothalamic borders, suggests a much broader role of progesterone in regulating neural function. Despite the large body of evidence regarding progesterone regulation of reproductive behaviors and estrogen-inducible responses as well as effects of progesterone metabolite neurosteroids, much remains to be discovered regarding the functional outcomes resulting from activation of the complex array of PRs in brain by gonadally and/or glial derived progesterone. Moreover, the impact of clinically used progestogens and developing selective PR modulators for targeted outcomes in brain is a critical avenue of investigation as the non-reproductive functions of PRs have far-reaching implications for hormone therapy to maintain neurological health and function throughout menopausal aging.


Annals of Internal Medicine | 2008

Serum 25-Hydroxyvitamin D Concentrations and Risk for Hip Fractures

Jane A. Cauley; Andrea Z. LaCroix; LieLing Wu; Mara J. Horwitz; Michelle E. Danielson; D. C. Bauer; Jennifer Lee; Rebecca D. Jackson; John Robbins; Chunyuan Wu; Frank Z. Stanczyk; Meryl S. LeBoff; Jean Wactawski-Wende; Gloria E. Sarto; Judith K. Ockene; Steven R. Cummings

Context Vitamin D supplementation may help prevent fractures, but the relationship between blood vitamin D concentrations and fracture risk is unclear. Contribution These authors observed an increased risk for hip fracture among women with lower serum 25-hydroxyvitamin D [25(OH) vitamin D] concentrations that was independent of measures of frailty, body mass index, physical function, and falls. Caution The authors did not measure bone mineral density (BMD), so they could not determine whether 25(OH) vitamin D concentrations give different information about fracture risk than that offered by BMD. Implication Low serum 25(OH) vitamin D concentrations seem to be associated with a higher hip fracture risk. The Editors Vitamin D deficiency is common in older adults, especially during the winter (1) and in homebound populations (2), general medical inpatients (3), and community-dwelling women admitted to the hospital with acute hip fracture (4). A recently published evidence-based report on vitamin D and bone health (5) found the level of evidence for an association between serum 25-hydroxyvitamin D [25(OH) vitamin D] concentrations and fracture risk to be inconsistent (5). Since publication of that review, 1 prospective study (6) reported no relationship between serum 25(OH) vitamin D concentrations and fractures, whereas another (7) reported a significantly lower risk for hip fracture with 25(OH) vitamin D concentrations greater than 60 nmol/L. Vitamin D concentration could be associated with fractures in several ways. It could influence muscle strength and balance, both of which contribute to falls and disability (810). The association between 25(OH) vitamin D concentrations and fracture may also be influenced by renal function, because renal insufficiency has been linked to fracture (11) and to vitamin D deficiency (12). Several interactions between vitamin D and estrogen receptors have been described (13); hormone therapy has been shown to reverse abnormalities in vitamin D metabolism (14), and low vitamin D concentrations have also been linked to higher bone turnover (15, 16). Thus, sex-steroid hormones and bone turnover could contribute to the association between 25(OH) vitamin D concentration and fractures. We conducted a nested casecontrol study within the WHI-OS (Womens Health Initiative Observational Study) among 400 case-patients with adjudicated incident hip fracture and 400 control participants. We tested whether low serum 25(OH) vitamin D concentrations are associated with a higher risk for hip fractures in community-dwelling women and whether this relationship may be mediated by poor physical functioning, frailty, falls, sex-steroid hormones, renal function, or bone turnover. Methods Study Population Our study population came from the WHI-OS, a prospective cohort study that enrolled 93676 women between 1994 and 1998 at 40 U.S. clinical centers (age range, 50 to 79 years). Study methods are described in detail elsewhere (17). In brief, women were eligible if they were postmenopausal, were unlikely to move or die within 3 years, were not enrolled in the WHI clinical trials, and were not currently participating in any other clinical trial. The human subjects review committees from each participating institution approved the study. Follow-up and Outcome Ascertainment We sent women questionnaires annually to report any hospitalization and other outcomes, including fractures. As of August 2004, median follow-up duration was 7.1 years (range, 0.7 to 9.3 years). At that time, 3.7% of participants had withdrawn or were lost to follow-up and 5.3% had died. We reviewed medical records to verify cases of hip fracture, and blinded central adjudicators confirmed the cases (18). We excluded patients with pathologic hip fractures. Nested CaseControl Study Design The present study is a casecontrol study nested within the prospective design of WHI-OS. We excluded women who had a history of hip fracture; were receiving hormone therapy up to 1 year before enrollment; or were currently receiving androgens, selective estrogen receptor modulators, antiestrogens, or other osteoporosis treatments (bisphosphonates, calcitonin, or parathyroid hormone). We also excluded women with insufficient serum stored or of unknown ethnicity, leaving 39793 eligible participants. Of these, 404 women had a hip fracture. We randomly selected 400 of these women to form the incident hip fracture group. For each case-patient, we selected 1 control participant who was within 1 year of the case-patients age at screening, was of matching race or ethnicity, and had their blood drawn within 120 days of the case-patients blood draw date; 99% of case-patients and control participants were matched within 30 days. Baseline Clinical Variables We divided clinical centers into 3 geographic regions on the basis of latitude: northern (>40 N), middle (35 to 40 N), and southern (<35 N). We ascertained all covariates at baseline. Clinic interviewers recorded current use of prescription medications by direct inspection of medicine containers. We entered prescription names into the WHI database and assigned drug codes by using Medispan software (First DataBank, San Bruno, California). Average amounts of elemental calcium and vitamin D preparations were entered directly from supplement containers. Dietary intakes of calcium and vitamin D were assessed by using a semiquantitative food-frequency questionnaire (19). Total calcium and vitamin D intake was defined as the sum of diet and supplements. We used questionnaires to ascertain date of birth, race or ethnicity, age at menopause, history of any fracture after age 55 years, smoking, parental history of hip fracture, self-rated health status, and alcohol consumption. We classfied physical activity on the basis of frequency and duration of walking and mild, moderate, and strenuous activities in the previous week. We calculated kilocalories of energy expended in 1 week as the metabolic equivalent (kcal hours/week per kg) (20). We measured physical function by using the RAND Short Form-36 physical function scale, which comprises 10 items measuring whether health now limits physical function in moderate or vigorous activity (2 items); strength to lift, carry, stoop, bend, or stair climb (4 items); ability to walk various distances without difficulty (3 items); and self-care (1 item) (21). The scale is scored from 0 to 100, with higher scores indicating better physical function. We compared women with a score greater than 90 versus those with a score less than or equal to 90, a cutoff value corresponding to the median score. We computed a frailty score, which included self-reported muscle weakness and impaired walking speed (RAND Short Form-36 physical function scale score <75), exhaustion (RAND Short Form-36 vitality scale score <55), low physical activity (lowest quartile of physical activity), and unintended weight loss between baseline and 3 years of follow-up (22). A woman was considered frail if she reported 3 or more of these indicators. Weight was measured on a balance-beam scale with the participant dressed in indoor clothing without shoes. Height was measured by using a wall-mounted stadiometer. Body mass index was calculated as weight (in kg) divided by height (in m2). Laboratory Procedures Laboratory personnel blinded to casecontrol status obtained a 12-hour fasting blood sample at the baseline visit, which was processed and stored at 80C according to strict quality control procedures (23). Serum 25(OH) vitamin D concentrations and sex-steroid hormone levels were measured at the Reproductive Endocrine Research Laboratory at the University of Southern California. 25-Hydroxyvitamin vitamin D was measured by using a radioimmunoassay with DiaSorin reagents (DiaSorin, Stillwater, Minnesota). The sensitivity of the assay was 3.75 nmol/L. The interassay coefficients of variation were 11.7%, 10.5%, 8.6%, and 12.5% at 14.0, 56.8, 82.5, and 122.5 nmol/L, respectively. Estradiol and testosterone concentrations were quantified by using sensitive and specific radioimmunoassays after organic solvent extraction and celite column partition chromatography (2427). The intra- and interassay coefficients of variation were 7.9% and 8% to 12%, respectively, for estradiol and 6% and 10% to 12%, respectively, for testosterone. We calculated bioavailable hormone concentrations by using mass action equations (2830). We measured sex hormonebinding globulin by using a solid-phase, 2-site chemiluminescent immunoassay. The intra- and interassay coefficients of variation were 4.1% to 7.7% and 5.8% to 13%, respectively. Serum cystatin C, a marker of renal function that is independent of age and weight, was measured at Medical Research Laboratories International, Highland Heights, Kentucky, by using the Dade Behring BN-II nephelometer and Dade Behring reagents (Dade Behring, Ramsey, Minnesota) in a particle-enhanced immunonepholometric assay. Serum C-terminal telopeptide of type I collagen and aminoterminal procollagen extensions propeptide were measured by immunoassay (Synarc, Lyon, France). Statistical Analysis We used chi-square and t tests to compare baseline characteristics between case-patients with hip fracture and matched control participants. We assigned 25(OH) vitamin D concentrations to quartile categories defined on the basis of the distribution in the control participants. To further assess confounding, we compared baseline characteristics across quartiles of 25(OH) vitamin D concentrations in case-patients and control participants combined. We calculated the P values for trend by using logistic regression and coding the variable of interest as a continuous variable. We assessed the association between serum 25(OH) vitamin D concentrations and incident hip fracture in conditional logistic regression models that retained the matched casecontrol design. We first examined the unadjusted associations and then adjusted for age, b


Journal of Clinical Oncology | 2003

Adiposity and Sex Hormones in Postmenopausal Breast Cancer Survivors

Anne McTiernan; Kumar B. Rajan; Shelley S. Tworoger; Melinda L. Irwin; Leslie Bernstein; Richard Baumgartner; Frank D. Gilliland; Frank Z. Stanczyk; Yutaka Yasui; Rachel Ballard-Barbash

PURPOSE Overweight and obese women with breast cancer have poorer survival compared with thinner women. One possible reason is that breast cancer survivors with higher degrees of adiposity have higher concentrations of tumor-promoting hormones. This study examined the association between adiposity and concentrations of estrogens, androgens, and sex hormone-binding globulin (SHBG) in a population-based sample of postmenopausal women with breast cancer. METHODS We studied the associations between body mass index (BMI), body fat mass, and percent body fat, measured by dual-energy x-ray absorptiometry scan, waist circumference, and waist-to-hip circumference ratio, with concentrations of estrone, estradiol, testosterone, SHBG, dehydroepiandrosterone sulfate, free estradiol, and free testosterone in 505 postmenopausal women in western Washington and New Mexico with incident stage 0 to IIIA breast cancer. Blood and adiposity measurements were performed between 4 and 12 months after diagnosis. RESULTS Obese women (BMI > or = 30) had 35% higher concentrations of estrone and 130% higher concentrations of estradiol compared with lighter-weight women (BMI < 22.0; P =.005 and.002, respectively). Similar associations were observed for body fat mass, percent body fat, and waist circumference. Testosterone concentrations also increased with increasing levels of adiposity (P =.0001). Concentrations of free estradiol and free testosterone were two to three times greater in overweight and obese women compared with lighter-weight women (P =.0001). CONCLUSION These data provide information about potential hormonal explanations for the association between adiposity and breast cancer prognosis. These sex hormones may be useful biomarkers for weight loss intervention studies in women with breast cancer.


Neurology | 2001

High-dose estradiol improves cognition for women with AD Results of a randomized study

Sanjay Asthana; Laura D. Baker; Suzanne Craft; Frank Z. Stanczyk; Richard C. Veith; Murray A. Raskind; S. R. Plymate

Objective: To characterize the cognitive and neuroendocrine response to treatment with a high dose of estrogen for postmenopausal women with AD. Methods: Twenty postmenopausal women with AD were randomized to receive either 0.10 mg/day of 17β-estradiol by skin patch or a placebo patch for 8 weeks. Subjects were evaluated at baseline, at weeks 3, 5, and 8 during treatment, and again 8 weeks after treatment termination. During each visit, cognition was assessed with a battery of neuropsychological tests, and blood samples were collected to measure plasma estradiol as well as several other neuroendocrine markers of interest. Results: Significant effects of estrogen treatment were observed on attention (Stroop Color Word Interference Test), verbal memory (Buschke Selective Reminding Test), and visual memory (Figure Copy/Memory). In addition, women treated with estrogen demonstrated improved performance on a test of semantic memory (Boston Naming Test) compared with subjects who received a placebo. Estrogen appeared to have a suppressive effect on the insulin-like growth factor (IGF) system such that plasma concentration of IGF binding protein-3 was significantly reduced and plasma levels of estradiol and IGF-I were negatively correlated during estrogen treatment. Conclusions: Administration of a higher dose of estrogen may enhance attention and memory for postmenopausal women with AD. Although these findings provide further clinical evidence to support a cognitive benefit of estrogen for women with AD, studies evaluating the effect of estradiol administration, in particular, using larger sample sizes and for longer treatment durations are warranted before the therapeutic potential of estrogen replacement for women with AD can be firmly established.


The Journal of Neuroscience | 2007

Progesterone and Estrogen Regulate Alzheimer-Like Neuropathology in Female 3xTg-AD Mice

Jenna C. Carroll; Emily R. Rosario; Lilly Chang; Frank Z. Stanczyk; Salvatore Oddo; Frank M. LaFerla; Christian J. Pike

Estrogen depletion in postmenopausal women is a significant risk factor for the development of Alzheimers disease (AD), and estrogen-based hormone therapy may reduce this risk. However, the effects of progesterone both alone and in combination with estrogen on AD neuropathology remain unknown. In this study, we used the triple transgenic mouse model of AD (3xTg-AD) to investigate the individual and combined effects of estrogen and progesterone on β-amyloid (Aβ) accumulation, tau hyperphosphorylation, and hippocampal-dependent behavioral impairments. In gonadally intact female 3xTg-AD mice, AD-like neuropathology was apparent by 3 months of age and progressively increased through age 12 months, a time course that was paralleled by behavioral impairment. Ovariectomy-induced depletion of sex steroid hormones in adult female 3xTg-AD mice significantly increased Aβ accumulation and worsened memory performance. Treatment of ovariectomized 3xTg-AD mice with estrogen, but not progesterone, prevented these effects. When estrogen and progesterone were administered in combination, progesterone blocked the beneficial effect of estrogen on Aβ accumulation but not on behavioral performance. Interestingly, progesterone significantly reduced tau hyperphosphorylation when administered both alone and in combination with estrogen. These results demonstrate that estrogen and progesterone independently and interactively regulate AD-like neuropathology and suggest that an optimized hormone therapy may be useful in reducing the risk of AD in postmenopausal women.


American Journal of Obstetrics and Gynecology | 1992

Behavioral stress responses in premenopausal and postmenopausal women and the effects of estrogen

Steven R. Lindheim; Richard S. Legro; Leslie Bernstein; Frank Z. Stanczyk; Marcela A. Vijod; Steven C. Presser; Rogerio A. Lobo

OBJECTIVE Our purpose was to determine the pattern of reactivity to stress in premenopausal and postmenopausal women and to assess the effects of estrogen. STUDY DESIGN A behavioral stress test was given to premenopausal (n = 13) and postmenopausal women (n = 36). Biophysical and neuroendocrine responses were measured during and on completion of the stress test. The postmenopausal women were then randomized to placebo or transdermal estradiol treatment for 6 weeks, at which time another behavioral stress test was given. RESULTS Stress reactivity to math and speech tasks elicited significantly greater systolic blood pressure responses in postmenopausal women compared with premenopausal women (p < 0.05). On retesting, significant biophysical responses that were present during the initial stress testing were still present (p < 0.05) in the placebo group but were blunted with estrogen treatment. Plasma corticotropin, cortisol, androstenedione, and norepinephrine increased during testing to a similar degree in premenopausal and postmenopausal women; this response was maintained after placebo treatment. Postmenopausal women treated with estrogen had blunted responses. CONCLUSION Significant differences in responses to psychologic stress exist in premenopausal and postmenopausal women. The lack of adaptation may account in part for the increased risk of cardiovascular disease in postmenopausal women. Estrogen appears to blunt the stress-induced response.


Obesity | 2006

Relation of BMI and Physical Activity to Sex Hormones in Postmenopausal Women

Anne McTiernan; Lie Ling Wu; Chu Chen; Rowan T. Chlebowski; Yasmin Mossavar-Rahmani; Francesmary Modugno; Michael G. Perri; Frank Z. Stanczyk; Linda Van Horn; Ching-Yun Wang

Objective: Levels of estrogen, androgen, and prolactin have been related to risk of postmenopausal breast cancer. However, the determinants of these hormone concentrations are not established. The purpose of this study was to examine correlates of endogenous sex hormones.


The Journal of Urology | 2002

BODY SIZE AND SERUM LEVELS OF INSULIN AND LEPTIN IN RELATION TO THE RISK OF BENIGN PROSTATIC HYPERPLASIA

Sara E. Dahle; Chokkalingam Ap; Yu-Tang Gao; Jie Deng; Frank Z. Stanczyk; Ann W. Hsing

PURPOSE Obesity has been implicated in the etiology of benign and malignant prostatic growth due to its influence on metabolic and endocrine changes. Because obesity is an important determinant of serum levels of insulin and leptin (the product of the obesity gene Ob), we investigated the role of obesity and serum levels of insulin and leptin in benign prostatic hyperplasia (BPH) etiology. MATERIALS AND METHODS Fasting serum levels of insulin and leptin as well as the body mass index, a measure of overall obesity, and waist-to-hip ratio, an indicator of abdominal obesity, were determined in 200 men newly diagnosed with BPH who were hospitalized for surgery and in 302 randomly selected healthy male subjects from the population in Shanghai, China. RESULTS A higher waist-to-hip ratio and higher serum insulin were significantly associated with an increased risk of BPH. Relative to men in the lowest waist-to-hip ratio quartile (less than 0.856) those in the highest quartile (greater than 0.923) were at 2.4-fold risk (odds ratio 2.42, 95% confidence interval [CI] 1.34 to 4.37, test for trend p = 0.01). Similarly relative to men in the lowest quartile of insulin (less than 5.87 microU. per ml.) those in the highest quartile (greater than 9.76 microU. per ml.) were at significantly increased risk (odds ratio 2.47, 95% CI 1.35 to 4.54, test for trend p = 0.009). The effect of insulin on BPH risk was more pronounced in men in low and middle tertiles of the waist-to-hip ratio (odds ratios comparing high to low insulin tertiles 2.8 and 2.7, respectively), while among men in the highest waist-to-hip ratio tertile insulin was not significantly associated with BPH risk. In contrast, we found no significant odds ratio comparing the highest to lowest quartiles of leptin (odds ratio 0.62, 95% CI 0.33 to 1.17) or body mass index (odds ratio 1.64, 95% CI 0.96 to 2.81). CONCLUSIONS Our results suggest that abdominal obesity and increasing serum insulin, and possibly overall obesity but not serum leptin are associated with a higher risk of BPH. Further prospective and laboratory studies are needed to confirm these results and elucidate the underlying mechanisms.

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Richard J. Paulson

University of Southern California

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Rogerio A. Lobo

University of Southern California

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Lilly Chang

University of Southern California

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Anne McTiernan

University of Washington

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Daniel R. Mishell

University of Southern California

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Elisabet Gentzschein

University of Southern California

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Malcolm C. Pike

Memorial Sloan Kettering Cancer Center

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Wendy J. Mack

University of Southern California

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Howard N. Hodis

University of Southern California

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