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Languages : en
Pages : 177
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Book Description
Only 25--50% of people produce the daidzein-metabolite equol after eating soy. Equol is more bioavailable to breast tissues and may have more potent anti-cancer effects than other soy isoflavones. Thus any association between soy intake and risk of breast cancer may be modified by inter-individual differences in equol production. This is a cross-sectional study of the associations between equol status, intake of soy foods, and mammographic density in a sample of postmenopausal women recruited at a radiology clinic in Western New York. Participants reported at least one year since the last menses, were over 45 years of age (or>51 years, if they reported menopause due to hysterectomy and at least one remaining ovary), had no history of cancer or breast augmentation/reduction surgery, and no current hormone use. Percent density (PD) was measured using computer-assisted analysis of digitized images of retrieved cranio-caudal films. Equol status was assessed using a soy-challenge protocol; usual soy intake was assessed using a questionnaire. General linear models were used to assess independent and joint effects of equol status and regular intake of soy foods on PD. Of 325 enrolled, 248 participants (76%) completed all study assessments and are included in the present analysis. Mean PD was 34% ("18). Seventy-one participants (29%) were classified as equol producers. Forty-three participants (17%) reported regularly eating at least one soy food weekly. There were no significant independent associations of soy status or soy intake with PD, but there was a significant interaction between these factors (p=0.02) in determining PD. Among equol producers, those with weekly intake of soy foods had lower PD (39.4% in weekly consumers of soy vs. 29.6% in non-consumers after adjusting for age and BMI, p for difference=0.06); in contrast, among non-producers of equol, weekly soy intake was associated with higher PD (36.4% in weekly soy consumers vs. 31.0% in non-consumers, after adjustment, p for difference=0.07). Our results suggest that equol producers and non-producers may experience different effects of exposure to dietary soy on breast tissue and perhaps, also on breast cancer risk. Further research will be needed to understand the nature of these associations, and whether they represent causal or non-causal relationships. Secondary analyses explored associations of dietary macronutrients with mammographic density, and a novel finding that equol status is associated with history of hormone use.
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 177
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Book Description
Only 25--50% of people produce the daidzein-metabolite equol after eating soy. Equol is more bioavailable to breast tissues and may have more potent anti-cancer effects than other soy isoflavones. Thus any association between soy intake and risk of breast cancer may be modified by inter-individual differences in equol production. This is a cross-sectional study of the associations between equol status, intake of soy foods, and mammographic density in a sample of postmenopausal women recruited at a radiology clinic in Western New York. Participants reported at least one year since the last menses, were over 45 years of age (or>51 years, if they reported menopause due to hysterectomy and at least one remaining ovary), had no history of cancer or breast augmentation/reduction surgery, and no current hormone use. Percent density (PD) was measured using computer-assisted analysis of digitized images of retrieved cranio-caudal films. Equol status was assessed using a soy-challenge protocol; usual soy intake was assessed using a questionnaire. General linear models were used to assess independent and joint effects of equol status and regular intake of soy foods on PD. Of 325 enrolled, 248 participants (76%) completed all study assessments and are included in the present analysis. Mean PD was 34% ("18). Seventy-one participants (29%) were classified as equol producers. Forty-three participants (17%) reported regularly eating at least one soy food weekly. There were no significant independent associations of soy status or soy intake with PD, but there was a significant interaction between these factors (p=0.02) in determining PD. Among equol producers, those with weekly intake of soy foods had lower PD (39.4% in weekly consumers of soy vs. 29.6% in non-consumers after adjusting for age and BMI, p for difference=0.06); in contrast, among non-producers of equol, weekly soy intake was associated with higher PD (36.4% in weekly soy consumers vs. 31.0% in non-consumers, after adjustment, p for difference=0.07). Our results suggest that equol producers and non-producers may experience different effects of exposure to dietary soy on breast tissue and perhaps, also on breast cancer risk. Further research will be needed to understand the nature of these associations, and whether they represent causal or non-causal relationships. Secondary analyses explored associations of dietary macronutrients with mammographic density, and a novel finding that equol status is associated with history of hormone use.
Author: Barbara Elizabeth Teter
Publisher:
ISBN: 9780542999703
Category :
Languages : en
Pages : 189
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Background. Mammographic breast density (MBD) is a widely recognized surrogate marker of breast cancer risk and serves as the main dependent variable in our study. Epidemiologic evidence indicates that risk factors shared by breast cancer and mammographic breast density are also factors related to endogenous pineal melatonin which serves as the main independent variable. Experimental studies have consistently demonstrated anticarcinogenic, antiproliferative, antioxidant, and immunostimulating properties of endogenous melatonin. In epidemiologic studies that have investigated the role of melatonin deficiency in the etiology of breast cancer results are not consistent. It has also been reported that women who take aspirin have a lower risk of developing breast cancer but study results vary markedly. Aspirin use serves as our main independent variable in our secondary study of aspirin use and mammographic breast density. Objectives. We examined whether mammographic breast density would be inversely related to nocturnal endogenous melatonin and in a secondary analysis whether inversely related to aspirin use. Design. We recruited 293 postmenopausal women with appointments for screening mammograms at a large western New York state radiological clinic from March 2005 through August 2005 to conduct our cross-sectional study. Screening mammograms were taken during clinic visits and mammographic breast density was measured from digitized images utilizing a validated computer-assisted method. The main metabolite of endogenous melatonin, 6-sulfatoxymelatonin, was measured by radioimmunoassay from overnight urine samples and creatinine-adjusted. Aspirin use and covariate data were collected from interviews, questionnaires, and anthropometric measures taken during clinic visits. Results. The mean age was 58 (SD 6.0), 30% had BMI (kg/m2) classified as obese, and 15% of the women were nulliparous. In a general linear model we observed a marginally significant trend (p 0.04) for categorical melatonin inversely related to percentage mammographic density adjusted for age, BMI, number of full-term pregnancies, and past use of combination hormone replacement therapy. Stratified analysis of aspirin use and non-use yielded a 10% reduction in percentage mammographic density among nulliparous women in the aspirin group (adjusted mean percent density 32.7, 95% CI: 29.9-3.61) compared to non-aspirin users (mean 43.4, 95% CI: 36.7-50.2). Conclusions. The results of this study suggest that nocturnal melatonin secretion may be associated with traditional breast cancer risk factors such as mammographic density, age, BMI, and parity. Aspirin use appeared to be related to lower breast density in postmenopausal women who are nulliparous. The potential to reduce breast cancer risk through lifestyle habits such as the use of aspirin or to minimize the influence of modern disruption of endogenous melatonin warrants further study.
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Category :
Languages : en
Pages : 13
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Hormone Replacement Therapy (HRT) has been shown to increase breast cancer risk as well as to increase breast density. Breast density, a reflection of the histologic composition of the breast, is one factor shown to affect mammographic sensitivity and specificity, and it is predictive of breast cancer risk. Thus, the use of HRT, through its effect on breast density, may compromise the well-established reduction in mortality gained by mammographic screening. However, not all women on HRT will experience an increase in breast density. We propose a novel hypothesis to explain in part the individual variability in breast density seen among women on HRT: differences in breast density are associated with differences in estrogen metabolism, and this association may be attenuated by individual factors such as body mass index and HRT regimen. Our work and the work of others provide compelling evidence to support this hypothesis. To date 50 cases and 180 healthy postmenopausal women have been enrolled in this study.
Author: Cameron B. Haas
Publisher:
ISBN:
Category :
Languages : en
Pages : 82
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In this work we leveraged genomic information from large-scale population-based studies to explore the relationships between three epidemiologic factors associated with breast cancer in women: 1) mammographic density, 2) sex hormone concentrations, and 3) body mass index (BMI). Mammographic density, which describes the proportion of dense (i.e., epithelial and stromal) tissue in the breast, is one of the strongest predictors of breast cancer in women. Women with extremely dense breasts have a 3 to 6-fold increased risk of breast cancer compared to those with primarily fatty breasts. Breast cancer is generally considered to be a primarily hormone-driven cancer, an attribute that has led to the development of effective treatment and prophylactic strategies for hormone receptor positive subtypes and cause for investigating the role of endogenous hormones in breast cancer etiology. Finally, BMI has been consistently observed to have paradoxical associations with breast cancer across menopause, with evidence of preventative effects associated with higher BMI in premenopausal women but increased risk in postmenopausal women. We first built on recent analyses that investigated the genetic architecture of testosterone and sex hormone binding globulin (SHBG) in men and women of European ancestry by conducting genome-wide association studies (GWAS) of estradiol concentrations in women. Additionally, we investigated the generalizability of previous findings in women of African ancestry. We further conducted menopausal status specific GWAS of these sex hormones to identify loci with heterogeneous effects across menopause. We found that the strongest overall genetic predictor of testosterone concentrations, located in the CYP3A7 gene, had an effect nearly twice as large in premenopausal women compared to postmenopausal women. Similarly, genetic variants in the AKR1C4 gene were strongly associated with concentrations of SHBG in premenopausal women, but not in postmenopausal women, with a 5-fold difference in effect estimates between the two. We also estimated the shared heritability across menopausal status specific hormone concentrations, and observed a relatively low genetic correlation between pre- and postmenopausal detectable levels of estradiol, whereas comparisons of pre- and postmenopausal shared heritability for SHBG and testosterone were both close to one, indicating near identical genetic architectures. We performed gene-level tests for enrichment of genetic associations within tissue-specific gene expressions by collapsing multiple SNP-level associations in a gene while accounting for linkage disequilibrium. Using this gene-set analysis for tissue specificity we observed a change from strong adrenal gland tissue specificity of testosterone in premenopausal to adipose tissue specificity in postmenopausal women, suggesting that adiposity may play a more important role in determining circulating concentrations of testosterone after menopause. To understand the directional relationships between overall and menopausal status specific concentrations of sex hormones and BMI on mammographic dense and non-dense area we performed Mendelian Randomization analyses. We created menopausal status specific genetic instruments for SHBG, testosterone, and estradiol based on our previous work. We obtained single nucleotide polymorphisms (SNP)-specific association statistics from a recent GWAS of mammographic density of up to 27,900 women of European ancestry. Effect estimates for BMI were obtained from the largest meta-GWAS of BMI to date, comprising more than 700,000 individuals. We observed an inverse relationship between overall genetically predicted testosterone and dense area. Increasing genetically predicted BMI was strongly associated with an increase in genetically predicted non-dense area, as previously observed. However, we also observed an inverse association between genetically predicted BMI and absolute dense area, which might explain some of the reduced risk of breast cancer associated with an increase in genetically predicted BMI. Higher genetically predicted BMI was also strongly associated with decreasing SHBG concentrations, as well as increasing concentrations of testosterone. Based on the inverse-variance weighted results, we observed increasing genetically predicted BMI to be associated with a decrease in genetically predicted detectable levels of overall and premenopausal specific estradiol concentrations, but not for postmenopausal only. Multivariable MR approaches for the association of BMI and mammographic density adjusting for sex hormones did not substantively change the effect estimates of BMI. Building on the strong association between BMI and mammographic density, we sought to identify genetic loci that interact with BMI to alter mammographic density phenotypes. We conducted genome-wide tests for the interaction between SNPs and BMI on percent mammographic density, absolute dense area, and absolute non-dense area in 14,837 women. Despite having the largest sample size to date with genetic and phenotypic data for mammographic density, we did not find any loci that reached standard Bonferroni correction for statistical significance. This work presents novel findings of the unique genetic architectures of menopausal specific concentrations of sex hormones in women and extends these findings to investigate their associations with mammographic density. We show that BMI plays an important role in determining not only non-dense area, but also dense area and a possibly separate mechanism for breast cancer etiology. Additionally, there is evidence based on our MR approaches of a regulatory role of BMI on endogenous estradiol as yet another possible pathway to tumorigenesis. We did not identify any genetic variant that has a strong modifying effect of BMI on mammographic density phenotypes. It is possible that larger studies are merited to investigate the interactions between germline genetic variants and BMI on mammographic density variation.
Author: Caroline J. Hollins Martin
Publisher: Springer Science & Business Media
ISBN: 1627033734
Category : Medical
Languages : en
Pages : 474
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Book Description
Nutrition and Diet in Menopause is a single comprehensive source that will provide readers with an understanding of menopause. Holistic in its approach, this volume is divided into five sections covering psychological, endocrine and lifestyle factors, metabolism and physiology, bone and nutrition, cancer and nutrition, cardiovascular factors and dietary supplements in menopause. In-depth chapters review the potential long term consequences of menopause on the overall health of women, not only at the physical level including hot flushes (flashes) , alterations to the genitourinary system, skin changes, decreased cardiovascular functions, hypertension, headache, back pain, and constipation. Written by international leaders and trendsetters, Nutrition and Diet in Menopause is essential reading for endocrinologists, cardiologists, nutritionists and all health care professionals who are interested in women’s health.
Author: Victor R. Preedy
Publisher: Springer
ISBN: 9789400776920
Category : Medical
Languages : en
Pages : 0
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Book Description
In the past decade there has been a major sea change in the way disease is diagnosed and investigated due to the advent of high throughput technologies, such as microarrays, lab on a chip, proteomics, genomics, lipomics, metabolomics etc. These advances have enabled the discovery of new and novel markers of disease relating to autoimmune disorders, cancers, endocrine diseases, genetic disorders, sensory damage, intestinal diseases etc. In many instances these developments have gone hand in hand with the discovery of biomarkers elucidated via traditional or conventional methods, such as histopathology or clinical biochemistry. Together with microprocessor-based data analysis, advanced statistics and bioinformatics these markers have been used to identify individuals with active disease or pathology as well as those who are refractory or have distinguishing pathologies. New analytical methods that have been used to identify markers of disease and is suggested that there may be as many as 40 different platforms. Unfortunately techniques and methods have not been readily transferable to other disease states and sometimes diagnosis still relies on single analytes rather than a cohort of markers. There is thus a demand for a comprehensive and focused evidenced-based text and scientific literature that addresses these issues. Hence the formulation of Biomarkers in Disease. The series covers a wide number of areas including for example, nutrition, cancer, endocrinology, cardiology, addictions, immunology, birth defects, genetics, and so on. The chapters are written by national or international experts and specialists.
Author: G. Sarwar Gilani
Publisher: The American Oil Chemists Society
ISBN: 9781893997325
Category : Health & Fitness
Languages : en
Pages : 682
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Author: Tommaso Falcone
Publisher: Elsevier Health Sciences
ISBN: 0323033091
Category : Medical
Languages : en
Pages : 846
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Book Description
Clinical Reproductive Medicine and Surgery is the new, definitive resource in reproductive medicine. This unique text offers detailed discussion on both the medical and surgical management of reproductive disorders, as well as coverage of associated imaging modalities. Included are chapters on Reproductive Genetics, Management of Endometriosis (including interventional radiology), Ultrasonography and Sonohysterography, Preservation of Fertility, and Recurrent Pregnancy Loss. The book also features an accompanying DVD with additional images and video loops. A resource every practitioner interested in Reproductive Endocrinology and Infertility needs! Offers detailed discussion of medical and surgical management of reproductive disorders ... No other text offers coverage of both medical and surgical management in one resource. Covers gynecologic disorders that impact fertility--an important aspect of identifying fertility issues, not included in major competition Section on basic reproductive biology ... Not overly detailed -- Written for a clinician to understand how to practice reproductive medicine Section on reproductive imaging ... Unique to this text - includes US and MRI of the reproductive organs Algorithm in each chapter ... 4-color throughout ... Demonstrates the appropriate clinical investigation and management ... Offers attractive layout and best views of surgical procedures Perform reproductive surgery procedures with step-by-step guidance on intrauterine device insertion and laparoscopic surgery with detailed images and videos on the accompanying dvd
Author: Gianni Bonadonna
Publisher: CRC Press
ISBN: 1841844187
Category : Medical
Languages : en
Pages : 426
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Book Description
With the current advances in chemotherapy and hormonal drugs for breast cancer, as well as in surgical techniques and procedures, a revised edition of this popular textbook has become increasingly necessary. Completely overhauling the existing material, the editors of this important work have provided a full update of the area, focusing in particular upon the topics where there has been most progress and controversy.
Author: Juan Francisco Rodríguez-Landa
Publisher: BoD – Books on Demand
ISBN: 9535134051
Category : Health & Fitness
Languages : en
Pages : 138
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Book Description
Menopause is a natural state of development in women, but it is also a period of vulnerability to the development of several disorders, such as vasomotor symptoms, hot flashes, vaginal dryness, osteoporosis, cognitive deterioration, depression, and anxiety. Factors as diverse as culture, diet, exercise, maternity, age, and genetics can influence the severity of symptoms that are experienced during menopause and can modify the response to diverse therapies. Studying menopause from a multidisciplinary perspective will help elucidate the different factors that affect health during this specific stage of a woman's life. This book presents several aspects of menopause, including its evolutionary origins, novel nonhormonal therapies, and the neurobiology of related disorders.
