207 results on '"Helzlsouer, K. J."'
Search Results
52. The practice of prophylactic mastectomy: a survey of Maryland surgeons.
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Houn, F, primary, Helzlsouer, K J, additional, Friedman, N B, additional, and Stefanek, M E, additional
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- 1995
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53. More on Endometrial Cancer and Tamoxifen
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HELZLSOUER, K. J., primary and BUSH, T., additional
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- 1994
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54. Serum Albumin, Bilirubin, and Uric Acid and the Anatomic Site-Specific Incidence of Colon Cancer
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Ko, W.-F., primary, Helzlsouer, K. J., additional, and Comstock, G. W., additional
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- 1994
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55. Markers of Disease
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Helzlsouer, K. J., primary
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- 1993
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56. Reported effects of long-term freezer storage on concentrations of retinol, beta-carotene, and alpha-tocopherol in serum or plasma summarized
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Comstock, G W, primary, Alberg, A J, primary, and Helzlsouer, K J, primary
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- 1993
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57. Prospective study of serum CA-125 levels as markers of ovarian cancer
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Helzlsouer, K. J., primary
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- 1993
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58. Menopausal-type symptoms among breast cancer patients on aromatase inhibitor therapy.
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Gallicchio, L., MacDonald, R., Wood, B., Rushovich, E., and Helzlsouer, K. J.
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BREAST cancer ,MENOPAUSE ,AROMATASE inhibitors ,AROMATASE ,WOMEN'S health ,THERAPEUTICS - Abstract
Objectives To examine self-reported menopausal-type symptoms among breast cancer patients on aromatase inhibitors (AIs) compared to women of the same age who had not been diagnosed with cancer, and to determine whether the percentage of breast cancer patients experiencing these symptoms changed over the first 6 months of AI treatment. Methods Data from a 6-month cohort study of 100 breast cancer patients initiating AI therapy and of 200 women of a similar age without a history of cancer were analyzed. At baseline (prior to the initiation of AI therapy among the breast cancer patients), 3 months, and 6 months, a comprehensive questionnaire was administered to participants that ascertained data on the experiencing of specific menopausal-type symptoms. Results The data showed statistically significant increases in the prevalence of certain symptoms from baseline to either follow-up point among the breast cancer patients; these symptoms included hot flushes, night sweats, pain during intercourse, hair loss, forgetfulness, depression, difficulty falling asleep, and interrupted sleep. Additionally, breast cancer patients were more likely than the women in the comparison group to report the new onset of many of these same symptoms during the follow-up time period. Conclusions Because bothersome symptoms and side-effects are a major reason for discontinuation and non-adherence to treatment, symptoms should be monitored and addressed by oncologists so that the breast cancer patient can maintain her quality of life and remain adherent to the treatment schedule. [ABSTRACT FROM AUTHOR]
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- 2012
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59. Circulating sex hormones and breast cancer risk factors in postmenopausal women: reanalysis of 13 studies.
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Key, T. J., Appleby, P N, Reeves, G K, Roddam, A W, Helzlsouer, K J, Alberg, A J, Rollison, D E, Dorgan, J F, Brinton, L A, Overvad, K, Kaaks, R, Trichopoulou, A, Clavel-Chapelon, F, Panico, S, Duell, E J, Peeters, P H M, Rinaldi, S, Fentiman, I S, Dowsett, M, and Manjer, J
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SEX hormones ,BREAST cancer ,CANCER risk factors ,OVARIECTOMY ,POSTMENOPAUSE ,TESTOSTERONE ,CIGARETTE smokers ,ANDROGENS - Abstract
Background: Breast cancer risk for postmenopausal women is positively associated with circulating concentrations of oestrogens and androgens, but the determinants of these hormones are not well understood.Methods: Cross-sectional analyses of breast cancer risk factors and circulating hormone concentrations in more than 6000 postmenopausal women controls in 13 prospective studies.Results: Concentrations of all hormones were lower in older than younger women, with the largest difference for dehydroepiandrosterone sulphate (DHEAS), whereas sex hormone-binding globulin (SHBG) was higher in the older women. Androgens were lower in women with bilateral ovariectomy than in naturally postmenopausal women, with the largest difference for free testosterone. All hormones were higher in obese than lean women, with the largest difference for free oestradiol, whereas SHBG was lower in obese women. Smokers of 15+ cigarettes per day had higher levels of all hormones than non-smokers, with the largest difference for testosterone. Drinkers of 20+ g alcohol per day had higher levels of all hormones, but lower SHBG, than non-drinkers, with the largest difference for DHEAS. Hormone concentrations were not strongly related to age at menarche, parity, age at first full-term pregnancy or family history of breast cancer.Conclusion: Sex hormone concentrations were strongly associated with several established or suspected risk factors for breast cancer, and may mediate the effects of these factors on breast cancer risk. [ABSTRACT FROM AUTHOR]- Published
- 2011
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60. The Reliability of Nipple Aspirate and Ductal Lavage in Women at Increased Risk for Breast Cancer--a Potential Tool for Breast Cancer Risk Assessment and Biomarker Evaluation.
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Visvanathan, K., Santor, D., Ali, S. Z., Brewster, A., Arnold, A., Armstrong, D. K., Davidson, N. E., and Helzlsouer, K. J.
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The article focuses on a study that evaluates the reliability of nipple aspirate (NAF) and ductal lavage in the assessment of breast cancer risk in women in Baltimore, Maryland. Ductal lavage is a method used to extract sample of epithelial cells from breast ducts. Samples of inadequate cellular material for diagnosis were significantly present in postmenopausal women compared with premenopausal women. The study concluded that the use of ductal lavage is limited by technical challenges.
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- 2007
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61. Selenium, zinc, and prostate cancer.
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Platz, E A and Helzlsouer, K J
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- 2001
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62. Epidemiology, prevention, and early detection of breast cancer.
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Abeloff MD, Alberg, A J, Singh, S, May, J W, and Helzlsouer, K J
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- 2000
63. A prospective study of plasma ascorbic acid concentrations and breast cancer (United States).
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Wu, Kana, Helzlsouer, Kathy, Alberg, Anthony, Comstock, George, Norkus, Edward, Hoffman, Sandra, Wu, K, Helzlsouer, K J, Alberg, A J, Comstock, G W, Norkus, E P, and Hoffman, S C
- Abstract
Objectives: To investigate the association between prediagnostic plasma ascorbic acid concentrations and subsequent breast cancer risk in a nested case-control study.Methods: Female volunteer residents of Washington County, MD, donated 14,625 non-fasting blood samples in 1989. Incident breast cancer cases (n = 115) and controls (n = 115) were matched by age, menopausal status at donation, and date and hour of blood donation.Results: Median ascorbic acid concentrations were similar between cases and controls (1.44 mg/dl vs. 1.39 mg/dl. p = 0.78). There was no evidence for a dose-response relationship between higher plasma ascorbic acid concentrations and breast cancer risk [highest vs. lowest fifths: ORadjusted = 0.90, Ptrend = 0.98).Conclusions: Findings from this prospective study do not suggest a protective association between prediagnostic plasma ascorbic acid concentrations and breast cancer risk in the subsequent 5 years of follow-up. [ABSTRACT FROM AUTHOR]- Published
- 2000
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64. Epidemiology, prevention, and early detection of breast cancer.
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Alberg, A J, Lam, A P, and Helzlsouer, K J
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- 1999
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65. Association between glutathione S-transferase M1, P1, and T1 genetic polymorphisms and development of breast cancer.
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Helzlsouer, K J, Selmin, O, Huang, H Y, Strickland, P T, Hoffman, S, Alberg, A J, Watson, M, Comstock, G W, and Bell, D
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BREAST tumors , *COMPARATIVE studies , *DNA , *DNA probes , *GENETIC polymorphisms , *RESEARCH methodology , *MEDICAL cooperation , *PAIRED comparisons (Mathematics) , *RESEARCH , *TRANSFERASES , *PERIMENOPAUSE , *LOGISTIC regression analysis , *EVALUATION research , *RELATIVE medical risk , *CASE-control method , *POSTMENOPAUSE , *ODDS ratio - Abstract
Background: Glutathione S-transferases (GSTs) are encoded by a superfamily of genes and play a role in the detoxification of potential carcinogens. In a nested case-control study, we investigated associations between genetic variability in specific GST genes (GSTM1, GSTT1, and GSTP1) and susceptibility to breast cancer.Methods: In 1989, a total of 32 898 individuals donated blood samples to a research specimen bank established in Washington County, MD. Genotypes of blood specimen DNA were determined for 110 of 115 women with incident cases of breast cancer diagnosed during the period from 1990 through 1995 and up to 113 of 115 control subjects. Associations between specific genotypes and the development of breast cancer were examined by use of logistic regression to calculate odds ratios (ORs) and 95% confidence intervals (CIs).Results: The GSTM1 homozygous null genotype was associated with an increased risk of developing breast cancer (OR = 2.10; 95% CI = 1.22-3.64), principally due to an association with postmenopausal breast cancer (OR = 2.50; 95% CI = 1.34-4.65). For GSTP1, the data were suggestive of a trend of increasing risk with higher numbers of codon 105 valine alleles (compared with isoleucine alleles); a 1.97-fold increased risk of breast cancer (95% CI = 0.77-5.02) was associated with valine/valine homozygosity. The risk of breast cancer associated with the GSTT1 homozygous null genotype was 1.50 (95 % CI = 0.76-2.95). The risk of breast cancer increased as the number of putative high-risk genotypes increased (P for trend <.001) (OR = 3.77; 95% CI = 1.10-12.88 for a combined genotype of GSTM1 null, GSTT1 null, and either GSTP1 valine heterozygosity or GSTP1 valine homozygosity).Conclusions: Our findings suggest that genetic variability in members of the GST gene family may be associated with an increased susceptibility to breast cancer. [ABSTRACT FROM AUTHOR]- Published
- 1998
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66. Epidemiology, prevention, and early detection of breast cancer.
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Alberg AJ, Visvanathan K, Helzlsouer KJ, Alberg, A J, Visvanathan, K, and Helzlsouer, K J
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- 1998
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67. Epidemiology, prevention, and early detection of breast cancer.
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Alberg AJ, Helzlsouer KJ, Alberg, A J, and Helzlsouer, K J
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- 1997
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68. Epidemiology, prevention, and early detection of breast cancer.
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Daudt, Alexander, Alberg, Anthony J., Helzlsouer, Kathy J., Daudt, A, Alberg, A J, and Helzlsouer, K J
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- 1996
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69. Epidemiology, prevention, and early detection of breast cancer.
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Helzlsouer, K J
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- 1995
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70. Epidemiology, prevention, and early detection of breast cancer.
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Helzlsouer KJ and Helzlsouer, K J
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- 1994
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71. Epidemiology, early detection, and prevention of breast cancer.
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Helzlsouer KJ and Helzlsouer, K J
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- 1993
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72. COMT genotype, micronutrients in the folate metabolic pathway and breast cancer risk.
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Goodman, J E, Lavigne, J A, Wu, K, Helzlsouer, K J, Strickland, P T, Selhub, J, and Yager, J D
- Abstract
Catechol-O-methyltransferase (COMT) catalyzes the O-methylation of catechol estrogens (CEs), using S-adenosylmethionine (SAM) as a methyl donor. Several studies have indicated that the val108met COMT polymorphism, which results in a 3-4-fold decrease in activity, is associated with increased breast cancer risk. Folate, whose intake levels have also been associated with breast cancer risk, and other micronutrients in the folate metabolic pathway influence levels of SAM and S-adenosylhomocysteine (SAH), a COMT inhibitor generated by the demethylation of SAM. Because these micronutrients have been shown to alter SAM and SAH levels, we hypothesized that they could also affect COMT-catalyzed CE methylation. Although measurements of SAM and SAH were not initially collected, a secondary analysis of data from two nested case-control studies was performed to examine whether serum levels of folate, vitamin B12 (B12), pyridoxal 5'-phosphate (PLP), cysteine and homocysteine, in conjunction with COMT genotype, were associated with breast cancer risk. COMT(HH) (high activity COMT homozygote) breast cancer cases had statistically significantly lower levels of homocysteine (P = 0.05) and cysteine (P = 0.04) and higher levels of PLP (P = 0.02) than COMT(HH) controls. In contrast, COMT(LL) (low activity COMT homozygote) cases had higher levels of homocysteine than COMT(LL) controls (P = 0.05). No associations were seen between B12, COMT genotype, and breast cancer risk. An increasing number of COMT(L) alleles was significantly associated with increased breast cancer risk in women with below median levels of folate (P(trend) = 0.05) or above median levels of homocysteine (P(trend) = 0.02). These findings are consistent with a role for certain folate pathway micronutrients in mediating the association between COMT genotype and breast cancer risk.
- Published
- 2001
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73. Colon cancer and serum vitamin D metabolite levels 10-17 years prior to diagnosis.
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Braun, M M, Helzlsouer, K J, Hollis, B W, and Comstock, G W
- Abstract
This study examines the hypothesis that low serum levels of vitamin D metabolites are associated with an increased risk for colon cancer. From August through November 1974, 20,305 residents of Washington County, Maryland, donated blood for storage at -70 degrees C in a serum bank. Colon cancer was subsequently diagnosed among 57 of these residents during the period 1984-1991. Controls had donated blood in 1974 and remained free of colon cancer through the date of diagnosis of the case. Two controls were matched to each case on age (+/- 1 year), race, sex, and date of blood draw (+/- 1 month). Mean 25-hydroxyvitamin D levels were 23.6 ng/ml and 23.2 ng/ml, and mean 1,25-dihydroxyvitamin D levels were 34.7 pg/ml and 34.6 pg/ml, in cases and controls, respectively. Analysis by quintile of serum level similarly found that none of the 95% confidence intervals of the odds ratios excluded unity, and a dose-response effect was not observed. Our data provide no strong support for the hypothesis that vitamin D metabolite levels affect the subsequent risk for colon cancer.
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- 1995
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74. The Washington County Training Center: an exemplar of public health research in the field.
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Comstock, G W, Bush, T L, Helzlsouer, K J, and Hoffman, S C
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- 1991
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75. System delay in breast cancer in whites and blacks.
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Caplan, L S, Helzlsouer, K J, Shapiro, S, Freedman, L S, Coates, R J, and Edwards, B K
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Survival differences have been noted between black women and white women with breast cancer. It is hypothesized that a prolonged interval between initial medical consultation and establishment of a diagnosis (system delay), resulting in a more advanced stage of disease at diagnosis, might explain part of this survival difference. This study was performed to determine whether system delay differs between black and white breast cancer patients, and to examine predictors of delay in blacks and whites. The study population consisted of 996 female breast cancer patients from the National Cancer Institute's Black/White Cancer Survival Study, a cohort study carried out in 1985-1986 in the metropolitan areas of Atlanta, Georgia, New Orleans, Louisiana, and San Francisco/Oakland, California. The median system delay was slightly longer for blacks than for whites--2.7 weeks versus 2.1 weeks--but this difference was not statistically significant. Having a palpable lump at diagnosis was associated with reduced system delay in both races, while use of a public clinic increased system delay for blacks. Older women were less likely to be subject to longer system delay than younger women, and this effect was somewhat more pronounced in whites. Survival differences between blacks and whites are probably not due to differences in system delay. However, many women had delays of at least 3 months. Given that younger age and the absence of a palpable lump were the factors most predictive of significant system delay, interventions should be targeted specifically toward reducing system delay in younger women who present without the classical painless lump.
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- 1995
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76. Racial differences in intraocular tension and glaucoma surgery.
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Coulehan, J L, Helzlsouer, K J, Rogers, K D, and Brown, S I
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A total of 4678 persons participated in an Allegheny County, Pennsylvania glaucoma screening program in 1977. Black participants had higher mean intraocular pressures, more frequent pathologic disc changes and more new cases of glaucoma discovered than a sample of white participants matched for sex and age. The same year, in a younger population of 2127 health center employees, the higher prevalence of pathologic disc changes was confirmed, although differences in mean intraocular pressures were variable. Blacks accounted for 23% of hospitalizations for chronic open-angle glaucoma during a three-year period (1975-1977) in 10 Pennsylvania counties, rather than the expected 6.3%. Among those hospitalized for open-angle glaucoma or having anterior chamber surgery, blacks were younger than whites.
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- 1980
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77. Oltipraz chemoprevention trial in Qidong, People's Republic of China: Modulation of serum aflatoxin albumin adduct biomarkers
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Kensler, T. W., He, X., Otieno, M., Egner, P. A., Jacobson, L. P., Chen, B., Wang, J. -S, Zhu, Y. -R, Zhang, B. -C, Wang, J. -B, Wu, Y., Zhang, Q. -N, Qian, G. -S, Kuang, S. -Y, Fang, X., Li, Y. -F, Yu, L. -Y, Prochaska, H. J., Davidson, N. E., Gordon, G. B., Gorman, M. B., Zarba, A., Enger, C., Muñoz, A., Helzlsouer, K. J., and John Groopman
78. Severe metabolic complications in a cross-country runner with sickle cell trait
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Helzlsouer, K. J., primary
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- 1983
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79. DNA repair proficiency: potential susceptiblity factor for breast cancer.
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Helzlsouer KJ, Harris EL, Parshad R, Perry HR, Price FM, Sanford KK, Helzlsouer, K J, Harris, E L, Parshad, R, Perry, H R, Price, F M, and Sanford, K K
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- 1996
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80. Prediagnostic serum levels of carotenoids and vitamin E as related to subsequent cancer in Washington County, Maryland
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Comstock, G. W., Bush, T. L., and Helzlsouer, K. J.
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CANCER ,VITAMIN E - Published
- 1991
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81. Nitrates in Drinking Water and NonHodgkin's Lymphoma
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Freedman, D M, Cantor, K P, Ward, M H, and Helzlsouer, K J
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- 1998
82. Steroid hormone measurements from different types of assays in relation to body mass index and breast cancer risk in postmenopausal women: Reanalysis of eighteen prospective studies.
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Key TJ, Appleby PN, Reeves GK, Travis RC, Brinton LA, Helzlsouer KJ, Dorgan JF, Gapstur SM, Gaudet MM, Kaaks R, Riboli E, Rinaldi S, Manjer J, Hallmans G, Giles GG, Le Marchand L, Kolonel LN, Henderson BE, Tworoger SS, Hankinson SE, Zeleniuch-Jacquotte A, Koenig K, Krogh V, Sieri S, Muti P, Ziegler RG, Schairer C, Fuhrman BJ, Barrett-Connor E, Laughlin GA, Grant EJ, Cologne J, Ohishi W, Hida A, Cauley JA, Fourkala EO, Menon U, Rohan TE, Strickler HD, and Gunter MJ
- Subjects
- Female, Humans, Prospective Studies, Risk Factors, Body Mass Index, Breast Neoplasms etiology, Estradiol blood, Estrone blood, Postmenopause blood, Testosterone blood
- Abstract
Epidemiological studies have examined breast cancer risk in relation to sex hormone concentrations measured by different methods: "extraction" immunoassays (with prior purification by organic solvent extraction, with or without column chromatography), "direct" immunoassays (no prior extraction or column chromatography), and more recently with mass spectrometry-based assays. We describe the associations of estradiol, estrone and testosterone with both body mass index and breast cancer risk in postmenopausal women according to assay method, using data from a collaborative pooled analysis of 18 prospective studies. In general, hormone concentrations were highest in studies that used direct assays and lowest in studies that used mass spectrometry-based assays. Estradiol and estrone were strongly positively associated with body mass index, regardless of the assay method; testosterone was positively associated with body mass index for direct assays, but less clearly for extraction assays, and there were few data for mass spectrometry assays. The correlations of estradiol with body mass index, estrone and testosterone were lower for direct assays than for extraction and mass spectrometry assays, suggesting that the estimates from the direct assays were less precise. For breast cancer risk, all three hormones were strongly positively associated with risk regardless of assay method (except for testosterone by mass spectrometry where there were few data), with no statistically significant differences in the trends, but differences may emerge as new data accumulate. Future epidemiological and clinical research studies should continue to use the most accurate assays that are feasible within the design characteristics of each study., (Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2015
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83. Sex hormones and risk of breast cancer in premenopausal women: a collaborative reanalysis of individual participant data from seven prospective studies.
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Key TJ, Appleby PN, Reeves GK, Travis RC, Alberg AJ, Barricarte A, Berrino F, Krogh V, Sieri S, Brinton LA, Dorgan JF, Dossus L, Dowsett M, Eliassen AH, Fortner RT, Hankinson SE, Helzlsouer KJ, Hoff man-Bolton J, Comstock GW, Kaaks R, Kahle LL, Muti P, Overvad K, Peeters PH, Riboli E, Rinaldi S, Rollison DE, Stanczyk FZ, Trichopoulos D, Tworoger SS, and Vineis P
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- Adult, Body Mass Index, Breast Neoplasms blood, Cooperative Behavior, Dehydroepiandrosterone Sulfate blood, Female, Humans, Prospective Studies, Sex Hormone-Binding Globulin analysis, Breast Neoplasms etiology, Gonadal Steroid Hormones blood, Premenopause
- Abstract
Background: Associations between circulating concentrations of oestrogens, progesterone, and androgens with breast cancer and related risk factors in premenopausal women are not well understood. We aimed to characterise these associations with a pooled analysis of data from seven studies., Methods: Individual participant data for prediagnostic sex hormone and sex hormone-binding globulin (SHBG) concentrations were contributed from seven prospective studies. We restricted analyses to women who were premenopausal and younger than 50 years at blood collection, and to women with breast cancer diagnosed before age 50 years. We estimated odds ratios (ORs) with 95% CIs for breast cancer associated with hormone concentrations by conditional logistic regression in cases and controls matched for age, date of blood collection, and day of cycle, with stratification by study and further adjustment for cycle phase. We examined associations of hormones with risk factors for breast cancer in control women by comparing geometric mean hormone concentrations in categories of these risk factors, adjusted for study, age, phase of menstrual cycle, and body-mass index (BMI). All statistical tests were two-sided., Findings: We included data for up to 767 women with breast cancer and 1699 controls in the risk analyses. Breast cancer risk was associated with a doubling in concentrations of oestradiol (OR 1·19, 95% CI 1·06-1·35), calculated free oestradiol (1·17, 1·03-1·33), oestrone (1·27, 1·05-1·54), androstenedione (1·30, 1·10-1·55), dehydroepiandrosterone sulphate (1·17, 1·04-1·32), testosterone (1·18, 1·03-1·35), and calculated free testosterone (1·08, 0·97-1·21). Breast cancer risk was not associated with luteal phase progesterone (doubling in concentration OR 1·00, 95% CI 0·92-1·09), and adjustment for other factors had little effect on any of these ORs. Cross-sectional analyses in control women showed several associations of sex hormones with breast cancer risk factors., Interpretation: Circulating oestrogens and androgens are positively associated with the risk for breast cancer in premenopausal women., (Copyright © 2013 Endogenous Hormones and Breast Cancer Collaborative Group. Open Access article distributed under the terms of CC BY. Published by Elsevier Ltd. All rights reserved.)
- Published
- 2013
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84. A cross-sectional study of vitamin C and cognitive function in older adults: the differential effects of gender.
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Sato R, Helzlsouer KJ, Comstock GW, Hoffman SC, Norkus EP, and Fried LP
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- Aged, Aging physiology, Cross-Sectional Studies, Female, Health Surveys, Humans, Male, Mental Status Schedule, Nutrition Surveys, Nutritional Requirements, Sex Factors, Surveys and Questionnaires, Ascorbic Acid administration & dosage, Ascorbic Acid blood, Cognition drug effects, Cognition physiology, Diet
- Abstract
Previous studies have suggested that vitamin C status may be associated with cognitive function in community-dwelling populations. However, this has not been consistent across all studies due to methodological differences. This cross-sectional study assessed the association between vitamin C and cognitive function in 544 community-dwelling older adults aged 65 or older who participated in both the Cardiovascular Health Study (CHS) and the CLUE II study in 1989. Three percent of the subjects had low plasma vitamin C concentrations (< 40 mg/dL) and 15% had low total vitamin C intake (< 60 mg/day). Most participants (96.7 percent) had normal cognitive function. In the unadjusted analyses, the highest fifth of plasma vitamin C concentration was associated with better Digit Symbol Substitution Test (DSST) scores and marginally associated with Mini-Mental State Examination (MMSE) compared to the lowest fifth. Total vitamin C intake, measured by Block's food frequency questionnaire, was generally associated with higher MMSE scores, though it was not significant. Adjusting for numerous factors did not substantially change results. In a stratified analysis by gender, higher plasma concentrations or intake were associated with higher MMSE scores for men but not for women. These mixed results do not provide strong evidence of an association between vitamin C concentrations or intake and cognitive function.
- Published
- 2006
85. Differences in ornithine decarboxylase and androgen receptor allele frequencies among ethnic groups.
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O'Brien TG, Guo Y, Visvanathan K, Sciulli J, McLaine M, Helzlsouer KJ, and Watkins-Bruner D
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- Black or African American, Black People, Genetic Predisposition to Disease, Hispanic or Latino, Humans, Male, Risk, White People, Ethnicity genetics, Gene Frequency, Ornithine Decarboxylase genetics, Prostatic Neoplasms genetics, Receptors, Androgen genetics
- Abstract
Recent evidence suggests that the A allele of the ornithine decarboxylase (ODC) gene is a genetic risk factor for prostate cancer. ODC is a target gene of the highly polymorphic androgen receptor (AR) gene, short alleles of which have been associated in some studies with increased prostate cancer risk. We determined ODC allele frequencies and distribution of AR alleles in American Caucasians, African-Americans, Hispanics, Europeans, and Africans. The frequency of the ODC A allele varied from 0.183 (Hispanics, Europeans) to 0.415 (Africans) with American Caucasian and African-Americans having intermediate values. The mean number of CAG repeats in the AR gene varied from 19.8 (African-Americans) to 25.1 (Hispanics). It is possible that ethnic differences in risk alleles for ODC and AR may account for some of the ethnic variation in prostate cancer risk., (Copyright 2004 Wiley-Liss, Inc.)
- Published
- 2004
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86. Body mass index, serum sex hormones, and breast cancer risk in postmenopausal women.
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Key TJ, Appleby PN, Reeves GK, Roddam A, Dorgan JF, Longcope C, Stanczyk FZ, Stephenson HE Jr, Falk RT, Miller R, Schatzkin A, Allen DS, Fentiman IS, Key TJ, Wang DY, Dowsett M, Thomas HV, Hankinson SE, Toniolo P, Akhmedkhanov A, Koenig K, Shore RE, Zeleniuch-Jacquotte A, Berrino F, Muti P, Micheli A, Krogh V, Sieri S, Pala V, Venturelli E, Secreto G, Barrett-Connor E, Laughlin GA, Kabuto M, Akiba S, Stevens RG, Neriishi K, Land CE, Cauley JA, Kuller LH, Cummings SR, Helzlsouer KJ, Alberg AJ, Bush TL, Comstock GW, Gordon GB, Miller SR, and Longcope C
- Subjects
- Aged, Breast Neoplasms blood, Breast Neoplasms pathology, Case-Control Studies, Estradiol blood, Female, Humans, Logistic Models, Middle Aged, Prospective Studies, Risk Assessment, Risk Factors, Body Mass Index, Breast Neoplasms etiology, Gonadal Steroid Hormones blood, Postmenopause
- Abstract
Background: Obesity is associated with increased breast cancer risk among postmenopausal women. We examined whether this association could be explained by the relationship of body mass index (BMI) with serum sex hormone concentrations., Methods: We analyzed individual data from eight prospective studies of postmenopausal women. Data on BMI and prediagnostic estradiol levels were available for 624 case subjects and 1669 control subjects; data on the other sex hormones were available for fewer subjects. The relative risks (RRs) with 95% confidence intervals (CIs) of breast cancer associated with increasing BMI were estimated by conditional logistic regression on case-control sets, matched within each study for age and recruitment date, and adjusted for parity. All statistical tests were two-sided., Results: Breast cancer risk increased with increasing BMI (P(trend) =.002), and this increase in RR was substantially reduced by adjustment for serum estrogen concentrations. Adjusting for free estradiol reduced the RR for breast cancer associated with a 5 kg/m2 increase in BMI from 1.19 (95% CI = 1.05 to 1.34) to 1.02 (95% CI = 0.89 to 1.17). The increased risk was also substantially reduced after adjusting for other estrogens (total estradiol, non-sex hormone-binding globulin-bound estradiol, estrone, and estrone sulfate), and moderately reduced after adjusting for sex hormone-binding globulin, whereas adjustment for the androgens (androstenedione, dehydroepiandrosterone, dehydroepiandrosterone sulfate, and testosterone) had little effect on the excess risk., Conclusion: The results are compatible with the hypothesis that the increase in breast cancer risk with increasing BMI among postmenopausal women is largely the result of the associated increase in estrogens, particularly bioavailable estradiol.
- Published
- 2003
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87. Chlorophyllin intervention reduces aflatoxin-DNA adducts in individuals at high risk for liver cancer.
- Author
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Egner PA, Wang JB, Zhu YR, Zhang BC, Wu Y, Zhang QN, Qian GS, Kuang SY, Gange SJ, Jacobson LP, Helzlsouer KJ, Bailey GS, Groopman JD, and Kensler TW
- Subjects
- Adult, Aflatoxin B1 urine, Aflatoxins urine, Aged, Animals, Biomarkers urine, Carcinoma, Hepatocellular etiology, China, DNA Adducts urine, Female, Food Contamination, Guanine urine, Humans, Liver Neoplasms etiology, Male, Middle Aged, Risk Factors, Aflatoxin B1 analogs & derivatives, Aflatoxins toxicity, Carcinoma, Hepatocellular prevention & control, Chlorophyllides pharmacology, DNA Adducts drug effects, Guanine analogs & derivatives, Liver Neoplasms prevention & control
- Abstract
Residents of Qidong, People's Republic of China, are at high risk for development of hepatocellular carcinoma, in part from consumption of foods contaminated with aflatoxins. Chlorophyllin, a mixture of semisynthetic, water-soluble derivatives of chlorophyll that is used as a food colorant and over-the-counter medicine, has been shown to be an effective inhibitor of aflatoxin hepatocarcinogenesis in animal models by blocking carcinogen bioavailability. In a randomized, double-blind, placebo-controlled chemoprevention trial, we tested whether chlorophyllin could alter the disposition of aflatoxin. One hundred and eighty healthy adults from Qidong were randomly assigned to ingest 100 mg of chlorophyllin or a placebo three times a day for 4 months. The primary endpoint was modulation of levels of aflatoxin-N(7)-guanine adducts in urine samples collected 3 months into the intervention measured by using sequential immunoaffinity chromatography and liquid chromatography-electrospray mass spectrometry. This aflatoxin-DNA adduct excretion product serves as a biomarker of the biologically effective dose of aflatoxin, and elevated levels are associated with increased risk of liver cancer. Adherence to the study protocol was outstanding, and no adverse events were reported. Aflatoxin-N(7)-guanine could be detected in 105 of 169 available samples. Chlorophyllin consumption at each meal led to an overall 55% reduction (P = 0.036) in median urinary levels of this aflatoxin biomarker compared with those taking placebo. Thus, prophylactic interventions with chlorophyllin or supplementation of diets with foods rich in chlorophylls may represent practical means to prevent the development of hepatocellular carcinoma or other environmentally induced cancers.
- Published
- 2001
- Full Text
- View/download PDF
88. Serum dehydroepiandrosterone and dehydroepiandrosterone sulfate and risk of melanoma or squamous cell carcinoma of the skin.
- Author
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Alberg AJ, Gordon GB, Genkinger JM, Hoffman SC, Selvin E, Comstock GW, and Helzlsouer KJ
- Subjects
- Adult, Aged, Carcinoma, Squamous Cell etiology, Case-Control Studies, Female, Humans, Male, Melanoma etiology, Middle Aged, Risk Factors, Skin Neoplasms etiology, Carcinoma, Squamous Cell blood, Dehydroepiandrosterone blood, Dehydroepiandrosterone Sulfate blood, Melanoma blood, Skin Neoplasms blood
- Abstract
Background: Dehydroepiandrosterone (DHEA) and its analogs have potent chemoprotective actions in mouse skin tumorigenesis models. To assess this association in humans, we investigated the relationship of prediagnostic serum concentrations of DHEA and dehydroepiandrosterone sulfate (DHEAS) to the subsequent risk of developing malignant melanoma and squamous cell carcinoma of the skin in residents of Washington County, Maryland, USA., Patients and Methods: In a nested case-control study, serum that had been stored in 1974 was thawed and assayed for DHEA and DHEAS for 23 cases of malignant melanoma and 28 cases of squamous cell carcinoma and 1-2 matched controls per case., Results: The mean serum concentrations of DHEA or DHEAS were similar in cases and controls. There were no statistically significant trends in the risk of developing malignant melanoma or squamous cell skin cancer by concentration of either steroid (all p-for-trends >0.30)., Conclusion: The results of this study do not support the hypothesis that physiological concentrations of DHEA or DHEAS protect against skin cancer in humans.
- Published
- 2001
89. Null association between insulin-like growth factors, insulin-like growth factor-binding proteins, and prostate cancer in a prospective study.
- Author
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Lacey JV Jr, Hsing AW, Fillmore CM, Hoffman S, Helzlsouer KJ, and Comstock GW
- Subjects
- Age Distribution, Aged, Aged, 80 and over, Case-Control Studies, Confidence Intervals, Humans, Incidence, Male, Middle Aged, Odds Ratio, Probability, Prospective Studies, Reference Values, Risk Assessment, Risk Factors, Sensitivity and Specificity, Biomarkers, Tumor analysis, Insulin-Like Growth Factor Binding Protein 3 analysis, Prostatic Neoplasms diagnosis, Prostatic Neoplasms epidemiology, Somatomedins analysis
- Published
- 2001
90. 1,1-Dichloro-2,2-bis(p-chlorophenyl)ethylene and polychlorinated biphenyls and breast cancer: combined analysis of five U.S. studies.
- Author
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Laden F, Collman G, Iwamoto K, Alberg AJ, Berkowitz GS, Freudenheim JL, Hankinson SE, Helzlsouer KJ, Holford TR, Huang HY, Moysich KB, Tessari JD, Wolff MS, Zheng T, and Hunter DJ
- Subjects
- Body Weight, Case-Control Studies, Dichlorodiphenyl Dichloroethylene blood, Environmental Pollutants adverse effects, Environmental Pollutants blood, Female, Humans, Models, Statistical, Multicenter Studies as Topic, Odds Ratio, Polychlorinated Biphenyls blood, Risk Factors, Breast Neoplasms chemically induced, Breast Neoplasms etiology, Dichlorodiphenyl Dichloroethylene adverse effects, Dichlorodiphenyl Dichloroethylene analogs & derivatives, Polychlorinated Biphenyls adverse effects
- Abstract
Background: Environmental exposure to organochlorines has been examined as a potential risk factor for breast cancer. In 1993, five large U.S. studies of women located mainly in the northeastern United States were funded to evaluate the association of levels of 1,1-dichloro-2,2-bis(p-chlorophenyl) ethylene (DDE) and polychlorinated biphenyls (PCBs) in blood plasma or serum with breast cancer risk. We present a combined analysis of these results to increase precision and to maximize statistical power to detect effect modification by other breast cancer risk factors., Methods: We reanalyzed the data from these five studies, consisting of 1400 case patients with breast cancer and 1642 control subjects, by use of a standardized approach to control for confounding and assess effect modification. We calculated pooled odds ratios (ORs) and 95% confidence intervals (CIs) by use of the random-effects model. All statistical tests were two-sided., Results: When we compared women in the fifth quintile of lipid-adjusted values with those in the first quintile, the multivariate pooled OR for breast cancer associated with PCBs was 0.94 (95% CI = 0.73 to 1.21), and that associated with DDE was 0.99 (95% CI = 0.77 to 1.27). Although in the original studies there were suggestions of elevated breast cancer risk associated with PCBs in certain groups of women stratified by parity and lactation, these observations were not evident in the pooled analysis. No statistically significant associations were observed in any other stratified analyses, except for an increased risk with higher levels of PCBs among women in the middle tertile of body mass index (25-29.9 kg/m(2)); however, the risk was statistically nonsignificantly decreased among heavier women., Conclusions: Combined evidence does not support an association of breast cancer risk with plasma/serum concentrations of PCBs or DDE. Exposure to these compounds, as measured in adult women, is unlikely to explain the high rates of breast cancer experienced in the northeastern United States.
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- 2001
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91. The repeatability of serum carotenoid, retinoid, and tocopherol concentrations in specimens of blood collected 15 years apart.
- Author
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Comstock GW, Burke AE, Hoffman SC, Norkus EP, Gross M, and Helzlsouer KJ
- Subjects
- Aged, Arteriosclerosis etiology, Biomarkers analysis, Blood Banks, Case-Control Studies, Female, Humans, Hypertension complications, Male, Middle Aged, Reproducibility of Results, Risk Assessment, Sensitivity and Specificity, Specimen Handling, Carotenoids blood, Retinoids blood, Vitamin E blood
- Abstract
Community-wide programs to collect blood for a research serum bank were carried out in Washington County, Maryland in 1974 and 1989. Of the 8395 persons who participated in both programs, 64 were controls in a nested case-control study of the association of antioxidant micronutrients with subsequent breast cancer, and 30 and 166 were controls in similar studies of lung and prostate cancer. Assay results for five carotenoids, two retinoids, and two tocopherols in samples of blood collected 15 years apart were thus available for comparisons of micronutrient concentrations. The mean Spearman rank order correlation coefficient for all comparisons was 0.44, with two coefficients greater than 0.60 and two less than 0.30. Blood pressure readings at the two blood collections had a mean rank order correlation coefficient of 0.46. Because blood pressure readings in 1974 were shown to be significantly predictive of atherosclerosis 15-18 years later, the present results suggest that ranked concentrations of antioxidant micronutrients from a single sample are sufficiently representative to be used as predictors of subsequent concentrations and are thus suitable for assessment as risk factors for subsequent illnesses.
- Published
- 2001
92. Effects of repeated freeze-thaw cycles on concentrations of cholesterol, micronutrients, and hormones in human plasma and serum.
- Author
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Comstock GW, Burke AE, Norkus EP, Gordon GB, Hoffman SC, and Helzlsouer KJ
- Subjects
- Blood Donors, Cryopreservation, Female, Humans, Male, Blood Specimen Collection, Cholesterol blood, Hormones blood, Micronutrients blood
- Published
- 2001
93. Household exposure to passive cigarette smoking and serum micronutrient concentrations.
- Author
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Alberg AJ, Chen JC, Zhao H, Hoffman SC, Comstock GW, and Helzlsouer KJ
- Subjects
- Adult, Cross-Sectional Studies, Educational Status, Female, Humans, Male, Maryland, Middle Aged, Sex Distribution, Carotenoids blood, Tobacco Smoke Pollution, Vitamin A blood, Vitamin E blood
- Abstract
Background: The associations observed between passive smoking and adverse health outcomes have generated controversy. In part, this could be because the diets of passive smokers, like those of active smokers, differ from those of persons who are not exposed to cigarette smoke, especially with regard to antioxidants., Objective: Our objective was to assess the relation between household exposure to passive smoking and serum concentrations of retinol, tocopherols, and carotenoids., Design: A cross-sectional study was conducted in Washington County, MD, to compare exposure to passive smoking at home, recorded in a private census of county residents in 1975, with micronutrient concentrations assayed in serum collected in 1974. This comparison was possible for 1590 control subjects in nested case-control studies conducted between 1986 and 1998., Results: Among persons who were not current smokers, those who lived with smokers tended to have lower serum total carotenoid, alpha-carotene, ss-carotene, and cryptoxanthin concentrations than did those who lived in households with no smokers. There was little evidence that exposure to passive smoking was associated with reduced serum concentrations of lutein and zeaxanthin, lycopene, retinol, alpha-tocopherol, or gamma-tocopherol., Conclusions: Among nonsmokers, exposure to passive smoking tended to be associated with lower serum concentrations of the carotenoids most strongly associated with active smoking (total carotenoids, alpha-carotene, ss-carotene, and cryptoxanthin). The associations were weaker for passive smoking than for active smoking. The consistency of the associations observed for active and passive smoking indicates that exposure to passive smoking may result in decreased circulating concentrations of selected micronutrients.
- Published
- 2000
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94. Catechol-O-methyltransferase polymorphism is not associated with ovarian cancer risk.
- Author
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Goodman JE, Lavigne JA, Hengstler JG, Tanner B, Helzlsouer KJ, and Yager JD
- Subjects
- Case-Control Studies, Female, Genotype, Humans, Middle Aged, Ovarian Neoplasms genetics, Catechol O-Methyltransferase genetics, Glutathione Transferase genetics, Ovarian Neoplasms enzymology, Polymorphism, Genetic
- Abstract
A valine-108-methionine polymorphism in exon 4 of the catechol-O-methyltransferase (COMT) gene causes a 3- to 4-fold reduction in enzyme activity and has been associated with an increased risk of breast cancer. This increased risk may be attributable to a decreased ability of the protein encoded by the low-activity allele (COMT(L)) to methylate and inactivate catechol estrogens, which have been implicated in estrogen carcinogenesis. Because estrogens have also been implicated in the etiology of ovarian cancer, we analyzed 108 cases and 106 controls from a case-control study conducted in Mainz, Germany, to test the hypothesis that COMT(L) is associated with ovarian cancer risk. No significant association was found between the COMT genotype and ovarian cancer risk (for the intermediate-activity COMT genotype versus the high-activity COMT genotype, OR, 1.29; 95% CI, 0.63-2.64; for the low-activity COMT genotype versus the high-activity COMT genotype, OR, 1.17; 95% CI, 0.52-2.61). We also hypothesized that women who were both low-activity COMT genotype- and glutathione S-transferase (GST) M1- and/or T1 null would be at higher risk for ovarian cancer because the combination of these genotypes could theoretically lead to higher catechol estrogen exposure. However, the association between the COMT polymorphism and ovarian cancer risk was similar across GSTM1 and GSTT1 genotypes (Ptrend > 0.40, for all strata). Because of the small sample size of this study population, odds ratios of a small magnitude could not be completely ruled out; however, the results presented do not support a strong association between the COMT polymorphism and the risk of ovarian cancer.
- Published
- 2000
95. Epidemiology, prevention, and early detection of breast cancer.
- Author
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Alberg AJ, Singh S, May JW, and Helzlsouer KJ
- Subjects
- Breast Neoplasms genetics, Female, Humans, Mammography, Prognosis, Risk Factors, Breast Neoplasms diagnosis, Breast Neoplasms epidemiology, Breast Neoplasms prevention & control
- Abstract
Decreases in the incidence of breast cancer have not been achieved, but there is a downward trend in age-adjusted breast cancer mortality rates in the United States. Recent epidemiologic investigations continue to refine our understanding of the role of established breast cancer risk factors, such as reproductive characteristics and body mass index, and in the process advance understanding of the etiology of breast cancer. Important strides are being made in the chemoprevention of breast cancer, but clarifying the potential contributions of factors such as diet, physical activity, and cigarette smoke to the breast cancer burden is a high priority because these lifestyle behaviors also have important implications for primary prevention. The role of both environmental and endogenous exposures in breast carcinogenesis will be more clearly elucidated by studies that account for genetic polymorphisms, some of which may lead to differential susceptibility to harmful agents.
- Published
- 2000
- Full Text
- View/download PDF
96. A case-control study of nitrate in drinking water and non-Hodgkin's lymphoma in Minnesota.
- Author
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Freedman DM, Cantor KP, Ward MH, and Helzlsouer KJ
- Subjects
- Adult, Age Distribution, Aged, Case-Control Studies, Confidence Intervals, Drinking, Female, Humans, Incidence, Logistic Models, Lymphoma, Non-Hodgkin etiology, Male, Middle Aged, Minnesota epidemiology, Odds Ratio, Population Surveillance, Reference Values, Risk Factors, Sex Distribution, Lymphoma, Non-Hodgkin epidemiology, Nitrates adverse effects, Water Pollution, Chemical adverse effects, Water Supply analysis
- Abstract
Nitrate in drinking water has been implicated as a possible risk factor for non-Hodgkin's lymphoma. The authors examined the association between non-Hodgkin's lymphoma and waterborne nitrate through a population-based case-control study of white men in Minnesota. The authors, by linking residential histories with community water records, estimated average long-term exposure to nitrate in drinking water from 1947 to 1975 for 73 cases diagnosed between 1980 and 1982 and for 147 controls who used community water supplies. No association was found between nitrate levels in community water supplies and non-Hodgkin's lymphoma within the range of study exposures (median of highest exposure category = 2.4 mg nitrate/l [range = 0.1-7.2 mg/l]). The findings provide some safety assurance for those who use water systems that have nitrate levels that are less than 2.4 mg/l.
- Published
- 2000
- Full Text
- View/download PDF
97. Estrogen-progestin replacement and risk of breast cancer.
- Author
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Newschaffer CJ and Helzlsouer KJ
- Subjects
- Estrogens therapeutic use, Female, Humans, Menopause, Ovariectomy, Progestins therapeutic use, Risk, Breast Neoplasms epidemiology, Estrogen Replacement Therapy adverse effects
- Published
- 2000
98. The risk of cervical cancer in relation to serum concentrations of folate, vitamin B12, and homocysteine.
- Author
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Alberg AJ, Selhub J, Shah KV, Viscidi RP, Comstock GW, and Helzlsouer KJ
- Subjects
- Adult, Case-Control Studies, DNA Repair, Female, Humans, Odds Ratio, Risk Assessment, Uterine Cervical Neoplasms etiology, Folic Acid blood, Homocysteine blood, Uterine Cervical Neoplasms epidemiology, Vitamin B 12 blood
- Abstract
Due to its role in the synthesis and repair of DNA, folate may protect against the development of cervical cancer. Prospective data on the possible association between folate and cervical cancer have been lacking. There is also a paucity of prospective evidence concerning the possible associations between cervical cancer and vitamin B12, which shares pathways with folate, and homocysteine, a marker of low B vitamin concentrations. A nested case-control study was conducted to prospectively evaluate the associations between cervical cancer and serum concentrations of folate, vitamin B12, and homocysteine. Among a community-based cohort of women who donated blood in 1974 for a serum bank in Washington County, Maryland, 39 cases of cervical cancer diagnosed between 1975 and mid-1990 were included in the study (13 cases of invasive cervical cancer and 26 cases of carcinoma in situ). Two controls were matched to each case by age, race, and sex. Stored serum from the cases and controls was assayed for folate, B12, and homocysteine concentrations. For folate, adjusted odds ratios were 1.0, 0.62, and 0.60 for the low to high thirds of the serum concentrations, respectively, a trend in the protective direction that was not statistically significant (P for trend = 0.42). Overall, the results for vitamin B12 tended to mimic those for folate, whereas the associations for homocysteine tended to be in the opposite direction. None of the results of this study were statistically significant, but patterns of the associations are in accord with hypothesized mechanistic pathways concerning B vitamins and cervical cancer.
- Published
- 2000
99. The effects of vitamin C and vitamin E on oxidative DNA damage: results from a randomized controlled trial.
- Author
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Huang HY, Helzlsouer KJ, and Appel LJ
- Subjects
- 8-Hydroxy-2'-Deoxyguanosine, Aged, Antioxidants therapeutic use, Ascorbic Acid therapeutic use, Cell Transformation, Neoplastic, Chemoprevention, Deoxyguanosine urine, Double-Blind Method, Female, Humans, Life Style, Male, Middle Aged, Oxidative Stress, Vitamin E therapeutic use, Antioxidants pharmacology, Ascorbic Acid pharmacology, DNA Damage, Deoxyguanosine analogs & derivatives, Vitamin E pharmacology
- Abstract
Oxidative DNA damage may be important in mutagenic, carcinogenic, and aging processes. Although it is plausible that antioxidant vitamins may reduce oxidative DNA damage, evidence from human studies has been sparse and inconsistent. We determined the short-term effects of vitamin C (500 mg/day) and vitamin E (400 IU d-alpha-tocopheryl acetate/day) supplements on oxidative DNA damage in a double-masked, placebo-controlled, 2x2 factorial trial in 184 nonsmoking adults. Mean duration of supplementation was 2 months. Oxidative DNA damage was measured by 24-h urinary excretion of 8-hydroxy-2'-deoxyguanosine (8-OHdG). At baseline, urinary 8-OHdG (mean +/- SE; ng/mg creatinine) was associated with race (15.6 +/- 0.8 in African Americans versus 20.3 +/- 1.2 in Caucasians, P = 0.001), prior antioxidant supplement use (18.6 +/- 0.8 in users versus 13.8 +/- 1.5 in non-users, P = 0.007), and regular exercise (19.2 +/- 1.1 in exercisers versus 16.6 +/- 0.9 in non-exercisers, P = 0.04). Fruit and vegetable intake and serum ascorbic acid were inversely associated with urinary 8-OHdG (P-trend = 0.02 and 0.016, respectively). The benefits of fruit and vegetable intake became evident with the consumption being at least three servings/day. At the end of supplementation, change from baseline in urinary 8-OHdG (mean +/- SE; ng/mg creatinine) was -0.6 +/- 1.4 (P = 0.61), 0.6 +/- 1.1 (P = 0.59), 0.5 +/- 1.0 (P = 0.61), and 1.6 +/- 1.4 (P = 0.27) in the placebo, vitamin C alone, vitamin E alone, and combined vitamins C and E groups, respectively. In overall and subgroup analyses, there was no significant main effect or interaction effect of the supplements on urinary 8-OHdG. In conclusion, supplementation of diet with vitamin C (500 mg/day) and vitamin E (400 IU d-alpha-tocopheryl acetate/day) had no significant main effect or interaction effect on oxidative DNA damage as measured by urinary 8-OHdG in nonsmoking adults. However, several aspects of a healthy lifestyle were associated with lower oxidative DNA damage.
- Published
- 2000
100. Serum dehydroepiandrosterone and dehydroepiandrosterone sulfate and the subsequent risk of developing colon cancer.
- Author
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Alberg AJ, Gordon GB, Hoffman SC, Comstock GW, and Helzlsouer KJ
- Subjects
- Adult, Age Factors, Aged, Case-Control Studies, Colonic Neoplasms blood, Colonic Neoplasms etiology, Disease Susceptibility blood, Humans, Male, Middle Aged, Prospective Studies, Risk Factors, Sex Factors, Colonic Neoplasms epidemiology, Dehydroepiandrosterone blood, Dehydroepiandrosterone Sulfate blood
- Abstract
This purpose of this study was to evaluate whether serum dehydroepiandrosterone (DHEA) and its sulfate conjugate, dehydroepiandrosterone sulfate (DHEAS), are associated with the likelihood of developing colon cancer. A nested case-control study was conducted using the serum bank and cancer registry in Washington County, Maryland. From a population of 20,305 county residents who donated blood in 1974, incident cases of colon cancer that occurred from 1975 to 1991 (n = 117) were matched to one cancer-free control by age, race, and sex. Serum specimens that were stored at -70 degrees C since 1974 were assayed for DHEA and DHEAS. Compared with the controls, the mean serum concentrations of cases were 3% lower for DHEA (P = 0.90) and 13% lower for DHEAS (P = 0.60). When DHEA levels were analyzed according to fourths, no noteworthy associations were observed. Compared with the lowest fourth, the highest fourth of serum DHEAS was nonsignificantly associated with a halving in the risk of colon cancer (odds ratio, 0.50; 95% confidence limits, 0.18, 1.37; Ptrend = 0.22), and further analyses showed the potential protective association was confined largely to males (highest-versus-lowest fourth odds ratio, 0.26; 95% confidence limits, 0.06, 1.16; Ptrend = 0.06). This prospective study does not provide strong evidence that circulating DHEA and DHEAS concentrations are associated with the risk of colon cancer. Among men, DHEAS was associated with a decreased risk of colon cancer, but the association was within the bounds of chance. Further studies are needed to either support or refute the potentially promising lead hinted at by the results for DHEAS.
- Published
- 2000
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