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1.
J Phys Chem A ; 114(43): 11825-32, 2010 Nov 04.
Article in English | MEDLINE | ID: mdl-20923209

ABSTRACT

This work presents thermochemical data for possible gas phase intermediate species in an industrial rutile chlorinator. An algorithm developed for previous work is employed to ensure that all possible species are considered, reducing the number of important species neglected. Thermochemical data and enthalpies of formation are calculated for 22 new species using density functional theory, post Hartree-Fock coupled cluster calculations, and statistical mechanics. Equilibrium calculations are performed to identify whether any Ti/C intermediates are likely to be important to the high temperature industrial process. These new species are not present at high concentration in the exit stream. It is therefore likely that the two chemical processes do not interact. Rather, the Cl2 rapidly reacts with the solid TiO2 to form TiCl4 and O2. The latter then reacts with the solid C to form CO and CO2 and provide the heat. Data for all the new species is provided as Supporting Information. Finally, a new methodology for data collaboration is investigated in which the data is made openly accessible using the resource description framework. Example scripts are provided to demonstrate how to query and retrieve the data automatically.


Subject(s)
Chlorides/chemistry , Quantum Theory , Thermodynamics , Algorithms , Gases/chemistry , Oxygen/chemistry , Titanium/chemistry
3.
Nutr Cancer ; 56(1): 31-9, 2006.
Article in English | MEDLINE | ID: mdl-17176215

ABSTRACT

Prospective phytoestrogen exposure was assessed using both biomarkers and estimates of intake in 89 British men recruited into the Norfolk arm of the European Prospective Investigation into Cancer and Nutrition study, men who subsequently developed prostate cancer. Results were compared with those from 178 healthy men matched by age and date of recruitment. Levels of seven phytoestrogens (daidzein, genistein, glycitein, O-desmethylangolensin, equol, enterodiol, and enterolactone) were measured in spot urine and serum samples. Five single-nucleotide polymorphisms in COMT, CYP19, ESR1, and SHBG genes were genotyped. Urinary levels of all phytoestrogens correlated strongly with serum levels. Correlation coefficients ranged from 0.63 (glycitein) to 0.88 (daidzein) (P < 0.001). Urinary and serum levels correlated significantly with isoflavone intake assessed from food diaries (R = 0.15-0.20; P < 0.05) but not with that from a food-frequency questionnaire. Odds ratios for phytoestrogen exposure, as assessed using the four methods, were not significantly associated with prostate cancer risk (P = 0.15-0.94). Men with the CC genotype for the ESRI PvuII polymorphism had significantly higher risk for prostate cancer compared with men with the TT genotype [adjusted odds ratio = 4.65 (1.60-13.49); P = 0.005]. Our results utilizing a combined prospective exposure provide no evidence that phytoestrogens alter prostate cancer risk in British men, whereas the C allele for the PvuII polymorphism may be associated with increased risk.


Subject(s)
Diet , Phytoestrogens , Polymorphism, Single Nucleotide/genetics , Prostatic Neoplasms/genetics , Prostatic Neoplasms/metabolism , Aged , Biomarkers/blood , Biomarkers/urine , Genotype , Humans , Male , Middle Aged , Odds Ratio , Phytoestrogens/administration & dosage , Phytoestrogens/blood , Phytoestrogens/urine , Prospective Studies , Risk Factors , United States/epidemiology
4.
J Nutr ; 135(11): 2680-6, 2005 Nov.
Article in English | MEDLINE | ID: mdl-16251630

ABSTRACT

Phytoestrogens have been hypothesized to protect against prostate cancer via modulation of circulating androgen concentrations. We conducted a cross-sectional study of 267 men in the Norfolk arm of the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort with 2 aims: first, to investigate the association between phytoestrogen exposure (measured from diet, urine, and serum) and plasma concentrations of sex hormone-binding globulin (SHBG), androstanediol glucuronide, testosterone and Free Androgen Index (FAI); and second, whether the association may be modified by polymorphisms in CYP19 and SHBG genes. Dietary daidzein and genistein intakes were obtained from food diaries and computed using an in-house food composition database. Urinary and serum concentrations of 3 isoflavones (daidzein, genistein, glycitein), 2 daidzein metabolites O-desmethylangolensin (O-DMA) and 2 lignan metabolites (enterodiol and enterolactone) were measured using mass spectrometry. There was no association between dietary, urinary, and serum phytoestrogens and plasma SHBG concentrations. Enterolactone was positively associated with plasma androstanediol glucuronide concentrations (urinary enterolactone: r = 0.127, P = 0.043; serum enterolactone: r = 0.172, P = 0.006) and FAI (urinary enterolactone: r = 0.115, P = 0.067; serum enterolactone: r = 0.158, P = 0.011). Both urinary and serum equol were associated with plasma testosterone (urinary equol: r = 0.332, P = 0.013; serum equol: r = 0.318, P = 0.018) and FAI (urinary equol: r = 0.297, P = 0.027; serum equol: r = 0.380, P = 0.004) among men with the TT genotype but not the CC or CT genotypes (r = -0.029 to -0.134, P = 0.091-0.717) for the CYP19 3'untranslated region (UTR) T-C polymorphism. Urinary and serum enterolactone showed similar genotype-dependent associations with testosterone but not with FAI. In this first study on phytoestrogen-gene associations in men, we conclude that enterolactone and equol are positively associated with plasma androgen concentrations, and interactions with CYP19 gene may be involved.


Subject(s)
Androgens/blood , Aromatase/genetics , Phytoestrogens/blood , Phytoestrogens/urine , Polymorphism, Genetic/genetics , 4-Butyrolactone/analogs & derivatives , 4-Butyrolactone/blood , 4-Butyrolactone/urine , Aged , Androstane-3,17-diol/analogs & derivatives , Androstane-3,17-diol/blood , Diet , Equol , Genistein/administration & dosage , Genotype , Humans , Isoflavones/administration & dosage , Isoflavones/blood , Isoflavones/urine , Lignans/blood , Lignans/urine , Male , Middle Aged , Phytoestrogens/administration & dosage , Sex Hormone-Binding Globulin/analysis , Testosterone/blood
6.
Cancer Epidemiol Biomarkers Prev ; 14(7): 1828-31, 2005 Jul.
Article in English | MEDLINE | ID: mdl-16030124

ABSTRACT

A substantial proportion of the familial risk of breast cancer may be due to genetic variants, each contributing a small effect. The protein encoded by ERCC2 is a key enzyme involved in nucleotide excision repair, in which gene defects could lead to cancer prone syndromes such as Xeroderma pigmentosum D. We have examined the association between single nucleotide polymorphisms in the ERCC2 gene and the incidence of invasive breast cancer in three case-control series, with a maximum of 3,634 patients and of 3,340 controls. None of the three single nucleotide polymorphisms were significantly associated with the incidence of breast cancer.


Subject(s)
Breast Neoplasms/genetics , DNA Helicases/genetics , DNA-Binding Proteins/genetics , Polymorphism, Single Nucleotide/genetics , Population Surveillance/methods , Transcription Factors/genetics , Case-Control Studies , Female , Humans , Middle Aged , Xeroderma Pigmentosum Group D Protein
7.
Org Biomol Chem ; 3(10): 1832-4, 2005 May 21.
Article in English | MEDLINE | ID: mdl-15889163

ABSTRACT

Molecules, as defined by connectivity specified via the International Chemical Identifier (InChI), are precisely indexed by major web search engines so that Internet tools can be transparently used for unique structure searches.

8.
Breast Cancer Res ; 7(2): R204-9, 2005.
Article in English | MEDLINE | ID: mdl-15743501

ABSTRACT

INTRODUCTION: About two-thirds of the excess familial risk associated with breast cancer is still unaccounted for and may be explained by multiple weakly predisposing alleles. A gene thought to be involved in low-level predisposition to the disease is ERBB2 (HER2). This gene is involved in cell division, differentiation, and apoptosis and is frequently amplified in breast tumours. Its amplification correlates with poor prognosis. Moreover, the coding polymorphism I655V has previously been associated with an increased risk of breast cancer. METHODS: We aimed to determine if common polymorphisms (frequency >or= 5%) in ERBB2 were associated with breast cancer risk in a white British population. Five single-nucleotide polymorphisms (SNPs) were selected for study: SNP 1 near the promoter, SNP 2 in intron 1, SNP 3 in intron 4, SNP 4 in exon 17 (I655V), and SNP 5 in exon 27 (A1170P). We tested their association with breast cancer in a large case-control study (n = 2192 cases and 2257 controls). RESULTS: There were no differences in genotype frequencies between cases and controls for any of the SNPs examined. To investigate the possibility that a common polymorphism not included in our study might be involved in breast cancer predisposition, we also constructed multilocus haplotypes. Our set of SNPs generated all existing (n = 6) common haplotypes and no differences were seen in haplotype frequencies between cases and controls (P = 0.44). CONCLUSIONS: In our population, common ERBB2 polymorphisms are not involved in predisposition to breast cancer.


Subject(s)
Genetic Predisposition to Disease , Receptor, ErbB-2/genetics , White People/genetics , Adult , Aged , Aged, 80 and over , Case-Control Studies , England , Exons , Female , Genotype , Haplotypes , Humans , Introns , Middle Aged , Polymorphism, Single Nucleotide , Receptor, ErbB-2/physiology , Risk Factors
9.
Cancer Epidemiol Biomarkers Prev ; 14(1): 213-20, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15668497

ABSTRACT

Cross-sectional studies investigating the relationship between phytoestrogens in diet, urine, or blood with plasma estradiol and sex hormone binding globulin (SHBG) have been inconclusive. We investigated the relationship among phytoestrogen exposure, polymorphisms in the ESR1, COMT, CYP19, and SHBG genes, and plasma estradiol and SHBG levels in 125 free-living postmenopausal women taking part in a cohort study (European Prospective Investigation of Cancer and Nutrition-Norfolk) using three different markers: dietary, urinary, and serum phytoestrogens. Phytoestrogen levels (daidzein, genistein, glycitein, O-desmethylangolensin, equol, enterodiol, and enterolactone) in spot urine and serum were analyzed by gas chromatography/mass spectrometry and liquid chromatography/tandem mass spectrometry, respectively. Plasma estradiol and SHBG were measured by immunoassays. Adjusting for age and body mass index, urinary daidzein, genistein, glycitein, and serum daidzein and glycitein were negatively correlated with plasma estradiol (R = -0.199 to -0.277, P <0.03), with particularly strong associations found in the 18 women with CC genotype for ESR1 PvuII polymorphism (R = -0.597 to -0.834, P < 0.03). The negative correlations observed between isoflavones and estradiol in women as a whole became no longer significant when we excluded women with ESR1 PvuII CC genotype, indicating that the correlations observed were due mainly to this group of women. There was no relationship between dietary isoflavones and plasma estradiol and no association was found between any of the dietary, urinary, and serum phytoestrogen and plasma SHBG or between these factors and polymorphisms in CYP19, SHBG, and COMT. We conclude that higher isoflavone exposure is associated with lower plasma estradiol in postmenopausal women and that this preliminary study is suggestive of the involvement of diet-gene interactions.


Subject(s)
Breast Neoplasms/genetics , Breast Neoplasms/metabolism , Diet , Estradiol/blood , Phytoestrogens/metabolism , Aged , Analysis of Variance , Biomarkers, Tumor/blood , Chromatography, Gas , Cross-Sectional Studies , Europe , Female , Genotype , Humans , Mass Spectrometry , Middle Aged , Phytoestrogens/administration & dosage , Polymorphism, Genetic , Postmenopause , Prospective Studies , Sex Hormone-Binding Globulin/metabolism , Statistics, Nonparametric
10.
Cancer Epidemiol Biomarkers Prev ; 13(5): 698-708, 2004 May.
Article in English | MEDLINE | ID: mdl-15159299

ABSTRACT

Subjects of this study consisted of 333 women (aged 45-75 years) drawn from a large United Kingdom prospective study of diet and cancer, the European Prospective Investigation of Cancer and Nutrition-Norfolk study. Using newly developed gas chromatography/mass spectrometry and liquid chromatography/mass spectrometry methods incorporating triply (13)C-labeled standards, seven phytoestrogens (daidzein, genistein, glycitein, O-desmethylangolensin, equol, enterodiol, and enterolactone) were measured in 114 spot urines and 97 available serum samples from women who later developed breast cancer. Results were compared with those from 219 urines and 187 serum samples from healthy controls matched by age and date of recruitment. Dietary levels were low, but even so, mean serum levels of phytoestrogens were up to 600 times greater than postmenopausal estradiol levels. Phytoestrogen concentrations in spot urine (adjusted for urinary creatinine) correlated strongly with that in serum, with Pearson correlation coefficients > 0.8. There were significant relationships (P < 0.02) between both urinary and serum concentrations of isoflavones across increasing tertiles of dietary intakes. Urinary enterodiol and enterolactone and serum enterolactone were significantly correlated with dietary fiber intake (r = 0.13-0.29). Exposure to all isoflavones was associated with increased breast cancer risk, significantly so for equol and daidzein. For a doubling of levels, odds ratios increased by 20-45% [log(2) odds ratio = 1.34 (1.06-1.70; P = 0.013) for urine equol, 1.46 (1.05-2.02; P = 0.024) for serum equol, and 1.22 (1.01-1.48; P = 0.044) for serum daidzein]. These estimates of risk are similar to those established for estrogens and androgens in postmenopausal breast cancer but need confirmation in larger studies.


Subject(s)
Biomarkers, Tumor/analysis , Breast Neoplasms/diagnosis , Breast Neoplasms/epidemiology , Dietary Supplements , Isoflavones/metabolism , Plant Preparations/metabolism , Adult , Aged , Analysis of Variance , Case-Control Studies , Diet , Humans , Incidence , Isoflavones/blood , Isoflavones/urine , Middle Aged , Odds Ratio , Phytoestrogens , Plant Preparations/blood , Plant Preparations/urine , Probability , Prognosis , Prospective Studies , Reference Values , Registries , Risk Assessment , Sensitivity and Specificity , United Kingdom/epidemiology
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