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PubMed2004

Associations between breast cancer susceptibility gene polymorphisms and clinicopathological features.

PURPOSE: Genetic polymorphisms may affect not only cancer development but also cancer progression, and as a result could influence cancer phenotypes. The aim of this study was to examine the relationship between breast cancer susceptibility gene polymorphisms and clinicopathological features. EXPERIMENTAL DESIGN: We genotyped 664 Korean primary breast cancer patients for 17 single-nucleotide polymorphisms (SNPs) in nine genes, using a high-throughput SNP scoring method. RESULTS: CYP1A1 codon 462 Ile/Val or Val/Val variants and the CYP1B1 codon 432 Leu/Val variant were found more in breast cancer patients </=35 years of age at onset than the common homozygote [odds ratio (OR), 1.6 and 1.7, respectively]. In combination analysis of these two SNPs, the OR was 1.9 when one of them was heterozygous or a rare homozygous form, and increased to 2.3 when both were variants (P = 0.006). Cases with Ile/Val at CYP1A1 codon 462 were 2.6-fold and those with Val/Val were 5.1-fold more likely to have first-degree relatives with breast cancer than those with Ile/Ile (P = 0.002). In the haplotype study of BRCA1, the 2430C/2731T/3667G/4427C/4956G homozygote showed less estrogen receptor negativity than the most common diplotype (OR, 0.5; 95% confidence interval, 0.26-0.94). TP53 codon 72 Arg/Pro or Pro/Pro variants were associated with negative axillary lymph node status (OR, 0.7; 95% confidence interval, 0.49-0.94). CONCLUSIONS: These results indicate that polymorphisms of some selected breast cancer susceptibility genes are associated with the clinicopathological phenotypes of breast cancer.

Adult↗
PubMed2004

CYP1A1, cigarette smoking, and colon and rectal cancer.

Cytochrome P-450 (CYP) is involved in the activation and metabolism of polycyclic aromatic hydrocarbons in tobacco products. The authors evaluated the association of two polymorphisms in the CYP1A1 gene--the noncoding Msp I polymorphism in the 3'-untranslated region and the Ile462Val polymorphism in exon 7--with colon and rectal cancer. The authors used data from two incident case-control studies of colon cancer (1,026 cases and 1,185 controls) and rectal cancer (820 cases and 1,036 controls) conducted in California and Utah (1991-2002). CYP1A1 genotype was not associated with colon or rectal cancer. Having GSTM1 present, a CYP1A1 variant allele, and the rapid-acetylator NAT2 imputed phenotype was associated with increased risk of colon cancer (odds ratio = 1.7, 95% confidence interval: 1.2, 2.3). Among men, the greatest colon cancer risk was observed for having any CYP1A1 variant allele and currently smoking (odds ratio = 2.5, 95% confidence interval: 1.3, 4.8; Wald chi(2)test: p < 0.01). Assessment of GSTM1 and CYP1A1 and rectal cancer in men showed a twofold elevation in risk for more than 20 pack-years of smoking, except among those with GSTM1 present who had a variant CYP1A1 allele. These data support the association between smoking and colon and rectal cancer. Smoking may have a greater impact on colorectal cancer risk based on CYP1A1 genotype; this might further be modified by GSTM1 for rectal cancer risk.

3' Untranslated Regions↗
PubMed2003

Allelic variants of cytochromes P450 2C modify the risk for acute myocardial infarction.

SUMMARY: Cytochromes P450 (CYP) 2C8 and 2C9 are polymorphic enzymes responsible for the biosynthesis of vasoactive substances from arachidonic acid including endothelium-derived hyperpolarizing factor. Inter-individual differences in the action of these substances might be important in the pathogenesis of cardiovascular diseases such as acute myocardial infarction (AMI) and hypertension. This study describes the relationship between genetic variants of CYP2C8 and CYP2C9, and morbidity in myocardial infarction in a large Swedish patient material. The study included 1172 AMI patients and 1503 control subjects (matched by age, sex and residential area) who participated in the Stockholm Heart Epidemiology Program (SHEEP). Genotyping was performed by allelic discrimination using a 5'-nuclease assay for the CYP2C8 and CYP2C9 variants. To estimate associations to AMI risks, odds ratios (OR) with 95% confidence intervals (CI) were calculated. The frequencies of CYP2C8*1, 2C8*3, 2C9*1, 2C9*2 and 2C9*3 variants in the control group were 0.91, 0.095, 0.83, 0.11 and 0.065, respectively. The risk of AMI in the female individuals carrying the *2 or *3 variant alleles of CYP2C9 and that of all individuals carrying the *3 variant of CYP2C8 was higher [OR (95% CI): 1.3 (1.0-1.9), P = 0.09; 1.5 (1.0-2.2), P = 0.06 and 1.2 (1.0-1.5), P = 0.07, respectively] compared to the groups with CYP2C8*1 and CYP2C9*1. Possession of rare genetic variants of the CYP2C8 and CYP2C9 genes in females is associated with a modest increase in risk of AMI. This might be related to genetic differences in the formation of endogenous vasoregulating eicosanoids.

Alleles↗
PubMed1997

Genomic variation of human papillomavirus type 16 and risk for high grade cervical intraepithelial neoplasia.

BACKGROUND: Epidemiologic studies have demonstrated strong and consistent associations between the detection of human papillomavirus (HPV) type 16 DNA and the risk of cervical intraepithelial neoplasia (CIN) and cervical cancer. However, HPV16 is also the most common type of HPV in the normal population, and only a minority of women with HPV16 infection develop cervical cancer. Studies of genomic heterogeneity in HPV16 have demonstrated the presence of multiple variant forms in all human populations examined to date. It is conceivable that the natural variants of HPV16 in a given population may not have the same biologic behavior. PURPOSE: This study was designed to determine the association between natural variants of HPV16 and the risk of biopsy-confirmed CIN 2 or 3, the most important precancerous lesions of the uterine cervix. METHODS: Prospective studies were conducted among 1) women attending a university and 2) women presenting to a sexually transmitted disease clinic. Subjects were eligible for inclusion in this investigation if the initial cytologic findings did not reveal CIN 2-3 and HPV16 DNA was detected by means of a polymerase chain reaction (PCR)-based method in one or more cervical or vulvovaginal samples. Eligible subjects were followed every 4 months with cervical Pap smears and colposcopic examinations. Women were referred for biopsy if cytology or colposcopy suggested CIN 2-3. Two groups of HPV16 variants, prototype-like and nonprototype-like, were determined by means of single-strand conformation polymorphism (SSCP) analysis of PCR products from the noncoding region of the viral genome. Representative SSCP patterns from HPV16 variants were further characterized by direct DNA sequencing of the PCR products. Relative risks (RRs) and 95% confidence intervals (CIs) were calculated by Cox regression analysis. RESULTS: Prototype-like variants accounted for 79% of the HPV16 detected in university students and 86% of the virus detected in patients presenting to the sexually transmitted disease clinic. CIN 2-3 was confirmed by biopsy in nine of 57 HPV16-positive women attending the university and in 10 of 66 HPV16-positive women presenting to the sexually transmitted disease clinic. Among university students, those with HPV16 nonprototype-like variants were 6.5 (95% CI = 1.6-27.2) times more likely to develop CIN 2-3 than those with prototype-like variants. A similar association was observed among women presenting to the sexually transmitted disease clinic (RR = 4.5; 95% CI = 0.9-23.8). CONCLUSIONS: This study suggests that the risk of developing CIN 2-3 is not the same with all variants of HPV16 and that nonprototype-like variants confer a greater risk compared with prototype-like variants. The important genomic differences underlying this increased risk of CIN 2-3 remain to be determined.

Adolescent↗
PubMed2004

Polymorphism in the surfactant protein-B gene, gender, and the risk of direct pulmonary injury and ARDS.

STUDY OBJECTIVE: Major risk factors for ARDS have been identified. However, only a minority of patients with such risks develops ARDS. It is likely that, given the same type and degree of insult, there are heritable determinants of susceptibility to ARDS. To investigate the possibility of variable genetic susceptibility to ARDS, we examined the association between ARDS and a polymorphism in intron 4 of the surfactant protein-B (SP-B) gene. DESIGN: Nested case-control study conducted from September 1999 to March 2001. SETTING: Four adult medical and surgical ICUs at a tertiary academic center. PATIENTS: One hundred eighty-nine patients meeting study criteria for a defined risk factor for ARDS were enrolled and prospectively followed. MEASUREMENTS AND RESULTS: Seventy-two patients (38%) developed ARDS. After stratification by gender and adjustment for potential confounders, there was a significantly increased odds for women with the variant SP-B gene to develop ARDS compared to women homozygous for the wild-type allele (odds ratio [OR], 4.5; 95% confidence interval [CI], 1.1 to 18.8; p = 0.03). Women with the variant SP-B polymorphism also had significantly increased odds of having a direct pulmonary injury such as aspiration or pneumonia as a risk factor for ARDS as opposed to an indirect pulmonary risk for ARDS (OR, 4.6; 95% CI, 1.1 to 19.9; p = 0.04). No such association with ARDS or direct pulmonary injury was found for men. CONCLUSION: The variant polymorphism of the SP-B gene is associated with ARDS and with direct pulmonary injury in women, but not in men. Further study is needed to confirm the association between the variant SP-B gene, and gender, ARDS, and direct pulmonary injury.

Adolescent↗
PubMed2006

Combined effects of the p53 and p73 polymorphisms on lung cancer risk.

Lung cancer is a multigenic disease where one variant single nucleotide polymorphism may have only a modest independent effect on the disease phenotype, yet in aggregate, multiple biologically relevant single nucleotide polymorphisms may provide a more accurate representation of risk. Polymorphisms in members of the p53 family, such as p53 and p73, that have a functional relevance would be predicted to contribute to the disease phenotype. In this analysis, we used genotype data from 863 lung cancer cases and 852 healthy controls to test for multigenetic effects of polymorphisms at p53 exon 4, introns 3 and 6, and at p73 exon 2. All individuals in this analysis were self-reported non-Hispanic Caucasians. When the p73 and p53 variant alleles were combined and analyzed as a continuous variable, there was a 13% increase [odds ratios (OR), 1.13; 95% confidence intervals (CI), 1.05-1.21] in lung cancer risk for each additional variant allele. Furthermore, when the number of variant alleles was categorized into three groups (zero, one to three, and four or more variants), there was evidence of a gene-dosage effect with increased risks for individuals with one to three variants (OR, 1.30; 95% CI, 1.05-1.61) and four or more variants (OR, 1.78; 95% CI, 1.23-2.56). When the data were stratified by smoking status, an increased risk for lung cancer was evident only in current (OR, 2.32; 95% CI, 1.25-4.33) and former smokers (OR, 1.73; 95% CI, 1.02-2.94) with four or more variants. Younger individuals with four or more variants were also at a significantly increased risk for lung cancer (OR, 3.15; 95% CI, 1.62-6.12). This study provides support for the multigenetic effects of variant alleles from p53 exon 4, and introns 3 and 6, and p73, and their interplay with smoking, resulting in a significantly increased risk for lung cancer in this Caucasian population.

Aged↗
PubMed1998

Risk of stroke in young women and two prothrombotic mutations: factor V Leiden and prothrombin gene variant (G20210A)

BACKGROUND AND PURPOSE: Factor V Leiden and a prothrombin gene variant, G20210A, are mutations associated with a thrombotic risk. The aim of our study was to assess whether these mutations increase the risk of stroke in women under 45 years of age. METHODS: We conducted a case-control study in western Washington state. Case patients were women aged 18 to 44 years with a first stroke (n = 106). Control subjects were women without stroke recruited from the same region by use of random-digit telephone dialing (n = 391). All were interviewed and provided blood specimens, which were genotyped for these mutations. RESULTS: Factor V Leiden was found in 0.9% of case patients, a single patient with a subarachnoid hemorrhage, and in 4.1% of control subjects. The odds ratio (OR) for any stroke was 0.2 (95% confidence interval [CI], 0.03 to 1.7). The prothrombin variant was found in 1.9% of case patients, 1 with a venous stroke and 1 with an ischemic stroke, and in 1.6% of control subjects. The OR for any stroke was 1.48 (95% CI, 0.14 to 9.17). ORs for stroke types were also not statistically significant. CONCLUSIONS: In this study, neither factor V Leiden nor the prothrombin variant (G20210A) was an important risk factor for stroke in young women. In this setting, screening for these mutations cannot be recommended. Unanswered by this study is whether screening would be useful in select patients, such as those with a strong family history of thrombophilia or those with venous strokes.

Adult↗
PubMed2002

Bioequivalence evaluation of two brands of gliclazide 80 mg tablets (Glyzide & Diamicron)--in healthy human volunteers.

A randomized, two-way, crossover, bioequivalence study in 24 fasting, healthy, male volunteers was conducted to compare two brands of gliclazide 80 mg tablets, Glyzide (Julphar, UAE) as test and Diamicron (Servier Industries, France) as reference product. The study was performed at the International Pharmaceutical Research Centre (IPRC), in joint venture with Speciality Hospital, Amman, Jordan. The drug was administered with 240 ml of 20% glucose solution after a 10 h overnight fasting. After dosing, serial blood samples were collected for a period of 48 h. Plasma harvested from blood was analyzed for gliclazide by validated HPLC method. Various pharmacokinetic parameters including AUC(0-t), AUC(0- proportional, variant), C(max), T(max), T(1/2), and elimination rate constant were determined from plasma concentrations of both formulations. Statistical modules (ANOVA and 90% confidence intervals) were applied to AUC(0-t), AUC(0- proportional, variant), and C(max) for bioequivalence evaluation of the two brands which revealed no significant difference between them, and 90% CI fell within US FDA accepted bioequivalence range of 80-125%. Based on these statistical inferences, Glyzide was judged bioequivalent to Diamicron.

Adolescent↗
PubMed2001

Polymorphic hCHK2/hCds1 codon 84 allele and risk of squamous cell carcinoma of the head and neck--a case-control analysis.

Checkpoint kinase 2 (hCHK2/hCds1) is a tumor suppressor gene involved in cell-cycle control. A hCHK2/hCds1 polymorphism in codon 84 (A-->G at nucleotide 252) was recently identified in Li-Fraumeni syndrome patients. Because cell cycle regulates DNA repair that is associated with cancer risk, we hypothesized that this new polymorphism exists in the general population and is associated with cancer risk. To test this hypothesis, we evaluated the role of this polymorphism in a case-control study of 215 non-Hispanic white patients with newly diagnosed squamous cell carcinoma of the head and neck (SCCHN) and 229 frequency-matched cancer-free controls. We found that the hCHK2/hCds1 codon 84 variant was rare and less frequent in non-Hispanic white cases (0.0186) than in controls (0.0437; P = 0.033). Although no variant homozygotes were detected in these cases and controls, heterozygosity protected against SCCHN, representing a 60% reduction of risk (adjusted odds ratio = 0.40; 95% confidence intervals, 0.17-0.93) compared with wild-type homozygotes. The variant allele was also rare in other ethnic groups (0.0487, 0.0095 and 0.0541 in 115 African Americans, 105 Hispanic Americans and 111 native Chinese, respectively), and only one variant homozygous individual (a Chinese subject) was identified. These results suggest that this hCHK2/hCds1 codon 84 polymorphism is rare and may have a protective role in the aetiology of SCCHN in non-Hispanic whites. Larger studies are warranted to confirm this finding and further mechanistic studies are needed to understand biological relevance of this polymorphism.

Aged↗
PubMed2005

Interindividual variation in nucleotide excision repair genes and risk of endometrial cancer.

Exposure to estrogens is a likely cause of endometrial cancer, but the means by which estrogens exert this effect are not entirely clear. One hypothesis is that certain estrogen metabolites bind to the DNA, forming bulky adducts that damage the DNA and initiate carcinogenesis. A woman's reduced capacity to repair such damage may increase her risk of endometrial cancer. We conducted a population-based case-control study in western Washington State to address the role of variation in nucleotide excision repair genes on the risk of endometrial cancer. Case women (n = 371), ages 50 to 69 years, were diagnosed with invasive endometrial cancer between 1994 and 1999. Control women (n = 420) were selected using random-digit dialing (ages 50-65 years) and by random selection from Health Care Financing Administration data files (ages 66-69 years). Genotyping assays were done for ERCC1, ERCC2 (XPD), ERCC4 (XPF), ERCC5 (XPG), XPA, and XPC. No appreciable differences between cases and controls were observed in the genotype distributions of ERCC1 (c8092a and c19007t), ERCC2 (D312N, K751Q, and c22541a), ERCC4 (R415Q and t30028c), or ERCC5 (D1104H). Carriage of at least one variant allele for XPA G23A was associated with decreased risk of endometrial cancer [odds ratio (OR), 0.70; 95% confidence interval (95% CI), 0.53-0.93]. Carriage of at least one XPC A499V variant allele was associated with a modest decrease in risk (OR, 0.79; 95% CI, 0.59-1.05). Women with variant alleles at both XPC A499V and K939Q had 58% of the risk of women with no XPC variant alleles (OR, 0.58; 95% CI, 0.35-0.96). Our data suggest that interindividual variation in XPA and XPC influences a woman's risk of endometrial cancer.

Aged↗
PubMed1997

Lipoprotein lipase gene variants and risk of coronary disease: a quantitative analysis of population-based studies.

The purpose of this study is to quantify the magnitude of the association between common variants in the lipoprotein lipase gene and coronary disease, based on published population-based studies. Fourteen studies, representing 15,708 subjects, report allelic distribution for lipoprotein lipase gene variants among coronary disease patients and control subjects. Patient outcomes included clinical coronary disease events and documented coronary disease based on angiography. Allele frequencies are estimated for disease and non-disease groups within each study. A 2 x 2 contingency table is used to compute individual study odds ratios and 95% confidence intervals, relating the presence of the rare allele to disease status. Mantel-Haenszel-stratified analysis of each allelic variant results in a summary odds ratio and 95% confidence interval for the association between each rare allele in the lipoprotein lipase gene and coronary disease. The lipoprotein lipase D9N allele has a summary odds ratio of 1.59 (95% confidence interval 1.03-2.55), indicating a 59% increase in risk of coronary disease for carriers with this allelic variant. The lipoprotein lipase N291S allele showed no association with coronary disease (summary odds ratio 0.93, 95% confidence interval 0.73-1.19). The summary odds ratio for lipoprotein lipase S447Ter allele is 0.81 (95% confidence interval 0.65-1.0), indicating a marginal negative association between this variant and coronary disease. The common lipoprotein lipase Pvu II polymorphism shows no relation to coronary disease (summary odds ratio 0.90, 95% confidence interval 0.80-1.01). The rare allele of the lipoprotein lipase HindIII polymorphism is negatively associated with coronary disease (summary odds ratio 0.84, 95% confidence interval 0.73-0.96). The lipoprotein lipase D9N allele is associated with high levels of triglyceride and low levels of high-density lipoprotein. Similar atherogenic lipid levels are observed in subjects with structural mutations lipoprotein lipase C188E and P207L. Carriers of the S447Ter allele have low levels of triglyceride. The lipoprotein, lipase gene variants which decrease lipoprotein lipase catalytic activity are associated with familial combined hyperlipidemia, but not the elevation of apolipoprotein B seen in this disorder. In conclusion, allelic variants in the lipoprotein lipase gene are associated with altered lipid levels and differential coronary disease risk.

Alleles↗
PubMed2006

An insulin-like growth factor-I promoter polymorphism is associated with increased mortality in subjects with myocardial infarction in an elderly Caucasian population.

We investigated whether an insulin-like growth factor I (IGF-I) promoter polymorphism is associated with excess mortality in elderly subjects with myocardial infarction (MI). This association was assessed in 7,983 subjects of the Rotterdam Study during 14 years of follow-up. Among 345 subjects who developed a MI, the risk of mortality was 1.49 times higher in the variant carriers of the IGF-I promoter polymorphism than in the nonvariant carriers (95% confidence interval 1.10 to 2.10, p = 0.02). The risk of death increased with the number of variant alleles. Our study suggests that genetically determined low IGF-I activity is an important determinant of mortality in subjects with MI.

Aged↗
PubMed2002

Association of human papillomavirus type 58 variant with the risk of cervical cancer.

Human papillomavirus (HPV) type 58 has been found to be prevalent among Chinese patients with cervical cancer. This study examined the oncogenic risk of HPV58 variants in Hong Kong, a southern part of China. Altogether, 1924 women were studied: 42.8% with a normal cervix, 16.2% with cervical intraepithelial neoplasia (CIN) I, 12.7% with CIN II, 20.8% with CIN III, and 7.6% with invasive cervical cancer (ICC). The overall prevalence of HPV58 was 11.4% (220) and increased statistically significantly with the severity of neoplasia (P(trend)<.001, chi(2) test for trend). Among HPV58-positive women, the occurrence of E7 632C-->T (T20I) and E7 760G-->A (G63S) variants (T20I/G63S) showed a positive trend of association with the severity of neoplasia (P(trend)<.001, chi(2) test for trend). HPV58 variants carrying these two substitutions showed an odds ratio (OR) for ICC of 26.79 (95% confidence interval = 10.14 to 74.72), and this OR was 6.9-fold higher than the ORs of variants without these substitutions. Patients with CIN III or ICC who were also infected with T20I/G63S variants had a statistically significant younger age at diagnosis than those infected with other variants (median age = 37 years versus 48 years; P =.038, two-sided Mann-Whitney U test). Thus, HPV58 variants carrying E7 T20I/G63S substitutions may be associated with an increased risk for cervical cancer.

Adult↗
PubMed2005

Multi-detector row CT in evaluation of 94 living renal donors by readers with varied experience.

PURPOSE: To retrospectively assess the accuracy of four-section multi-detector row computed tomography (CT) in the evaluation of renal transplant donors when scans are read by one of multiple readers with varied levels of expertise, by using surgery as the reference standard. MATERIALS AND METHODS: This retrospective study was approved by the institutional review board and complied with the Health Insurance Portability and Accountability Act. Informed consent was waived. Between October 1999 and March 2003, 94 renal donors (42 men, 52 women; mean age, 44 years) underwent four-section multi-detector row CT. Unenhanced scanning of the abdomen was performed with 5-mm section thickness and table speed of 15 mm per rotation. Next, 135-150 mL of nonionic iodinated (300 mg/mL) contrast material was injected intravenously at a rate of 4-5 mL/sec. Contrast material-enhanced CT was initiated 20-25 seconds, 65-70 seconds, and 10 minutes after start of injection. Arterial phase scanning was performed with 1.25-mm section thickness and 7.5-mm table speed. Venous and excretory phase scanning was performed with 2.5-mm section thickness and 15-mm table speed. Each scan was evaluated independently by one of 11 readers for renal vascular and ureteral anatomic variants. Findings at CT were compared with those at surgery. Sensitivity and specificity (with 95% confidence intervals) and accuracy of CT were calculated on the basis of presence or absence of variant anatomy at surgery. RESULTS: CT depicted 107 of 114 renal arteries confirmed at surgery; seven accessory arteries were missed in six donor kidneys. CT depicted 95 of 98 renal veins confirmed at surgery. Sensitivity and specificity of CT were 66% and 100%, 75% and 100%, and 50% and 100%, and overall accuracy was 94%, 97%, and 99%, for identification of variant anatomy of renal arteries, veins, and ureters, respectively. CONCLUSION: Multi-detector row CT as the sole imaging technique in the preoperative evaluation of living renal donors is accurate even when images are read by multiple readers with varied levels of expertise.

Adult↗
PubMed2003

Atrial fibrillation and hypercoagulability: dependent on clinical factors or/and on genetic alterations?

UNLABELLED: It is well known that atrial fibrillation is associated with high incidence of thromboembolic events, propably due to a prothrombotic or hypercoagulable state. However, it is unclear whether or not there is any difference of this prothrombotic state in the clinical subgroups of atrial fibrillation patients, that is, in those with paroxysmal, persistent or permanent atrial fibrillation. From the other side the role of the arrhythmia duration on the changes of coagulative variables in atrial fibrillation patients is not clearly enough. The contribution of genetic and functional alterations in factors of the coagulation and fibrinolytic pathways (that is hemostatic risk factors) to the development of hypercoagulation state in atrial fibrillation requires clarification. We investigated therefore (1) if there are differences in the prothrombotic state between patients with different clinical status of the arrhythmia, (2) if the arrhythmia duration per se could be an independent determinant of the prothrombotic state in all atrial fibrillation patients and (3) if coexistent genetic alterations in haemostatic risk factors in patients with atrial fibrillation could contribute to the development of prothrombotic abnormalities. METHODS: Over a period of 23 months, we studied 55 patients with chronic non-valvular atrial fibrillation. We recruited 18 consecutive patients (13 men, mean age 59 +/- 10 years) with paroxysmal atrial fibrillation 17 patients (11 men, mean age 61 +/- 7 years) with persistent atrial fibrillation who underwent elective successful DC and remained in sinus rhythm at the 3 month visit and 20 patients (14 men mean age 64 +/- 9) with permanent atrial fibrillation. Blood results were compared to 17 age-sex- and race-matched controls. The prothrombotic state was quantified by measurement of plasma levels of fibrinogen, soluble P -selectin (an index of platelet activation) and von Willebrand factor (a marker of endothelial dysfunction). We assessed the frequencies of factor V Leiden and prothrombin variant G20210A to determine whether particular inherited haemostatic risk factors may have contribution to the development of prothrombotic state in atrial fibrillation patients. RESULTS: Permanent atrial fibrillation was associated with significant raised levels of von Willebrand factor, fibrinogen levels and soluble P -selectin compared to matched controls (all p < 0.001) and matched patients with paroxysmal and permanent AF (all p ranged between <0.003 and <0.002). Patients with persistent atrial fibrillation had significantly elevated von Willebrand factor levels (p = 0.0064) and fibrinogen levels (p = 0.002), but not Soluble P -selectin (p = 0.509). when compared to controls. Patients with paroxysmal atrial fibrillation had significantly elevated levels of P -selectin (p = 0.005) and fibrinogen (p = 0.003), but not von Willebrand factor (p =.0.61) compared to controls. Stepwise multiple regression analyses demonstrated that the arrhythmia duration (approximately 3 years) was an independent predictor of abnormal von Willebrand factor, fibrinogen and soluble P -selectin levels. Restoration of sinus rhythm in paroxysmal atrial fibrillation subgroup and successful electrical cardioversion of patients with permanent fibrillation atrial fibrillation did not significantly alter levels of the affected factors. The frequency of factor V Leiden was 8.9 in all studied patients with atrial fibrillation, versus 2.4% in the control group (odds ratio [OR] 4.6 [95% confidence (CI) 1.4-17.5], p = 0.02). The frequency of the prothrombin variant G20210A was 6.4.% compared with control group 1.6% (OR 4.9 [95% confidence interval (CI) 1.2-2.9], p = 0.04). There was a trend towards an increased frequency of factor V Leiden and/or prothrombin variant G20210A in patients age <55 years and in patients living at a particular area of Thrace mountains. CONCLUSIONS: Our results showed that there were significant differences in the prothrombotic state when patients with paroxysmal, and persistent atrial fibrillation were compared to matched that there were significant differences in the prothrombotic state when patients with paroxysmal, and persistent atrial fibrillation were compared to matched patients with permanent atrial fibrillation and controls in sinus rhythm. The duration of the arrhythmia (about 3 years) was an independent predictor of abnormal measured factors. We found for the first time that some genetic alterations in haemostatic risk factors could be coexist in atrial fibrillation patients and may be a contributor to the development of hypercoagulability in atrial fibrillation patients.

Aged↗
PubMed2006

Association between well-characterized lipoprotein-related genetic variants and carotid intimal medial thickness and stenosis: The Framingham Heart Study.

OBJECTIVE: To determine the association of well-characterized lipoprotein-related genetic variants with carotid intimal medial thickness (IMT) and stenosis. METHODS: 3380 men and women from the Framingham Offspring Study underwent carotid ultrasound to determine carotid IMT and stenosis>/=25%. We genotyped 12 variants in 10 lipoprotein-related genes known to be associated with significant differences in lipoprotein levels. RESULTS: For most of the variants, there was no association with carotid IMT. In multivariable, sex-specific analyses, the rare allele of the cholesterol ester transfer protein (CETP) TaqIB variant was associated with lower ICA IMT in men. Hypertension was associated with higher ICA IMT only in male carriers of the rare allele of the APOCIII Sst-1 variant (p for the interaction=0.041). In analyses of carotid stenosis in male, carriers of the lipoprotein lipase (LPL) N291S rare variant showed a higher risk of carotid stenosis (OR=2.59, 95% confidence interval: 1.11-6.02, p=0.028) compared to NN genotype. CONCLUSIONS: While there is no evidence for a significant association of several common lipoprotein-related genetic variants with carotid IMT, our results are consistent with the previously reported role of CETP and LPL genetic variants in cardiovascular risk and the possible modulation of the association between hypertension and carotid IMT by APOCIII Sst-1 variant.

Adolescent↗
PubMed2004

An investigation into the association among preterm birth, cytokine gene polymorphisms and periodontal disease.

OBJECTIVE: To investigate a putative relationship between preterm delivery and the carriage of polymorphic genes that code for the cytokines interleukin-1beta (IL-1beta) at codon +3953 and tumour necrosis factor-alpha (TNF-alpha) at codon -308 in a group of postpartum women and to elucidate if the concurrent presence of periodontal disease increased the risk of preterm delivery in this group. DESIGN: Case-control study SETTING: Postnatal wards at Guy's and St Thomas' Hospital Trust. POPULATION: Postpartum women from southeast London, UK. METHODS: Case subjects were defined as those who experienced a birth at less than 37 weeks of gestation. Control subjects gave birth at term. Demographic data were collected and a periodontal examination was performed. Blood samples were collected and analysed by restriction fragment length polymerase techniques for the presence of each of the allelic variants. MAIN OUTCOME MEASURES: The level of periodontal disease and the carriage of allelic variants of IL-1beta+3953 and TNF-alpha-308 genes. RESULTS: Forty-eight case subjects and 82 control subjects were assessed. There was no statistically significant difference in the carriage of the IL-1beta+3953 allelic variant between cases and controls (29%versus 18%, P= 0.112). However, 23 (48%) of the case subjects and 24 (29%) of controls were heterozygous or homozygous for the variant TNF-alpha-308 gene (odds ratio [OR] 2.2, 95% confidence interval [CI] 1.0-5.0, P= 0.026). There was no association between the carriage of either the polymorphic IL-1beta+3953 or TNF-alpha-308 variant and the severity of periodontal disease. The combination of periodontal disease and the allelic variant did not increase the risk of preterm delivery. CONCLUSIONS: In this study, a higher proportion of women who delivered preterm carried the polymorphic TNF-alpha-308 gene. There did not appear to be any interaction between either of the genotypes and periodontal disease with preterm delivery as has been reported for bacterial vaginosis and the TNF-alpha-308 polymorphic gene.

Adult↗
PubMed2005

Preoperative MRI of potential living-donor-related liver transplantation using a single dose of gadobenate dimeglumine.

OBJECTIVE: This article evaluates the feasibility of single-dose gadobenate dimeglumine-enhanced MRI as both an angiographic and biliary contrast medium for making a preoperative evaluation of the donor candidates for a living-donor-related liver transplantation. SUBJECTS AND METHODS: Eleven right hepatic lobe donors underwent MRI examinations using T1- and T2-weighted imaging and T2-weighted MR cholangiography (MRC). The MR angiography (MRA) and contrast-enhanced (CE) T1-weighted MRC images then were obtained after injecting a single dose of gadobenate dimeglumine. One radiologist and one surgeon prospectively reviewed all the MRI examinations for hepatic vascular and biliary abnormalities and compared them with the surgical findings and intraoperative cholangiograms. In addition, two blinded reviewers evaluated the two sets of MRC (T2-weighted MRC set and T2-weighted MRC plus CE-T1-weighted MRC set) retrospectively and recorded the anatomic types of the hilar biliary branching pattern along with their confidence in the interpretation. RESULTS: Prospective analysis detected the following vascular variants: hepatic arterial variation in two patients, portal venous variation in one, and a significantly large accessory hepatic vein (> 5 mm) in one. Biliary variants also were identified in two patients. All the MRI findings on the vascular and biliary anatomy were corroborated intraoperatively. Retrospective analysis showed that the mean diagnostic confidence in the combined set was significantly higher than that of the T2-weighted MRC alone by both reviewers (p < 0.05). CONCLUSION: Obtaining both MRA and CE-T1-weighted MRC is feasible using a single dose of gadobenate dimeglumine. Therefore, gadobenate dimeglumine-enhanced MRI might play a role as a preoperative imaging technique for the vascular and biliary evaluation of potential living donors.

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