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M Trevisan

Publications and source records attributed to M Trevisan.

At least 37 records · Page 2Linked to original sources

Drinking pattern and mortality: the Italian Risk Factor and Life Expectancy pooling project.

PURPOSE: To analyze the relationship between an aspect of drinking pattern (i.e., drinking with or without meals) and risk of all-cause and specific-cause mortality. METHODS: The Risk Factors and Life Expectancy Study, is a pooling of a series of epidemiological studies conducted in Italy. Eight-thousand six-hundred and forty-seven men and 6521 women, age 30-59 at baseline, and free of cardiovascular disease, were followed for mortality from all causes, cardiovascular and noncardiovascular, during an average follow-up of 7 years. RESULTS: Drinkers of wine outside meals exhibited higher death rates from all causes, noncardiovascular diseases, and cancer, as compared to drinkers of wine with meals. This association was independent from the cardiovascular disease (CVD) risk factors measured at baseline and the amount of alcohol consumed and seemed to be stronger in women as compared to men. CONCLUSIONS: The present results indicate that drinking patterns may have important health implications, and attention should be given to this aspect of alcohol use and its relationship to health outcomes. The relationship between alcohol consumption and disease has been the focus of intensive scientific investigation (1-9). Most studies to date, however, have limitations. A major drawback is that limited information has been collected regarding the complex issue of alcohol consumption. In many studies, ascertainment of alcohol consumption frequently focused only on quantity of alcohol consumed without considering the many different components of alcohol consumption, particularly drinking pattern (10-12). It has been hypothesized, and preliminary data support the notion, that drinking pattern could have important influences on determining the health effects of alcohol (13,14). The present study examines the relationship between one aspect of drinking pattern (drinking wine outside meals) and mortality in a large cohort of men and women.

Adult↗

Relationship of the Trp64Arg polymorphism of the beta3-adrenoceptor gene to central adiposity and high blood pressure: interaction with age. Cross-sectional and longitudinal findings of the Olivetti Prospective Heart Study.

METHODS: The association of the Trp64Arg polymorphism of the beta3-adrenoceptor (beta3-AR) gene with high blood pressure, central adiposity and other features of the metabolic syndrome was investigated in a large unselected sample of a white male working population in Southern Italy (n = 979). RESULTS: In the whole population, subjects heterozygous for the Trp64Arg mutation (11.2%) were not different from the homozygous Trp64Trp for any of the variables investigated. However, upon stratification for age, among men in the upper tertile of age (> 53 years), the Trp64Arg genotype was associated with higher waist: hip ratio (0.992 +/- 0.021 versus 0.982 +/- 0.037, P< 0.05), serum uric acid (6.34 +/- 1.50 versus 5.75 +/- 1.30 micromol/l, P < 0.05) and systolic blood pressure (144.3 +/- 19.4 versus 136.9 +/- 18.9 mmHg, P< 0.05) compared with the wild-type homozygotes. Accordingly, in the same age group, the carriers of Trp64Arg genotype were more often in the upper tertile of abdominal adiposity (69.7 versus 43.7%, P< 0.02) and serum uric acid (56.3 versus 34.8%, P < 0.02) and were more often hypertensive (68.6 versus 57.6%, P< 0.058) than the Trp64Trp homozygotes. No such differences were observed in younger age groups. No association was found with fasting serum insulin and the homeostasis model assessment (HOMA) index of insulin resistance. Furthermore, in a subgroup of 457 men for whom retrospective 20-year follow-up data were available, the variant genotype was associated with a higher probability of developing overweight (44.7 versus 27.0%, P < 0.05) and a trend to higher blood pressure (52.6 versus 38.4%, P = 0.09) over 20 years. CONCLUSION: We conclude that the Trp64Arg variant of the beta3-AR receptor predicts a greater tendency to develop abdominal adiposity and high blood pressure with advancing age.

Adipose Tissue↗

Altered renal sodium handling in men with abdominal adiposity: a link to hypertension.

OBJECTIVES: Central adiposity, insulin resistance and hypertension are clearly interrelated but the mechanisms underlying this association have not been thoroughly elucidated. As renal sodium handling plays a central role in salt-sensitive forms of hypertension, we investigated the relation of renal tubular sodium handling to abdominal adiposity, blood pressure and insulin sensitivity. DESIGN: Population-based study. PARTICIPANTS: Five hundred and fifty-five untreated Olivetti male workers, aged 25-75 years. SETTING: Olivetti factory medical centers in Pozzuoli and Marcianise (Naples, Italy) MAIN OUTCOME MEASURES: Anthropometric indices, serum insulin, homeostatic model assessment index of insulin sensitivity, blood pressure, fractional excretions of uric acid and exogenous lithium (as markers of renal tubular sodium handling). RESULTS: In univariate analysis, measures of central adiposity (i.e. sagittal abdominal diameter and umbilical circumference) were directly correlated with serum insulin (P < 0.001) and blood pressure levels (P < 0.001) and inversely associated with the fractional excretions of uric acid and lithium (P = 0.01-0.001). In multiple linear regression analysis, the same anthropometric indices but not the measures of peripheral adiposity (arm circumference and tricipital skinfold thickness), were significant predictors of the fractional excretion of uric acid and lithium, independently of age, blood pressure and serum insulin levels (P = 0.01-0.001). CONCLUSIONS: Abdominal adiposity was associated with altered renal tubular sodium handling apart from insulin resistance and high blood pressure. The data indicate that men with prevalent abdominal adiposity have an enhanced rate of tubular sodium reabsorption, mainly at proximal sites. These findings provide a possible mechanistic link between central adiposity and salt-dependent hypertension.

Abdomen↗

Correlates of compliance in a randomized exercise trial in myocardial infarction patients.

PURPOSE: Exercise-based rehabilitation programs have been associated with decreased morbidity and mortality after myocardial infarction. Unfortunately, attendance is often poor, and information is limited regarding predictors of long-term compliance to such programs. This study examined factors associated with exercise session compliance over 3 yr in male myocardial infarction (MI) survivors. METHODS: Subjects were participants in the National Exercise and Heart Disease Project, a 3-yr (1976-1979) multicenter, randomized clinical trial (N = 651); 308 men, 30-64 yr of age, were randomized to the exercise treatment group, that met three times/week throughout the study. Compliance was defined as the number of sessions attended/number of sessions conducted. Patient characteristics at enrollment were considered as possible predictors of compliance. RESULTS: Compliance decreased as time since enrollment increased with the largest decrease observed after the first 8 wk. Compliance correlated positively with exercise test measures [last completed stage (r = 0.17, P < 0.01), peak heart rate (r = 0.11, P = 0.06)], high density lipoprotein (HDL) cholesterol (r = 0.15, P = 0.10), age (r = 0.11, P = 0.07), and inversely with body mass index (r = -0.19, P = 0.001), sum of three skinfolds (r = -0.15, P < 0.01), total cholesterol (r = -0.18, P < 0.01), triglycerides (r = -0.16, P < 0.01), and depression (r = -0.09, P < 0.11). Current smokers were less compliant than former and nonsmokers (r = -0.21, P < 0.001). The correlations with last completed stage, BMI, skinfolds, total cholesterol, and smoking status were statistically significant. The model explained 22.2% of the variance in compliance (r2 = 0.222). Baseline work capacity was among the most consistent predictors of early and late compliance. CONCLUSION: Compliance decreased over time. Men already at high risk for repeat events due to elevated risk factors were less compliant. These findings have important clinical implications regarding screening, intervention, and participation in potential cardiac rehabilitation program dropouts.

Adult↗

Measurement variability of plasma beta-sitosterol and campesterol, two new biomarkers for cancer prevention.

Phytosterols are plant sterols that are structurally similar to cholesterol and are characterized by anti-carcinogenic and anti-atherogenic properties. Beta-sitosterol and campesterol are the predominant phytosterols in blood. The present study aimed to analyse the reproducibility and overtime reliability of plasma beta-sitosterol and campesterol measurements. In order to study the reproducibility of the measurement (technical variability), three healthy premenopausal women donated a sample of their blood. Each blood sample was subdivided into six aliquots and analysed within the same run by the same laboratory technician. The intraclass correlation coefficients (ICCs) of the assay for plasma beta-sitosterol and campesterol were 0.88 and 0.94 (95% confidence intervals low bounds (95% CI(low)) were 0.66 and 0.82), respectively. To study the reliability of beta-sitosterol and campesterol measurement over time, seven premenopausal women were recruited. Over a 6-month period, each woman provided a fasting blood sample once a month at the same time of day, and the same numerical day of the luteal phase of her menstrual cycle (between the 20th and 24th day of her menstrual cycle). All plasma samples from the same individual were processed together at the same time by the same technician at the end of the 6-month period. The overtime ICCs of plasma beta-sitosterol and campesterol were 0.91 (95% CI(low) 0.49) and 0.58 (95% CI(low) 0.31), respectively. The high reproducibility and good overtime reliability of plasma beta-sitosterol and campesterol measurements indicate that they may be suitable for potential clinical and population-based studies on cancer prevention.

Adult↗

The relation of serum levels of antioxidant vitamins C and E, retinol and carotenoids with pulmonary function in the general population.

Reduced pulmonary function is an important predictor of mortality in the general population, and antioxidant vitamins are thought to positively influence pulmonary function. Vitamin C, vitamin E, retinol, and carotenoids are powerful antioxidants but information about the joint relation of serum levels of these antioxidants to pulmonary function is limited. We analyzed the association of FEV(1) and FVC with serum vitamins C and E, retinol, and carotenoids (beta-cryptoxanthin, lutein/zeaxanthin, beta-carotene, and lycopene) in a cross-sectional study. The analysis was carried out in a sample of 1,616 randomly selected residents of Western New York, USA, age 35 to 79 yr and free of respiratory disease. Lung function was adjusted for height, age, sex, and race and expressed as percentage of predicted normal FEV(1) (FEV(1)%) and FVC (FVC%). Participants in the lowest quartile of each of the serum antioxidants had consistently lower FEV(1)% and FVC% than those in higher quartiles. Multiple linear regression analysis revealed significant associations of vitamin C, vitamin E, beta-cryptoxanthin, lutein/zeaxanthin, beta-carotene, and retinol with FEV(1)% when these variables were investigated individually after adjustment for other covariates (smoking status, pack-years of smoking, weight, eosinophil count, and education). When all of these antioxidant vitamins were analyzed simultaneously in a multivariate regression model, the strongest association was seen with vitamin E and beta-cryptoxanthin. Only retinol showed an independent effect on FEV(1)% after controlling for vitamin E and beta-cryptoxanthin. As for FEV(1)%, vitamin E and beta-cryptoxanthin were most strongly related to FVC% when all variables were considered in the multivariate regression model. The differences in FEV(1) associated with a reduction of one standard deviation of serum vitamin E or beta-cryptoxanthin were equivalent to the negative influence of approximately 1 to 2 yr of aging. Our findings support the hypothesis that antioxidant vitamins may play a role in respiratory health and that vitamin E and beta-cryptoxanthin appear to be stronger correlates of lung function than other antioxidant vitamins.

Adult↗

TBARS and cardiovascular disease in a population-based sample.

BACKGROUND: Oxygen radicals might play a crucial role in the pathogenesis of various diseases, including atherosclerosis. Thiobarbituric acid reaction substances (TBARS), a biomarker of oxidative stress, have been proposed as a summary measure of total circulating oxidation. However, there is no strong indication that circulating levels of TBARS are increased in patients with atherosclerosis. DESIGN: We evaluated the relation between TBARS and cardiovascular disease (CVD) in a cross-sectional random sample of white men and women from Buffalo, New York. METHODS: Logistic regression was used to estimate the risk associated with high levels of TBARS. The area under the ROC curve was used to evaluate the discriminating power of TBARS. RESULTS: After adjusting for age and gender, TBARS levels were significantly higher in those with prevalent CVD (OR= 1.73, 95% CI=1.32-2.38), compared to those without a CVD diagnosis. These OR were almost 50% higher after correcting for measurement error (ME) (OR=1.93, 95% CI=1.07-3.40). The area under the ROC curve was 0.69 (95% CI=0.62-0.77) and when corrected for ME reached 0.80 (95% CI=0.65-0.89). CONCLUSIONS: Our results indicate that elevated levels of TBARS were associated with increase risk of the prevalence of CVD, but this effect was no longer significant after adjusting for glucose.

Adult↗

Periodontal infections contribute to elevated systemic C-reactive protein level.

BACKGROUND: Periodontitis is a local inflammatory process mediating destruction of periodontal tissues triggered by bacterial insult. However, this disease is also characterized by systemic inflammatory host responses that may contribute, in part, to the recently reported higher risk for cardiovascular disease (CVD) among patients with periodontitis. Moderate elevation of C-reactive protein (CRP) has been found to be a predictor of increased risk for CVD. Elevated CRP levels in periodontal patients have been reported by several groups. In this study, we examined whether CRP plasma levels are increased in periodontitis and if there is a relation to severity of periodontal disease and to the periodontal microflora. METHODS: CRP serum levels were assessed using radial immunodiffusion assay in 174 subjects, 59 with moderate mean clinical attachment loss (AL) (2.39+/-0.29 mm) and 50 with high AL (3.79+/-0.86 mm) as compared to 65 periodontally healthy controls (AL, 1.74+/-0.18 mm). Clinical attachment loss, probing depths, and percentage of periodontal pocket sites > or =5 mm were measured. The presence of periodontal pathogens Porphyromonas gingivalis (P.g.), Prevotella intermedia (P.i.), Campylobacter recta (C.r.), and Bacteroides forsythus (B.f.) in subgingival plaque samples was measured by immunofluorescence microscopy. RESULTS: Statistically significant increases in CRP levels were observed in subjects with periodontal disease when compared to healthy controls (P= 0.036). Subjects with high levels of mean clinical attachment loss had significantly higher mean CRP levels (4.06+/-5.55 mg/l) than controls (1.70+/-1.91 mg/l), P= 0.011. The CRP levels were adjusted for factors known to be associated with elevated CRP, including age, smoking, body mass index (BMI), triglycerides, and cholesterol. Age and BMI were found to be significant covariates. The reported range for CRP as a risk factor for CVD, peripheral vascular diseases, or stroke is 1.34 mg/l to 6.45 mg/l and the mean of this range is 3 mg/l. The percentage of subjects with elevated levels of CRP > or = 3 mm was significantly higher in the high clinical AL group (38%; 95% Cl: 26.7%, 49.3%) when compared to the control group (16.9%; 95% CI: 9.25%, 24.5%), P= 0.011. The presence of periodontal pathogens P.g., P.i., C.r., and B.f. in subgingival samples was positively associated with elevated CRP levels (P= 0.029). CONCLUSIONS: The extent of increase in CRP levels in periodontitis patients depends on the severity of the disease after adjusting for age, smoking, body mass index, triglycerides, and cholesterol. Also, there are elevated levels of CRP associated with infection with subgingival organisms often associated with periodontal disease, including P.g., P.i., C.r., and B.f. Recent investigations emphasized the role of moderate elevated CRP plasma levels as a risk factor for CVD. The positive correlation between CRP and periodontal disease might be a possible underlying pathway in the association between periodontal disease and the observed higher risk for CVD in these patients.

Adult↗

Markers of insulin resistance and colorectal cancer mortality.

A link between insulin metabolism and colorectal cancer has been hypothesized, supported by a series of potential physiological mechanisms, and confirmed by a number of reports in experimental animals. However, the evidence in humans is limited and mostly indirect. The aim of the present report is to analyze whether individuals with a cluster of metabolic abnormalities associated with abnormalities in insulin metabolism experience higher mortality for colorectal cancer than those without this cluster of metabolic abnormalities. A total of 21,311 men and 15,991 women 20-69 years of age were followed-up for an average of 7 years as part of the Risk Factors and Life Expectancy Project, a pooling of a number of epidemiological studies conducted in Italy. Our analyses indicate that participants with high levels of blood glucose and a cluster of metabolic abnormalities linked to insulin resistance experienced a significant increased risk of colorectal cancer mortality compared with participants without the cluster. For the presence of the cluster of metabolic abnormalities, the calculated hazard ratios and 95% CIs were 2.96 (1.05-8.31) for men, 2.71 (0.59-12.50) for women, and 2.99 (1.27-7.01) when both sexes were combined. These associations were independent from the potential confounding effect of age, drinking of alcoholic beverages, and smoking. Our findings are supportive of the hypotheses that glucose metabolism hyperinsulinemia, insulin resistance, and metabolic abnormalities associated with it may play a significant role in the etiology of colorectal cancer.

Adult↗

Periodontal disease and risk of cerebrovascular disease: the first national health and nutrition examination survey and its follow-up study.

BACKGROUND: Periodontal disease has been found to be a potential risk factor for coronary heart disease. However, its association with cerebrovascular accidents (CVAs) is much less studied. METHODS: This study examines the association between periodontal disease and CVA. The study cohort comprises 9962 adults aged 25 to 74 years who participated in the First National Health and Nutrition Examination Survey and its follow-up study. Baseline periodontal status was categorized into (1) no periodontal disease, (2) gingivitis, (3) periodontitis, and (4) edentulousness. All CVAs (International Classification of Diseases, Ninth Revision [ICD-9], codes 430-438) were ascertained by hospital records for nonfatal events and death certificates for fatal events. The first CVA, nonfatal or fatal, was used to define incidence. Relative risks were estimated by hazard ratios from the Cox proportional hazard model with adjustment for several demographic variables and well-established cardiovascular risk factors. Weights were used to generate risk estimates. RESULTS: Periodontitis is a significant risk factor for total CVA and, in particular, nonhemorrhagic stroke (ICD-9, 433-434 and 436-438). Compared with no periodontal disease, the relative risks (95% confidence intervals) for incident nonhemorrhagic stroke were 1.24 (0.74-2.08) for gingivitis, 2.11 (1.30-3.42) for periodontitis, and 1.41 (0.96-2.06) for edentulousness. For total CVA, the results were 1.02 (0.70-1.48) for gingivitis, 1.66 (1.15-2.39) for periodontitis, and 1.23 (0.91-1.66) for edentulousness. Increased relative risks for total CVA and nonhemorrhagic stroke associated with periodontitis were also seen in white men, white women, and African Americans. Similar results were found for fatal CVA. CONCLUSION: Periodontal disease is an important risk factor for total CVA and, in particular, nonhemorrhagic stroke.

Adult↗

Arterial abnormalities in the offspring of patients with premature myocardial infarction.

BACKGROUND: Findings from epidemiologic and autopsy studies suggest that the offspring of patients with premature coronary disease may be at increased risk for atherosclerosis. We undertook a study to determine whether changes in brachial-artery reactivity and thickness of the carotid intima and media, two markers of early atherosclerosis, are present in adolescents and young adults with a parental history of premature myocardial infarction. METHODS: We enrolled 40 healthy young people whose parents had had premature myocardial infarction (48 percent male; mean [+/-SD] age, 19.0+/-5.2 years) and 40 control subjects who were matched with the first group according to age and sex. All the subjects underwent high-resolution B-mode ultrasound examinations for the measurement of the brachial-artery vasodilatory response after arterial occlusion (i.e., reactive hyperemia) and the intima-media thickness of the distal common carotid arteries. Lipid profiles, blood pressure while at rest, body-mass index, and smoking status were also determined. RESULTS: As compared with the control subjects, the offspring of patients with premature myocardial infarction had lower flow-mediated reactivity of the brachial arteries (5.7+/-5.0 percent, vs. 10.2+/-6.6 percent in the control subjects; P=0.001) and greater mean intima-media thickness of the common carotid artery (0.49+/-0.08 mm, vs. 0.44+/-0.07 mm in the control subjects, P=0.004). In the subjects with a parental history of premature myocardial infarction, an inverse association was found between brachial-artery reactivity and carotid intima-media thickness (r=-0.46, P=0.003). In a conditional logistic-regression analysis, both brachial-artery reactivity and carotid intima-media thickness were significantly and independently correlated with a parental history of premature myocardial infarction. CONCLUSIONS: Structural and functional changes are present at an early age in the arteries of persons with a parental history of premature myocardial infarction.

Adolescent↗

Long term relations between earthquake experiences and coronary heart disease risk factors.

The authors analyzed the relations between a variety of earthquake-related experiences incurred in 1983-1984 (financial loss, evacuation, indices of disruption of social networks) and coronary heart disease risk factors (heart rate, blood pressure, total serum cholesterol) assessed in 1987 among 693 Italian male factory workers. Multivariate analyses (adjusting for age, body mass index, smoking, and educational level) revealed no long term relations between the quake-related experiences and blood pressure or cholesterol level. However, higher resting heart rates were observed for individuals who reported financial loss, increased distance from family/friends, or decreased visiting as a result of relocation after the quakes. Findings were unchanged after further adjustment for self-reported psychological distress (assessed using the global symptom index of the Symptom Checklist). These findings, while limited by the cross-sectional nature of the data, suggest that a number of psychosocial consequences of relocation due to a natural disaster are unrelated in the long term to coronary heart disease risk factors, except for small but significant differences in heart rate among individuals who have experienced financial loss and/or social network disruptions.

Adult↗

Examination of the relation between periodontal health status and cardiovascular risk factors: serum total and high density lipoprotein cholesterol, C-reactive protein, and plasma fibrinogen.

Using data from the Third National Health and Nutrition Examination Survey (1988-1994), the authors examined the relation between periodontal health and cardiovascular risk factors: serum total and high density lipoprotein cholesterol, C-reactive protein, and plasma fibrinogen. A total of 10,146 participants were included in the analyses of cholesterol and C-reactive protein and 4,461 in the analyses of fibrinogen. Periodontal health indicators included the gingival bleeding index, calculus index, and periodontal disease status (defined by pocket depth and attachment loss). While cholesterol and fibrinogen were analyzed as continuous variables, C-reactive protein was dichotomized into two levels. The results show a significant relation between indicators of poor periodontal status and increased C-reactive protein and fibrinogen. The association between periodontal status and total cholesterol level is much weaker. No consistent association between periodontal status and high density lipoprotein cholesterol was detectable. Similar patterns of association were observed for participants aged 17-54 years and those 55 years and older. In conclusion, this study suggests that total cholesterol, C-reactive protein, and fibrinogen are possible intermediate factors that may link periodontal disease to elevated cardiovascular risk.

Adolescent↗

Nonpoint-source agricultural hazard index: a case study of the province of cremona, Italy.

This paper reports the results of a study aimed at the evaluation of the hazard level of farming activities in the province of Cremona, Italy, with particular reference to groundwater. The applied methodology employs a parametric approach based on the definition of potential hazard indexes (nonpoint-source agricultural hazard indexes, NPSAHI). Two categories of parameters were considered: the hazard factors (HF), which represent all farming activities that cause or might cause an impact on groundwater (use of fertilizers and pesticides, application of livestock and poultry manure, food industry wastewater, and urban sludge), and the control factors (CF), which adapt the hazard factor to the characteristics of the site (geographical location, slope, agronomic practices, and type of irrigation). The hazard index (HI) can be calculated multiplying the hazard factors by the control factors and, finally, the NPSAHI are obtained dividing HI into classes on a percentile basis using a scale ranging from 1 to 10. Organization, processing, and display of all data layers were performed using the geographical information system (GIS) ArcView and its Spatial Analyst extension. Results show that the potential hazard of groundwater pollution by farming activities in the province of Cremona falls mainly in the fifth class (very low hazard).

Journal Article↗

The effect upon the human vaginal histology of the long-term use of the injectable contraceptive Depo-Provera.

The objective of the study was to evaluate the effect of long-term use of the injectable contraceptive depot medroxyprogesterone acetate (DMPA) on human vaginal histology. Twenty premenopausal women currently using DMPA as a contraceptive method for two and three years were compared with 20 regularly menstruating women, who never used Depo-Provera and/or other kind of hormonal contraceptive in the last 6 months prior to the study. Subjects and controls were matched by age (+/-1 year), body mass index (kg/m2) (+/-1.0), number of pregnancies (+/-1), age at first intercourse (+/-1 year), years of sexual activity (+/-1 year), and number of partners during their life (+/-1). Vaginal biopsies were performed in users at 90+/-7 days after the last injection and in nonusers at day 20-25 of the menstrual cycle. In addition, at the day of the biopsy a blood sample was collected to measure estradiol (in all women) and DMPA in users. The level of serum estradiol was significant lower in Depo-Provera users than in controls (p < 0.001). The thickness of the vaginal epithelium was not smaller among DMPA users than among controls, the mean count of Langerhans cells per mm of epithelium were almost identical in both groups, and no significant differences were found on the vaginal maturation indices. In conclusion, the use of Depo-Provera between two and three years did not affect vaginal thinning of the epithelium, Langerhans cell count or maturation index.

Adult↗

Short-term storage of blood samples and DNA isolation in serum separator tubes for application in epidemiological studies and clinical research.

PURPOSE: To investigate the use of a simple DNA isolation technique for application in epidemiologic studies. To analyze systematically the potential impact of lag time between blood drawing and DNA isolation and the condition of storage of blood samples on the quantity and quality of isolated DNA in large-scale epidemiologic studies. METHODS: A modified single tube DNA isolation technique was used. DNA was isolated from samples collected from six participants and processed in triplicate: a) without delay after blood drawing; b) after blood cells were stored at 4 degrees C for 7 days; c) after blood cells were stored at -70 degrees C for 7 days; and d) after storage for 7 days at -70 degrees C with addition of lysis/digestion buffer. Polymerase chain reaction (PCR) and Southern blot analysis were performed to analyze the quality of the isolated DNA. RESULTS: The average amount of DNA isolated ranged from 27.0 to 71.1 microg/4.5 ml whole blood. Storage at 4 degrees C yielded, on the average, 20% less DNA than the samples processed without delay or after storage at -70 degrees C, although this difference was not statistically significant. All four conditions studied allowed isolation of highly pure DNA suitable for genetic analyses by Southern blot analysis and polymerase chain reaction. CONCLUSIONS: This pilot study suggests that storage for 7 days and at different temperatures allows isolation of high quality DNA. Using the described technique, storage of up to 7 days permits processing of large numbers of samples (50-70) in a single day, allowing for a reliable and cost-efficient way of processing in various settings. Further studies are needed to investigate the influence of long-term storage of biological specimens on DNA isolation and quality.

Blood Banks↗

Markers of insulin resistance and sex steroid hormone activity in relation to breast cancer risk: a prospective analysis of abdominal adiposity, sebum production, and hirsutism (Italy).

OBJECTIVE: Insulin resistance and increased levels of serum steroids have been hypothesized to be relevant etiological factors for breast cancer. Measurements of markers of insulin resistance and elevated serum steroids may identify women at high risk for breast cancer. The present study analyzed the association of breast cancer with markers of insulin resistance and elevated serum sex steroids, abdominal adiposity, increase in sebum production and hirsutism in a case-control study nested in a prospective cohort study. METHODS: Between 1987 and 1992, 10,786 women (aged 35-69) were recruited in a prospective study on breast cancer in Italy, the ORDET study. Women with a history of cancer and on hormone therapy were excluded at baseline. At recruitment, abdominal adiposity was calculated from the ratio of waist-to-hip circumferences. Sebum production was measured on the forehead under standardized conditions using a sebumeter. Nine androgen-sensitive body areas were evaluated for hirsutism and a total hirsutism score was computed. After an average of 5.5 years of follow-up, 144 breast cancer cases were identified among the participants of the cohort. For each breast cancer case, four matched controls were randomly chosen from members of the cohort who did not develop breast cancer during the follow-up period. RESULTS: Waist-to-hip ratio was associated with breast cancer in premenopausal women: age and body mass index (BMI) adjusted relative risk (RR) for the highest tertile of waist-to-hip ratio was 2.2 [95% confidence interval (CI) 1.04-4.75], p for trend 0.03. In the analysis conducted within strata of BMI, the effect of waist-to-hip ratio was confined to the group of thinner women: RR for the highest tertile of waist-to-hip ratio was 3.4 (95% CI 1.2-9.5). Sebum production and hirsutism were associated with breast cancer among postmenopausal women. Age and BMI adjusted RRs for the upper tertiles were 2.2 (95% CI 1.1-4.6), p for trend 0.01, and 2.3 (95% CI 1.1-4.9), p for trend 0.03, for sebum and hirsutism, respectively. CONCLUSION: These results add evidence for a role of hormones and metabolic alterations in breast cancer etiology and for different relations of these risk factors with breast cancer in premenopausal and postmenopausal women.

Abdomen↗