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PubMed1977

Anthropometric determination of body volume, body density and segmental volume in adult Indian women.

Body density, total body volume, leg volume and arm volume of 65 young Indian women 20-25 years were measured experimentally. In addition, a series of 61 anthropometric measurements were also taken on each subject. Correlations of leg volume with total body volume and body density were 0.91 and -0.73 respectively and of arm volume with total body volume and body density were 0.84 and -0.66 respectively. Hip girth alone showed a very high positive correlation (r = 0.94) with body volume and on selective stepwise multiple regression analysis, a combination of even four anthropometric measurements, namely, hip girth, lower thigh girth, ankle girth and shoulder diameter gave an extremely high positive multiple correlation coefficient (R = 0.98) with body volume. Selective stepwise multiple linear regression analysis was conducted also to estimate leg volume, arm volume and body density and stepwise regression equations up to 4th step for estimating each parameter are given.

Adult↗

PubMed2002

The morning surge in blood pressure and heart rate is dependent on levels of physical activity after waking.

OBJECTIVE: To define the influence of morning physical activity levels on the magnitude of the morning surge in blood pressure and heart rate. DESIGN AND METHODS: Blood pressure and physical activity were simultaneously recorded in 420 patients by 24-h monitor and actigraphy. The morning surge was defined as the difference between mean blood pressure and heart rate values in the 4-h periods before and after waking; the trough-to-peak surge in blood pressure was also calculated. These values were regressed on the difference in mean (log transformed) physical activity for the same two periods. The analysis was adjusted for covariates, including age, sex, clinic blood pressure and use of antihypertensive medication, in a multiple linear regression. RESULTS: The mean morning surges in blood pressure and heart rate were 23/15(+/- 13/10) mmHg and 17(+/- 10) beats/min, respectively. The geometric mean increase in physical activity after waking was 33(+/- 1.5) units. The magnitudes of the morning surge in systolic blood pressure, diastolic blood pressure and heart rate were all significantly and positively correlated with the difference in mean physical activity before and after waking (P < 0.005). Greater clinic blood pressure was significantly associated with a greater morning surge in blood pressure on physical activity (P < 0.0005). CONCLUSIONS: The magnitude of the morning surge is significantly associated with the level of physical activity in the hours after waking. Physical activity should be taken into account when the results of ambulatory blood pressure monitoring are interpreted.

Adolescent↗

PubMed1995

Delay in neurological attention and stroke outcome. Cerebrovascular Diseases Study Group of the Spanish Society of Neurology.

BACKGROUND AND PURPOSE: Despite efforts to reduce the delay between stroke onset and new interventional treatments, no studies have analyzed the repercussions of early neurological attention on the clinical outcome of stroke patients. METHODS: Data were obtained from 721 patients admitted consecutively for a transient ischemic attack or stroke to the neurology departments of 18 Spanish hospitals that followed the same diagnostic and therapeutic guidelines in the acute phase. Factors assessed were age, sex, Canadian Stroke Scale score on admission, previous Barthel Index, and delay before attention by the first physician, by emergency services, by a neurologist, and before hospitalization. Patients' outcomes were classified as good (Barthel Index > 60) or poor (Barthel Index < or = 60 or in-hospital death) depending on patient's functional capacity on discharge. The individual contribution of each of these variables on clinical outcome was estimated with logistic regression analysis. RESULTS: Patients in worse neurological condition on admission presented earlier to the first physician, emergency department, and neurologist. The mortality rate was not significantly modified by early or late presentation at the different medical stages. Logistic regression analysis revealed that the relative risk of poor outcome in patients seen by the neurologist after the first 6 hours from symptom onset was 5.6 (95% confidence interval, 3.4 to 9.2) (P < .0001). Multiple linear regression analysis showed that the delay before the patient received neurological attention correlated positively with the duration of hospitalization (P < .0001). The delays before the patient was seen by the first physician or the emergency department and before hospitalization were not independently related to clinical outcome or length of hospitalization. CONCLUSIONS: Early neurological attention in acute stroke is related to better functional outcome and shorter hospitalization.

Age Factors↗

PubMed2004

Association of obesity with inflammation in chronic kidney disease: a cross-sectional study.

OBJECTIVE: As adipose tissue releases inflammatory cytokines, obesity is associated with elevated C-reactive protein (CRP) levels in the general population. We examined the cross-sectional association of body mass index (BMI) with CRP in patients with chronic kidney disease (CKD). DESIGN: Cross-sectional study. SETTING AND PARTICIPANTS: Ninety-four CKD patients with varying levels of renal function seen at the University of Utah outpatient renal clinic were studied. METHODS: Data on demographics (age, gender, race), comorbidity (diabetes mellitus, hypertension, myocardial infarction/angina, cerebrovascular disease, peripheral vascular disease, and smoking) and anthropometry (height and weight) were obtained by patient interview and chart reviews. High-sensitivity CRP was measured by the N-latex assay on a BN II nephelometer. MAIN OUTCOME MEASURE: Risk factors of high CRP. RESULTS: In a multivariable logistic regression model, when compared with patients with a BMI < 25, the odds of CRP > 3.0 mg/L were 2.5-fold (95% CI, 1.02 to 5.99) higher in patients with BMI > or = 30. In a stepwise multiple linear regression model, BMI (regression coefficient [beta] = 0.06; 95% CI, 0.03 to 0.1; P < .01), serum creatinine (beta = 0.16; 95% CI, 0.04 to 0.3; P = .01) and age (beta = 0.01; 95% CI, -0.001 to 0.03; P = .05) were significantly associated with log transformed CRP. CONCLUSION: These data suggest that as in the general population, in CKD patients, obesity, a traditional risk factor for atherosclerosis, is associated with inflammation, a novel risk factor for atherosclerosis.

Adult↗

PubMed2006

Acute health effects of the Tasman Spirit oil spill on residents of Karachi, Pakistan.

BACKGROUND: On July 27 2003, a ship carrying crude oil ran aground near Karachi and after two weeks released 37,000 tons of its cargo into the sea. Oil on the coastal areas and fumes in air raised health concerns among people. We assessed the immediate health impact of oil spill from the tanker Tasman Spirit on residents of the affected coastline in Karachi, Pakistan. METHODS: We conducted a study consisting of an exposed group including adults living in houses on the affected shoreline and two control groups (A and B) who lived at the distance of 2 km and 20 km away from the sea, respectively. We selected households through systematic sampling and interviewed an adult male and female in each household about symptoms relating to eyes, respiratory tract, skin and nervous system, smoking, allergies, beliefs about the effect on their health and anxiety about the health effects. We used logistic regression procedures to model each symptom as an outcome and the exposure status as an independent variable while adjusting for confounders. We also used linear regression procedure to assess the relationship exposure status with symptoms score; calculated by summation of all symptoms. RESULTS: Overall 400 subjects were interviewed (exposed, n = 216; group A, n = 83; and group B, n = 101). The exposed group reported a higher occurrence of one or more symptoms compared to either of the control groups (exposed, 96% vs. group A, 70%, group B 85%; P < 0.001). Mean summary symptom scores were higher among the exposed group (14.5) than control group A (4.5) and control group B (3.8, P < 0.001). Logistic regression models indicated that there were statistically significant, moderate-to-strong associations (Prevalence ORs (POR) ranging from 2.3 to 37.0) between the exposed group and the symptoms. There was a trend of decreasing symptom-specific PORs with increase in distance from the spill site. Multiple linear regression model revealed strong relationship of exposure status with the symptoms score (beta = 8.24, 95% CI: 6.37-10.12). CONCLUSION: Results suggest that the occurrence of increased symptoms among the exposed group is more likely to be due to exposure to the crude oil spill.

Adolescent↗

PubMed2001

Linear regression and computational neural network prediction of tetrahymena acute toxicity for aromatic compounds from molecular structure.

A quantitative structure toxicity relationship (QSTR) has been derived for a diverse set of 448 industrially important aromatic solvents. Toxicity was expressed as the 50% growth impairment concentration (ICG(50)) for the ciliated protozoa Tetrahymena and spans the range -1.46 to 3.36 log units. Molecular descriptors that encode topological, geometrical, electronic, and hybrid geometrical-electronic structural features were calculated for each compound. Subsets of molecular descriptors were selected via a simulated annealing technique and a genetic algorithm. From this reduced pool of descriptors, multiple linear regression models and nonlinear models using computational neural networks (CNNs) were derived and then used to predict the ICG(50) values for an external set of representative compounds. An average of 10 nonlinear CNN models with 11-5-1 architecture was found to best describe the system with root-mean-square errors of 0.28, 0.29, and 0.34 log units for the training, cross validation, and prediction sets, respectively.

Animals↗

PubMed1994

Studies in hypertriglyceridaemia. 1. Serum triglyceride distribution and its correlates in randomly selected Swedish middle-aged men.

OBJECTIVES: To obtain a randomly selected hypertriglyceridaemic population for detailed further characterization. DESIGN: Study of randomly selected males. SETTING: Subjects examined and blood sampled at Sollentuna Primary Health Care Centre. SUBJECTS: Men aged 40-50 years (n = 1564), living in the Stockholm area, who were screened for hypertriglyceridaemia, January 1990-June 1992. MAIN OUTCOME MEASURES: Fasting concentrations of serum triglycerides. RESULTS: The serum triglyceride concentration distribution showed the expected skew distribution with the 90th and the 95th percentile at 2.51 and 3.05 mmol L-1, respectively. The mean serum triglyceride level compared well with several population values reported from this laboratory over the last 30 years, indicating stable triglyceride levels over time. There was no significant age-trend for the triglyceride concentration. Lower mean values for triglyceride, insulin and waist-to-hip (W/H) ratio were observed during the summer, whilst apolipoprotein A-I levels were higher. There was a linear relation between the number of cigarettes smoked and the serum triglyceride concentration. In stepwise multiple linear regression analysis with the triglyceride concentration as the dependent variable the following variables appeared as significant (P < 0.01) contributors: insulin, cholesterol, glucose, apolipoprotein A-I, number of cigarettes smoked, BMI, W/H ratio and diastolic blood pressure. The regression coefficient for apolipoprotein A-I was negative; all the others were positive. The multiple regression (R) was 0.68, suggesting that up to 47% of the variation of the serum triglyceride concentration could be predicted by these factors. CONCLUSIONS: A group of randomly selected hypertriglyceridaemic men has been recruited for further clinical, metabolic and genetic studies. Basic characteristics of the population for their recruitment are described.

Adult↗

PubMed1980

An electrocardiographic estimation of the left and right ventricular weight of the heart. Regression analysis based on the deviation from normal standards.

The deviation of the electrocardiographic deflections from normal standards and a grading of the ST segments were obtained from the ECGs of subjects who were subsequently examined by cardiac partitioning at autopsy. A stepwise, multiple, linear regression analysis was calculated, where the ventricular weights were the determinate variables, and the electrocardiographic deviation from normal standards, the grading of the ST segments, age and weight were the indeterminate variables. The results for the entire series of cases and subgroups were statistically significant at P less than 0,001. The wide spectrum of left and right ventricular weights required the establishment os subgroups, in which the variation in ventricular weight explained by the indeterminate variables was of a high order. The results were similar to estimations based on the actual electrocardiographic measurements rather than on their deviation from normal standards.

Cardiomegaly↗

PubMed2005

The inverse relationship between thoracic aortic intima media thickness and testosterone level.

BACKGROUND: It is known that testosterone prevents coronary artery disease, and lower testosterone level is a risk factor for ischemic heart disease in men. However, there is no report showing the relationship between testosterone level and severity of thoracic aortic atherosclerosis. AIM: To investigate whether a relationship exists between atherosclerotic thoracic aortic intima media thickness (TAIT) and testosterone level. METHOD: Forty-two male patients (mean age 56 +/- 12 years) without a history of atherosclerotic cardiovascular disease referred for transesophageal echocardiography (TEE) were included. Intima media thickness of aorta was evaluated in each patient by using TEE. Testosterone levels were measured using a commercial kit. Blood chemistry parameters were measured by automated analyzers. The data obtained was evaluated by using correlation analyses and linear regression analysis tests. RESULTS: Mean testosterone values were 507 +/- 209 ng/dl. Testosterone levels showed a negative significant correlation with TAIT (r = -765, p < 0.001). In addition, testosterone levels showed positive correlations with albumin (r = 0.690, p = 0.019) and negative correlations with uric acid (r = -0.630, p < 0.001), HsCRP (r = -0.449, p = 0.003), fibrinogen (r = -0.508, p = 0.001), and white blood cells (r = -0.433, p = 0.005). On the other hand, multiple linear regression analysis showed that TAIT was independently associated with testosterone and uric acid (beta = -0.610, p = 0.002 versus beta = 0.409, p = 0.026 respectively). CONCLUSION: This study indicates that there is an independent relationship between testosterone and TAIT.

Adult↗

PubMed1986

Retinopathy of prematurity: the influence of gestational age and retinal maturity on the statistical behavior of risk factors.

The clinical and laboratory data on 140 premature infants, 74 cases with retinopathy of prematurity (ROP) and 66 control cases without ROP, were correlated with ROP grades of increasing severity. By using multiple linear regression (MLR), it is shown that for predicting ROP grades the importance of certain variables varies considerably depending on the gestational age. Below 32 weeks of gestation, acidosis, hyperoxemia, gestational age, pathologic paCO2 levels, and multiple birth are strong regressors. Above 31 weeks, the most important regressors are multiple birth and acidosis, while gestational age and duration of FiO2 greater than 0.4 are much less influential. Blood transfusions and artificial ventilation do not seem important in the MLR of either group. When ROP is regressed on the number of paO2 values above 100 torr and gestational age or on the number of paCO2 values above 50 torr and gestational age, the regression coefficients of these variables drop to near zero at a gestational age of about 32 weeks. This loss of weight of the two variables paO2 and paCO2 with increasing gestational age coincides with a comparable drop of the relative incidence of ROP and the relative incidence of immature retinal vessels. It is hypothesized that it is the proportion of infants with an immature retinal vasculature in populations of given gestational ages rather than the gestational age itself which is responsible for the widely varying importance of certain factors during the development of ROP.

Gestational Age↗

PubMed2006

Impact of obesity in the critically ill trauma patient: a prospective study.

BACKGROUND: Obesity has risen at an epidemic rate over the past 20 years in the US. To our knowledge, there is an absence of data evaluating the impact of obesity in the critically ill trauma patient. METHODS: Prospective data were collected on 1,167 patients admitted to the ICU over a 2-year period. Obesity was defined as a body mass index (calculated as weight [kg]/height [m(2)]) of 30 or higher. Outcomes analyzed included infection rate, hospital and ICU length of stay, and mortality. Multiple logistic regression was used to evaluate outcomes between obese and nonobese patients for infection (infection versus noninfection) and mortality (deceased versus not deceased). Continuous outcomes such as hospital and ICU lengths of stay were evaluated using multiple linear regression analyses. RESULTS: Sixty-two of 1,167 (5.3%) patients were obese. The majority (71%) of injuries in the study cohort were blunt. Although the majority of patients were men (76%), women (10% versus 4%) were more likely to be obese (p < 0.001). Obese patients had a more than twofold increase in risk of acquiring a bloodstream, urinary tract, or respiratory infection, or being admitted to the ICU (p < 0.001), after statistically controlling for age and Injury Severity Score. When controlling for diabetes, gender, obesity, age, COPD, and Injury Severity Score, obese patients were 7.1 times (95% CI, 2.06-8.9) more likely to die in the hospital. CONCLUSIONS: Obesity is associated with a substantial increase in morbidity and mortality in the critically ill trauma patient. Future studies are warranted in both the prevention of infection and intensive care management of the obese trauma patient.

Adult↗

PubMed2000

Water fluoridation, poverty and tooth decay in 12-year-old children.

AIM: To examine the influence of water fluoridation, and socio-economic deprivation on tooth decay in the permanent dentition of 12 year old children. SETTING: The North of England, fluoridated Newcastle and non-fluoridated Liverpool. A total of 6,638 children were examined. OUTCOME MEASURES: Multiple Regression analysis of fluoride status, mean electoral ward DMFT in 1992/93 and ward Townsend Scores from the 1991 census. RESULTS: Social deprivation and tooth decay were significantly correlated in areas with and without water fluoridation. Multiple linear regression showed a statistically significant interaction between ward Townsend score, mean DMFT and water fluoridation, showing that the more deprived the area the greater the reduction in tooth decay. At a Townsend score of zero (the English average) there was a predicted 37% reduction in decay in 12-year-olds in fluoridated wards. CONCLUSIONS: Tooth decay is strongly associated with social deprivation. The findings confirm that the implementation of water fluoridation has markedly reduced tooth decay in 12-year-old children and that socio-economic dental health inequalities are reduced.

Child↗

PubMed2001

Soy intake and the maintenance of peak bone mass in Hong Kong Chinese women.

Our previous study on bone health among premenopausal women showed that bone mass consolidation is attained by the early 30s, and small loss of spinal bone mineral density (SBMD) occurs soon after peak bone mass attainment. Recent interest has been shown in the potential beneficial effects of phytoestrogens on bone health. However, data are lacking, particularly in Asian women. This study aims to investigate the effect of soy isoflavones intake on the maintenance of peak bone mass in a cohort of 132 women aged 30-40 years who were followed up for 3 years. Baseline measurements of SBMD (L2-L4) were obtained using dual-energy X-ray densitometry, and dietary intake of soy foods and other key nutrients, including dietary calcium, were obtained through a quantitative food frequency method. Information on body measurements; physical activity (PA), weight-bearing activity in particular; age of menarche; and number of pregnancies were obtained at baseline. Repeated measurements of SBMD were obtained yearly for a further 3 years with an average follow-up time of 38 months. Analyses were performed on 116 subjects with at least three SBMD measurements (at baseline, 3-year follow-up, and at least one measurement during follow-up). The individual SBMD regression slope was computed for each of the subjects. Soy isoflavones consumption was categorized as quartiles of intake. We observed a significant difference in the SBMD individual regression slopes between women belonging to the fourth and first soy isoflavones intake quartiles. The positive effect of soy isoflavones on SBMD remained after adjusting for age and body size (height, weight, and bone area). Multiple linear regression analysis including the other known covariates (lean body mass, PA, energy adjusted calcium, and follow-up time) showed that soy isoflavones, together with these variables, accounted for 24% of the variances of the SBMD individual regression slope. This longitudinal study shows that soy intake had a significant effect on the maintenance of SBMD in women aged 30-40 years. The effects of phytoestrogens on bone health should be explored further in a population with habitual dietary soy but low calcium intake.

Absorptiometry, Photon↗

PubMed1993

Multivariate influence of polyinositols on IP3 in diaphragm: individually applied matrix and vectorial analysis of trauma from small and large body surface area burn groups.

In this report, we have used multivariate and vectorial analyses to aid in understanding perturbations in diaphragmatic signal transduction in consequence to burn trauma. This trauma results from shock emanating from skin scald burn. Its respiratory complications are well-known. Relational matrices derived from experimental animal groups of varying body surface area (% BSA) burn size were subjected to individual multiple linear regression and vectorial analyses. Such individual matrices tested the simultaneous dependency of inositol 1,4,5-triphosphate (IP3) on inositol 1,4-biphosphate (I1,4P2), inositol 1-phosphate (I1P) and inositol. Understanding the contribution of multiple independent parameters simultaneously co-governing the dependency of IP3 offers new insight in regulating signal transduction mechanisms under the duress of burn trauma.

Analysis of Variance↗

PubMedDate not supplied

Vitamins A and E, retinol binding protein and zinc in rheumatoid arthritis.

Serum vitamins A (2.0 +/- 0.7 mumol/l; p less than 0.05) and E (17.7 +/- 8.2 mumol; p less than 0.001) levels were lower in patients with rheumatoid arthritis (RA) than in healthy controls (2.3 +/- 0.6 mumol/l and 25.3 +/- 5.4 mumol/l, respectively). Low vitamin A and E levels together with a marginally lowered selenium concentration may lead to a markedly decreased antioxidant capacity and enhanced eicosanoid production in RA. Univariate linear regression analysis showed a positive correlation (r = 0.383; p less than 0.005) between serum levels of vitamin A and zinc, and between serum retinol binding protein (RBP) and zinc (r = 0.440, p less than 0.02). These findings suggest that hypovitaminosis A in RA may be mediated by decreased vitamin A transport from the liver to the blood, caused by the low level of zinc dependent hepatic retinol binding protein synthesis. In multiple linear regression analysis, the serum zinc level emerged as the most significant variable and had an independent predictive value of 15.2% for vitamin A. Variations in the serum vitamin E levels were only explained by seropositivity (predictive value of 14.2%), a finding which suggests that the decreased level of vitamin E is a constant feature in RA rather than part of the acute phase response.

Adult↗

PubMed2005

Comparative longitudinal study of cervical length and induced shortening changes among singleton, twin, and triplet pregnancies.

OBJECTIVE: To compare cervical length and induced shortening changes during gestation among singleton, twin, and triplet pregnancies. STUDY DESIGN: Thirty-two healthy gravidas (12 singleton, 13 twin, and 7 triplet pregnancies) between 17 and 20 weeks' gestation were prospectively enrolled in this longitudinal investigation of cervical length. Serial transperineal cervical length ultrasound assessments were made weekly until 34 weeks' gestation under 3 conditions: 1) supine, 2) supine with the Valsalva maneuver, and 3) standing. Cervical length, internal os diameter, and presence of cervical funneling were assessed under each condition. Multiple regression models were created using generalized estimating equations to predict these measures and accounting for confounding effects from covariates and adjusting for correlations from repeated measurements on each woman. RESULTS: A total of 1286 cervical sonographic measurements were made. In a multiple linear regression generalized estimating equations model, estimated cervical length was significantly different among singleton, twin, and triplet pregnancies. Overall, changing maternal position from supine to standing resulted in a nonsignificant change (-0.1 +/- 0.4 mm) in cervical length (P = .85). In contrast, measurement of cervical length during the Valsalva maneuver resulted in a significant reduction in cervical length when compared with the cervical length measured in supine (-1.0 +/- 0.3 mm) (P = .0009) and standing positions (-0.9 +/- 0.4) (P = .009). The observed induced shortening changes were similar across gestation, irrespective of singleton, twin, or triplet gestation. CONCLUSION: Longitudinal cervical length changes differ significantly throughout gestation among singleton, twin, and triplet pregnancies. Cervical length measurements made in a standing position are comparable with those measured while supine, whereas cervical lengths measured during the Valsalva maneuver are significantly shorter than those made in either the supine or standing position.

Cervix Uteri↗

PubMed2006

Relationship between the adiponectin-leptin ratio and parameters of insulin resistance in subjects without hyperglycemia.

We previously reported that the adiponectin-leptin (A/L) ratio was more efficacious as a parameter of insulin resistance than adiponectin or leptin alone, and a more sensitive and reliable marker of insulin resistance than homeostasis model assessment (HOMA-R) as the fasting plasma glucose (FPG) level elevated in type 2 diabetes mellitus. In this study, we examined the usefulness of the A/L ratio as compared to HOMA-R for assessing insulin resistance in Japanese subjects without hyperglycemia. A total of 411 Japanese adults without hyperglycemia (205 men, aged 49 +/- 10 years; 206 women, aged 48 +/- 10 years) were enrolled. We investigated the correlation between fasting serum insulin level, FPG, leptin or adiponectin, and body mass index (BMI), fat mass (FM), triglycerides (TGs), high-density lipoprotein (HDL) cholesterol, or preheparin serum lipoprotein lipase (LPL) as parameters of insulin resistance. Next, we examined the relationships between parameters of insulin resistance and the A/L ratio or HOMA-R. By simple regression of the correlation between serum insulin level, FPG, leptin or adiponectin, and each parameter of insulin resistance, the best correlation coefficients were seen in leptin (men, r = 0.501; women, r = 0.667) as compared with BMI, in leptin (men, r = 0.658; women, r = 0.747) as compared with FM, in adiponectin (r = -0.285) in men and leptin (r = 0.299) in women as compared with TGs, in adiponectin (men, r = 0.405; women; r = 0.442) as compared with HDL cholesterol, and in adiponectin (men, r = 0.228; women, r = 0.452) as compared with LPL. By simple regression of the correlation between A/L ratio or HOMA-R and each parameter of insulin resistance, the highest correlation coefficients were seen with the A/L ratio except HDL cholesterol in men. Next, we carried out multiple linear regression to analyze the association between A/L ratio or HOMA-R and FM, TGs, HDL cholesterol, and LPL, excluding BMI, simultaneously. In men, the A/L ratio was significantly correlated with FM and TGs, and HOMA-R was significantly correlated with FM. This model explained 34% of the variance in the A/L ratio and 17% of the variance in HOMA-R. In women, the A/L ratio was significantly correlated with FM and LPL, and HOMA-R was significantly correlated with FM and LPL. This model explained 39% of the variance in A/L ratio and 14% of the variance in HOMA-R. In conclusion, the present study suggested that the A/L ratio might be more useful than HOMA-R to accurately assess insulin resistance in subjects without hyperglycemia.

Adiponectin↗

PubMed2001

Association between genetic polymorphisms and biomarkers in styrene-exposed workers.

A comprehensive approach to evaluate genotoxic effects induced by styrene exposure was employed in 44 hand-lamination workers in comparison with 18 unexposed controls. The acquired data on single-strand breaks in DNA (SSBs), frequency of chromosomal aberrations and HPRT mutant frequency in peripheral blood lymphocytes were compared to the results on genotyping of some of the xenobiotic-metabolising enzymes (CYP1A1, CYP2E1, epoxide hydrolase and GSTM1, GSTP1 and GSTT1). Multifactorial regression analysis indicated that SSB in DNA were significantly associated with styrene exposure and with heterozygosity in CYP2E1 (5'-flanking region and intron 6; r(2)=0.614). The frequency of chromosomal aberrations (CA), as analysed by linear multiple regression analysis, significantly correlated with years of employment (P=0.004) and with combinations of epoxide hydrolase (EPHX) genotypes (exon 3, Tyr/His and exon 4, His/Arg), where individuals with low and medium activity EPHX genotypes exhibited higher frequencies of CA than those with high activity genotypes (P=0.044, r(2)=0.563). Moderately higher HPRT mutant frequencies were detected in styrene-exposed individuals (20.2 +/- 25.8 x 10(-6)) as compared to controls (13.3 +/- 6.3 x 10(-6)), but this difference was not significant. ANOVA (in the whole set of data) revealed that mutant frequencies at the HPRT gene were significantly associated with years of employment (F=6.9, P=0.0001), styrene in blood (F=10.1, P=0.0001), and heterozygosity in CYP2E1 (intron 6; F=13.5, P=0.0008) and GSTP1 (exon 5; F=3.6, P=0.038). In conclusion, our present data suggest that analysed biomarkers of DNA damage may be modulated by polymorphic CYP2E1, EPHX and GSTP1. In our study, styrene-specific DNA and haemoglobin adducts are under investigation. Completing these data with the results of genotyping of metabolising enzymes may provide a useful tool for individual genotoxic risk assessment.

Adult↗