[Related factors with obesity in Tehranian households: a cross-sectional study]

In 21[st] century obesity has rapidly increased and it has become one of the greatest public health problems worldwide. The aim of this study was to determine related factors with obesity in Tehranian households. In this descriptive study, multivariate analysis was used to estimate the odds of obesity [BMI >/= 30 kg/m2] as a function of age, sex, marital status, educational level and smoking by using data from" Tehran Lipid and Glucose Study [TLGS]" database. In this study 3,935 households participants who were equal or more than 20 years old, were recruited from phase III [2006-2008] of this study. Height of participants was measured to the nearest 5 mm without considering their shoe heels. Weight and height were measured using digital electric scale and meter tape. Data were analyzed by SPSS/16 and SAS version 9.1. The mean BMI was 26.59 [kg/m[2]] in men and 27.96 [kg/m[2]] in women. After adjustment for other variables, obesity odds ratios were 1.01 [P<0.001], 2.10 [P<0.001], and 1.54 [P<0.001] for age, women and married individuals, respectively. There was an inverse significant association between education and obesity. Obesity ORS were 0.83 [P<0.028] for high school and 0.50 [P<0.001] for university educational levels. The results of this study show that related factors in this research are similar to other countries. Therefore, obesity with related factors should be considered in health programming

Application of FBAT-MM and fbat-lc multimarker methods in association of selected microsatellites with hdl-c in families with metabolic syndrome members: tehran lipid and glucose study

Studying several linked markers provides more information on locating disease genes locus by using genetic association analysis. The aims of this study were to introduce Multimarker Family Base Association Tests [FBAT-MM] and its Linear Combination [FBAT-LC] in multimarker genetic association analysis and to examine the association of selected microsatellites with HDL-C in an Iranian population. One hundred twenty five [1 25] families having at least one member with metabolic syndrome and at least two members with low HDL-C were selected from participants of the Tehran Lipid and Glucose Study [TLGS]. Multimarker genetic association of HDL-C level with some microsatellites in the chromosomes 8, 11, 12, and 1 6 were examined using FBAT-MM and FBAT-LC methods. The families consisted of 563 individuals [269 males and 294 females]. FBAT-MM showed significant genetic association only between HDL-C and three microsatellites in Chromosome 1 1 [P<0.05]. The microsatellite Dl 1 SI 304 was found as the significant factor for multimarker genetic association. FBAT-MM and FBAT-LC did not show shortcomings such as excessive conservatism and low power which are, usually, observed in other multimarker methods. Finding microsatellites associated with HDL-C level can provide background for further researches on the role of predisposing genes in metabolic syndrome

G360t polymorphism in the APO AIV gene and its association with combined HDL/LDL-cholesterol phenotype: Tehran lipid and glucose study

Identifying genetic polymorphisms as risk factors for complex diseases can facilitate their prevention, diagnosis, and prognosis. The purpose of this study is to assess the association between Apo AIV polymorphism and lipid factors based on high density lipoprotein cholesterol [HDL-C] levels in a population of the Tehran Lipid and Glucose Study [TLGS]. A total of 181 elderly TLGS subjects with Combined HDLC/low density lipoprotein-Cholesterol [LDL-C] phenotype were investigated. The distributions of a polymorphic site in the apolipoprotein gene APO AIV and its relationship with total cholesterol, LDL-C, HDL-C, and triglycerides were investigated in subjects with LDL-C> 121 mg/dL and HDL-C< 40 mg/dL [case group] and those with LDL-C< 90 mg/dL and HDL-C> 50 [controls]. All the variables studied in the case and control groups were statistically different. At the APO AIV locus the G360T polymorphism at codon 360 showed a significant impact on total cholesterol [G: 211 +/- 1.16 vs, T: 228 +/- 1.20 mg/dL p 0.038] concentration in the case group and on Apo CIII [G: 157 +/- 66.9 vs, T: 83.18 +/- 17.1 mg/dL p <0001] level in the controls. These associations remained after adjustment for age, sex and smoking [P values: P Chol: 0.028 and P Apo CIII: 0.021]. Difference in the apolipoprotein AIV [G360T] polymorphism in the two groups with the combined HDL/LDL-C phenotype indicates that this phenotype can be a selective phenotype for genetic analysis in this field

[Genetic linkage analysis of HDL-C in 91 Iranian families with metabolic syndrome with Haseman-Elston regression methods]

Metabolic syndrome [Mets] is a common phenotype, which is affected on 32% of Iranian population. It is associated with an increased risk for cardiovascular disease. Low HDL-C is the most frequent phenotype in this disease. In this study in order to find some chromosomal region in related to the HDL-C in families with metabolic syndrome, twelve microsatellite markers were investigated in 91 families and done the Haseman-Elston Regression methods [oHE, sHE, rHE, W2, W3, tHE]. Finally, the results of these methods are compared. For analysis of the data, these softwares were used: power. HE [inR], Excel, PowerMarker, SPSS, S.A.G.E. In results of 4 methods, from these 7 methods, genetic linkage of HDL-C is significant with D11S1998 marker [p<0.05]. Other studies also show this result. These results can help me in future studies in Iranian population. Results show in which theoretical power of these methods is better, the empirical significance become less and this is an evidence for accepting significant linkage between D11S1998 marker and location of HDL-C gene

Microwave digestion for urine iodine determination

Digestion is an important step in urine iodine determination methods. High temperatures and long heating durations can be considered as weaknesses of the present methods. The aim of the study was assessment of microwave use for digestion of urine and decompostion of interfering substances, aimed at shortening the time and increasing safety in the procedure. Random urine samples were processed by conventional acid digestion and also by new microwave optimized digestion methods. After digestion, iodine levels of samples, digested by the two mentioned methods, were also determined using chemical colorimetric kinetic reaction Ce+4 and Ce+3 according to the well known Sandell-Kolthoff reaction. Microplate reading format by ELISA reader was used to increase speed and precision of reading. Sensitivity, precision and comparison results were assayed in both the methods as well. Optimized microwave digestion showed that merely a 10 min duration is adequate for complete digestion of urine samples. Intra- and inter- assay coefficients of variation were 6.7- 9.3% and 9.8-12.3% respectively. The final results of the comparison of iodine contents of samples, were obtained through the two microwave and conventional methods, showed acceptable correlation [r=0.928]. The assay recovery was 91-113% and the sensitivity 5 micro g/dL. The results of this study showed that the microwave procedure for urine digestion is acceptable. The digestion method obtained comparable results with conventional digestion methods, and can hence replace conventional electrical heat digestion methods

[Comparison of precipitation and direct methods for HDL-C assay]

HDL-C measurement is important in cardiovascular diseases evaluation. Precipitation method is common procedure in this measurement, but direct method widely used nowadays. The aim of the present study was to compare the results of the two aforementioned techniques and their correlation. During August 2006, serum HDL-C of 212 subjects [98 male, 114 female with the mean age of 39 +/- 20 year] referring for Tehran Lipid and Glucose Study were determined by direct and precipitation methods simultaneously. The HDL-C levels of the direct and precipitation methods were 43.5 +/- 10.2 and 45.2 +/- 10.9 mg/dl, respectively. Direct method had 3.9% higher value results [P=0.000] and two methods had good correlation [r=0.943]. Intraassay coefficient variation [CV] of precipitation and direct method were 5.6% and 3.3%, respectively. Assay time of direct method was half of precipitation method and its cost was 3 folds higher. The study revealed that the results of direct HDL-C method had good correlation with the precipitation method, its precision and speed was more acceptable. After moderating the price of direct method, it will be a good substitution for precipitating method

Acid digestion and microplate reading method for milk iodine determination

Main shortcomings in existing methods for iodine determination in milk samples are non safe alkaline solution, harsh thermal conditions, and their being time consuming. In this study, for determination of total iodine content in milk, a simple and rapid kinetic catalytic colorimetric, acid digestion and rapid microplate reading format method, was investigated. Sample digestion was done on 50 micro L milk in metavanadate/perchloric acid, at 230°C for 10 min. After digestion, iodine determination was based on famous Sandell - Kolthoff reaction. The reaction results were read in 96 wells microplate by ELISA reader. Work range of the assay was between 2-40 micro g/dl. The within-run coefficient of variation percent ranged from 6. 7 to 9. 3 and between-run coefficients of variation ranged from 8.6 to 12.3%. The results obtained [n = 70] by the optimized method had good correlation with the results of alkaline incineration as the reference method [p < 0.000, n = 70 r2 = 0.907 y = 0. 952x-0.084]. Recovery tests for accuracy assessment were between 91.3 to 113%. This method enabled us to achieve 0.1 micro g/dl sensitivity. This study showed that, fast acid digestion, mild thermal, fast results reading and low sample volume, were the main advantages of the acid digestion and microplate reading format investigated

[Association of apolipoprotein E gene polymorphism and obesity in an Iranian population: Tehran Lipid and Glucose study]

The Apo E is one of the genes, which play a role in the regulation of lipid metabolism, especially in obesity. In other studies a common Apo E polymorphism has been shown to be associated with obesity, and in the present study our aim is to determine this association in an Iranian population. Subjects were randomly selected from the Tehran Lipid and Glucose Study and classified into 3 in three groups according to their body mass index: BMI<25, 25.BMI<30, BMI.30 and finally 429[150 in men and 179 in women]. We measured FBS, HDL-C, triglyceride, cholesterol levels and blood pressure for all individuals. A segment of the mentioned gene with PCR was amplified and the polymorphism with RFLP [HhaI] revealed. The allele frequency of Apo E polymorphism was in the Hardy Weinberg equilibrium and the allele frequency was e2 [0.065], e3 [0.851] and e4 [0.083]; there was no relation between BMI and the frequency of this allele. These results show that there is no relation between Apo E polymorphism and BMI in this study

[Evaluation of HDL-C determination methods]

Following confirmation of the role of HDL-C role in cardiovascular disease, its measurement has become a fixed requirement by physicians. Today serum HDL-C is measured using different methods from simple outdated precipitation methods to the latest of homogenous assays used for HDL-C determination. However, the precision, accuracy and performance, standardization, and evaluation for those methods are controversial. This paper briefly discusses the methodology of various HDL-C determination methods e.g ultra centrifugation, electrophoresis, precipitation and homogenous assays, and advantages of homogenous methods. Human expertise, time consuming and high cost instrumentation of ultra centrifugation, quantitative electrophoresis, nuclear magnetic resonance and chromatographic methods are key factors that make the methods undesirable for clinical laboratories. Precipitation and manual separation steps of non homogenous HDL-C determination methods, reduces their precision, and causes them to be replaced by more precise methods such as homogenous assays; however more time is needed for their costs to be more competitive

[ multivariate study of metabolic syndrome risk factors, using factor analysis: Tehran lipid and glucose study]

Because of the high prevalence of the metabolic syndrome in Iran, this study used factor analysis to examine how the major components of the metabolic syndrome relate to each other and the role of hyperlipidemia in Iranian subjects. 8990 subjects aged over 18 years, participants of the Tehran Lipid and Glucose Study, were selected. Anthropometry, blood pressure, serum glucose and lipid concentrations were measured to estimate the prevalence of the metabolic syndrome. Before and after excluding individuals with diabetes and hypertension, we used factor analysis to examine the pattern of the metabolic syndrome in 3956 men and 5034 women. 26.6% of men and 36.3% of women had metabolic syndrome by ATPIII criteria and low HDL-C was the most frequent finding in subjects. Factor analysis reduced 8 anthropometric and metabolic variables into four uncorrelated factors. Four factors, which together account for 83.3% of the variance, can be identified: the first was obesity, blood pressure and hyperglycemia were second [hypertension] and the third factor was hypoglycemia. Dyslipidemia was the last factor and had a correlation with obesity. Findings support a concept in which the metabolic syndrome represents several distinct entities [dyslipidemia, obesity, hypertension and hyperglycemia] and obesity is the most important factor, having a strong correlation with dislipidemia in the Iranian population