ABSTRACT
Background: Inflammatory cytokines have been known to be associated with Chronic Heart Failure [CHF]. Given the importance of cytokines in the context of the failing heart, the prevalence of Interleukin-2 [IL-2] and Interferon-gamma [IFN-Gamma] polymorphisms was studied in patients with CHF due to ischemic heart disease in a casecontrol study
Methods: Fifty-six Iranian patients with CHF were enrolled in this study as the case group and compared with 139 healthy subjects, using polymerase chain reaction with sequence-specific primers method, so as to determine the frequency of alleles, genotypes and haplotypes of IFN-Gamma [+874 A/T] and IL-2 [-330 G/T, +166 G/T] SNPs
Results: The GG genotype at IL-2 -330 in patients with CHF was significantly overrepresented in comparison with the control group [p=0.013]. Such a positive genotypic association was also observed for IL-2 +166/TT [p=0.022]. Meanwhile, the GT genotype frequency at IL-2 -330/GT in the patient group was significantly lower than the one in healthy controls [p=0.049]. No significant association was detected between the IFN-Gamma gene polymorphisms and individuals' susceptibility to CHF
Conclusion: Certain genotypes in IL-2 gene were overrepresented in patients with CHF, which could render individuals more vulnerable to this disease
ABSTRACT
Background: Proinflammatory cytokines have been known to be elevated in patients with Chronic Heart Failure [CHF]. Given the importance of proinflammatory cytokines in the context of the failing heart, the prevalence of Tumor Necrosis Factor-alpha [TNF-alpha], Interleukin [IL]-6 polymorphisms in patients with CHF was studied due to ischemic heart disease
Methods: Forty three patients with ischemic heart failure were enrolled in this study and compared with 140 healthy individuals. The allele and genotype frequency of four Single Nucleotide Polymorphisms [SNPs] within the IL-6 [-174, nt565] and TNF-alpha [-308, -238] genes were determined, using Polymerase Chain Reaction with Sequence-Specific Primers [PCR-SSP] assay
Results: The frequency of the TNF-alpha [-238] A/A genotype was significantly higher in patients comparing to controls [p=0.043], while TNF-alpha G/A genotype at the same position decreased significantly, in comparison with controls [p=0.018]. The most frequent haplotype for TNF-alpha was A/A in the patient group in comparison with controls [p=0.003]. There was no significant difference in allele and genotype frequencies of IL-6 at positions -174 and nt565, and TNF-alpha at position -308
Conclusion: Certain alleles, genotypes, and haplotypes in TNF-alpha, but not IL-6, gene were overrepresented in patients with ischemic heart failure, which may, in turn, predispose individuals to this disease
ABSTRACT
Background: The most common chromosomal abnormality due to non-obstructive azoospermia [NOA] is Klinefelter syndrome [KS] which occurs in 1-1.72 out of 500-1000 male infants. The probability of retrieving sperm as the outcome could be asymmetrically different between patients with and without KS, therefore logistic regression analysis is not a well-qualified test for this type of data. This study has been designed to evaluate skewed regression model analysis for data collected from microsurgical testicular sperm extraction [micro-TESE] among azoospermic patients with and without non-mosaic KS syndrome
Materials and Methods: This cohort study compared the micro-TESE outcome between 134 men with classic KS and 537 men with NOA and normal karyotype who were referred to Royan Institute between 2009 and 2011. In addition to our main outcome, which was sperm retrieval, we also used logistic and skewed regression analyses to compare the following demographic and hormonal factors: age, level of follicle stimulating hormone [FSH], luteinizing hormone [LH], and testosterone between the two groups
Results: A comparison of the micro-TESE between the KS and control groups showed a success rate of 28.4% [38/134] for the KS group and 22.2% [119/537] for the control group. In the KS group, a significantly difference [P<0.001] existed between testosterone levels for the successful sperm retrieval group [3.4 +/- 0.48 mg/mL] compared to the unsuccessful sperm retrieval group [2.33 +/- 0.23 mg/mL]. The index for quasi Akaike information criterion [QAIC] had a goodness of fit of 74 for the skewed model which was lower than logistic regression [QAIC=85]
Conclusion: According to the results, skewed regression is more efficient in estimating sperm retrieval success when the data from patients with KS are analyzed. This finding should be investigated by conducting additional studies with different data structures
ABSTRACT
Latent class analysis (LCA) is a method of assessing and correcting measurement error in surveys. The local independence assumption in LCA assumes that indicators are independent from each other condition on the latent variable. Violation of this assumption leads to unreliable results. We explored this issue by using LCA to estimate the prevalence of illicit drug use in the Iranian Mental Health Survey. The following three indicators were included in the LCA models: five or more instances of using any illicit drug in the past 12 months (indicator A), any use of any illicit drug in the past 12 months (indicator B), and the self-perceived need of treatment services or having received treatment for a substance use disorder in the past 12 months (indicator C). Gender was also used in all LCA models as a grouping variable. One LCA model using indicators A and B, as well as 10 different LCA models using indicators A, B, and C, were fitted to the data. The three models that had the best fit to the data included the following correlations between indicators: (AC and AB), (AC), and (AC, BC, and AB). The estimated prevalence of illicit drug use based on these three models was 28.9%, 6.2% and 42.2%, respectively. None of these models completely controlled for violation of the local independence assumption. In order to perform unbiased estimations using the LCA approach, the factors violating the local independence assumption (behaviorally correlated error, bivocality, and latent heterogeneity) should be completely taken into account in all models using well-known methods.
Subject(s)
Bias , Mental Health , Methods , Prevalence , Self Report , Substance-Related Disorders , Surveys and QuestionnairesABSTRACT
Dental caries is one of the most preventable yet prevalent chronic diseases worldwide. Our objective was to evaluate the effect of family structure and behavioral and eyesight problems as they relate to caries severity in schoolchildren. This research was carried out on 845 primary schoolchildren aged 9 yr in Kerman, Iran, in 2012. Ten variables, including health records, family structure information and a dmft / DMFT index, were collected. Children were categorized into three groups based on the WHO caries severity classification. Low caries level was defined as dmft/DMFT<2.6, moderate as dmft/DMFT of 2.7-4.4 and high as dmft/DMFT>4.4. The Cochran-Armitage test and ordinal logistic regression were employed for data analysis. Almost half of pupils had moderate or high caries severity. The odds of being in a higher caries severity category in pupils with behavioral problems [OR=2.37, 95% CI: 1.29-4.38] and girls [OR=1.6, 95% CI: 1.22-2.06] were higher than in other categories. In addition, pupils with eyesight problems [OR=0.58, 95% CI: 0.37-0.90] and overweight pupils [OR=0.46, 95% CI: 0.31-0.71] had lower caries severity than others. The effects of parents' education, birth rank, living with parents and consanguineous relationship between parents were not significant on caries severity [P>0.05]. Female pupils with behavioral problems were at a higher risk of caries severity than other pupils. These pupils need to be educated and coached on proper dental care. In addition, overweight pupils and those with eyesight problems had less caries severity than others. Family structure in this study did not have an effect on the severity of dental caries
Subject(s)
Humans , Male , Female , Family , Behavior , Logistic Models , Child , Schools , DMF IndexABSTRACT
The core concept of plagiarism is defined as the use of other people's ideas or words without proper acknowledgement. Herein, we used a questionnaire to assess the knowledge of students of Tehran University of Medical Sciences [TUMS] regarding plagiarism and copyright infringement. The questionnaire comprised 8 questions. The first six questions of the questionnaire were translations of exercises of a book about academic writing and were concerning plagiarism in preparing articles. Questions number 7 and 8 [which were concerning plagiarism in preparing Microsoft PowerPoint slideshows and copyright infringement, respectively] were developed by the authors of the present study. The validity of the questionnaire was approved by five experts in the field of epidemiology and biostatistics. A pilot study consisting of a test and retest was carried to assess the reliability of the questionnaire. The sampling method was stratified random sampling, and the questionnaire was handed out to 74 interns of TUMS during July and August 2011. 14.9% of the students correctly answered the first six questions. 44.6% of the students were adequately familiar with proper referencing in Microsoft PowerPoint slideshows. 16.2% of the students understood what constitutes copyright infringement. The number of correctly answered questions by the students was directly proportionate to the number of their published articles. Knowledge of students of TUMS regarding plagiarism and copyright infringement is quite poor. Courses with specific focus on plagiarism and copyright infringement might help in this regard
ABSTRACT
The purpose was to determine the familial aggregation of the total, against-the-rule [ATR], with-the-rule [WTR], and oblique astigmatism by conditional and marginal models in the Tehran Eye Study. Total, ATR, WTR, and oblique astigmatism were studied in 3806 participants older than 5 years from August 2002 to December 2002 in the Tehran Eye Study. Astigmatism was defined as a cylinder worse than or equal to -0.5 D. WTR astigmatism was defined as 0 +/- 19[degree sign], ATR astigmatism was defined as 90 +/- 19[degree sign], and oblique when the axes were 20-70[degree sign] and 110-160[degree sign]. The familial aggregation was investigated with a conditional model [quadratic exponential] and marginal model [alternating logistic regression] after controlling for confounders. Using the conditional model, the conditional familial aggregation odds ratios [OR] [95% confidence interval] for the total, WTR, ATRs, and oblique astigmatism were 1.49 [1.43-1.72], 1.91 [1.65-2.20], 2.00 [1.70-2.30], and 1.86 [1.37-2.54], respectively. In the marginal model, the marginal OR of the parent-offspring and sib-sib in the total astigmatism were 1.35 [1.13-1.63] and 1.54 [1.13-2.11], respectively; WTR 1.53 [1.06-2.20] and 1.94 [1.21-3.13] and; ATR 2.13 [1.01-4.50] and 2.23 [1.52-3.30]. The model was statistically significant in sib-sib relationship only for oblique astigmatism with OR of 3.00 [1.25-7.20]. The results indicate familial aggregation of astigmatism in the population in Tehran adjusted for age, gender, cataract, duration of education, and body mass index, so that the addition of a new family member affected with astigmatism, as well as having a sibling or parents with astigmatism, significantly increases the odds of exposure to the disease for all four phenotypes. This aggregation can be due to genetic and/or environmental factors. Dividing astigmatism into three phenotypes increased the odds ratios
ABSTRACT
To identify the effect of environmental factors on malaria risk, and to visualize spatial map of malaria standard incidence rates in Sistan and Baluchistan province, Islamic Republic of Iran. In this cross-sectional study, the data from 42,162 registered new malaria cases from 21 March 2001 [Iranian new year] to 21 of March 2006 were studied. To describe the statistical association between environmental factors and malaria risk, a generalized linear mixed model approach was utilized. In addition, we used the second ordered stationary Kriging, and a variogram to determine the appropriate spatial correlation structure among the malaria standard incidence rates, and provide a proper malaria risk map in the area under study. The obtained results from the spatial modeling revealed that humidity [p=0.0004], temperature [p < 0.0001], and elevation [p < 0.0001] were positively, and precipitation [p=0.0029] was inversely correlated with the malaria risk. Moreover, the malaria risk map based on the predicted values showed that the south part of this province [Baluchistan], has a higher risk of malaria, compared to the northern area [Sistan]. Since the effective environmental factors on malaria risk are out of human's control, the health policy makers in this province should pay more attention to the areas with high temperature, elevation, and humidity, as well as, low rainfall districts
Subject(s)
Humans , Male , Female , Incidence , Cross-Sectional StudiesABSTRACT
This study aimed to compare urinary Tamm-Horsfall protein [THP], citrate, and other inhibitors and promoters of stone formation in calcium stone formers with those in healthy individuals. From January 2002 to June 2004, 100 calcium stone formers [mean age, 38.6 +/- 10.3 years] who had at least 2 episodes of calcium stone formation were compared with 100 healthy individuals [mean age, 33.8 +/- 9.7 years]. Their 24-hour urine THP [using the sodium dodecyl sulfate polyacrylamide gel electrophoresis method], citrate, calcium, uric acid, oxalate, and magnesium values were measured and compared. The mean 24-hour urine THP was 3.3 +/- 8.1 mg in patients in the study group and 4.6 +/- 19.2 mg in controls [P=0.5]. However, THP in individuals with and without bacteriuria was significantly different [15.8 +/- 33.6 versus 2.6 +/- 10.2, P<0.001]. Mean 24-hour urinary calcium, citrate, and oxalate values were 232.6 +/- 95.3 mg and 177.8 +/- 82.7 mg [P<0.001], 132 +/- 103.2 mg and 395 +/- 258.5 mg [P<0.001], and 18.9 +/- 22.5 mg and 10.4 +/- 8.5 mg [P<0.001] in patients in the study and control groups, respectively. There was a significant positive correlation between urinary citrate and promoters of stone formation, including urinary calcium, oxalate, and uric acid, in patients in the control group, but not in patients in the study group. THP in the urine of stone formers is not quantitatively different from that of healthy individuals, but it is different in patients with bacteriuria. Increased urinary excretion of calcium, oxalate, and uric acid in stone formers with no increase in urine citrate may play a role in the pathogenesis of recurrent stone formation