Publications by authors named "Hojjat Zeraati"

106 Publications

Post-surgery Survival in Patients with Adenocarcinoma of Stomach Using Multistate Model.

J Gastrointest Cancer 2021 Feb 16. Epub 2021 Feb 16.

Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

Purpose: Stomach neoplasms are the fifth common cancer worldwide. The related factors for survival following stomach neoplasms are well-studied; however, information on recurrent events is limited. This study aimed to identify the related factors on recurrent and deaths following stomach neoplasms.

Methods: In this cohort study, information on 672 patients with adenocarcinoma who were hospitalized during 1995-2012 was used. Multistate models were applied to determine the effective factors on recurrent and death events.

Results: Median of survival time (months) and 5-year survival was estimated as 24.5 and 25%, respectively. The probability of death was 57% for non-recurrent patients, which increased to 88% among recurrent patients. Hazard of death was 49% lower for females (Hazard Ratio (HR):0.51, P = 0.009) while females had higher hazard of death following recurrent (HR:3.55, P < 0.001). Male patients and those with cardia involvement had higher risk of recurrence. A significant effect of age on the risk of death among patients with and without recurrence was estimated (HR:1.02, 1.03; P = 0.001 for both). Age, cardia involvement, and disease stage are amongst the effective factors on non-recurrent death while complement treatments increased the non-recurrent and recurrent survival.

Conclusion: In patients, effects of some factors for survival may vary throughout the course of disease and depend on recurrence status. We found that while female patients experienced lower recurrence, they had higher risk of death following recurrence. Age, tumor location, and type of therapy were risk factors for non-recurrent death. Finally, tumor location and type of surgery had significant effects on recurrence.
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http://dx.doi.org/10.1007/s12029-021-00599-wDOI Listing
February 2021

Bayesian methods for clinicians.

Med J Islam Repub Iran 2020 13;34:78. Epub 2020 Jul 13.

Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

The Bayesian methods have received more attention in medical research. It is considered as a natural paradigm for dealing with applied problems in the sciences and also an alternative to the traditional frequentist approach. However, its concept is somewhat difficult to grasp by nonexperts. This study aimed to explain the foundational ideas of the Bayesian methods through an intuitive example in medical science and to illustrate some simple examples of Bayesian data analysis and the interpretation of results delivered by Bayesian analyses. In this study, data sparsity, as a problem which could be solved by this approach, was presented through an applied example. Moreover, a common sense description of Bayesian inference was offered and some illuminating examples were provided for medical investigators and nonexperts. Data augmentation prior, MCMC, and Bayes factor were introduced. Data from the Khuzestan study, a 2-phase cohort study, were applied for illustration. Also, the effect of vitamin D intervention on pregnancy outcomes was studied. Unbiased estimate was obtained by the introduced methods. Bayesian and data augmentation as the advanced methods provide sufficient results and deal with most data problems such as sparsity.
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http://dx.doi.org/10.34171/mjiri.34.78DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7711039PMC
July 2020

Spatio-temporal analysis of misaligned burden of disease data using a geo-statistical approach.

Stat Med 2021 Feb 6;40(4):1021-1033. Epub 2020 Dec 6.

Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

Data used to estimate the burden of diseases (BOD) are usually sparse, noisy, and heterogeneous. These data are collected from surveys, registries, and systematic reviews that have different areal units, are conducted at different times, and are reported for different age groups. In this study, we developed a Bayesian geo-statistical model to combine aggregated sparse, noisy BOD data from different sources with misaligned areal units. Our model incorporates the correlation of space, time, and age to estimate health indicators for areas with no data or a small number of observations. The model also considers the heterogeneity of data sources and the measurement errors of input data in the final estimates and uncertainty intervals. We applied the model to combine data from nine different sources of body mass index in a national and sub-national BOD study. The cross-validation results confirmed a high out-of-sample predictive ability in sparse and noisy data. The proposed model can be used by other BOD studies especially at the sub-national level when the areal units are subject to misalignment.
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http://dx.doi.org/10.1002/sim.8817DOI Listing
February 2021

Accelerated and Standard Corneal Cross-Linking Protocols in Patients with Down Syndrome: A Non-inferiority Contralateral Randomized Trial.

Ophthalmol Ther 2020 Dec 1;9(4):1011-1021. Epub 2020 Oct 1.

Noor Ophthalmology Research Center, Noor Eye Hospital, Tehran, Iran.

Introduction: To compare the results of an accelerated corneal cross-linking (CXL) protocol (9 mW/cm, 10 min) with the standard CXL protocol (3 mW/cm, 30 min) in patients with Down syndrome (DS) who have keratoconus (KC).

Methods: Twenty-seven 10- to 20-year-old patients with DS who had bilateral progressive KC were enrolled in a contralateral randomized trial and completed 2 years of follow-up examinations. Fellow eyes were randomly allocated to the accelerated CXL group or the standard CXL group. The main outcome measure was change in maximum keratometry (K) centered on the steepest point (zonal K - 3 mm) with a non-inferiority margin of 1.0 diopter (D). Vision and refraction tests, ophthalmic examinations, and corneal tomography were performed at baseline and at 6, 12, and 24 months after CXL. Failure was defined as an increase of ≥ 1.0 D in zonal K - 3 mm within a 12-month period.

Results: The mean age (± standard deviation) of the patients was 15.71 ± 2.40 years. The within-group change in zonal K - 3 mm was not significant after 2 years in either group, and within-group zonal K - 3 mm remained stable. At 2 years after CXL, the mean change in the zonal K - 3 mm was - 0.02 ± 0.81 D and - 0.31 ± 0.86 D in the accelerated CXL and standard CXL groups, respectively (P = 0.088). At 1 year of follow-up, three patients in the accelerated CXL group showed treatment failure (mean change in zonal K - 3 mm + 2.12 ± 0.11 D); no patients in the standard CXL group showed treatment failure. At 2 years of follow-up, these three patients showed a decrease of - 0.43 ± 0.18 D in zonal K - 3 mm from a baseline value of 55.11 ± 0.32 D. The 2-year trends of the inferior-superior asymmetry and vertical coma were statistically significantly different between the two groups, with the accelerated CXL protocol showing superiority in patients with higher baseline values.

Conclusion: In young patients with Down syndrome, the accelerated CXL protocol was able to halt disease progression and may be an alternative for the standard CXL protocol. In advanced KC, the efficacy of the accelerated approach was delayed and appeared later in the follow-up. In asymmetric cornea, the accelerated CXL resulted in centralization of the corneal cone.

Trial Registration: Iranian Registry of Clinical Trials, IRCT20100706004333N3.
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http://dx.doi.org/10.1007/s40123-020-00303-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7708533PMC
December 2020

Comparing four laboratory three-parent techniques to construct human aged non-surrounded nucleolus germinal vesicle oocytes: A case-control study.

Int J Reprod Biomed 2020 Jun 30;18(6):425-438. Epub 2020 Jun 30.

Reproductive Biotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran.

Background: The three-parent assisted reproductive technique may increase oocyte competence.

Objective: In this case-control study, the suitability of germinal vesicle transfer (GVT), synchronous ooplasmic transfer (sOT), asynchronous ooplasmic transfer using cryopreserved MII oocyte (caOT), and asynchronous ooplasmic transfer using waste MII oocyte (waOT) for maturation of the human-aged non-surrounded nucleolus germinal vesicle-stage (NSN-GV) oocyte were investigated.

Materials And Methods: NSN-GV oocytes were subjected to four methods: group A (GVT), B (sOT), C (caOT) D (waOT), and E (Control). The fusion rates, MI, MII, ICSI observations and cleavage at 2-cell, 4-cell, and 8-cell stages were compared in the groups.

Results: In GVT, none of the oocytes fused. In sOT, all oocytes fused, 20 achieved the MI, 14 progressed to MII, 8 fertilized, 6 cleaved and 5, 4, and 3 achieved the 2-cells, 4-cells and 8-cells, respectively. In caOT, all oocytes fused and achieved the MI, 8 progressed to MII and fertilized, 6 cleaved and 6, 5, and 5 achieved the 2-cells, 4-cells, and 8-cells respectively. In waOT, all oocytes fused, 5 and 3 progressed to MI and MII, respectively, but only one fertilized, cleaved and reached a 4-cells stage. In group E, 6 and 2 oocytes progressed to MI and MII, respectively, and only one fertilized but arrested at the zygote stage. caOT had the highest survival rate when compared to sOT (p = 0.04), waOT (p = 0.002), and control (p = 0.001).

Conclusion: The caOT method was beneficial over sOT, waOT, and GVT in supplementing the developmental capacity of human-aged NSN-GV oocytes.
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http://dx.doi.org/10.18502/ijrm.v13i6.7284DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7340984PMC
June 2020

The Success Rate and Factors Affecting the Outcome of Assisted Reproductive Treatment in Subfertile Men.

Iran J Public Health 2020 Feb;49(2):332-340

Reproductive Biotechnology Research Center, Avicenna Research Institute, Tehran, Iran.

Background: This study was conducted to evaluate the success rate of male infertility treatment and the factors affecting its outcome.

Methods: In a historical cohort study, from Mar 2013 to Mar 2014, 323 couples with male factor were investigated. Couples had treated with IUI or/and ICSI were included randomly. Assisted reproduction technology (ART) outcome (treatment success) was defined as a live birth. Age, duration of infertility, type of infertility, treatment history and clinical examination results were investigated. The logistic regression and survival analysis were applied.

Results: The average of men age, duration of infertility and BMI were 33.5, 4.7 (yr) and 26.6 (kg/m) respectively. 87.9% of men have primary infertility and average duration of treatment was 14.1(month). Previous treatment, type of infertility, treatment method, man's BMI, normality of sperm and sperm head were important variable that affecting outcome. The rate of live birth in the first attempt was 29.7%, and 44.9% of the couples succeeded to give live birth after several treatment cycles. Couples who had no previous history of treatment were 8.5 times more successful in live birth. The Cox analysis showed that "BMI of man" and percentage of "Sperm with normal head" are predictors that had a significant effect on live birth.

Conclusion: Live birth in the first treatment cycles was influenced by four variables but two other variable were affecting several treatment cycles outcome. The chances of successful treatment were higher with taking into account the length of time and having live birth was determined as 78% for five years of continuous treatment.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7231713PMC
February 2020

Correction to: Health-related quality of life measured using the EQ-5D-5 L: population norms for the capital of Iran.

Health Qual Life Outcomes 2020 05 21;18(1):147. Epub 2020 May 21.

Department of Health Management and Economics, School of Public Health, Tehran University of Medical Sciences, Poursina Ave, Tehran, 1417613191, Iran.

An amendment to this paper has been published and can be accessed via the original article.
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http://dx.doi.org/10.1186/s12955-020-01397-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7243323PMC
May 2020

Post Liver Transplantation Survival and Related Prognostic Factors among Adult Recipients in Tehran Liver Transplant Center; 2002-2019.

Arch Iran Med 2020 05 1;23(5):326-334. Epub 2020 May 1.

Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

Background: Liver transplantation is a standard treatment for patients with end-stage liver disease (ESLD). However, with increasing demand for this treatment and limited resources, it is available only to patients who are more likely to survive. The primary aim was to determine prognostic factors for survival.

Methods: We collected data from 597 adult patients with ESLD, who received a single organ and initial orthotopic liver transplantation (OLT) in our center between 20 March 2008 and 20 March 2018. In this historical cohort study, univariate and multiple Cox model were used to determine prognostic factors of survival after transplantation.

Results: After a median follow-up of 825 (0-3889) days, 111 (19%) patients died. Survival rates were 88%, 85%, 82% and 79% at 90 days, 1 year, 3 years, and 5 years, respectively. Older patients (HR = 1.27; 95% CI: 1.01-1.59), presence of pre-OLT ascites (HR = 2.03; 95% CI: 1.16-3.57), pre-OLT hospitalization (HR = 1.88; 95% CI:1.02-3.46), longer operative time (HR = 1.006; 95% CI: 1.004-1.008), post-OLT dialysis (HR = 3.51; 95% CI: 2.07-5.94), cancer (HR = 2.69; 95% CI: 1.23-5.89) and AID (HR = 2.04; 95% CI: 1.17-3.56) as underlying disease versus hepatitis, and higher pre-OLT creatinine (HR = 1.67; 95% CI: 1.10-2.52) were associated with decreased survival.

Conclusion: In this center, not only are survival outcomes excellent, but also younger patients, cases with better pre-operative health conditions, and those without complications after OLT have superior survival.
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http://dx.doi.org/10.34172/aim.2020.22DOI Listing
May 2020

Health-related quality of life measured using the EQ-5D-5 L: population norms for the capital of Iran.

Health Qual Life Outcomes 2020 Apr 25;18(1):108. Epub 2020 Apr 25.

Department of Health Management and Economics, School of Public Health, Tehran University of Medical Sciences, Poursina Ave, Tehran, 1417613191, Iran.

Objectives: EQ-5D is the most commonly used generic preference-based health-related quality of life (HRQoL) measure. The current study aimed at estimating the HRQoL index scores using EQ-5D-5 L measure in the capital of Iran; moreover, identifying some determinants of the HRQoL.

Methods: A sample of 3060 subjects was selected by a stratified random sampling method from the general adult population of Tehran. Face-to-face interview was conducted to fill out the questionnaire, in this cross-sectional survey. EQ-5D-5 L utility score were estimated using an interim value set, based on a crosswalk methodology. Additionally, the relationships between HRQoL and sociodemographic characteristics were tested by generalized linear model, using STATA version 13.

Results: The mean ± standard deviation utility and EQ-VAS scores were 0.79 ± 0.17 and 71.72 ± 19.37. The utility scores ranged 0.61 ± 0.19 in > 69 year-old females to 0.88 ± 0.12 in < 30 year-old males. In mobility, self-care, and usual activity dimensions, most of the respondents reported "no problems" (70.47, 90.62, and 76.34%, respectively). However, in anxiety/depression and pain/discomfort dimensions, most of the respondents had problems (53.23 and 54.03%, respectively). Females had lower utility score than males; the utility score reduced with age increase; the educational level lead to higher utility scores; and the utility scores of individuals without spouse (divorced or widowed) were lower than those of the married individuals and never married ones.

Conclusions: The current study reported HRQoL norm data for the general adult population in the capital of Iran; these data could be very useful for policy making and economic evaluations. A significant percentage of people in Tehran reported anxiety/ depression, which highlights the risk of psychological problems. Effective interventions are needed to increase their HRQoL, especially for the vulnerable groups of the community.
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http://dx.doi.org/10.1186/s12955-020-01365-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7183694PMC
April 2020

Horizontal inequity in the utilization of cataract surgery in Iran: Shahroud Eye Cohort Study, 2009-2014.

Med J Islam Repub Iran 2019 30;33:116. Epub 2019 Oct 30.

Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

Since there was no evidence about economic inequity in utilization of cataract surgery in developing countries, such as Iran, this study was designed to measure horizontal inequity in the utilization of cataract surgery and its changes in an Iranian middleaged population in 2009 and 2014. Using data from the first and second phases of Shahroud Eye Cohort Study (2009-2014), the economic inequity in the utilization of cataract surgery in an Iranian middle-aged population aged 40-64 years in 2009 and 2014 was evaluated. The horizontal inequity index (HI) was determined using the indirect standardization method based on a nonlinear (probit) model and the concentration index (C) was decomposed into the contribution of each factor. The analyses were performed using STATA software version 12/SE, and significance level was set at less than 0.05. The HI in the utilization of cataract surgery increased from 0.080 (95% CI: 0.011-0.098) in 2009 to 0.166 (95% CI: 0.0821- 0.228) in 2014. Decomposition of changes in the concentration index showed that among need and non-need variables, older age and economic status (being among the wealthiest 20%) were the greatest contributors, with shares of 67.5% and 57.5%%, respectively, which led to pro-rich inequity during the study periods. The present study demonstrated that utilization of cataract surgery did not have an equal distribution among economic quintiles, despite considering equal needs based on cataract severity. Results demonstrated that older age and economic status were the greatest contributors to HI increase in 2009 and 2014.
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http://dx.doi.org/10.34171/mjiri.33.116DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6946921PMC
October 2019

Relationship between lifestyle pattern and blood pressure - Iranian national survey.

Sci Rep 2019 10 23;9(1):15194. Epub 2019 Oct 23.

Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

We aimed to evaluate the relationship between different lifestyle patterns and blood pressure. This study is based on the national survey of the risk factors for non-communicable diseases in Iran in 2012. A total of 8244 people aged 25-70 years old have been enrolled in the survey. Clustering on the individual data of lifestyle factors (nutrition, physical activity, and smoking) were carried out using self-organizing neural network method. Multivariable regression models were used to determine the relationship between blood pressure and the clusters. This study revealed seven lifestyle clusters in the national survey. The first cluster had a healthier lifestyle (15%), and the rest of the clusters had at least one or more lifestyle-related risk factors. Among all the clusters, people in two clusters, i.e. one characterized by consumption of sugar-sweetened beverages, salt, and fast foods, and the other one characterized by physical inactivity, were more exposed to the risk of hypertension (odds ratios of 1.44 and 1.12, respectively). People in another cluster who were 100% smokers and had a very high level of work-related physical activity were about 30% less likely to experience elevated blood pressure. Although a lifestyle with cigarette smoking was associated with a reduction in blood pressure, this might be due to other related factors, such as work-related physical activity, which lower blood pressure. Of course, this hypothesis still needs to be further studied in the future.
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http://dx.doi.org/10.1038/s41598-019-51309-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6811561PMC
October 2019

Investigation of Prognostic Factors of Survival in Breast Cancer Using a Frailty Model: A Multicenter Study.

Breast Cancer (Auckl) 2019 29;13:1178223419879112. Epub 2019 Sep 29.

Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

Background: Using data from different health centers can provide more accurate knowledge of the survival prognostic factors and their effect on the patient's survival. In this multicenter study, we aimed to investigate the role of prognostic factors on breast cancer survival with large data set.

Methods: This historical cohort study was carried out using data from 1785 participants with breast cancer. Data were gathered from medical records of patients referring to 4 breast cancer research centers in Tehran, Iran, between 1997 and 2013. Age at diagnosis (year), size of the tumor, involve lymph nodes, tumor grade, type of surgery, auxiliary treatment of chemotherapy, radiotherapy, recurrence, and metastasis were the prognosis factors considered in this study. A shared frailty model with a gamma distribution for frailty term was used.

Results: The median follow-up period was 29.71 months with the interquartile range of 19 to 61 months. During the follow-up period, 337 (18.9%) patients died from breast cancer and 1448 (81.1%) survived. The 1-, 3-, 5-, and 10-year survival rates were 96%, 84%, 76%, and 58%, respectively. In the Cox model by centers, in Center A, the type of surgery, number of nodes involved, and the grade 3 tumor; in center B, age, radiotherapy, metastasis, and between 1 and 3 involved nodes; in center C, age, radiotherapy, recurrence, metastasis, tumor size, and grade 3 tumor; and in center D, chemotherapy, metastasis, and lymph nodes involved were significant. Shared frailty model showed that type of surgery, number of lymph nodes involved, metastasis, radiotherapy, and the tumor grade are the prognostic factors survival in breast cancer. The frailty variance was significant, and it affirmed there was significant variability between centers.

Conclusions: This study showed it is necessary to consider the frailty term in modeling multicenter survival studies and confirmed the importance of early diagnosis of cancer before the involvement of lymph nodes and the onset of metastasis and timely treatment could lead to longer life and increased quality of life for patients.
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http://dx.doi.org/10.1177/1178223419879112DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6769229PMC
September 2019

Assessment of the immunogenicity and protective efficiency of a novel dual-promoter DNA vaccine, harboring SAG1 and GRA7 genes, from RH strain of in BALB/c mice.

Infect Drug Resist 2019 15;12:2519-2530. Epub 2019 Aug 15.

Department of Medical Parasitology and Mycology, Tehran University of Medical Sciences, Tehran, Iran.

Background: Toxoplasmosis, a protozoan parasitic disease caused by , has been a serious human and veterinary medicine problem with global distribution. In the current study, we assessed immunogenicity and protective efficiency of a novel dual-promoter DNA vaccine, harboring SAG1 and GRA7 genes, from RH strain of () with or without CpG-ODN as adjuvant in a murine model.

Methods: BALB/c mice were immunized intramuscularly with pVitro-SAG1-GRA7 alone and pVitro-SAG1-GRA7 with CpG-ODN three times at three-week intervals. Enzyme-linked immunosorbent assay (ELISA) was used to assess total IgG, IgG1 and IgG2a antibodies and gamma interferon (IFN-γ) and interleukin-10 (IL-10) cytokines in mice sera. Four weeks post final vaccination, MTT assay and lethal challenge-infection with 1×10 tachyzoites of RH strain were carried out to assess stimulation index (SI) and mice survival time, respectively.

Results: The IgG levels in mice immunized with multicomponent vaccines, including pVitro-SAG1-GRA7 alone and pVitro-SAG1-GRA7 with CpG-ODN, were significantly higher than those in control mice or single-gene DNA-vaccinated ones (<0.05). Furthermore, level of IgG2a in mice receiving pVitro-SAG1-GRA7 with CpG-ODN was significantly higher than that in mice receiving pVitro-SAG1-GRA7 alone (<0.05). The lysate antigen (TLA)-stimulated lymphocytes from pVitro-SAG1-GRA7 with CpG-ODN group responded more dramatically than those from control groups or single-gene DNA-vaccinated groups (<0.001). The pVitro-SAG1-GRA7 with CpG-ODN-vaccinated mice developed high levels of IgG2a and IFN-γ (<0.001) and low levels of IgG1 and IL-10, compared to control groups, suggesting a modulated immune response type Th1. In addition, survival time of the mice immunized with pVitro-SAG1-GRA7 with CpG-ODN was significantly extended, compared to controls (<0.05); however, all mice died.

Conclusion: The multivalent pVitro-SAG1-GRA7 DNA vaccine with CpG-ODN adjuvant is a promising vaccine candidate against toxoplasmosis.
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http://dx.doi.org/10.2147/IDR.S209270DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6699518PMC
August 2019

The reduction of horizontal inequity in unmet refractive error: The Shahroud Eye Cohort Study, 2009-2014.

J Curr Ophthalmol 2019 Jun 27;31(2):188-194. Epub 2018 Dec 27.

Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

Purpose: To measure Horizontal Inequity Index (HI) of unmet refractive error and its changes between 2009 and 2014 in Iran.

Methods: The data used in this study was taken from population-based study, Shahroud Eye Cohort Study. The number of participants analyzed in first (2009) and second phases of study (2014) were 5190 and 4737, respectively, and individuals between 40 and 64 years were included. The HI was determined by using the Concentration Index (C) based on the nonlinear (Probit) model, and C was decomposed to identify and quantify the contribution of each factor.

Results: After adjusting for need variables, the results demonstrated that the HI in unmet refractive need decreased from -0.288 (95% CI: 0.370, -0.206) in the 2009 to -0.132 (95% CI: 0.290, -0.028) in 2014. Decomposition of the C showed that level of education and economic status were the greatest contributors with shares of 26.2% and 17.9%, respectively, in reducing the amount of HI in unmet refractive error between 2009 and 2014.

Conclusions: The current study demonstrated that unmet refractive error did not have an equal distribution among economic quintiles, despite the same need for correcting refractive errors. Reducing the amount of HI in unmet refractive error between 2009 and 2014 indicated an improvement in the unmet need in the five years period between two phases of study.
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http://dx.doi.org/10.1016/j.joco.2018.12.001DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6611932PMC
June 2019

Casual effect of methotrexate+etanercept/infliximab on survival of patients with rheumatoid arthritis.

Pragmat Obs Res 2019 18;10:23-28. Epub 2019 Apr 18.

Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

Following the discovery of new drugs, physicians and pharmaceutical companies have become interested in examining patients' mortality and morbidity rates. In this respect, the effects of methotrexate (MTX)+etanercept/infliximab (ETA/INF) therapy on the survival of rheumatoid arthritis patients (RA) were evaluated in this study using marginal structural piecewise constant baseline hazard model. According to the standard protocol, MTX is considered as the first-line treatment for RA patients. If there is no adequate response to MTX, biologic drugs will be added. To compare the survival rates of RA patients in MTX- and MTX+ETA/INF-treated groups, the piecewise constant baseline hazard model was fitted. Then, due to the existence of the time-dependent confounder (VAS) which was affected by previous treatment, the weight for each person-time was calculated via the inverse probability treatment weighting method. These weights were then used by marginal structural piecewise constant baseline hazard model. Finally, these models were compared. The median (IQR) of the follow-up period in patients receiving MTX+ETN/INF and MTX was 11 (15.25) and 11 (31), respectively, and the 8-year survival rate was reported by 70% versus 68%, respectively. First, the piece-wise constant baseline hazard model was fitted. Fitting the given model showed that MTX+ETA/INF had a significant effect on patients' survival (HR=0.789, 95% CI [0.634, 0.983]). Second, marginal structural piecewise constant baseline hazard model was fitted. But, the results of this model revealed that MTX+ETA/INF did not have a significant impact on patients' survival (HR=0.968, 95% CI [0.860, 1.090]). Adjusting the pain score over time as a time-dependent confounder via marginal structural piecewise constant baseline hazard model, it has been demonstrated that MTX+ETA/INF does not have a significant effect on patients' survival rates. Therefore, a significant difference can be found between survival rates of these groups using longitudinal studies.
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http://dx.doi.org/10.2147/POR.S194408DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6503221PMC
April 2019

Asymptomatic malaria infections among immigrants in malaria-elimination programmed areas of south eastern Iran may threaten malaria eradication.

Travel Med Infect Dis 2019 Sep - Oct;31:101426. Epub 2019 May 18.

Center for Research of Endemic Parasites of Iran (CREPI), Tehran University of Medical Sciences, Tehran, Iran; Department of Medical Parasitology & Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran. Electronic address:

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http://dx.doi.org/10.1016/j.tmaid.2019.05.012DOI Listing
February 2020

Valuation of Quality Weights for EuroQol 5-Dimensional Health States With the Time Trade-Off Method in the Capital of Iran.

Value Health Reg Issues 2019 May 13;18:170-175. Epub 2019 May 13.

Department of Health Services Management, School of Public Health, Arak University of Medical Sciences, Arak, Iran.

Background: The EuroQol 5-dimension (EQ-5D) is a standard instrument that is widely used for measuring health-related quality of life and quality-adjusted life years in economic evaluation of healthcare interventions.

Objective: To estimate a preference valuation set for EQ-5D 3-level (3L) health states from the perspective of the general population in the capital of Iran.

Methods: Eight hundred seventy adults aged ≥18 years were interviewed in Tehran (Iran's capital) from July to November 2013. The participants were selected by a stratified random sampling method and were interviewed face-to-face at their usual residence. Forty-two health states were selected and valued from the 243 states derived from the EQ-5D-3L instrument. Each respondent valued 11 health states using the time trade-off method. Generalized least squares regression with random effect was used to predict values for health states.

Results: The analysis was performed for 846 respondents. The final model yielded the best fit for the time trade-off value at the individual level with an overall R of 0.45 and a mean absolute error of 0.214. The mean values for the 42 health states ranged from 0.934 for state 11121 to -0.142 for state 33333.

Conclusions: This study provided for the first time a value set for calculating quality-adjusted life years from the EQ-5D instrument in Iran. The Iranian EQ-5D-3L value set slightly differs from the value sets of the UK and the United States.
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http://dx.doi.org/10.1016/j.vhri.2019.01.007DOI Listing
May 2019

Evaluating the Potential of Three Sperm Surface Antigens as Egg-adhesion Biomarkers for Human Sperm Selection.

J Reprod Infertil 2018 Oct-Dec;19(4):203-210

Monoclonal Antibody Research Center, Avicenna Research Institute, ACERCR, Tehran, Iran.

Background: The selection of sperm with good genomic integrity and surface antigens is suggested for improving assisted reproductive technology (ART) outcome. The aim of this study was evaluating the heat shock protein (HSPA2), Dj-1 and serum amyloid P compound (SAP) three sperm surface proteomes as biomarkers for this purpose.

Methods: In this study, semen samples were obtained from 114 men who presented at Avicenna Fertility Clinic for their treatment. The semen characteristics, DNA fragmentation Index (DFI), chromatin maturation index (CMI), biomarker levels, and their embryo quality were considered. The paired-samples t-test and independent-samples t-test were used for analyzing the data and p-values<0.05 were considered significant.

Results: Outcomes exhibited the major reduction in HSPA2, DJ-1 and SAP following reduction in sperm quality and DNA integrity (p<0.001) with cut-off value of 14% (HSPA2), 12% (DJ-1) and 10% (SAP). The specificity of these three biomarkers was 95.2, 73.8 and 88.1%, respectively. Also, DFI (p<0.001), CMI (p<0.05), cleavage (p<0.05), and embryos quality (p<0.001) decreased significantly in abnormal spermiogram (ANS) group in compared with normal spermiogram (NS) group. It was shown that DFI was 97.1% in HSPA2, 76.5% in DJ-1 and 94.1% in SAP, and CMI was 95.0%, 75.50% and 87.5%, respectively. The significant correlation was found between of the three biomarkers and CMI (p<0.001), DFI (p<0.001) and embryos quality (p<0.001).

Conclusion: By comparing the efficiency of these three biomarkers for selecting sperm with the lowest level of chromatin damages, it seems that selection based on HSPA2 has significance over others.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6328979PMC
February 2019

Estimating the Net Survival of Patients with Gastric Cancer in Iran in a Relative Survival Framework.

Iran J Med Sci 2018 Nov;43(6):605-611

Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

Background: Iran is an Eastern Mediterranean region country with the highest rate of gastric cancer. The present study aimed to evaluate the 5-year net survival of patients with gastric cancer in Iran using a relative survival framework.

Methods: In a cross-sectional study, using life-table estimation of relative survival, we reported 1- to 5-year relative survival regarding age, sex, disease stage, pathology, and adjuvant therapies via modeling excess mortality. All the analyses were done applying Stata 11.2 with a confidence level of 95%.

Results: Data on 330 patients (aged 32-96 y), who were comprised of 228 (69.1%) men and 102 (30.1%) women with gastric cancer and were followed up for 10 years, were analyzed. Adenocarcinoma was the most common malignancy (281 [85.2%] patients), and 248 (75.1%) patients were at stage 3 or stage 4. The 1- and 5-year net survival rates after surgery were 67.96 (95% CI: 62.35-72.98) and 23.35 (95% CI: 17.94-29.28), respectively. Higher stages (P=0.001), older ages (P=0.007), and less use of adjuvant therapies (P<0.001) were independently associated with excess mortality.

Conclusion: It is recommended to use the relative survival framework to analyze the survival of cancer patients as an alternative approach not only to eliminate biases due to competing risks and their dependencies but also to estimate the cure at the population level concerning the most important individual characteristics. Our findings showed that the survival rate of gastric cancer in Iran is lower than that in most developed countries in terms of net survival.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6230936PMC
November 2018

Additional effect of etanercept or infliximab on the liver function tests of patients with rheumatoid arthritis: a cohort study.

Ther Clin Risk Manag 2018 9;14:1943-1950. Epub 2018 Oct 9.

Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran,

Purpose: One of the most important long-term side effects of therapy for rheumatoid arthritis (RA) is the elevation of liver function tests, with earlier studies reporting an elevation of more than 1× the upper limit of normal (>1 × ULN). The current study expands the literature by comparing the trends of transaminase changes caused by conventional and biologic disease-modifying antirheumatic drugs (DMARDs).

Patients And Methods: The drug categories examined were methotrexate (MTX) and all other nonbiologic DMARDs. Where RA patients exhibited inadequate response to conventional DMARDs (cDMARDs), we added biologic DMARDs (bDMARDs) to the treatment. We compared the trend of changes in alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in the patients receiving MTX with the trend observed in the patients whose treatment encompassed both bDMARDs and MTX. The comparison was conducted using random intercept models, which are a type of linear mixed effects model.

Results: This work involved 512 RA patients (MTX: 450, MTX + infliximab [INF]: 26, MTX + etanercept [ETA]: 36), whose ALT and/or AST levels were measured in 1,786 visits (MTX: 1,543, MTX + INF: 107, MTX + ETA: 136). ALT and/or AST elevations greater than 1 × ULN were observed in 344 (19.3%) visits (MTX: 295 [19.1%], MTX + INF/ETA: 49 [20.2%]). In this study, the trends of ALT and AST changes increased when receiving MTX, while the INF/ETA addition decreased these trends. The random intercept models indicated that changes in the mean ALT levels were significantly different over the time for MTX and MTX + INF/ETA groups (β [SE] =-0.190 [0.093], = 0.040) but changes in the mean AST levels were nonsignificantly different over the time for such groups (β [SE] =-0.099 [0.064], =0.120).

Conclusion: Despite a higher incidence of elevated transaminases during the use of MTX + INF/ETA, the combination of INF/ETA with MTX reduced transaminase levels and returned ALT levels to normal concentrations.
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http://dx.doi.org/10.2147/TCRM.S172836DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6186305PMC
October 2018

Lifestyle patterns in the Iranian population: Self- organizing map application.

Caspian J Intern Med 2018 ;9(3):268-275

Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

Background: The present study evaluated the lifestyle behavior patterns and its associations with demographic factors in the Iranian population.

Methods: A total of 8244 people aged 25-70 years who participated in a national survey in 2011 were included in the study. Factors related to lifestyle (such as diet, physical activity, and tobacco use) have been collected using a questionnaire. A self-organizing map was used for cluster analysis and a multinomial logistic model was used for assessment of associations.

Results: Seven clusters were identified as the following: cluster 1 (15.84%): healthiest lifestyle; cluster 2 (12.45%): excessive consumption of sweet tasting soft drinks, salt, and fast food; cluster 3 (33.73%): no recreational physical activity; cluster 4 (6.86%) alcohol consumption, smoking, and consumption of sweet tasting soft drinks; cluster 5 (14.18%): less salt and oil intake and lack of physical activity; cluster 6 (7.85%): no use of dairy products; cluster 7 (9.08%): the most unhealthy lifestyles; excessive work-related physical activity and smoking and unhealthy diet. Male gender was associated with higher odds of being in clusters 4 and 7. Individuals who were in unhealthy lifestyle clusters were mostly less educated and more self-employed or laborers.

Conclusions: A very small percentage of individuals was in the healthy lifestyle cluster yet they had poor nutrition. Health policy-makers should pay more attention to low recreational physical activity among elder people and in middle-aged and housekeepers, and also to high work-related physical activities that have a strong tendency to be in a cluster with smoking among workers and less educated men.
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http://dx.doi.org/10.22088/cjim.9.3.268DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6121339PMC
January 2018

Assessment of Horizontal Inequity in Eye Care Utilization in the Iranian Middle-aged Population.

J Ophthalmic Vis Res 2018 Jul-Sep;13(3):284-292

Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

Purpose: The present study was designed to determine the extent that horizontal inequity was realized regarding eye care utilization in a middle-aged population as well as factors affecting this equity.

Methods: Data were obtained from a population-based study (Shahroud Eye Cohort Study) in 2009 that included 5190 participants from 40 to 64 years of age. Horizontal inequity was determined based on the following variables: (i) economic status, (ii) eye care service needs, (iii) non-need variables, and (iv) eye care utilization (visiting an ophthalmologist or optometrist). Decomposition analysis of the concentration index based on a nonlinear model and indirect standardization was used to ascertain the contribution of each factor in inequity of eye care utilization.

Results: After adjusting for need variables, the results of our study demonstrated that horizontal inequity in eye care utilization in a middle-aged Iranian population remained positive and significant (horizontal inequity: 0.19; 95% confidence interval: 0.17-0.23) indicating that use of services was focused among participants with a better financial situation. Furthermore, decomposition analysis demonstrated that educational level and economic status had the greatest contribution (54.1% and 41.1%, respectively) in comparison to other variables.

Conclusion: This study demonstrated that horizontal inequity exists in eye care utilization among the middle-aged Iranian population.
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http://dx.doi.org/10.4103/jovr.jovr_221_17DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6058560PMC
August 2018

Healthy lifestyle behaviors and control of hypertension among adult hypertensive patients.

Sci Rep 2018 05 31;8(1):8508. Epub 2018 May 31.

Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

The aim of the present study was to evaluate the healthy lifestyle behaviors in hypertensive patients (aware, n = 1364 and not aware, n = 1213) based on 2011 national survey of risk factors of non-communicable disease (SuRFNCD) of Iran. Lifestyle score was calculated based on lifestyle behaviors, including smoking status, nutrition, physical activity status and body mass index separately for each patient. Of all aware patients, 27.79% (22.35-33.64) were adherence to the good lifestyle category. Almost the same percentage 29.24% (23.62-34.86) were observed in patients who were not aware of his/her illness. Moreover, adherence to good lifestyle is significantly higher in those who were aware without using antihypertensive medication (30.52% vs. 27.14%; p-value = 0.033). We also found that the prevalence of good lifestyle among patients with controlled hypertension is significantly higher than those who did not control his/her hypertension (32.54% vs. 27.59; p-value = 0.042). In people who were taking antihypertensive medication, adherence to healthy lifestyle did not have any significant relationship with the control of hypertension. The results of this study showed that awareness of hypertension did not improve people's lifestyle. However, those who aware, but not using any antihypertensive medications are able to control his/her level of blood pressure better than those using medications.
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http://dx.doi.org/10.1038/s41598-018-26823-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5981436PMC
May 2018

An agent based architecture for high-risk neonate management at neonatal intensive care unit.

Electron Physician 2018 Jan 25;10(1):6193-6200. Epub 2018 Jan 25.

Ph.D. Candidate of Health Information Management, Department of Medical Information Management, Faculty of Allied Sciences, Tehran University of Medical Science, Tehran, Iran.

Background: In recent years, the use of new tools and technologies has decreased the neonatal mortality rate. Despite the positive effect of using these technologies, the decisions are complex and uncertain in critical conditions when the neonate is preterm or has a low birth weight or malformations. There is a need to automate the high-risk neonate management process by creating real-time and more precise decision support tools.

Objective: To create a collaborative and real-time environment to manage neonates with critical conditions at the NICU (Neonatal Intensive Care Unit) and to overcome high-risk neonate management weaknesses by applying a multi agent based analysis and design methodology as a new solution for NICU management.

Methods: This study was a basic research for medical informatics method development that was carried out in 2017. The requirement analysis was done by reviewing articles on NICU Decision Support Systems. PubMed, Science Direct, and IEEE databases were searched. Only English articles published after 1990 were included; also, a needs assessment was done by reviewing the extracted features and current processes at the NICU environment where the research was conducted. We analyzed the requirements and identified the main system roles (agents) and interactions by a comparative study of existing NICU decision support systems. The Universal Multi Agent Platform (UMAP) was applied to implement a prototype of our multi agent based high-risk neonate management architecture.

Results: Local environment agents interacted inside a container and each container interacted with external resources, including other NICU systems and consultation centers. In the NICU container, the main identified agents were reception, monitoring, NICU registry, and outcome prediction, which interacted with human agents including nurses and physicians.

Conclusion: Managing patients at the NICU units requires online data collection, real-time collaboration, and management of many components. Multi agent systems are applied as a well-known solution for management, coordination, modeling, and control of NICU processes. We are currently working on an outcome prediction module using artificial intelligence techniques for neonatal mortality risk prediction. The full implementation of the proposed architecture and evaluation is considered the future work.
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http://dx.doi.org/10.19082/6193DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5853993PMC
January 2018

Economic Inequality in Presenting Vision in Shahroud, Iran: Two Decomposition Methods.

Int J Health Policy Manag 2018 01 1;7(1):59-69. Epub 2018 Jan 1.

Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

Background: Visual acuity, like many other health-related problems, does not have an equal distribution in terms of socio-economic factors. We conducted this study to estimate and decompose economic inequality in presenting visual acuity using two methods and to compare their results in a population aged 40-64 years in Shahroud, Iran.

Methods: The data of 5188 participants in the first phase of the Shahroud Cohort Eye Study, performed in 2009, were used for this study. Our outcome variable was presenting vision acuity (PVA) that was measured using LogMAR (logarithm of the minimum angle of resolution). The living standard variable used for estimation of inequality was the economic status and was constructed by principal component analysis on home assets. Inequality indices were concentration index and the gap between low and high economic groups. We decomposed these indices by the concentration index and BlinderOaxaca decomposition approaches respectively and compared the results.

Results: The concentration index of PVA was -0.245 (95% CI: -0.278, -0.212). The PVA gap between groups with a high and low economic status was 0.0705 and was in favor of the high economic group. Education, economic status, and age were the most important contributors of inequality in both concentration index and Blinder-Oaxaca decomposition. Percent contribution of these three factors in the concentration index and Blinder-Oaxaca decomposition was 41.1% vs. 43.4%, 25.4% vs. 19.1% and 15.2% vs. 16.2%, respectively. Other factors including gender, marital status, employment status and diabetes had minor contributions.

Conclusion: This study showed that individuals with poorer visual acuity were more concentrated among people with a lower economic status. The main contributors of this inequality were similar in concentration index and Blinder-Oaxaca decomposition. So, it can be concluded that setting appropriate interventions to promote the literacy and income level in people with low economic status, formulating policies to address economic problems in the elderly, and paying more attention to their vision problems can help to alleviate economic inequality in visual acuity.
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http://dx.doi.org/10.15171/ijhpm.2017.48DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5745868PMC
January 2018

Asymptomatic Malaria and its Challenges in the Malaria Elimination Program in Iran: a Systematic Review.

J Arthropod Borne Dis 2017 Jun 27;11(2):172-181. Epub 2017 May 27.

Center for Research of Endemic Parasites of Iran, Tehran University of Medical Sciences, Tehran, Iran.

Background: The objective of this study was to find an appropriate approach to asymptomatic malaria in elimination setting through a systematic review.

Methods: A broad search was conducted to find articles with the words 'malaria' in their titles and 'asymptomatic' or 'submicroscopic' in their texts, irrespective of the type of study conducted. The Cochrane, Medline/Pub Med, and Scopus databases, as well as Google Scholar were systematically searched for English articles and reports and Iran's databases-Iran Medex, SID and Magiran were searched for Persian reports and articles, with no time limitation. The study was qualitatively summarized if it contained precise information on the role of asymptomatic malaria in the elimination phase.

Results: Six articles were selected from the initial 2645 articles. The results all re-emphasize the significance of asymptomatic malaria in the elimination phase, and emphasize the significance of diagnostic tests of higher sensitivity to locate these patients and perform interventions to reduce the asymptomatic parasitic reservoirs particularly in regions of low transmission. However, we may infer from the results that the current evidence cannot yet specify an accurate strategy on the role of asymptomatic malaria in the elimination phase.

Conclusion: To eliminate malaria, alongside vector control, and treatment of symptomatic and asymptomatic patients, active and inactive methods of case detection need to be employed. The precise monitoring of asymptomatic individuals and submicroscopic cases of malaria through molecular assays and valid serological methods, especially in regions where seasonal and low transmission exists can be very helpful at this phase.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5641606PMC
June 2017

Variation of Housekeeping Genes in Clinical Isolates and Vaccine Strains of Bordetella pertussis.

Clin Lab 2017 Apr;63(4):809-815

Background: Bordetella pertussis causes serious contagious infections, primarily in childhood. A whole-cell vaccine, diphtheria-tetanus-whole cell pertussis (DTwP), has been used to protect against pertussis in children in Iran, but the pertussis cases have been increasing during recent years. We determined the allelic variation level of housekeeping genes in isolates recovered from pertussis patients and vaccine strains used in national vaccination program.

Methods: Five clinical isolates, 2 vaccine strains and a Tohama I strain were studied through multilocus sequence typing (MLST) of housekeeping genes. The relatedness between STs, the founder, single- and double-locus variants (SLVs, DLVs) was determined using eBURST algorithm. The concordance between the type assignments by MLST and PFGE was determined.

Results: In the 5 clinical isolates, 2 STs were identified, ST2 and ST79. The vaccine strains displayed two distinct allelic profiles assigned to ST1 and ST2. ST2 was predicted as founder and the remaining STs were SLVs of ST2. MLST and PFGE type assignments were 86.6% concordant.

Conclusions: The clinical isolates of B. pertussis were different from vaccine strains used in the national vaccination program. This study confirms the low level of variation in housekeeping genes of B. pertussis. MLST of virulent antigenic genes needs to be applied as a complementary method for the characterization of new ST-harboring isolates that may predominate periodically. The combination of these data allows rapid and efficient surveillance of currently circulating isolates. These data might elucidate the future trends and considerations for vaccine formulation and design.
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http://dx.doi.org/10.7754/Clin.Lab.2016.160920DOI Listing
April 2017

Detection of Clostridium difficile in Fecal Specimens: a Comparative Evaluation of Nucleic Acid Amplification Test and Toxigenic Culture.

Clin Lab 2016 Oct;62(10):1887-1892

Background: The available data regarding Clostridium difficile infections (CDIs) in developing countries are scarce. This may be related in part to the complexity of anaerobic bacterial culture and/or cytotoxicity assays of C. difficile. Here, we evaluated the diagnostic efficacy of PCR in comparison with toxigenic culture for direct detection of conserved genes as well as toxin genes of C. difficile in fecal specimens of patients with clinical symptoms of CDI.

Methods: Loose or soft feces from 171 patients suspected of having C. difficile associated diarrhea (CDAD) were subjected to DNA extraction, PCR of cdu-2, cdd-3, gdh, tpi, tcdA/B, and toxigenic culture (TC). Limit of detection (LoD) was defined as the lowest concentration of DNA at which the target gene was amplified via PCR. The Kappa agreement between two diagnostic tests was calculated.

Results: The in-house extraction method extracted DNA successfully as confirmed by amplification of conserved genes of C. difficile. LoD of PCR for total DNA was 0.064 ng/μL. Only 10 specimens were positive for C. difficile via both PCR and TC. Among 10 identified C. difficile strains, 8 were tcdA+B+, but 2 were tcdA-B+. A very good agreement was observed between TC as reference method and PCR (κ = 1).

Conclusions: Despite the high concordance between PCR and TC, this in-house nucleic acid amplification test can be used to identify symptomatic patients who harbor high amounts of bacteria. This procedure allows primary and same day diagnosis of C. difficile, and clinical laboratories in low-income countries may adopt the method for sample extraction and PCR assay at least for symptomatic patients.
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http://dx.doi.org/10.7754/Clin.Lab.2016.160112DOI Listing
October 2016

Simplified Pan-species Real-time PCR-based Detection of Spp. in Blood Smear.

Iran J Parasitol 2016 Oct-Dec;11(4):463-470

Center for Research of Endemic Parasites of Iran, Tehran University of Medical Sciences, Tehran, Iran; Department of Medical Parasitology & Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

Background: We aimed to quicken and simplify the detection of in blood samples by developing and testing a pan- real-time PCR for accurate screening of individuals suspected of malaria.

Methods: A single primer/probe set for pan-species -specific real time PCR targeting a conserved region of the small subunit 18S ribosomal DNA was designed and evaluated for rapid diagnosis and screening of malaria infections using dried blood smears. FTA cards were used for rapid and simple DNA extraction.

Results: The primers and probes showed a positive response with the DNA extracted from bloods infected with and but not with DNA extracted from various smears from uninfected blood samples. Seven positive cases positive by both microscopy and nested PCR were found among 280 blood samples taken from in South and Southeast Iran. Five samples were identified as positive for and two as positive for . All positive samples were positive by real-time PCR. Furthermore, all 38-blood samples positive by microscopy were positive by real-time PCR. No microscopy-negative samples were positive by real-time PCR.

Conclusion: By using a simple FTA card for DNA extraction and by application of the real-time PCR developed in this study, sensitivity similar to nested-PCR and microscopy was achieved. This format simplifies the detection of in large numbers of samples.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5251174PMC
January 2017

Bed Capacity Planning Using Stochastic Simulation Approach in Cardiac-surgery Department of Teaching Hospitals, Tehran, Iran.

Iran J Public Health 2016 Sep;45(9):1208-1216

Dept. of Cardiac Surgery, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.

Background: To determine the hospital required beds using stochastic simulation approach in cardiac surgery departments.

Methods: This study was performed from Mar 2011 to Jul 2012 in three phases: First, collection data from 649 patients in cardiac surgery departments of two large teaching hospitals (in Tehran, Iran). Second, statistical analysis and formulate a multivariate linier regression model to determine factors that affect patient's length of stay. Third, develop a stochastic simulation system (from admission to discharge) based on key parameters to estimate required bed capacity.

Results: Current cardiac surgery department with 33 beds can only admit patients in 90.7% of days. (4535 d) and will be required to over the 33 beds only in 9.3% of days (efficient cut off point). According to simulation method, studied cardiac surgery department will requires 41-52 beds for admission of all patients in the 12 next years. Finally, one-day reduction of length of stay lead to decrease need for two hospital beds annually.

Conclusion: Variation of length of stay and its affecting factors can affect required beds. Statistic and stochastic simulation model are applied and useful methods to estimate and manage hospital beds based on key hospital parameters.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5149475PMC
September 2016