159 research outputs found

    A qualitative survey of top-achieving undergraduate medical students’ perspectives of medical education: An Iranian exploration

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    Background. Curriculum reform has received a great deal of attention in the field of medical education in recent years. Many studies are being conducted worldwide to assess the deficiencies of current curricula in order to construct new ones.Objective. To investigate the perception of a group of students regarding the curriculum currently being taught in medical schools in Iran.Methods. This qualitative research was conducted in a cohort of 20 top-achieving students who ranked 1 - 10 in the medical university entrance examination and those who succeeded in the International Biology Olympiad examination in the past eight years. These students were in different stages of their studies, ranging from the second term of study to clerkship to internship. Several semi-structured focus group discussions were held and the results were extrapolated from the transcription of these sessions.Results. The majority of medical students, regardless of the stage of study, were deeply concerned about the current curriculum. They believed that the existing discipline-based approach, teacher-centred curriculum and shortage of hospital-based learning were deficient and suggested that the lectures, handouts, and multiple choice question examinations should be blamed for the development of unskilled doctors.Conclusion. There is a need for educational reform to contribute towards providing communities with doctors with better skills

    Estimating the avoidable burden of certain modifiable risk factors in osteoporotic hip fracture using Generalized Impact Fraction (GIF) model in Iran

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    Backgrounds: The number of hip fractures, the most common complication of osteoporosis, has increased rapidly over the past decades. The goal of this study is to estimate the avoidable burden of certain modifiable risk factor of the condition using the Generalized Impact Fraction (GIF) model, which has been suggested and used by epidemiologists to overcome the drawbacks associated with the use of Attributable Fraction index. In addition to preventing a risk factor or the avoidable fraction of burden, this index can also calculate the change in the burden, when a risk factor is altered.Methods: International databases were searched through PubMed, CINAHLD, Embase using OVID and Google scholar. National resources were searched through IranDoc, IranMedex, SID and Journal sites. Other resources include abstract books and articles sent to the IOF congress. The following search strategy was used: (" Osteoporotic fracture" OR " Fragility Hip fracture" OR " Calcium" OR " vitamin D" OR " BMI" OR " lean body weight" OR " Physical activity" OR " exercise" OR " Smoke" ) AND (" prevalence" OR " incidence" OR " relative risk" ) and limited to " humans." Results: With regards to different scenarios already explained in modifying the studied risk factors, the greatest impact in reducing the prevalence of risk factors on osteoporotic hip fractures, was seen in low serum vitamin D levels, low physical activity and low intake of calcium and vitamin D, respectively. According to the fact that interventions for low serum vitamin D and low intake of calcium and vitamin D, are related to each other, it can be concluded that implementing interventions to change these two risk factors, in the easy, moderate and difficult scenarios, would result in approximately a 5%, 11% and 17% decrease in the burden of osteoporotic hip fractures, respectively. The addition of interventions addressing low physical activity in the easy, moderate and difficult scenarios, an 8%, 21% and 35% reduction in the burden of osteoporotic hip fractures would be reported, respectively.Conclusion: Improving serum vitamin D levels, recommending the consumption of calcium and vitamin D supplementations and advocating physical activity are the most effective interventions to reduce the risk of osteoporotic hip fractures. © 2013 Shahnazari et al; licensee BioMed Central Ltd

    No evidence of association between CTLA-4 polymorphisms and systemic lupus erythematosus in Iranian patients

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    Aim: Cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) is an important negative regulator of T-cell responses. CTLA-4 polymorphisms have been confirmed to be associated with several autoimmune diseases such as systemic lupus erythematosus (SLE). We analyzed the role of CTLA-4 polymorphism at positions -1661 and -1722 in Iranian patients suffering from SLE. Methods: One hundred and eighty SLE patients and 304 ethnically and age-matched healthy controls were studied. Polymerase chain reaction restriction fragments length polymorphism (PCR-RFLP) was used to analyze the genotype and allele frequencies of these polymorphisms. Results: There was no significant association between the studied genotypic and allelic frequencies between SLE patients and the controls. Although the TC genotype in 1722TC polymorphism was more common among the control group, the correlation was not statistically significant. Conclusion: Our results suggest that the -1661AG and -1722TC polymorphisms in the promoter region of the CTLA-4 gene does not play any role in genetic susceptibility to SLE. However, further studies on larger sample sizes are needed to approve our results. © 2013 Asia Pacific League of Associations for Rheumatology and Wiley Publishing Asia Pty Ltd

    Association between CTLA-4 gene polymorphism and the risk of systemic lupus erythematosus: Brief report

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    Background: Cytotoxic lymphocyte antigen-4 (CTLA-4) plays an important role in regulating T cell activation. CTLA-4 gene polymorphisms are related with genetic susceptibility to various autoimmune diseases, including systemic lupus erythematosus (SLE). We analyzed the role of CTLA-4 polymorphisms at positions -318CT in patients who suffer from SLE. Methods: This study was performed on 180 SLE patients referred to 5th Azar University Hospital in Gorgan, Iran. Three hundred and four ethnically-and age-matched healthy controls with no history of autoimmune diseases entered the study between 5th May 2008 and 23rd October 2009. DNA was extracted from blood samples according to the standard procedure. Polymerase chain reaction- restriction fragments length polymorphism (PCR-RFLP) was used to analyze the genotype and allele frequencies of this polymorphism. PCR was carried out using the following primers: forward 5′- AAATGAATTGGACTGGATGGT-3′ and reverse 5′-TTACGAGAAAGGAAGCCGT G-3′. The frequency of alleles and genotypes were assessed using direct counting. Chisquare test and Fisher’s exact test were used to compare the association between the alleles and genotype frequencies and SLE. P<0.05 were considered statistically significant. Results: The CC genotype was observed in 94.5% of the SLE patients and 82.4% of the controls; the difference was statistically significant (P=0.0001, OR=3.51, CI95%=1.77- 7.53). The CT genotype, on the other hand, was more frequently observed in the control group (17.1% vs. 5.5%, P=0.0001, OR=0.28). T allele was significantly more common in the controls compared to SLE patients (P=0.0001, OR=0.26, CI95%=0.13-0.53). Conclusion: Our results suggest that the -318C/T polymorphism of CTLA-4 gene might play a significant role in the genetic susceptibility to SLE. Therefore, further studies on populations, especially from other Middle East countries, are needed to confirm our results. © 2015, Tehran University of Medical Sciences. All Rights Reserved

    A suggested prototype for assessing bone health

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    Background- Osteoporosis is becoming a health concern worldwide. Considering the fact that prevention plays an important role in reducing the burden of this silent disease and in view of the limited resources available, many countries have adopted certain programs to fight osteoporosis through shifting their attention towards at-risk individuals. The Iranian Multicenter Osteoporosis Study (IMOS) is one of these programs. The program aims to assess bone health and the prevalence of vitamin D deficiency in different parts of Iran with various altitudes, latitudes and lifestyle habits in a way that the results could be generalized to the country. Method- The present article presents the protocol used in the third phase of the study. It was designed based on the experiences gathered in the previous phases to overcome the shortcomings particularly subject loss. The questionnaire applied in this study was developed based on a thorough literature review of the risk factors and secondary causes of osteoporosis and was approved by an expert panel. It should be added that while the majority of the existing studies aim to study a certain aspect of osteoporosis, the present protocol provides the information needed for policy makers and researchers to study different osteoporosis-related issues. Conclusion- The authors believe the protocol, to be implemented with small modifications, can help policymakers in different parts of the world, particularly developing countries, gather accurate information on different aspects of bone health at the national level. © 2015, Academy of Medical Sciences of I.R. Iran. All rights reserved

    Biological Evaluation of a Novel Tissue Engineering Scaffold of Layered Double Hydroxides (LDHs)

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    Bone Tissue Engineering (BTE) Composed of Three Main Parts: Scaffold, Cells and Signaling Factors. Several Materials and Composites Are Suggested as a Scaffold for BTE. Biocompatibility is One of the Most Important Property of a BTE Scaffold. in This Work Synthesis of a Novel Nanocomposite Including Layered Double Hydroxides (LDH) and Gelatin is Carried Out and its Biological Properties Were Studied. the Co-Precipitation (PH=11) Method Was Used to Prepare the LDH Powder, using Calcium Nitrate, Magesium Nitrate and Aluminum Nitrate Salts as Starting Materials. the Resulted Precipitates Were Dried. X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM) Analyses Were Used to Characterize the Synthesized Powders. the Results Demonstrated the Presence of Nanocrystals of Ca-LDH and Mg-LDH as Hexagonal and Layered Morphology. the Obtained Powders Were Composed to Gelatin Via Solvent Casting Method Then Freez Dried. the Scaffold Was Prepared Via Membrane Lamination Method from the Resulted Layers that Linked Together with Gelatin as Binder. in Order to Investigate the Scaffold Cytotoxicity MTT Assay Was Done with a Osteosarcoma Cell Line. No Toxic Response Was Observed in Specimens. as a Major Result, It Was Demonstrated that the Specimen Showed a Significant Cellular Response. Then Osteosarcoma Cells Were Cultured for 7-Day and 14-Day Extract of Powders. the Composites Osteoconductivity Was Investigate with Cells Alkaline Phosphatase Extraction. the Results Demonstrated that the Ca-LDH/gelatin Composite Scaffold Has a Good Potential for Bone Tissue Engineering Applications and Mg-LDH Specimen Has a Better Osteconductivity. © (2012) Trans Tech Publications

    Dynamical aspects of mean field plane rotators and the Kuramoto model

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    The Kuramoto model has been introduced in order to describe synchronization phenomena observed in groups of cells, individuals, circuits, etc... We look at the Kuramoto model with white noise forces: in mathematical terms it is a set of N oscillators, each driven by an independent Brownian motion with a constant drift, that is each oscillator has its own frequency, which, in general, changes from one oscillator to another (these frequencies are usually taken to be random and they may be viewed as a quenched disorder). The interactions between oscillators are of long range type (mean field). We review some results on the Kuramoto model from a statistical mechanics standpoint: we give in particular necessary and sufficient conditions for reversibility and we point out a formal analogy, in the N to infinity limit, with local mean field models with conservative dynamics (an analogy that is exploited to identify in particular a Lyapunov functional in the reversible set-up). We then focus on the reversible Kuramoto model with sinusoidal interactions in the N to infinity limit and analyze the stability of the non-trivial stationary profiles arising when the interaction parameter K is larger than its critical value K_c. We provide an analysis of the linear operator describing the time evolution in a neighborhood of the synchronized profile: we exhibit a Hilbert space in which this operator has a self-adjoint extension and we establish, as our main result, a spectral gap inequality for every K>K_c.Comment: 18 pages, 1 figur

    Association between 318C/T polymorphism of the CTLA-4 gene and systemic lupus erythematosus in Iranian patients

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    Background: Cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) is an important negative regulator of T-cell response. It is a functional candidate gene connected with susceptibility to systemic lupus erythematosus (SLE). We analyzed the role of -318C/T polymorphism in the promoter region of the CTLA-4 gene in Iranian patients suffering from SLE. Methods: A total of 180 SLE patients and 304 healthy ethnically matched controls were enrolled in the study. DNA was extracted from blood samples according to the standard procedure. Polymerase chain reaction restriction fragments length polymorphism (PCR-RFLP) was used to analyze the genotype and allele frequencies of these polymorphisms. Results: The CC genotype was observed in 170 (94.5%) of the SLE patients, which was significantly different compared to the controls (251 [82.4%]; P = 0.0001, OR = 3.51 95%CI = 1.77-7.53). T allele was significantly more common in the controls (9.2%) compared to SLE patients 2.8% (P = 0.0001, OR = 0.26, 95%CI = 0.13-0.53). There was no significant correlation between different genotypes and age, gender or family history of SLE in the studied population. Conclusion: It can be concluded that -318C/T polymorphism of CTLA-4 gene might play a significant role in the development of SLE in the Iranian patients. © 2014 Asia Pacific League of Associations for Rheumatology and Wiley Publishing Asia Pty Ltd

    Protocol for a multicentre, prospective cohort study of clinical, proteomic and genomic patterns associated with osteoporosis to develop a multidimensional fracture assessment tool: the PoCOsteo Study

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    INTRODUCTION: The HORIZON 2020 project PoCOsteo aims (1) to develop a multidimensional fracture risk assessment tool which would take into account all factors known to be related to an individual's fracture risk. The fracture risk model is intended to be developed in two different populations, namely a European and a Middle Eastern one; (2) to develop a medical device, which would measure and/or quantify proteomic as well as genomic factors as present in whole blood samples collected through finger prick; (3) to test the clinical applicability and the validity of prototypes of the to be developed point of care device at both clinical centres. METHODS AND ANALYSIS: This article presents the protocol of this prospective cohort that will be carried out independently at two different centres (Division of Endocrinology and Diabetology at the Medical University of Graz (MUG) as a clinic-based cohort, and Endocrinology and Metabolism Research Institute (EMRI) at the Tehran University of Medical Sciences (TUMS) as a population-based cohort). The final aim is to develop a fracture risk assessment model, which would include clinical risk factors, biochemical markers of bone turnover, as well as specific genomic factors. The derivation cohorts will consist of individuals aged 50 years and above. The period of observation for each patient will be 12 months; an extension phase, which would last for another 2 years, is also planned. ETHICS AND DISSEMINATION: These studies are conducted in accordance with the World Medical Association Declaration of Helsinki. The Iranian part was approved by the Research Ethics Committee of EMRI, TUMS. The Austrian part was approved by the Ethics Committee of the Medical University of Graz. Based on the gathered information, a multidimensional fracture assessment tool will be designed which will later be added to the PoCOsteo device

    Global attractor and asymptotic dynamics in the Kuramoto model for coupled noisy phase oscillators

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    We study the dynamics of the large N limit of the Kuramoto model of coupled phase oscillators, subject to white noise. We introduce the notion of shadow inertial manifold and we prove their existence for this model, supporting the fact that the long term dynamics of this model is finite dimensional. Following this, we prove that the global attractor of this model takes one of two forms. When coupling strength is below a critical value, the global attractor is a single equilibrium point corresponding to an incoherent state. Conversely, when coupling strength is beyond this critical value, the global attractor is a two-dimensional disk composed of radial trajectories connecting a saddle equilibrium (the incoherent state) to an invariant closed curve of locally stable equilibria (partially synchronized state). Our analysis hinges, on the one hand, upon sharp existence and uniqueness results and their consequence for the existence of a global attractor, and, on the other hand, on the study of the dynamics in the vicinity of the incoherent and synchronized equilibria. We prove in particular non-linear stability of each synchronized equilibrium, and normal hyperbolicity of the set of such equilibria. We explore mathematically and numerically several properties of the global attractor, in particular we discuss the limit of this attractor as noise intensity decreases to zero.Comment: revised version, 28 pages, 4 figure
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