Numerical simulation of hemodynamic parameters of turbulent and pulsatile blood flow in flexible artery with single and double stenoses

Mehdi Jahangiri,Mohsen Saghafian,Mahmood Reza Sadeghi 대한기계학회 2015 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.29 No.8

This article investigates the pulsatile and turbulent blood flows in flexible artery with single and double stenoses. The changes in pressuredrop, mean wall shear stress (WSS), radial displacement of the artery, and oscillating shear index are investigated. Similar to experimentaldata, the results of the present study show that a laminar flow occurs for stenosis of up to 70%, and for 80% stenosis the flowis turbulent. The mean WSS analysis shows that assuming the flow is laminar causes more errors than assuming the walls are solid. Thecomparison of the results for single stenosis with those for double stenosis reveals that the dilation in the arterial walls in double stenosesis much more common than in single stenosis. Therefore, the maximum mean WSS in double stenoses is less than that in single stenosis. The results also indicate that the axial pressure drop in double stenoses is higher than that in single stenosis.

Numerical simulation of non-Newtonian models effect on hemodynamic factors of pulsatile blood flow in elastic stenosed artery

Mehdi Jahangiri,Mohsen Saghafian,Mahmood Reza Sadeghi 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.2

Atherosclerosis develops due to different hemodynamic factors, among which time-averaged Wall shear stress (mean WSS) and Oscillatory shear index (OSI) are two of the most important. These two factors not only depend on flow geometry, but are also influenced by rheological characteristics of blood. Since analytical solutions are limited to simple problems and since experimental tests are costly and time consuming, CFD solutions been prominently and effectively used to solve such problems. We conducted a numerical study via ADINA 8.8 software on the non-Newtonian pulsatile flow of blood through an elastic blood artery with single and consecutive stenosis. The studied stenosis cross sectional area was 70 % that of the unstenosed artery. The single stenosis results were compared with the consecutive stenosis results. The five non-Newtonian flow models, the Carreau model, the Carreau-Yasuda model, the modified Casson model, the power-law model, and the generalized power-law model, were used to model the non-Newtonian blood flow. The obtained results showed that increasing the number of stenoses would lead to reduced length of the oscillatory area after the first stenosis, thus forming another oscillatory area with a larger length after the second stenosis. Thus, a consecutive stenosis would develop a larger disease prone area. Upon examining the mean WSS and OSI, we found that, as compared with the other models, the modified Casson model and the power-law model produced predictions for the most extent of damage to endothelial cells and the most disease prone areas, respectively.

Approximated 3D non-homogeneous model for the buckling and vibration analysis of femur bone with femoral defects

Mobasseri, Saleh,Sadeghi, Mehdi,Janghorban, Maziar,Tounsi, Abdelouahed Techno-Press 2020 Biomaterials and Biomechanics in Bioengineering Vol.5 No.1

We carry the knowledge that the skeleton bones of the human body are not always without defects and some various defects could occur in them. In the present paper, as the first endeavor, free vibration and buckling analysis of femur bones with femoral defects are investigated. A major strength of this study is the modeling of defects in femur bones. Materialise Mimics software is adopted to model the bone geometry and the SOLIDWORKS software is used to generate the defects in bones. Next, the ABAQUS software is employed to study the behaviors of bones with defects.

Reanalysis of discarded blastocysts for autosomal aneuploidy after sex selection in cleavage-stage embryos

Ebrahimian, Neda,Montazeri, Fatemeh,Sadeghi, Mohammad Reza,Kalantar, Seyed Mehdi,Gilany, Kambiz,Khalili, Mohannad Ali The Korean Society for Reproductive Medicine 2020 Clinical and Experimental Reproductive Medicine Vol.47 No.4

Objective: The goal of the present study was to investigate the rate of chromosomal aneuploidies in surplus embryos after sex determination at the cleavage stage. Then, the same chromosomal aneuploidies were evaluated in blastocysts after extended culture. Methods: Sixty-eight surplus embryos were biopsied at the cleavage stage and incubated for an additional 3 days to allow them to reach the blastocyst stage. The embryos were reanalyzed via fluorescence in situ hybridization (FISH) to examine eight chromosomes (13, 15, 16, 18, 21, 22, X, and Y) in both cleavage-stage embryos and blastocysts. Results: Although the total abnormality rate was lower in blastocysts (32.35%) than in cleavage-stage embryos (45.58%), the difference was not significant (p=0.113). However, when we restricted the analysis to autosomal abnormalities, we observed a significant difference in the abnormality rate between the cleavage-stage embryos (44.11%) and the blastocysts (17.64%, p=0.008). A higher rate of sex chromosomal abnormalities was also observed in cleavage-stage embryos (29.4%) than in blastocysts (14.70%, p=0.038). Conclusion: The data indicated that embryo biopsy should be conducted at the blastocyst stage rather than the cleavage stage. The results also emphasized that examination of common chromosomal aneuploidies apart from sex selection cycles can be conducted in the blastocyst stage with the FISH method.

Associations between a health-promoting lifestyle and quality of life among adults with beta-thalassemia major

Aghbabak Maheri,Roya Sadeghi,Davoud Shojaeizadeh,Azar Tol,Mehdi Yaseri,Mojtaba Ebrahimi 한국역학회 2016 Epidemiology and Health Vol.38 No.-

OBJECTIVES: A health-promoting lifestyle (HPL) is a factor that affects the quality of life (QoL) in patients with beta-thalassemia (β-thalassemia). Due to the lack of studies of this issue, this study aimed to determine the association between HPL and QoL among adults with β-thalassemia. METHODS: This cross-sectional (descriptive-analytic) study was conducted among 389 adult patients with β-thalassemia in Tehran, Iran. The research instrument included a questionnaire consisting of three parts: demographic items, the Short-Form Health Survey and the Health-Promoting Lifestyle Profile. The data were analyzed using SPSS version 23.0. The results were considered significant at the conventional p<0.05 level. RESULTS: The mean age of the participants was 30.2±8.3 years. The mean score of the HPL dimensions was 127.28±21.53, and the mean score of the QoL domains was 61.44±23.38. The highest and the lowest mean scores of the HPL dimensions were found for spiritual growth (23.96±5.74) and physical activity (11.32±3.95), respectively. The QoL scores in all three domains (total, physical component summary score, and mental component summary score) were moderate. Health responsibility, physical activity, spiritual growth, and interpersonal relations were significant predictive factors of QoL in adults with β-thalassemia; these four dimensions explained 37.9% of the variance in QoL. CONCLUSIONS: QoL and HPL were not at acceptable levels among patients with thalassemia. Therefore, educational interventions emphasizing spiritual growth, physical activity, and interpersonal relations are necessary for patients with thalassemia.

A Fixed Point Approach to Stability of Quintic Functional Equations in Modular Spaces

GHAEMI, MOHAMMAD BAGHER,CHOUBIN, MEHDI,SADEGHI, GHADIR,GORDJI, MADJID ESHAGHI Department of Mathematics 2015 Kyungpook mathematical journal Vol.55 No.2

In this paper, we present a fixed point method to prove generalized Hyers-Ulam stability of the systems of quadratic-cubic functional equations with constant coefficients in modular spaces.

Depression, Anxiety, and Perceived Social Support among Adults with Beta-Thalassemia Major: Cross-Sectional Study

Aghbabak Maheri,Roya Sadeghi,Davoud Shojaeizadeh,Azar Tol,Mehdi Yaseri,Alireza Rohban 대한가정의학회 2018 Korean Journal of Family Medicine Vol.39 No.2

Background: Considering the high prevalence of depression and anxiety among thalassemia patients and the role of social support in preventing mental disorders, this study aimed to determine prevalence of depression, anxiety, and perceived social support (PSS) among adults with beta-thalassemia major.Methods: This cross-sectional study was performed with 389 adults with beta-thalassemia major. Data were col-lected via a questionnaire consisting of three parts: demographic and medical information, the Persian version of the hospital anxiety and depression scale, and the Persian version of the Multidimensional Scale of Perceived So-cial Support. Data were analyzed using IBM SPSS ver. 23.0 (IBM Corp., Armonk, NY, USA) through analytical statis-tics (independent-samples t-test, one-way analysis of variance, Pearson correlation coefficient, and multilevel lin-ear regression), and the results less than 0.05 were considered to be significant.Results: The mean scores of depression, anxiety, and PSS of patients were 7.42±3.17, 7.47±4.35, and 41.8±8.64, re-spectively. Of 389 patients, 19.8% had depression and 23.7% had an anxiety disorder. Relationships of depression and anxiety with age, the level of education, job, and family income were statistically significant, as were those of PSS with age, thalassemia center, family income, job, and the level of education. PSS from family, friends, and sig-nificant others were the significant predictive factors of depression and anxiety among adult patients with beta-thalassemia major.Conclusion: Considering the PSS as a factor influencing the reduction in depression and anxiety in thalassemia pa-tients, social support from the social networks (spouse, family members, friends, and healthcare workers) should be integrated with interventions that are designed to improve the mental and physical health of thalassemia pa-tients.

Evaluation of thermal stability of confectionary sunflower protein isolate and its effect on nanoparticulation and particle size of the produced nanoparticles

Laleh Mehryar,Mohsen Esmaiili,Fariba Zeynali,Rohollah Sadeghi,Mehdi Imani 한국식품과학회 2017 Food Science and Biotechnology Vol.26 No.3

In this study, the effect of different defatting conditions on heat stability of confectionary sunflower protein isolate (SnPI) and the particle size of the produced nanoparticles was investigated. The evaluated factors included temperatures of defatting (40, 50, and 60 C), time of defatting (2, 6, and 10 h), and the amount of activated carbon (0, 25, and 50% of sample weight). The results of the central composite design showed a significant effect (P\0.05) among the studied factors, where denaturation temperature and particle size of SnPI nanoparticles were found to be in the ranges of 75.05–89.12 C and 268–1594 nm, respectively. Moreover, the interaction of activated carbon with temperature and time of defatting proved to be influential factors for the heat stability of confectionary SnPI.

Dynamical Analysis of Yeast Protein Interaction Network During the Sake Brewing Process

Mitra Mirzarezaee,Babak N. Araabi,Mehdi Sadeghi 한국미생물학회 2011 The journal of microbiology Vol.49 No.6

Proteins interact with each other for performing essential functions of an organism. They change partners to get involved in various processes at different times or locations. Studying variations of protein interactions within a specific process would help better understand the dynamic features of the protein interactions and their functions. We studied the protein interaction network of Saccharomyces cerevisiae (yeast) during the brewing of Japanese sake. In this process, yeast cells are exposed to several stresses. Analysis of protein interaction networks of yeast during this process helps to understand how protein interactions of yeast change during the sake brewing process. We used gene expression profiles of yeast cells for this purpose. Results of our experiments revealed some characteristics and behaviors of yeast hubs and non-hubs and their dynamical changes during the brewing process. We found that just a small portion of the proteins (12.8 to 21.6%) is responsible for the functional changes of the proteins in the sake brewing process. The changes in the number of edges and hubs of the yeast protein interaction networks increase in the first stages of the process and it then decreases at the final stages.

Modification of Substrate Inhibition of Synaptosomal Acetylcholinesterase by Cardiotoxins

( Seyed Omid Ranaei Siadat ),( Gholam Hosein Riazi ),( Mehdi Sadeghi ),( Long Sen Chang ),( Shinne Ren Lin ),( Peyman Eghtesadi Araghi ),( Gholam Hossein Hakimelahi ),( Ali Akbar Moosavi Movahedi ) 생화학분자생물학회 2004 BMB Reports Vol.37 No.3

Different types of cardiotoxin (I-V and n) were isolated and purified from the venom of the Taiwan cobra (Naja naja atra). The effects of these cardiotoxins were studied on membrane-bound acetylcholinesterase, which was isolated from a sheep`s brain cortex. The results showed that cardiotoxins I-III, V, and n activated the enzyme by modification of substrate inhibition, but cardiotoxin IV`s reaction was different. The inhibition and activation of acetylcholinesterase were linked to the functions of the hydrophobicity index, presence of a cationic cluster, and the accessible arginine residue. Our results indicate that Cardiotoxins have neither a cationic cluster nor an argininge residue in their surface area of loop I; therefore, in contrast to fasciculin, cardiotoxins are attached by loop II to the peripheral site of the enzyme. As a result, fasciculin seems to stabilize nonfunctional conformation, but cardiotoxins seem to stabilize the functional conformation of the enzyme. Based on our experimental and theoretical findings, similar secondary and tertiary structures of cardiotoxins and fasciculin seem to have an opposite function once they interact with acetylcholinesterase. s