در هنگام جستجو کلمه در قسمت عنوان میتوانید کلمات مورد جستجو را با کاراکتر (-) جدا کنید.
کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Journal of Computational Applied Mechanics
- نوع مقاله: Journal Article
- کلمات کلیدی: dynamic model,physical model,IPMC,Smart Materials
- چکیده:
- چکیده انگلیسی: By the past two decades IPMCs have been intensively studied because of their special capabilities for actuation and sensing.This paper presents a theoretical physics based model for analyzing the behavior of IPMC sensors in fluid environments. The mechanical vibration of the IPMC strip is described by the classical Euler–Bernoulli beam theory. The model also takes in to account the physical properties of the surrounding fluid. The resulting model is an infinite-dimensional transfer function that relates the input tip displacement to the output sensing current. Further the original model is reduced to a finite-dimensional one, for pure sensing applications of IPMC sensors such as structural health monitoring. The proposed model is verified using existing experimental data. Then the effect of various parameters is investigated. The acoustics physics interface in COMSOL Multiphysics software is used for coupled modal analysis of the IPMC strip. It is shown that the effect of surrounding fluid cannot be neglected.
- انتشار مقاله: 10-03-1398
- نویسندگان: Mohammad Reza Salehi Kolahi,Hossein Moeinkhah
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Veterinary Medicine
- نوع مقاله: Journal Article
- کلمات کلیدی:
- چکیده: در این مطالعه اثرات عصاره های برگ انجیر معمولی روی مقادیر کلسترول تام سرم و کبد موشهای صحرایی که بصورت تجربی دچار هیپرلیپیدمی تغذیه ای شده بودند مورد بررسی قرار گرفت. سه عصاره برگ شامل عصاره هیدرومتانولی (تام) با غلظتهای 5/2، 5 و 10 میلی گرم بازای کیلوگرم و دو عصاره آبی آن بنام عصاره الف و عصاره ب با غلظتهای 10، 50 و 250 میلی گرم بازای کیلوگرم وزن حیوان بصورت تزریق داخل صفاقی و روزانه بمدت هشت روز در 9 گروه پنج تایی حیوانات هیپرلیپیدمیک بکار رفت. در گروههای کنترل منفی و مثبت، حیوانات به ترتیب جیره های نرمال و هیپرلیپیدمیک را همراه با تزریق روزانه سرم فیزیولوژی دریافت کردند. اثرات پایین آورنده چربی عصاره تام، روی کلسترول کبد بارزتر از اثرات آن روی سرم بود. عصاره الف عیار کلسترول را بطور معنی دار و وابسته به دوز در سرم و کبد کاهش داد. عصاره ب تاحدی اثر کاهشی روی کلسترول سرم و کبد داشت اما نتایج آن متناقض بود. آزمونهای غربالگری فیتوشیمیایی نشان داد که عصاره تام دارای مقادیر متوسطی فلاونوئید و مقادیر زیادی تانن بود که بنظر می رسد اثرات کاهنده کلسترول در این مطالعه را می توان به این مواد نسبت داد. بر اساس یافته های این مطالعه می توان نتیجه گرفت که عصاره های برگ انجیر معمولی می توانند مقادیر کلسترول را در سرم و کبد موش صحرایی هیپرلیپیدمیک کاهش دهند.
- چکیده انگلیسی: The effects of three Ficus carica leaf extracts on the total cholesterol levels (TC) of serum and liver were investigated in experimentally-induced nutritional hyperlipidemic rats. In nine treatment groups (n=5 each group), hyperlipidemic rats were treated daily with hydromethanolic (total) extract (2.5, 5, 10 mg/kg, intraperitoneal [ip]) and its aqueous fractions, namely fraction A (10, 50, 250 mg/kg, ip) and fraction B (10, 50, 250 mg/kg, ip) for eight days. In negative and positive control groups, animals received normal and hyperlipidemic diets with ip injections of normal saline, respectively. The lipid-lowering effect of total extract on liver cholesterol was more pronounced than that of serum. Fraction A caused a significant dose-dependent decrease in cholesterol levels in both the serum and the liver (p<0.05). Fraction A at dosages of 10, 50 and 250 mg/kg lowered the TC in serum from 1.40±0.26 mmol/L (mean ± standard deviation; untreated hyperlipidemic group) to 1.06±0.14, 1.04±0.07 and 0.90±0.08 mmol/L, respectively. At 50 and 250 mg/kg, it lowered the TC in liver significantly from 59.86±10.35 mg/g (untreated) to 42.61±12.08 and 37.16±5.59 mg/g, respectively. Fraction B lowered the level of TC in the serum and liver, but the results of this treatment were conflicting. Phytochemical screening showed that total extract had moderate levels of flavonoids and a large amount of tannins, which may account for the observed effects on decreasing TC levels. In conclusion, Ficus carica leaf extracts have been shown to decrease liver and serum TC levels in hyperlipidemic rats.
- انتشار مقاله: 11-10-1348
- نویسندگان: علی رسولی,Ahmad Fatemi Ardestani,Farzad Asadi,Mohammad Salehi
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Pathology
- نوع مقاله: Journal Article
- کلمات کلیدی: Viral infection,Disease Susceptibility,ABO histo-Blood group,coronavirus SARS-CoV-2
- چکیده:
- چکیده انگلیسی: Background & Objective: Coronavirus disease 2019 (COVID-19) is the most recent emerging viral disease. Defining the epidemiological aspects and factors influencing the susceptibility of the patients to COVID-19 has been an ongoing struggle. In the present study, we have investigated the connection between ABO histo-blood group phenotypes and the COVID-19.
Methods: This study was conducted on 397 patients with confirmed diagnoses of COVID-19 admitted to our center. Also, 500 individuals were selected to form the controls, all of whom had been disclosed to the same medical center in June 2019, before the onset of the outbreak.
Results: Our results demonstrated ABO histo-blood phenotypes are correlated with patients’ susceptibility to the infection. A higher rate of infection was observed among patients with the AB histo-blood group, while patients with the O histo-blood group have shown a lower rate of infection. The Rh blood group phenotype was not statistically significant in determining a patient’s vulnerability.
Conclusion: Similar to several previous studies about other viral diseases’ association with ABO histo-blood groups, we have concluded that an individual’s ABO histo-blood group phenotype and his/her susceptibility to COVID-19 are indeed connected. So far, only one research has been conducted about this association. Interestingly, while we observed a decreased vulnerability to the disease among patients with an O histo-blood group, we have reached discordant results regarding the increased susceptibility among individuals with an AB histo-blood group, unlike A histo-blood group in the previous study.- انتشار مقاله: 03-02-1399
- نویسندگان: Alireza Abdollahi,Maedeh Mahmoudi-aliabadi,Vahid Mehrtash,Bita Jafarzadeh,Mohammadreza Salehi
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Pathology
- نوع مقاله: Journal Article
- کلمات کلیدی: ELISA,Helicobacter pylori,Sero-Prevalence,Neyshabur City
- چکیده:
- چکیده انگلیسی: Backgrounds & Objective: The Helicobacter pylori prevalence has continuously decreased during recent years in Iran. The current study aimed at determining H. pylori prevalence in Neyshabur city, Northeast Iran, during 2010-2015.
Methods: The current epidemiologic survey was conducted in Neyshabur from 2010 to 2015 to determine the prevalence of H. pylori infection. A total of 11596 participants (3681 male with the mean age of 31.7±6.2 years and 7915 female with mean age of 68.3±4.7 years) were included. The enzyme-linked immunosorbent assay kits for the detection of H. pylori and Stat Fax 3200® Microplate Reader (USA) with a sensitivity of 95% and specificity of 98% were used. Titers above 12 units were considered positive for IgG, IgA, and IgM (negative <8, equivocal 8 to 12, and positive >12 U). The Chi-square t test and F test were used to analyze data.
Results: The overall IgA, IgG, and IgM seropositive samples among the study participants were 852 (7.2%), 9000 (72.8%), and 1256 (5.2%), respectively. The IgA seropositivity was significantly high among the age group above 51 years, compared with the other age groups. Moreover, the IgG and IgM seropositivity were significantly high among the age groups 41 to 50 and 31 to 40 years respectively, compared with the other age groups. There was no significant difference between male and female cases regarding IgA and IgG seropositive samples, but IgM level was significantly higher among females, compared with that of the male cases. Furthermore, there was no significant alteration in IgA, IgG, and IgM seropositivity during 2010-2014 in Neyshabur.
Conclusion: The prevalence of H. pylori in Neyshabur was high in the healthy population. Furthermore, the H. pylori prevalence did not change from 2010 to 2014 in the studied city. Effective approaches to improve health, educational, and socioeconomic status should be implemented to minimize and control H. pylori infection.- انتشار مقاله: 14-12-1394
- نویسندگان: Mohammad Salehi,Abdolmajid Ghasemian,Seyyed Khalil Shokouhi Mostafavi,Somayyeh Najafi,Hassan Rajabi Vardanjani
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Finance
- نوع مقاله: Journal Article
- کلمات کلیدی: Capital Market,Banking System,Higher education system,banking securities,development banks
- چکیده:
- چکیده انگلیسی: Optimizing the financing of Iran's higher education system faces major challenges such as smallness of the private sector, lack of a competitive market in knowledge production, the state's small role in higher education, and also the absence of new financial instruments in the capital market along with the development of the money market. As a result, the most important financing resources and major clients of academic research projects are state-run organizations, which also raise finance through tuition. Apparently, there are a few reasons why the higher education system should change its financing methods to achieve great goals. These reasons include intensified economic sanctions, declined capacity of the state to finance this sector, decreased power of families and firms to cover educational and research expenses through private budgets, and the necessity of making higher education expenses efficient with respect to the need to train the future workforce.
The method of this study is a descriptive-qualitative, which was carried out in two stages of the library and the implementation of the Delphi method by referring to 20 experts.
Aiming to introduce new instruments to make banking asset-backed securities (of facilities type) to education and research clients (families and firms), this study seeks to prove the hypothesis that the mortgage-backed securities can be employed to achieve the following goals. The first goal is to grant facilities to the students who are financially unable to pay tuition. This relieves the pressure on the Students Welfare Fund. The second goal is to grant business financing facilities to talented students. Finally, the third goal is to finance the firms that have research needs but are unable to cover the expenses through their revenues. Regarding 17 indicators, the research findings indicate that experts reached a consensus (Kendall's W= 0.702).- انتشار مقاله: 15-09-1398
- نویسندگان: Atiyeh Dadjoye Tavakoli,MohammadAli Hosseini,Mostafa Niknami,Mohammad Javad Salehi
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Basic Medical Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Peripheral blood mononuclear cells,Cystic fibrosis,CRISPR,CFTR gene,ΔF508 Mutation
- چکیده:
- چکیده انگلیسی: Objective(s): Cystic fibrosis (CF) is an inherited autosomal recessive disease that is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. The present study aimed to investigate the genetic modification of CF with ΔF508 mutation of the CFTR gene using CRISPR in peripheral blood mononuclear cells (PBMCs).
Materials and Methods: Two single guide RNAs were designed to target sequences in the CFTR gene. The transfection efficiency of PBMC cells was examined through evaluation of green fluorescent protein (GFP) expression using fluorescent microscopy. Moreover, a sgRNA-Cas9 plasmid was tested to target the CFTR gene. The ΔF508 gene modification was evaluated and confirmed by PCR and Sanger sequencing methods.
Results: Our results indicate the feasibility of site-specific gene targeting with the CRISPR/Cas9 system. 33% of the samples were corrected using CRISPR in mutant locus and confirmed by sequence blast at NCBI databases and primers outside the arm locus. CRISPR/Cas9 approach represents an efficient tool to repair the ΔF508 mutation of the CFTR gene in PBMC Cells.
Conclusion: Therefore, the CRISPR system can be highly efficient and specific and provides a powerful approach for genetic engineering of cells and model animals. Generally, the proposed method opens new insights into the treatment of human diseases.- انتشار مقاله: 10-04-1399
- نویسندگان: Sepideh Khatibi,Mohammad Reza Modaresi,Reza Kazemi Oskuee,Mohammad Salehi,Hamid Aghaei
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Basic Medical Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Testosterone,GnRH,Kisspeptin,Neurokinin B,RFRP
- چکیده:
- چکیده انگلیسی: Objective(s): Several pathological conditions are associated with hyper-production of testosterone; however, its impacts are not well understood. Hence, we evaluated the effects of supraphysiological levels of testosterone on gonadotropin-releasing hormone (GnRH) system in the hypothalamus of male rats. Also, we assessed the expression of two excitatory (kisspeptin and neurokinin-B) and two inhibitory (dynorphin and RFamide-related-peptide) neuropeptides upstream of GnRH neurons as possible routes to relay androgen information.
Materials and Methods: Gonadectomized (GDX) male rats received single injection of 100, 250 or 500 mg/kg testosterone undecanoate and three weeks later, posterior (PH) and anterior (AH) hypothalamus was dissected for evaluation of target genes using quantitative RT-PCR.
Results: We found that GnRH mRNA in the PH was high in GDX rats and 500 mg/kg testosterone reduced GnRH level expression. Finding revealed extremely high level of Kiss1 mRNA in the PH of GDX rats. However, in GDX rats treated with different levels of testosterone, Kiss1 expression was not significantly different than control. We also found that testosterone replacement increased the Kiss1 mRNA level in the AH. Moreover, neurokinin-B mRNA level in PH of GDX rats was similar to control. However, excess testosterone levels were effective in significantly inducing the down-regulation of neurokinin-B expression. The basal level of dynorphin mRNA was increased following testosterone treatments in the AH, where we found no significant difference in the level of RFamide-related-peptide mRNA between the experimental groups.
Conclusion: Excess levels of testosterone could act differently from its physiological concentration to regulate hypothalamic androgen sensitive neurons to control GnRH cell.- انتشار مقاله: 18-08-1397
- نویسندگان: Mohammad Saied Salehi,Homayoun Khazali,Fariba Mahmoudi,Mahyar Janahmadi
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Basic Medical Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Peripheral blood mononuclear cells,Cystic fibrosis,CRISPR,CFTR gene,ΔF508 Mutation
- چکیده:
- چکیده انگلیسی: Objective(s): Cystic fibrosis (CF) is an inherited autosomal recessive disease that is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. The present study aimed to investigate the genetic modification of CF with ΔF508 mutation of the CFTR gene using CRISPR in peripheral blood mononuclear cells (PBMCs).
Materials and Methods: Two single guide RNAs were designed to target sequences in the CFTR gene. The transfection efficiency of PBMC cells was examined through evaluation of green fluorescent protein (GFP) expression using fluorescent microscopy. Moreover, a sgRNA-Cas9 plasmid was tested to target the CFTR gene. The ΔF508 gene modification was evaluated and confirmed by PCR and Sanger sequencing methods.
Results: Our results indicate the feasibility of site-specific gene targeting with the CRISPR/Cas9 system. 33% of the samples were corrected using CRISPR in mutant locus and confirmed by sequence blast at NCBI databases and primers outside the arm locus. CRISPR/Cas9 approach represents an efficient tool to repair the ΔF508 mutation of the CFTR gene in PBMC Cells.
Conclusion: Therefore, the CRISPR system can be highly efficient and specific and provides a powerful approach for genetic engineering of cells and model animals. Generally, the proposed method opens new insights into the treatment of human diseases.- انتشار مقاله: 10-04-1399
- نویسندگان: Sepideh Khatibi,Mohammad Reza Modaresi,Reza Kazemi Oskuee,Mohammad Salehi,Hamid Aghaei
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Basic Medical Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Testosterone,GnRH,Kisspeptin,Neurokinin B,RFRP
- چکیده:
- چکیده انگلیسی: Objective(s): Several pathological conditions are associated with hyper-production of testosterone; however, its impacts are not well understood. Hence, we evaluated the effects of supraphysiological levels of testosterone on gonadotropin-releasing hormone (GnRH) system in the hypothalamus of male rats. Also, we assessed the expression of two excitatory (kisspeptin and neurokinin-B) and two inhibitory (dynorphin and RFamide-related-peptide) neuropeptides upstream of GnRH neurons as possible routes to relay androgen information.
Materials and Methods: Gonadectomized (GDX) male rats received single injection of 100, 250 or 500 mg/kg testosterone undecanoate and three weeks later, posterior (PH) and anterior (AH) hypothalamus was dissected for evaluation of target genes using quantitative RT-PCR.
Results: We found that GnRH mRNA in the PH was high in GDX rats and 500 mg/kg testosterone reduced GnRH level expression. Finding revealed extremely high level of Kiss1 mRNA in the PH of GDX rats. However, in GDX rats treated with different levels of testosterone, Kiss1 expression was not significantly different than control. We also found that testosterone replacement increased the Kiss1 mRNA level in the AH. Moreover, neurokinin-B mRNA level in PH of GDX rats was similar to control. However, excess testosterone levels were effective in significantly inducing the down-regulation of neurokinin-B expression. The basal level of dynorphin mRNA was increased following testosterone treatments in the AH, where we found no significant difference in the level of RFamide-related-peptide mRNA between the experimental groups.
Conclusion: Excess levels of testosterone could act differently from its physiological concentration to regulate hypothalamic androgen sensitive neurons to control GnRH cell.- انتشار مقاله: 18-08-1397
- نویسندگان: Mohammad Saied Salehi,Homayoun Khazali,Fariba Mahmoudi,Mahyar Janahmadi
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Basic Medical Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Infertility,Ovary,Epigenetics,Prooxidant-antioxidant balance,Pelvic congestion syndrome
- چکیده:
- چکیده انگلیسی: Objective(s): We intended to determine whether the ovarian varicose which is one of the common etiologies of the pelvic congestion syndrome, has the ability to interfere with the DNA methylation reprogramming in the oocyte and thereby affect the oocyte quality or not.
Materials and Methods: Varicose model was induced according to the Turner’s method in the rats. Briefly, a 20-gauge needle was placed on the left renal vein and a thread was tied over both the needle and the renal vein medial to the insertion of the ovarian vein, and then the needle was removed. Evaluation of prooxidant-antioxidant balance (PAB) was assessed using specific kits and the expression level of the DNA methyltransferase genes Dnmt1, Dnmt3a and Dnmt3L was assessed by Real-time PCR. Immunofluorescent staining for 5-methylcytosine in the oocytes evaluated the global DNA methylation.
Results: A significant PAB increase in the ovaries from varicose group was seen. Real-time PCR demonstrated a remarkable decrease in the expression of the Dnmt3a and Dnmt3L which are responsible for de novo DNA methylation in the oocytes. Immunofluorescent staining for 5-mC showed a reduction in the fluorescence intensity in the oocytes collected from the varicose group.
Conclusion: Our findings from Real-time PCR and immunocytochemistry suggest that the epigenetic parameters in the oocyte could be affected by varicose induction and these epigenetic alteration has the potential to affect the oocyte quality. We suggest that the epigenetic changes could happen in the oocytes after the induction of ovarian varicose and lead to the oocyte quality reduction or even infertility.- انتشار مقاله: 11-07-1396
- نویسندگان: Amirhossein Mohammadi,Bagher Minaei Zangi,Mahshid Delfan Azari,Rafieh Alizadeh,Mohammad Salehi,Erfan Daneshi,Mohammad Jafar Rezaei,Mehdi Abbasi
- مشاهده