Charge reduction: an efficient strategy to reduce toxicity and increase the transfection efficiency of high molecular weight polyethylenimine

Mohammad Ramezani,Reza Kazemi Oskuee,Mehdi Rezaee,Leila Gholami,Mojtaba Seddighi Gildeh 한국약제학회 2019 Journal of Pharmaceutical Investigation Vol.49 No.1

With high potency in treatment of various diseases, gene therapy is mainly hindered by lack of safe and efficient gene delivery vectors. The current study was aimed to develop an efficient non-viral vector with adequate cytotoxicity. To this end, alkylcarboxylate chains (6C, 10C, 16C) were exploited to ameliorate the characteristics of PEI 750 kDa. Briefly, alkylcarboxylate chains with three different lengths (6C, 10C, 16C) were chemically grafted to the primary amine groups of PEI 750 kDa in three percentages (10, 50, and 100%). After evaluating the physicochemical properties of prepared vectors including surface charge, size, buffering capacity, and DNA condensing, their transfection efficiency and cytotoxicity were investigated in Neuro2A cells. The polyplexes size were 158.9–264.5 nm and their zeta potentials were 14–30 mV, while their buffering capacity and DNA condensing were not significantly decreased. The highest transfection efficiency in term of C/P ratio was observed in PEI750-10C-68%, PEI750-10C-7%, and PEI750-6C-7% at C/P ratios of 2, 4, and 6, respectively. Altogether, the decanoylcarboxylate-modified PEI with medium grafting percentages showed promising results as gene delivery vector. To sum up, the modification of high molecular weight PEIs by alkylcarboxylate chains is an efficient approach for development of more efficient non-viral vectors.

Fabrication and Characterization of Fe(III) Metal-organic Frameworks Incorporating Polycaprolactone Nanofibers: Potential Scaffolds for Tissue Engineering

Mohammad Reza Ramezani,Zeinab Ansari-Asl,Elham Hoveizi,Ali Reza Kiasat 한국섬유공학회 2020 Fibers and polymers Vol.21 No.5

Fabrication of nanofibrous scaffolds of biodegradable polymers provides a great premise for several biologicalapplications. In this study, nanofibrous polycaprolactone (PCL) mats incorporating Fe-MOF (PCL/x%Fe-MOF, x=5, 10, 20)were fabricated by electrospinning technique. The Fe-MOFs were separately synthesized by the hydrothermal method andthen were added to PCL solution for preparation of nanofibrous composites. The presence of Fe-MOF in the fibers wasdemonstrated by various methods including FT-IR (Fourier-transform infrared), PXRD (powder X-ray diffraction), EDS(energy dispersive X-ray spectroscopy) mapping, SEM (scanning electron microscope), and TEM (transmission electronmicroscope). In the FT-IR spectra of the nanocomposites, the characteristic bands for the pure PCL and Fe-MOF showed nosignificant change in their positions, suggesting a weak chemical interaction with each other, although they physically mixeduniformly. Nanofibrous structure of the as-prepared nanocomposites was confirmed by SEM and TEM images. The diameterof PCL nanofibers was measured to be 369 nm. Biological investigations indicated that the experimented scaffolds includingPCL/5%Fe-MOF and PCL/10%Fe-MOF nanofibrous scaffolds provided appropriate surface and mechanical properties suchas cellular biocompatibility, high porosity, chemical stability, and optimum fiber diameter for cell adhesion, viability, andproliferation compared with PCL and PCL/20%Fe-MOF nanocomposites. Indeed, our results demonstrated that percent ofFe-MOF in the composites played a significant role in cell attachment and viability. Also, according to the implantationstudies, up to at least 4 weeks, none of the animals showed any inflammatory response. Totally, we can be claimed that themodified electrospun scaffolds have been developed for tissue engineering applications.

The Effects of Cognitive Strategy Instruction on the Reading Comprehension of Iranian EFL Learners

Mohammad Ramezani 아시아영어교육학회 2018 The Journal of Asia TEFL Vol.15 No.4

Original Articles : Causes of Visual Impairment among Patients Referred to a Visual Rehabilitation Clinic in Iran

( Alireza Ramezani ),( Maasome Pardis ),( Nasrin Rafati ),( Mohsen Kazemi Moghaddam ),( Marzieh Katibeh ),( Pooya Rostami ),( Mohammad Hossein Dehghan ),( Mohammad Ali Javadi ),( Zahra Rabbanikhah ) 대한안과학회 2012 Korean Journal of Ophthalmology Vol.26 No.2

Purpose: Epidemiologic evaluation and investigating the causes of visual impairment in any society is a matter of concern and has a direct effect on the country`s health care planning. In this study we describe causes of low vision and blindness in Iranian patients referred to rehabilitation clinics for taking vision aids. Methods: In this cross-sectional study, visual acuity was classified based on best-corrected visual acuity in the better eye according to the World Health Organization definition (blindness, visual acuity [VA]<20/400; severe visual impairment, VA<20/200-20/400; mild to moderate visual impairment, VA<20/60-20/200). The causes of blindness and low vision were determined using the 10th version of International Classification of Diseases based on the main cause in both eyes. To describe data, we used mean±SD and frequency. Results: The study included 432 patients, 65% male, with a mean age of 43.6±25.5 years (range, 3 to 92 years). Mild to moderate visual impairment, severe visual impairment and blindness were present in 122 (28.8%), 196 (46.4%) and 105 (24.8%) of the patients, respectively. The main causes of visual impairment were retinal and choroidal diseases (74.5%), optic nerve and optic tract diseases (9.8%), vitreous and globe disorders (5.3%), congenital cataract (3.1%), and glaucoma (2.6%). The distribution pattern of the causes was similar in all age subgroups. Conclusions: Diseases of the retina and choroid are the main cause of visual impairment among patients referred to an academic visual rehabilitation clinic in Iran.

풍차날개의 공력 성능 향상과 유동 박리 감소를 위한 수동 유동 제어에 대한 DES 해석

Mohammad Moshfeghi,Shahrokh Shams,Morteza Ramezani,허남건 한국전산유체공학회 2018 한국전산유체공학회지 Vol.23 No.4

Power generation of a horizontal axis wind turbine is severely dependent upon aerodynamic phenomena over the blade, especially the flow separation. Since, usually the local AoA (Angle of Attack) in the inner and middle parts of a blade is much greater than the separation onset, the blade section encounters a highly separated flow or even stall condition. Hence, flow control methods can be employed in order to reduce or weaken the negative effects of the separation. This paper investigates the effects of a recently verified passive flow control method for HAWTs via a validated three dimensional DES(Detached Eddy Simulation) of split versions of the S809 airfoil. In this research, two different airfoil families with four various split width values of 0.5, 1, 2 and 4 percent of chord length are simulated at a range of angle of attack from 0 to 25 degrees. As a result of existence of the split, flow from the high-pressure zone at the lower surfaces gets injected into the separated area over the suction surfaces. The positive or negative effect of this method is mainly dependent upon split end location on the suction surface. Direction of the jet flow with respect to the free stream and also the width of split are the other important parameters. Also, the findings reveal that in each family there exists one optimal split width for which the airfoil aerodynamic performance is enhanced remarkably.

CFD ANALYSIS OF A NEW ACTIVE FLOW CONTROL METHOD FOR WIND TURBINE AIRFOILS USING A PADDLE WHEEL INSIDE THE SPLIT OF AIRFOIL

Mohammad Moshfeghi,Amir Maleki,Morteza Ramezani,Nahmkeon Hur(허남건) 한국전산유체공학회 2021 한국전산유체공학회지 Vol.26 No.2

In the following years, the wind energy industry will maintain its surge during the last few decades. Meanwhile, horizontal axis wind turbines (HAWT) are the most prominent one among other wind turbines. Accordingly, enhancing blade aerodynamic performance should be the main part of study over this type of turbines. For this purpose, various active and passive flow control methods are being extensively investigated. Investigating new hybrid method is the main aim of this paper. Therefore, in this present study a novel idea, that uses a paddle wheel which is located inside the split, is investigated. This new configuration is based on the split method and the rotation of a paddle wheel that provides pulsatile flow inside the split. The flow then gets injected into the bulk flow over the airfoil, causing hybrid flow control effects. Optimized split geometry of S809 airfoil has been selected and then a paddle wheel is placed inside the split. First, the effect of split width on passing flow and separation zone was investigated. Second, the effect of rotational speed of the paddle is discussed. To this end, 2D CFD simulations using SST-k-ω turbulence model have been performed. The simulations have been conducted for a wide range of angles of attack (AOA). The results are discussed in the form of aerodynamics force coefficients as well as streamlines to compare the size of the separation area at higher angles of attack.

Optimizing airport service performance by spatial multi objective location allocation problem

Ramezani Abouzar,Malek Mohammad Reza,Mohammadi Nazila 대한공간정보학회 2021 Spatial Information Research Vol.29 No.3

The increase in world population and the value of time in the current period are changing the importance of air transportation. Due to increase popularity, airport officials have increased the number of flights. Because of the fact that the airports capacity is constant, airport traffic has increased. Regarding this, airport managers are looking for a solution to reduce traffic at airports and optimize the performance of service cars at the airport. The most important innovation of this research is developing a model for dynamic location of Equipment Parking Area (EPA) with optimal allocation of airport services in two different service modes. The goal of model is reducing costs and traffic and optimizing available spaces. To find optimal solution, two objective functions have been developed in the form of median and cover problems, and EPA locations have been located in a way that minimize the objective functions. The purpose of these functions are minimizing traffic at the airport and minimizing delays in flights. Using the developed model, EPA locations can be located for different time period flights and can be used to optimize the operations of the service cars without delay. The proposed model has been implemented for the Imam Khomeini International Airport and the results indicate that the number of service cars for nine flights has been decreased about 30% without any delay, as well as the amount of traffic have been decreased about 1300 meters in the first case and in 500 m in the second one.

Analgesic Effect of Topical Sodium Diclofenac before Retinal Photocoagulation for Diabetic Retinopathy: A Randomized Doublemasked Placebo-controlled Intraindividual Crossover Clinical Trial

Alireza Ramezani,Morteza Entezari,Mohammad Mehdi Shahbazi,Yosef Semnani,Homayoun Nikkhah,Mehdi Yaseri 대한안과학회 2017 Korean Journal of Ophthalmology Vol.31 No.2

Purpose: To evaluate the analgesic effect of topical sodium diclofenac 0.1% before retinal laser photocoagulationfor diabetic retinopathy. Methods: Diabetic patients who were candidates for peripheral laser photocoagulation were included in a randomized,placebo-controlled, intraindividual, two-period, and crossover clinical trial. At the first session andbased on randomization, one eye received topical sodium diclofenac 0.1% and the other eye received an artificialtear drop (as placebo) three times before laser treatment. At the second session, eyes were given thealternate drug. Patients scored their pain using visual analogue scale (max, 10 cm) at both sessions. Patientsand the surgeon were blinded to the drops given. Difference of pain level was the main outcome measure. Results: A total of 200 eyes of 100 patients were enrolled. Both treatments were matched regarding the appliedlaser. Pain sensation based on visual analogue scale was 5.6 ± 3.0 in the treated group and 5.5 ± 3.0 in thecontrol group. The calculated treatment effect was 0.15 (95% confidence interval, –0.27 to 0.58; p = 0.486). The estimated period effect was 0.24 (p = 0.530) and the carryover effect was not significant (p = 0.283). Conclusions: Pretreatment with topical sodium diclofenac 0.1% does not have any analgesic effect during peripheralretinal laser photocoagulation in diabetic patients.

Predictors and Outcomes of Vitrectomy and Silicone Oil Injection in Advanced Diabetic Retinopathy

Alireza Ramezani,Hamid Ahmadieh,Amin Rozegar,Masoud Soheilian,Morteza Entezari,Siamak Moradian,Mohammad H Dehghan,Homayoun Nikkhah,Mehdi Yaseri 대한안과학회 2017 Korean Journal of Ophthalmology Vol.31 No.3

Purpose: To evaluate visual and anatomical results and identify factors that influence vitrectomy and silicone oil(SO) injection outcomes in proliferative diabetic retinopathy (PDR). Methods: This retrospective study included 236 eyes with PDR that were undergoing vitrectomy and SO injectionwith >3-month follow-up. The primary outcomes were final best-corrected visual acuity (BCVA) and retinalattachment rate. Results: At the final visit (mean, 88 ± 58 weeks), complete, partial, and no retinal attachment were observed in86.9%, 10.6%, and 2.5% of patients, respectively. A total of 155 eyes had experienced SO removal, while 81had SO in place. The mean initial BCVA was 1.9 ± 0.7 logarithm of the minimum angle of resolution (logMAR)and significantly improved to 1.7 ± 0.8 logMAR (p = 0.001). Initial macular detachment (adjusted odds ratio[AOR], 0.25), development of iatrogenic break (AOR, 0.25), and use of heavy SO (AOR, 0.13) were independentlyassociated with a lower risk of final retinal attachment, and SO removal was associated with a higherincidence (AOR, 7.55). Better baseline BCVA was associated with a higher risk of final BCVA ≥20 / 200. Conclusions: Despite an encouraging outcome based on anatomical data in advanced PDR treated with vitrectomyand SO, the functional prognosis was not satisfying for patients. Eyes with better vision at baseline hada more favorable prognosis, whereas eyes with initial macular detachment, intraoperative iatrogenic break, orheavy SO showed more unfavorable outcomes. In selected cases, extending the time of SO use did not worsenthe prognosis.

Anticonvulsant Effect of Berberis integerrima L. Root Extracts in Mice

Hossein Hosseinzadeh,Mohammad Ramezani,Hojjat Shafaei,Elahe Taghiabadi 사단법인약침학회 2013 Journal of Acupuncture & Meridian Studies Vol.6 No.1

Berberis integerrima is a member of Berberidaceae family. Berberine is one of the main constituents of this plant, having neuroprotective effect on central nervous system diseases. In this study, the anticonvulsant activity of methanolic extract, and hydromethanolic fraction, and chloroform fraction of B integerrima was assessed. The anticonvulsant effect of B integerrima was investigated using both pentylenetetrazole (PTZ) and maximal electroshock (MES)-induced seizure models. The LD50 value of the methanolic extract was 302.676 mg/kg. In the PTZ test, methanolic extract (140 and 200 mg/kg,i.p., p < 0.01), hydromethanolic fraction (200 mg/kg, p < 0.01), and chloroform fraction (200 mg/kg, p < 0.01) increased the onset time of hind limb tonic extensions (HLTEs). The protective effect against mortality (convulsion survivors/animals tested) was 2/8 in methanolic extract, and 3/8 in hydromethanolic fraction at a dose of 200 mg/kg and in chloroform fraction at a dose of 140 mg/kg. In the MES test, this plant did not display any significant effect in reducing HLTE duration. According to phytochemical screening,methanolic extract contained alkaloids and tannins. The present study, conducted in mice, indicated that B integerrima has anticonvulsant activity in PTZ-induced seizures. It is concluded that B integerrima may be useful in petit mal epilepsy.