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Tissue engineering provides a new research field. In this new research field, cell scaffold and b... more Tissue engineering provides a new research field. In this new research field, cell scaffold and biomolecules are used to create an extended landscape in restoration, repair and maintenance of tissues. In this study, nano properties of polymer scaffolds for tissue engineering purposes are discussed. PLLA polymer scaffold was created using electrospinning technique, chloroform solvent and DMF. Then the surface of scaffold was treated to improve biodegradability. Scaffold was investigated in terms of surface morphological characteristics, biodegradablility, porosity and pore size. For this purpose, porosity measurements with Archimedes law, biodegradablility test and scanning electron microscopy study were performed. Degradation rate of scaffold is high because there are small pores and scaffold degradation rate is proportional to the time. The most important factor in the biodegradable scaffold is direct relationship between the amount of biodegradable scaffold and water absorption by the scaffold. Evaluation of cell growth and increased cell growth in the presence of nano-scaffold showed the confirmed the biocompatibility of nano-scaffold. It indicated high porosity of 90/75 percent and internal tissue growth.The overall results showed that PLLA nano-scaffold polymer synthesized with electrospinning technique is a good candidate for tissue engineering.

Pythium irregulare oomycetes adapts with environmental changes including crude oil concentration ... more Pythium irregulare oomycetes adapts with environmental changes including crude oil concentration by changing the composition of lipids in the cytoplasmic membrane and providing the required characteristics for adaptation in improper and stressful environmental situations. It was found that cultivation of Pythium irregulare LX oomycetes in the nutrient media with different concentrations of crude oil with 1.0, 2.0, 3.0, 5.0 and 10.0 (%), incubated for 5 days at 26-28°C on a rotary shaker (200 rpm) in aerobic conditions and deep culturing caused an increase in the lipid content and the unsaturation degree of fatty acids, confirming the correspondence between the increase of polar lipid/free sterol in the composition of membrane lipids' ratio and that of polar lipids in general lipid fractions. Represented data shows that the process of adaptation of oomycetes to a stressful situation created with crude oil motivated the increase of the rate of membrane phospholipids with a high quantity of unsaturated fatty acids.

Determination level of dopamine (DA) is very important in medicine and disease diagnostic. In pre... more Determination level of dopamine (DA) is very important in medicine and disease diagnostic. In presented research, a biosensor designed based on catalase (CAT) and modified carbon paste electrode (CPE) with zinc oxide (ZnO) nanoparticles for Determination level of dopamine by electrochemical methods. Synthesized ZnO nanoparticles were studied by X-ray diffraction (XRD), UV-visible spectrophotometer and atomic force microscopy (AFM). Electrochemical studies were done with cyclic voltammetry (CV) and constant potential amperometry (CPA) experiments. A pair of welldefined redox peaks was observed at the CAT / ZnO Nps/ CPE with The formal potential (E o ) equal to + (92.5 ± 1) mV. Zinc oxide nanoparticles could play a key role in creates the CAT CV response and facile electron transfer between CAT and CPE. The CAT / ZnO Nps/ CPE showed a good sensitive state towards oxidation of DA. The designed biosensor showed a good stability and retains its 91% activity after 21 days.

Surfactin is one of the most powerful biosurfactants that has been known so far. It is an acidic ... more Surfactin is one of the most powerful biosurfactants that has been known so far. It is an acidic cyclic nonribosomal lipoheptapeptide that is produced by Bacillus subtilis. In this presentation we investigated different properties of surfactin C-15. The nanomicelle forming ability of surfactin C-15 in different aqueous environments with various ionic strengths was studied by scanning electron microscope. Surfactin second structure was investigated by Far-UV CD spectrum. Its hemolytic activity and cytotoxicity were measured by hemolysis and MTT assays, respectively. Surfactin formed spherical nanomicelles in distilled water (pH = 7.4) and amorphous nanomicelles in PBS buffer (pH = 7.4). The hemolysis assay results indicated that HC 50 of surfactin was 47 μM. Surfactin C-15 arrested growth of human cervix cancer HeLa cell line in a time-and dosage-dependent method, so that its IC 50 at 16, 24, and 48h were 86.9, 73.1, and 50.2 μM, respectively.

Purpose: With regard to the protective effect of vitamin D against colorectal cancer (CRC), we ev... more Purpose: With regard to the protective effect of vitamin D against colorectal cancer (CRC), we evaluated genetic variants that might influence vitamin D metabolism: vitamin D receptor (VDR), vitamin D binding protein (GC), vitamin D 25-hydroxylase (CYP2R1), and vitamin D 25-hydroxy 1-alpha hydroxylase (CYP27B1). Materials and Methods: A total of 657 subjects, including 303 cases with CRC and 354 controls were enrolled in this case-control study. All 657 were genotyped for the four gene variants using PCR-RFLP methods. Results: In this study, no significant difference was observed for VDR (rs2238136), GC (rs4588), CYP2R1 (rs12794714), and CYP27B1 (rs3782130) gene variants in either genotype or allele frequencies between the cases with CRC and the controls and this lack of difference remained even after adjustment for age, BMI, sex, smoking status, NSAID use, and family history of CRC. Furthermore, no evidence for effect modification of the variants and CRC by BMI, sex, or tumor site was observed. Conclusions: Our findings do not support a role for VDR, GC, and CYP27B1 genes in CRC risk in our Iranian population. Another interesting finding, which to our knowledge has not been reported previously, was the lack of association with the CYP2R1 gene polymorphism. Nonetheless, our findings require confirmation and possible roles of vitamin D metabolism-related genes in carcinogenesis need to be further investigated.

A b s t r a c t Poly lactic acid-co-poly ethylene glycol-co-Poly lactic acid (PLA-PEG-PLA) co-pol... more A b s t r a c t Poly lactic acid-co-poly ethylene glycol-co-Poly lactic acid (PLA-PEG-PLA) co-polymer was synthesized and after determination of its biological properties was used for intracellular delivery of poor soluble peptide drug, gramicidin. Toxicity of this polymer on LNCaP cell line was determined by MTT assay. Treatment of cells with fluorescein isothiocyanate (FITC) loaded nanoparticles and fluorescence microscopy indicates ability of this carrier for intracellular delivery. PLA-PEG-PLA nanoparticles containing poor soluble peptide drug, gramicidin, was prepared by solvent evaporation method. In order to confirm loading of gramicidin on PLA-PEG-PLA nanoparticles, FT-IR, spectrofluoremeteric, circular dichroism (CD), and scanning electron microscopy (SEM) studies were carried out. Our studies revealed treatment of prostate cancer cell line, LNCaP, with gramicidin loaded nanoparticles was more effective than gramicidin alone in killing cancer cells.

We investigated synthesis of zirconia nanoparticles (Nps) and their ameliorative roles as additiv... more We investigated synthesis of zirconia nanoparticles (Nps) and their ameliorative roles as additives concrete structures. Synthesized Zirconia Nps were studied with X-ray diffraction (XRD), UV-visible spectrophotometer, and transmission electron microscope (TEM). We used standard Portland cement in related experiment Concrete Structures. e experimental or E series (E1–E4) mixtures were prepared with different amounts of ZrO2 Nps with an average particle size of 20 nm. e experimental mixtures were prepared 0.125, 0.25, 0.5 and 2.0% ZrO2 Nps/cement by weight. e modi�ed cement with ZrO2 nanoparticles was studied with split tensile strength, �exural strength and setting time methods. �inal results showed that Zirconia Nps could be used for their Ameliorative roles as Additives Concrete Structures.

Background & Objectives: Polymers as drug carriers are recent advances in drug delivery and led t... more Background & Objectives: Polymers as drug carriers are recent advances in drug delivery and led to the new advent field that called polymer treatment. In the present study, the toxic and teratogenic effects of BDP18 were evaluated against chicken embryos as a model. Methods: The BDP18 tri-block copolymer (PLA-PEG2000-PLA) was synthesized. The compound solution was injected in triplicate examination, in the air sac of the eggs, at third day of incubation, and survived fraction of the embryos and Morphological and skeletal changes were recorded. Results: The survived fraction of the embryos depends on the compound concentration. In concentration of 20 mg/ml, 33.3% of the embryos were survived and the LD 50 was 10.87 mg/egg. Morphological study of the treated embryos showed no abnormalities in embryos, and skeletal staining showed the deletion of caudal vertebrate in high concentration. Conclusion: The BDP18 copolymer had low toxic and teratogenic effects against the embryos, but it caused the deletion of caudal vertebrate at concentrations above the threshold (10 mg/ml). This polymer can be used as an effective drug-release system in low concentrations.

Journal of Rafsanjan University of Medical Sciences, May 1, 2021

PubMed, Jul 1, 2020

Purpose Nonalcoholic fatty liver disease (NAFLD) is an increasing global health concern defined b... more Purpose Nonalcoholic fatty liver disease (NAFLD) is an increasing global health concern defined by excessive hepatic fat content in the absence of excessive alcohol consumption. Regarding the key role of insulin and insulin resistance in NAFLD, we investigated whether insulin receptor substrate 1 (IRS1) and insulin receptor substrate 2 (IRS2) gene variants were associated with NAFLD risk. Methods In this case-control study, 305 subjects including 151 cases with biopsy-proven NAFLD and 154 controls were enrolled. All the subjects were genotyped for IRS1 (rs1801278) and IRS2 (rs2289046) gene variants using PCR-RFLP method. Results Our findings showed that the IRS2 rs2289046 "GG+AG" genotype compared with "AA" genotype to be a marker of decreased NAFLD susceptibility and the difference remained significant even after adjustment for confounding factors including age, BMI, sex, smoking status, systolic blood pressure, and diastolic blood pressure (P=0.014; OR=0.50, 95%CI= 0.29-0.87). Furthermore, the IRS2 "G" allele was significantly underrepresented in the cases with NAFLD than controls (P=0.026 ; OR=0.62, 95%CI=0.41-0.94). However, no significant difference was found for IRS1 rs1801278 gene variant. Conclusions This study suggests, for the first time, that the IRS2 gene rs2289046 variant may play a role in NAFLD susceptibility. Nevertheless, this observation warrants further investigations in other populations.

Surface decontamination is an important issue in different areas like medicine and food industry.... more Surface decontamination is an important issue in different areas like medicine and food industry. Traditional methods of sterilization have disadvantages as thermal effect, producing toxic and chemical residues. In our research we have presented an applicable and outstanding device for surface sterilization. Cold atmospheric plasma method is suitable for the treatment of heat sensitive and the objects that are vulnerable to vacuum. The dielectric barrier discharge (DBD) is a low temperature and atmospheric pressure plasma source that is created between two conductive electrodes connected to an ac power supply. At least, one of the electrodes is covered by the dielectric layer. DBD due to its low temperature, atmospheric pressure and being non-equilibrium plasma has many applications in industry, chemistry and medicine. In order to study the effect of DBD plasma on bacteria, we study its inactivating influence on E. coli. These bacteria are important in the food industry, hospital infections and burning and chronic ulcer`s infection. The effects of the exposure time and applied voltage are studied. The mechanism of sterilization is studied among some experiments. Also the tests of ATP assay, AFM and spectrometry are done and the results of the tests and experiments are presented. Consequently, the results demonstrate that this method is capable in surface sterilizations in a fast and safe situation. We also observed that UV radiation, heat and electric field are not the effective agents in sterilization mechanism and reactive species such as Ozone, free radicals and charged particles are the main agents Keywords :Atmospheric plasma, ATP, AFM, Coronal barrier discharge, DBD, E. coli, Non-thermal plasma, Sterilization.

New Cellular and Molecular Biotechnology Journal, Oct 15, 2012

The Neuroscience Journal of Shefaye Khatam, Jul 1, 2022

Basic & Clinical Cancer Research, Jul 12, 2022

Iranian Journal of Reproductive Medicine, 2015

Background: Vitamin D and insulin play an important role in susceptibility to polycystic ovary sy... more Background: Vitamin D and insulin play an important role in susceptibility to polycystic ovary syndrome (PCOS), and therefore vitamin D receptor (VDR), parathyroid hormone (PTH), and insulin receptor (INSR) gene variants might be involved in the pathogenesis of PCOS. Objective: The present study was designed to investigate the possible associations between polymorphisms in VDR, PTH, and INSR genes and the risk of PCOS. Materials and Methods: VDR, PTH, and INSR gene variants were genotyped in 35 women with PCOS and 35 controls using Polymerase chain reaction-Restriction fragment length polymorphism method. Furthermore, serum levels of glucose and insulin were measured in all participants. Results: No significant differences were observed for the VDR FokI, VDR Tru9I, VDR TaqI, PTH DraII, INSR NsiI, and INSR PmlI gene polymorphisms between the women with PCOS and controls. However, after adjustment for confounding factors, the VDR BsmI "Bb" genotype and the VDR ApaI "Aa" genotype were significantly under transmitted to the patients (p= 0.016; OR= 0.250; 95% CI= 0.081-0.769, and p= 0.017; OR= 0.260; 95% CI= 0.086-0.788, respectively). Furthermore, in the women with PCOS, insulin levels were lower in the participants with the INSR NsiI "NN" genotype compared with those with the "Nn + nn" genotypes (P= 0.045). Conclusion: The results showed an association between the VDR gene BsmI and ApaI polymorphisms and PCOS risk. These data also indicated that the INSR "NN" genotype was a marker of decreased insulin in women with PCOS. Our findings, however, do not lend support to the hypothesis that PTH gene DraII variant plays a role in susceptibility to PCOS.

Journal of Chemical Neuroanatomy, Jul 1, 2023

Iranian Journal of Blood and Cancer, Jun 1, 2022

Gene, cell and tissue, Apr 27, 2021

Saudi journal of medicine, Mar 22, 2022

DOAJ (DOAJ: Directory of Open Access Journals), Jul 1, 2021

Tissue engineering started a new field of study which has made great view in renewal, repairing a... more Tissue engineering started a new field of study which has made great view in renewal, repairing and keeping the function of different tissue especially bone tissue, by the use of cells, scaffold and biomolecules. Nano scaffold of PLLA polymer is made by means of electro-spinning method. Nanoscaffold was examined for surface feature, biodegradability, percentage of porosities and Size of pores. To prove the stem cell character of detached cells from venous tissue, cells were examined by flowcytometry for cell makers by which they were positive on CD90, CD105 and negative CD45 marker. Humane mesenchymal stem cells were cultured on PLLA nano scaffold. Nano scaffold having these cells, where treated with bone differentiation medium for 21 days and some samples were treated with different dosage of insulin. On day 21 alizarin red and von kossa staining was performed for treated cells. Observation of cells after getting stained, showed the precipitation of calcium in extra cellular matrix .The nano scaffold having differentiated cells spread black in von kossa and red in alizarin red Because of calcium precipitates. Differentiating to bone in high concentration was hardly seen in samples containing different insulin dosages and low glucose.SEM supported the calcium precipitation in nano scaffolds having cells differentiated to bone tissue. Observations of SEM showed that lower insulin concentration has better effect on differentiation of bone cells. According to gained results, concentration as 4IU of insulin suggested as proper concentration for bone cells differentiation on PLLA nano scaffolds.

Annals of Biological Research, 2013

Ufuq-i Dānish, Oct 1, 2019

Inorganica Chimica Acta, 2019

Abstract Copper(II), Nickel(II) and Cobalt(III) complexes with Schiff base ligands derived from h... more Abstract Copper(II), Nickel(II) and Cobalt(III) complexes with Schiff base ligands derived from hydrazone, (HL1 = (E)-N′-(pyridin-2-ylmethylene)benzohydrazide, H2L2 = (E)-2-(2-hydroxybenzylidene)hydrazine-1-carboxamide and HL3 = (E)-2-(pyridin-2-ylmethylene)hydrazine-1-carboxamide, were synthesized and spectroscopically characterized by FT-IR, 1H NMR, UV–Vis spectroscopy, X-ray crystallography and cyclic voltammetry. The synthesized compounds have been screened for their antibacterial activities against the bacterial species E. coli, K. pneumonia (Gram-negative) and S. aureus, B. subtilis (Gram-positive) by minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) methods. In vitro anticancer studies of the ligands and coordination compounds (1–3) using MTT assay was also done. Results show that the complexes (1–3) have higher antibacterial and anticancer activities than the respective free ligands.

Inorganica Chimica Acta, 2016