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11.
Hosseini Zohreh Habibi Najafi Mohammad Bagher Yavarmanesh Masoud Ataei-Pirkooh Angila 《International journal of peptide research and therapeutics》2020,26(2):911-919
International Journal of Peptide Research and Therapeutics - LL-37 is a 37 amino acid long cationic peptide belonging to the cathelicidin family of antimicrobial peptides. Limited investigations... 相似文献
12.
In this study, we extracted the essential oils of the stem, leaf, and flower of Achillea filipendulina, analyzed them, and studied their antibacterial properties. Of 16, 53, and 35 compounds identified in the stem, leaf, and flowers, respectively, only five are present in all three segments of the plant. The essential oil of the stem was mainly composed of neryl acetate, spathulenol, carvacrol, santolina alcohol, and trans‐caryophyllene oxide. However, the main identified components of leaf were 1,8‐cineole, camphor, ascaridole, trans‐isoascaridole, and piperitone oxide and the main components of the flower oil were ascaridole, trans‐isoascaridole, 1,8‐cineole, p‐cymene, and camphor. The extracted oil from different segments demonstrated varying antibacterial properties against both Gram‐positive and Gram‐negative bacteria, demonstrated by disk, minimum inhibitory concentration, and minimum bactericidal concentration methods. These suggest that the application of all segments of aerial parts of A. filipendulina may have a better therapeutic effect in fighting pathogenic systems. 相似文献
13.
Amin Ghafuri-Esfahani Rahman Shokri Athar Sharifi Lida Shafiee Roya Khosravi 《Preparative biochemistry & biotechnology》2020,50(8):834-841
AbstractSeveral factors may affect erythropoietin (EPO) sugar structures including designing cell culture procedure, pH, concentration of additives, dissolved oxygen, and other physicochemical parameters. In this study, we investigated the influence of changes in effective parameters and compounds on the growth rate of Chinese hamster ovary cell (CHO) cells producing recombinant EPO. Cell culture was performed at different temperature, buffering conditions, and varied concentrations of additives such as pyruvic acid, insulin, GlutaMAX, and sodium butyrate. Results indicated that the optimal temperature and pH were 37?°C and 7.2, respectively. Also, optimal concentrations for pyruvic acid, butyrate, glutamate, and insulin were obtained to be 20?mM, 1?mM, 2?mM, and 40?μg/mL, respectively. Then, cell culture was performed in microcarrier-coated spinner flasks under the optimized condition. The results showed recombinant human EPO (rhEPO) production with adequate purity. Optimization of physicochemical conditions and culture media are important factors to improve the quantity and quality of protein products. This study showed that cell growth and recombinant EPO protein production significantly increased under the optimized conditions. The results of this research can also be used in scale-up to increase the efficiency of EPO production. Abbreviations: EPO: erythropoietin; CHO cell: Chinese hamster ovary cell; rhEPO: recombinant human EPO; DMEM: modified eagle’s medium; FBS: fetal bovine serum; SDS-PAGE: sodium dodecyl sulfate–polyacrylamide gel electrophoresis; IGF-1: insulin-like growth factor 1 相似文献
14.
Sharifi Alireza Gendernalik Alex Garrity Deborah Bark David 《Biomechanics and modeling in mechanobiology》2021,20(5):2001-2012
Biomechanics and Modeling in Mechanobiology - During development, the heart begins pumping as a valveless multilayered tube capable of driving blood flow throughout the embryonic vasculature. The... 相似文献
15.
Naderi Gharehgheshlagh Soheila Fatemi Mohammad Javad Jamili Shahla Nourani Mohammad Reza Sharifi Ali Mohammad Saberi Mohsen Amini Naser Ganji Fatemeh 《International journal of peptide research and therapeutics》2021,27(1):317-328
International Journal of Peptide Research and Therapeutics - Natural compounds extracted from marine organisms consisting of biological active materials like collagen provide a major source of... 相似文献
16.
P. Rahnamay Moshtagh S. Hojati Emami Ali M. Sharifi 《Journal of physiology and biochemistry》2013,69(3):451-458
Stem cells with the ability to differentiate into insulin-producing cells (IPCs) are becoming the most promising therapy for diabetes mellitus and reduce the major limitations of availability and allogeneic rejection of beta cell transplantations. Mesenchymal stem cells (MSCs) are pluripotent stromal cells with the ability to proliferate and differentiate into a variety of cell types including endocrine cells of the pancreas. This study sought to inspect the in vitro differentiation of human adipose-derived tissue stem cells into IPCs which could provide an abundant source of cells for the purpose of diabetic cell therapy in addition to avoid immunological rejection. Adipose-derived MSCs were obtained from liposuction aspirates and induced to differentiate into insulin-secreting cells under a three-stage protocol based on a combination of low-glucose DMEM medium, β-mercaptoethanol, and nicotinamide for pre-induction and high-glucose DMEM, β-mercaptoethanol, nicotinamide, and exendin-4 for induction stages of differentiation. Differentiation was evaluated by the analysis of morphology, dithizone staining, RT-PCR, and immunocytochemistry. Morphological changes including typical islet-like cell clusters were observed by phase-contrast microscope at the end of differentiation protocol. Based on dithizone staining, differentiated cells were positive and undifferentiated cells were not stained. Furthermore, RT-PCR results confirmed the expression of insulin, PDX1, Ngn3, PAX4, and GLUT2 in differentiated cells. Moreover, insulin production by the IPCs was confirmed by immunocytochemistry analysis. It is concluded that adipose-derived MSCs could differentiate into insulin-producing cells in vitro. 相似文献
17.
Diabetic retinopathy (DR), a leading cause of vision loss and a significant source of morbidity, is the most common ocular complication of prolonged diabetes mellitus. Most therapeutic approaches address DR by preventing or destroying neovasculature; however, this fails to eliminate pathogenic causes. Mesenchymal stem cells (MSCs) are a promising candidate for cell therapy because they have unique regenerative potential and provide an option to manage retinal injuries. Transplantation of MSCs in rats with diabetes induced by streptozocin administration was shown to ameliorate DR. However, the poor viability and homing of MSCs after transplantation may reduce the efficacy of cell therapy. Intravitreal transplantation of MSCs was shown to augment vascular endothelial growth factor (VEGF). More recent studies have found a central role for VEGF in vascular lesion formation in DR and proposed blockage of VEGF as an effective approach to manage DR. Atorvastatin, a 3-hydroxy-3-methyl-glutaryl coenzyme A reductase inhibitor, has been proven to decrease VEGF production of MSCs under hypoxic conditions. It has also been demonstrated that atorvastatin increases the viability of MSCs through the adenosine monophosphate-activated protein kinase-endothelial nitric oxide synthase signaling pathway. There is also evidence that nitric oxide improves homing of MSCs by increasing chemokine-related receptor CXCR4 expression. It could be hypothesized that co-administration of MSCs with atorvastatin may be a significant step forward in development of an efficient MSC therapy of DR through preventing excess VEGF production by MSCs under hypoxic conditions as well as increasing the viability and homing of transplanted MSCs. 相似文献
18.
Mitra Kheirabadi Zohreh Sharafian Hossein Naderi-Manesh Udo Heineman Ulrich Gohlke Saman Hosseinkhani 《Biochimica et Biophysica Acta - Proteins and Proteomics》2013,1834(12):2729-2735
Firefly bioluminescence reaction in the presence of Mg2 +, ATP and molecular oxygen is carried out by luciferase. The luciferase structure alterations or modifications of assay conditions determine the bioluminescence color of firefly luciferase. Among different beetle luciferases, Phrixothrix hirtus railroad worm emits either yellow or red bioluminescence color. Sequence alignment analysis shows that the red-emitter luciferase from Phrixothrix hirtus has an additional arginine residue at 353 that is absent in other firefly luciferases. It was reported that insertion of Arg in an important flexible loop350–359 showed changes in bioluminescence color from green to red and the optimum temperature activity was also increased. To explain the color tuning mechanism of firefly luciferase, the structure of native and a mutant (E354R/356R/H431Y) of Lampyris turkestanicus luciferase is determined at 2.7 Å and 2.2 Å resolutions, respectively. The comparison of structure of both types of Lampyris turkestanicus luciferases reveals that the conformation of this flexible loop is significantly changed by addition of two Arg in this region. Moreover, its surface accessibility is affected considerably and some ionic bonds are made by addition of two positive charge residues. Furthermore, we noticed that the hydrogen bonding pattern of His431 with the flexible loop is changed by replacing this residue with Tyr at this position. Juxtaposition of a flexible loop (residues 351–359) in firefly luciferase and corresponding ionic and hydrogen bonds are essential for color emission. 相似文献
19.
Zohreh Varasteh Ola ?berg Irina Velikyan Gunnar Lindeberg Jens S?rensen Mats Larhed Gunnar Antoni Mattias Sandstr?m Vladimir Tolmachev Anna Orlova 《PloS one》2013,8(12)
Expression of the gastrin-releasing peptide receptor (GRPR) in prostate cancer suggests that this receptor can be used as a potential molecular target to visualize and treat these tumors. We have previously investigated an antagonist analog of bombesin (D-Phe-Gln-Trp-Ala-Val-Gly-His-Sta-Leu-NH2, RM26) conjugated to 1,4,7-triazacyclononane-N,N'',N''''-triacetic acid (NOTA) via a diethylene glycol (PEG2) spacer (NOTA-P2-RM26) labeled with 68Ga and 111In. We found that this conjugate has favorable properties for in vivo imaging of GRPR-expression. The focus of this study was to develop a 18F-labelled PET agent to visualize GRPR. NOTA-P2-RM26 was labeled with 18F using aluminum-fluoride chelation. Stability, in vitro binding specificity and cellular processing tests were performed. The inhibition efficiency (IC50) of the [natF]AlF-NOTA-P2-RM26 was compared to that of the natGa-loaded peptide using 125I-Tyr4-BBN as the displacement radioligand. The pharmacokinetics and in vivo binding specificity of the compound were studied. NOTA-P2-RM26 was labeled with 18F within 1 h (60-65% decay corrected radiochemical yield, 55 GBq/µmol). The radiopeptide was stable in murine serum and showed high specific binding to PC-3 cells. [natF]AlF-NOTA-P2-RM26 showed a low nanomolar inhibition efficiency (IC50=4.4±0.8 nM). The internalization rate of the tracer was low. Less than 14% of the cell-bound radioactivity was internalized after 4 h. The biodistribution of [18F]AlF-NOTA-P2-RM26 demonstrated rapid blood clearance, low liver uptake and low kidney retention. The tumor uptake at 3 h p.i. was 5.5±0.7 %ID/g, and the tumor-to-blood, -muscle and -bone ratios were 87±42, 159±47, 38±16, respectively. The uptake in tumors, pancreas and other GRPR-expressing organs was significantly reduced when excess amount of non-labeled peptide was co-injected. The low uptake in bone suggests a high in vivo stability of the Al-F bond. High contrast PET image was obtained 3 h p.i. The initial biological results suggest that [18F]AlF-NOTA-P2-RM26 is a promising candidate for PET imaging of GRPR in vivo. 相似文献
20.
Zohreh S. Tabatabayi Masoud Homayouni-Tabrizi Ali Neamati S. Ali Beyramabadi 《Journal of cellular biochemistry》2020,121(3):2677-2689
Herein, a Mn(II) complex of the N,N′-dipyridoxyl(1,4-butanediamine) (═H2L) Schiff base has been newly synthesized. The synthesized complex was characterized by several experimental methods. In addition, the density functional theory approaches were used for theoretical identification of the complex. A good agreement between the computed and experimental infrared frequencies demonstrates validity of the optimized geometry for the synthesized complex. In a N2O2 manner, two azomethine nitrogens and two phenolate oxygens of the L2− ligand are coordinated to the Mn2+ metal ion. The biological studies indicate an efficient apoptotic and antioxidant activities of the synthesized [MnL(CH3OH)2] complex on both of the HepG2 and MCF7 cancer cells. Since it has been suggested that the complex is an exclusive potent antitumor for treatment of the human breast and liver cancers. 相似文献