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21.
Farzaneh Farivar Ali Akbar Moosavi-Movahedi Maryam Salami Mousa Bohlooli Amir Niasari-Naslaji 《Cell biochemistry and biophysics》2013,67(2):727-734
Albumin is a multifunctional non-glycosylated, negatively charged plasma protein, with extraordinary ligand-binding and transport properties, antioxidant functions, and enzymatic activities. Physiologically, albumin transports free fatty acids in plasma and contributes in maintaining colloid osmotic pressure. Recent progresses in using albumin as a versatile protein carrier for drug targeting and for improving the pharmacokinetic profile of peptide or protein-based drugs, increased the attempts for improving albumin stability. Studying the thermal stability of camel albumin may provide us not only new clues for designing recombinant albumins, but also molecular insights on camel physiology. This study aims to determine the thermal stability of camel albumin. Fatted camel serum albumin (FCSA) was purified from blood via combination of Cohn’s method and anion-exchange chromatography. Activated charcoal treatment was used to obtain defatted camel serum albumin (CSA). Fluorescence spectroscopy and differential scanning calorimetry (DSC) were used to study thermal denaturation of this protein. The set of fluorescence spectra were deconvoluted using the convex constraint analysis method (CCA). The results from deconvolution of fluorescence spectroscopy and DSC showed three and two components for CSA and FCSA, respectively. The bimodal DSC transition can be attributed to a crevice between domains I and II and formation of two independent thermodynamic domains. The crevice formation can be prevented by fatty acid binding between domains I and II. The calculated values of ?H v/?H cal, approximately 0.4 for CSA and near 1 for FCSA, confirmed the presence of at least one intermediate in thermal unfolding of CSA and the absence of the intermediate for FCSA. The obtained midpoint transition temperature (T m) of FCSA was about 20 °C higher than that of CSA. Such enormous stabilizing effect may be attributed to the fact that fatty acid serves as glue which preserves different domains beside each other and prevents formation of the mentioned intermediate. 相似文献
22.
Ulviye Acar Çevik Ismail Celik Ufuk İnce Zahra Maryam Iqrar Ahmad Harun Patel Yusuf Özkay Zafer Asım Kaplancıklı 《化学与生物多样性》2023,20(3):e202201146
In this work, the synthesis, characterization, and biological activities of a new series of 1,3,4-thiadiazole derivatives were investigated. The structures of final compounds were identified using 1H-NMR, 13C-NMR, elemental analysis, and HRMS. All the new synthesized compounds were then screened for their antimicrobial activity against four types of pathogenic bacteria and one fungal strain, by application of the MIC assays, using Ampicilin, Gentamycin, Vancomycin, and Fluconazole as standards. Among the compounds, the MIC values of 4 and 8 μg/mL of the compounds 3f and 3g , respectively, are remarkable and indicate that these compounds are good candidates for antifungal activity. The docking experiments were used to identify the binding forms of produced ligands with sterol 14-demethylase to acquire insight into relevant proteins. The MD performed about 100 ns simulations to validate selected compounds’ theoretical studies. Finally, using density functional theory (DFT) to predict reactivity, the chemical characteristics and quantum factors of synthesized compounds were computed. These results were then correlated with the experimental data. Furthermore, computational estimation was performed to predict the ADME properties of the most active compound 3f . 相似文献
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Mahinpour R Riazi G Shokrgozar MA Sarbolouki MN Ahmadian S Douraghi M Hadi Alijanvand H Azadmanesh K Heidari M Naghdi Gheshlaghi Z Moosavi-Movahedi AA 《Cell biology international》2012,36(4):403-408
Arsenical compounds exhibit a differential toxicity to cancer cells. Microtubules are a primary target of a number of anticancer drugs, such as arsenical compounds. The interaction of 1-NAA (1-naphthylarsonic acid) has been investigated on microtubule polymerization under in vitro and cellular conditions. Microtubules were extracted from sheep brain. Transmission electron microscopy was used to show microtubule structure in the presence of 1-NAA. Computational docking method was applied for the discovery of ligand-binding sites on the microtubular proteins. Proliferation of HeLa cells and HF2 (human foreskin fibroblasts) was measured by the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide] assay method following their incubation with 1-NAA. Fluorescence microscopic labelling was done with the help of α-tubulin monoclonal antibody and Tunel kit was used to investigate the apoptotic effects of 1-NAA on the HeLa cells. 1-NAA inhibits the tubulin polymerization by the formation of abnormal polymers having high affinity to the inner cell wall. 相似文献
25.
Tohidi M Ghasemi A Hadaegh F Arbabi S Hosseini Isfahani F 《Biological trace element research》2011,143(2):835-843
This study aims at determining the association between markers of hepatic injury and serum, urinary, and intra-erythrocyte
magnesium concentrations and dietary magnesium intake in obese children and adolescents. In a case–control study, 42 obese
children and adolescents (8–18 years) and 42 sex- and puberty-matched controls were studied. Serum, urinary, and intra-erythrocyte
magnesium levels, indices of insulin sensitivity, and liver enzymes were measured. Dietary magnesium intake was assessed using
a food frequency questionnaire. Obese children and adolescents exhibited insulin resistance as determined by a higher fasting
insulin and the HOMA-IR (p < 0.001) and lower QUICKI indices (p = 0.001); in addition these subjects had significantly higher intra-erythrocyte magnesium (IEM) concentrations, than non-obese
ones (3.99 ± 1.05 vs. 3.35 ± 1.26 mg/dL of packed cell; p = 0.015). Among liver enzymes, only gamma-glutamyl transferase (GGT) was significantly higher in obese than in non-obese
subjects (22.7 ± 9.4 vs. 17.1 ± 7.9 U/l; p = 0.002). A positive association was found between GGT and IEM in both groups; however in multivariate analysis, in obese
subjects, only GGT (p = 0.026) and, in non-obese subjects, only age (p = 0.006) remained as significant predictors of IEM. In conclusion, increased IEM concentration was seen in insulin-resistant
obese children and adolescents; furthermore, serum GGT was associated with IEM, independently of body mass index and HOMA-IR. 相似文献
26.
Maryam Ehsani Maria R. Fernández Josep A. Biosca Sylvie Dequin 《Biotechnology and bioengineering》2009,104(2):381-389
Saccharomyces cerevisiae NAD(H)‐dependent 2,3‐butanediol dehydrogenase (Bdh1), a medium chain dehydrogenase/reductase is the main enzyme catalyzing the reduction of acetoin to 2,3‐butanediol. In this work we focused on altering the coenzyme specificity of Bdh1 from NAD(H) to NADP(H). Based on homology studies and the crystal structure of the NADP(H)‐dependent yeast alcohol dehydrogenase Adh6, three adjacent residues (Glu221, Ile222, and Ala223) were predicted to be involved in the coenzyme specificity of Bdh1 and were altered by site‐directed mutagenesis. Coenzyme reversal of Bdh1 was obtained with double Glu221Ser/Ile222Arg and triple Glu221Ser/Ile222Arg/Ala223Ser mutants. The performance of the triple mutant for NADPH was close to that of native Bdh1 for NADH. The three engineered mutants were able to restore the growth of a phosphoglucose isomerase deficient strain (pgi), which cannot grow on glucose unless an alternative NADPH oxidizing system is provided, thus demonstrating their in vivo functionality. These mutants are interesting tools to reduce the excess of acetoin produced by engineered brewing or wine yeasts overproducing glycerol. In addition, they represent promising tools for the manipulation of the NADP(H) metabolism and for the development of a powerful catalyst in biotransformations requiring NADPH regeneration. Biotechnol. Bioeng. 2009; 104: 381–389 © 2009 Wiley Periodicals, Inc. 相似文献
27.
Reza Jafarzadeh-Esfehani Seyed Mostafa Parizadeh Amirsaeed Sabeti Aghabozorgi Negar Yavari Ariane Sadr-Nabavi Seyed Alireza Parizadeh Maryam Ghandehari Afsane Javanbakht Afsaneh Rezaei-Kalat Seyed Mahdi Hassanian Mohammad Vojdanparast Gordon A. Ferns Majid Khazaei Amir Avan 《Journal of cellular physiology》2020,235(10):6393-6403
Venous and arterial thrombosis are conditions that have a considerable burden if left untreated. The hypoxia-induced by the occluded vessel can disrupt the circulation of any organ, the cornerstone of treating thrombosis is rapid diagnosis and appropriate treatment. Diagnosis of thrombosis may be made by using laboratory tests or imaging techniques in individuals who have clinical manifestations of a thrombotic event. The use of serum micro ribonucleic acids (RNAs) has recently been applied to the diagnosis of thrombosis. These small RNA molecules are emerging as new diagnostic markers but have had very limited applications in vascular disease. Most of the articles provided various microRNAs with different levels of accuracy. However, there remains a lack of an appropriate panel of the most specific microRNA in the literature. The purpose of the present review was to summarize the existing data on the use of microRNAs as a diagnostic biomarker for venous thrombosis. 相似文献
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Ghoochani A Shabani K Peymani M Ghaedi K Karamali F Karbalaei K Tanhaie S Salamian A Esmaeili A Valian-Borujeni S Hashemi M Nasr-Esfahani MH Baharvand H 《Differentiation; research in biological diversity》2012,83(1):60-67
Peroxisome proliferator activated receptor γ, belongs to PPARs, which exerts various metabolic functions including differentiation process. To testify the importance of PPARγ in neural differentiation of mouse embryonic stem cells (mESCs), its expression level was assessed. Data revealed an elevation in expression level of PPARγ when neural precursors (NPs) are formed upon retinoic acid treatment. Thus, involvement of PPARγ in two stages of neural differentiation of mESCs, during and post-NPs formation was examined by application of its agonist and antagonist. Our results indicated that PPARγ inactivation via treatment with GW9662 during NPs formation, reduced expression of neural precursor and neural (neuronal and astrocytes) markers. However, PPARγ inactivation by antagonist treatment post-NPs formation stage only decreased the expression of mature astrocyte marker (Gfap) suggesting that inactivation of PPARγ by antagonist decreased astrocyte differentiation. Here, we have demonstrated the stage dependent role of PPARγ modulation on neural differentiation of mESCs by retinoic acid treatment for the first time. 相似文献
30.
Balilashaki Khosro Gantait Saikat Naderi Roohangiz Vahedi Maryam 《Physiology and Molecular Biology of Plants》2015,21(3):341-347
Physiology and Molecular Biology of Plants - We explored the influence of pollination season and maturity of capsule on post-pollination capsule formation and in vitro asymbiotic seed germination,... 相似文献