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1.
Mohammad-Javad Sanaei Fatemeh Taheri Masoud Heshmati Davood Bashash Roya Nazmabadi Faramarz Mohammad-Alibeigi Mahboobeh Nahid-Samiei Hedayatollah Shirzad Nader Bagheri 《Cell biology international》2021,45(10):2086-2095
Prostate cancer (PCa) is one of the most epidemic types of cancer in men. The tumor microenvironment (TME) of PCa is involved in the emergence of immunosuppressive factors such as myeloid-derived suppressor cells (MDSC), which regulate the immune system by several mechanisms, including interleukin (IL)-10 production. On the other hand, IL-17+ helper T cells (Th17) induce MDSCs and chronic inflammation in TME by producing IL-17. This study demonstrated that the frequency of CD33+ pSTAT3+ MDSC and IL-17+ lymphocyte as well as IL-10 messenger RNA (mRNA) expression were significantly higher in the PCa patients than in the benign prostatic hyperplasia (BPH) group. Moreover, there was no significant relationship between the frequency of CD33+ pSTAT3+ MDSC, and IL-17+ lymphocyte with Gleason scores in the PCa group. We suggested that the higher frequency of CD33+ pSTAT3+ MDSC and IL-17+ lymphocyte and the more frequent expression of IL-10 mRNA in PCa patients may play roles in tumor progression from BPH to PCa. 相似文献
2.
Spectrophotometric assay for horseradish peroxidase activity based on pyrocatechol-aniline coupling hydrogen donor 总被引:1,自引:0,他引:1
Molaei Rad A Ghourchian H Moosavi-Movahedi AA Hong J Nazari K 《Analytical biochemistry》2007,362(1):38-43
The hydrogen donor couples pyrocatechol-aniline and phenol-aminoantipyrine in the presence of hydrogen peroxide were compared as chromogens for horseradish peroxidase (HRP) assay. UV-Visible spectroscopy and high-performance liquid chromatography analysis indicated that during the HRP biocatalytic process, pyrocatechol-aniline was converted to a pink-colored reagent with a lambda(max) of 510 nm, which was used in the assay of HRP activity. Electrochemical studies revealed adequate electron transfer ability for this color reagent to serve as a proper mediator for HRP also. Using pyrocatechol-aniline a higher sensitivity and lower detection limit was obtained relative to those of the phenol-aminoantipyrine couple, which is commonly used for HRP assay. A relative standard deviation of 2.9% was obtained for 20 HRP activity measurements, indicating a satisfactory reproducibility for this method. In addition, kinetic parameters of K(m) (12.5mM) and V(max) (12.2 mM min(-1)mg(-1)) were calculated for pyrocatechol-aniline. Regarding the superiority of pyrocatechol-aniline, this couple is suggested to be a better hydrogen donor for the HRP spectrophotometric assay. 相似文献
3.
Karimzadeh Soureshjani Hedayatollah Nezami Ahmad Nabati Jafar Oskoueian Ehsan Ahmadi-Lahijani Mohammad Javad 《Journal of Plant Growth Regulation》2022,41(3):1109-1124
Journal of Plant Growth Regulation - Fall cultivation of field crops such as chickpea is prone to the risk of freezing stress. It is required to identify the mechanisms through which plants can... 相似文献
4.
Bakhshalizadeh S Esmaeili F Houshmand F Shirzad H Saedi M 《In vitro cellular & developmental biology. Animal》2011,47(8):550-557
Selegiline, the irreversible inhibitor of monoamine oxidase B (MAO-B), is currently used to treat Parkinson’s disease. However,
the mechanism of action of selegiline is complex and cannot be explained solely by its MAO-B inhibitory action. It stimulates
gene expression, as well as expression of a number of mRNAs or proteins in nerve and glial cells. Direct neuroprotective and
anti-apoptotic actions of selegiline have previously been observed in vitro. Previous studies showed that selegiline can induce
neuronal phenotype in cultured bone marrow stem cells and embryonic stem cells. Embryonal carcinoma (EC) cells are developmentaly
pluripotene cells which can be differentiated into all cell types under the appropriate conditions. The present study was
carried out to examine the effects of selegiline on undifferentiated P19 EC cells. The results showed that selegiline treatment
had a dramatic effect on neuronal morphology. It induced the differentiation of EC cells into neuron-like cells in a concentration-dependent
manner. The peak response was in a dose of selegiline significantly lower than required for MAO-B inhibition. The differentiated
cells were immunoreactive for neuron-specific proteins, synaptophysin, and β-III tubulin. Stem cell therapy has been considered
as an ideal option for the treatment of neurodegenerative diseases. Generation of neurons from stem cells could serve as a
source for potential cell therapy. This study suggests the potential use of combined selegiline and stem cell therapy to improve
deficits in neurodegenerative diseases. 相似文献
5.
Nanocrystalline mixed metal oxides (MMO) of various metal cations were synthesized and were used for coating a piece of copper wire as a new high sensitive solid phase micro extraction (SPME) fiber in extraction and determination of BTEX compounds from the headspace of aqueous samples prior to GC-FID analysis. Under optimum extraction conditions, the proposed fiber exhibited low detection limits, and quantification limits, good reproducibility, simple and fast preparation method, high fiber capacity and high thermal and mechanical durability. These are some of the most important advantages of the new fiber. The proposed fiber was used for human hemoglobin upon interaction with benzene. Binding isotherm, Scatchard and Klotz logarithmic plots were constructed using HS-SPME-GC data, accurately. The obtained binding isotherm analyzed using Hill method. The Hill parameters have been obtained by calculating saturation parameter from the ratio of measured chromatographic peak areas in the presence and absence of hemoglobin. In this interaction, Hill coefficient and Hill constant determined as (nH = 6.14 and log KH = 6.47) respectively. These results reveal the cooperativity of hemoglobin upon interaction with benzene. 相似文献
6.
Moosavi-Movahedi AA Chamani J Ghourchian H Shafiey H Sorenson CM Sheibani N 《Journal of Protein Chemistry》2003,22(1):23-30
The molten globule state (MG) of cytochrome c is the major intermediate of protein folding. The formation of MG state of cytochrome c is induced by n-alkyl sulfates such as sodium octyl sulfate (SOS), sodium dodecyl sulfate (SDS), and sodium tetradecyl sulfate (STS). The folding state of cytochrome c was monitored using circular dichroism (CD), isothermal titration calorimetry (ITC) and partial specific volumes. To explore a new approach for characterizing the MG conformation, cyclic voltametric studies of n-alkyl sulfates induced transition at acidic pH of cytochrome c (unfolded state, U) was carried out. Here, we have used a cystein-modified gold electrode, which is effective for direct rapid electron transfer to cytochrome c even in acid solutions, to directly observe electrochemistry in native (N) cytochrome c. Our results show that the extent of electron transfer is increased for UMG, and also the easiness of electron transferring occurred from MGN transition. Thus we demonstrate that the MG state of cytochrome c, induced by n-alkyl sulfates as salts with hydrophobic chains (hydrophobic salts), with different compactness reaches to near identical amount of electron transferring as N state. 相似文献
7.
Tavakoli H Ghourchian H Moosavi-Movahedi AA Chilaka FC 《International journal of biological macromolecules》2005,36(5):318-323
The kinetics and thermodynamics of the effects of paraoxon (POX) and ethylparathion (EPA) on choline oxidase (ChOx) were studied. Lineweaver–Burk plots of initial velocity data showed a parallel pattern indicating uncompetitive inhibition versus choline. The inhibition constant (KI) obtained from the secondary plots for POX and EPA were 0.14 ± 0.01 and 0.48 ± 0.05 mM, respectively, suggesting that POX is a more potent inhibitor of ChOx than EPA. UV absorption was used to monitor the denaturation of ChOx by POX and EPA. A decrease in FAD fluorescence associated with the interaction of POX and EPA with ChOx suggested a tertiary structural change. Interaction of the enzyme molecule with POX or EPA resulted in inhibition and subsequently denaturation of the enzyme. The results indicate that inhibition and denaturation of the enzyme by POX and EPA are linked, but not parallel events, with inhibition occurring at lower concentrations with respect to denaturation. This suggests that the loss of initial velocity of the enzyme is an active site specific effect and not due to global conformational changes induced by the inhibitors. 相似文献
8.
Hong J Moosavi-Movahedi AA Ghourchian H Amani M Amanlou M Chilaka FC 《Journal of biochemistry and molecular biology》2005,38(5):533-538
The kinetics of thermal dissociation of superoxide dismutase (SOD) was studied in 0.05 M Tris-HCl buffer at pH 7.4 containing 10(-4) M EDTA. The number of conformational locks and contact areas and amino acid residues of dimers of SOD were obtained by kinetic analysis and biochemical calculation. The cleavage bonds between dimers of SOD during thermal dissociation and type of interactions between specific amino acid residues were also simulated. Two identical contact areas between two subunits were identified. Cleavage of these contact areas resulted in dissociation of the subunits, with destruction of the active centers, and thus, lost of activity. It is suggested that the contact areas interact with active centers by conformational changes involving secondary structural elements. 相似文献
9.
Structural stabilization and functional improvement of horseradish peroxidase upon modification of accessible lysines: experiments and simulation 下载免费PDF全文
Horseradish peroxidase (HRP) is an important heme enzyme with enormous medical diagnostic, biosensing, and biotechnological applications. Thus, any improvement in the applicability and stability of the enzyme is potentially interesting. We previously reported that covalent attachment of an electron relay (anthraquinone 2-carboxylic acid) to the surface-exposed Lys residues successfully improves electron transfer properties of HRP. Here we investigated structural and functional consequences of this modification, which alters three accessible charged lysines (Lys-174, Lys-232, and Lys-241) to the hydrophobic anthraquinolysine residues. Thermal denaturation and thermoinactivation studies demonstrated that this kind of modification enhances the conformational and operational stability of HRP. The melting temperature increased 3 degrees C and the catalytic efficiency enhanced by 80%. Fluorescence and circular dichroism investigations suggest that the modified HRP benefits from enhanced aromatic packing and more buried hydrophobic patches as compared to the native one. Molecular dynamics simulations showed that modification improves the accessibility of His-42 and the heme prosthetic group to the peroxide and aromatic substrates, respectively. Additionally, the hydrophobic patch, which functions as a binding site or trap for reducing aromatic substrates, is more extended in the modified enzyme. In summary, this modification produces a new derivative of HRP with enhanced electron transfer properties, catalytic efficiency, and stability for biotechnological applications. 相似文献
10.
Sanaii Ahmad Shirzad Hedayatollah Haghighian Mehrnoosh Rahimian Ghorbanali Soltani Amin Shafigh Mohammadhadi Tahmasbi Kamran Bagheri Nader 《Molecular biology reports》2019,46(6):5703-5712
Molecular Biology Reports - Helicobacter pylori (H. pylori) has been shown to be one of the leading causes of peptic ulcer diseases (PUDs) and gastritis. T helper-22 (Th22) cells and its... 相似文献