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201.
Rais Ahmad Khan Hamad A. Al-Lohedan Mohammad Abul Farah Mohd Sajid Ali Ali Alsalme Khalid Mashay Al-Anazi 《Journal of biomolecular structure & dynamics》2013,31(15):3905-3913
abstractThe designing of metal-based anticancer therapeutic agents can be optimized in a better and rapid way if the ligands utilized have standalone properties. Therefore, even when the organometallic/coordination complex (i.e., metallodrug) gets dissociated in extreme conditions, the ligand can endorse its biological properties. Herein, we have synthesized and characterized ?6-p-cymene ruthenium diclofenac complex. Furthermore, the ruthenium complex interactions with human serum albumin (HSA) and ct-DNA have been studied using various spectroscopic studies viz., UV, fluorescence, and circular dichroism and exhibited a significant binding propensity. Furthermore, in vitro cytotoxicity assays were carried out against human breast cancer “MCF-7” cell line. The ?6-p-cymene ruthenium diclofenac complex registered significant cytotoxicity with an IC50 value of ~25.0?µM which is comparable to the standard drugs. The ?6-p-cymene ruthenium diclofenac complex was able to decrease the MCF-7 cell proliferation and induced significant levels of apoptosis with relatively low toxicity. 相似文献
202.
Mahboobeh Zolfagharzadeh Ahmad Asoodeh Mohammad Reza Saberi 《Journal of biomolecular structure & dynamics》2013,31(12):1936-1952
This paper describes the interaction between 2,4-dinitrophenol (DNP) with the two drug carrier proteins – human serum albumin (HSA) and human holo transferrin (HTF). Hence, binding characteristics of DNP to HSA and HTF were analyzed by spectroscopic and molecular modeling techniques. Based on results obtained from fluorescence spectroscopy, DNP had a strong ability to quench the intrinsic fluorescence of HSA and HTF through a static quenching procedure. The binding constant and the number of binding sites were calculated as 2.3?×?1011?M?1 and .98 for HSA, and 1.7?×?1011?M?1 and 1.06 for HTF, respectively. In addition, synchronous fluorescence results showed that the microenvironment of Trp had a slight tendency of increasing its hydrophobicity, whereas the microenvironment of the Tyr residues of HSA did not change and that of HTF showed a significant trend (red shift of about 4?nm) of an increase in polarity. The distance between donor and acceptor was obtained by the Förster energy according to fluorescence resonance energy transfer, and was found to be 3.99 and 3.72?nm for HSA and HTF, respectively. The critical induced aggregation concentration (CCIAC) of the drug on both proteins was determined and confirmed by an inflection point of the zeta potential behavior. Circular dichroism data revealed that the presence of DNP caused a decrease of the α-helical content of HSA and HTF, and induced a remarkable mild denaturation of both proteins. The molecular modeling data confirmed our experimental results. This study is deemed useful for determining drug dosage. 相似文献
203.
Mohammad Reza Bozorgmehr Jamshidkhan Chamani Ghodsiye Moslehi 《Journal of biomolecular structure & dynamics》2013,31(8):1669-1681
Multi-spectroscopic and density functional theory (DFT) calculations was used to study the interaction between cyclophosphamide (CYP) and aspirin (ASA) with lysozyme (LYS). The experimental results showed that fluorescence quenching of LYS by drug was a result of the formation of drug–LYS complex; static quenching was confirmed to result in fluorescence quenching. Modified Stern–Volmer plots of interaction between CYP and ASA with protein in the binary and ternary systems were used to determine the binding parameters. Molecular distances between the donor (LYS) and acceptor (CYP and ASA) for all systems were estimated according to Forster’s theory. The quantitative analysis obtained by CD spectra suggested that the presence of ASA and CYP decreased the α-helical content of LYS and induced the destabilizing of it. Theoretical studies on the interaction between LYS with ASA and CYP have been carried out using DFT at the B3LYP/6-31G level in the solvent phase. Binding energy of the mentioned complexes was calculated. It showed that tryptophan (Trp) 62 had the most affinity toward ASA and CYP. Analyzing the calculated results revealed that the five member ring of Trp has a key role in interaction of LYS with ASA and CYP. 相似文献
204.
Sabra Khorsand Ahmadi Maryam Mahmoodian Moghadam Parisa Mokaberi Mohammad Reza Saberi 《Journal of biomolecular structure & dynamics》2013,31(9):1880-1898
The interaction between bovin β-Lactoglobulin (β-LG) and retinol at two different pH values was investigated by multispectroscopic, zeta potential, molecular modeling, and conductometry measurements. The steady state and polarization fluorescence spectroscopy revealed that complex formation at two different pH values could occur through a remarkable static quenching. According to fluorescence quenching, one set of binding site at pH 2 and two sets of binding sites at pH 7 were introduced for binding of retinol to β-LG that show the enhancement of saturation score of β-LG to retinol in dimmer condition. The polarization fluorescence analysis represented that there is more affinity between β-LG and retinol at pH 7 rather than at pH 2. The effect of retinol on β-LG was studied by UV-visible, circular dichroism (CD), and synchronous fluorescence, which indicated that retinol induced more structural changes on β-LG at pH 7. β-LG–retinol complex formation at two different pH values was recorded via applying resonance light scattering (RLS) and zeta potential. Conductometry and RLS showed two different behaviors of interaction between β-LG and retinol at two different pH values; therefore, dimmer formation played important roles in different behaviors of interaction between β-LG and retinol. The zeta potential was the implied combination of electrostatic and hydrophobic forces which are involved in β-LG–retinol complex at two different pH values, and the hydrophobic interactions play a dominant role in complex formation. Molecular modeling was approved by all experimental results. The acquired results suggested that monomer and dimmer states of β-LG can be induced by retinol with different behaviors. 相似文献
205.
Seyed Mahmoud Hashemi Zuhair Mohammad Hassan Ali Akbar Pourfathollah Sara Soudi Abbas Shafiee Masoud Soleimani 《Journal of cellular biochemistry》2013,114(4):955-965
Adipose tissue‐derived mesenchymal stem cells (AD‐MSCs) have been shown to be capable of differentiating into multiple cell type and exert immunomodulatory effects. Since the selection of ideal stem cell is apparently crucial for the outcome of experimental stem cell therapies, therefore, in this study we compared AD‐MSCs conditioned media (CM) from BALB/c, C57BL/6, and DBA mouse strains. No significant difference was found in the morphology, cell surface markers, in vitro differentiation and proliferation potentials of AD‐MSCs isolated from C57BL/6, BALB/c, and DBA mice. The immunological assays showed some variation among the strains in the cytokines, nitric oxide (NO), and indoleamine 2,3‐dioxygenase (IDO) production and immunomodulatory effects on splenocytes functions. Our results indicated a suppression of splenocytes proliferation in the presence of AD‐MSC CM from the three inbred mouse strains. However, BALB/c CM exerted a higher suppression of splenocytes proliferation. AD‐MSCs isolated from C57BL/6 and BALB/c mice produced higher levels of TGF‐β than those from DBA mice. Furthermore, IL‐17 and IDO production was higher in AD‐MSCs isolated from BALB/c mice. Our results indicated an increased production of TGF‐β, IL‐4, IL‐10, NO, and IDO by splenocytes in response to CM from BALB/c AD‐MSCs. In conclusion, our results showed that the immunomodulatory properties of mouse AD‐MSCs is strain‐dependent and this variation should be considered during selection of appropriate stem cell source for in vivo experiments and stem cell therapy strategies. J. Cell. Biochem. 114: 955–965, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
206.
Israt Jahan Yuriko Hirai Zahed Mohammad Malequr Rahman Md Anwarul Islam Hirohisa Hirai 《Primates; journal of primatology》2013,54(4):335-340
Hoolock gibbons (genus Hoolock) are a group of very endangered primate species that belong to the small ape family (family Hylobatidae). The entire population that is distributed in the northeast and southeast of Bangladesh is estimated to include only around 350 individuals. A conservation program is thus necessary as soon as possible. Genetic markers are significant tools for planning such programs. In this study, we examined chromosomal characteristics of two western hoolock gibbons that were captured in a Bangladesh forest. During chromosome analysis, we encountered two chromosome variations that were observed for the first time in the wild-born western hoolock gibbons (Hoolock hoolock). The first one was a nonhomologous centromere position in chromosome 8 that was observed in the two examined individuals. The alteration was identical in the two individuals, which were examined by G-band and DAPI-band analyses. Chromosome paint analyses revealed that the difference in the centromere position was due to a single small pericentric inversion. The second variation was a heterozygous elongation in chromosome 9. Analysis by sequential techniques of fluorescence in situ hybridization with 18S rDNA and silver nitrate staining revealed a single and an inverted tandem duplication, respectively, of the nucleolus organizer region in two individuals. These chromosome variations provide useful information for the next steps to consider the evolution and conservation of the hoolock gibbon. 相似文献
207.
Hossein Jafari Mansoorian Amir Hossein Mahvi Ahmad Jonidi Jafari Mohammad Mehdi Amin Ahmad Rajabizadeh Narges Khanjani 《Enzyme and microbial technology》2013,52(6-7):352-357
Electricity generation from microbial fuel cells which treat food processing wastewater was investigated in this study. Anaerobic anode and aerobic cathode chambers were separated by a proton exchange membrane in a two-compartment MFC reactor. Buffer solutions and food industry wastewater were used as electrolytes in the anode and cathode chambers, respectively. The produced voltage and current intensity were measured using a digital multimeter. Effluents from the anode compartment were tested for COD, BOD5, NH3, P, TSS, VSS, SO4 and alkalinity. The maximum current density and power production were measured 527 mA/m2 and 230 mW/m2 in the anode area, respectively, at operation organic loading (OLR) of 0.364 g COD/l.d. At OLR of 0.182 g COD/l.d, maximum voltage and columbic efficiency production were recorded 0.475 V and 21%, respectively. Maximum removal efficiency of COD, BOD5, NH3, P, TSS, VSS, SO4 and alkalinity were 86, 79, 73, 18, 68, 62, 30 and 58%, respectively. The results indicated that catalysts and mediator-less microbial fuel cells (CAML-MFC) can be considered as a better choice for simple and complete energy conversion from the wastewater of such industries and also this could be considered as a new method to offset wastewater treatment plant operating costs. 相似文献
208.
Ali Mohammadian Seyed Javad Mowla Elahe Elahi Mahmood Tavallaei Mohammad Reza Nourani Yu Liang 《Biotechnology letters》2013,35(6):843-851
Low-density quantitative real-time PCR (qPCR) arrays are often used to profile expression patterns of microRNAs in various biological milieus. To achieve accurate analysis of expression of miRNAs, non-biological sources of variation in data should be removed through precise normalization of data. We have systematically compared the performance of 19 normalization methods on different subsets of a real miRNA qPCR dataset that covers 40 human tissues. After robustly modeling the mean squared error (MSE) in normalized data, we demonstrate lower variability between replicates is achieved using various methods not applied to high-throughput miRNA qPCR data yet. Normalization methods that use splines or wavelets smoothing to estimate and remove Cq dependent non-linearity between pairs of samples best reduced the MSE of differences in Cq values of replicate samples. These methods also retained between-group variability in different subsets of the dataset. 相似文献
209.
Mohammad Javed Ansari Ahmad Al-Ghamdi Salma Usmani Rahul Kumar Adgaba Nuru Kuldeep Singh Harcharan Singh Dhaliwal 《Acta Physiologiae Plantarum》2013,35(8):2407-2419
Diploid wheat, Triticum monococcum L. (einkorn) is an ideal plant material for wheat functional genomics. Brittle culm mutant was identified by screening of the ethyl methane sulphonate-treated M 2 progenies of a T. monococcum accession pau14087 by banding the plant parts manually. The brittle culm mutant with drooping leaves, early flowering, reduced tiller numbers and susceptible to lodging had also exhibited brittleness in all plant parts than the wild-type parents. Comprehensive mechanical strength, histological, biochemical, scanning electron microscopy, and Fourier transform infrared spectroscopy analyses of brittle culm mutant supplemented and complemented the findings that the mutant had defective cellulose biosynthesis pathway and deposition of cell wall materials on secondary cell wall of mechanical tissues. Microscopic studies demonstrated that the decrease in cellulose contents resulted in the irregular cell wall organization in xylem vessels of leaf vascular bundles. To map the brc5 mutant, mapping populations were developed by crossing the brittle culm mutant with wild Triticum boeoticum acc. pau5088, having non-brittle characters. The brittle culm mutation was mapped between SSR markers, Xcfd39 and Xgwm126 on 5AmL chromosome of T. monococcum, with genetic distances of 2.6 and 4.8 cM, respectively. The brc5 mutant mapped on 5AmL, being distinct from a previously mapped brittle culm mutant in wheat, has been designated as brc5. The work on fine mapping and map-based cloning of brc5 gene regulating synthesis and deposition of cellulose on the secondary cell wall is in progress. 相似文献
210.
Elif Seyda Sarac Gözde Girgin S.Sezin Palabiyik Mohammad Charehsaz Ahmet Aydin Gönül Sahin Terken Baydar 《Biological trace element research》2013,151(3):330-334
Hot-dip galvanization is a zinc-coating process to protect the metal items from corrosion. Zinc oxide nanoaerosol fume rising from hot metal bath surface in nano dimensions contains the greatest risk for workers in galvanization process. In the present study, it was evaluated whether inhalation of zinc causes any alteration in cellular immunity and tryptophan degradation by measuring neopterin, tryptophan, kynurenine, and zinc levels in 63 male galvanization workers and 23 male office personnel as controls. Serum and urinary zinc levels were found as 14.90?±?0.90 and 102?±?4.7 μg/dL in workers while 12.87?±?1.45 and 75?±?4.2 μg/dL in controls, respectively (both, p?<?0.05). Similarly, the mean urinary neopterin levels and serum neopterin and kynurenine levels were found to be statistically higher in galvanization workers than the controls (all, p?<?0.05). Significant correlations were found between urinary neopterin levels and kynurenine to tryptophan ratio or serum zinc levels. The results indicated cellular immune activation by occupational zinc exposure. It was estimated that neopterin, in parallel with kynurenine pathway, could reflect occupational exposure to zinc nanoaerosols and might be useful in early diagnosis of immune alterations due to nano-scale exposures. 相似文献