排序方式: 共有311条查询结果,搜索用时 15 毫秒
1.
Omid Aryani Masoumeh Dehghan Manshadi Mahdi Tondar Elham Khalili Behnam Kamalidehghan Fatemeh Ahmadipour Somayeh Fani Massoud Houshmand 《Molecular biology reports》2014,41(9):6211-6214
Pompe disease or glycogen storage disease type II is a glycogen storage disorder associated with malfunction of the acid α-glucosidase enzyme (GAA; EC.3.2.1.3) leading to intracellular aggregations of glycogenin muscles. The infantile-onset type is the most life-threatening form of this disease, in which most of patients suffer from cardiomyopathy and hypotonia in early infancy. In this study, a typical case of Pompe disease was reported in an Iranian patient using molecular analysis of the GAA gene. Our results revealed a new c.1824_1828dupATACG mutation in exon 13 of the GAA gene. In conclusion, with the finding of this novel mutation, the genotypic spectrum of Iranian patients with Pompe disease has been extended, facilitating the definition of disease-related mutations. 相似文献
2.
Nasiripourdori A Naderi-Manesh H Ranjbar B Khajeh K 《International journal of biological macromolecules》2009,44(4):311-315
The industrial utilization of savinase is mainly constrained by its stability limitations. In the present study, the irreversible thermoinactivation of savinase has been evaluated at 70 degrees C, and various possible mechanisms for irreversible thermoinactivation of savinase were examined. The main process seemed to be autodigestion of savinase at higher temperatures. To improve the thermal stability of the enzyme, the effect of two co-solvents (sorbitol and trehalose) on the enzyme's activity and stability was investigated. Both osmolytes prevented the autolysis of savinase at 70 degrees C without inactivating the enzyme; furthermore, the structural and kinetic stabilities of the enzyme increased in the presence of additives. 相似文献
3.
Gregory E. Miller Phillip A. Engen Patrick M. Gillevet Maliha Shaikh Masoumeh Sikaroodi Christopher B. Forsyth Ece Mutlu Ali Keshavarzian 《PloS one》2016,11(2)
In the United States, there are persistent and widening socioeconomic gaps in morbidity and mortality from chronic diseases. Although most disparities research focuses on person-level socioeconomic-status, mounting evidence suggest that chronic diseases also pattern by the demographic characteristics of neighborhoods. Yet the biological mechanisms underlying these associations are poorly understood. There is increasing recognition that chronic diseases share common pathogenic features, some of which involve alterations in the composition, diversity, and functioning of the gut microbiota. This study examined whether socioeconomic-status was associated with alpha-diversity of the colonic microbiota. Forty-four healthy adults underwent un-prepped sigmoidoscopy, during which mucosal biopsies and fecal samples were collected. Subjects’ zip codes were geocoded, and census data was used to form a composite indicator of neighborhood socioeconomic-status, reflecting household income, educational attainment, employment status, and home value. In unadjusted analyses, neighborhood socioeconomic-status explained 12–18 percent of the variability in alpha-diversity of colonic microbiota. The direction of these associations was positive, meaning that as neighborhood socioeconomic-status increased, so did alpha-diversity of both the colonic sigmoid mucosa and fecal microbiota. The strength of these associations persisted when models were expanded to include covariates reflecting potential demographic (age, gender, race/ethnicity) and lifestyle (adiposity, alcohol use, smoking) confounds. In these models neighborhood socioeconomic-status continued to explain 11–22 percent of the variability in diversity indicators. Further analyses suggested these patterns reflected socioeconomic variations in evenness, but not richness, of microbial communities residing in the sigmoid. We also found indications that residence in neighborhoods of higher socioeconomic-status was associated with a greater abundance of Bacteroides and a lower abundance of Prevotella, suggesting that diet potentially underlies differences in microbiota composition. These findings suggest the presence of socioeconomic variations in colonic microbiota diversity. Future research should explore whether these variations contribute to disparities in chronic disease outcomes. 相似文献
4.
Sahar Khajeh Vahid Razban Tahereh Talaei-Khozani Masoud Soleimani Reza Asadi-Golshan Farzaneh Dehghani Amin Ramezani Zohreh Mostafavi-Pour 《Biologia》2018,73(7):715-726
High incidence of articular cartilage defects resulting from age-related degeneration or trauma injuries is a major problem worldwide. Limited self-regeneration ability of cartilage often leads to inappropriate biochemistry and structure of healed tissue. Considering Impairments of traditional treatments, cell-based therapies are promising. The rapid ex vivo expansion and chondrogenic differentiation capability make dental pulp stem cells (DPSCs) a favorable cell type for therapeutic application, however strategies in order to efficient cartilage tissue-like production are imperative. In the present study the potential role of hypoxia mimicking agent, cobalt chloride (CoCl2), on chondrogenic differentiation of human DPSCs was surveyed. Cell viability assay used to obtain the optimum dose and exposure time of CoCl2. DPSCs were differentiated in pellet culture system after CoCl2 pretreatment. Chondrogenic differentiation efficiency was evaluated by histological and immunohistological analyses. The results showed that CoCl2 led to increased pellet size, integrity and matrix deposition with organizations more resembled typical cartilage lacuna structure. Furthermore, CoCl2 could improve differentiation by elevated chondrogenic markers, glycosaminoglycans (GAGs) and collagen II expression. CoCl2 pretreatment mitigated hypertrophy, as well, which was reflected in decreased collagen X expression. Alkaline phosphatase (ALP) specific activity did not change significantly by CoCl2 preconditioning. Based on current study hypoxia mimicking agent, CoCl2, could be suggested to promote DPSCs chondrogenic differentiation. 相似文献
5.
Masoumeh Mohammadnejad;Robab Alekasir; 《Luminescence》2024,39(7):e4828
The antibiotic tetracycline can be efficiently used as medicine for the deterrence of bacterial infections in humans, animals, and plants. However, the unprecedented use of tetracycline is of great concern owing to its low biodegradability, extensive usage, and adverse impacts on the environment and water quality. In this study, a sensitive spectrofluorometric method was proposed for the direct determination of tetracycline, based on biocompatible fluorescent carbon dots (CDs). The synthesis of CDs was performed by adopting a green hydrothermal procedure from carrot juice without requiring surface passivation or outflowing any environmentally hazardous waste. X-ray diffraction analysis and transmission electron microscopy revealed amorphous spherical-shaped CDs that exhibited blue emission under blue illumination. The fabricated fluorescent probe directly detected tetracycline in the concentration range of 4.00 × 10−6 to 1.55 × 10−5 mol L−1 with an LOD of 1.33 × 10−6 mol L−1. The performance of the probe was assessed in a tap water sample, with recovery values between 80.70 and 103.60%. The method's greenness was evaluated using the Analytical Green metric approach (AGREE) and confirmed to be within the green range. The developed method is facile, rapid, cost-effective, and offers a wide linear range and satisfactory selectivity, making it potentially suitable for determining tetracycline in water applications. 相似文献
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7.
Gholivand K Alizadegan AM Firooz AA Khajeh K Naderi-Manesh H Bijanzadeh H 《Journal of enzyme inhibition and medicinal chemistry》2006,21(1):105-111
Carbacylamidophosphates with the general formula RC(O)NHP(O)R1R2 constitute organophosphorus compounds that are used as insecticides, pesticides and ureas inhibitors. In this work, we studied the inhibition potency of CCl3-C(O)NHP(O)Cl21, CHCl2C(O)NHP(O)Cl(2)2, CH2ClC(O)NHP(O)Cl23 and CF3C(O)NHP(O)Cl(2)4, which are the major intermediates for carbacylamidophosphates synthesis towards human erythrocyte acetylcholinesterase (hAChe) activity using Ellman's modified kinetic method. Unexpectedly, it was observed that they were not only hydrolytically unstable but also inhibited hAChE in a similar manner to that produced by organophosphorus insecticides. Enzymatic data, bimolecular inhibition rate constants (ki) and IC50 values for inhibition of hAChE demonstrated that they are irreversible inhibitors and the inhibition potency of compound 2 (IC50 = 88 microM) was the greatest in comparison with compounds 1, 3 and 4. Also the electropositivity of the phosphorus atom and the hydrophobicity of the compounds demonstrated that these two factors play an additional effect and different role in the inhibitory activity of these compounds. Hydrolytic stability of the compounds was determined by 31P NMR monitoring of the loss of the parent molecules with D2O as a function of time. This study considers antiacetylcholinesterase activity according to the structural and the electronic aspects of compounds 1-4, according to IR, 1H, 13C and 31P NMR spectral data. 相似文献
8.
Gholivand K Mojahed F Salehi M Naderi-Manesh H Khajeh K 《Journal of enzyme inhibition and medicinal chemistry》2006,21(5):521-525
Two novel structurally related phosphoramidate compounds, 1 and 2, with likely beta-diketone system were synthesized and characterized by 1H, 13C, 31P NMR, IR spectroscopy and elemental analysis. Compound 2 exhibited a 31P NMR signal which was significantly shielded (8 ppm) relative to compound 1. Determination of human erythrocyte acetylcholinesterase (hAChE) inhibitory activity was carried out according to Ellman's modified kinetic method and the IC50 values of compounds 1 and 2 were 1.567 and 2.986 mM, respectively. The k(i) values of 1 and 2 were 1.39 to 2.65 min(-1) respectively. A comparison of the bimolecular rate constant (k(i)) and IC50 values for the irreversible inhibitors 1 and 2 revealed that the oxono analogue has greater affinity for hAChE than the thiono compound. Furthermore effects of two conventional oximes paralidoxime (A) and obidoxime (B) on reactivation of the inhibited hAChE were studied but low reactivity was shown by both the oximes. 相似文献
9.
Shima Rajaei Saeed Karima Hessam Sepasi Tehrani Somayeh Shateri Somayeh Mahmoodi Baram Meisam Mahdavi Farzad Mokhtari Alimohammad Alimohammadi Abbas Tafakhori Abolfazl Amiri Vajiheh Aghamollaii Hamid Fatemi Masoumeh Rajabibazl Farzad Kobarfard Ali Gorji 《Journal of neurochemistry》2020,155(2):207-224
10.
A spectrophotometric method for simultaneous analysis of glycine and lysine is proposed by application of neural networks on the spectral kinetic data. The method is based on the reaction of glycine and lysine with 1,2-naphthoquinone-4-sulfonate (NQS) in slightly basic medium. On the basis of the difference in the rate between the two reactions, these two amino acids can be determined simultaneously in binary mixtures. Feed-forward neural networks have been trained to quantify considered amino acids in mixtures under optimum conditions. In this way, a one-layer network was trained. Sigmoidal and linear transfer functions were used in the hidden and output layers, respectively. Linear calibration graphs were obtained in the concentration range of 1 to 25microgml(-1) for glycine and 1 to 19microgml(-1) for lysine. The analytical performance of this method was characterized by the relative standard error. The proposed method was applied to the determination of considered amino acids in synthetic samples. 相似文献