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排序方式: 共有1612条查询结果,搜索用时 15 毫秒
81.
Jun Ren Zhaohui Pei Xiyao Chen Melissa J. Berg Khalid Matrougui Qing-hua Zhang Yingmei Zhang 《生物化学与生物物理学报:疾病的分子基础》2019,1865(1):206-217
Insulin resistance leads to myocardial contractile dysfunction and deranged autophagy although the underlying mechanism or targeted therapeutic strategy is still lacking. This study was designed to examine the impact of inhibition of the cytochrome P450 2E1 (CYP2E1) enzyme on myocardial function and mitochondrial autophagy (mitophagy) in an Akt2 knockout model of insulin resistance. Adult wild-type (WT) and Akt2?/? mice were treated with the CYP2E1 inhibitor diallyl sulfide (100?mg/kg/d, i.p.) for 4?weeks. Cardiac geometry and function were assessed using echocardiographic and IonOptix systems. Western blot analysis was used to evaluate autophagy, mitophagy, inducible NOS (iNOS), and the NLRP3 inflammasome, a multi-protein intracellular pattern recognition receptor complex. Akt2 deletion triggered insulin resistance, compromised cardiac contractile and intracellular Ca2+ property, mitochondrial ultrastructural damage, elevated O2– production, as well as suppressed autophagy and mitophagy, accompanied with elevated levels of NLRP3 and iNOS, the effects of which were significantly attenuated or ablated by diallyl sulfide. In vitro studies revealed that the NLRP3 activator nigericin nullified diallyl sulfide-offered benefit against Akt2 knockout on cardiomyocyte mechanical function and mitophagy (using Western blot and colocalization of GFP-LC3 and MitoTracker Red). Moreover, inhibition of iNOS but not mitochondrial ROS production attenuated Akt2 deletion-induced activation of NLRP3, substantiating a role for iNOS-mediated NLRP3 in insulin resistance-induced changes in mitophagy and cardiac dysfunction. In conclusion, these data depict that insulin resistance through CYP2E1 may contribute to the pathogenesis of myopathic changes including myocardial contractile dysfunction, oxidative stress and mitochondrial injury, possibly through activation of iNOS and NLRP3 signaling. 相似文献
82.
Mustapha Faghire Farissi Mohamed Khadijattou Taoufiq Rachid Fghire Adnane Bargaz Btissam Mandri Khalid Oufdou Amenc Laury Jean-Jacques Drevon Cherki Ghoulam 《Symbiosis (Philadelphia, Pa.)》2013,60(3):115-122
The effect of salt stress, under glasshouse conditions, was studied on plant biomass, nodulation, and activities of acid phosphatases (APase, EC 3.1.3.2) and trehalose 6-phosphate phosphatase (TPP, EC 3.1.3.12) in the symbiosis common bean (Phaseolus vulgaris L.)-rhizobia nodules. Four common bean recombinant inbred lines (147, 115, 104 and 83) were separately inoculated, with CIAT 899 or RhM11 strains and grown in hydroaeroponic culture. Two NaCl levels (0 and 25 mM NaCl plant?1 week?1 corresponding, respectively, to the control and the salt treatment) were applied and the culture was assessed during 42 days after their transplantation. The results showed that the nodulation of these lines was not affected by salinity except for the line 83 inoculated with CIAT 899, whose nodule dry weight decreased by 48.24 % compared with the corresponding controls. For the other symbiotic combinations, shoot and root biomasses were not significantly affected by salt constraint. Salinity stress generally reduced acid phosphatise and trehalose phosphate phosphatase activities in nodules that were less affected in plants inoculated with RhM11. Based on our data, it appears that nodule phosphatase activity may be involved in salinity tolerance in common beans and the levels of salt tolerance depend principally on specific combination of the rhizobial strain and the host cultivar. 相似文献
83.
Iqbal Tahir Ijaz Mohsin Javaid Muhammad Rafique Muhammad Riaz Khalid Nadeem Tahir Muhammad Bilal Nabi Ghulam Abrar Muhammad Afsheen Sumera 《Plasmonics (Norwell, Mass.)》2019,14(1):147-154
Plasmonics - Effect of different gold (Au) grating structures on light absorption in solar cell is investigated by finite elemental analysis using COMSOL multiphysics-RF module. The geometry of the... 相似文献
84.
Cheng-Jian Zheng Xiao-Peng Lan Rui-Bin Cheng Bao-Kang Huang Ting Han Qiao-Yan Zhang Hong Zhang Khalid Rahman Lu-Ping Qin 《Phytochemistry letters》2011,4(3):298-300
A new furanofuran lignan, vitelignin A (1), together with eight known lignan derivatives, were isolated from the seeds of Vitex negundo. Their structures were identified as (+)-4-oxo-8-hydroxy-2,6-di(3,4-methylenedioxy)phenyl-3,7-dioxabicyclo[3.3.0]octane (1), 4-oxosesamin (2), (+)-sesamin (3), (+)-paulownin (4), 4-hydroxysesamin (5), 4,8-dihydroxysesamin (6), 4-oxopaulownin (7), (+)-2-(3-methoxy-4-hydroxyphenyl)-6-(3,4-methylenedioxy)phenyl-3,7-dioxabicyclo[3.3.0]octane (8), and (+)-pinoresinol (9), respectively, based on extensive NMR and MS spectroscopic studies. Compounds 1, 2, and 7 showed moderate antifungal activity in vitro. 相似文献
85.
Badr El-Sabah A. Fetoh Khalid A. Asiry 《Archives Of Phytopathology And Plant Protection》2013,46(15):1848-1856
The biochemical effects of the chlorpyrifos organophosphate insecticide and camphor plant oil in addition to their combination were studied and compared against the fourth larval instars of the cotton leaf worm Spodoptera littoralis under laboratory condition. Biochemical analysis showed that the total protein content of the cotton leaf worm larval instars was decreased at 31, 26 and 13.5% by using a camphor extract, chlorpyrifos and combination, respectively. In addition, the activity of acid phosphatase, α-esterase was significantly declined. Biochemical analysis also showed that the alkaline phosphatase activity was increased comparing with control in another side. Acetylcholinesterase enzyme amount and activity were increased with the treatment of camphor extract followed by chlorpyrifos, even though the mixture of them nearly showed the same amount in control trail. In contrast, chitinase enzyme showed a negative effect of both camphor and chlorpyrifos with nearly about the same lowering in the amount and activity of chitinase, while the mixture of them revealed a high positive increasing in the amount and activity of chitinase. On the opposite trend, phenoloxidase enzyme of treated larvae increased by action of chlorpyrifos, followed by camphor, while the mixture of them showed a negative decrease when comparing with the control. 相似文献
86.
Khan Muhammad Tahir Zeb Muhammad Tariq Ahsan Hina Ahmed Abrar Ali Arif Akhtar Khalid Malik Shaukat Iqbal Cui Zhilei Ali Sajid Khan Anwar Sheed Ahmad Manzoor Wei Dong-Qing Irfan Muhammad 《Archives of microbiology》2021,203(1):59-66
Archives of Microbiology - Severe acute respiratory syndrome virus 2 (SARS-CoV-2) belongs to the single-stranded positive-sense RNA family. The virus contains a large genome that encodes four... 相似文献
87.
Zahid H. Chohan Humayun Pervez A. Rauf Khalid M. Khan Ghulam M. Maharvi 《Journal of enzyme inhibition and medicinal chemistry》2013,28(2):161-168
A new series of antibacterial and antifungal triazine-derived mono- and di-substituted (symmetrical and unsymmetrical) Schiff-bases and their cobalt(II), copper(II), nickel(II) and zinc(II) metal complexes have been synthesized and characterized by their elemental analyses, molar conductances, magnetic moments and IR and electronic spectral measurements. IR spectra indicated the ligands to act as tridentate towards divalent metal ions via a trazine-N, the azomethine-N and, indole-NH and deprotonated-O of salicylaldehyde. The magnetic moments and electronic spectral data suggest octahedral geometry for the Co(II), Ni(II) and Zn(II)complexes and square-pyramid for Cu(II) complexes. NMR spectral data of the ligands and their diamagnetic zinc(II) complexes well-define their proposed structures/geometries. Elemental analyses data of the ligands and metal complexes agree with their proposed structures/geometries. The synthesized ligands, along with their metal complexes were screened for their antibacterial activity against Escherichia coli, Bacillus subtillis, Shigella flexneri, Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella typhi and for antifungal activity against Trichophyton longifusus, Candida albicans, Aspergillus flavus, Microsporum canis, Fusarium solani and Candida glaberata. The results of these studies show the metal complexes to be more antibacterial/antifungal against two or more species as compared to the uncomplexed Schiff-base ligands. 相似文献
88.
Hiranmoy Das Zhihui Wang M. Khalid Khan Niazi Reeva Aggarwal Jingwei Lu Suman Kanji Manjusri Das Matthew Joseph Metin Gurcan Vittorio Cristini 《PloS one》2013,8(4)
Molecular-focused cancer therapies, e.g., molecularly targeted therapy and immunotherapy, so far demonstrate only limited efficacy in cancer patients. We hypothesize that underestimating the role of biophysical factors that impact the delivery of drugs or cytotoxic cells to the target sites (for associated preferential cytotoxicity or cell signaling modulation) may be responsible for the poor clinical outcome. Therefore, instead of focusing exclusively on the investigation of molecular mechanisms in cancer cells, convection-diffusion of cytotoxic molecules and migration of cancer-killing cells within tumor tissue should be taken into account to improve therapeutic effectiveness. To test this hypothesis, we have developed a mathematical model of the interstitial diffusion and uptake of small cytotoxic molecules secreted by T-cells, which is capable of predicting breast cancer growth inhibition as measured both in vitro and in vivo. Our analysis shows that diffusion barriers of cytotoxic molecules conspire with γδ T-cell scarcity in tissue to limit the inhibitory effects of γδ T-cells on cancer cells. This may increase the necessary ratios of γδ T-cells to cancer cells within tissue to unrealistic values for having an intended therapeutic effect, and decrease the effectiveness of the immunotherapeutic treatment. 相似文献
89.
Jamal M. Khaled Sami A. Alyahya C. Chenthis Kanisha Naiyf S. Alharbi Shine Kadaikunnan G. Ramachandran Khalid F. Alanzi G. Rajivgandhi RTV Vimala N. Manoharan 《Saudi Journal of Biological Sciences》2021,28(1):302-309
Urinary tract infections are second most important diseases worldwide due to the increased amount of antibiotic resistant microbes. Among the Gram negative bacteria, P. mirabilis is the dominant biofilm producer in urinary tract infections next to E. coli. Biofilm is a process that produced self-matrix of more virulence pathogens on colloidal surfaces. Based on the above fact, this study was concentrated to inhibit the P. mirabilis biofilm formation by various in-vitro experiments. In the current study, the anti-biofilm effect of essential oils was recovered from the medicinal plant of Solanum nigrum, and confirmed the available essential oils by liquid chromatography-mass spectroscopy analysis. The excellent anti-microbial activity and minimum biofilm inhibition concentration of the essential oils against P. mirabilis was indicated at 200 µg/mL. The absence of viability and altered exopolysaccharide structure of treated cells were showed by biofilm metabolic assay and phenol–sulphuric acid method. The fluorescence differentiation of P. mirabilis treated cells was showed with more damages by confocal laser scanning electron microscope. Further, more morphological changes of essential oils treated cells were differentiated from normal cells by scanning electron microscope. Altogether, the results were reported that the S. nigrum essential oils have anti-biofilm ability. 相似文献
90.
Spectrometric studies on stability of tenuazonic acid (TeA) solution in organic solvents 总被引:1,自引:0,他引:1
The stability of tenuazonic acid solution at different temperatures and storage times was studied using methanol, methanol-water
(8:2 v/v), benzene and benzene-acetonitrile (98:2 v/v) as solvents. Solutions were analysed by a spectrometric method TeA
U.V.-spectrum was recorded. Results indicated that the optimum temperature for long-time storage period of tenuazonic acid
solution in any solvent assayed is -20°C. Benzene and benzene-acetonitrile (98:2 v/v) could be advised to make tenuazonic
acid solution which will be stored less than 2 months at 4°C. Methanol and methanolwater (8:2 v/v) are not recommended because
a low stability of TeA solution in this solvents. 相似文献