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121.
Plants synthesize a myriad of isoprenoid products that are required both for essential constitutive processes and for adaptive responses to the environment. Two independent pathways for the biosynthesis of isoprenoid precursors coexist within the plant cell: the cytosolic mevalonic acid (MVA) pathway and the plastidial methylerythritol phosphate (MEP) pathway. In this study, we investigated the inhibitory effect of the MVA pathway on isoprenoid biosynthesized by the MEP pathway in Cannabis sativa by treatment with mevinolin. The amount of chlorophyll a, b, and total showed to be significantly enhanced in treated plants in comparison with control plants. Also, mevinolin induced the accumulation of carotenoids and α-tocopherol in treated plants. Mevinolin caused a significant decrease in tetrahydrocannabinol (THC) content. This result show that the inhibition of the MVA pathway stimulates MEP pathway but none for all metabolites. 相似文献
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123.
Ghadiry Mahdiar Ahmad Harith Hivechi Alieh Tavakoli Fatemeh Manaf Asrulnizam Abd 《Plasmonics (Norwell, Mass.)》2016,11(2):573-577
Plasmonics - Based on the influence of edge effect and channel shape, two new graphene nanoribbon field effect transistors are presented being useful in high-voltage and highly sensitive optical... 相似文献
124.
Zahra Akbari jonous Javad Shabani Shayeh Fatemeh Yazdian Amir Yadegari Mohadeseh Hashemi Meisam Omidi 《Engineering in Life Science》2019,19(3):206-216
In this paper, a most sensitive electrochemical biosensor for detection of prostate‐specific antigen (PSA) was designed. To reach the goal, a sandwich type electrode composed of reduced graphene oxide/ gold nanoparticles (GO/AuNPs), Anti‐Total PSA monoclonal antibody, and anti‐Free PSA antibody was assembled. The functionalized materials were thoroughly characterized by atomic force microscope spectroscopy, transmission electron microscopy, and X‐ray diffraction techniques. The electrochemical properties of each of the modification step were evaluated by cyclic voltammetry and electrochemical impedance spectroscopy. The results presented that the proposed biosensor possesses high sensitivity toward total and free PSA. Furthermore, the fabricated biosensor revealed an excellent selectivity for PSA in comparison to the other tumor markers such as BHCG, Alb, CEA, CA125, and CA19‐9. The limit of detection for the proposed electrochemical biosensor was estimated to be around 0.2 and 0.07 ng/mL for total and free PSA antigen, respectively. 相似文献
125.
126.
Secondary Metabolites Produced by the Marine Bacterium Halobacillus salinus That Inhibit Quorum Sensing-Controlled Phenotypes in Gram-Negative Bacteria 下载免费PDF全文
Margaret E. Teasdale Jiayuan Liu Joselynn Wallace Fatemeh Akhlaghi David C. Rowley 《Applied microbiology》2009,75(3):567-572
Certain bacteria use cell-to-cell chemical communication to coordinate community-wide phenotypic expression, including swarming motility, antibiotic biosynthesis, and biofilm production. Here we present a marine gram-positive bacterium that secretes secondary metabolites capable of quenching quorum sensing-controlled behaviors in several gram-negative reporter strains. Isolate C42, a Halobacillus salinus strain obtained from a sea grass sample, inhibits bioluminescence production by Vibrio harveyi in cocultivation experiments. With the use of bioassay-guided fractionation, two phenethylamide metabolites were identified as the active agents. The compounds additionally inhibit quorum sensing-regulated violacein biosynthesis by Chromobacterium violaceum CV026 and green fluorescent protein production by Escherichia coli JB525. Bacterial growth was unaffected at concentrations below 200 μg/ml. Evidence is presented that these nontoxic metabolites may act as antagonists of bacterial quorum sensing by competing with N-acyl homoserine lactones for receptor binding. 相似文献
127.
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
128.
Fatemeh Azarakhshi Hosein Attar Nasrin Masnabadi Hooriye Yahyaei Seiedeh Negar Mousavi 《Molecular simulation》2013,39(14):1207-1220
The generalised anomeric effect (GAE) and gauche effect (GE) associated with donor–acceptor delocalisations, dipole–dipole interactions and total steric exchange energies (TSEE) on the conformational properties of 2-methoxy- (1), 2-methylthio- (2), 2-methylseleno- (3), 2-fluoro- (4), 2-chloro- (5) and 2-bromocyclohexanone (6) have been studied by means of ab initio and hybrid density functional theory methods and natural bond orbital (NBO) analysis. All methods used showed that the axial conformation stability increased from 2-methoxy- (1) to 2-methylselenocyclohexanone (3) and also from 2-fluoro- (4) to 2-bromocyclohexanone (6), which is in agreement with reported NMR data. The results obtained by complete basis set 4 (CBS-4), B3LYP/6-311+G** and HF/6-311+G** levels for compounds 1, 5 and 6 are very similar, but the CBS-4 results for compound 4 are not in agreement with the reported experimental data (vapour phase). The NBO analysis showed that the GAE increases from compounds 1 to 3 and also from compounds 4 to 6. The low axial conformer populations of compounds 1 and 4 can be reasonably explained by their small GAE. GE does not have significant impact on the conformational behaviours of compounds 1–6 and GAE succeeds in accounting qualitatively for the increase in the axial preferences in both series of compounds. The results showed that the calculated Δ(TSEEeq–ax) values decrease from compounds 4 to 6 which contradicts the suggested arguments in the literature about these compounds. On the other hand, the calculated differences between the dipole moment values of the axial and equatorial conformations, Δ(μeq ? μax), increase from compounds 1 to 2, but decrease from compounds 2 to 3 and also decrease from compounds 4 to 6. The calculated GAE values are more significant for the explanation of the conformational preferences of compounds 1–6 than the dipole–dipole repulsion effects. The correlations between the GAE, GE, dipole–dipole interactions, Wiberg Bond Index, TSEE, donor and acceptor orbital energies and occupancies, structural parameters and conformational behaviour of compounds 1–6 have been investigated. 相似文献
129.
Abarghooi Kahaki Fatemeh Monzavi Sakineh Bamehr Hadi Bandani Eshagh Payandeh Zahra Jahangiri Abolfazl Khalili Saeed 《International journal of peptide research and therapeutics》2020,26(4):2077-2087
International Journal of Peptide Research and Therapeutics - Membrane proteins play important functions, such as cellular communication and transferring materials in the cell. Many membrane... 相似文献
130.
Ehsan Moghanloo Hasan Mollanoori Mohsen Talebi Salar Pashangzadeh Fatemeh Faraji Farimah Hadjilooei Habibollah Mahmoodzadeh 《Translational oncology》2021,14(6)
Cell-based immunotherapies have been selected for the front-line cancer treatment approaches. Among them, CAR-T cells have shown extraordinary effects in hematologic diseases including chemotherapy-resistant acute lymphoblastic leukemia (ALL), chronic lymphocytic leukemia (CLL), and non-Hodgkin lymphoma (NHL). In this approach, autologous T cells isolated from the patient''s body genetically engineered to express a tumor specific synthetic receptor against a tumor antigen, then these cells expanded ex vivo and re-infusion back to the patient body. Recently, significant clinical response and high rates of complete remission of CAR T cell therapy in B-cell malignancies led to the approval of Kymriah and Yescarta (CD19-directed CAR-T cells) were by FDA for treatment of acute lymphoblastic leukemia and diffuse large B-cell lymphoma. Despite promising therapeutic outcomes, CAR T cells also can elicit the immune-pathologic effects, such as Cytokine Release Syndrome (CRS), Tumor Lysis Syndrome (TLS), and on-target off-tumor toxicity, that hampered its application. Ineffective control of these highly potent synthetic cells causes discussed potentially life-threatening toxicities, so researchers have developed several mechanisms to remote control CAR T cells. In this paper, we briefly review the introduced toxicities of CAR-T cells, then describe currently existing control approaches and review their procedure, pros, and cons. 相似文献