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361.
B. Singh S. Sharma G. Rani V. Hallan A. A. Zaidi G. S. Virk A. Nagpal 《Plant biotechnology reports》2008,2(2):137-143
Production of Indian citrus ringspot virus (ICRSV)-free plants from an infected plant of kinnow mandarin (Citrus nobilis Lour × C. deliciosa Tenora) is reported. The shoot apices of different sizes (0.2–1.0 mm) excised from the ICRSV-infected plant were micrografted
onto decapitated rootstock seedlings of rough lemon (C. jambhiri). Micrograft survival depended on the size of shoot apex and the sucrose concentration of the culture medium. Increase in
scion size from 0.2 to 0.7 mm resulted in an increase in micrografting success rate from 30.55 to 51.88%. Further, micrograft
survival obtained with 0.2 mm was improved from 30.55 to 38.88% by increasing sucrose concentration in the culture media from
5 to 7.5%. The micrografted plants were tested for ICRSV using ELISA and RT-PCR. All plants raised from 0.2-mm scion were
found negative with both ELISA and RT-PCR whereas only 20% of the ELISA negative plants raised from 0.3-mm scion were found
negative for ICRSV with RT-PCR. The outcome of this research is the successful establishment, acclimatization and virus testing
of micrografted plants. 相似文献
362.
363.
Ashish K. Solanki Ehtesham Arif Pankaj Srivastava Christopher M. Furcht Bushra Rahman Pei Wen Avinash Singh Lawrence B. Holzman Wayne R. Fitzgibbon Milos N. Budisavljevic Glenn P. Lobo Sang-Ho Kwon Zhe Han Matthew J. Lazzara Joshua H. Lipschutz Deepak Nihalani 《The Journal of biological chemistry》2021,297(3)
Phosphorylation (activation) and dephosphorylation (deactivation) of the slit diaphragm proteins NEPHRIN and NEPH1 are critical for maintaining the kidney epithelial podocyte actin cytoskeleton and, therefore, proper glomerular filtration. However, the mechanisms underlying these events remain largely unknown. Here we show that NEPHRIN and NEPH1 are novel receptor proteins for hepatocyte growth factor (HGF) and can be phosphorylated independently of the mesenchymal epithelial transition receptor in a ligand-dependent fashion through engagement of their extracellular domains by HGF. Furthermore, we demonstrate SH2 domain–containing protein tyrosine phosphatase-2–dependent dephosphorylation of these proteins. To establish HGF as a ligand, purified baculovirus-expressed NEPHRIN and NEPH1 recombinant proteins were used in surface plasma resonance binding experiments. We report high-affinity interactions of NEPHRIN and NEPH1 with HGF, although NEPHRIN binding was 20-fold higher than that of NEPH1. In addition, using molecular modeling we constructed peptides that were used to map specific HGF-binding regions in the extracellular domains of NEPHRIN and NEPH1. Finally, using an in vitro model of cultured podocytes and an ex vivo model of Drosophila nephrocytes, as well as chemically induced injury models, we demonstrated that HGF-induced phosphorylation of NEPHRIN and NEPH1 is centrally involved in podocyte repair. Taken together, this is the first study demonstrating a receptor-based function for NEPHRIN and NEPH1. This has important biological and clinical implications for the repair of injured podocytes and the maintenance of podocyte integrity. 相似文献
364.
Patrycja Golinska Magdalena Wypij Avinash P. Ingle Indarchand Gupta Hanna Dahm Mahendra Rai 《Applied microbiology and biotechnology》2014,98(19):8083-8097
Biogenic synthesis of metal nanoparticles has been well proved by using bacteria, fungi, algae, actinomycetes, plants, etc. Among the different microorganisms used for the synthesis of metal nanoparticles, actinomycetes are less known. Although, there are reports, which have shown that actinomycetes are efficient candidates for the production of metal nanoparticles both intracellularly and extracellularly. The nanoparticles synthesized by the members of actinomycetes present good polydispersity and stability and possess significant biocidal activities against various pathogens. The present review focuses on biological synthesis of metal nanoparticles and their application in medicine. In addition, the toxicity of these biogenic metal nanoparticles to human beings and environment has also been discussed. 相似文献
365.
Bonnie Kaas Avinash R. Vaidya Amanda Leatherman Stephanie Schleidt Rebecca Eustance Kohn 《Invertebrate neuroscience : IN》2010,10(1):17-23
Mutations affecting acetylcholine receptors have been causally linked to the development of congenital myasthenic syndromes
(CMS) in humans resulting from neuromuscular transmission defects. In an undergraduate Molecular Neurobiology course, the
molecular basis of CMS was explored through study of a Caenorhabditis elegans model of the disease. The nicotinic acetylcholine receptor (nAChR), located on the postsynaptic muscle cell membrane, contains
a pentameric ring structure comprised of five homologous subunits. In the nematode C. elegans, unc-63 encodes an α subunit of nAChR. UNC-63 is required for the function of nAChR at the neuromuscular junction. Mutations in unc-63 result in defects in locomotion and egg-laying and may be used as models for CMS. Here, we describe the responses of four
unc-63 mutants to the cholinesterase inhibitor pyridostigmine bromide (range 0.9–15.6 mM in this study), a treatment for CMS that
mitigates deficiencies in cholinergic transmission by elevating synaptic ACh levels. Our results show that 15.6 mM pyridostigmine
bromide enhanced mobility in two alleles, depressed mobility in one allele and in N2, while having no effect on the fourth
allele. This indicates that while pyridostigmine bromide may be effective at ameliorating symptoms of CMS in certain cases,
it may not be a suitable treatment for all individuals due to the diverse etiology of this disease. Students in the Molecular
Neurobiology course enhanced their experience in scientific research by conducting an experiment designed to increase understanding
of genetic defects of neurological function. 相似文献
366.
367.
Avinash K. Kudva Naveen Kaushal Sonia Mohinta Mary J. Kennett Avery August Robert F. Paulson K. Sandeep Prabhu 《PloS one》2013,8(12)
Previous studies have demonstrated the ability of an eicosapentaenoic acid (EPA)-derived endogenous cyclopentenone prostaglandin (CyPG) metabolite, Δ12-PGJ3, to selectively target leukemic stem cells, but not the normal hematopoietic stems cells, in in vitro and in vivo models of chronic myelogenous leukemia (CML). Here we evaluated the stability, bioavailability, and hypersensitivity of Δ12-PGJ3. The stability of Δ12-PGJ3 was evaluated under simulated conditions using artificial gastric and intestinal juice. The bioavailability of Δ12-PGJ3 in systemic circulation was demonstrated upon intraperitoneal injection into mice by LC-MS/MS. Δ12-PGJ3 being a downstream metabolite of PGD3 was tested in vitro using primary mouse bone marrow-derived mast cells (BMMCs) and in vivo mouse models for airway hypersensitivity. ZK118182, a synthetic PG analog with potent PGD2 receptor (DP)-agonist activity and a drug candidate in current clinical trials, was used for toxicological comparison. Δ12-PGJ3 was relatively more stable in simulated gastric juice than in simulated intestinal juice that followed first-order kinetics of degradation. Intraperitoneal injection into mice revealed that Δ12-PGJ3 was bioavailable and well absorbed into systemic circulation with a Cmax of 263 µg/L at 12 h. Treatment of BMMCs with ZK118182 for 12 h resulted in increased production of histamine, while Δ12-PGJ3 did not induce degranulation in BMMCs nor increase histamine. In addition, in vivo testing for hypersensitivity in mice showed that ZK118182 induces higher airways hyperresponsiveness when compared Δ12-PGJ3 and/or PBS control. Based on the stability studies, our data indicates that intraperitoneal route of administration of Δ12-PGJ3 was favorable than oral administration to achieve effective pharmacological levels in the plasma against leukemia. Δ12-PGJ3 failed to increase histamine and IL-4 in BMMCs, which is in agreement with reduced airway hyperresponsiveness in mice. In summary, our studies suggest Δ12-PGJ3 to be a promising bioactive metabolite for further evaluation as a potential drug candidate for treating CML. 相似文献
368.
369.
The ndvA and ndvB genes of Rhizobium meliloti are involved in the export and synthesis, respectively, of the small cyclic polysaccharide beta(1,2)glucan. We have previously shown that spontaneous symbiotic pseudorevertants of ndv mutants do not produce periplasmic beta(1,2)glucan. Here we show that the pseudorevertants also do not produce extracellular beta(1,2)glucan, but do show alterations in the amount of the major acidic exopolysaccharide produced. This exopolysaccharide is not detectably different from that produced by the wild type or by the ndv mutants. A cosmid which suppresses the symbiotic defect of both ndvA and ndvB mutants was isolated from a gene bank prepared from DNA of an ndvA pseudorevertant. This cosmid contains a number of exo genes, including exoH and exoF. Subcloning and Tn5 mutagenesis were used to show that the widely separated exoH and exoF genes are both involved in suppression of the ndv mutant phenotype and that the 3.5 kb DNA fragment which contains the exoH gene does not carry the mutation responsible for second site suppression. 相似文献
370.
Numerous PEI derived polymers have been explored for their use in gene delivery. Nine PEI-chol lipopolymers based on cholesterol grafting on three polyethyleneimines (PEI) of different molecular weights have been synthesized. Firstly their aggregation behavior has been studied using transmission electron microscopy and then their interactions with l-α-dipalmitoyl phosphatidylcholine (DPPC) membranes have been examined using fluorescence anisotropy and differential scanning calorimetry (DSC). These PEI-chol lipopolymers are found to quench the chain motion of the acyl chains of DPPC, when incorporated in membranes, depending upon the cholesterol grafting on PEI. These PEI-chol lipopolymers act as filler molecules in membranes. Electron microscopy shows the different aggregation behavior of these new PEI-chol lipopolymers depending upon the molecular weight of PEI and percentage of cholesterol grafting. Detailed analysis of the fluorescence anisotropy and DSC data indicate that the nature of perturbation induced by PEI-chol lipopolymers is dependent upon the molecular weight of the PEI used and the % of cholesterol grafting on PEI. In general, PEI-chol lipopolymers rigidify the liquid-crystalline phase of the membranes without any noticeable effect on the gel phase unlike natural cholesterol, which is known to fluidize the gel phase of the membranes. 相似文献