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61.
Chandan Shee Saurabh Agarwal Deepankar Gahloth Kalpana Meena Ashwani K. Sharma 《Journal of plant biochemistry and biotechnology.》2009,18(1):101-104
A low molecular mass peptide like compound with antimicrobial and trypsin inhibitory activity was isolated from the seeds of Lagenaria siceraria. It was purified by ion-exchange and reverse-phase chromatography. The molecular weight of the compound was 678.9 Dalton as determined by MALDI-MS. The infra-red absorbance at 1639 cm?1, characteristic of an amide bond, by FTIR spectroscopic studies, and absorption at 214 nm on spectrophotometer indicates the peptidic nature of the compound. The compound exhibited antimicrobial activity when tested against Escherichia coli with minimum inhibitory concentration of 20 μM, and trypsin inhibitory activity inhibiting trypsin at a molar ratio of 1:2. 相似文献
62.
Parinita Agarwal M. K. Reddy S. K. Sopory Pradeep K. Agarwal 《Plant Molecular Biology Reporter》2009,27(4):417-430
Rab proteins form the largest family of small guanosine triphosphate (GTP)-binding proteins. The Rab family in plants is divided
into eight subfamilies, Rab1, Rab2, Rab5, Rab6, Rab7, Rab8, Rab11, and Rab18. Phylogenetic analyses of amino acid sequence
of Rab GTPases suggest their segregation into subfamilies on the basis of their localization and/or function in membrane trafficking.
The Rab GTPases are localized to the cytosolic face of specific intracellular membranes, where they function as regulators
of distinct steps in membrane-trafficking pathways. The Rab proteins show highly conserved structural features with a great
functional versatility. They play an important role in regulating hormone signaling during fruit ripening and apical dominance,
brassinosteroid biosynthesis, pollen and nodule development, and in response to both abiotic and biotic stresses. 相似文献
63.
Patricia DeInnocentes Payal Agarwal R. Curtis Bird 《Journal of cellular biochemistry》2009,106(3):491-505
Mammary cancer is among the most frequently observed canine tumors in unspayed female dogs resulting in death due to metastatic disease. These tumors are excellent models of human breast cancer but until recently there was only anecdotal evidence regarding underlying genetic defects. We recently reported expression defects in the cyclin‐dependent kinase p21/Cip1 and p53 among three independent canine mammary tumor (CMT) cell lines derived from spontaneous canine mammary cancers. We investigated further defects in the same three cell lines focusing on additional tumor suppressor gene defects in cyclin‐dependent kinase inhibitors. p27/KIP1 appeared normally expressed and did not appear to encode inactivating mutations. In contrast, expression of p16/INK4A was defective/absent in two cell lines and normal/slightly induced in the third cell line. To determine if defects were causative in maintaining the transformed phenotype, a p16/INK4A transgene was permanently transfected followed by selection and single cell cloning. CMT/p16 clones were characterized for transgene expression, p16 protein content and phenotype including proliferation rate, cell cycle phase distribution, contact inhibition, substrate dependent cell growth and cell morphology. All cell lines appeared unique yet clear indications of phenotype rescue due to p16/INK4A transgene complementation were observed suggesting that defects in p16 expression were present in all three. In some cases cellular senescence also appeared to be induced. These data provide evidence supporting p16/INK4A mutations as causative defects promoting transformation in canine mammary cancer and further characterizes tumor suppressor gene defects with functional consequences in these cells supporting their application as spontaneous animal models of human disease. J. Cell. Biochem. 106: 491–505, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
64.
Pravitt Gourh Frank C Arnett Shervin Assassi Filemon K Tan Mei Huang Laura Diekman Maureen D Mayes John D Reveille Sandeep K Agarwal 《Arthritis research & therapy》2009,11(5):R147-11
Introduction
Systemic sclerosis (SSc) (scleroderma) is a complex autoimmune disease that clinically manifests as progressive fibrosis of the skin and internal organs. Anti-centromere antibodies (ACAs), anti-topoisomerase antibodies (ATAs), and anti-RNA polymerase III antibodies (ARAs) are three mutually exclusive SSc-associated autoantibodies that correlate with distinct clinical subsets characterized by extent of cutaneous involvement and pattern of organ involvement. The current report sought to determine whether plasma cytokine profiles differ in SSc patients grouped according to these SSc-associated autoantibody subsets. 相似文献65.
Juan Miguel Lopez del Amo Vipin Agarwal Riddhiman Sarkar Justin Porter Sam Asami Martin Rübbelke Uwe Fink Yi Xue Oliver F. Lange Bernd Reif 《Journal of biomolecular NMR》2014,59(4):241-249
Relaxation parameters such as longitudinal relaxation are susceptible to artifacts such as spin diffusion, and can be affected by paramagnetic impurities as e.g. oxygen, which make a quantitative interpretation difficult. We present here the site-specific measurement of [1H]13C and [1H]15N heteronuclear rates in an immobilized protein. For methyls, a strong effect is expected due to the three-fold rotation of the methyl group. Quantification of the [1H]13C heteronuclear NOE in combination with 13C-R 1 can yield a more accurate analysis of side chain motional parameters. The observation of significant [1H]15N heteronuclear NOEs for certain backbone amides, as well as for specific asparagine/glutamine sidechain amides is consistent with MD simulations. The measurement of site-specific heteronuclear NOEs is enabled by the use of highly deuterated microcrystalline protein samples in which spin diffusion is reduced in comparison to protonated samples. 相似文献
66.
67.
Sara D. Pugh David A. MacDougall Shailesh R. Agarwal Robert D. Harvey Karen E. Porter Sarah Calaghan 《PloS one》2014,9(9)
The number of people taking statins is increasing across the globe, highlighting the importance of fully understanding statins'' effects on the cardiovascular system. The beneficial impact of statins extends well beyond regression of atherosclerosis to include direct effects on tissues of the cardiovascular system (‘pleiotropic effects’). Pleiotropic effects on the cardiac myocyte are often overlooked. Here we consider the contribution of the caveolin protein, whose expression and cellular distribution is dependent on cholesterol, to statin effects on the cardiac myocyte. Caveolin is a structural and regulatory component of caveolae, and is a key regulator of cardiac contractile function and adrenergic responsiveness. We employed an experimental model in which inhibition of myocyte HMG CoA reductase could be studied in the absence of paracrine influences from non-myocyte cells. Adult rat ventricular myocytes were treated with 10 µM simvastatin for 2 days. Simvastatin treatment reduced myocyte cholesterol, caveolin 3 and caveolar density. Negative inotropic and positive lusitropic effects (with corresponding changes in [Ca2+]i) were seen in statin-treated cells. Simvastatin significantly potentiated the inotropic response to β2-, but not β1-, adrenoceptor stimulation. Under conditions of β2-adrenoceptor stimulation, phosphorylation of phospholamban at Ser16 and troponin I at Ser23/24 was enhanced with statin treatment. Simvastatin increased NO production without significant effects on eNOS expression or phosphorylation (Ser1177), consistent with the reduced expression of caveolin 3, its constitutive inhibitor. In conclusion, statin treatment can reduce caveolin 3 expression, with functional consequences consistent with the known role of caveolae in the cardiac cell. These data are likely to be of significance, particularly during the early phases of statin treatment, and in patients with heart failure who have altered β-adrenoceptor signalling. In addition, as caveolin is ubiquitously expressed and has myriad tissue-specific functions, the impact of statin-dependent changes in caveolin is likely to have many other functional sequelae. 相似文献
68.
Pornpat Athamanolap Vishwa Parekh Stephanie I. Fraley Vatsal Agarwal Dong J. Shin Michael A. Jacobs Tza-Huei Wang Samuel Yang 《PloS one》2014,9(10)
High resolution melt (HRM) is gaining considerable popularity as a simple and robust method for genotyping sequence variants. However, accurate genotyping of an unknown sample for which a large number of possible variants may exist will require an automated HRM curve identification method capable of comparing unknowns against a large cohort of known sequence variants. Herein, we describe a new method for automated HRM curve classification based on machine learning methods and learned tolerance for reaction condition deviations. We tested this method in silico through multiple cross-validations using curves generated from 9 different simulated experimental conditions to classify 92 known serotypes of Streptococcus pneumoniae and demonstrated over 99% accuracy with 8 training curves per serotype. In vitro verification of the algorithm was tested using sequence variants of a cancer-related gene and demonstrated 100% accuracy with 3 training curves per sequence variant. The machine learning algorithm enabled reliable, scalable, and automated HRM genotyping analysis with broad potential clinical and epidemiological applications. 相似文献
69.
Shailesh R. Agarwal Pei-Chi Yang Monica Rice Cherie A. Singer Viacheslav O. Nikolaev Martin J. Lohse Colleen E. Clancy Robert D. Harvey 《PloS one》2014,9(4)
Spatially restricting cAMP production to discrete subcellular locations permits selective regulation of specific functional responses. But exactly where and how cAMP signaling is confined is not fully understood. Different receptors and adenylyl cyclase isoforms responsible for cAMP production are not uniformly distributed between lipid raft and non-lipid raft domains of the plasma membrane. We sought to determine the role that these membrane domains play in organizing cAMP responses in HEK293 cells. The freely diffusible FRET-based biosensor Epac2-camps was used to measure global cAMP responses, while versions of the probe targeted to lipid raft (Epac2-MyrPalm) and non-raft (Epac2-CAAX) domains were used to monitor local cAMP production near the plasma membrane. Disruption of lipid rafts by cholesterol depletion selectively altered cAMP responses produced by raft-associated receptors. The results indicate that receptors associated with lipid raft as well as non-lipid raft domains can contribute to global cAMP responses. In addition, basal cAMP activity was found to be significantly higher in non-raft domains. This was supported by the fact that pharmacologic inhibition of adenylyl cyclase activity reduced basal cAMP activity detected by Epac2-CAAX but not Epac2-MyrPalm or Epac2-camps. Responses detected by Epac2-CAAX were also more sensitive to direct stimulation of adenylyl cyclase activity, but less sensitive to inhibition of phosphodiesterase activity. Quantitative modeling was used to demonstrate that differences in adenylyl cyclase and phosphodiesterase activities are necessary but not sufficient to explain compartmentation of cAMP associated with different microdomains of the plasma membrane. 相似文献
70.
Ankita Agarwal Paban Kumar Dash Anil Kumar Singh Shashi Sharma Natarajan Gopalan Putcha Venkata Lakshmana Rao Man Mohan Parida Paul Reiter 《PLoS neglected tropical diseases》2014,8(7)