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71.
Israel Muro Gloria Fang Kacie Gardella Indra Mahajan 《Cell cycle (Georgetown, Tex.)》2014,13(12):1918-1927
T cells devoid of tumor necrosis factor receptor associated factor-3 (Traf3) exhibit decreased proliferation, sensitivity to apoptosis, and an improper response to antigen challenge. We therefore hypothesized that TRAF3 is critical to the growth of malignant T cells. By suppressing TRAF3 protein in different cancerous T cells, we found that anaplastic large cell lymphoma (ALCL) cells require TRAF3 for proliferation. Since reducing TRAF3 results in aberrant activation of the noncanonical nuclear factor-κB (NF-κB) pathway, we prevented noncanonical NF-κB signaling by suppressing RelB together with TRAF3. This revealed that TRAF3 regulates proliferation independent of the noncanonical NF-κB pathway. However, suppression of NF-κB-inducing kinase (NIK) along with TRAF3 showed that high levels of NIK have a partial role in blocking cell cycle progression. Further investigation into the mechanism by which TRAF3 regulates cell division demonstrated that TRAF3 is essential for continued PI3K/AKT and JAK/STAT signaling. In addition, we found that while NIK is dispensable for controlling JAK/STAT activity, NIK is critical to regulating the PI3K/AKT pathway. Analysis of the phosphatase and tensin homolog (PTEN) showed that NIK modulates PI3K/AKT signaling by altering the localization of PTEN. Together our findings implicate TRAF3 as a positive regulator of the PI3K/AKT and JAK/STAT pathways and reveal a novel function for NIK in controlling PI3K/AKT activity. These results provide further insight into the role of TRAF3 and NIK in T cell malignancies and indicate that TRAF3 differentially governs the growth of B and T cell cancers. 相似文献
72.
Om Prakash Shakti Mehrotra Aneesh Krishna Bhartendu N. Mishra 《Journal of theoretical biology》2010,265(4):579-585
The present study deals with ANN based prediction of culture parameters in terms of inoculum density, pH and volume of growth medium per culture vessel and sucrose content of the growth medium for Glycyrrhiza hairy root cultures. This kind of study could be a model system in exploitation of hairy root cultures for commercial production of pharmaceutical compounds using large bioreactors. The study is aimed to evaluate the efficiency of regression neural network and back propagation neural network for the prediction of optimal culture conditions for maximum hairy root biomass yield. The training data for regression and back propagation networks were primed on the basis of function approximation, where final biomass fresh weight (fwt) was considered as a function of culture parameters. On this basis the variables in culture conditions were described in the form of equations which are for inoculum density: y=0.02x+0.04, for pH of growth medium: y=x+2.8, for sucrose content in medium: y=9.9464x+(−9.7143) and for culture medium per culture vessel: y=10x. The fresh weight values obtained from training data were considered as target values and further compared with predicted fresh weight values. The empirical data were used as testing data and further compared with values predicted from trained networks. Standard MATLAB inbuilt generalized regression network with radial basis function radbas as transfer function in layer one and purelin in layer two and back propagation having purelin as transfer function in output layer and logsig in hidden layer were used. Although in comparative assessment both the networks were found efficient for prediction of optimal culture conditions for high biomass production, more accuracy in results was seen with regression network. 相似文献
73.
Marlene Buchebner Thomas Pfeifer Nora Rathke Prakash G. Chandak Achim Lass Renate Schreiber Adelheid Kratzer Robert Zimmermann Wolfgang Sattler Harald Koefeler Eleonore Fr?hlich Gerhard M. Kostner Ruth Birner-Gruenberger Kyle P. Chiang Guenter Haemmerle Rudolf Zechner Sanja Levak-Frank Benjamin Cravatt Dagmar Kratky 《Journal of lipid research》2010,51(10):2896-2908
Cholesteryl ester (CE) accumulation in macrophages represents a crucial event during foam cell formation, a hallmark of atherogenesis. Here we investigated the role of two previously described CE hydrolases, hormone-sensitive lipase (HSL) and KIAA1363, in macrophage CE hydrolysis. HSL and KIAA1363 exhibited marked differences in their abilities to hydrolyze CE, triacylglycerol (TG), diacylglycerol (DG), and 2-acetyl monoalkylglycerol ether (AcMAGE), a precursor for biosynthesis of platelet-activating factor (PAF). HSL efficiently cleaved all four substrates, whereas KIAA1363 hydrolyzed only AcMAGE. This contradicts previous studies suggesting that KIAA1363 is a neutral CE hydrolase. Macrophages of KIAA1363−/− and wild-type mice exhibited identical neutral CE hydrolase activity, which was almost abolished in tissues and macrophages of HSL−/− mice. Conversely, AcMAGE hydrolase activity was diminished in macrophages and some tissues of KIAA1363−/− but unchanged in HSL−/− mice. CE turnover was unaffected in macrophages lacking KIAA1363 and HSL, whereas cAMP-dependent cholesterol efflux was influenced by HSL but not by KIAA1363. Despite decreased CE hydrolase activities, HSL−/− macrophages exhibited CE accumulation similar to wild-type (WT) macrophages. We conclude that additional enzymes must exist that cooperate with HSL to regulate CE levels in macrophages. KIAA1363 affects AcMAGE hydrolase activity but is of minor importance as a direct CE hydrolase in macrophages. 相似文献
74.
Data on the physico-chemical properties of proteins from soybean, groundnut, sesame seed, sunflower seed, safflower seed,
mustard seed, rapeseed and cotton seed are fairly extensive. An examination of the available data on high molecular weight
proteins suggests that there are similarities in many of their properties. In this report the similarity in amino acid composition,
size and shape, molecular weight, secondary structure, subunit composition, association-dissociation at high and low pH, stability
towards denaturants, hydrolysis by enzymes and quaternary structure of the high molecular weight proteins is discussed. Based
on these similarities a model has been proposed for the associationdissociation, denaturation and reassociation behaviour
of the high molecular weight proteins of oilseeds. 相似文献
75.
Requirement of Rad5 for DNA polymerase zeta-dependent translesion synthesis in Saccharomyces cerevisiae 下载免费PDF全文
In yeast, Rad6-Rad18-dependent lesion bypass involves translesion synthesis (TLS) by DNA polymerases eta or zeta or Rad5-dependent postreplication repair (PRR) in which error-free replication through the DNA lesion occurs by template switching. Rad5 functions in PRR via its two distinct activities-a ubiquitin ligase that promotes Mms2-Ubc13-mediated K63-linked polyubiquitination of PCNA at its lysine 164 residue and a DNA helicase that is specialized for replication fork regression. Both these activities are important for Rad5's ability to function in PRR. Here we provide evidence for the requirement of Rad5 in TLS mediated by Polzeta. Using duplex plasmids carrying different site-specific DNA lesions-an abasic site, a cis-syn TT dimer, a (6-4) TT photoproduct, or a G-AAF adduct-we show that Rad5 is needed for Polzeta-dependent TLS. Rad5 action in this role is likely to be structural, since neither the inactivation of its ubiquitin ligase activity nor the inactivation of its helicase activity impairs its role in TLS. 相似文献
76.
Observations on morphological characters of milk and permanent teeth, based on 648 pairs of dental casts of 356 male and 292 female Jat children of Haryana (India) are reported. Deciduous teeth show high frequencies of bilateral winging of maxillary central incisor, Carabelli's cusp of maxillary second molar, and deflecting wrinkle of mandibular second molar. Reduction of maxillary molar cusps is more marked in males than in females. Y pattern is very common in deciduous molars. Permanent teeth have high frequencies of grooved cingulum of incisors, cingular nodule of lateral incisors and canines, and distal accessary ridge of canines. Low frequencies of Carabelli's cusp and winging are also common. The tendency towards faintly developed shovelling in milk incisors occurs more often than in the permanent teeth. 相似文献
77.
The limited success of dendritic cell (DC)-based immunotherapy in multiple myeloma is partly due to hepatocyte growth factor (HGF)-induced DC dysfunction. From a therapeutic standpoint, it is important to understand the molecular events involved in inhibition of DC activation/maturation by HGF. Because Bruton's tyrosine kinase (Btk) negatively regulates maturation and immunostimulatory function of DCs, a role for Btk in HGF-induced inhibition of both murine and human DCs was investigated. We demonstrate that Btk is a novel proximal component of HGF-induced c-MET (HGF receptor) signaling. Following HGF treatment, Btk binds to c-MET and becomes activated. Btk activation in turn blocks the NF-κB pathway and subsequent DC activation via the c-Src-PI3K-AKT-mammalian target of rapamycin (mTOR) pathway. Notably, Btk activation is necessary for HGF-induced association of c-Src and PI3K with c-MET. Furthermore, we provide the first evidence that HGF inhibits DC activation by inducing autocrine interleukin (IL)-10 secretion, which requires activation of Btk. Blocking activation of Btk and its downstream the c-Src-PI3K-AKT-mTOR pathway prevents HGF-induced IL-10 secretion by DCs. In addition, neutralization of IL-10 secretion from DCs impaired the inhibitory effect of HGF on DCs. Thus, our study identifies a novel role for Btk in HGF-induced DC inhibition. 相似文献
78.
Venkata Sai Prakash Chaturvedula John F. Clos Joshua Rhea Dennis Milanowski Ulla Mocek Grant E. DuBois Indra Prakash 《Phytochemistry letters》2011,4(3):209-212
From the commercial extract of the leaves of Stevia rebaudiana, three new diterpenoid glycosides were isolated besides eight known steviol glycosides including stevioside, rebaudiosides A–F and dulcoside A. The structures of the three compounds were identified as 13-[(2-O-β-d-glucopyranosyl-β-d-glucopyranosyl) oxy]-kaur-16-en-18-oic acid-(6-O-β-d-xylopyranosyl-β-d-glucopyranosyl) ester (1), 13-[(2-O-β-d-glucopyranosyl-β-d-glucopyranosyl) oxy]-17-hydroxy-kaur-15-en-18-oic acid β-d-glucopyranosyl ester (2), and 13-[(2-O-β-d-glucopyranosyl-β-d-glucopyranosyl) oxy]-17-oxo-kaur-15-en-18-oic acid β-d-glucopyranosyl ester (3) on the basis of extensive NMR and MS spectral studies. Another known diterpenoid glycoside, 13-[(2-O-β-d-glucopyranosyl-β-d-glucopyranosyl) oxy]-kaur-15-en-18-oic acid β-d-glucopyranosyl ester (4) was also isolated and its complete NMR spectral assignments were made on the basis of COSY, HSQC and HMBC spectral data. 相似文献
79.
Ravikumar G Raje Urs S Vijaya Prakash NB Rao CG Vardhana KV 《Journal of invertebrate pathology》2011,107(3):193-197
We have developed a novel PCR-based assay for individual and simultaneous detection of three major pathogens (microsporidians, nucleopolyhedrovirus (NPV) and densovirus (DNV)) infecting the silkworm, Bombyx mori. Multiplex PCR, using three primer pairs, two of which were designed from the conserved regions of 16S small subunit ribosomal RNA gene of microsporidians, and polyhedrin gene of NPVs respectively, and a third primer pair designed from the internal sequences of B. mori DNVs (BmDNV), showed discrete and pathogen specific PCR products. The assay showed high specificity and sensitivity for the pathogenic DNA. Under optimized PCR conditions, the assay yielded a 794 bp DNA fragment from Nosema bombycis, 471 bp fragment from B. mori NPV (BmNPV) and 391 bp fragment from BmDNV. Further, this detection method was successfully applied to other silkworm species such as Antheraea mylitta and Samia cynthia ricini, in detecting same or similar pathogens infecting them. This method is a valuable supplement to the conventional microscopic diagnostic methods and can be used for the early detection of pathogens infecting silkworms. Furthermore it can assist research and extension centers for the safe supply of disease-free silkworms to farmers. 相似文献
80.
Prakash , U., E. S. Barghoorn , and R. A. Scott . (Harvard U., Cambridge, Mass.) Fossil wood of Robinia and Gleditsia from the Tertiary of Montana . Amer. Jour. Bot. 49(7): 692–696. Illus. 1962.—Fossil woods representing 2 genera of the Leguminosae, Robinia Linnaeus and Gleditsia Clayton, have been identified from Tertiary beds in southern Montana. These woods are noteworthy owing to their exceptionally fine structural preservation and from the standpoint of their paleogeographical distribution. Neither genus now lives in the region of Montana. 相似文献