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331.
Shankar Sadasivan Mark Zanin Kevin O’Brien Stacey Schultz-Cherry Richard J. Smeyne 《PloS one》2015,10(4)
Although influenza is primarily a respiratory disease, it has been shown, in some cases, to induce encephalitis, including people acutely infected with the pandemic A/California/04/2009 (CA/09) H1N1 virus. Based on previous studies showing that the highly pathogenic avian influenza (HPAI) A/Vietnam/1203/2004 H5N1 virus was neurotropic, induced CNS inflammation and a transient parkinsonism, we examined the neurotropic and inflammatory potential of the CA/09 H1N1 virus in mice. Following intranasal inoculation, we found no evidence for CA/09 H1N1 virus neurotropism in the enteric, peripheral or central nervous systems. We did, however, observe a robust increase in microglial activity in the brain characterized by an increase in the number of activated Iba-1-positive microglia in the substantia nigra (SN) and the hippocampus, despite the absence of virus in the brain. qPCR analysis in SN tissue showed that the induction of microgliosis was preceded by reduced gene expression of the neurotrophic factors bdnf, and gdnf and increases in the immune modulatory chemokine chemokine (C-C motif) ligand 4 (ccl4). We also noted changes in the expression of transforming growth factor-1 (tgfβ1) in the SN starting at 7 days post-infection (dpi) that was sustained through 21 dpi, coupled with increases in arginase-1 (arg1) and csf1, M2 markers for microglia. Given that neuroinflammation contributes to generation and progression of a number of neurodegenerative disorders, these findings have significant implications as they highlight the possibility that influenza and perhaps other non-neurotropic viruses can initiate inflammatory signals via microglia activation in the brain and contribute to, but not necessarily be the primary cause of, neurodegenerative disorders. 相似文献
332.
Background
In crossbreeding programs, genomic selection offers the opportunity to make efficient use of information on crossbred (CB) individuals in the selection of purebred (PB) candidates. In such programs, reference populations often contain genotyped PB animals, although the breeding objective is usually more focused on CB performance. The question is what would be the benefit of including a larger proportion of CB individuals in the reference population.Methods
In a deterministic simulation study, we evaluated the benefit of including various proportions of CB animals in a reference population for genomic selection of PB animals in a crossbreeding program. We used a pig breeding scheme with selection for a moderately heritable trait and a size of 6000 for the reference population.Results
Applying genomic selection to improve the performance of CB individuals, with a genetic correlation between PB and CB performance (rPC) of 0.7, selection accuracy of PB candidates increased from 0.49 to 0.52 if the reference population consisted of PB individuals, it increased to 0.55 if the reference population consisted of the same number of CB individuals, and to 0.60 if the size of the CB reference population was twice that of the reference population for each PB line. The advantage of using CB rather than PB individuals increased linearly with the proportion of CB individuals in the reference population. This advantage disappeared quickly if rPC was higher or if the breeding objective put some emphasis on PB performance. The benefit of adding CB individuals to an existing PB reference population was limited for high rPC.Conclusions
Using CB rather than PB individuals in a reference population for genomic selection can provide substantial advantages, but only when correlations between PB and CB performances are not high and PB performance is not part of the breeding objective. 相似文献333.
Post ENCODE, regulatory sRNAs (rsRNAs) like miRNAs have established their status as one of the core regulatory elements of cell systems. However, large number of rsRNAs are compromised due to traditional approaches to identify miRNAs, limiting the otherwise vast world of rsRNAs mainly to hair-pin loop bred typical miRNAs. The present study has analyzed for the first time a huge volume of sequencing data from 4997 individuals and 25 cancer types to report 11 234 potentially regulatory small RNAs which appear to have deep reaching impact. The rsRNA-target interactions have been studied and validated extensively using experimental data from AGO-crosslinking, DGCR8 knockdown, CLASH, proteome and expression data. A subset of such interactions was also validated independently in the present study using multiple cell lines, by qPCR. Several of the potential rsRNAs have emerged as a critical cancer biomarker controlling some important spots of cell system. The entire study has been presented into an interactive info-analysis portal handling more than 260 GB of processed data. The possible degree of cell system regulation by sRNAs appears to be much higher than previously assumed. 相似文献
334.
This study is an attempt to gain a better understanding of the physicochemical interaction between novel anticancer drugs and DNA bases. We have employed quantum chemical tools to explore the interaction of a few anticancer drugs [namely procarbazine (PR), dacarbazine (DC) and triethylenemelamine (TR)] with isolated normal (GC and AT) and mismatch (AA, CC, GG and TT) base pairs. The molecular geometries, electronic structural stability, vibrational energies, chemical reactivity and other electronic properties were studied using MP2/6-311+G**, B3LYP/6-311+G** and M05-2X/6-311+G** methods. The optimised geometries of the usual and mismatch base pairs are almost planar whereas the geometries of drug-interacting complexes deviate from planarity. The presence of steric hindrance and π-bond overlaps between C–C bonds in the complexes has distorted the planarity of the four- and five-member rings in the base pairs. Among the three drugs chosen, DC and PR bond well with normal and mismatch base pairs with large interaction energy. The electron density (ED) difference maps of the most stable GG–DC, GG–PR and GG–TR drug-interacting complexes show the information about sharing of ED and gain or loss of ED within the interacting molecules. The stabilisation energy of the charge transfer interaction between the relevant donor–acceptor orbital of GG–DC and GC–DC complexes has been found to be around 16 kcal/mol and GG–PR and GC–PR complexes has been found to be around 12 kcal/mol. But, for the GG–TR and GC–TR complexes, the stabilisation energy is found to be less than 6 kcal/mol. Moreover, the topological analysis of hydrogen bond network of DC and PR drug-interacting complexes have high electron and Laplacian density with structural stability at the bond critical points (BCPs), while compared TR drug-interacting complexes by atoms in molecules and natural bond orbital analysis. Finally, we may conclude that the drugs DC and PR are highly efficient drugs to target normal and mismatch base pair for control and inhibition of DNA replication. 相似文献
335.
Shukkur M. Farooq Nithin B. Boppana Devarajan Asokan Shamala D. Sekaran Esaki M. Shankar Chunying Li Kaliappan Gopal Sazaly A. Bakar Harve S. Karthik Abdul S. Ebrahim 《PloS one》2014,9(4)
Oxalate toxicity is mediated through generation of reactive oxygen species (ROS) via a process that is partly dependent on mitochondrial dysfunction. Here, we investigated whether C-phycocyanin (CP) could protect against oxidative stress-mediated intracellular damage triggered by oxalate in MDCK cells. DCFDA, a fluorescence-based probe and hexanoyl-lysine adduct (HEL), an oxidative stress marker were used to investigate the effect of CP on oxalate-induced ROS production and membrane lipid peroxidation (LPO). The role of CP against oxalate-induced oxidative stress was studied by the evaluation of mitochondrial membrane potential by JC1 fluorescein staining, quantification of ATP synthesis and stress-induced MAP kinases (JNK/SAPK and ERK1/2). Our results revealed that oxalate-induced cells show markedly increased ROS levels and HEL protein expression that were significantly decreased following pre-treatment with CP. Further, JC1 staining showed that CP pre-treatment conferred significant protection from mitochondrial membrane permeability and increased ATP production in CP-treated cells than oxalate-alone-treated cells. In addition, CP treated cells significantly decreased the expression of phosphorylated JNK/SAPK and ERK1/2 as compared to oxalate-alone-treated cells. We concluded that CP could be used as a potential free radical-scavenging therapeutic strategy against oxidative stress-associated diseases including urolithiasis. 相似文献
336.
Adeline S. L. Yeo Nur Atiqah Azhar Wanyi Yeow C. Conover Talbot Jr Mohammad Asif Khan Esaki M. Shankar Anusyah Rathakrishnan Azliyati Azizan Seok Mui Wang Siew Kim Lee Mun Yik Fong Rishya Manikam Shamala Devi Sekaran 《PloS one》2014,9(4)
Objectives
Dengue represents one of the most serious life-threatening vector-borne infectious diseases that afflicts approximately 50 million people across the globe annually. Whilst symptomatic infections are frequently reported, asymptomatic dengue remains largely unnoticed. Therefore, we sought to investigate the immune correlates conferring protection to individuals that remain clinically asymptomatic.Methods
We determined the levels of neutralizing antibodies (nAbs) and gene expression profiles of host immune factors in individuals with asymptomatic infections, and whose cognate household members showed symptoms consistent to clinical dengue infection.Results
We observed broad down-regulation of host defense response (innate, adaptive and matrix metalloprotease) genes in asymptomatic individuals as against symptomatic patients, with selective up-regulation of distinct genes that have been associated with protection. Selected down-regulated genes include: TNF α (TNF), IL8, C1S, factor B (CFB), IL2, IL3, IL4, IL5, IL8, IL9, IL10 and IL13, CD80, CD28, and IL18, MMP8, MMP10, MMP12, MMP15, MMP16, and MMP24. Selected up-regulated genes include: RANTES (CCL5), MIP-1α (CCL3L1/CCL3L3), MIP-1β (CCL4L1), TGFβ (TGFB), and TIMP1.Conclusion
Our findings highlight the potential association of certain host genes conferring protection against clinical dengue. These data are valuable to better explore the mysteries behind the hitherto poorly understood immunopathogenesis of subclinical dengue infection. 相似文献337.
338.
Lei Lu Rami N. Hannoush Brian C. Goess Shankar Varadarajan Matthew D. Shair Tom Kirchhausen 《Molecular biology of the cell》2013,24(7):1020-1029
The mammalian endoplasmic reticulum (ER) is an organelle that maintains a complex, compartmentalized organization of interconnected cisternae and tubules while supporting a continuous flow of newly synthesized proteins and lipids to the Golgi apparatus. Using a phenotypic screen, we identify a small molecule, dispergo, that induces reversible loss of the ER cisternae and extensive ER tubulation, including formation of ER patches comprising densely packed tubules. Dispergo also prevents export from the ER to the Golgi apparatus, and this traffic block results in breakdown of the Golgi apparatus, primarily due to maintenance of the constitutive retrograde transport of its components to the ER. The effects of dispergo are reversible, since its removal allows recovery of the ER cisternae at the expense of the densely packed tubular ER patches. This recovery occurs together with reactivation of ER-to-Golgi traffic and regeneration of a functional Golgi with correct morphology. Because dispergo is the first small molecule that reversibly tubulates the ER and inhibits its export function, it will be useful in studying these complex processes. 相似文献
339.
Kulkarni S. Neelkant Kumar Shankar S. K. Jayalakshmi 《Preparative biochemistry & biotechnology》2013,43(9):927-934
AbstractThe present work was aimed at studying the production of lignocellulolytic enzymes, namely cellulase, xylanase, pectinase, mannanase, and laccase by a newly isolated bacterium Sphingobacterium sp. ksn-11, utilizing various agro-residues as a substrate under submerged conditions. The production of lignocellulolytic enzymes was found to be maximum at the loading of 10%(w/v) agro-residues. The enzyme secretion was enhanced by two-fold at 2?mM CaCO3, optimum pH 7, and temperature 40°. The Field Emission Gun-Scanning Electron Microscope (FEG-SEM) results have shown the degradative effect of lignocellulases; cellulase, xylanase, mannanase, pectinase, and laccase on corn husk with 3.55?U/ml, 79.22?U/ml, 12.43?U/ml, 64.66?U/ml, and 21.12?U/ml of activity, respectively. The hydrolyzed corn husk found to be good adsorbent for polyphenols released during hydrolysis of corn husk providing suitable conditions for stability of lignocellulases. Sphingobacterium sp. ksn is proved to be a promising candidate for lignocellulolytic enzymes in view of demand for enzymes in the biofuel industry. 相似文献
340.
Abhishek Dutt Tripathi Tek Raj Joshi Suresh Kumar Srivastava Kinaoush Khosravi Darani Shankar Khade Jyoti Srivastava 《Preparative biochemistry & biotechnology》2013,43(6):567-577
AbstractPolyhydroxyalkanoates (PHAs) are intracellular carbon and energy storage reserve material stored by gram-negative bacteria under nutrient limitation. PHAs are best alternative biodegradable plastics (bio-plastics) due to their resemblance to conventional synthetic plastic. The present study investigated the synergistic effect of nutritional supplements (amino acid and vitamin) on the PHA production by Alcaligenes sp. NCIM 5085 utilizing a sugar refinery waste (cane molasses) under submerged fermentation process. Initially, the effect of individual factor on PHA yield was studied by supplementing amino acids (cysteine, isoleucine, and methionine), vitamin (thiamin), and cane molasses at varying concentration in the production medium. Further, the cultivation medium was optimized by varying the levels of cane molasses, methionine and thiamin using response surface methodology to enhance the PHA yield. The maximum PHA yield of 70.89% was obtained under the optimized condition, which was then scaled up on 7.5?L-bioreactor. Batch cultivation in 7.5?L-bioreactor under the optimized condition gave a maximum PHA yield and productivity of 79.26% and 0.312 gL?1 h?1, respectively. The PHA produced was subsequently characterized as PHB by FTIR. PHB extracted was of relatively high molecular weight and crystallinity index. DSC analysis gave Tg, Tm, and Xc of 4.2, 179?°C and 66%, respectively. TGA analysis showed thermal stability with maximized degradation occurring at 302?°C, which is above the melting temperature (179?°C) of the purified polymer. The extracted polymer, therefore, possessed desirable material properties to be used in food packaging. 相似文献