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91.
Jim M Dunwell Mike J Wilkinson Stephen Nelson Sri Wening Andrew C Sitorus Devi Mienanti Yuzer Alfiko Adam E Croxford Caroline S Ford Brian P Forster Peter DS Caligari 《BMC plant biology》2010,10(1):1-25
Background
Studies on host-pathogen interactions in a range of pathosystems have revealed an array of mechanisms by which plants reduce the efficiency of pathogenesis. While R-gene mediated resistance confers highly effective defense responses against pathogen invasion, quantitative resistance is associated with intermediate levels of resistance that reduces disease progress. To test the hypothesis that specific loci affect distinct stages of fungal pathogenesis, a set of maize introgression lines was used for mapping and characterization of quantitative trait loci (QTL) conditioning resistance to Setosphaeria turcica, the causal agent of northern leaf blight (NLB). To better understand the nature of quantitative resistance, the identified QTL were further tested for three secondary hypotheses: (1) that disease QTL differ by host developmental stage; (2) that their performance changes across environments; and (3) that they condition broad-spectrum resistance.Results
Among a set of 82 introgression lines, seven lines were confirmed as more resistant or susceptible than B73. Two NLB QTL were validated in BC4F2 segregating populations and advanced introgression lines. These loci, designated qNLB1.02 and qNLB1.06, were investigated in detail by comparing the introgression lines with B73 for a series of macroscopic and microscopic disease components targeting different stages of NLB development. Repeated greenhouse and field trials revealed that qNLB1.06 Tx303 (the Tx303 allele at bin 1.06) reduces the efficiency of fungal penetration, while qNLB1.02 B73 (the B73 allele at bin 1.02) enhances the accumulation of callose and phenolics surrounding infection sites, reduces hyphal growth into the vascular bundle and impairs the subsequent necrotrophic colonization in the leaves. The QTL were equally effective in both juvenile and adult plants; qNLB1.06 Tx303 showed greater effectiveness in the field than in the greenhouse. In addition to NLB resistance, qNLB1.02 B73 was associated with resistance to Stewart's wilt and common rust, while qNLB1.06 Tx303 conferred resistance to Stewart's wilt. The non-specific resistance may be attributed to pleiotropy or linkage.Conclusions
Our research has led to successful identification of two reliably-expressed QTL that can potentially be utilized to protect maize from S. turcica in different environments. This approach to identifying and dissecting quantitative resistance in plants will facilitate the application of quantitative resistance in crop protection. 相似文献92.
Vaishali A. Kilor Nidhi P. Sapkal Jasmine G. Awari Bharti D. Shewale 《AAPS PharmSciTech》2010,11(1):336-343
In the present study, an attempt was made to prepare immediate-release enteric-coated pellets of aceclofenac, a poorly soluble
nonsteroidal anti-inflammatory drug that has a gastrointestinal intolerance as its serious side effect. Formulation of enteric-coated
pellets with improved solubility of aceclofenac could address both of these problems. To achieve these goals, pellets were
prepared by extrusion–spheronization method using pelletizing agents that can contribute to the faster disintegration and
thereby improve the solubility of the drug. Different disintegrants like β-cyclodextrin, kollidon CL, Ac-Di-Sol, and sodium
starch glycolate were tried in order to further improve disintegration time. The pellets were characterized for drug content,
particle size distribution, flow properties, infrared spectroscopy, surface morphology, disintegration rate, and dissolution
profile. The formulations, which showed best disintegration and dissolution profiles, were coated with Eudragit L100-55, an
enteric-coated polymer which does not dissolve at gastric pH but dissolves at intestinal pH, releasing the drug immediately
in the dissolution medium. The optimized enteric-coated formulation containing 20% κ-carrageenan, lactose, and sodium starch
glycolate as a disintegrant did inhibit the release of the drug for 2 h in 0.1 N HCl, whereas 87% of the drug was released
within 45 min. The improvement was substantial when it was compared with solubility of pure drug under the same conditions.
Thus, dissolution profiles suggested that combination of κ-carrageenan and sodium starch glycolate resulted into fast-disintegrating,
immediate-release pellets, overcoming the bioavailability problem of the poorly soluble drug, aceclofenac, and enteric coating
of these pellets avoids the exposure of aceclofenac to ulcer-prone areas of the gastrointestinal tract. 相似文献
93.
Anjana Sharma Sachin Kumar Chandraker Manisha Bharti 《Indian journal of microbiology》2007,47(3):233-240
Sixteen isolates of Nontubercular Mycobacteria species were isolated from drinking water supply of some educational institutes
in Jabalpur during July 2006 and were identified by biochemical test, thin layer chromatography (TLC) and high performance
liquid chromatography (HPLC) analysis and PRA ( PCR restriction enzyme analysis) of rpoB gene. Out of 21 water samples total
16 isolates of nontuberculous mycobacteria were identified, as M. terrae (6), M. szulgai (4), M. gordonae (3), and one each as M. malmoense, M. kansasii, and M. gastri. 相似文献
94.
In spite of the rapid advances in the development of the new proteomic technologies, there are, to date, relatively fewer studies aiming to explore the neuronal proteome. One of the reasons is the complexity of the brain, which presents high cellular heterogeneity and a unique subcellular compartmentalization. Therefore, tissue fractionation of the brain to enrich proteins of interest will reduce the complexity of the proteomics approach leading to the production of manageable and meaningful results. In this review, general considerations and strategies of proteomics, the advantages and challenges to exploring the neuronal proteome are described and summarized. In addition, this article presents an overview of recent advances of proteomic technologies and shows that proteomics can serve as a valuable tool to globally explore the changes in brain proteome during various disease states. Understanding the molecular basis of brain function will be extremely useful in identifying novel targets for the treatment of brain diseases. 相似文献
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97.
Parthasarathy NJ Srikumar R Manikandan S Narayanan GS Devi RS 《Cell biology and toxicology》2007,23(3):177-187
Our previous studies revealed that methanol intoxication significantly altered the non-specific immune functions in albino rats. The present investigation focuses on the effect of methanol on certain specific immune functions of cell mediated immunity such as footpad thickness, leukocyte migration inhibition test (LMI) and antibody levels. In addition, serum interleukins (IL-2, IL-4, TNF-alpha and IFN-gamma), and splenic lymphocyte subsets were measured after an immune challenge. The specific immune function tests were carried out in three different groups of albino rats, which include control, 15 and 30 days methanol intoxication. Our study reports that animal body weight, organ weight ratio, lymphoid cell counts, footpad thickness, antibody titer, IL-2, TNF-alpha, IFN-gamma, Pan T cell, CD4, macrophages, MHC class II molecule expression, and B cell counts were significantly decreased compared to control animals nevertheless, LMI, IL-4, and DNA single strand breakage were increased significantly. Plasma corticosterone level was significantly increased in the 15 days group whereas the 30 days methanol intoxication group showed considerable decrease in corticosterone level compared with control animals. Therefore, our investigation concluded that repeated exposure of methanol profoundly suppressed the cell mediated and humoral immune functions in albino rats. 相似文献
98.
Gehlot Ashok Chaudhary Neha Devi Jyoti Joshi Robin Kumar Dinesh Bhushan Shashi 《Plant Cell, Tissue and Organ Culture》2022,148(2):347-361
Plant Cell, Tissue and Organ Culture (PCTOC) - In vitro adventitious roots were induced from leaves of Valeriana jatamansi to assess their potential as a sustainable alternative to extract... 相似文献
99.
Jason J. Rudd Kostya Kanyuka Keywan Hassani-Pak Mark Derbyshire Ambrose Andongabo Jean Devonshire Artem Lysenko Mansoor Saqi Nalini M. Desai Stephen J. Powers Juliet Hooper Linda Ambroso Arvind Bharti Andrew Farmer Kim E. Hammond-Kosack Robert A. Dietrich Mikael Courbot 《Plant physiology》2015,167(3):1158-1185
100.