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101.
Anna U?arowska Giuseppe Dionisio Barbara Sarholz Hans-Peter Piepho Mingliang Xu Christina R?nn Ingvardsen Gerhard Wenzel Thomas Lübberstedt 《BMC plant biology》2009,9(1):15
Background
The potyviruses sugarcane mosaic virus (SCMV) and maize dwarf mosaic virus (MDMV) are major pathogens of maize worldwide. Two loci, Scmv1 and Scmv2, have ealier been shown to confer complete resistance to SCMV. Custom-made microarrays containing previously identified SCMV resistance candidate genes and resistance gene analogs were utilised to investigate and validate gene expression and expression patterns of isogenic lines under pathogen infection in order to obtain information about the molecular mechanisms involved in maize-potyvirus interactions. 相似文献102.
Yang Z Cooper PR Damera G Mukhopadhyay I Cho H Kehrl JH Panettieri RA Druey KM 《The Journal of biological chemistry》2011,286(13):11444-11455
Although short-acting and long-acting inhaled β(2)-adrenergic receptor agonists (SABA and LABA, respectively) relieve asthma symptoms, use of either agent alone without concomitant anti-inflammatory drugs (corticosteroids) may increase the risk of disease exacerbation in some patients. We found previously that pretreatment of human precision-cut lung slices (PCLS) with SABA impaired subsequent β(2)-agonist-induced bronchodilation, which occurred independently of changes in receptor quantities. Here we provide evidence that prolonged exposure of cultured human airway smooth muscle (HuASM) cells to β(2)-agonists directly augments procontractile signaling pathways elicited by several compounds including thrombin, bradykinin, and histamine. Such treatment did not increase surface receptor amounts or expression of G proteins and downstream effectors (phospholipase Cβ and myosin light chain). In contrast, β-agonists decreased expression of regulator of G protein signaling 5 (RGS5), which is an inhibitor of G-protein-coupled receptor (GPCR) activity. RGS5 knockdown in HuASM increased agonist-evoked intracellular calcium flux and myosin light chain (MLC) phosphorylation, which are prerequisites for contraction. PCLS from Rgs5(-/-) mice contracted more to carbachol than those from WT mice, indicating that RGS5 negatively regulates bronchial smooth muscle contraction. Repetitive β(2)-agonist use may not only lead to reduced bronchoprotection but also to sensitization of excitation-contraction signaling pathways as a result of reduced RGS5 expression. 相似文献
103.
In plants, reactive oxygen species (ROS) are short-lived molecules produced through various cellular mechanisms in response
to biotic and abiotic stimuli. ROS function as second messengers for hormone signaling, development, oxygen deprivation, programmed
cell death, and plant–pathogen interactions. Recent research on ROS-mediated responses has produced stimulating findings such
as the specific sources of ROS production, molecular elements that work in ROS-mediated signaling and homeostasis, and a ROS-regulated
gene network (Neill et al., Curr Opin Plant Biol 5:388–395, 2002a; Apel and Hirt, Annu Rev Plant Biol 55:373–399, 2004; Mittler et al., Trends Plant Sci 9:490–498, 2004; Mori and Schroeder, Plant Physiol 135:702–708, 2004; Kwak et al., Plant Physiol 141:323–329, 2006; Torres et al., Plant Physiol 141:373–378, 2006; Miller et al., Physiol Plant 133:481–489, 2008). In this review, we highlight new discoveries in ROS-mediated abscisic acid (ABA) signaling.
Drs. Daeshik Cho and June M. Kwak are the corresponding authors for this paper. 相似文献
104.
Aaron M. Bender Rebecca L. Weiner Vincent B. Luscombe Sonia Ajmera Hyekyung P. Cho Sichen Chang Xiaoyan Zhan Alice L. Rodriguez Colleen M. Niswender Darren W. Engers Thomas M. Bridges P. Jeffrey Conn Craig W. Lindsley 《Bioorganic & medicinal chemistry letters》2017,27(15):3576-3581
This letter describes the synthesis and structure activity relationship (SAR) studies of structurally novel M4 antagonists, based on a 3-(4-aryl/heteroarylsulfonyl)piperazin-1-yl)-6-(piperidin-1-yl)pyridazine core, identified from a high-throughput screening campaign. A multi-dimensional optimization effort enhanced potency at human M4 (hM4 IC50s < 200 nM), with only moderate species differences noted, and with enantioselective inhibition. Moreover, CNS penetration proved attractive for this series (rat brain:plasma Kp = 2.1, Kp,uu = 1.1). Despite the absence of the prototypical mAChR antagonist basic or quaternary amine moiety, this series displayed pan-muscarinic antagonist activity across M1-5 (with 9- to 16-fold functional selectivity at best). This series further expands the chemical diversity of mAChR antagonists. 相似文献
105.
Human immunodeficiency virus-specific CD8+ T-cell activity is detectable from birth in the majority of in utero-infected infants 下载免费PDF全文
Thobakgale CF Ramduth D Reddy S Mkhwanazi N de Pierres C Moodley E Mphatswe W Blanckenberg N Cengimbo A Prendergast A Tudor-Williams G Dong K Jeena P Kindra G Bobat R Coovadia H Kiepiela P Walker BD Goulder PJ 《Journal of virology》2007,81(23):12775-12784
Human immunodeficiency virus (HIV)-infected infants in sub-Saharan Africa typically progress to AIDS or death by 2 years of life in the absence of antiretroviral therapy. This rapid progression to HIV disease has been related to immaturity of the adaptive immune response in infants. We screened 740 infants born to HIV-infected mothers and tracked development and specificity of HIV-specific CD8+ T-cell responses in 63 HIV-infected infants identified using gamma interferon enzyme-linked immunospot assays and intracellular cytokine staining. Forty-four in utero-infected and 19 intrapartum-infected infants were compared to 45 chronically infected children >2 years of age. Seventy percent (14 of 20) in utero-infected infants tested within the first week of life demonstrated HIV-specific CD8+ T-cell responses. Gag, Pol, and Nef were the principally targeted regions in chronic pediatric infection. However, Env dominated the overall response in one-third (12/36) of the acutely infected infants, compared to only 2/45 (4%) of chronically infected children (P = 0.00083). Gag-specific CD4+ T-cell responses were minimal to undetectable in the first 6 months of pediatric infection. These data indicate that failure to control HIV replication in in utero-infected infants is not due to an inability to induce responses but instead suggest secondary failure of adaptive immunity in containing this infection. Moreover, the detection of virus-specific CD8+ T-cell responses in the first days of life in most in utero-infected infants is encouraging for HIV vaccine interventions in infants. 相似文献
106.
Cho Chang-Ho Shin Won-Sub Woo Do-Wook Kwon Jong-Hee 《Bioprocess and biosystems engineering》2018,41(6):803-809
Bioprocess and Biosystems Engineering - Aurantiochytrium can produce significant amounts of omega-3 fatty acids, specifically docosahexaenoic acid and docosapentaenoic acid. Use of a glucose-based... 相似文献
107.
108.
S. O. Hwang G. H. Gil Y. J. Cho K. R. Kang J. H. Lee J. C. Bae 《Applied microbiology and biotechnology》1985,22(2):108-113
Summary A process for l-phenylalanine production was studied using a tyrosine auxotrophic regulatory mutant of Escherichia coli, resistant to both -2-thienyl-dl-alanine and p-fluoro-dl-phenylalanine. Fermentations were carried out in a 30-1 fermentor with intermittent feeding of glucose plus phosphate. The mutant accumulated l-phenylalanine in the fermentation broth up to 15 g/l at pH 7.0 and 33°C. Column chromatography on a strong cation exchanger was employed as the most effective step in the purification of l-phenyl-alanine from the broth. This step brought about 4-fold concentration of the product with 96% recovery. 相似文献
109.
EST-based gene discovery in pig: virtual expression patterns and comparative mapping to human 总被引:3,自引:0,他引:3
Christopher K. Tuggle Jon A. Green Carolyn Fitzsimmons Rami Woods Randall S. Prather Sergei Malchenko Bento M. Soares Tamara Kucaba Keith Crouch Christina Smith Dylan Tack Natalie Robinson Brian O'Leary Todd Scheetz Thomas Casavant Daniel Pomp Brad J. Edeal Yuandan Zhang Max F. Rothschild Kevin Garwood William Beavis 《Mammalian genome》2003,14(8):565-579
A molecular understanding of porcine reproduction is of biological interest and economic importance. Our Midwest Consortium has produced cDNA libraries containing the majority of genes expressed in major female reproductive tissues, and we have deposited into public databases 21,499 expressed sequence tag (EST) gene sequences from the 3 end of clones from these libraries. These sequences represent 10,574 different genes, based on sequence comparison among these data, and comparison with existing porcine ESTs and genes indicate as many as 4652 of these EST clusters are novel. In silico analysis identified sequences that are expressed in specific pig tissues or organs and confirmed the broad expression in pig for many genes ubiquitously expressed in human tissues. Furthermore, we have developed computer software to identify sequence similarity of these pig genes with their human counterparts, and to extract the mapping information of these human homologues from genome databases. We demonstrate the utility of this software for comparative mapping by localizing 61 genes on the porcine physical map for Chromosomes (Chrs) 5, 10, and 14.
The following Accession numbers were assigned to our deposited sequences: BF701840 – BF704551, BF708383, BF708386 – BF713604, BG322266 – BG322271, BI398567 – BI405235, BQ597354 – BQ605166. 相似文献
110.