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211.
Homer RJ Zheng T Chupp G He S Zhu Z Chen Q Ma B Hite RD Gobran LI Rooney SA Elias JA 《American journal of physiology. Lung cellular and molecular physiology》2002,283(1):L52-L59
Interleukin (IL)-13, a key mediator of Th2-mediated immunity, contributes to the pathogenesis of asthma and other pulmonary diseases via its ability to generate fibrosis, mucus metaplasia, eosinophilic inflammation, and airway hyperresponsiveness. In these studies, we compared surfactant accumulation in wild-type mice and mice in which IL-13 was overexpressed in the lung. When compared with littermate controls, transgenic animals showed alveolar type II cell hypertrophy under light and electron microscopy. Over time, their alveoli also filled with surfactant in a pulmonary alveolar proteinosis pattern. At the same time, prominent interstitial fibrosis occurs. Bronchoalveolar lavage fluid from these mice had a three- to sixfold increase in surfactant phospholipids. Surfactant proteins (SP)-A, -B, and -C showed two- to threefold increases, whereas SP-D increased 70-fold. These results indicate that IL-13 is a potent stimulator of surfactant phospholipid and surfactant accumulation in the lung. IL-13 may therefore play a central role in the broad range of chronic pulmonary conditions in which fibrosis, type II cell hypertrophy, and surfactant accumulation occur. 相似文献
212.
213.
Construction of a high density integrated genetic map for cucumber (Cucumis sativus L.) 总被引:1,自引:0,他引:1
Zhang WW Pan JS He HL Zhang C Li Z Zhao JL Yuan XJ Zhu LH Huang SW Cai R 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2012,124(2):249-259
The high-density consensus map was constructed based on the GY14 × PI 183967 map from an inter-subspecific cross and the extended
S94 × S06 map from an intra-subspecific cross. The consensus map was composed of 1,369 loci, including 1,152 SSR loci, 192
SRAP loci, 21 SCAR loci and one STS locus as well as three gene loci of fruit external quality traits in seven chromosomes,
and spanned 700.5 cM, of which 682.7 cM (97.5%) were covered by SSR markers. The average genetic distance and physical interval
between loci were 0.51 cM and ~268 kbp, respectively. Additionally, the physical position of the sequence-associated markers
aligned along the assembled cucumber genome sequence established a relationship between genetic maps and cucumber genome sequence
and to a great extent validated the order of markers in individual maps and consensus map. This consensus map with a high
marker density and well-ordered markers is a saturated and reliable linkage map for genetic analysis of cucumber or the Cucurbitaceae
family of plants. 相似文献
214.
215.
Metabolic control analysis is helpful for informed genetic manipulation of oilseed rape (Brassica napus) to increase seed oil content 总被引:4,自引:0,他引:4
Weselake RJ Shah S Tang M Quant PA Snyder CL Furukawa-Stoffer TL Zhu W Taylor DC Zou J Kumar A Hall L Laroche A Rakow G Raney P Moloney MM Harwood JL 《Journal of experimental botany》2008,59(13):3543-3549
Top-down control analysis (TDCA) is a useful tool for quantifying constraints on metabolic pathways that might be overcome by biotechnological approaches. Previous studies on lipid accumulation in oilseed rape have suggested that diacylglycerol acyltransferase (DGAT), which catalyses the final step in seed oil biosynthesis, might be an effective target for enhancing seed oil content. Here, increased seed oil content, increased DGAT activity, and reduced substrate:product ratio are demonstrated, as well as reduced flux control by complex lipid assembly, as determined by TDCA in Brassica napus (canola) lines which overexpress the gene encoding type-1 DGAT. Lines overexpressing DGAT1 also exhibited considerably enhanced seed oil content under drought conditions. These results support the use of TDCA in guiding the rational selection of molecular targets for oilseed modification. The most effective lines had a seed oil increase of 14%. Moreover, overexpression of DGAT1 under drought conditions reduced this environmental penalty on seed oil content. 相似文献
216.
Sun W Xing B Sun Y Du X Lu M Hao C Lu Z Mi W Wu S Wei H Gao X Zhu Y Jiang Y Qian X He F 《Molecular & cellular proteomics : MCP》2007,6(10):1798-1808
Hepatocellular carcinoma (HCC) is a highly malignant tumor, and chronic infection with hepatitis B virus is one of its major risk factors. To identify the proteins involved in HCC carcinogenesis, we used two-dimensional fluorescence DIGE to study the differentially expressed proteins in tumor and adjacent nontumor tissue samples. Samples from 12 hepatitis B virus-associated HCC patients were analyzed. A total of 61 spots were significantly up-regulated (ratio >/= 2, p = 0.01) in tumor samples, whereas 158 spots were down-regulated (ratio = -2, p = 0.01). Seventy-one gene products were identified among these spots. Members of the heat shock protein 70 and 90 families were simultaneously up-regulated, whereas metabolism-associated proteins were decreased in HCC samples. The down-regulation of mitochondrial and peroxisomal proteins in these results suggested loss of special organelle functions during HCC carcinogenesis. Four metabolic enzymes involved in the methylation cycle in the liver were down-regulated in HCC tissues, indicating S-adenosylmethionine deficiency in HCC. Two gene products, glyceraldehyde-3-phosphate dehydrogenase and formimidoyltransferase-cyclodeaminase, were identified from inversely altered spots, suggesting that different isoforms or post-translational modifications of these two proteins might play different roles in HCC. For the first time, the overexpression of Hcp70/Hsp90-organizing protein and heterogeneous nuclear ribonucleoproteins C1/C2 in HCC tissues was confirmed by Western blot and then by immunohistochemistry staining in 70 HCC samples, suggesting their potential as protein tumor markers. In summary, we profiled proteome alterations in HCC tissues, and these results may provide useful insights for understanding the mechanism involved in the process of HCC carcinogenesis. 相似文献
217.
The complete mitochondrial genome (mitogenome) of Actias selene (Lepidoptera: Saturniidae) was determined to be 15,236 bp, including 13 protein-coding genes (PCGs), two rRNA genes, 22 tRNA genes and a control region. The arrangement of 13 PCGs was similar to that of other sequenced lepidopterans. The AT skew of the mitogenome of A. selene was slightly negative, indicating a higher number of T compared to A nucleotides. The nucleotide composition of the mitogenome of A. selene was also biased toward A+T nucleotides (78.91%). All PCGs were initiated by ATN codons, except for the gene encoding cytochrome c oxidase subunit 1 (cox1), which may be initiated by the TTAG, as observed in other lepidopterans. Three genes, including cox1, cox2, and nad5, had incomplete stop codons consisting of just a T. With an exception for trnS1(AGN), all the other tRNA genes displayed a typical clover-leaf structure of mitochondrial tRNA. The A+T-rich region of the mitogenome of A. selene was 339 bp in length, and contains several features common to the Lepidopteras, including non-repetitive sequences, a conserved structure combining the motif ATAGA and an 18-bp poly-T stretch and a poly-A element upstream of trnM gene. Phylogenetic analysis showed that A. selene was close to Saturniidae. 相似文献
218.
大棚网纹甜瓜品种主要经济性状模糊综合评判 总被引:2,自引:0,他引:2
本文根据模糊数学的基本原理,对大棚栽培的13个网纹甜瓜品种,采用品质、产量和成熟期等11个经济性状,进行模糊综合评判.结果表明:Andes和Volga的综合经济性状较好;Earl’sSeine夏系I、Marchen、秋绿、Earl’s东海PF80,Heim,Earl’sSeine夏系Ⅱ、夏绿和Kyanaru次之;Bolero,JohnnyEarl’s和Earl’s东海S78较差.作者认为:Andes及Volga为大棚栽培的首选品种,其次选用Earl’sSeine夏系I、秋绿和Earl’s东海PF80等品种. 相似文献
219.
Liu Siqi Wang Bo Li Xiaojing Pan Jingxian Qian Xuexue Yu Yahui Xu Ping Zhu Jian Xu Xiaofeng 《Plant Cell, Tissue and Organ Culture》2019,137(3):485-494
Plant Cell, Tissue and Organ Culture (PCTOC) - Callus is a remarkable regeneration tissue. The genes correlated with root development can be involved in regulating callus development in higher... 相似文献
220.
We determined whether salicylate at pharmacological concentrations inhibits nitric-oxide synthase-2 (NOS-2) and cyclo-oxygenase-2 (COX-2) expressions in RAW 264.7 stimulated with lipopolysaccharide (LPS) and interferon-gamma (IFN-gamma). Cells were treated with sodium salicylate (10(-7)-10(-4) m) or vehicle for 30 min followed by LPS+IFN-gamma for up to 24 h. Salicylate suppressed NOS-2 and COX-2 protein levels and promoter activities stimulated by LPS+IFN-gamma for 4 h in a concentration-dependent manner but had no effect on NOS-2 expression stimulated by the combined agonists for 24 h. Results from promoter analysis indicate that the binding of CCAAT/enhancer-binding protein beta (C/EBPbeta) to its cognate site at -150/-142 on the NOS-2 promoter region was essential for NOS-2 expression at 4 h but not at 24 h. Salicylate reduced C/EBPbeta binding at 4 h and did not alter its binding at 24 h. NOS-2 and COX-2 protein levels and C/EBPbeta binding stimulated by LPS+IFN-gamma for 4 h were inhibited by a similar battery of signaling inhibitors, suggesting a common pathway for NOS-2 and COX-2 expression. Kinetic analysis indicates that NOS-2, similar to COX-2 expression, at 4 h was largely due to the action of LPS, which induced C/EBPbeta binding, whereas its expression at a longer time point was contributed by IFN-gamma. Our findings implicate two distinct pathways for NOS-2 expression induced by LPS+IFN-gamma. Salicylate at pharmacological concentrations is capable of suppressing the early phase of NOS-2 and COX-2 expression by blocking C/EBPbeta binding. 相似文献