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911.
The genetic structure of 18 populations of Lumnitzera racemosa from the Indo-West Pacific, including South China, Malay Peninsula, Sri Lanka, and North Australia, was assessed by inter simple sequence repeat (ISSR) markers. Our results showed a relatively high level of genetic variation at the species level (P = 87.04%, He = 0.260). The value of Gst was 0.642, suggesting significant genetic differentiation among populations. At the population level, however, genetic diversity was low (P = 32.17%, He = 0.097). When populations were grouped according to geographic regions, i.e., South China Sea, the East Indian Ocean, and North Australia, it was inferred from AMOVA that more than half the total variation (55.37%) was accounted for by differentiation between regions. A UPGMA dendrogram based on genetic distance also revealed a deep split between populations from these regions, indicating that Malay Peninsula and the Indonesia archipelago may play an important part on the genetic differentiation in L. racemosa. The high degree of population differentiation between regions and low genetic variation within populations recorded here highlights the need for appropriate conservation measures for this species, both in terms of incorporating further populations into protected areas, and the restoration strategies for separate regions. 相似文献
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913.
Fan Li Di Yang Yiqin Wang Baohua Liu Yijing Deng Li Wang Xiaoyun Shang Weidong Tong Bing Ni Yuzhang Wu 《Cancer immunology, immunotherapy : CII》2009,58(12):2039-2049
Ran is considered to be a promising target for tumor-specific immunotherapy because its protein is exclusively expressed in
tumor tissues, though its mRNA can be expressed in most normal tissues. In our study, we obtained four candidate wild-type
epitopes designated Ran1, Ran2, Ran3, and Ran4, derived from the Ran antigen with the highest predicted affinity with MHC-I,
indicated by affinity prediction plots and molecular dynamics simulation. However, in vitro affinity assays of these epitopes
showed only a moderate affinity with MHC-I. Thus, we designed altered peptide ligands (APLs) derived from Ran wild-type epitopes
with preferred primary and auxiliary HLA-A*0201 molecule anchor residue replacement. Of the eight tested peptides, the 1Y
analog had the strongest binding-affinity and lowest-dissociation rate to HLA-A*0201. Additionally, we investigated the CTLs
activities induced by Ran wild-type peptides and the APLs in human PBMCs and in HLA-A*0201/Kb transgenic mice. Ran1 1Y was superior to other APLs and wild-type peptides in eliciting epitope-specific CTL immune responses
both in vitro and in vivo. In summary, a wild-type epitope of the tumor-specific antigen Ran, expressed broadly in many tumors,
was identified and designated Ran1. An APL of Ran1, Ran1 1Y, was further designed and verified in vitro and in vivo and found
to elicit a stronger Ran-specific CTL response, indicating a potential anti-tumor application in the future. 相似文献
914.
Feng Qian Jing Deng Ni Cheng Emily J Welch Yongliang Zhang Asrar B Malik Richard A Flavell Chen Dong Richard D Ye 《The EMBO journal》2009,28(19):2896-2907
There are at least 11 mitogen-activated protein kinase (MAPK) phosphatases (MKPs) and only 3 major groups of MAPKs, raising the question of whether these phosphatases have non-redundant functions in vivo. Using a modified mouse model of local Shwartzman reaction, we found that deletion of the MKP5 gene, but not the MKP1 gene, led to robust and accelerated vascular inflammatory responses to a single dose of LPS injection. Depletion of neutrophils significantly reduced the vascular injury in Mkp5−/− mice, whereas adoptive transfer of Mkp5−/− neutrophils replicated the LPS-induced skin lesions in wild-type recipients. Neutrophils isolated from Mkp5−/− mice exhibited augmented p38 MAPK activation and increased superoxide generation on activation. The p38 MAPK inhibitor, SB203580, significantly reduced p47phox phosphorylation and diminished superoxide production in neutrophils. p38 MAPK phosphorylated mouse p47phox, and deletion of the p47phox gene ablated the LPS-induced vascular injury in Mkp5−/− mice. Collectively, these results show an earlier unrecognized and non-redundant function of MKP5 in restraining p38 MAPK-mediated neutrophil oxidant production, thereby preventing LPS-induced vascular injury. 相似文献
915.
Yang Bi Jiayi Huang Yun He Gao‐Hui Zhu Yuxi Su Bai‐Cheng He Jinyong Luo Yi Wang Quan Kang Qing Luo Liang Chen Guo‐Wei Zuo Wei Jiang Bo Liu Qiong Shi Min Tang Bing‐Qiang Zhang Yaguang Weng Ailong Huang Lan Zhou Tao Feng Hue H. Luu Rex C. Haydon Tong‐Chuan He Ni Tang 《Journal of cellular biochemistry》2009,108(1):295-303
Wnt/β‐catenin pathway plays an important role in regulating embryonic development. Hepatocytes differentiate from endoderm during development. Hepatic progenitor cells (HPCs) have been isolated from fetal liver and extrahepatic tissues. Most current studies in liver development and hepatic differentiation have been focused on Wnts, β‐catenin, and their receptors. Here, we sought to determine the role of Wnt antagonists in regulating hepatic differentiation of fetal liver‐derived HPCs. Using mouse liver tissues derived from embryonic day E12.5 to postnatal day (PD) 28, we found that 13 of the 19 Wnt genes and almost all of Wnt receptors/co‐receptors were expressed in most stages. However, Wnt antagonists SFRP2, SFRP3, and Dkk2 were only detected in the early stages. We established and characterized the reversible stable HPCs derived from E14.5 mouse fetal liver (HP14.5). HP14.5 cells were shown to express high levels of early liver progenitor cell markers, but low levels or none of late liver markers. HP14.5 cells were shown to differentiate into mature hepatocytes upon dexamethasone (Dex) stimulation. Dex‐induced late marker expression and albumin promoter activity in HP14.5 cells were inhibited by exogenous expression of SFRP3. Furthermore, Dex‐induced glycogen synthesis of PAS‐positive HP14.5 cells was significantly inhibited by SFRP3. Therefore, our results have demonstrated that the expression of Wnt antagonists decreases as hepatic differentiation progresses, suggesting that a balanced Wnt signaling may be critical during mouse liver development and hepatic differentiation. J. Cell. Biochem. 108: 295–303, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
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917.
918.
919.
Shaoyong Ke Fengyi Liu Ni Wang Qing Yang Xuhong Qian 《Bioorganic & medicinal chemistry letters》2009,19(2):332-335
Two series of 1,3,4-oxadiazoline heterocycle derivatives were designed, synthesized and identified. Bioactivity assays showed that all synthesized compounds inhibited chitin synthesis in yeast, suggesting they might be a novel class of potential inhibitors against chitin biosynthesis. The structure–activity relationships (SAR) of these compounds are discussed. 相似文献
920.
Jianhui Qu Shuhui Zhang Canrong Ni Hengjun Gao 《Biochemical and biophysical research communications》2009,386(3):504-509
Hepatitis B virus (HBV) may contribute to hepatocarcinogenesis by blocking p53 function. A p53 response element-like binding sequences, TGCCT?TGCCT, was found in HBV genome. To clarify whether HBV DNA can, like some other DNA viruses, bind to P53 protein and form a DNA-protein complex, we used a series of plasmids encoding full-length or mutant HBV or p53 fragments to determine the binding ability of HBV DNA after cotransfected into cells by electrophoretic mobility shift (and supershift) assay. We found that HBV DNA could bind to P53 protein and form DNA-protein complexes in human hepatoma cell lines. Cotransfection with p53 and HBV DNA increased the replication of HBV, CAT activity, tumor cell apoptosis, and cytoplasmic P53 accumulation in the hepatoma cells. In conclusions, our observations suggest that the interaction of HBV and p53 at the levels of protein-protein and DNA-protein, which resulted in inactivation of p53 transactivation. 相似文献