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101.
This paper assesses the extent of success and failure of mangrove plantations in Myanmar, restored by local people with the help of foresters under a community forestry program initiated in 1995. The species of these restored plantations are Avicennia officinalis, Avicennia marina and Heritiera fomes, each of which was restored on two plots, one on low and one on high ground, yielding a total of six plots. These plots have been continuously monitored in order to investigate survival and growth rates. The plots were established on abandoned land that had been previously used for paddy cultivation. Cyclone Nargis hit these plantations during the monitoring period, at the beginning of May, 2008. As a consequence, the survival rates of A. officinalis on low ground and A. marina on high ground declined slightly, but the overall affect was not severe. Excluding individuals affected by the cyclone, height and diameter growth of A. officinalis and A. marina were significantly higher on low ground than on high ground, i.e. on sites thought to be consistently similar to the natural habitats of these species. Contrary to these two Avicennia species, the height growth of H. fomes was higher on high ground than on low ground; the diameter growth was not significantly different. As the growth of H. fomes was very slow, however, it is still not possible to describe the differences clearly. This study may provide useful guidelines for foresters and local people to establish successful mangrove restorations and to predict production from community-owned mangrove forests.  相似文献   
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In our previous paper, we reported that rosmarinic acid (1) of Argusia argentea could neutralize snake venom induced hemorrhagic action. Rosmarinic acid (1) consists of two phenylpropanoids: caffeic acid (2) and 3-(3,4-dihydroxyphenyl)lactic acid (3). In this study, we investigated the structural requirements necessary for inhibition of snake venom activity through the use of compounds, which are structurally related to rosmarinic acid (1). By examining anti-hemorrhagic activity of cinnamic acid analogs against Protobothrops flavoviridis (Habu) venom, it was revealed that the presence of the E-enoic acid moiety (-CH=CH-COOH) was critical. Furthermore, among the compound tested, it was concluded that rosmarinic acid (1) (IC(50) 0.15 μM) was the most potent inhibitor against the venom.  相似文献   
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Previously, we have succeeded in converting induced pluripotent stem cells (iPSCs) into cancer stem cells (CSCs) by treating the iPSCs with conditioned medium of Lewis lung carcinoma (LLC) cells. The converted CSCs, named miPS-LLCcm cells, exhibited the self-renewal, differentiation potential, and potential to form malignant tumors with metastasis. In this study, we further characterized miPS-LLCcm cells both in vivo and in vitro. The tumors formed by subcutaneous injection showed the structures with pathophysiological features consisting of undifferentiated and malignant phenotypes generally found in adenocarcinoma. Metastasis in the lung was also observed as nodule structures. Excising from the tumors, primary cultured cells from the tumor and the nodule showed self-renewal, differentiation potential as well as tumor forming ability, which are the essential characters of CSCs. We then characterized the epigenetic regulation occurring in the CSCs. By comparing the DNA methylation level of CG rich regions, the differentially methylated regions (DMRs) were evaluated in all stages of CSCs when compared with the parental iPSCs. In DMRs, hypomethylation was found superior to hypermethylation in the miPS-LLCcm cells and its derivatives. The hypo- and hypermethylated genes were used to nominate KEGG pathways related with CSC. As a result, several categories were defined in the KEGG pathways from which most related with cancers, significant and high expression of components was PI3K-AKT signaling pathway. Simultaneously, the AKT activation was also confirmed in the CSCs. The PI3K-Akt signaling pathway should be an important pathway for the CSCs established by the treatment with conditioned medium of LLC cells.  相似文献   
107.
Changes in the methylation levels of DNA from white blood cells (WBCs) are putatively associated with an elevated risk for several cancers. The aim of this study was to investigate the association between colorectal cancer (CRC) and the methylation status of three DNA repetitive elements in DNA from peripheral blood. WBC DNA from 539 CRC cases diagnosed before 60 years of age and 242 sex and age frequency-matched healthy controls from the Australasian Colorectal Cancer Family Registry were assessed for methylation across DNA repetitive elements Alu, LINE-1 and Sat2 using MethyLight. The percentage of methylated reference (PMR) of cases and controls was calculated for each marker. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using multivariable logistic regression adjusted for potential confounders. CRC cases demonstrated a significantly higher median PMR for LINE-1 (p < 0.001), Sat2 (p < 0.001) and Alu repeats (p = 0.02) when compared with controls. For each of the DNA repetitive elements, individuals with PMR values in the highest quartile were significantly more likely to have CRC compared with those in the lowest quartile (LINE-1 OR = 2.34, 95%CI = 1.48–3.70; p < 0.001, Alu OR = 1.83, 95%CI = 1.17–2.86; p = 0.01, Sat2 OR = 1.72, 95%CI = 1.10–2.71; p = 0.02). When comparing the OR for the PMR of each marker across subgroups of CRC, only the Alu marker showed a significant difference in the 5-fluoruracil treated and nodal involvement subgroups (both p = 0.002). This association between increasing methylation levels of three DNA repetitive elements in WBC DNA and early-onset CRC is novel and may represent a potential epigenetic biomarker for early CRC detection.  相似文献   
108.
Cripto is a developmental oncoprotein and a member of the epidermal growth factor-Cripto, FRL-1, Cryptic family of extracellular signaling molecules. In addition to having essential functions during embryogenesis, Cripto is highly expressed in tumors and promotes tumorigenesis. During development, Cripto acts as an obligate coreceptor for transforming growth factor beta (TGF-beta) ligands, including nodals, growth and differentiation factor 1 (GDF1), and GDF3. As an oncogene, Cripto is thought to promote tumor growth via mechanisms including activation of mitogenic signaling pathways and antagonism of activin signaling. Here, we provide evidence supporting a novel mechanism in which Cripto inhibits the tumor suppressor function of TGF-beta. Cripto bound TGF-beta and reduced the association of TGF-beta with its type I receptor, TbetaRI. Consistent with its ability to block receptor assembly, Cripto suppressed TGF-beta signaling in multiple cell types and diminished the cytostatic effects of TGF-beta in mammary epithelial cells. Furthermore, targeted disruption of Cripto expression by use of small inhibitory RNA enhanced TGF-beta signaling, indicating that endogenous Cripto plays a role in restraining TGF-beta responses.  相似文献   
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Engulfment in Bacillus subtilis is mediated by two complementary systems, SpoIID, SpoIIM and SpoIIP (DMP), which are essential for engulfment, and the SpoIIQ-SpoIIIAGH (Q-AH) zipper, which provides a secondary engulfment mechanism and recruits other proteins to the septum. We here identify two mechanisms by which DMP localizes to the septum. The first depends on SpoIIB, which is recruited to the septum during division and provides a septal landmark for efficient DMP localization. However, sporangia lacking SpoIIB ultimately localize DMP and complete engulfment, suggesting a second mechanism for DMP localization. This secondary targeting pathway depends on SpoIVFA and SpoIVFB, which are recruited to the septum by the Q-AH zipper. The absence of a detectable localization phenotype in mutants lacking only SpoIVFAB (or Q-AH) suggests that SpoIIB provides the primary DMP localization pathway while SpoIVFAB provides a secondary pathway. In keeping with this hypothesis, the spoIIB spoIVFAB mutant strain has a synergistic engulfment defect at septal thinning (which requires DMP) and is completely defective in DMP localization. Thus, the Q-AH zipper both provides a compensatory mechanism for engulfment when DMP activity is reduced, and indirectly provides a compensatory mechanism for septal localization of DMP when its primary targeting pathway is disrupted.  相似文献   
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