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Preeclampsia is a common pregnancy-specific disorder characterized by elevated blood pressure and proteinuria. Activation of the maternal immune system and impaired placental angiogenesis are thought to contribute to the pathogenesis of preeclampsia. TLR9 (Toll-like receptor 9) plays a role in innate immunity, defending the organism against infection. The purpose of this study was to determine whether TLR9 inhibits angiogenesis at the fetomaternal interface under conditions of preeclampsia. We confirmed the downregulation of VEGFA (vascular endothelial growth factor A) and upregulation of TLR9 and sFLT1 (soluble vascular endothelial growth factor receptor 1) in placentas from preeclamptic women. Then, we established a mouse model with preeclampsia-like symptoms using the synthetic TLR9 agonist CpG (cytidine-phosphate-guanosine)-ODN (oligodeoxynucleotide; ODN1826). We observed the downregulation of VEGFA and the upregulation of sFLT1 in placentas from the preeclampsia-like animal model and in trophoblasts treated with CpG-ODN (ODN2006). In addition, silencing TLR9 promoted the migration and invasion of HTR8/SVneo cells. In conclusion, TLR9 is capable of robustly suppressing angiogenesis by differentially regulating the expression of VEGFA and sFLT1 at the fetomaternal interface, potentially contributing to the development of preeclampsia.

DNA methyltransferases (DNMTs) 1, 3a, and 3b affect DNA promoter methylation; studies have suggested that they have important roles in the development of cancers. In this study, we analyzed the expression of DNMTs 1, 3a, and 3b; the MIB-1 labeling index; and their clinical significance in 6 normal retinas and 62 retinoblastomas using immunohistochemical analysis. We found that DNMT proteins were not expressed in normal retinas, whereas they were frequently expressed in retinoblastomas (DNMT1, 100%; DNMT3a, 98%; and DNMT3b, 92%). Compared with well-differentiated retinoblastomas, the expression of DNMTs 1 and 3a significantly increased in poorly differentiated retinoblastomas (P = .002 and P = .003, respectively); in addition, the frequency of their increased expression was high. DNMT1 expression was significantly higher in invasive retinoblastoma. Furthermore, the expression of DNMTs was positively correlated with the MIB-1 labeling index in retinoblastoma. Our findings suggest that the overexpression of DNMTs 1, 3a, and 3b may be related to retinoblastoma tumorigenesis and progression and may represent a novel approach for retinoblastoma therapy.

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Vegetation restoration potential mapping (VRPM) is of great importance for regional ecosystem restoration planning after long‐term land degradation or short‐term disasters. However, there are some problems to be solved in the current models for evaluating the potential of vegetation restoration. First, the models for VRPM are mostly established based on a knowledge‐driven index system. Although this kind of model is logically rigorous, it relies too much on expert knowledge and is relatively inefficient, especially for large‐area vegetation restoration assessments. Second, because of the spatial heterogeneity, as well as the absence of important indicators, the traditional global‐based evaluation models are difficult to adapt to the entire study area. In this study, an improved data‐driven approach, that is, a sliding‐window based similar habitat potential model, is developed for VRPM. The advantages of the new model include: (a) it is more efficient in determining the importance of each influencing factor without resorting to expert knowledge; (b) it is more locally adaptive than the global model because it performs sample training, rule building, and vegetation restoration potential calculation in each current local window. We provide a case‐study to show the modeling process and result interpretation of the new model.

Aims: To evaluate the association between vascular endothelial growth factor (VEGF) gene polymorphism and the risk of neovascular age-related macular degeneration (AMD) in a case-control study in a Chinese cohort. Methods: We genotyped 4 common single-nucleotide polymorphisms (SNPs), namely –460T/C (rs833061), +405C/G (rs2010963), +674C/T (rs1413711) and +936C/T (rs3025039), simultaneously detected 7 tag SNPs (tSNPs) in the VEGF gene, in 159 neovascular AMD patients and 140 age- and sex-matched control subjects. Genetic analyses for an additive, dominant and recessive model were performed on all available genotype data. All the possible haplotypes of these 11 SNPs were detected. Results: No evident association was found in the allele frequencies of any individual SNP between patients and controls; the combined p values in each genotype group were greater than 0.05. Haplotype analyses of these SNPs did not provide any evidence for an association with the risk of neovascular AMD in this Chinese cohort (p > 0.05). Conclusions: Detection of 4 common SNPs and 7 tSNPs in the VEGF gene did not find any statistically significant association with neovascular AMD in the Chinese cohort. Further studies of comprehensive VEGF gene variations are required to characterize the susceptibility of the VEGF gene in the pathogenesis of AMD.

Landscape fragmentation and habitat loss are one of the important factors resulting in biodiversity decrease and species extinction. A large amount of Eucalyptus have been introduced into Yunnan Province in China since 2003, replaced the native forest, farmland, wasteland and other ecosystems, leading to natural habitat loss and landscape fragmentation. In order to protect habitat and the biodiversity, the secondary ever green broad leaved forest were selected as "protection source", land cover types, altitude, slope and soil tex ture were selected as resistance factors, to construct a medium security and high security level landscape eco security patterns for Eucalyptus introduction regions by using the minimum cumulative resistance model and GIS technology. The patterns were composed of the eco security pattern compositions and ecological function zones. The eco security pattern compositions were composed of corridor, radiating routes and stra tegic point etc. The ecological function zones were composed of key eco protection zone, eco buffer zone, eco transition zone, Eucalyptus planting zone, Eucalyptus banned zones, farming zone, living zone etc.