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In recent years, time series land cover products have been developed rapidly. However, the traditional classification strategy rarely considers time continuity and spatial consistency, which leads to the existence of unreasonable changes among the multi-period products. In order to solve the existing problems, this paper proposes a matrix decomposition model and an optimized hidden Markov model (HMM) to improve the consistency of the time series land cover maps. It also compares the results with the spatio-temporal window filtering model. The spatial weight information is introduced into the singular value decomposition (SVD) model, and the regression model is constructed by combining the eigenvalues and eigenvectors of the image to predict the unreasonable variable pixels and complete the construction of the matrix decomposition model. To solve the two problems of reliance on expert experience and lack of spatial relationships, this paper optimizes the model and proposes the HMM Land Cover Transition (HMM_LCT) model. The overall accuracy of the matrix decomposition model and the HMM_LCT model is 90.74% and 89.87%, respectively. It is found that the matrix decomposition model has a better effect on consistency adjustment than the HMM_LCT model. The matrix decomposition model can also adjust the land cover trajectory to better express the changing trend of surface objects. After consistent adjustment by the matrix decomposition model, the cumulative proportion of the first 15 types of land cover trajectories reached 99.47%, of which 83.01% were stable land classes that had not changed for three years. [ABSTRACT FROM AUTHOR]

Objective: Genome‐wide association studies (GWAS) found NTN1, NOG and the region between CREBBP and ADCY9 were risks to non‐syndromic cleft lip with or without cleft palate (NSCL/P). However, the association of single nucleotide polymorphisms (SNPs) in these genes with NSCL/P in Western China is unknown. Subjects and Methods: We selected seven SNPs in NTN1, NOG and between CREBBP and ADCY9, and then performed transmission disequilibrium test (TDT), parent‐of‐origin effect and sliding window haplotype analysis to test the associations among 302 NSCL/P case–parent trios from Western Han Chinese. Results: We found allele G at rs4791774 in NTN1 was significantly overtransmitted among non‐syndromic cleft lip only (NSCLO) (p = 0.0067, OR = 1.79, 95% CI: 1.17–2.74); rs4791774 and rs9915089 tightly linked with each other among NSCL/P (D′ = 0.87, r2 = 0.67) and haplotypes carrying the risk allele G at rs4791774 were always found to be overtransmitted from parents to cases. Motif analysis indicated that allele G at rs4791774 could greatly alter the affinity of Myc_disc7, so allele G at rs4791774 in NTN1 might modulate C‐MYC transcription to participate in the aetiology of NSCLO. Conclusions: Our study suggested allele G at rs4791774 in NTN1 gene is risk of NSCLO, which could greatly increase the risk to have a baby with cleft. [ABSTRACT FROM AUTHOR]

DNA methylation is an epigenetic event involved in regulation of gene transcription during cell differentiation. DNA methyltransferases (DNMT) play a role in differentiation of neural stem cells into neurons. The aim of this study was to determine whether nerve growth factor (NGF) was involved in differentiation of mouse hippocampal neuronal cell line (HT22) as assessed by IncuCyte. Quantitative PCR and western blot were used to measure gene and protein expression of DNMT as well as the activity of DNMTs. Treatment with NGF was found to upregulate both gene and protein expressions as well as total activity of DNMTs in differentiating HT22 cells. Compared to undifferentiating cells, the percentage of differentiating cells at S phase increased significantly when incubated with NGF. In undifferentiated cells, NGF failed to induce gene and protein expressions and activity of DNMTs. Data demonstrate that differentiation of HT22 cells by exposure to NGF involve the activation of DNMTs pathway. [ABSTRACT FROM AUTHOR]

Epigenetic processes such as DNA methylation are essential for processes of gene expression in normal mammalian development. DNA methyltransferases (DNMT) are responsible for initiating and maintaining DNA methylation. It is known that 5-Aza-CdR, an inhibitor of DNMT induces cytotoxicity by reducing DNMT activity in various tumor cell lines. However, disturbances in neuronal DNA methylation may also play a role in altered brain functions. Thus, it was of interest to determine whether alterations in DNA methylation might be associated with neuronal functions by using 5-Aza-CdR, on mouse hippocampus-derived neuronal HT22 cell line. In particular, the aim of this study was to investigate the effects of 5-Aza-CdR on cell growth inhibition, cell cycle arrest, apoptosis as well as the expression levels of DNMT in HT22 cells. HT22 cells were incubated with 5 or 20 μmol/L 5-Aza-CdR for 24 h. Data showed that 5-Aza-CdR at both concentrations significantly inhibited proliferation of HT22 cells and exacerbated cytoplasmic vacuolization. Flow cytometry analysis demonstrated that 5-Aza-CdR treatment at both concentrations decreased early apoptosis but enhanced late apoptosis. Cell cycle analysis illustrated that 5-Aza-CdR treatment induced S phase arrest. Further, incubation with 5-Aza-CdR produced a down-regulation in expression of mRNA and protein DNMT1 and 3A but no marked changes were noted in DNMT 3B and p21 expression. In addition, DNMT1 activity was significantly decreased at both 5-Aza-CdR concentrations. Evidence indicates that 5-Aza-CdR induced cytotoxicity was associated with altered mRNA and protein expression of DNMT 1 and 3A associated with reduced DNMT1 activity in HT22 cells which might affect brain functions. [ABSTRACT FROM PUBLISHER]

Vanadate is a transition element that present in nature and was shown to be a nonspecific inhibitor of protein tyrosine phosphatases. It was reported that vanadium (Vd) compounds exhibit antitumor actions in several cancer cell lines. This study aimed to examine the antiproliferative and apoptotic actions of different concentrations of sodium vanadate (NaVd) (+5) in esophageal squamous carcinoma cell line EC109 by determining the protein expression levels of cyclin D1 and caspase-3 following incubation for various times from 15 min up to 4 h. In addition, cell proliferation of EC109 treated with different concentrations (NaVd) was also measured using the MTT assay at 4, 12, 24, and 48 h. The cell cycle of EC109 cells exposed to different concentrations of NaVd was detected using flow cytometry determination at 24 h. Data showed that NaVd greater than 100 µMsignificantly increased cyclin D1. In contrast, reduced caspase-3 protein expression levels occurred at 50 µM. Cellular proliferation was significantly decreased at 50uM. The cell cycle was arrested at S phase with 100 µMNaVd. Taken together, data indicate that NaVd produced concentration- and time-dependent antitumor actions in EC109 cell line. [ABSTRACT FROM PUBLISHER]

In order to analyze the effect on the dynamic characteristics of the submunitions when subject to different separation conditions during cluster munitions separation, the separation processes are simulated by combining compressible unsteady Arbitrary Lagrange-Euler equations with a six degree-of-freedom parallel calculation program. The separation dynamic characteristics are calculated for six sets of separation conditions: with initial separation velocities of 8 m/s and 16 m/s, and separation angles of 3°, 5° and 7°. The aerodynamic interaction processes of the shock wave and the nonlinear aerodynamic characteristics are also analyzed. To verify the accuracy of the simulation, supersonic wind tunnel experiments were also carried out, the results of which agreed well with the numerical results. The results reveal that the projectile shock wave acting on the submunition serves to provide the pitching moment for the separation motion and causes a sharp change in the dynamic characteristics. The nonlinear dynamic features are characterized by the shock wave interference process in the different separation options. [ABSTRACT FROM AUTHOR]

Introduction: Rare-earth nanoparticles in the environment and human body pose a potential threat to human health. Although toxic effects of rare-earth nanoparticles have been extensively studied, the effects on the early development are not well understood. In this study, we attempted to explain the toxic effects of neodymium oxide (Nd 2 O 3 ) nanoparticles on early development., Methods: We added the Nd 2 O 3 nanoparticles at different concentrations and recorded the mortality and malformation rate per 24 hrs under a microscope. The live embryos treated with Nd 2 O 3 nanoparticles were imaged as movies and Z step lapses with a confocal microscope, and heart rates were counted for 30 s to measure the cardiac function. The live Tg ( Flk1 :EGFP) transgenic embryos exposed to Nd 2 O 3 nanoparticles were observed under confocal microscope to measure the cerebrovascular development. Subsequently, we extracted the total protein for Western blot at 5 days post-fertilisation (dpf). Embryos were collected to undergo TUNEL staining for apoptosis detection., Results: Nd 2 O 3 nanoparticles disturbed embryo development at high concentrations (>200 μg/mL). The mortality and malformation rate gradually increased in a dose-dependent manner by morphological observation, while the Nd 2 O 3 median lethal concentration (LD50) was 203.4 μg/mL at 120 hrs post-fertilisation (hpf). Furthermore, the Nd 2 O 3 -treated embryos showed severe arrhythmia and reduced heart rate. We also observed the markedly cerebrovascular disappearance at middle concentration (100 and 200 μg/mL). The downregulated autophagy flux in brain blood vessels and increased apoptosis level in neurons might affect vessels sprouting and contribute to the vanished cerebrovascular., Conclusion: The results suggested that the embryos exposed to Nd 2 O 3 activated the apoptosis pathway and induced toxicity and abnormal cardiac/cerebrovascular development., Competing Interests: The authors report no conflicts of interest in this work., (© 2020 Chen et al.)

Background: Non-syndromic cleft lip with or without cleft palate (NSCL/P) are the most common human congenital birth defects with a complex etiology. MAFB has been reported as a candidate gene involved in the pathogenesis of NSCL/P from genome-wide association study (GWAS) findings, and no replication studies have been performed in Western Han Chinese., Objectives: The aim of this study was to investigate the associations of MAFB among NSCL/P trios in Western Han Chinese., Material and Methods: We selected 6 single nucleotide polymorphisms (SNPs) (rs6072081, rs6065259, rs17820943, rs13041247, rs11698025 and rs6102085) near MAFB based on previous GWAS findings and recruited 298 case-parents trios with NSCL/P from Western Han Chinese population, while genotypes were done by SNPscan technology., Results: Strong evidence of an association was found at rs17820943 (p = 0.0023; odds ratio - ORtranmission = 0.7 and 95% confidence interval [CI]: 0.55-0.88) and rs13041247 (p = 0.0023; ORtranmission = 0.7 and 95% CI: 0.55-0.88) among NSCL/P; genotypic transmission-disequilibrium test (TDT) analysis further confirmed this. C/C homozygote at rs17820943 (z = 3.44 and p = 0.00058) and T/T homozygote at rs13041247 (z = 3.14 and p = 0.0017) was over-transmitted among NSCL/P, which indicated they could increase the risk of having an affected baby. Sliding window haplotype analysis showed that haplotypes consisting of C allele at rs17820943 and T allele at rs13041247 were still over-transmitted among NSCL/P (lowest p = 0.0021)., Conclusions: This study further confirmed that the targeted SNPs at MAFB were associated with NSCL/P trios from Western Han Chinese population, which provides more scientific evidence for the future research and genetic counseling.

It is well known that abnormal DNA methylations occur frequently in kidney cancer. However, it remains unclear exactly which types of DNA methyltransferases (DNMT) contribute to the pathologies of kidney cancers. In order to determine the functions of DNA methyltransferase in kidney tumorigenesis on the molecular level, we examined the mRNA expression levels of DNMT1, DNMT3A, DNMT3B, and DNMT3B variants in renal cell carcinoma tissue. Both mRNA and protein levels of DNMT3B4, a splice variant of DNMT3B, were increased in renal cell carcinoma tissue compared with adjacent control tissues. Additionally, Alu elements and long interspersed nuclear elements (LINE-1) were hypomethylated in renal cell carcinoma tissue. Meanwhile, methylation of the promoter for RASSF1A, a tumor suppressor gene, was moderately increased in renal cell carcinoma tissue, while RASSF1A expression was decreased. Thus, our data suggest that the overexpression of DNMT3B4 may play an important role in human kidney tumorigenesis through chromosomal instability and methylation of RASSF1A.