8,090 research outputs found
Using Artificial Neural Networks to Produce High-Resolution Soil Property Maps
High-resolution maps of soil property are considered as the most important inputs for decision support and policy-making in agriculture, forestry, flood control, and environmental protection. Commonly, soil properties are mainly obtained from field surveys. Field soil surveys are generally time-consuming and expensive, with a limitation of application throughout a large area. As such, high-resolution soil property maps are only available for small areas, very often, being obtained for research purposes. In the chapter, artificial neural network (ANN) models were introduced to produce high-resolution maps of soil property. It was found that ANNs can be used to predict high-resolution soil texture, soil drainage classes, and soil organic content across landscape with reasonable accuracy and low cost. Expanding applications of the ANNs were also presented
High Diversity of Cytospora Associated With Canker and Dieback of Rosaceae in China, With 10 New Species Described
Cytospora canker is a destructive disease of numerous hosts and causes serious economic losses with a worldwide distribution. Identification of Cytospora species is difficult due to insufficient phylogenetic understanding and overlapped morphological characteristics. In this study, we provide an assessment of 23 Cytospora spp., which covered nine genera of Rosaceae, and focus on 13 species associated with symptomatic branch or twig canker and dieback disease in China. Through morphological observation and multilocus phylogeny of internal transcribed spacer (ITS), large nuclear ribosomal RNA subunit (LSU), actin (act), RNA polymerase II subunit (rpb2), translation elongation factor 1-α (tef1-α), and beta-tubulin (tub2) gene regions, the results indicate 13 distinct lineages with high branch support. These include 10 new Cytospora species, i.e., C. cinnamomea, C. cotoneastricola, C. mali-spectabilis, C. ochracea, C. olivacea, C. pruni-mume, C. rosicola, C. sorbina, C. tibetensis, and C. xinjiangensis and three known taxa including Cytospora erumpens, C. leucostoma, and C. parasitica. This study provides an initial understanding of the taxonomy of Cytospora associated with canker and dieback disease of Rosaceae in China
Modulating effect of adenosine deaminase on function of adenosine A 1 receptors 1
Aim : To study the modulating effect of adenosine deaminase (ADA) on yhe adenosine A 1 receptor (A 1 R) in HEK293 cells stably expressing the human A 1 R. Methods : cDNA was amplified by RT-PCR using total RNA from human embryo brain tissue as the template. The PCR products were subcloned into the plasmid pcDNA3 and cloned into the plasmid pcDNA3.1. The cloned A 1 R cDNA was sequenced and stably expressed in HEK293 cells. The modulating effect of adenosine deaminase on A 1 R was studied by using [ 3 H]DPCPX binding assay and an intracellular calcium assay. Results : HEK293 cells stably expressing human A 1 R were obtained. Saturation studies showed that the K D value and B max value of [ 3 H]DPCPX were 1.6±0.2 nmol/L and 1.819±0.215 nmol/g of protein respectively, in the absence of ecto-ADA respectively, and 1.3±0.2 nmol/L and 1.992±0.130 nmol/g of protein in the presence of ecto-ADA respectively, suggesting that the K D value and B max value of [ 3 H]DPCPX were unaffected by ecto-ADA. In the case of [ 3 H]DPCPX competition curves obtained from intact cells or membranes, A 1 R agonist CCPA/[ 3 H]DPCPX competition curve could be fitted well to a one-site model in the absence of ecto-ADA and a two-site model in the presence of ecto-ADA with a K H value of 0.74 (0.11–4.8) nmol/L (intact cells) or 1.8 (0.25–10) nmol/L (membrane) and a K L value of 0.94 (0.62–1.41) Μmol/L (intact cells) or 0.77 (0.29–0.99) Μmol/L (membrane). The K L value is not significantly different from the EC 50 value of 0.84(0.57–1.23) Μmol/L (intact cells) or 0.84 (0.63–1.12) Μmol/L (membrane) obtained in the absence of ecto-ADA. Similar results were obtained from the CPA/[ 3 H]DPCPX competition curve in the absence or presence of ecto-ADA on intact cells or membranes. Intracellular calcium assay demonstrated that the EC 50 value of CPA were 10 (5–29) nmol/L and 94 (38–229) nmol/L in the presence or absence of ecto-ADA, respectively. Conclusion : A 1 R stably expressed in the HEK293 cells display a low affinity for agonists in the absence of ADA and high and low affinities for agonists in the presence of ADA. The presence of ADA may promote the signaling through the adenosine A 1 receptor in HEK293 cells.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73693/1/j.1745-7254.2005.00524.x.pd
Transcription Factor Phox2 Upregulates Expression of Norepinephrine Transporter and Dopamine β-Hydroxylase in Adult Rat Brains
Degeneration of the noradrenergic locus coeruleus (LC) in aging and neurodegenerative diseases is well documented. Slowing or reversing this effect may have therapeutic implications. Phox2a and Phox2b are homeodomain transcriptional factors that function as determinants of the noradrenergic phenotype during embryogenesis. In the present study, recombinant lentiviral eGFP-Phox2a and -Phox2b (vPhox2a and vPhox2b) were constructed to study the effects of Phox2a/2b over-expression on dopamine β-hydroxylase (DBH) and norepinephrine transporter (NET) levels in central noradrenergic neurons. Microinjection of vPhox2 into the LC of adult rats significantly increased Phox2 mRNA levels in the LC region. Over-expression of either Phox2a or Phox2b in the LC was paralleled by significant increases in mRNA and protein levels of DBH and NET in the LC. Similar increases in DBH and NET protein levels were observed in the hippocampus following vPhox2 microinjection. In the frontal cortex, only NET protein levels were significantly increased by vPhox2 microinjection. Over-expression of Phox2 genes resulted in a significant increase in BrdU-positive cells in the hippocampal dentate gyrus. The present study demonstrates an upregulatory effect of Phox2a and Phox2b on the expression of DBH and NET in noradrenergic neurons of rat brains, an effect not previously shown in adult animals. Phox2 genes may play an important role in maintaining the function of the noradrenergic neurons after birth, and regulation of Phox2 gene expression may have therapeutic utility in aging or disorders involving degeneration of noradrenergic neurons
Integrated gene-based and pathway analyses using UK Biobank data identify novel genes for chronic respiratory diseases
BackgroundChronic respiratory diseases have become a non-negligible cause of death globally. Although smoking and environmental exposures are primary risk factors for chronic respiratory diseases, genetic factors also play an important role in determining individual’s susceptibility to diseases. Here we performed integrated gene-based and pathway analyses to systematically illuminate the heritable characteristics of chronic respiratory diseases.MethodsUK (United Kingdom) Biobank is a very large, population-based prospective study with over 500,000 participants, established to allow detailed investigations of the genetic and nongenetic determinants of the diseases. Utilizing the GWAS-summarized data downloaded from UK Biobank, we conducted gene-based analysis to obtain associations of susceptibility genes with asthma, chronic obstructive pulmonary disease (COPD) and pneumonia using FUSION and MAGMA software. Across the identified susceptibility regions, functional annotation integrating multiple functional data sources was performed to explore potential regulatory mechanisms with INQUISIT algorithm. To further detect the biological process involved in the development of chronic respiratory diseases, we undertook pathway enrichment analysis with the R package (clusterProfiler).ResultsA total of 195 susceptibility genes were identified significantly associated with chronic respiratory diseases (Pbonferroni < 0.05), and 24/195 located out of known susceptibility regions (e.g. WDPCP in 2p15). Within the identified susceptibility regions, functional annotation revealed an aggregation of credible variants in promoter-like and enhancer-like histone modification regions and such regulatory mechanisms were specific to lung tissues. Furthermore, 110 genes with INQUISIT score ≥1 may influence diseases susceptibility through exerting effects on coding sequences, proximal promoter and distal enhancer regulations. Pathway enrichment results showed that these genes were enriched in immune-related processes and nicotinic acetylcholine receptors pathways.ConclusionsThis study implemented an integrated gene-based and pathway strategy to explore the underlying biological mechanisms and our findings may serve as promising targets for future clinical treatments of chronic respiratory diseases
Altered Expression of Phox2 Transcription Factors in the Locus Coeruleus in Major Depressive Disorder Mimicked by Chronic Stress and Corticosterone Treatment in Vivo and in Vitro
Phox2a and Phox2b are two homeodomain transcription factors playing a pivotal role in the development of noradrenergic neurons during the embryonic period. However, their expression and function in adulthood remain to be elucidated. Using human postmortem brain tissues, rat stress models and cultured cells, this study aimed to examine the alteration of Phox2a and Phox2b expression. The results show that Phox2a and Phox2b are normally expressed in the human locus coeruleus (LC) in adulthood. Furthermore, the levels of Phox2a protein and mRNA and protein levels of Phox2b were significantly elevated in the LC of brain donors that suffered from the major depressive disorder, as compared to age-matched and psychiatrically normal control donors. Fischer 344 rats subjected to chronic social defeat showed higher mRNA and protein levels of Phox2a and Phox2b in the LC, as compared to non-stressed control rats. In rats chronically administered oral corticosterone, mRNA and protein levels of Phox2b, but not Phox2a, in the LC were significantly increased. In addition, the corticosterone-induced increase in Phox2b protein was reversed by simultaneous treatment with either mifepristone or spironolactone. Exposing SH-SY5Y cells to corticosterone significantly increased expression of Phox2a and Phox2b, which was blocked by corticosteroid receptor antagonists. Taken together, these experiments reveal that Phox2 genes are expressed throughout the lifetime in the LC of humans and Fischer 344 rats. Alterations in their expression may play a role in major depressive disorder and possibly other stress-related disorders through their modulatory effects on the noradrenergic phenotype
FOXD1 Promotes Cell Growth and Metastasis by Activation of Vimentin in NSCLC
Background/Aims: Forkhead box D1 (FOXD1) has a well-established role in early embryonic development and organogenesis and functions as an oncogene in several cancers. However, the clinical significance and biological roles of FOXD1 in non-small cell lung cancer (NSCLC) remain largely unknown. Methods: A total of 264 primary NSCLC tissue samples were collected. The expression levels of FOXD1 in these samples were examined by immunohistochemical staining. The expression of FOXD1 was knocked down by lentiviral shRNA. The relative expression of FOXD1 was determined by qRT-PCR, Western blotting and immunofluorescence image. The functional roles of FOXD1 in NSCLC were demonstrated cell viability CCK-8 assay, colony formation, cell invasion and migration assays, and cell apoptosis assay in vitro. In vivo mouse xenograft and metastasis models were used to assess tumorigenicity and metastatic ability. The Chi-square test was used to assess the correlation between FOXD1 expression and the clinicopathological characteristics. Survival curves were estimated by Kaplan-Meier method and compared using the log-rank test. The Cox proportional hazards model was used for univariate and multivariate analyses. Results: We determined that higher levels of FOXD1 were present in NSCLC tissues, especially in metastatic NSCLC tissues. FOXD1 was also higher in all NSCLC cells compared with normal human bronchial epithelial cells. A higher expression level of FOXD1 was associated with malignant behavior and poor prognosis in NSCLC patients. Knockdown of FOXD1 significantly inhibited proliferation, migration, and invasion in vitro and tumor growth and metastasis in vivo, and it increased the apoptosis rates of NSCLC cells. Mechanistic analyses revealed that FOXD1 expressed its oncogenic characteristics through activating Vimentin in NSCLC. Multivariate Cox regression analysis indicated that FOXD1 was an independent prognostic factor both for overall survival (OS) and disease-free survival (DFS) in NSCLC patients. Conclusion: Our results indicated that FOXD1 might be involved in the development and progression of NSCLC as an oncogene, and thereby might be a potential therapeutic target for NSCLC patients
Research progress in cardiotoxicity of organophosphate esters
Organophosphate esters (OPEs) have been extensively utilized worldwide as a substitution for brominated flame retardants. With an increased awareness of the need for environmental protection, the potential health risks and ecological hazards of OPEs have attracted widespread attention. As the dynamic organ of the circulatory system, the heart plays a significant role in maintaining normal life activities. Currently, there is a lack of systematic appraisal of the cardiotoxicity of OPEs. This article summarized the effects of OPEs on the morphological structure and physiological functions of the heart. It is found that these chemicals can lead to pericardial edema, abnormal looping, and thinning of atrioventricular walls in the heart, accompanied by alterations in heart rate, with toxic effects varying by the OPE type. These effects are primarily associated with the activation of endoplasmic reticulum stress response, the perturbation of cytoplasmic and intranuclear signal transduction pathways in cardiomyocytes. This paper provides a theoretical basis for further understanding of the toxic effects of OPEs and contributes to environmental protection and OPEs’ ecological risk assessment
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