1,919 research outputs found

    6-Chloro-9-(2-nitro­phenyl­sulfon­yl)-9H-purine

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    The title compound, C11H6ClN5O4S, crystallized with two independent mol­ecules in the asymmetric unit. The benzene ring makes dihedral angles of 66.46 (8) and 85.77 (9)° with the mean plane of the purine ring in the two mol­ecules. In the crystal, inter­molecular π–π stacking inter­actions [centroid–centroid distance = 3.8968 (12) Å], C—Cl⋯π inter­actions [Cl⋯centroid = 3.2505 (10) Å, C—Cl⋯centroid = 161.56 (18)°] and non-classical C—H⋯O and C—H⋯N hydrogen bonds link the molecules

    Tiling microarray analysis of rice chromosome 10 to identify the transcriptome and relate its expression to chromosomal architecture

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    BACKGROUND: Sequencing and annotation of the genome of rice (Oryza sativa) have generated gene models in numbers that top all other fully sequenced species, with many lacking recognizable sequence homology to known genes. Experimental evaluation of these gene models and identification of new models will facilitate rice genome annotation and the application of this knowledge to other more complex cereal genomes. RESULTS: We report here an analysis of the chromosome 10 transcriptome of the two major rice subspecies, japonica and indica, using oligonucleotide tiling microarrays. This analysis detected expression of approximately three-quarters of the gene models without previous experimental evidence in both subspecies. Cloning and sequence analysis of the previously unsupported models suggests that the predicted gene structure of nearly half of those models needs improvement. Coupled with comparative gene model mapping, the tiling microarray analysis identified 549 new models for the japonica chromosome, representing an 18% increase in the annotated protein-coding capacity. Furthermore, an asymmetric distribution of genome elements along the chromosome was found that coincides with the cytological definition of the heterochromatin and euchromatin domains. The heterochromatin domain appears to associate with distinct chromosome level transcriptional activities under normal and stress conditions. CONCLUSION: These results demonstrated the utility of genome tiling microarray in evaluating annotated rice gene models and in identifying novel transcriptional units. The tiling microarray sanalysis further revealed a chromosome-wide transcription pattern that suggests a role for transposable element-enriched heterochromatin in shaping global transcription in response to environmental changes in rice

    Factors affecting perceived health benefits and use behaviors in urban green spaces during the COVID-19 pandemic in southern China megacities

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    Background: The COVID-19 pandemic has alienated people from urban green spaces (UGSs) that have various health outcomes for humans. However, little is known about the influential factors of perceived health benefits and use behaviors in UGSs during the COVID-19 pandemic. This study aims to explore the key factors that influence perceived health benefits and use behaviors in UGSs and to assess the mediating role of place attachment in relationships during the COVID-19 pandemic in Chinese megacities. Methods: We conducted an online questionnaire survey from December 2020 to March 2021 in Guangzhou and Shenzhen, China. Six multiple regression models were constructed to investigate the main factors by which UGSs influence citizens' perceived health benefits and use behaviors. Four mediation models were established using the structural equation modeling (SEM) method to explore the mediating effect of place attachment. Results: A total of 628 questionnaires were included in the analysis. The results revealed that some UGS components (green space access, maintenance, and soundscape) significantly affected perceived health benefits for citizens (physical, mental, and social health) during the COVID-19 pandemic. Conversely, use behaviors (frequency of visits, duration of visits, and activity intensity) were mainly affected by the sociodemographic context but less affected by UGS components. In addition, UGS components were found to significantly predict place attachment, which in turn influenced the perceived health benefits, frequency, and duration of visits. Conclusions: This study distinguished the key factors that affect perceived health benefits and use behaviors during the COVID-19 pandemic: green space access, maintenance, soundscape, and sociodemographic characteristics. Place attachment still needs to be considered when discussing how to encourage citizens to visit UGSs during the pandemic. These findings provide implications for policymakers and landscape planners regarding design and management measures for UGSs that are conducive to coping with pandemics

    Exosomal miR-27a Derived from Gastric Cancer Cells Regulates the Transformation of Fibroblasts into Cancer-Associated Fibroblasts

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    Background/Aims: The malignant biological behavior of gastric cancer(GC) is not only determined by cancer cells alone, but also closely regulated by the microenvironment. Fibroblasts represent a large proportion of the components in the tumor microenvironment, and they promote the development of disease. Currently, accumulating evidence suggests that exosomes can function as intercellular transport systems to relay their contents, especially microRNAs(miRNAs). Methods: First, we detected the highly-expressed level of miR-27a in exosomes isolated from gastric cancer cells by qRT-PCR. MiR-27a –over-expressed models in vitro and in vivo were established to investigate the transformation of cancer-associated fibroblasts observed by Western blotting, and the malignant behavior of gastric cancer cells using the methods CCK8 and Transwell. Moreover, the downregulation of CSRP2 in fibroblasts was used to evaluate the promotion of malignancy of gastric cancer using the methods CCK8 and Transwell. Results: In this study, we found a marked high level of miR-27a in exosomes derived from GC cells. miR-27a was found to function an oncogene that not only induced the reprogramming of fibroblasts into cancer-associated fibroblasts(CAFs), but also promoted the proliferation, motility and metastasis of cancer cells in vitro and in vivo. Conversely, CAFs with over-expression of miR-27a could pleiotropically increase the malignant behavior of the GC cells. For the first time, we revealed that CSRP2 is a downstream target of miR-27a. CSRP2 downregulation could increase the proliferation and motility of GC cells. Conclusion: Thus, this report indicates that miR-27a in exosomes derived from GC cells has a crucial impact on the microenvironment and may be used as a potential therapeutic target in the treatment of G

    China–Africa cooperation initiatives in malaria control and elimination

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    Malaria has affected human health globally with a significant burden of disease, and also has impeded social and economic development in the areas where it is present. In Africa, many countries have faced serious challenges in controlling malaria, in part due to major limitations in public health systems and primary health care infrastructure. Although China is a developing country, a set of control strategies and measures in different local settings have been implemented successfully by the National Malaria Control Programme over the last 60 years, with a low cost of investment. It is expected that Chinese experience may benefit malaria control in Africa. This review will address the importance and possibility of China–Africa collaboration in control of malaria in targeted African countries, as well as how to proceed toward the goal of elimination where this is technically feasible.China UK Global Health Support Programme (grant no.GHSP-CS-OP1, OP2, OP3).http://www.elsevier.com/books/book-series/advances-in-parasitologyhb201

    A new measurement of antineutrino oscillation with the full detector configuration at Daya Bay

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    We report a new measurement of electron antineutrino disappearance using the fully-constructed Daya Bay Reactor Neutrino Experiment. The final two of eight antineutrino detectors were installed in the summer of 2012. Including the 404 days of data collected from October 2012 to November 2013 resulted in a total exposure of 6.9×\times105^5 GWth_{\rm th}-ton-days, a 3.6 times increase over our previous results. Improvements in energy calibration limited variations between detectors to 0.2%. Removal of six 241^{241}Am-13^{13}C radioactive calibration sources reduced the background by a factor of two for the detectors in the experimental hall furthest from the reactors. Direct prediction of the antineutrino signal in the far detectors based on the measurements in the near detectors explicitly minimized the dependence of the measurement on models of reactor antineutrino emission. The uncertainties in our estimates of sin22θ13\sin^{2}2\theta_{13} and Δmee2|\Delta m^2_{ee}| were halved as a result of these improvements. Analysis of the relative antineutrino rates and energy spectra between detectors gave sin22θ13=0.084±0.005\sin^{2}2\theta_{13} = 0.084\pm0.005 and Δmee2=(2.42±0.11)×103|\Delta m^{2}_{ee}|= (2.42\pm0.11) \times 10^{-3} eV2^2 in the three-neutrino framework.Comment: Updated to match final published versio
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