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It is of great significance to reveal the changes of grain production pattern and natural resource utilization efficiency for rational utilization of natural resources, security of national food security, and sustainable development. Base on the data of county-scale grain production and 683 meteorological stations from 1985 to 2015 in China, ArcGIS spatial analysis method was adopted to analyze the grain production pattern changes and heat resource utilization characteristics considered temperature zone division. Studies had shown that about 90% of Chinese total grain output was produced in mid temperate, warm temperate, northern subtropical, and mid subtropical zones from 1985 to 2015, accounting for 18.6%, 25.6%, 21.6%, and 25.9%, respectively. In the past 30 years, the proportion of grain production in the single cropping region had increased by 13.8%, while it had decreased by 2.7% and 11.2% in the double and triple cropping region, respectively. The proportion of grain production had increased by 13.9% in the mid temperate zone of the single cropping region which was drove by the advance of planted acreage and yield, while the proportion decreased by 13.9% in the subtropical zones of the triple-cropping system. Over the past 30 years, the annual accumulated temperature above 10 °C had continued to increase in different temperature zones, and that was more evident in southern region than northern region. However, the increased magnitude of heat utilization efficiency for grain production in southern temperature zones was lower than northern region. There was a "dislocation phenomenon" between the changes of Chinese grain production pattern and the distributions of heat resources. Therefore, it was necessary to consider the coordination of grain production and natural resources matching as well as the characteristics of resource utilization for improving resource utilization efficiency when optimizing the layout of regional grain production and formulating strategies in China. [ABSTRACT FROM AUTHOR]

Summary: News series of substituted quinazoline derivatives has been synthesized from 3,4-dihydro-7-methoxy-4-oxoquinazoline-6-yl acetate(1) by five-step procedures including chlorination, amination, hydrolysis and etherification. The structures of target compounds were confirmed by IR,1H-NMR, element analysis and single-crystal X-ray diffraction. The results showed that the compound 8c exhibited remarkable inhibitory activity against MCF-7 cell lines with inhibition rate value of 38.45%, which was comparable to that of the positive control Gefitinib(inhibition rate = 13.25% for MCF-7). The initial relationship between structure and activity was worth further exploration. [ABSTRACT FROM AUTHOR]

The continual emergence of tick-borne rickettsioses has garnered widespread global attention. Candidatus Rickettsia barbariae ( Candidatus R. barbariae), which emerged in Italy in 2008, has been detected in humans from northwestern China. However, the lack of Candidatus R. barbariae genome and isolated strains limits the understanding of its biological characteristics and genomic features. Here, we isolated the Rickettsia for the first time from eggs of Rhipicephalus turanicus in northwestern China, and assembled its whole genome after next-generation sequencing, so we modified the proposed name to Rickettsia barbariae ( R. barbariae ) to conform to the International Code of Nomenclature of Prokaryotes. Phylogenetic analysis based on the whole genome revealed that it was most closely related to the pathogenic Rickettsia parkeri and Rickettsia africae . All virulence factors, present in the pathogenic spotted fever group rickettsiae, were identified in the R. barbariae isolate. These findings highlight the pathogenic potential of R. barbariae and the necessity for enhanced surveillance of the emerging Rickettsia in the human population.

Background: This study was designed to obtain a recombinant retroviral vector containing the human hepatocellular carcinoma-related gene ANGPTL4 (angiopoietin-like 4) cDNA and to evaluate the anti-tumor effect of recombinant retroviral vector-mediated human ANGPTL4 gene transfection., Methods: ANGPTL4 cDNA was cloned in vitro from normal human liver cells HL-7702 by using RT-PCR, and then subcloned into the plasmid vector pMSCV and sequenced. The retroviral plasmid vectors pMSCV-ANGPTL4, pVSV, and pGAG-POL were co-transfected into the packaging cell line 293 EBNA under mediation of lipofectamine. A high-titer retrovirus was obtained as a result, and HepG2 cells were infected with this retrovirus in vitro. Flow cytometry and fluorescence microscopy were used to detect expression of green fluorescence protein (GFP). The expression of ANGPTL4 mRNA in HepG2-ANGPTL4 cells was investigated using RT-PCR. The formation of tumors in nude mice and MTT assays were used to detect the growth of HepG2-ANGPTL4 cells in vivo and in vitro, respectively., Results: The cDNA sequence of the cloned ANGPTL4 gene was consistent with the recently reported sequence. Thus, the recombinant retroviral vector pMSCV-ANGPTL4 was constructed successfully. The titer of the packaged recombinant retrovirus was 1.4 x 10(6) infective viral grains/ml, and the rate of HepG2-ANGPTL4 cells expressing GFP was 68.45%, with an average intensity of fluorescence 31.67 times greater in HepG2-ANGPTL4 cells than in HepG2 cells. The expression of ANGPTL4 mRNA in HepG2-ANGPTL4 cells was higher than in HepG2-pMSCV cells (154% higher) or HepG2 cells (161% higher). The proliferation rate of HepG2-ANGPTL4 cells in vitro was obviously lower than those of HepG2-pMSCV cells and HepG2 cells (P <0.01). The mean volume and weight of tumors seeded from HepG2-ANGPTL4 cells were obviously lower than the mean volume or weight of tumors seeded from HepG2 cells and HepG2-pMSCV cells (P <0.01)., Conclusion: A stable ANGPTL4-transfected human liver cancer cell line HepG2-ANGPTL4 has been created. The transfer of the human ANGPTL4 gene mediated by a retroviral vector is a possibly effective approach for liver cancer therapy.