35 research outputs found

    The distribution of foreign direct investment in China

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    Foreign direct investment (FDI) has played a major role in China's push toward a market-oriented economy. Recent inflows account for 40 percent of combined flows of FDI to all developing countries, making China the biggest developing country FDI recipient. This record is impressive, but certain problems must be overcome if FDI is to continue to help sustain the country's record growth rate and further its economic development. For one thing, FDI in China is highly concentrated geographically, and its sector distribution is highly uneven. The authors empirically analyze the geographic determinants of FDI in China. They find that FDI's geographical distribution in China is determined mostly by GNP, infrastructure development, level of general education, and coastal location. Althoughthe sectoral distribution of FDI is coming into line with the rest of the world, in the past, FDI has been biased toward speculative types of investment, especially in the real estate sector.International Terrorism&Counterterrorism,Environmental Economics&Policies,Banks&Banking Reform,Foreign Direct Investment,Economic Theory&Research

    Campylobacter jejuni Induces Colitis Through Activation of Mammalian Target of Rapamycin Signaling

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    Campylobacter jejuni is the worldwide leading cause of bacterial-induced enteritis. The molecular and cellular events that lead to campylobacteriosis are poorly understood. We identify mammalian target of rapamycin (mTOR) as a signaling pathway that leads to C jejuni-induced intestinal inflammation

    Inside and Outside Flank Alternate Meshing Silent Chain and Experimental Evaluation of Dynamic Performance

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    Abstract: A new silent chain with inside and outside flank alternating meshing mechanism and sprockets were designed, and the main technical parameters and structure type of the plate and sprocket profile were described. In order to verify the good meshing transmission performance of the new silent chain, we did the performance comparison test for inside and outside flank alternate meshing silent chain and the ANSI standard silent chain with regard to transverse displacement vibration and wear extension. The results show that the new silent chain transmits smoothly, with standard silent chain compared to significantly reduce vibration quantity of transverse displacement, and it has good wear resistance properties, which is much superior to the standard silent chain. The results also verify low impact characteristics of the new silent chain and the rationality of design method. Because of its special meshing mechanism and structure type of alternate load, the new silent chain reduces meshing impact, vibration and polygon effect when chain and sprocket meshes, and fundamentally improves silent chain transmission performance, then extends the life of the chain

    Phosphatidylinositol 3-Kinase-  Signaling Promotes Campylobacter jejuni-Induced Colitis through Neutrophil Recruitment in Mice

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    Crypt abscesses caused by excessive neutrophil accumulation are prominent features of human campylobacteriosis and its associated pathology. The molecular and cellular events responsible for this pathological situation are currently unknown. We investigated the contribution of PI3Kγ signaling in Campylobacter jejuni-induced neutrophil accumulation and intestinal inflammation. Germ-free and specific pathogen free Il10−/−and germ-free Il10−/−; Rag2−/− mice were infected with C. jejuni (109 CFU/mouse). PI3Kγ signaling was manipulated using either the pharmacological PI3Kγ inhibitor AS252424 (i.p. 10 mg/kg daily) or genetically using Pi3γ−/− mice. After up to 14 days, inflammation was assessed histologically and by measuring levels of colonic Il1β, Cxcl2 and Il17a mRNA. Neutrophils were depleted using anti-Gr1 antibody (i.p. 0.5 mg/mouse/every 3 days). Using germ-free Il10−/−; Rag2−/− mice, we observed that innate immune cells are the main cellular compartment responsible for campylobacteriosis. Pharmacological blockade of PI3Kγ signaling diminished C. jejuni-induced intestinal inflammation, neutrophil accumulation and NF-κB activity, which correlated with reduced Il1β (77%), Cxcl2 (73%) and Il17a (72%) mRNA accumulation. Moreover, Pi3kγ−/− mice pretreated with anti-IL-10R were resistant to C. jejuni-induced intestinal inflammation compared to Wt mice. This improvement was accompanied by a reduction of C. jejuni translocation into the colon and extra-intestinal tissues and by attenuation of neutrophil migratory capacity. Furthermore, neutrophil depletion attenuated C. jejuni-induced crypt abscesses and intestinal inflammation. Our findings indicate that C. jejuni-induced PI3Kγ signaling mediates neutrophil recruitment and intestinal inflammation in Il10−/− mice. Selective pharmacological inhibition of PI3Kγ may represent a novel means to alleviate severe cases of campylobacteriosis, especially in antibiotic-resistant strains

    The Role of Immune Response and Microbiota on Campylobacteriosis

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    Million cases of campylobacteriosis and complications of post-Campylobacter jejuni infection occur every year around the world with huge life losses and economic burdens of billions of dollars. Few therapy options, such as antibiotics, are available to relieve severe cases of the enteritis. The slow progression on new intervention discovery and application is partially resulted from limited mechanistic understanding on campylobacteriosis pathogenesis. As a type of intestinal disorders, campylobacteriosis shares many common features with other intestinal diseases such as inflammatory bowel diseases (IBD) and Clostridium difficile infection. In pace with the advancement of the gastroenterology field, a large body of knowledge is accumulating on the factors influencing campylobacteriosis onset, development, and outcomes, including host immune response, intestinal microbiota, and its metabolites. In this chapter, we review the intestinal immune system, intestinal microbiome, and microbiome modulation of inflammation in the development of campylobacteriosis. The interplay between immunity, microbiota, and its metabolites may play essential roles on campylobacteriosis pathogenesis and the finding on the interaction may lead to new prevention and treatment options. The purpose of this chapter is to provide updated knowledge on the role of host–microbe interaction and the therapeutic potential on campylobacteriosis

    Microbial Colonization Induces Dynamic Temporal and Spatial Patterns of NF-κB Activation in the Zebrafish Digestive Tract

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    The nuclear factor κ-light-chain enhancer of activated B cells (NF-κB) transcription factor pathway is activated in response to diverse microbial stimuli to regulate expression of genes involved in immune responses and tissue homeostasis. However, the temporal and spatial activation of NF-κB in response to microbial signals have not been determined in whole living organisms, and the molecular and cellular details of these responses are not well understood. We used in vivo imaging and molecular approaches to analyze NF-κB activation in response to the commensal microbiota in transparent gnotobiotic zebrafish

    Commensal microbiota stimulate systemic neutrophil migration through induction of Serum amyloid A: Microbiota regulate systemic neutrophil function

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    Neutrophils serve critical roles in inflammatory responses to infection and injury, and mechanisms governing their activity represent attractive targets for controlling inflammation. The commensal microbiota is known to regulate the activity of neutrophils and other leucocytes in the intestine, but the systemic impact of the microbiota on neutrophils remains unknown. Here we utilized in vivo imaging in gnotobiotic zebrafish to reveal diverse effects of microbiota colonization on systemic neutrophil development and function. The presence of a microbiota resulted in increased neutrophil number and myeloperoxidase expression, and altered neutrophil localization and migratory behaviours. These effects of the microbiota on neutrophil homeostasis were accompanied by an increased recruitment of neutrophils to injury. Genetic analysis identified the microbiota-induced acute phase protein serum amyloid A (Saa) as a host factor mediating microbial stimulation of tissue-specific neutrophil migratory behaviours. In vitro studies revealed that zebrafish cells respond to Saa exposure by activating NF-κB, and that Saa-dependent neutrophil migration requires NF-κB-dependent gene expression. These results implicate the commensal microbiota as an important environmental factor regulating diverse aspects of systemic neutrophil development and function, and reveal a critical role for a Saa-NF-κB signalling axis in mediating neutrophil migratory responses

    Interferon-alpha responsible EPN3 regulates hepatitis B virus replication

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    Hepatitis B virus (HBV) infection remains a major health problem worldwide, and the current antiviral therapy, including nucleoside analogs, cannot achieve life-long cure, and clarification of antiviral host immunity is necessary for eradication. Here, we found that a clathrin-binding membrane protein epsin3 (EPN3) negatively regulates the expression of HBV RNA. EPN3 expression was induced by transfection of an HBV replicon plasmid, and reduced HBV-RNA level in hepatic cell lines and murine livers hydrodynamically injected with the HBV replicon plasmid. Viral RNA reduction by EPN3 was dependent on transcription, and independent from epsilon structure of viral RNA. Viral RNA reduction by overexpression of p53 or IFN-α treatment, was attenuated by knockdown of EPN3, suggesting its role downstream of IFN-α and p53. Taken together, this study demonstrates the anti-HBV role of EPN3. The mechanism how it decreases HBV transcription is discussed

    Gnotobiotic IL-10−/−; NF-κBEGFP Mice Develop Rapid and Severe Colitis Following Campylobacter jejuni Infection

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    Limited information is available on the molecular mechanisms associated with Campylobacter jejuni (C. jejuni) induced food-borne diarrheal illnesses. In this study, we investigated the function of TLR/NF-κB signaling in C. jejuni induced pathogenesis using gnotobiotic IL-10−/−; NF-κBEGFP mice. In vitro analysis showed that C. jejuni induced IκB phosphorylation, followed by enhanced NF-κB transcriptional activity and increased IL-6, MIP-2α and NOD2 mRNA accumulation in infected-mouse colonic epithelial cells CMT93. Importantly, these events were blocked by molecular delivery of an IκB inhibitor (Ad5IκBAA). NF-κB signalling was also important for C.jejuni-induced cytokine gene expression in bone marrow-derived dendritic cells. Importantly, C. jejuni associated IL-10−/−; NF-κBEGFP mice developed mild (day 5) and severe (day 14) ulcerating colonic inflammation and bloody diarrhea as assessed by colonoscopy and histological analysis. Macroscopic analysis showed elevated EGFP expression indicating NF-κB activation throughout the colon of C. jejuni associated IL-10−/−; NF-κBEGFP mice, while fluorescence microscopy revealed EGFP positive cells to be exclusively located in lamina propria mononuclear cells. Pharmacological NF-κB inhibition using Bay 11-7085 did not ameliorate C. jejuni induced colonic inflammation. Our findings indicate that C. jejuni induces rapid and severe intestinal inflammation in a susceptible host that correlates with enhanced NF-κB activity from lamina propria immune cells
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