5.An overview of surveillance of avian influenza viruses in wild birds.
Yun ZHU ; Jing-Hong SHI ; Yue-Long SHU
Chinese Journal of Virology 2014;30(3):310-317
Wild birds (mainly Anseriformes and Charadriiformes) are recognized as the natural reservoir of avian influenza viruses (AIVs). The long-term surveillance of AIVs in wild birds has been conducted in North America and Europe since 1970s. More and more surveillance data revealed that all the HA and NA subtypes of AIVs were identified in the wild ducks, shorebirds, and gulls, and the AIVs circulating in wild birds were implicated in the outbreaks of AIVs in poultry and humans. Therefore, the AIVs in wild birds pose huge threat to poultry industry and human health. To gain a better understanding of the ecology and epidemiology of AIVs in wild birds, we summarize the transmission of AIVs between wild birds, poultry, and humans, the main results of surveillance of AIVs in wild birds worldwide and methods for surveillance, and the types of samples and detection methods for AIVs in wild birds, which would be vital for the effective control of avian influenza and response to possible influenza pandemic.
Animals
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Animals, Wild
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virology
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Birds
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virology
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Humans
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Influenza A virus
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genetics
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isolation & purification
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physiology
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Influenza in Birds
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epidemiology
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transmission
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virology
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Influenza, Human
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epidemiology
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transmission
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virology
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Sentinel Surveillance
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veterinary
7.Fabrication of a bionic artificial bone scaffold using a room temperature three dimensional printing technique
Kaifeng LIN ; Shu HE ; Yue SONG ; Zheng WANG ; Long BI ; Guoxian PEI
Chinese Journal of Orthopaedic Trauma 2016;18(5):421-427
Objective To prepare a bionic artificial bone scaffold using a room temperature three dimensional (3D) printing technique and evaluate its biocompatibility and bioactivity in vitro.Methods A room temperature 3D printing technique was applied to fabricate 3D bionic artificial bone scaffolds using collagen/hydroxyapatite.The physico-chemical structure,porosity and mechanical strength of the scaffolds were assessed.The extract liquid of scaffolds was cocultured with bone mesenchymal stem cells (BMSCs) to evaluate the toxicity of scaffolds.There were 3 experimental groups:blank control with no scaffolds,printed scaffolds group and non-printed scaffolds group.The condition of BMSCs on the scaffolds was observed via scanning electron microscopy(SEM) and immunostaining.3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay and SEM were applied to monitor the proliferation of BMSCs on the scaffolds.At last,alkaline phosphatase (ALP) activity and mRNA expression levels of osteogenesis-related genes were detected to assess the osteoinductive property of the scaffolds.Results The 3D printed scaffolds fabricated in the present study were characterized by highly interconnected pores which were controllable and even in size.The cross section of the scaffolds presented an irregular honeycomb-like microstructure.The porosity of printed 3D scaffolds (71.14% ± 2.24%) was significantly higher than that of non-printed scaffolds (59.04% ±2.98%) (P < 0.05).The physico-chemical structures of the materials were preserved after printing without additional cytotoxicity.The MTT results at 7 and 14 days revealed that the printed scaffolds had a significantly more cell numbers than the non-printed scaffolds(P < 0.05).SEM showed that the BMSCs adhered well onto the printed scaffolds and proliferated and migrated through the pores.Compared with the blank control,the printed scaffolds showed obviously better osteogenic outcomes.Conclusion The 3D bionic artificial bone scaffolds of collagen/hydroxyapatite manufactured by a room temperature 3D printing technique can provide a good extracellular matrix for BMSCs to proliferate and differentiate.
8.Expression of a Novo Human Osteoprotegerin-Mycobacterial Heat Shock 70 Fusion Protein with Baculovirus-Insect Expression System
Shu LIU ; Quan-Geng ZHANG ; Yue ZHANG ; Jing MA ; Zhen-Long LIU ; Wen-Ming ZHAO ;
China Biotechnology 2006;0(05):-
Objective:Osteoprotegerin (OPG) is a key molecule negatively regulating osteoclast differentiation and activation; and the conserved mycobacterial heat shock 70 (HSP70) peptide p111-125 has also been found to inhibit inflammation reactions in chronic arthritis. BaculoDirectTM baculovirus expression system was selected to express recombinant OPG-HSP70 in insect cells.Methods:The human functional fragment (p22-194) of OPG and functional fragment (p111-125) of mycobacterial HSP70 gene were cloned into the transfer vector pENTRTM/SD/D-TOPO. The recombinant plasmid was performed an LR reaction with the BaculoDirectTM Linear DNA to generate recombinant baculovirus DNA. The cultured Sf9 insect cells were directly transferred with the recombinant baculovirus DNA,and the pure recombinant baculovirus was obtained. Then recombinant baculovirus was infected Sf9 insect cells again to express the OPG-HSP70 gene.Results:The target protein was detected at the time of 48h post infection,reached at highest yield at the time of 72h post-infection. A 28kDa protein immunostaining band was detected by Western blotting from lysate of those cells.And the purified protein was obtained by using Ni-NTA system. Functional stuies on the fusion protein showed it significantly reduce osteoclast cell number[(3.10?0.640) cells under each microscope field in treatment group by comparing to (10.70?0.817)cells in the control group] in the osteoclast inhibition test,and reduce the inflammation reaction in a delayed type hypersensitivity (DTH) mice model (P
9.Biphasic calcium phosphate/polyvinyl alcohol scaffolds prepared by 3D-printing at room temperature and their impact on in vitro osteogenic differentiation
Yue SONG ; Kaifeng LIN ; Shu HE ; Shuaishuai ZHANG ; Bin LIU ; Long BI ; Guoxian PEI
Chinese Journal of Orthopaedic Trauma 2017;19(5):409-416
Objective To prepare biphasic calcium phosphate/polyvinyl alcohol scaffolds by 3D printing at room temperature and explore the effect of 3D scaffolds on in vitro osteogenic differentiation of the bone marrow mesenchymal stem cells (BMSCs).Methods After biphasic calcium phosphate and polyvinyl alcohol solutions were mixed,the biphasic calcium phosphate/polyvinyl alcohol composite scaffolds were prepared by room temperature 3D printing combined with freeze drying technique.Non-printing scaffolds were prepared by injection molding.The surface microstructure,porosity,elastic modulus and hydrophilicity of the 2 sorts of scaffolds were measured.The cytological experiments were carried out in 3 groups (n =3):printed scaffold group,non-printed scaffold group and blank control group (no scaffold).After the BMSCs were seeded onto the scaffolds for 7 and 14 days,the 3 groups were compared in terms of cellular proliferation,alkaline phosphatase activity and expression levels of osteogenesis-related genes.Results 3D composite scaffolds with controllable pore size and porosity were prepared successfully,with an average porosity of 59.6% ± 3.6% and an average elastic modulus of 429.3 ± 54.3 kPa.After culture for 7 and 14 days,the cellular absorbance values in the printed scaffold group (0.987 ± 0.047 and 1.497 ± 0.076) were significantly higher than those in the non-printed scaffold group (0.767 ±0.063 and 1.181 ±0.098) (P < 0.05) which were in turn significantly higher than those in the blank control group (0.532 ±0.046 and 0.895 ± 0.062) (P < 0.05).After culture for 7 and 14 days,the ALP activity and expression levels of osteogenesis-related genes in the printed and non-printed scaffold groups showed no significant between-group differences (P > 0.05),but were significantly higher than those in the blank control group (P < 0.05).Conclusions Tissue-engineered composite biphasic calcium phosphate/polyvinyl alcohol scaffolds with controllable pore size and good connectivity can be prepared by freeze-drying and room temperature 3D printing techniques.Co-culture of the scaffolds and BMSCs in vitro promotes adhesion,proliferation and osteogenic differentiation of the cells.
10.Advances in research and development of universal influenza vaccines.
Li-Xia ZHANG ; Jian-Fang ZHOU ; Yue-Long SHU ; Bao-Shou YANG ; Zhao-Qing HE
Chinese Journal of Virology 2014;30(1):73-78
Vaccination is the primary strategy for the prevention and control of pandemic influenza. Because influenza virus is highly variable across strains, universal influenza vaccines need to be developed to address this problem. This review describes the research progress in conserved epitopes of influenza virus, the advances in the research and development of universal influenza vaccines based on the relatively conserved sequences of NP, M2e, HA2, and headless HA, the mechanisms of cross-protection, and the methods to improve cross-protection.
Animals
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Cross Reactions
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Humans
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Orthomyxoviridae
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immunology
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Species Specificity
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Viral Proteins
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immunology
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Viral Vaccines
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genetics
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immunology