Development of a Recombinant RBD Subunit Vaccine for SARS-CoV-2.

The novel coronavirus pneumonia (COVID-19) pandemic is a great threat to human society and now is still spreading. Although several vaccines have been authorized for emergency use, only one recombinant subunit vaccine has been permitted for widespread use. More subunit vaccines for COVID-19 should be developed in the future.

Global Gene Expression Analysis of the Brainstem in EV71- and CVA16-Infected Gerbils.

Enterovirus 71 (EV71) and coxsackievirus A16 (CVA16) are the two most important pathogens of hand, foot, and mouth disease (HFMD). However, the neuropathogenesis of EV71 and CVA16 has not been elucidated. In our previous study, we established gerbils as a useful model for both EV71 and CVA16 infection.

An adult gerbil model for evaluating potential coxsackievirus A16 vaccine candidates.

A suitable animal model of CVA16 infection is crucial in order to understand its pathogenesis and to help develop antiviral vaccines or screen therapeutic drugs. The neonatal mouse model has a short sensitivity period to CA16 infection, which is a major limitation. In this study, we demonstrate that adult (60-day-old) gerbils are susceptible to CVA16 infection at high doses (10 TCID).

Risk Factors and Preventions of Breast Cancer.

Breast cancer is the second leading cause of cancer deaths among women. The development of breast cancer is a multi-step process involving multiple cell types, and its prevention remains challenging in the world. Early diagnosis of breast cancer is one of the best approaches to prevent this disease.

Capsule switching of Neisseria meningitidis sequence type 7 serogroup A to serogroup X.

Objectives: The bacterial pathogen Neisseria meningitidis is able to escape the currently available capsule-based vaccines by undergoing capsule switching. In this study, we investigated whether capsule switching has occurred in a recently emerged sequence type (ST) 7 serogroup X isolate in China, for which currently no vaccine is available.

Methods: To identify capsule switching breakpoints, the capsule locus and flanking regions of the ST-7 serogroup X isolate and three endemic ST-7 serogroup A isolates were sequenced and compared.

Coxsackievirus A16 induced neurological disorders in young gerbils which could serve as a new animal model for vaccine evaluation.

Coxsackievirus A16 (CA16) is one of the major pathogens associated with human hand, foot, and mouth disease (HFMD) in the Asia-pacific region. Although CA16 infections are generally mild, severe neurological manifestations or even death has been reported. Studies on CA16 pathogenesis and vaccine development are severely hampered because the small animal models that are currently available show major limitations.

[Case-based evaluation of forest ecosystem service function in China.].

The data of valuation of forest ecosystem service function (FESF) in 101 primary case studies of China were collected and obtained based on Specifications for Assessment of Forest Ecosystem Services in China (LY/T 1721-2008). FESF was then analyzed synthetically in terms of value coefficient. The results showed that the average value per unit area (VPUA) of FESF in China was 6.

USPIO assisting degradation of MXC by host/guest-type immobilized laccase in AOT reverse micelle system.

The laccase and ultrasmall superparamagnetic iron oxide nanoparticles (USPIO) have been assembled inside the tubular mesoporous silica via co-adsorption technology to prepare host/guest-type immobilized laccase, which is applied to degrade methoxychlor (MXC) in aqueous and reverse micelle environments. The effects of various parameters on degradation of MXC were studied. Under the optimum conditions, the degradation rate could reach maximum value of 45.

Enterovirus 71 infection causes severe pulmonary lesions in gerbils, meriones unguiculatus, which can be prevented by passive immunization with specific antisera.

Neurogenic pulmonary edema caused by severe brainstem encephalitis is the leading cause of death in young children infected by Enterovirus 71 (EV71). However, no pulmonary lesions have been found in EV71-infected transgenic or non-transgenic mouse models. Development of a suitable animal model is important for studying EV71 pathogenesis and assessing effect of therapeutic approaches.

[Genotype of hantavirus in Zhejiang province].

Objective: To identify the genotype and clades of hantavirus (HV) in Zhejiang province.

Methods: The partial S and M segment of the HV in Zhejiang province were amplified with RT-PCR using genotype-specific primers, and then were sequenced and compared with other known hantaviruses.

Results: The genotype of 11 strains were HTNV and other 7 strains were SEOV by homology and phylogenesis analysis, yet the clade distribution was significantly different among foci of Zhejiang with 5 clades of HTNV and 3 clades of SEOV.

Enterovirus 71-induced neurological disorders in young gerbils, Meriones unguiculatus: development and application of a neurological disease model.

A reliable disease model mimicking Enterovirus 71 (EV71) infection in humans is essential for understanding pathogenesis and for developing a safe and effective vaccine. Commonly used rodent models including mouse or rat models are not suitable for vaccine evaluation because the rodents are resistant to EV71 infection after they reach the age of 6 days. In this study, 21-day-old gerbils inoculated intraperitoneally (IP) with a non mouse-adapted EV71 strain developed neurological lesion-related signs including hind limb paralysis, slowness, ataxia and lethargy similar to those of central nervous system (CNS) infection of EV71 in humans.

[A study of immunoassay by using quantum dots to detect Hantavirus infection].

Objective: To develop a new method to detect anti-Hantavirus IgG antibodies (HV IgG) based on quantum dots (QDs) and indirect immune technique.

Methods: The carbodiimide crosslinking method was used to couple protein G and goat antihuman IgG on the surface of water-solubility QDs. The coverglass covered HV antigen was used as carrier, and QDs-PG-IgG conjugates was used as labeled second antibody to detect the HV-IgG in the serum samples.

[The expression and bioactivity of S gene in Vero-E6 cells using baculovirus vector].

Objective: The S gene of a Hanta Virus (HV) Z10 strain was cloned into a baculovirus shuttle bacmid pDual-CMV contained a CMV promoter to generated a recombinant baculovirus BAC-pDual-CMV-HVS, then the recombinant baculovirus was transfected into Vero-E6 cell. The cells with recombinant baculovirus were applied to the detection of HV antiserum.

Methods: To generate the recombinant baculovirus BAC-pDual-CMV-HVS, the sequence of CMV promoter was obtained from the plasmid pEGFP-N1 by PCR, and subsequently cloned to the baculovirus shuttle bacmid pFastBacDUAL resulting the recombinant plasmid pDual-CMV.

[Molecular evolution analysis of hantaviruses in Zhejiang Province].

In order to analyze the molecular epidemiology of Hantavirus (HV) in Zhejiang Province, the complete M and S genome sequences of 12 HV strains from different hosts and locations in Zhejiang Province of China during the period of 1981-2007 were analyzed on genetic evolution by DNAstar and MEGA 4.0 software in this research. Phylogenetic analyses revealed that HTN and SEO strains were co-circulating in Zhejiang Province, and the difference in sequence similarity and the phylogeny was closely related to the isolated regions, but had no distinct relationship with the isolate year and the host, indicating a relationship between epidemiology of HFRS and the distribution region, especially in HTNV.

[Expression of partial S gene of Hantavirus Z10 in Pichia pastoris].

Objective: The purpose of this study is to express partial S gene of Hantavirus Z10.

Methods: The 300 bp S gene of Z10 strain was synthesized by using a successive PCR method for the optimal expression in Pichia pastoris and subcloned into pMD19-T. The SP300 gene was constructed into pPICZaA and sequenced.

[Study on the transmission of Hantaan virus and Orientia tsutsugamushi by naturally dual infected Leptotrombidium scutellare through stinging].

Objective: To investigate whether Leptotrombidium scutellare could be naturally infected by both Hantaan virus (HV) and Orientia tsutsugamushi (OT) and transmission status by stinging.

Methods: 3459 Leptotrombidium scutellares from mice bodies and 3265 which were free were collected in the epidemic area of hemorrhagic fever with renal syndrome (HFRS) and tsutsugamushi disease.15 days later, the suspensions of lung and spleen of mice with 6 in a group stung by 1, 5 or 10 infected mites were injected intra-cerebrally into other mice for the detection of HV and OT in the next 6 generations of the mice, with immunofluorescent antibody technique (IFAT) and Giemsa staining technique.

[Detection of enterohemorrhagic Escherichia coli O157:H7 by loop-mediated isothermal amplification].

Objective: To develop a loop-mediated isothermal amplification (LAMP) method for rapidly diagnosing of Escherichia coli (EHEC) O157:H7 in pathogen detection department or small-scale laboratories.

Methods: Primers for LAMP test were designed by targeting the antigen coding rfbE of EHEC O157:H7, the Shiga-like toxin stx2 and the fliC encoding gene of H7 flagella antigen, respectively. The reaction condition and reaction system of LAMP were optimized.

[Complete genome sequence analysis of Japanese encephalitis virus newly isolated in China].

Objective: To study the complete genome sequence of Japanese encephalitis virus (JEV) strain XJ69 isolated in ZheJiang province and explore its evolution.

Methods: Overlapping primers were designed according to the full-length genomes from GenBank. RT-PCR was used to amplify the fragments and RT-PCR products were cloned T vector, sequenced and analyzed.

[Development and evaluation of TaqMan-based one-step reverse transcription-polymerase chain reaction assay for the detection of Japanese encephalitis virus].

Objective: To establish a TaqMan based real-time reverse transcription-polymerase chain reaction (RT-PCR) assay for the detection of Japanese encephalitis virus.

Methods: The gene sequences of Japanese encephalitis virus downloaded from the GenBank was aligned, using the biologic software. Specific primers and probes were designed in the conserved region of the C gene for Japanese encephalitis virus.

[Study on the difference of genes and the type identification of hantavirus from Lishui, Zhejiang province].

Objective: To isolate hantavirus from Lishui county--one of the epidemic regions for hemorrhagic fever with renal syndrome (HFRS), in Zhejiang province, and to identify the serotype and molecular/biological characteristics of a new HTN subtype hantavirus (HV) strains, hopefully to provide evidence for HFRS prevention and therapy.

Methods: Data on the host animals was collected from Lishui, Zhejiang province in 2007. Direct immunofluorscece assay was adopted to determine HFRS antigens and the lung tissues from HV infected Vero-E6 cells for HV isolation, then total RNA was extracted from Hantavirus Lishui strains and amplified by RT-PCR M, S segments of strains genome were also cloned and sequenced and compared with those of other strains of HV.

[Molecular characterization and sequence comparison of the M and S segments of Hantavirus ZJ5 strain].

Objective: In order to understand the molecular characters of Hantavirus ZJ5 strain, its complete M and S genome were sequenced and compared with that of other hantavirus strains.

Methods: We prepared the total RNA from ZJ5. Infected cells and the raw or purified RT-PCR product was cloned and sequenced.