Objective To evaluate the radiation protection of occupational hazards in a hospital Clinac 23EX medical electronic accelerator construction project so as to ensure the health and safety of the relevant people involved.Methods According to the relevant laws,regulations and standards of China,combined with the relevant materials provided by the construction unit,the radiation protection tests and comprehensive assessment of this project were carried out.Results The performance test results of the medical electron accelerator met the requinements of GB/T 19046-2013 The ambient dose equivalent rate in the workplace was between the background dose rate (0.10 μ,Sv/h) and 11.5 μSv/h,which suggested the computer room shielding met the requirements of radiation protection.The total body effective dose,the for 7 radiation workers were 0.85,1.19,1.64 mSv,respectively,which were lower than the dose management control values of the construction unit and the national standards.Radiation protection supplies and the management system of the construction unit met the national requirements.Conclusions The construction project can effectively control the radioactive occupational hazard factors in normal operation,and the radiation protection facilities have reached the completion requirements.

OBJECTIVETo evaluate the seasonal influenza spilt vaccine's immunogenicity and the 50% effective dose (ED50a) of hemagglutin (HA) that can make 50% of the mice hemagglutination inhibition antibody (HI) titers to 40.

METHODSThe 2008-2009 seasonal influenza spilt vaccine's two components, with HA from H1N1 and H3N2 influenza virus respectively, were used as a model. Mice were immunized once or twice with different doses, and the HI antibody titers were tested to determine the immunization procedure and to evaluate the immugenicity of seasonal influenza spilt vaccine in mice; Consequently, HI antibody response kinetics of the two components were observed to determine the time point when the HI antibody titer reached the peak point; Finally, mice were immunized with different doses of HA to evaluate the ED50a that can make 50% of mice HI titers reach 40.

RESULTSImmunization procedures study showed that one-dose of seasonal influenza vaccine induced the HI antibody titers ranged from 10 to 120, while two-dose of influenza vaccine improved the HI antibody titer 10-100 times as compared with one dose; antibody kinetics study suggested that the time point of HI antibody produced to peak is 28-35 days post one dose immunization; and the ED50a detection results indicated that one dose of 1.5 microg HA could make 50% of the mice HI antibody titer reach 40.

CONCLUSIONSeasonal influenza spilt vaccine is very immunogenic in mouse; the time point of HI antibody produced to peak is 28-35 days post one dose immunization; and the ED50a of HA is 1.5 microg, which can make 50% of the mice HI titer reach 40. The experimental results provided foundation for the establishment of influenza vaccine evaluation system based on seasonal influenza vaccine.

Animals ; Disease Models, Animal ; Dose-Response Relationship, Drug ; Female ; Hemagglutination Inhibition Tests ; Hemagglutinins, Viral ; administration & dosage ; immunology ; Humans ; Influenza A Virus, H1N1 Subtype ; immunology ; Influenza A Virus, H3N2 Subtype ; immunology ; Influenza Vaccines ; administration & dosage ; immunology ; Influenza, Human ; immunology ; prevention & control ; virology ; Male ; Mice ; Mice, Inbred BALB C ; Seasons

OBJECTIVETo know the etiology, prevalence, clinical symptoms associated with the infection of the HCoV-229E in the respiratory specimens sampled from adult patients in Beijing.

METHODS158 nasopharyngeal swab specimens were collected from adult patients with fever in Beijing between October and December, 2007. We performed the screening of HCoV-229E by real-time RT-PCR and sequencing of HCoV-229E gene fragments derived from conventional PCR. At meantime, we also screened the HCoV-229E positive samples for the co-infection with HCoV-NL63, HCoV-HKU1 and HMPV by real-time RT-PCR. Finally, demographic and clinical data associated with HCoV-229E infection were examined retrospectively.

RESULTSWe detected 103 (62.5%) of 158 specimens were positive for HCoV-229E by real-time RT-PCR. When tested for other respiratory viruses, 26 HCoV-229E positive patients were found to be co-infected with other viruses. Of which HCoV-NL63 was observed in 3 specimens (11.5%), HCoV-HKU1 in 3 (11.5%) and HMPV in 20 (76.9%). The main clinical manifestations were noted as: headache (in 70.9%), sore throat (69%), chills (68%), cough (33%), sputum (21.3%), rhinorrhea (21.4%), nasal obstruction (16.5%), and a few of patients were visible as vomiting (6.8%), dyspnea (3.9%), diarrhea (in 1.9%). The rate of HCoV-229E infection in adult patients was found no relative with age and gender.

CONCLUSIONOur data showed that HCoV-229E is a common and important pathogen in adult patients with acute respiratory symptoms but usually resulted in milder influenza-like illnesses. There might have a local outbreak of HCoV-229E infection in Beijing, Oct-Dec, 2007.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; China ; epidemiology ; Coronavirus 229E, Human ; classification ; genetics ; isolation & purification ; Coronavirus Infections ; diagnosis ; epidemiology ; virology ; Female ; Humans ; Male ; Middle Aged ; Molecular Sequence Data ; Phylogeny ; Respiratory Tract Infections ; diagnosis ; epidemiology ; virology ; Retrospective Studies ; Young Adult

We designed specific primers and fluorescence-labeled probes to develop real-time and conventional RT-PCR assays for detection of human coronavirus NL63 or HKU1. Subsequently, experiments were undertaken to assess diagnostic criteria such as specificity, sensitivity and reproducibility. The detection limit of the real-time RT-PCR assays was 10 RNA copies per reaction mixture. No cross-reactivity was observed between RNA samples derived from designed HCoV and other HCoV or human metapneumovirus. A total of 158 nasopharyngeal swab specimens collected from adult patients with acute respiratory tract infection in Beijing were screened for the presence of human coronavirus NL63 and HKU1 by using real-time RT-PCR and conventional RT-PCR method. The fluorescence quantitative RT-PCR method detected six specimens positive for human coronavirus NL63, five specimens positive for human coronavirus HKU1; and conventional RT-PCR method detected three HCoV-NL63 positive and three HCoV-HKU1 positive, respectively. The convention RT-PCR products of positive samples were obtained and sequence analysis confirmed the reliability of the above methods. In summary, the real-time RT-PCR assay for HCoV- NL63 or HKU1 was more sensitive than conventional RT-PCR and with less time (less than 4 hours) for completion. It may be suitable for molecular epidemiological surveillance and clinical diagnosis for human coronavirus NL63 and HKU1.
Coronavirus ; classification ; genetics ; isolation & purification ; Humans ; Nasopharynx ; virology ; Phylogeny ; Reverse Transcriptase Polymerase Chain Reaction ; methods ; Sensitivity and Specificity

OBJECTIVETo rational design HBV therapeutic vaccine candidate and evaluate their specific immunity to HBV in mice.

METHODSBased on our previous data of HBV protein vaccine consisting of S-PreS1 fusion particle. We first construct a novel DNA vaccine candidate, pVRC-HBSS1, which consisting of S (aa: 1-223) and PreS1 (aa: 21-47) fuse gene,then confirm the expression of the DNA vaccine by Western blotting, and followed by vaccination using prime boost strategy, ie, Intradermal injection of DNA vaccine with gene electroporation (EP) in BALB/c mice after twice injection of different HBSS1 protein vaccines (combination with different adjuvants). The immune response was measured by ELISA and IFN-gamma ELISPOT.

RESULTThe novel DNA vaccine candidate could effectively express in vitro, boost with single intradermal injection of HBV DNA vaccine via EP can significantly enhance the surface antigen (S)-specific cellular immune responses (IFN-gamma ELISpot analysis) and PreS1-specific antibody levels, especially in the group primed with protein vaccine in combination with alum adjuvant.

CONCLUSIONBoost with the novel HBV DNA vaccine followed prime with HBV protein vaccine could induced a higher anti-HBV T cell response in mice than vaccination with the HBSS1 particle-like protein vaccine only. This prime-boost vaccination may serve as a promising way to develop and optimize the novel HBV therapeutic vaccine.

Animals ; Blotting, Western ; CHO Cells ; Cell Line ; Cricetinae ; Cricetulus ; Electroporation ; Enzyme-Linked Immunospot Assay ; Female ; Hepatitis B Vaccines ; immunology ; Hepatitis B virus ; immunology ; Humans ; Immunity, Cellular ; immunology ; Mice ; Mice, Inbred BALB C ; Vaccines, DNA ; immunology

OBJECTIVETo evaluate the application of (18)F-FDG PET/CT in diagnosis of classic fever of unknown origin.

METHODSA total of 27 consecutive patients with classic fever of unknown origin (FUO) (19 men, 8 women; aged 24-82 y) underwent (18)F-FDG PET/CT scans. The images were interpreted by visual inspection and semiquantitative analysis(standardized uptake value, SUV). Final diagnosis was based on histopathology or clinical follow-up.

RESULTSThe cause of FUO was confirmed by followed investigations in 21 of 27 cases after PET/CT scan, including 10 cases of infection, 4 of noninfectious inflammation, 4 of malignancies and 3 of miscellaneous disorders; and remaining 6 cases were still confirmed FUO. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 100.0 %, 83.3%, 83.3%, 100.0% and 96.3%, respectively.

CONCLUSIONFor patients with fever of unknown origin, (18)F-FDG-PET/CT can be a sensitive, reliable imaging modality. It is suggested that (18)F-FDG-PET/CT should be considered earlier in detecting the causes of FUO, which is difficultly diagnosed by conventional modalities.

Adult ; Aged ; Aged, 80 and over ; Diagnosis, Differential ; Female ; Fever of Unknown Origin ; diagnosis ; diagnostic imaging ; etiology ; Fluorodeoxyglucose F18 ; Humans ; Male ; Middle Aged ; Positron-Emission Tomography ; methods ; Radiopharmaceuticals ; Tomography, X-Ray Computed ; methods ; Young Adult

OBJECTIVETo determine the antigen characteristics of different fragments of SARS-CoV N protein expressed in E. Coli and their application in the serological diagnosis.

METHODSBased on preliminary analysis of 39 different segments of the N protein, We choosed six purified N protein for further antigenicity characterization in this study, including that PN360 (1 -360aa), PN301 (1-301aa), PN199 (30-228aa), PN185 (30-214aa), PN155b (60-214aa), and PN125 (90-214aa). We developed Western-Bolt and ELISA to detect antibody reactivity between truncated N fragments with sera from SARS-CoV-negative normal adults or SARS-CoV patient convalescent sera.

RESULTSWestern-Bolt results show that all the six fragments have reacted with the SARS patient convalescent sera, but the PN360 and PN301 showed obvious cross-reaction with sera from SARS-CoV-negative normal adults; sensitivity analysis using an ELISA coating with PN199, PN185, PN155b, PN125 as antigen showed that the PN185 and PN155b are better than PN125.

CONCLUSIONTruncated N protein PN185 and PN155b expressed in E. Coli are better antigen candidates used for detection of SARS-CoV specific antibody.

Antibodies, Viral ; blood ; Blotting, Western ; Enzyme-Linked Immunosorbent Assay ; Escherichia coli ; genetics ; Humans ; Nucleocapsid Proteins ; immunology ; Peptide Fragments ; immunology ; Recombinant Proteins ; immunology ; Serologic Tests ; Severe Acute Respiratory Syndrome ; diagnosis

To study IgG antibody persistence and temporal change in SARS coronavirus (SARS-CoV) infected patients, 22 patients recovered from SARS in Beijing were recruited and followed-up from 2004 to 2008, serum samples from patients were collected every year. We checked and analyzed the SARS-CoV IgG antibody (Ab) for five consecutive years using the commercial ELISA test kit. The results showed that: all of the serum were SARS-IgG antibody-positive the first year after recovery, the titer of most serum remained at high levels at the 2ed and 3rd year post infection. The Ab titers significantly declined at 4th year post infection. The IgG Ab was almost undetectable after 5 years post infection. In conclusion, SARS-CoV IgG Ab can be maintained for more than 3 years post infection, however, the titer of IgG Ab has declined markedly 4 years later. These data provide a useful reference for diagnosis and control of SARS infection, the evaluation of immune response and vaccine efficacy.
Adult ; Antibodies, Viral ; blood ; immunology ; Female ; Follow-Up Studies ; Humans ; Immunoglobulin G ; blood ; immunology ; Male ; Middle Aged ; SARS Virus ; immunology ; Severe Acute Respiratory Syndrome ; blood ; immunology ; virology

To investigate the seasonal influenza split vaccine's immune protective effectiveness against the homologous and heterogonous subtypes of influenza A virus challenge and the relationship between the protective effectiveness and hemagglutination inhibition (HI) antibody titer in mice. Two components of H1N1 and H3N2 in Chinese 2008-2009 seasonal influenza spilt vaccine, were derived from vaccine strain A/Brisbane/59/2007 (H1N1)-like virus and A/Brisbane/10/2007 (H3N2)-like virus respectively, and were used to immune BALB/c mice. Firstly, different doses of the vaccines were used to immunize mice and the HA immunization dosage that can induce the HI antibody titer of 40 in mice was identified; Secondly, H1N1 vaccine immunized mice were challenged with different doses of influenza virus mouse adaptation strains of A/Brisbane/59/2007 (H1N1)-like virus (MA) (referred to as A1 virus, well matched-strain in the homologous subtype) and A/Purto Rico/8/34 (H1N1) (referred to as PR8 virus, poor matched-strain in the homologous subtype) respectively, and H3N2 vaccine immunized mice were challenged with H1N1 influenza virus of A1 strain (Heterogonous subtype), body weight changes and survival rates were observed to explore the immune protective effectiveness of influenza split vaccine against the homologous and heterogonous subtypes of influenza A virus in mice. Results indicated that HI antibody titers were elevated as the HA protein immunization dosages increased from 0.15 microg, 0.5 microg, 1.5 microg, 5 microg to 15 microg in mice, and 1.5 microg HA of the seasonal influenza split vaccine could induced HI antibody titer of 40 in mice; 3LD50, 10LD50, 30LD50, 100LD50, 300LD50,1000LD50 and 3000LD50 of influenza virus strain A1 were used to challenge the H1N1 immunization mice, 1.5 microg HA of H1N1 vaccine could 100% protect mice against challenge with 1000LD50 of matched and homologous subtype of influenza virus strains A1, mice immunized with 15 microg HA of H1N1 vaccine even could 100% protect mice against challenge with 3000LD50 of influenza virus strains A1; but mice immunized with both the 1.5 microg and 15 microg HA of H1N1 vaccine were all sacrificed when challenged with 3LD50 of the mismatched and homologous subtype of influenza virus strain PR8, and mice immunized with the high dosage of 15 microg HA of H3N2 vaccine also were all sacrificed when challenged with 3LD50 of the heterogonous subtype of influenza virus strain A1. These results suggest that 1.5 microg HA of seasonal influenza split vaccine could induced HI antibody titer of 40 after one dose in mice, this dosage of HA can effectively protect mice against matched homologous subtype of influenza virus strain, but hardly to protect mice against mismatched homologous or heterogonous subtype of influenza virus strain. These results provide materials for the establishment of influenza vaccine evaluation system based on seasonal influenza vaccine.
Animals ; Antibodies, Viral ; blood ; Cells, Cultured ; Chick Embryo ; Dogs ; Female ; Influenza A Virus, H1N1 Subtype ; immunology ; Influenza Vaccines ; immunology ; Mice ; Mice, Inbred BALB C ; Orthomyxoviridae Infections ; prevention & control ; Vaccination

To efficiently express nucleoprotein (NP) of influenza A virus A/Jingke/30/95 (H3N2) in E. coli for further immunogenicity study, three forms of NP gene, NP(His) (NP fused with 6 x His tag), NPwt (wild type NP, non-fused NP with native codon) and NP(O) (codon optimized, non-fused NP) were cloned by the technologies of restriction enzyme digestion, PCR, codon optimization and gene synthesis. Three recombinant plasmids were subsequently constructed based on the prokaryotic vector pET-30a, respectively. The comparative studies with these plasmids were carried out on the gene expression efficiency, induction temperature and time, purification process and immune reactivity. It was confirmed by restriction enzyme digestion and sequencing analysis that the three NP genes were inserted into the expression plasmid pET-30a correctly. SDS-PAGE showed that all three forms of NP gene could be efficiently ex pressed in E. coli, among which NP(O) was expressed with the highest expression level. The lower temperature fermentation (T=25 degrees C) and longer time induction (t=10 h) were necessary for high-level expression of protein in soluble form. The purity of tag-free NP was up to 90% through the two-step purification process with anion-exchange and gel filtration chromatography. It was indicated by Western blot that purified NP reacted well with the serum from mice immunized with PR8 virus. These results suggest that the codon-optimized influenza A virus NP gene can be efficiently expressed in E. coli and the expressed NP protein with specific immune reactivity could be purified from the supernatant of bacterial lysate.
Animals ; Cloning, Molecular ; Escherichia coli ; genetics ; metabolism ; Gene Expression ; Humans ; RNA-Binding Proteins ; chemistry ; genetics ; isolation & purification ; metabolism ; Solubility ; Viral Core Proteins ; chemistry ; genetics ; isolation & purification ; metabolism