Objective To develop an effective and broad immune protective vaccination strategy by using DNA and recombinant vaccinia-based H5N1 vaccines.Methods BALB/c mice were immunized with various prime-boost regimens by using different DNA ( pIRES-based or pVRC-based) and recombinant vaccinia (Tiantan strain, rTTV)-based H5N1 vaccines expressing multivalent antigens (HA, NA, M1 and M2).The differences of immunity induced by two DNA vaccines were compared between intradermal electro -poration (IDE) and intramuscular electroporation (IME) deliveries.Immune responses were analyzed by hemagglutination inhibition( HAI) assay, neuraminidase ( NA)-specific antibody measured by ELISA , mi-croneutralization assay and IFN-γELISPOT assay .Results High levels of humoral immunity and T cell re -sponses were induced in mice primed with DNA-based vaccine than those primed with rTTVb-ased vaccine . DNA priming by IDE resulted in higher levels of neutralizing antibody in mice than those by IME delivery . Higher levels of HAI and anti-NA antibodies as well as NA-specific T cell responses were induced by pVRC-based DNA prime than those by pIRES-based DNA prime .HA-specific T cell responses were also enhanced in mice primed with pVRC-based DNA than those primed with pIRES-based DNA by IME .Conclusion The prime-boost strategies by using DNA-based vaccine in combination with rTTV-based H5N1 vaccine could induce humoral and T cell responses in mice against multi-antigens .Immunities induced by vaccines in com-bination might be modulated by various prime regimes .The study provided references for the further develop-ment of novel H5N1 vaccine and the optimization of immunization programs of combined multi-antigen vac-cine candidates .

Objective To investigate the possibility of using well-differentiated human airway epithelial cells (HAE) to isolate and identify human influenza A virus from a stale respiratory tract specimen.Methods The stale specimen used in this study was a nasopharyngeal swab specimen collected from a patient with unexplained pneumonia in Qinghai in 2010.It was positive for influenza A virus (H3N2) RNA, but negative for hemagglutination.Equal amount of the specimen was inoculated on HAE and on Madin-Darby canine kidney (MDCK) cells for virus isolation and passage.Cytopathic effects were observed daily after inoculation.Hemagglutination inhibition test was performed at every passage.Electron microscope was used to observe viral morphology.Viral genome was sequenced, followed by molecular evolutionary analysis.Results No progeny virus was isolated in MDCK cells, while a influenza A virus subtype H3N2 strain [A/Qinghai/178/2010(H3N2)] was isolated in HAE with a typical morphology and cytopathic effect of influenza A infection.The hemagglutination inhibition activity was 1∶16.Results of the molecular evolutionary analysis of viral genome showed that the influenza A virus (H3N2) strain was highly homologous to the A/Nanjing/1655/2010(H3N2) strain, which was isolated during the 2010 influenza pandemic in Nanjing.Conclusion HAE can be used for isolation and identification of virus from stale respiratory tract specimens.It is more sensitive than MDCK cells with regard to human influenza virus isolation.

Data based on the antiviral-resistant phenotyping characteristics of 884 influenza B viruses circulating in mainland China from October 2013 to March 2014 were analyzed to assess the susceptibility of influenza B viruses to neuraminidase inhibitors. All 884 viruses were sensitive to oseltamivir; two viruses (0.23%) had reduced sensitivity to zanamivir and all other viruses were sensitive to zanamivir. Among the 38 viruses with a B/Victoria lineage, B/Shandong-Kuiwen/1195/2014 exhibited a half-maximal inhibitory concentration (IC50) for zanamivir that was elevated by 5. 12-fold (1.78 nM) compared with neuraminidase inhibitors sensitive to the reference virus (0.34 nM), suggesting that it exhibited reduced inhibition by zanamivir. D35G, N59D and S402T (39, 64 and 399 with N2 number) amino-acid substitutions in the NA gene were detected with no previously reported antiviral-resistant substitutions. Among viruses with the 846 B/Yamagata lineage, B/Hunan-Lingling/350/2013 exhibited a 7.99-fold elevated IC50 for zanamivir (2.72 nM) compared with neuraminidase inhibitors sensitive to the reference virus (0.34 nM), suggesting that it exhibited reduced inhibition by zanamivir. D197N (N2 number), a previously reported antiviral resistant-related amino-acid substitution in the NA gene, was detected in B/Hunan-Lingling/350/2013. These data suggest that recently circulating influenza B viruses in mainland China have retained susceptibility to neuraminidase inhibitors.
Amino Acid Substitution ; Antiviral Agents ; pharmacology ; China ; epidemiology ; Drug Resistance, Viral ; Enzyme Inhibitors ; pharmacology ; Humans ; Influenza B virus ; drug effects ; enzymology ; genetics ; isolation & purification ; Influenza, Human ; epidemiology ; virology ; Microbial Sensitivity Tests ; Neuraminidase ; antagonists & inhibitors ; genetics ; metabolism ; Viral Proteins ; antagonists & inhibitors ; genetics ; metabolism

Objective To analyze the phenotypic characteristics of antiviral-resistant influenza B viruses circulating in mainland China and to analyze the susceptibility of influenza B viruses to neuraminidase inhibitors ( NAIs) . Methods Antiviral-resistant phenotyping test was performed to analyze the NAI suscep-tibility of 1 386 influenza B viruses isolated in mainland China from April 2014 to March 2015, including the test of susceptibility to oseltamivir and zanamivir. Results All of the 94 B-Victoria lineage viruses were sensitive to oseltamivir and zanamivir. Of all 1 292 B-Yamagata lineage viruses tested, 1 virus showed re-duced sensitivity to oseltamivir with NA gene containing I221T amino acid mutation, 10 viruses showed re-duced sensitivity to zanamivir with 4 having D197N amino acid mutation in NA gene, 3 viruses showed re-duced sensitivity to both oseltamivir and zanamivir with NA gene possessing D197N amino acid mutation and 1 virus carrying the A245T amino acid mutation in NA gene showed reduced sensitivity to oseltamivir and highly reduced sensitivity to zanamivir. Conclusion The majority of influenza B viruses circulating in main-land China during 2014 to 2015 were sensitive to NAIs, which indicated that NAIs could be used continually for clinical treatment of patients with influenza. Sustained monitoring of antiviral susceptibility of influenza B viruses should be emphasized for timely detection of antiviral resistant viruses and more attention should be paid to the D197N mutations in NA gene of influenza B viruses.

Objective To develop an effective and broad immune protective H5N1 vaccine.Methods We first developed two recombinant vaccinia ( Tiantan strain) virus ( rTTV ) based H5N1 vaccines, which consisted of bicistron expressing the hemagglutinin(HA) and matrix protein 2(M2), or bicistron expressing the neuraminidase(NA) and matrix protein 1 (M1). The expression of H5N1 protein in rTTVs was confirmed. We immunized the BALB/c mice twice with two kind of dose ( 104 PFU, 107 PFU)using different combination. Subsequently, we assessed the humoral and cellular immune response in vaccinated mice. Results Our data showed that rTTV-based H5N1 vaccine induced rapidly robust HA- and NAspecific antibody level and IFN-γ secreting form cell(SFC) with either single dose of 107 PFU or twice dose of 104 PFU or 107 PFU. We also detected significant neutralizing antibody and matrix-specific immune response. In addition, we found that immunization with two kind of rTTV-based H5N1 vaccines induced much high level of M2-specific antibody than that with single of rTTV-based H5N1 vaccine. Conclusion rTTVbased H5N1 vaccines in this study elicited board array of immunity and our study offers a promising alternative H5N1 vaccine candidates with favorable potential to prevent various H5N1 pandemic.

To analyze the antigenic and genetic characteristics of the influenza A (H3N2) virus in mainland China during the surveillance year of 2013-2014, the antigenic characteristics of H3N2 virus were analyzed using reference ferret anti-sera. The nucleotide sequences of the viruses were determined by Sanger dideoxy sequencing, phylogenetic trees were constructed with the neighbor-joining method, and the genetic characteristics of the viruses were determined in comparison to current vaccine strains. The results showed that most of the H3N2 viruses were antigenically closely related to the A/Victoria/361/2011 vaccine strain cell-propagated prototype virus (99.6%). Using the A/Texas/50/2012 egg isolate as the reference antigen, 15.1% of the viruses were found to be closely antigenically related to it, while 11.9% of strains were closely antigenically related to the egg-propagated epidemic strain, A/Shanghai-Changning/1507/2012. Phylogenetic analysis of HA genes indicated that the A(H3N2) viruses in this surveillance year were in the same clade, but no drug resistant mutation was identified in the NA genes. During the 2013-2014 influenza surveillance year, no significant genetic change was detected in either the HA or NA genes of the A(H3N2) viruses, while significant mutations were found in egg isolates resulting from their adaptation during propagation in eggs. The antigenic and genetic changes should be investigated in a timely manner to enable the selection of an appropriate vaccine strain in China.
Animals ; Antigenic Variation ; Base Sequence ; Chick Embryo ; China ; Genetic Variation ; Hemagglutinin Glycoproteins, Influenza Virus ; genetics ; immunology ; Humans ; Influenza A Virus, H3N2 Subtype ; genetics ; immunology ; isolation & purification ; Influenza, Human ; virology ; Molecular Sequence Data ; Mutation ; Phylogeny

Objective To analyze the causes,cardiac function grading and drug application related to heart failure of the patients with chronic heart failure in Yongchuan district people's hospital.Methods The cases of chronic heart failure of department of cardiology in our hospital from January 1st,2012 to December 31st,2015 were counted and retrospectively analyzed.Results 3 320 cases of chronic heart failure in our hospital chosen from 8 126 medical records accounted for 40.86% of total discharged patients in the same period,including 2 262 cases of coronary disease (68.13%),353 cases of rheumatic heart disease (10.63%)and 265 cases of pulmonary heart disease (7.98%),who took up the top three in the spectrum of disease;2 683 cases of NYHA heart function Ⅲ magnitude accounted for 80.81%;The utilization rate of diuretic,digoxin,spironolactone,angiotensin -converting enzyme inhibi-tor,angiotonin receptor blocker,beta adrenergic receptor were 71.23%,27.23%,70.48%,30.75%,30.78%respectively.The statistical analysis showed that the differences were statistically significant between the patients using diuretics and the patients using spirolactone(χ2 =2.386,P <0.001),the patients with hypertension and the patients with no hypertension using ACEI /ARB(χ2 =2.727,P <0.001),and merged chronic bronchitis patients and the chro-nic bronchitis patients using beta -blocker(χ2 =61.807,P <0.001).Conclusion The patients with chronic heart failure takes up a higher portion among the inpatients in department of cardiology in the district level hospital.The heart function decreases significantly and the normative drug therapy needs to be improved.

Objective To investigate the changes in the structural parameters and mechanical properties of the necrotic femoral head and compare the effects of core decompression and hone grafting with those of bone cement filling on the mechanical properties and pre-vention of articular surface collapse of the necrotic femoral head.Methods Thirty-two fresh human femoral heads were collected from patients who underwent total hip arthroplasty at our hospital between June 2020 and January 2022.The femoral heads were divided into four groups:8 femoral neck fractures(TFF group),8 osteonecrosis of the femoral head(ONFH group),8 osteonecrosis of the femoral head treated with cement percutaneous injection(CPI group),and 8 osteonecrosis of the femoral head treated with core decompression and bone graft(CDBG group).Cement filling or core decompression was performed under radiographic guidance.All samples were scanned and three-dimensionally reconstructed using micro-CT.The spatial heterogeneity of the femoral head was observed,and the bone morphometric parameters of each region of interest were calculated.Mechanical analysis was performed to evaluate the femoral head parameters of dis-placement and stress in vitro.Results Bone microarchitecture and morphometry in necrotic femoral heads were markedly altered.The biomechanical properties of the necrotic zone in the femoral head were markedly weakened.After the necrotic area was filled with bone cement,the biomechanical properties of the necrotic zone of the femoral head increased significantly.In addition,after core decompres-sion and bone grafting in the necrotic area,the biomechanical properties increased significantly in the necrotic zone of the femoral head.Conclusion Bone cement filling or bone grafting in the necrotic area can change the biomechanical mechanism of the femoral head,improve the load-supporting ability,and prevent femoral head collapse.Cement filling may be a practical approach for the treatment of osteonecrosis of the femoral head that can be useful for practicing orthopedists.

OBJECTIVETo analyze the susceptibility of influenza A (H3N2) viruses to neuraminidase inhibitors during 2011-2012 in Mainland China.

METHODSAll the tested viruses were obtained from the Chinese National Influenza Surveillance Network, which covers 31 provinces in mainland China, including 408 network laboratories and 554 sentinel hospitals. In total 1 903 viruses were selected with isolation date from January 1, 2011 to December 31, 2012 in Mainland China, among these viruses, 721 were confirmed to be influenza A (H3N2) virus by Chinese National Influenza Center and tested for the susceptibility to oseltamivir and zanamivir using chemiluminescence-based assay. The neuraminidase inhibitor sensitive reference virus A/Washington/01/2007 (119E) and oseltamivir resistant virus A/Texas/12/2007 (E119V) were used as control in this study. The t -test was used to compare the difference of NAI susceptibility of viruses isolated from different years.

RESULTSThe half maximal inhibitory concentration (IC₅₀) of A/Washington/01/2007 for oseltamivir and zanamivir was (0.10 ± 0.02) and (0.30 ± 0.05) nmol/L, respectively. The IC₅₀ of A/Texas/12/2007 for oseltamivir and zanamivir was (4.27 ± 1.60) and (0.20 ± 0.03) nmol/L, respectively. Among the 721 influenza A (H3N2) viruses, 132 influenza A (H3N2) viruses were isolated in 2011 and 589 influenza A (H3N2) viruses were isolated in 2012. The IC50 for oseltamivir ranged from 0.04 to 0.62 nmol/L for viruses isolated in 2011 and ranged from 0.02 to 0.95 nmol/L for viruses in 2012, and the IC₅₀ of all the viruses tested was within 10-fold IC₅₀ (1.0 nmol/L) of the neuraminidase inhibitor sensitive reference virus A/Washington/01/2007. The IC50 of zanamivir ranged from 0.12 to 0.80 nmol/L for viruses in 2011 and ranged from 0.04 to 0.72 nmol/L for viruses in 2012, and was within 10-fold IC₅₀ (3.0 nmol/L) of the neuraminidase inhibitor sensitive reference virus A/Washington/01/2007.

CONCLUSIONThe influenza A(H3N2) viruses isolated during 2011-2012 in Mainland China were tested to be sensitive to oseltamivir and zanamivir.

Antiviral Agents ; China ; Drug Resistance, Viral ; Enzyme Inhibitors ; Epidemiological Monitoring ; Humans ; Influenza A Virus, H3N2 Subtype ; Influenza, Human ; Neuraminidase ; Oseltamivir ; Zanamivir