Hemagglutinin (HA) contains a head domain with a high degree of variability and a relatively conserved stem region. HA is the major viral antigen on the surface of the influenza virus. To define the biologic activities of chimeric HA bearing different head domains and stem regions or their potential use, a HA chimeric gene containing the head domain of the H7 subtype virus and stem region of the H3 subtype virus was modified and expressed using a baculovirus expression vector. Then, the secreted protein was purified and its biologic activities characterized. Approximately 1.4 mg/mL cH7/3 HA could be obtained, and its molecular weight was ≈ 70 kD. The trimer form of cH7/3 protein had hemagglutination activity and could be recognized by specific antibodies. The method described here can be used for further studies on the screening of HA stem-reactive antibodies or the development of vaccines with conserved epitopes.
Antibodies, Viral ; immunology ; Baculoviridae ; genetics ; metabolism ; Gene Expression ; Genetic Vectors ; genetics ; metabolism ; Hemagglutination ; Hemagglutinin Glycoproteins, Influenza Virus ; genetics ; immunology ; Humans ; Influenza Vaccines ; genetics ; immunology ; Influenza, Human ; prevention & control ; virology

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Objective To study the effect of curcumin on the radiosensitivity of the human papillary thyroid cancer cell line TPC?1, to investigate the signaling pathway probably targeted by curcumin, and to provide new insights for the development of radiosensitizers for thyroid cancer. Methods The human papillary thyroid cancer cell line TPC?1 was treated with curcumin and radioactive iodine. CCK?8 assay, colony formation assay, and flow cytometry were used to evaluate cell proliferation, colony formation ability, and cell apoptosis, respectively. Western blot was used to measure the expression of p50, p65, and apoptosis?related proteins, Bcl?2 and Bax. Cell proliferation, colony formation ability, and cell apoptosis were determined again after the activity of the NF?κB signaling pathway was blocked by a NF?κB signaling pathway inhibitor PDTC. Results After treatment with curcumin and radioactive iodine, the human papillary thyroid cancer TPC?1 cells had reduced cell proliferation and colony formation, an elevated apoptosis rate, downregulated expression of anti?apoptotic Bcl?2, and upregulated expression of pro?apoptotic Bax in a dose?dependent manner. These results indicated that curcumin enhanced the radiosensitivity of TPC?1 cells. Curcumin inhibited the activation of the NF?κB signaling pathway in the TPC?1 cells treated with radioactive iodine. When the activity of the NF?κB pathway was blocked by PDTC, cell proliferation and colony formation were reduced and the apoptosis rate was increased, indicating an enhanced radiosensitivity of TPC?1 cells. Conclusions Curcumin is likely to target the NF?κB signaling pathway. It regulates the radiosensitivity of thyroid cancer cells by inhibiting the activity of the NF?κB signaling pathway.

To study the effects of three different laser treatments (650 nm alone, 10.6 μm alone and combined laser of 650 nm and 10.6 μm) on experimental osteoarthritis of the knees in C57 black mice.

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

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: This cross-sectional study explores the serial multiple mediation of the correlation between internet addiction and depression by social support and sleep quality of college students during the COVID-19 epidemic. Methods: We enrolled 2,688 students from a certain university in Wuhu, China. Questionnaire measures of internet addiction, social support, sleep quality, depression and background characteristics were obtained. Results: The prevalence of depression, among 2,688 college students (median age [IQR]=20.49 [20.0, 21.0] years) was 30.6%. 32.4% of the students had the tendency of internet addiction, among which the proportion of mild, moderate and severe were 29.8%, 2.5% and 0.1%, respectively. In our normal internet users and internet addiction group, the incidence of depression was 22.6% and 47.2%, respectively. The findings indicated that internet addiction was directly related to college students’ depression and indirectly predicted students’ depression via the mediator of social support and sleep quality. The mediation effect of social support and sleep quality on the pathway from internet addiction to depression was 41.97% (direct effect: standardized estimate=0.177; total indirect effect: standardized estimate= 0.128). The proposed model fit the data well. Conclusion Social support and sleep quality may continuously mediate the link between internet addiction and depression. Therefore, the stronger the degree of internet addiction, the lower the individual’s sense of social support and the worse the quality of sleep, which will ultimately the higher the degree of depression. We recommend strengthening monitoring of internet use during the COVID-19 epidemic, increasing social support and improving sleep quality, so as to reduce the risk of depression for college students.

Objective: The purpose of this cross-sectional survey is to explore the current state of Internet addiction (IA) in Chinese medical students and its connection with medical students’ sleep quality and self-injury behavior. Methods: Respondents were came from Wannan Medical College, China. The Young’s Internet Addiction Test, Pittsburgh Sleep Quality Index (PSQI), Self-Harm Questionnaire were used in this cross-sectional survey. A total of 3,738 medical students were investigated, 1,552 (41.52%) males, 2,186 (58.48%) females. T-test, chi-square test and MANOVA were used for data analysis. Results: Of the 3,738 medical students, 1,054 (28.2%) reported having IA, 1,126 (30.1%) reported having poor sleep quality, 563 (15.1%) having self-harm behaviors. IA tends to be more female, upper grade students. The sleep quality of IA was worse than that of non-IA (χ2=54.882, p<0.001), and the possibility of self-injury was higher than non-IA (χ2=107.990, p<0.001). Conclusion This survey shows that the IA detection rate of medical students was 28.2%. Females, higher grade students had a higher IA detection rate. The low sleep quality and self-injury behavior of medical students are associated with IA.

Objective: To examine the status of self-harm, depression and anxiety and to analyze the relation of self-harm with depression and anxiety in college students. Methods: Totally 9 638 college students were randomly selected from five universities in Anhui province using stratified cluster sampling and were surveyed with basic demographic characteristics, Depression Self Rating Scale (SDS), Self-evaluation of Anxiety Scale (SAS) and self-harm behavior questionnaire. Results: The detection rate of self-harm among college students was 22.94%(2 211), boys (24.51%) were higher than girls(21.72%), the difference was statistically significant(χ2=10.46, P<0.05). The detection rate of depression was 28.57%(2 754). The detection rate of anxiety was 11.11%(1 071). The detection rate of self-harm in the depression group was 33.48%, which was significantly higher than those without depression group(18.72%)(χ2=242.22, P<0.01). The similar results were found in the anxiety analysis, students with anxiety showed higher detection rate in self-harm (48.74%) than those without anxiety (19.72%)(χ2=453.66, P<0.01). Both depression and anxiety were positively associated with self-harm behaviors(r=0.24, 0.27, P<0.01). Multivariate Logistic regression model found that after covariates controlled, depression(OR=1.48) and anxiety (OR=2.84) were positively associated with self-harm of college students(P<0.05). Conclusion Self-harm, depression and anxiety among college students in Anhui Province are at a high level, and a positive correlation between self-harm behaviors and depression and anxiety is observed. Attention should be paid to the mental health education of college students.