Objective To investigate the effects of exposure to various concentrations of cigar smoke on gut microbiota in mice.Methods A total of 40 C57BL/6 mice were randomly divided into the control group,the low-dose cigar exposure group,the medium-dose group and the high-dose group,with 10 mice in each group.After 4 weeks of feeding,fecal samples were collected for gene sequencing of 16S ribosomal RNA and analysis of differences in gut microbiota.Results Compared to the control group,gut microbiota richness was signifi-cantly reduced in the cigar-exposed groups(P<0.05).Compared with thecontrol group,the Shannon index of mice in the high-dose group was significantly increased(P<0.05).In multi-group comparisons,ten bacterial genera with high abundance-such as Akkermansia,Allobaculum,and Alloprevotella-were identified.Pairwise comparison results indicated that compared to the control group,abundances of Akkermansia,Candidatus_Sac-charimonas,and Lactobacillus decreased while those of Allobaculum,Alloprevotella,Muribaculaceae,and Pre-votellaceae_UCG001 increased(P<0.05).Alistipes and Faecalibaculum showed significant increases in low-dose and medium-dose groups respectively,Blautia and Lachnospiraceae_NK4A136 group exhibited notable in-creases in the high-dose group(P<0.05).Linear discriminant analysis effect size revealed that six phyla and forty-four species displayed significant differences across all groups at both phylum and species levels,distinct dose-specific were observed among different cigar exposure groups.Conclusion Cigar smoke exposure and different exposure concentrations can both cause changes in the gut microbiota.The effects of different con-centrations of cigars on the gut microbiota of mice are specific.

Objective:To analyze the genetic and molecular characteristics of H9N2 subtype avian influenza viruses from external environment and humans in Anhui Province from 2013 to 2022.Methods:Environmental samples and human samples were collected from Anhui influenza surveillance network laboratory. Sixty-three strains of virus were isolated in chicken embryos. RT-PCR was used to amplify the virus and whole genome sequencing was performed. To construct gene evolutionary tree and analyze its genetic characteristics and potential glycosylation sites.Results:The hemagglutinin (HA) gene belongs to the 9.2.4.5 clade, and the protein cleavage sites are mostly " PSRSSR\GL". The neuraminidase (NA) gene, basic protein-1(PB1) gene, acidic protein (PA) gene, non-structural protein (NS) gene and nucleoprotein (NP) gene belong to the F/98 clade, the matrix protein (MP) gene belongs to the G1/97 clade, and the basic protein-2 (PB2) gene belongs to the ST/7488 clade. Mutations of T155N, R164Q, H183N, T189D/V, A190V/T and Q226L occurred in HA protein, deletion of NA protein occurred at 62-64 sites, and mutations of T271A, I292V/M and E627V/L occurred in PB2 protein. At the same time, mutations of K356R and S409N occurred in the PA protein.Conclusions:The H9N2 subtype avian influenza viruses collected from external environment and human sources in Anhui province from 2013 to 2022 belong to the same evolutionary branch, and amino acid site mutations suggest that the virus shows a tendency to gradually adapt to the mammalian host environment. Therefore, further studies on the adaptive evolution of the virus and related monitoring work are needed.

Objective:Analysis of the characteristics of influenza epidemic in Anhui Province and quantification of the impact of different factors on influenza occurrence, providing scientific basis for better influenza prevention and control.Methods:Descriptive analysis and factor analysis were conducted on influenza-like illness (ILI) cases and RT-PCR results in Anhui Province from 2013 to 2021 using data from China's Influenza Monitoring Information System.Results:The percentage of influenza-like illness (ILI%) of sentinel hospitals in Anhui Province from April 1, 2013 to March 31, 2021 was 3.80% (1 209 142/31 779 987), showing an overall increasing trend, with a relatively high proportion in 2017-2018 at 4.30% (191 148/4 448 211). The proportion of ILI cases in infants and young children aged 0-4 years was a relatively high at 54.14% (654 676/1 209 142), and the highest ILI% was observed in Fuyang City, Anhui Province (6.25%, 236 863/3 788 863). Laboratory monitoring results showed that the positive rate of ILI cases in sentinel hospitals in 8 influenza monitoring years was 16.38% (34 868/212 912), showing an increasing trend year by year, with a relatively proportion in 2017-2018 at 26.19% (6 936/26 488). The detection rate of school-age children aged 5-14 years was a relativelyhigh at 28.81% (13 869/48 144), and the positive rate was a relatively high in Wuhu City among the 16 cities, reaching 22.01% (2 693/122 237). Influenza activity showed a single peak in winter-spring and alternating double peaks in winter-spring and summer, with different subtypes alternating, and A (H3N2) was the dominant subtype in summer. The results of a multiple logistic regression model showed that the positive rate was higher in 2017-2018, among children aged 5-14 years, in winter, and in southern Anhui.Conclusions:Influenza epidemic in Anhui Province has a clear seasonal pattern, and the ILI% and detection rate have shown an upward trend from 2013 to 2021. Therefore, it is suggested to ensure vaccine supply before the winter-spring influenza season arrives, and to strengthen vaccine uptake and health education to avoid the risk of infection during the peak period of influenza.

Objective:To compare the differences between suspension and adherent cells of MDCK cell line in the isolation of influenza virus, and to explore the application prospects of MDCK cell suspension.Methods:Determination of viable cell density and cell specific growth rate were recorded by cell count. The WHO recommended vaccine strains were used for virus infection experiments. After five passages, hemagglutination titers were detected, while the sequencing analysis of their HA and NA genes revealed the mutation frequency.Results:The 24-hour and 48-hour viable cell density of the cell suspension was more stable than that of adherent cells. The cell suspension achieved an HA titer of 1∶256 or higher in the third generation, while adherent cells had no titer. In the fourth and fifth generations, one amino acid site mutation was found in the HA gene of H3N2 and BV subtypes of influenza virus cultured in the cell suspension, while no gene mutation was found in adherent cells in two passages. There were no mutations in the whole NA gene.Conclusions:Suspension of MDCK cells have more stable growth and higher efficiency in virus isolation than adherent cells, meanwhile there was a low rate of virus mutation during continuous passage. This study demonstrated the feasibility of this suspension of MDCK cells for influenza vaccine production based on cell culture technology.

Objective To explore the effect of the use of flap transplantation combined with Masquelet tech-nique in the repair of long bone accompanied with soft tissue defect. Methods The retrospective study includes 16 cases of bone defects over 6.0 cm combined with soft tissue defect from March,2013 to March,2016,13 males and 3 females, of which the ages range from 16 to 65 years. The length of bone defect ranged from 6.0 to 12.0 cm, with an average of 8.5 cm,while the wound defect ranged from 5.2 cm×3.5 cm to 16.0 cm×7.5 cm. There were 8 cases out of 16 involve an infection:3 cases of Staphylococcus aureus(including 1 MRSA),2 cases of Staphylococcus epidermidis, 2 cases of Enterobacter cloacae, and 1 case of Acinetobacter baumannii. The 1 stage surgery in all patients admitted to hospital after complete debridement and external fixation, the clean wounds with bone defect received antibiotic-impregnated bone cement filling operation and a flap transplantation or transposition directly after the debridement, but the infected wounds received vacuum sealing drainage treatment firstly, associated with adequate use of antibi-otics for 1-2 weeks and then the bone cement filling and flap transplantation with infection totally controlled.After 8-12 weeks, we conducted the secondary internal fixation surgery replacing antibiotic-impregnated bone cement with autogenic cancellous bone, vancomycin artificial bone as well as rhBMP-2. All the cases were followed for 6 to 18 months. Results All patients with primary surgery are effectively controlled after 1-4 weeks of anti-infection treat-ment exclusive of the case with MRSA.As the condition of the patient with MRSA relapse,we changed to convention-al treatment: placed a continuous irrigation and suction equipment instead of the bone cement filling, the wound healed completely without fistula formation of osteomyelitis in 6 months after the treatment of Ilizarov technique. All transplantation and transposition flaps survived. As for those who received a secondary bone graft operation, all achieved a bony union in a period of 4-6 months. Conclusion The combination of flap transplantation and Masquelet technique is an effective method to repair limb long bone and soft tissue defect currently.

Objective To establish Ad-hLIF transgenic feeder cells for the expansion of umbilical cord blood CD34+ HSPC in vitro and study the SCID mice model of hematopoietic stem/progenitor cell (HSPC) transplantation. Methods The expression of objective gene in Ad-hLIF transgenic feeder cells was detected by RT-PCR and ELISA. The purity of umbilical cord blood CD34+ HSPC separated by magnetic-activated cell sorting(MACS) was detected by the flow cytometry. After expanded with various combinant of cytokines and transgenic feeder layer cells for 28 d, the quantity of mono-nuclear cell (MNC) and CD34+ cells rate was detected in different time. MNC after expansion stained by CFDA SE was injected to the sublethally irradiated SCID mice. Humanize gene Alu was detected by RT-PCR and fluorescence microscope. Results The green fluorescence was observed in the transgenic cells infected with 50MOI( multiplicity of infection) Ad-hLIF, and the objective gene was confirmed by RT-PCR and ELISA. The purity of umbilical cord blood CD34+ HSPC separated by MACS could reach 95.60% ±2.58%, Ad-hLIF transgenic feeder cells and various cytokines system increased MNC by 356.95±0.87 fold, and maximal expansion of CD34+ cells was observed during 0-14 d of culture, then down-expansion gradually. Four weeks after transplanted in SCID mice, fluorescently-labeled humanize cells still can be observed. The existence of the humanized gene Alu was confirmed by RT-PCR. Conclusion Ad-hLIF transgenic feeder cells can effectively proliferate umbilical cord blood CD34+ HSPC in vitro and delay it differentiate, what's more, it has high transplant efficacy and haematogenesis activity.