Objective To investigate the effect of recombinant human interferon α-2b on influenza virus in vitro.Methods Influenza A virus subtype H1N1 and influenza B/Y virus were inoculated into Vero cells and different concentrations of interferon α-2b and oseltamivir were added.Numbers of virus plaques were observed and calculated,and quantitative RT-PCR were used to assess the inhibitory effect of interferon α-2b and oseltamivir in vitro.The nuclear export of viral ribonucleoprotein (RNP) complexes were monitored under fluorescence microscope.Results Virus plaque test showed that influenza A viruses subtype H1N1 were significantly inhibited when 10 μg/μL interferon α-2b and 10 μg/μL oseltamivir were added,and the numbers of plaques were 7.5 × 108 and 15 × 108 PFU/mL,respectively;the inhibitory effect of oseltamivir was better than that of interferon α-2b.Influenza B/Y viruses were also inhibited when 10 μg/μL interferon α-2b and 10 μg/μL oseltamivir were added,and the numbers of plaques were 1.1 × 108 and 1.5 × 108 PFU/mL,respectively.Quantitative RT-PCR results showed that the cycle threshold (CT) values of influenza A virus subtype H1N1 and influenza B/Y virus were much higher when 10 μmol/L interferon α-2b and 10 μmol/L oseltamivir were added.CT values of influenza A virus subtype H1N1 were 16,26 and 35 before and after inferferon α-2b and oseltamivir were added.CT values of influenza B/Y virus were 18,27 and 31 before and after interferon α-2b and oseltamivir were added.Reduction in the nuclear export of viral RNP in influenza A virus subtype H1N1-infected Vero cells was also observed when 10 μmol/L interferon α-2b were added.Conclusion Interferon α-2b has significantly inhibitory effect on both influenza A virus subtype H1N1 and influenza B/Y virus in vitro.

Objective : To prepare the gelatin methacryloyl(GelMA)/hydroxyapatite(HA) composite hydrogel scaffold by additive manufacturing(AM) technology, and to explore its feasibility as a scaffold for repairing in bone tissue engineering via characterizing microstructure and testing biocompatibility. Methods: The GelMA solution and hydroxyapatite particles were uniformly mixed to prepare a bio-ink firstly.Then, AM technology was used to fabricate the GelMA/HA composite hydrogel scaffold.The microstructure and components of the composite scaffold were characterized and analyzed by scanning electron microscope(SEM) and transmission electron microscope(TEM).The Young′s modulus of pure GelMA scaffold and the composite scaffold was measured by a mechanical tester.Cell counting kit-8(CCK-8) and Live/dead cell staining were used to evaluate the cytocompatibility of scaffolds.Alkaline phosphatase(ALP) staining was used to explore the osteogenic properties of scaffolds. Results : The GelMA/HA hydrogel scaffold showed a porous and lattice-like structure and exhibited stiffer than pure GelMA scaffold.The live-dead cell staining experiment exhibited that BMSCs grew well and displayed a spread morphology on the composite scaffold after 7 days of culture.Cell proliferation experiments showed that the proliferation rates of BMSCs in pure GelMA hydrogel scaffold group and the GelMA/HA composite hydrogel scaffold group cultured for 3 and 7 d were higher than those of the blank group(P<0.05).The ALP staining experiment revealed that the positive ALP stained area of the GelMA/HA composite hydrogel scaffold significantly increased(P<0.05) compared with the blank group and pure GelMA hydrogel scaffold group. Conclusion The GelMA/HA composite hydrogel scaffold processes good biocompatibility and promotes the osteogenic differentiation of BMSCs, which has a potential to be used as a filling and repair scaffold for bone tissue engineering.

Objective:To evaluate the safety and feasibility of the laparoscopic indocyanine green (ICG) fluorescence imaging during the sentinel node navigational surgery for the early gastric cancer.Methods:Patients with <4 cm early gastric cancer were chosen. 0.5 ml ICG (2.5 mg/ml) was preoperatively injected into submucosa around the lesion in four points by the endoscopy. The sentinel lymph node basin including the stained tissue and lymph node (LN) were completely resected guided by the fluorescence mapping under ICG laparoscopy. The specimen was inspected by frozen pathology section. The radical gastrectomy was dependent on the pathology result.Result:Between 2019 and 2021, a total of 18 patients were included in the final analysis. Most tumors (16/18) located in the middle or distal stomach. Median tumor size was 2.0 cm. Lymph vessel invasion was revealed in five cases and perineural invasion in three cases. According to AJCC tumor grading system, tumor depth was classified as Tis in 2 cases, T1a in 5 cases and T1b in 11 cases. Lymph node metastasis (LNM) was revealed in four patients (4/18, 22%). Median sentinel lymph node basins per patient were 2 (range, 1-5). An average 6 (range, 2-13) LNs were harvested in each case, including 6 (1-13) ICG stained LNs and 1 (0-5) non stained LNs. All of four LNM patients were detected by sentinel node navigational surgery. The rate of the sensitivity and accuracy were 100% and 100%, respectively. The median follow-up for the entire group was 58.3 months (0.3-59.9 months), with no recurrence or metastasis observed in any patient.Conclusion:The sensitivity and accuracy of the laparoscopic indocyanine green fluorescence imaging during the sentinel node navigational surgery were satisfactory.

Objective : By testing the tensile strength of the poly(vinyl alcohol) (PVA)/bacterial cellulose(BC) composite membrane and its effect on the proliferation of mouse embryonic fibroblasts, its potential as new bone tissue engineering membrane were studied. Methods : PVA⁃BC films of different proportions and pure PVA films were prepared by self⁃evaporation method. The tensile strength of each group was tested. The group with the highest tensile strength was immersed in deionized water for 0. 5 h to measure its wet tensile strength. The microstructure of pure PVA film and the film with the highest tensile strength was observed by scanning electron microscopy (SEM) .X⁃ray diffraction and Fourier transform infrared ( FTIR) spectroscopy were used to analyze pure PVA, pure BC,and the film with the highest tensile strength respectively. Cell counting kit⁃8 (CCK⁃8) was applied to detect the survival rate in the blank control group, the pure PVA film group, and the composite film group with the highest tensile strength. Results : PVA⁃BC composite films were successfully prepared, X⁃ray diffraction and FTIR analysis revealed the co⁃presence of PVA and bacterial cellulose in the composite film. The initial tensile strength of the composite membrane increased with the BC ratio. When the concentration ratio of PVA to BC was 10 ∶ 7, the tensile strength reached (155. 5 ± 14. 7) MPa, and wet samples reached (13. 8 ± 1. 2) MPa. The CCK⁃8 test of NIH/3T3 showed that there was no significant difference among the PVA⁃BC composite film group, pure PVA group and blank control group after 1,4 and 7 days of cell culture ( P > 0. 05 ) . Conclusion PVA⁃BC film fabricated by blending method obtain certain mechanical properties and biocompatibility in both wet and dry states, which may be an appropriate candidate as a GBR membranes for clinical application.