[Evaluation of influenza vaccine effectiveness in 2017-2018 influenza season based on community children cohort study].

Objective: To assess the effectiveness of influenza vaccine in children aged 6-72 months. Methods: The cohort study was conducted based on community child vaccination clinics in Yiwu and Yongkang counties of Zhejiang province. From October 2017 to December 2017, a total of 1 752 children aged 6-72 months were enrolled from 10 child vaccination clinics. The questionnaire survey was conducted after the written consents were obtained from the parents or legal guardians of the children. Then, a follow up was conducted for enrolle children until 30 April 2018, the influenza vaccination status and the number of influenza-like illness (ILI) cases, hospital visit due to ILI, self-medication due to ILI were observed and recorded every month. Vaccine effectiveness (VE) was estimated by using the generalized linear model (GLM) where dependent variables were the number of ILI cases, hospital visit and self-medication respectively. Results: Of the 1 752 children, 925 (52.80%) were boys and the median age was 30.00 months. The cumulative observation was 308 166 person days at the end of 2017-2018 season, with 5.27 ILI cases per 1 000 person days, 3.41 hospital visit due to ILI per 1 000 person days, 1.45 self-medication due to ILI per 1 000 person days. Of the 1 752 children, 643 received the influenza vaccination in 2017-2018 season. Compared with unvaccinated children, the VE was 23.5% against ILI case number (95%CI: 15.1%-31.1%), 19.3% against hospital visit due to ILI (95%CI: 8.2%-29.1%) and 25.8% against self-medication due to ILI (95%CI: 9.3%- 39.3%). Modeling splitting 643 children with 2017-2018 vaccination into those before and after vaccination, the influenza VE was 31.9% against ILI case number (95%CI: 12.7%-46.9%), 32.6% against hospital visit due to ILI (95%CI: 8.6%-50.3%) and 44.3% against self-medication due to ILI (95%CI: 11.9%-64.8%) in children aged 36-72 months. However, the children aged 6-35 months showed no significant VEs. For the VE analysis in children with different vaccination status, the VEs were significant if they received vaccination in both 2016-2017 season and 2017-2018 season or only in 2017-2018 seasons. The VE was not demonstrated among the children who were immunized only in 2016-2017 season. Conclusion: Influenza vaccination is moderate effective in preventing the incidence of ILI and hospital visit and self-medication in children in influenza season, the protection effect in children aged 36-72 months is better than that in children aged 6-35 months.

Effect of vitrification solutions on survival rate of cryopreserved Epinephelus moara embryos.

Embryo cryopreservation is important for long-term preservation of germplasm and assisted reproduction. However, it is still very difficult to obtain viable embryos from cryopreserved fish embryos. In this study, embryos of Epinephelus moara were used to investigate the effects of various cryopreservation methods. Embryos in stages 10 pairs somite (10S), 18 pairs somite (18S), 22 pairs somite (22S), tail-bud (TB), embryo twitching (ET) and pre-hatch (PH) were treated with five-step equilibrium penetration in 40% PMG3T vitrification solution, which contained 15.75% 1,2-propylene glycol, 10.50% Methanol, 8.75% Glycerol and 5.00% Trehalose. We found that 18S, 22S, TB and ET stage embryos had higher survival rates and were more tolerant to the vitrification solution. Five-step equilibrium treatments on the embryos at the tail-bud stage were performed using two vitrification solutions: 40% PMG3T and 40% PMG3S, which consisted of 15.75% 1,2-propylene glycol, 10.50% Methanol, 8.75% Glycerol and 5.00% Sucrose. The embryonic survival rate under PMG3S treatment (63.36%) was significantly higher than PMG3T treatment (43.93%) (P < 0.05). PMG3S and PMG3T with concentrations of 35%, 40% and 45% were tested on tail-bud stage embryos. Higher concentration of the vitrification solution led to significantly lower embryonic survival rate (P < 0.05). The survival rate was 36.79-72.05% in PMG3S, and 37.11-55.18% in PMG3T, and there were non-significant differences in embryonic development and malformation rates among the groups treated with different concentrations. The embryonic normal development rates in PMG3S and PMG3T were 21.27% and 11.04%, and the malformation rates were 36.13% and 31.04%, respectively. The optimum treatment condition was 40 min using 40% PMG3S on embryos at the tail-bud stage. Both PMG3S and PMG3T were used for cryopreserving embryos at 16 pairs somite, tail-bud and ET stage in liquid nitrogen, where we obtained 190 surviving embryos, and 44 fishes underwent normal development and hatched. The survival rate of cryopreserved embryos was 5.15%, the normal development rate was 1.31%, and the malformation rate was 3.66%. We found that PMG3S and PMG3T were effective for cryopreservation of Epinephelus moara embryos. The results provide a foundation for further explorations of fish embryo cryopreservation techniques.

Self-assembly of highly conductive self-n-doped fullerene ammonium halides and their application in the in situ solution-processable fabrication of working electrodes for alcohol electrooxidation.

Stable and highly conductive self-n-doped fullerene ammonium halides are promising optoelectronic materials. It is necessary to thoroughly understand their structure-function relationship and to develop their applications. Here, the assembly behaviors of the self-n-doped fullerene ammonium halides, as well as the functional areas in the well-developed 2D-3D lamellar structures in their ordered aggregates are systematically characterized using comprehensive methods. In the self-assembly, the solvation effect of DMSO promotes the flexibility of side-chains and drives the formation of fullerene ammonium halides into ordered bilayer structures. The conductivity-active area, which contains tightly packed halide anions sandwiched between fullerenes, provides good electron transfer property. Remarkably, residual DMSO in the side-chain area can induce aqueous Pd precursor into the highly conductive framework. After reduction, Pd nanoparticles are immobilized in the confined spaces within the conductive support. The resulting electrode can be used to electrooxidize ethanol. This study provides a facile solution strategy for the in situ fabrication of electrocatalysts on working electrodes, which can be applied in direct alcohol fuel cells.