Objective To investigate the effect of diurnal temperature difference on hospitalization volume of patients with cardiovascular and cerebrovascular diseases in Urumqi City. Methods The daily hospitalization data for cardiovascular and cerebrovascular diseases in Urumqi City from 2019-2021, and meteorological and pollutant data for the same period were collected. The relationship between diurnal temperature range and hospitalizations for cardiovascular and cerebrovascular diseases was analyzed using a distribution lag non-linear model (DLNM), controlling for the long-term trends, the day-of-week effects and other factors. Results The greater the diurnal temperature range, the longer the lag time, and the higher the risk of hospitalization for cardiovascular and cerebrovascular diseases. The lag effect increased significantly when the maximum diurnal temperature range reached 21.0°C. The risk effect appeared on the day of exposure and lasted until day 20, with a maximum RR of 1.266 (95% CI: 1.129-1.421) at a lag of 13 days. At very high diurnal temperature range, the risk of hospitalization for cardiovascular and cerebrovascular diseases was higher in the cold season than that in the warm season. Results after stratified analysis by sex and age showed that men and people aged ≥65 years were more susceptible to diurnal temperature range. Conclusion Extremely high diurnal temperature range is a potential trigger for hospitalization for cardiovascular and cerebrovascular diseases in Urumqi. Men and people aged ≥65 years are more vulnerable to the impact of diurnal temperature range. In the cold season, more attention should be paid to protecting vulnerable people from the impact of the extremely high diurnal temperature difference.

To develop a new recombinant hepatitis E vaccine, we used Hansenula polymorpha expression system to express recombinant hepatitis E virus-like particles (HEV VLPs), to construct a recombinant engineered strain HP/HEV2.3. The fermentation conditions and purification process were studied next. The first working seed lots were fermented in liquid culture, and the fermentation products were collected, then crushed, clarified, purified by ultrafiltration, silica gel adsorbed and desorbed, concentrated by ultrafiltration, purified by liquid chromatography and sterilized by filtration. The purity reached 99% with a yield of 33%. Electron microscopy analysis revealed that both the purified recombinant HEV VLPs from HP/HEV2.3 and natural hepatitis E virus particles appear identical of being 32 nm. The resulting DNA sequence obtained from VLPs is identical to the published HEV sequence. The SDS-PAGE analysis has revealed that the protein molecular weight of the HEV VLPs is 56 kDa, and the expression product HEV VLPs were accumulated up to 26% of total cellular protein. The expression level is 1.0 g/L. Western blotting, enzyme-linked immunosorbent assay (ELISA) results of the protein and ED₅₀ of the vaccine showed that the HEV VLPs have good antigenicity and immunogenicity. In summary, the recombinant HEV VLPs from Hansenula polymorpha can be used in the manufacture of a new genetically engineered vaccine against hepatitis E.