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Background Low-frequency intrahost single-nucleotide variants of SARS-CoV-2 have been recognized as predictive indicators of selection. However, the impact of vaccination on the intrahost evolution of SARS-CoV-2 remains uncertain at present. Methods We investigated the genetic variation of SARS-CoV-2 in individuals who were unvaccinated, partially vaccinated, or fully vaccinated during Shanghai's Omicron BA.2.2 wave. We substantiated the connection between particular amino acid substitutions and immune-mediated selection through a pseudovirus neutralization assay or by cross-verification with the human leukocyte antigen–associated T-cell epitopes. Results In contrast to those with immunologic naivety or partial vaccination, participants who were fully vaccinated had intrahost variant spectra characterized by reduced diversity. Nevertheless, the distribution of mutations in the fully vaccinated group was enriched in the spike protein. The distribution of intrahost single-nucleotide variants in individuals who were immunocompetent did not demonstrate notable signs of positive selection, in contrast to the observed adaptation in 2 participants who were immunocompromised who had an extended period of viral shedding. Conclusions In SARS-CoV-2 infections, vaccine-induced immunity was associated with decreased diversity of within-host variant spectra, with milder inflammatory pathophysiology. The enrichment of mutations in the spike protein gene indicates selection pressure exerted by vaccination on the evolution of SARS-CoV-2. [ABSTRACT FROM AUTHOR]

PURPOSE: To analyze the status of 5-year-old children's oral caries in Shanghai from 2008 to 2011, and to provide information to evaluate oral health status and improve service level. METHODS: By using equal-sized randomly sampling method, this survey was carried out on the caries status of randomly selected 950 children aged 5 years in Shanghai respectively in 2008 and 2009, and 900 children respectively in 2010 and 2011. The data of prevalence of dental caries, dmft, caries filling constituent ratio and SiC index were collected. Statistical analysis was performed using SPSS 13.0 software package by means of independent-samples t test, one way ANOVA and Chi-square test. RESULTS: From 2008 to 2011, the prevalence of deciduous tooth caries among 5-year-old children was 63.47%, 64.00%, 64.89% and 64.44%, respectively. The mean dmft score was 2.96, 2.99, 3.23 and 3.09, respectively. The caries filling ratio was 10.93%, 12.76%, 16.96% and 20.63%, respectively. The SiC index was 7.10, 7.20, 7.74 and 7.37, respectively. The prevalence of caries and mean dmft showed no significant difference in four years (P>0.05), and the caries filling constituent ratio was remarkably increased (P<0.01). The SiC index was two times higher than dmft. Each year the prevalence of deciduous tooth caries and mean dmft in urban areas were lower than in suburban areas (P<0.01), but the children came from urban areas showed significant higher filling rate than those from suburban areas (P<0.01). Deciduous tooth caries were concentrated in one-third of children. CONCLUSIONS: The prevalence of deciduous tooth caries and dmft of 5-year-old children in Shanghai changed little, and the caries filling constituent ratio has increased year by year. To promote children' s oral health further, we still need to take more active preventive measures for high caries risk group. [ABSTRACT FROM AUTHOR]

The 1990 World Values Survey demonstrated that industrialization promotes a shift from traditional to secular-rational values. Drawing data from a sample survey of 2,350 respondents in Shanghai, this study examines the impact of social change on people's values in China. Specifically, we are interested in (1) are there significant differences in values between different generations in China? (2) Do younger generations tend to have more modern values? (3) What are the main factors that affect the differences? The results show that the younger generations in China have already shifted from traditional values to modern values in a recent social transformation process. In addition, the younger generations tend to be more secular. They are more likely to regard self-development as the most important thing in life rather than making contributions to the country and society. Further, the younger generations are more individualistic than the old generations. They are more likely to live according to their own lifestyles regardless of what others think. Thus, they are less likely to follow the traditional collective ideology. Overall, the study shows significant generational gaps in value orientations in China. [ABSTRACT FROM AUTHOR]