A simulated microgravity-oriented AIE probe-ECM hydrogel-integrated chip for cell culture and superoxide anion radical detection.

Human space activities have been continuously increasing. Astronauts experiencing spaceflight are faced with health problems caused by special space environments such as microgravity, and the investigation of cell injury is fundamental. The development of a platform capable of cell culture and injury detection is the prerequisite for the investigation. Constructing a platform suitable for special conditions in space life science research is the key issue. The ground-based investigation is an indispensable part of the research. Accordingly, a simulated microgravity (SMG)-oriented integrated chip platform capable of 3D cell culture and in situ visual detection of superoxide anion radical (O2•-) is developed. SMG can cause oxidative stress in human cells, and O2•- is one of the signaling molecules. Thus, a O2•--responsive aggregation-induced emission (AIE) probe is designed, which shows high selectivity and sensitivity to O2•-. Moreover, the probe exhibits abilities of long-term and wash-free staining to cells due to the AIE behavior, which is precious for space cell imaging. Meanwhile, a chip with a high-aspect-ratio chamber for adequate medium storage for the lack of the perfusion system during the SMG experiment and a cell culture chamber which can integrate the extracellular matrix (ECM) hydrogel for the bioinspired 3D cell culture is fabricated. In addition, a porous membrane is introduced between the chambers to prevent the hydrogel from separating during the SMG experiment. The afforded AIE probe-ECM hydrogel-integrated chip can achieve 3D culturing of U87-MG cells and in situ fluorescent detection of endogenous O2•- in the cells after long-term staining under SMG. The chip provides a powerful and potential platform for ground-based investigation in space life science and biomedical research.

Analysis on the epidemiological characteristics of varicella and breakthrough case from 2014 to 2022 in Qingyang City.

We analyze the epidemiological characteristics of varicella and breakthrough cases in Qing Yang City, Gansu Province, and provide a basis for the formulation of varicella prevention and control policies. Varicella and breakthrough cases, public health emergency events in Qing Yang City during 2014-2022 were obtained from the China Disease Prevention and Control information System, and the immunization history of the cases were collected from the Gansu Provincial Immunization Planning Information System, descriptive epidemiological analysis of the obtained information was then performed. A total of 6961 cases of varicella were reported in Qing Yang City from 2014 to 2022, yielding an annual incidence of 36.99 cases per 100 000 population. The incidence increased from 19.74/100,000 in 2014 to 35.97/100,000 in 2022; the incidence peaks were observed from May to July and from November to January of the next year. The reported incidence is higher in males (37.70/100,000) than in females (31.54/100,000), and the main age groups were 4 ~ 6 years old (241.98/100,000), 7 ~ 9 years old (142.39/100,000), 10 ~ 14 years old (101.99/100,000). There were 1975 breakthrough cases, accounting for 28.4% of the total reported cases; the majority of patients were students, children in nursery care and scattered children; a total of 10 outbreaks of varicella were reported in primary schools (40.0%), secondary schools (30.0%), kindergartens (20.0%) and high schools (10.0%). The incidence of varicella showed an increasing trend, children and students are high-risk population. It is suggested that varicella vaccine should be included into the immunization program, and the vaccination rate of two-dose of varicella vaccine should be increased for age-eligible children, and varicella surveillance should be strengthened.