ABSTRACT
Background: Scrub typhus has become widespread across various regions in China in recent decades, causing a considerable burden on residents. While meteorological variables significantly impact the spread of scrub typhus, there is insufficient quantitative evidence illustrating this association in known high-endemic areas. Methods: A distributed lag non-linear model was applied to explore the relationship between meteorological parameters and scrub typhus incidence from 2010 to 2019 in Baoshan City, western Yunnan Province, China. Results: High monthly mean (20°C) and maximum (30°C) temperatures were associated with a peak risk of scrub typhus in the current month. Higher minimum temperatures and higher relative humidity were followed by increasing cumulative risks over the ensuing 3 months. Higher precipitation was followed by increasing cumulative risk over the ensuing 2-month period, peaking at around 30 cm. Conclusion: The non-linear lag associations between meteorological parameters and scrub typhus incidence suggest that higher monthly minimum temperature and relative humidity could be associated with an increased risk of scrub typhus in the subsequent several months, while warm temperature is more likely to impact the occurrence of scrub typhus in the current month.
Subject(s)
Humidity , Meteorological Concepts , Scrub Typhus , Scrub Typhus/epidemiology , Humans , China/epidemiology , Incidence , Temperature , Nonlinear Dynamics , Seasons , Risk FactorsABSTRACT
Abstract Purpose: To investigate the impact of different hypoxia reoxygenation (HR) times on autophagy of rat cardiomyocytes (H9C2). Methods: Rat cardiomyocytes were randomly divided into normal control group (group A), hypoxia group (group B), 2 h HR group (group C), 12 h HR group (group D), and 24 h HR group (group E). LC3 II/LC3 I was determined via western blotting, and cell viabilities of cardiomyocytes were measured using methyl thiazolyl tetrazolium (MTT) assay. Results: Cell viabilities in HR model groups were significantly lower than those of group A (P<0.05). LC3 II/LC3 I levels in groups B to D were significantly higher than those of group A (P<0.05), and group D showed the highest LC3 II/LC3 I levels. Cell viabilities in groups B to D were significantly lower than those of group A (P<0.05), with group D showing the lowest cell viabilities (P<0.05). Conclusions: Hypoxia can induce autophagy in rat cardiomyocytes, which can be further activated by reoxygenation; most notable after 12 h. Hypoxia-induced cell injury can be aggravated by reoxygenation. The lowest cell viability was observed at 12 h after reoxygenation; however, cell viability can be recovered after 24 h.