The Indian and East Asian summer monsoons are two components of the whole Asian summer monsoon system. Previous studies have indicated in-phase and out-of-phase variations between Indian and East Asian summer rainfall...The Indian and East Asian summer monsoons are two components of the whole Asian summer monsoon system. Previous studies have indicated in-phase and out-of-phase variations between Indian and East Asian summer rainfall. The present study reviews the current understanding of the connection between Indian and East Asian summer rainfall. The review covers the relationship of northern China, southern Japan, and South Korean summer rainfall with Indian summer rainfall; the atmospheric circulation anomalies connecting Indian and East Asian summer rainfall variations; the long-term change in the connection between Indian and northern China rainfall and the plausible reasons for the change; and the influence of ENSO on the relationship between Indian and East Asian summer rainfall and its change. While much progress has been made about the relationship between Indian and East Asian summer rainfall variations, there are several remaining issues that need investigation. These include the processes involved in the connection between Indian and East Asian summer rainfall, the non-stationarity of the connection and the plausible reasons, the influences of ENSO on the relationship, the performance of climate models in simulating the relationship between Indian and East Asian summer rainfall, and the relationship between Indian and East Asian rainfall intraseasonal fluctuations.展开更多
Objective: To explore the impact of seasonal changes on the T-helper 1(Th1)/T-helper 2(Th2) immune balance of the body in order to elucidate the internal immunological mechanisms underlying seasonal eczema.Methods: Ei...Objective: To explore the impact of seasonal changes on the T-helper 1(Th1)/T-helper 2(Th2) immune balance of the body in order to elucidate the internal immunological mechanisms underlying seasonal eczema.Methods: Eighty 4-week-old male Sprague-Dawley rats were divided into 5 season groups kept in corresponding season simulation environments, and subdivided into the model group and the control group. The Eczema Area and Severity Index(EASI) and scratching frequency were evaluated. The serum levels of immunoglobulin E(IgE), interleukin-2(IL-2), interleukin-12(IL-12), and interferon-gamma(IFN-γ), interleukin-4(IL-4), interleukin-25(IL-25), and interleukin-31(IL-31), and melatonin(MT), as well as the MT receptor(MTR) levels in the spleen, were detected by enzyme-linked immunosorbent assay analysis. The mRNA expression levels of T-bet and GATA3 were detected by quantitative real-time polymerase chain reaction.Results: EASI scores and the scratching frequency of the model group were higher in the long summer than in the other 4 seasons. Meanwhile, the serum levels of IgE and the Th2 cytokines IL-4, IL-25, and IL-31, as well as GATA3 mRNA expression levels, were high during the long summer in both groups. However, the serum levels of the Th1 cytokines IL-2, IL-12, and IFN-γ, as well as MT, MTR, and T-bet mRNA levels, were lower during the long summer. In all 5 seasonal groups(spring, summer, long summer, autumn, and winter), the levels of all immune factors, especially IL-4 and IL-31, were higher in the model group than those in the control group,while the concentrations of MT and MTR were lower.Conclusion: Under long light, hot, and humid conditions in the long summer, the body is more likely to suffer from Th2-dominated immune imbalance. This is the internal mechanism behind the high incidence and severity of eczema during the long summer. MT and MTR play a key role in the seasonal onset of eczema.展开更多
基金supported by the National Key Basic Research Program of China(Grant No.2014CB953902)the National Key Research and Development Program of China(Grant No.2016YFA0600603)the National Natural Science Foundation of China(Grant Nos.41475081,41275081 and 41530425)
文摘The Indian and East Asian summer monsoons are two components of the whole Asian summer monsoon system. Previous studies have indicated in-phase and out-of-phase variations between Indian and East Asian summer rainfall. The present study reviews the current understanding of the connection between Indian and East Asian summer rainfall. The review covers the relationship of northern China, southern Japan, and South Korean summer rainfall with Indian summer rainfall; the atmospheric circulation anomalies connecting Indian and East Asian summer rainfall variations; the long-term change in the connection between Indian and northern China rainfall and the plausible reasons for the change; and the influence of ENSO on the relationship between Indian and East Asian summer rainfall and its change. While much progress has been made about the relationship between Indian and East Asian summer rainfall variations, there are several remaining issues that need investigation. These include the processes involved in the connection between Indian and East Asian summer rainfall, the non-stationarity of the connection and the plausible reasons, the influences of ENSO on the relationship, the performance of climate models in simulating the relationship between Indian and East Asian summer rainfall, and the relationship between Indian and East Asian rainfall intraseasonal fluctuations.
基金funded by the Fundamental Research Funds for the Central Universities(2020-JYB-ZDGG-016).
文摘Objective: To explore the impact of seasonal changes on the T-helper 1(Th1)/T-helper 2(Th2) immune balance of the body in order to elucidate the internal immunological mechanisms underlying seasonal eczema.Methods: Eighty 4-week-old male Sprague-Dawley rats were divided into 5 season groups kept in corresponding season simulation environments, and subdivided into the model group and the control group. The Eczema Area and Severity Index(EASI) and scratching frequency were evaluated. The serum levels of immunoglobulin E(IgE), interleukin-2(IL-2), interleukin-12(IL-12), and interferon-gamma(IFN-γ), interleukin-4(IL-4), interleukin-25(IL-25), and interleukin-31(IL-31), and melatonin(MT), as well as the MT receptor(MTR) levels in the spleen, were detected by enzyme-linked immunosorbent assay analysis. The mRNA expression levels of T-bet and GATA3 were detected by quantitative real-time polymerase chain reaction.Results: EASI scores and the scratching frequency of the model group were higher in the long summer than in the other 4 seasons. Meanwhile, the serum levels of IgE and the Th2 cytokines IL-4, IL-25, and IL-31, as well as GATA3 mRNA expression levels, were high during the long summer in both groups. However, the serum levels of the Th1 cytokines IL-2, IL-12, and IFN-γ, as well as MT, MTR, and T-bet mRNA levels, were lower during the long summer. In all 5 seasonal groups(spring, summer, long summer, autumn, and winter), the levels of all immune factors, especially IL-4 and IL-31, were higher in the model group than those in the control group,while the concentrations of MT and MTR were lower.Conclusion: Under long light, hot, and humid conditions in the long summer, the body is more likely to suffer from Th2-dominated immune imbalance. This is the internal mechanism behind the high incidence and severity of eczema during the long summer. MT and MTR play a key role in the seasonal onset of eczema.