ABSTRACT
The potential roles of solar ultraviolet radiation (UVR) as an environmental risk factor in inducing atopic dermatitis (AD) have not been well quantified. To determine the short-term associations between UVR and AD outpatient visits, we obtained daily outpatient visits of AD in Shanghai Skin Disease Hospital from 2013 to 2018. Data of hourly ground UVR were collected. We applied overdispersed generalized additive model to explore its associations. We found that daily exposure to UVR-A rather than UVR-B was positively associated with AD outpatient visits. The visits increased on the present day (lag 0 days) and decreased appreciably with longer lags and became insignificant at lag 4 days. For 10 w/m2 increase in daytime mean and noontime mean exposure to overall UVR and UVR-A from lag 0 to 6 days, the cumulative relative risk of AD was 1.12/1.13 and 1.08/1.08, respectively. Stronger effects of UVR exposure on AD occurred in patients aged 0-7 and > 45 years and in the cold seasons. This study contributed to the few epidemiological evidences that acute exposure to solar UVR may elevate the risks of AD.
Subject(s)
Air Pollution , Dermatitis, Atopic , Air Pollution/analysis , Child , Child, Preschool , China/epidemiology , Dermatitis, Atopic/epidemiology , Humans , Infant , Infant, Newborn , Outpatients , Ultraviolet RaysABSTRACT
The purpose of this study was to investigate the repellent activities of essential oils from Cryptomeria japonica (sugi) against adults of mosquitoes Aedes aegypti and Aedes albopictus . Comparison of essential oils from four different plant parts of C. japonica revealed that essential oil from its leaf exhibited the best repellent activity against mosquitoes. To understand the relationship between volatile organic compounds and repellent activity, the solid-phase microextraction (SPME) method was employed to analyze volatile organic compounds of leaf essential oil. The SPME fiber was coated with divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS). The major volatile organic compounds in the cage were 3-carene, alpha-terpinene, limonene, gamma-terpinene, and terpinolene at 0 min. Results demonstrated that (-)-terpinen-4-ol was the major volatile organic compound adsorbed by SPME fiber during repellent assays. Furthermore, the repellent activities of six compounds against adults of the mosquitoes were evaluated, and the results revealed that (-)-terpinen-4-ol exhibited the best repellent activity against A. aegypti and A. albopictus.
Subject(s)
Aedes/drug effects , Cryptomeria/chemistry , Insect Repellents/pharmacology , Oils, Volatile/pharmacology , Plant Oils/pharmacology , Animals , Insect Repellents/analysis , Oils, Volatile/analysis , Plant Extracts/analysis , Plant Extracts/pharmacology , Plant Oils/analysisABSTRACT
The purpose of this study is to determine the larvicidal activities of ethanolic extracts from leaves, wood, and bark of black heartwood-type Cryptomeria japonica against fourth-instar larvae of mosquitoes Aedes aegypti and Aedes albopictus. Among three ethanolic extracts from C. japonica, wood extract exhibited the best larvicidal activity against A. aegypti and A. albopictus with LC(50) values of 63.2 and 93.8 microg/ml, respectively. Four major compounds, including ferruginol, epi-cubebol, cubebol, and isopimarol, were isolated from wood extract, and it was demonstrated that cubebol exhibited the best activity against A. aegypti and A. albopictus with LC(50) values of 60.1 and 50.0 microg/ml, respectively. Our findings showed that the wood extract and cubebol from C. japonica have good potential as a source for natural larvicides.
