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1.
Clin Cosmet Investig Dermatol ; 15: 1779-1786, 2022.
Article de Anglais | MEDLINE | ID: mdl-36068853

RÉSUMÉ

Objective: To determine if exposure to atmospheric ozone disruption and other factors are associated with photodermatoses in the high-altitude pediatric population in Peru. Materials and Methods: A cross-sectional study based on data obtained from studies of dermatological diseases among the population exposed to mine tailings in Peru which included children under the age of 18 in 6 population centers located over 2500 meters above sea level (m.a.s.l). We evaluated the presence of photodermatoses and possible associated factors obtaining the adjusted odds ratio (aOR) and confidence intervals (CI). Results: 594 children below the age of 18 participated in this study, 53.0% girls, the average age was 10.4 ± 4.1 years. 51.3% were exposed to a mini hole in the ozone layer, 60.1% resided at an altitude over 3500 m.a.s.l and 51.9% presented cutaneous manifestations of atopy upon physical examination. The prevalence of photodermatoses was 64.8%, of which the most frequent were actinic prurigo (49.3%), pityriasis alba (18.5%) and actinic cheilitis (4.4%). The multivariate analysis found that residing in a region exposed to the mini hole in the ozone layer (aOR = 4.23; CI 95%: 2.32-7.72) and residing at an altitude over 3500 m.a.s.l (aOR = 2.76; CI 95%: 1.57-4.86) were both independent associated factors to photodermatoses. Conclusion: A high prevalence of photodermatoses exists among the pediatric population living at high-altitude in Peru. Residing in a region exposed to a mini hole in the ozone layer and residing over 3500 m.a.s.l constituted associated factors.

2.
Ecotoxicol Environ Saf ; 118: 190-198, 2015 Aug.
Article de Anglais | MEDLINE | ID: mdl-25957080

RÉSUMÉ

The increased incidence of solar ultraviolet radiation (UV) due to ozone depletion has been affecting both terrestrial and aquatic ecosystems and it may help to explain the enigmatic decline of amphibian populations in specific localities. In this work, influential events concerning the Antarctic ozone hole were identified in a dataset containing 35 years of ozone measurements over southern Brazil. The effects of environmental doses of UVB and UVA radiation were addressed on the morphology and development of Hypsiboas pulchellus tadpole (Anura: Hylidae), as well as on the induction of malformation after the conclusion of metamorphosis. These analyzes were complemented by the detection of micronucleus formation in blood cells. 72 ozone depletion events were identified from 1979 to 2013. Surprisingly, their yearly frequency increased three-fold during the last 17 years. The results clearly show that H. pulchellus tadpole are much more sensitive to UVB than UVA light, which reduces their survival and developmental rates. Additionally, the rates of micronucleus formation by UVB were considerably higher compared to UVA even after the activation of photolyases enzymes by a further photoreactivation treatment. Consequently, a higher occurrence of malformation was observed in UVB-irradiated individuals. These results demonstrate the severe genotoxic impact of UVB radiation on this treefrog species and its importance for further studies aimed to assess the impact of the increased levels of solar UVB radiation on declining species of the Hylidae family.


Sujet(s)
Anura/croissance et développement , Appauvrissement en ozone , Rayons ultraviolets/effets indésirables , Animaux , Anura/malformations , Anura/génétique , Brésil , Altération de l'ADN
3.
Oecologia ; 116(4): 528-535, 1998 Oct.
Article de Anglais | MEDLINE | ID: mdl-28307522

RÉSUMÉ

We examined the effects of solar ultraviolet-B radiation (UVB) on plant-herbivore interactions in native ecosystems of the Tierra del Fuego National Park (southern Argentina), an area of the globe that is frequently under the Antarctic "ozone hole" in early spring. We found that filtering out solar UVB from the sunlight received by naturally-occurring plants of Gunnera magellanica, a creeping perennial herb, significantly increased the number of leaf lesions caused by chewing insects. Field surveys suggested that early-season herbivory was principally due to the activity of moth larvae (Lepidoptera: Noctuidae). Manipulative field experiments showed that exposure to solar UVB changes the attractiveness of G. magellanica leaf tissue to natural grazers. In a laboratory experiment, locally caught moth caterpillars tended to eat more tissue from leaves grown without UVB than from leaves exposed to natural UVB during development; however, the difference between treatments was not significant. Leaves grown under solar UVB had slightly higher N levels than leaves not exposed to UVB; no differences between UVB treatments in specific leaf mass, relative water content, and total methanol-soluble phenolics were detected. Our results show that insect herbivory in a natural ecosystem is influenced by solar UVB, and that this influence could not be predicted from crude measurements of leaf physical and chemical characteristics and a common laboratory bioassay.

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