RESUMEN
In the 21st century, severe droughts associated with climate change will increase biomass burning (BB) in Brazil caused by the human activities. Recent droughts, especially in 2005, 2010, and 2015, caused strong socioeconomic and environmental impacts. The 2015 drought considered the most severe since 1901, surpassed the 2005 and 2010 events in respect to area and duration. Herein, based on satellite data, the 2005, 2010 and 2015 drought impacts on wildfire episodes and carbon monoxide (CO) variability during the dry and the dry-to-wet transition seasons were examined. The BB occurrences in the dry season were fewer during 2015 than during 2005 (-44%) and 2010 (-47%). Contrasting, the BB events in the dry-to-wet transition season, were higher during 2015 than during 2005 (+192%) and 2010 (+332%). The BB outbreaks were concentrated in the southern and southwestern Amazon during 2005, in the Cerrado region during 2010, and mainly in the central and northern Amazon during 2015, an area normally with few fires. The CO concentration showed positive variations (up to +30%) occurred in the southern Amazon and central Brazil during the 2005 and 2010 dry seasons, and north of 20 °S during the 2015-2016 dry-to-wet transition season. The BB outbreaks and the CO emissions showed a considerable spatiotemporal variability among the droughts of 2005, 2010, and 2016, first of them driven by local conditions in the tropical North Atlantic (TNA), characterized by warm than normal sea surface waters and the other two by the El Niño occurrences.
Asunto(s)
Monóxido de Carbono/análisis , Sequías/estadística & datos numéricos , Monitoreo del Ambiente , Incendios/estadística & datos numéricos , Biomasa , Brasil , Cambio Climático , Actividades Humanas , Estaciones del AñoRESUMEN
The latex obtained from Hancornia speciosa Gomes (Mangabeira tree) is widely used in traditional medicine to treat a variety of diseases, including diarrhea, ulcer, gastritis, tuberculosis, acne and warts. In this study, the cytotoxicity and genotoxicity effects of H. speciosa latex on the root meristem cells of Allium cepa were examined. Onion bulbs were exposed to different concentrations of latex and then submitted to microscopic analysis using Giemsa stain. Water was used as a negative control and sodium azide as a positive control. The results showed that, under the testing conditions, the mitotic index (MI) of the onion roots submitted to latex treatment did not differ significantly from the negative control, which suggests that the latex is not cytotoxic. Low incidence of chromosome aberrations in the cells treated with H. speciosa latex was also observed, indicating that the latex does not have genotoxic effect either. The MI and the chromosome aberration frequency responded to the latex concentration, requiring more studies to evaluate the dosage effect on genotoxicity. The results indicate that in tested concentrations H. speciosa latex is probably not harmful to human health and may be potentially used in medicine.
Asunto(s)
Apocynaceae/química , Daño del ADN , Látex/toxicidad , Cebollas/efectos de los fármacos , Aberraciones Cromosómicas/efectos de los fármacos , Meristema/efectos de los fármacos , Índice Mitótico , Pruebas de Mutagenicidad , Cebollas/genética , Raíces de Plantas/efectos de los fármacosRESUMEN
Abstract The latex obtained from Hancornia speciosa Gomes (Mangabeira tree) is widely used in traditional medicine to treat a variety of diseases, including diarrhea, ulcer, gastritis, tuberculosis, acne and warts. In this study, the cytotoxicity and genotoxicity effects of H. speciosa latex on the root meristem cells of Allium cepa were examined. Onion bulbs were exposed to different concentrations of latex and then submitted to microscopic analysis using Giemsa stain. Water was used as a negative control and sodium azide as a positive control. The results showed that, under the testing conditions, the mitotic index (MI) of the onion roots submitted to latex treatment did not differ significantly from the negative control, which suggests that the latex is not cytotoxic. Low incidence of chromosome aberrations in the cells treated with H. speciosa latex was also observed, indicating that the latex does not have genotoxic effect either. The MI and the chromosome aberration frequency responded to the latex concentration, requiring more studies to evaluate the dosage effect on genotoxicity. The results indicate that in tested concentrations H. speciosa latex is probably not harmful to human health and may be potentially used in medicine.
Resumo O látex obtido de Hancornia speciosa é amplamente utilizado na medicina popular para tratar uma variedade de doenças, tais como: diarreia, úlcera, gastrite, tuberculose, acne e verrugas. Nesse estudo, foram avaliados os efeitos citotóxicos e genotóxicos do látex de H. speciosa sobre as células meristemáticas das raízes de Allium cepa. Os bulbos das cebolas foram expostos a diferentes concentrações de látex e depois submetidos à analise microscópica usando o corante Giemsa. A água foi usada como controle negativo e a ázida sódica como controle positivo. Os resultados mostraram que o índice mitótico (IM) das raízes de cebola submetidas ao tratamento com látex, nas condições testadas, não diferiram significativamente do controle negativo, e sugerem que o látex não é citotóxico. Também foi observada uma baixa incidência de aberrações cromossômicas nas células tratadas com látex de H. speciosa, o que sugere que o látex também não possui efeito genotóxico. O IM e a frequência de aberrações cromossômicas foram dependentes da concentração de látex. Outros estudos devem ser realizados para avaliar o efeito da dose na genotoxidade. Os resultados indicam que o látex de mangabeira, nas concentrações testadas, provavelmente não é danoso para saúde humana e pode ter potencial para ser usado na medicina.
Asunto(s)
Apocynaceae/química , Daño del ADN , Látex/toxicidad , Cebollas/efectos de los fármacos , Aberraciones Cromosómicas/efectos de los fármacos , Índice Mitótico , Pruebas de Mutagenicidad , Meristema/efectos de los fármacos , Cebollas/genética , Raíces de Plantas/efectos de los fármacosRESUMEN
A doenca de Parkinson (DP) e uma enfermidade cronica de carater progressivo que acomete um em cada mil individuos e apresenta caracteristicas que afetam a qualidade de vida (QV) dessas pessoas. O objetivo dessa revisao e descrever e discutir fatores encontrados na literatura que influenciam a QV dos portaores de tal patologia. Tem sido destacado que o foco de tratamento de individuos com DP deve ser a manuntencao da QV e, para isso, a avaliacao sistematica do paciente e imprescindivel. Tal avaliacao tem sido realizada por meio de instrumentos de medida genericos, especificos ou por uma combinacao de ambos. A DP apresenta sinais e sintomas que afetam a QV do individuo no aspecto fisico, mental/emocional, social e economico. OS sinais e sintomas mais encontrados na literatura e que apresentam maior relevancia sao: bradicinesia, tremor, rigidez, instabilidade postural, disturbios da marcha, dor, fadiga, depressao, disturbios cognitivos sexuais. Alem disso, a limitacao social e as sobrecarga economica sao fatores que tambem afetam diretamente a QV desses individuos. E importante destacar a relacao entre todos os aspectos citados, embora as dimensoes fisica e mental/emocional parecam ser as mais relevantes, uma vez que podem ser as responsaveis pelo desenvolvimento de outras limitacoes. Sendo assim, qualquer programa de tratamento para individuos portadores da DP deve buscar minimizar as limitacoes. Sendo assim, qualquer programa de tratamento para individuos portadores da DP deve buscar minimizar as limitacoes decorrentes da progressao da doenca e procurar contribuir para a melhora da QV dos portadores de tal enfermidade