Study on Morphological Changes and Interference in the Development of Aedes aegypti Caused by Some Essential Oil Constituents.

Dengue, Chikungunya and Zika are arboviruses, transmitted by the mosquito Aedes aegypti, that cause high mortality and serious health consequences in human populations. Efforts to control Ae. aegypti are important for preventing outbreaks of these diseases. Essential oil constituents are known to exhibit many activities, such as their use as larvicides. Given their potential, the present study aimed to characterize the larvicidal effect of dihydrojasmone, p-cymene, carvacrol, thymol, farnesol and nerolidol on the larvae of Ae. aegypti and their interference over the morphology of the mosquitos. The essential oil constituents were dissolved in dimethylsulfoxide at concentrations of 1-100 µg/mL and were applied in the breeding environment of third-stage larvae. The larvae from bioassays were fixed, dehydrated and embedded. Ultrathin sections were contrasted using 5% uranyl acetate and 1% lead citrate for observation through transmission electron microscopy. The oil with the highest larvicidal efficiency was found to be nerolidol, followed by farnesol, p-cymene, carvacrol, thymol and dihydrojasmone, with an LC50 of 11, 21, 23, 40, 45 and 66 µg/mL, respectively. The treated Ae. aegypti larvae caused alteration to the tegument or internal portions of larvae. The present study demonstrated which of these oils-dihydrojasmone, farnesol, thymol, p-cymene, carvacrol and nerolidol-have effective larvicidal activity.

Percepção da equipe de enfermagem frente ao aleitamento materno: do conhecimento à implementação / Perception of the nursing team front to breastfeeding: from knowledge to Implementation

Este estudo objetivou compreender a percepção da equipe de enfermagem acerca da amamentação na primeira hora após o nascimento do bebê, avaliar o entendimento da equipe de enfermagem acerca da importância de proporcionar a amamentação do bebê na primeira hora do pós-parto e identificar as ações da equipe de enfermagem para garantir a amamentação precoce do concepto. Trata-se de um estudo qualitativo de abordagem descritiva. A pesquisa foi realizada no Maternidade Mariana Bulhões, situada no Município de Nova Iguaçu. Os sujeitos da pesquisa foram enfermeiros e técnicos de enfermagem, que atuam diretamente no pós-parto. A coleta dos dados ocorreu no mês de outubro 2018. Os dados foram analisados através de análise de conteúdo. Conclui-se que algumas barreiras são encontradas por profissionais quanto a aceitação das puérperas acerca do aleitamento materno, demonstrando a necessidade de uma sistematização por parte da equipe (multiprofissional) com ações educativas sobre a temática.

This study aimed to understand the nursing team's perception of breastfeeding in the first hour after the baby's birth, Assess the understanding of the nursing team about the importance of providing breastfeeding to the baby in the first hour of postpartum and identify the actions of the nursing team to ensure early breastfeeding of the conceptus. This is a qualitative study with a descriptive approach. The research was carried out at the maternity Mariana Bulhões, located in the municipality of Nova Iguaçu. The research subjects were nurses and nursing technicians, who work directly in the postpartum period. Data collection occurred in the month of October 2018. The data were analyzed through content analysis. It is concluded that some barriers Are Found by professionals regarding the acceptance of puerperal women about breastfeeding, demonstrating the need for a systematization On the part of the team (multiprofessional) with educational actions on the subject.

Este estudio apuntó a entender la percepción de la lactancia materna del equipo de enfermería en la primera hora después del nacimiento del bebé, evaluar la comprensión del equipo de enfermería sobre la importancia de proporcionar lactancia materna al bebé em la primera hora de postparto y ientificar las acciones del equipo de enfermería para asegurar la lactancia materna temprana del conceptus. Este es un estudio cualitativo de aproximación descriptiva. La investigación se llevó a cabo en la maternidad Mariana Bulhões, ubicada en el municipio de Nova Iguaçu. Los sujetos de investigación fueron enfermeras y técnicos de enfermería, que trabajan directamente en el período posparto. La recolección de datos se produjo en el mes de octubre 2018. Los datos se analizaron a través del análisis de contenido. Se concluye que algunas barreras Son Encontrado por profesionales con respecto a la aceptación de las mujeres puerperales sobre la lactancia materna, demostrando la necesidad de una sistematización por parte del equipo (multiprofesional) con acciones educativas sobre el tema.

Larvicidal activity of Ottonia anisum metabolites against Aedes aegypti: A potential natural alternative source for mosquito vector control in Brazil.

BACKGROUND & OBJECTIVES: Aedes aegypti mosquito is the principal vector of the viruses responsible for urban yellow fever, dengue, dengue haemorrhagic fever, as well as Zika and chikungunya in Brazil. The present study was aimed to investigate the insecticidal potential of the extract and fractions of Ottonia anisum, along with special metabolites isolated from it, as natural alternatives against larvae (L3) of Ae. aegypti, vector of potentially deadly tropical infections in Brazil. METHODS: The plant species O. anisum was collected in March 2015, at Xerιm area, in Rio de Janeiro City, Brazil. Crude extracts and the isolated pure compounds were screened for toxicity against Ae. aegypti larvae (L3). Bioassays were performed on 20 larvae (L3) of Ae. aegypti in triplicate. The samples were dissolved in a mixture of acetone and DMSO at final concentrations of 1-200 µg/ml. The toxicity of the solutions was evaluated towards the growth and development of Ae. aegypti larvae till emergence of adults. RESULTS: The crude hexane extract showed 100% larval mortality 24 h after treatment at a concentration of 200 µg/ml. The bioassays using 1-butyl-3,4-methylenedioxybenzene revealed 100% mortality among L3 larvae, 24 h afterthe treatment at a concentration of 30 µg/ml, the LC recorded was 1.6 µg/ml. At concentration of 10 µg/ml, the L3 larval mortality recorded was 92%. INTERPRETATION & CONCLUSION: The metabolite 1-butyl-3,4-methylenedioxybenzene showed potent toxicity against Ae. aegypti larvae. This arylbutanoid agent could be used as a natural alternative adjuvant pesticide, in new compositions that would be environmentally safer.

Toxicity and Larvicidal Activity of Podophyllum-Based Lignans Against Aedes aegypti (Diptera: Culicidae).

Aedes aegypti L. (Diptera: Culicidae) is a mosquito species that has adapted to urban environments and is the main vector of dengue viruses. Because of the increasing incidence of dengue, a more environmentally acceptable insecticide needs to be found. Natural products have been and continue to be an important source of leading compounds that can be modified in order to develop new drugs. The lignan family of natural products includes compounds with a diverse spectrum of biological activity. Podophyllotoxin and its related lignans represent an exciting class of natural products that can be targeted at different types of biological activity and are therefore worth exploring further. This study had the aim of evaluating the larvicidal activity of an ethanolic extract from the rhizomes and roots of Podophyllum hexandrum (PM-3) and its isolated lignans, podophyllotoxone (1) and desoxypodophyllotoxin (2), on the larvae of the mosquito vector Ae. aegypti. The PM-3 extract and the compounds (1) and (2) were dissolved in a mixture of acetone and dimethylsulfoxide at final concentrations of 1, 10, 30, 50, 100, and 200 µg/ml. After dilution, the solutions were applied (µg/ml) to the larvae-rearing medium. Overall, the ethanolic extract from the rhizomes and roots of P. hexandrum and the compounds (1) and (2) showed larvicidal activity against the larvae of Ae. aegypti According to the results from this study, it can be concluded that podophyllotoxone (1) and desoxypodophyllotoxin (2) exhibited significant toxicity toward Ae. aegypti larvae.

Cytotoxicity of piperamides towards Aedes aegypti (Diptera: Culicidae).

The effectiveness of the amides piplartine and piperlonguminine isolated from Piper species for controlling L3 and L4 of Aedes aegypti (L.) was assessed through bioassays at concentrations ranging from 1 to 300 g/l ml. Piplartine reduced the mosquito development period and caused larval mortality only at concentrations > 100 microg/ml, whereas piperlonguminine resulted in an extended period of mosquito development (10 microg/ml) and caused 100% larval mortality (30 microg/ml) within 24 h. The toxicity and cytotoxic effects of piperlonguminine on epithelial cells of the digestive system of Ae. aegypti were viewed using transmission electron microscopy, which indicated vacuolization of cytoplasm, mitochondrial swelling and leaking of nuclear material. Piperlonguminine was the more effective amide, showing toxic activity with LD50 of approximately 12 microg/ml against the larvae of Ae. aegypti.

Burchellin: study of bioactivity against Aedes aegypti.

BACKGROUND: The dengue mosquito Aedes aegypti Linnaeus, 1762 is a widespread insect pest of serious medical importance. Since no effective vaccine is available for treating dengue, the eradication or control of the main mosquito vector is regarded as essential. Since conventional insecticides have limited success, plants may be an alternative source of larvicidal agents, since they contain a rich source of bioactive chemicals. The aim of this study was to evaluate the larvicidal activity of the neolignan burchellin isolated from Ocotea cymbarum (Lauraceae), a plant from the Amazon region, against third instar larvae of A. aegypti. METHODS: Burchellin obtained from O. cymbarum was analyzed. The inhibitory activity against A. aegypti eggs and larvae and histological changes in the digestive system of treated L3 larvae were evaluated. In addition, nitric oxide synthase activity and nitric oxide levels were determined, and cytotoxicity bioassays performed. RESULTS: The data showed that burchellin interfered with the development cycle of the mosquito, where its strongest toxic effect was 100% mortality in larvae (L3) at concentrations ≥ 30 ppm. This compound did not show target cell toxicity in peritoneal macrophages from BALB/c mice, and proved to have molecular stability when dissolved in water. The L3 and L4 larvae treated with the compound showed cellular destruction and disorganization, cell spacing, and vacuolization of epithelial cells in small regions of the midgut. CONCLUSION: The neolignan burchellin proved to be a strong candidate for a natural, safe and stable phytolarvicidal to be used in population control of A. aegypti.