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1.
Plant Biol (Stuttg) ; 26(1): 28-33, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37862291

RESUMO

Floral scent is a key olfactory cue in both diurnal and nocturnal pollination systems. In the case of nocturnal systems, such as bat-pollinated flowers, odour seems to play a more important role than visual cues. Cactaceae include many bat-pollinated species; however, few studies have investigated the olfactory cues in this family. We analysed and compared the chemical composition of the floral bouquet of three chiropterophilous cactus species, among which are a pair of congeners that differ considerably in scent intensity. Our research presents novel findings regarding the floral scent chemistry of chiropterophilous cactus species. We documented the first case of a bat-pollinated cactus whose flowers lack perceptible floral scent and in which no volatile compounds were detected in our chemical analyses. Additionally, we provide a comprehensive analysis of the chemical composition of the floral bouquet of the other two bat-pollinated species, revealing a resemblance among closely related species within the same genus. We highlight the need for further studies using biotests to investigate the mechanisms through which bats find flowers lacking scent.


Assuntos
Cactaceae , Quirópteros , Perfumes , Polinização , Animais , Flores/química , Odorantes/análise , Perfumes/análise , Feromônios
2.
Braz J Biol ; 83: e275069, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37792748

RESUMO

The black aphid Aphis craccivora Koch is one of the main pests of the caupi-bean crop Vigna unguiculata (L.) Walp. Due to the need to find effective and safe methods of control, there has been an increase in research seeking natural alternatives. Thus, the objective of this work was to evaluate the potential of essential oils from jatoba Hymenaea courbaril, copaiba Copaifera langsdorffii and aroeira Schinus terebinthifolius to control nymphs and adults of A. craccivora. The oils were extracted from the leaves by the hydrodistillation method, diluted to 0.1% in distilled water with 2% dimethyl sulfoxide (DMSO). Each treatment had four repetitions, plus a control with distilled water + 2% DMSO. The biotests were conducted in two stages: the first was conducted in the laboratory, under controlled conditions of temperature, relative humidity and photophase, and the second was conducted in the greenhouse, using only the treatment with the best laboratory test results. After 24, 48, 72, 96 and 120 hours of exposure, the insect mortalities were checked. In the first phase of the experiment, the aroeira oil showed 83.33% and 75.75% efficiency of mortality in nymphs and adults, respectively. In the greenhouse tests, this same oil showed 73.52% in nymphs and 62.85% in adults, opening new perspectives regarding its use as a natural insecticide for the control of the black aphid of the bean.


Assuntos
Afídeos , Fabaceae , Óleos Voláteis , Animais , Óleos Voláteis/farmacologia , Dimetil Sulfóxido , Ninfa , Água
3.
Braz. j. biol ; 83: e275069, 2023. tab, graf
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1513850

RESUMO

Abstract The black aphid Aphis craccivora Koch is one of the main pests of the caupi-bean crop Vigna unguiculata (L.) Walp. Due to the need to find effective and safe methods of control, there has been an increase in research seeking natural alternatives. Thus, the objective of this work was to evaluate the potential of essential oils from jatoba Hymenaea courbaril, copaiba Copaifera langsdorffii and aroeira Schinus terebinthifolius to control nymphs and adults of A. craccivora. The oils were extracted from the leaves by the hydrodistillation method, diluted to 0.1% in distilled water with 2% dimethyl sulfoxide (DMSO). Each treatment had four repetitions, plus a control with distilled water + 2% DMSO. The biotests were conducted in two stages: the first was conducted in the laboratory, under controlled conditions of temperature, relative humidity and photophase, and the second was conducted in the greenhouse, using only the treatment with the best laboratory test results. After 24, 48, 72, 96 and 120 hours of exposure, the insect mortalities were checked. In the first phase of the experiment, the aroeira oil showed 83.33% and 75.75% efficiency of mortality in nymphs and adults, respectively. In the greenhouse tests, this same oil showed 73.52% in nymphs and 62.85% in adults, opening new perspectives regarding its use as a natural insecticide for the control of the black aphid of the bean.


Resumo O pulgão preto Aphis craccivora Koch é uma das principais pragas da cultura do feijão-caupi Vigna unguiculata (L.) Walp. Em virtude da necessidade de encontrar métodos eficazes e seguros de controle, tem-se aumentado as pesquisas buscando alternativas naturais. Dessa forma, o objetivo deste trabalho foi avaliar o potencial dos óleos essenciais de jatobá Hymenaea courbaril, copaíba Copaifera langsdorffii e aroeira Schinus terebinthifolius para controlar ninfas e adultos de A. craccivora. Os óleos foram extraídos das folhas pelo método de hidrodestilação, diluídos a 0,1% em água destilada com Dimetilsufóxido a 2% (DMSO). Cada tratamento possuiu quatro repetições, além da testemunha com água destilada + DMSO 2%. Os biotestes foram conduzidos em duas etapas: a primeira foi realizada em laboratório, sob condições controladas de temperatura, umidade relativa do ar e fotofase e a segunda foi realizada em casa de vegetação, utilizando apenas o tratamento com melhor resultado do teste em laboratório. Depois de transcorridos 24, 48, 72, 96 e 120 horas de exposição, foram verificadas as mortalidades dos insetos. Na primeira fase do experimento, o óleo de aroeira apresentou 83,33% e 75,75% de eficiência de mortalidade em ninfas e adultos, respectivamente. Nos testes em casa de vegetação, esse mesmo óleo apresentou 73,52% em ninfas e 62,85% e em adultos, abrindo novas perspectivas quanto à sua utilização como inseticida natural para o controle do pulgão preto do feijoeiro.

4.
Plant Biol (Stuttg) ; 23(5): 719-727, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34171178

RESUMO

The Neotropical orchid genus Sarcoglottis comprises ~40 species, which emit strong floral scents, presumably involved in pollinator attraction. Information on basic aspects of its natural history is scant, with the few studies available so far pointing to nectar-seeking orchid bees as pollinators. Here, we investigated the reproductive biology of Sarcoglottis acaulis, addressing the ecological meaning of its floral scent. In Atlantic Forest fragments of NE Brazil, we described the floral biology, determined the breeding system and recorded the pollinators of S. acaulis. Additionally, we chemically characterized its floral scent and assessed its role on pollinator attraction. Although self-compatible, S. acaulis depends on pollinators to boost fruit set. Male orchid bees of Eulaema atleticana and E. niveofasciata were the only recorded pollinators. They foraged for nectar only, in spite of the strong scent emitted by S. acaulis flowers. The floral scent is composed of six compounds, of which geraniol and nerol elicited electroantennographic responses in Eulaema bees. A synthetic mixture of these compounds attracted Eulaema bees in field assays but did not trigger the stereotyped scent-gathering behaviour. The floral scent of S. acaulis acts in signalling and nectar is the sole reward for pollinators. Despite the low pollinator frequency, S. acaulis shows a high fruit set (77%), particularly when compared to other orchids. Attributes such as pollinia that release small pollen loads, allowing a single pollinia-carrying bee to pollinate several flowers, low amount of nectar, steady-state flowering and traplining behaviour of pollinators, might act together to assure this outstanding fruit set.


Assuntos
Orchidaceae , Perfumes , Animais , Abelhas , Flores , Melhoramento Vegetal , Néctar de Plantas , Polinização
5.
Plant Biol (Stuttg) ; 23(1): 100-110, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32757308

RESUMO

Several monoecious species of palms have developed complex strategies to promote cross-pollination, including the production of large quantities of floral resources and the emission of scents that are attractive to pollinators. Syagrus coronata constitutes an interesting model with which to understand the evolution of plant reproductive strategies in a monoecious species adapted to seasonally dry forests. We monitored blooming phenology over 1 year, during which we also collected and identified floral visitors and putative pollinators. We identified potential floral visitor attractants by characterizing the scent composition of inflorescences as well as of peduncular bracts, during both male and female phases, and the potential for floral thermogenesis. Syagrus coronata produces floral resources throughout the year. Its inflorescences are predominantly visited by a diverse assortment of small-sized beetles, whose richness and abundance vary throughout the different phases of anthesis. We did not find evidence of floral thermogenesis. A total of 23 volatile compounds were identified in the scent emitted by the inflorescences, which did not differ between male and female phases; whereas the scent of the peduncular bracts was composed of only 4-methyl guaiacol, which was absent in inflorescences. The composition of floral scent chemistry indicates that this palm has evolved strategies to be predominantly pollinated by small-sized weevils. Our study provides rare evidence of a non-floral scent emitting structure involved in pollinator attraction, only the second such case specifically in palms. The peculiarities of the reproductive strategy of S. coronata might play an important role in the maintenance of pollination services and pollen dispersion.


Assuntos
Arecaceae/fisiologia , Flores/fisiologia , Odorantes , Animais , Insetos , Polinização
6.
Rev. chil. enferm. respir ; 36(4)dic. 2020.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1388125

RESUMO

Resumen La Fibrosis Quística (FQ) es la enfermedad hereditaria de pronóstico reservado más frecuente en raza blanca. Desde el año 2003, Chile inicia un Programa Nacional de Fibrosis Quística, de carácter integral, dirigido por la Unidad de Salud Respiratoria del Ministerio de Salud. Hasta la fecha, los principales resultados del Programa registran una significativa mayor sobrevida (promedio 27 años) y una significativa reducción en la edad de diagnóstico de los pacientes ingresados desde 2006 en adelante. El acceso a la canasta GES (Garantías Explícitas en Salud), la implementación del tamizaje neonatal en algunas regiones del país, la organización y la constitución de equipos entrenados en FQ de diversas especialidades, ha contribuido a mejorar los resultados. Si bien las principales manifestaciones son del aparato respiratorio y digestivo, el carácter multisistémico de la FQ obliga a conocer los distintos aspectos involucrados en su manejo, a fin de optimizar los resultados del tratamiento y los recursos invertidos, tanto en el sector público como privado. Este documento es una revisión y actualización sobre los principales aspectos del diagnóstico, seguimiento y tratamiento de las manifestaciones respiratorias y no respiratorias de la FQ.


Cystic Fibrosis (CF) is the most frequent hereditary disease in whites, with a reserved prognosis. Since 2003, Chile began a comprehensive National Cystic Fibrosis Program, directed by the Respiratory Health Unit of the Ministry of Health. To date, the main results of the Program record a significantly longer survival (average 27 years) and a significant reduction in the age of diagnosis of patients admitted from 2006 onwards. Access to Chilean Explicit Health Guarantees, the implementation of neonatal screening in some regions of the country, the organization and setting up of CF-trained teams of various specialties, has contributed to improving results. Although the main manifestations are of the respiratory and digestive system, the multisystemic nature of CF makes it necessary to know the different aspects involved in its management, in order to optimize the results of the treatment and the resources invested, both in the public and private sectors. This document is a review and an update on the main aspects of the diagnosis, monitoring and treatment of the respiratory and non-respiratory manifestations of CF.

7.
Neumol. pediátr. (En línea) ; 15(4): 429-483, 2020. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-1146394

RESUMO

Cystic Fibrosis (CF) is the most frequent hereditary disease in whites, with a reserved prognosis. Since 2003, Chile began a comprehensive National Cystic Fibrosis Program, directed by the Respiratory Health Unit of the Ministry of Health. To date, the main results of the Program record a significantly longer survival (average 27 years) and a significant reduction in the age of diagnosis of patients admitted from 2006 onwards. Access to Chilean Explicit Health Guarantees, the implementation of neonatal screening in some regions of the country, the organization and setting up of CF-trained teams of various specialties, has contributed to improving results. Although the main manifestations are of the respiratory and digestive system, the multisystemic nature of CF makes it necessary to know the different aspects involved in its management, in order to optimize the results of the treatment and the resources invested, both in the public and private sectors. This document is a review and an update on the main aspects of the diagnosis, monitoring and treatment of the respiratory and non-respiratory manifestations of CF.


La Fibrosis Quística (FQ) es la enfermedad hereditaria de pronóstico reservado más frecuente en raza blanca. Desde el año 2003, Chile inicia un Programa Nacional de Fibrosis Quística, de carácter integral, dirigido por la Unidad de Salud Respiratoria del Ministerio de Salud. Hasta la fecha, los principales resultados del Programa registran una significativa mayor sobrevida (promedio 27 años) y una significativa reducción en la edad de diagnóstico de los pacientes ingresados desde 2006 en adelante. El acceso a la canasta GES (Garantías Explícitas en Salud), la implementación del tamizaje neonatal en algunas regiones del país, la organización y la constitución de equipos entrenados en FQ de diversas especialidades, ha contribuido a mejorar los resultados. Si bien las principales manifestaciones son del aparato respiratorio y digestivo, el carácter multisistémico de la FQ obliga a conocer los distintos aspectos involucrados en su manejo, a fin de optimizar los resultados del tratamiento y los recursos invertidos, tanto en el sector público como privado. Este documento es una revisión y actualización sobre los principales aspectos del diagnóstico, seguimiento y tratamiento de las manifestaciones respiratorias y no respiratorias de la FQ.


Assuntos
Humanos , Criança , Adulto , Prestação Integrada de Cuidados de Saúde , Fibrose Cística/diagnóstico , Fibrose Cística/terapia , Chile , Estado Nutricional , Fibrose Cística/reabilitação , Consenso , Recursos em Saúde
8.
Biotech Histochem ; 94(7): 498-513, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31064227

RESUMO

Essential oils are a promising alternative to insecticides. We investigated the LD50 of oils extracted from Piper corcovadensis, P. marginatum, and P. arboreum after 48 h topical contact with Spodoptera frugiperda larvae using morphometry, histochemistry and immunohistochemistry of the midgut and fat body. Chromatography revealed that E-caryophyllene was the principal compound common to the Piper species. The essential oils of P. corcovadensis, P. marginatum and P. arboreum caused deleterious changes in the midgut of S. frugiperda larvae. P. corcovadensis oil produced the lowest LD50 and significant histopathological alterations including elongation of the columnar cells, formation of cytoplasmic protrusions, reduction in carbohydrate, increased apoptotic index and decreased cell proliferation. P. arboreum oil caused histopathological alterations similar to P. corcovadensis, but caused the highest rate of cell proliferation and increased regenerative cells, which indicated rapid regeneration of the epithelium. Our findings demonstrated the insecticidal potential of P. corcovadensis for control of S. frugiperda owing to the significant damage it inflicted on S. frugiperda midgut.


Assuntos
Corpo Adiposo/efeitos dos fármacos , Corpo Adiposo/patologia , Óleos Voláteis/farmacologia , Piper/metabolismo , Animais , Sistema Digestório/metabolismo , Sistema Digestório/patologia , Corpo Adiposo/metabolismo , Inseticidas/metabolismo , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Óleos Voláteis/química , Piper/química , Óleos de Plantas/metabolismo , Óleos de Plantas/farmacologia , Spodoptera
9.
Rev Gastroenterol Mex (Engl Ed) ; 84(4): 427-433, 2019.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-30292584

RESUMO

INTRODUCTION AND OBJECTIVE: Eosinophilic esophagitis is a chronic, immune-mediated disease described in case series and publications worldwide. Over the past twenty years, the authors of different studies have attempted to evaluate its incidence and prevalence. The objetive of the present study was to estimate the prevalence of eosinophilic esophagitis in a group of children seen at 36 pediatric gastroenterology centers in ten Latin American countries. MATERIALS AND METHODS: A multicenter, observational, and cross-sectional study was conducted that estimated the period prevalence of eosinophilic esophagitis in children seen at outpatient consultation and that underwent diagnostic upper gastrointestinal endoscopy for any indication at 36 centers in 10 Latin American countries, within a 3-month time frame. RESULTS: Between April and June 2016, 108 cases of eosinophilic esophagitis were evaluated. Likewise, an average of 29,253 outpatient consultations and 4,152 diagnostic upper gastrointestinal endoscopies were carried out at the 36 participating centers. The period prevalence of eosinophilic esophagitis in the population studied (n=29,253) was 3.69 cases×1,000 (95% CI: 3.04 to 4.44), and among the children that underwent routine upper gastrointestinal endoscopy (n=4,152), it was 26x1,000 (95% CI: 22.6 to 29.4). CONCLUSIONS: The general period prevalence of eosinophilic esophagitis in a group of children evaluated at 36 Latin American pediatric gastroenterology centers was 3.69×1,000, and in the children that underwent endoscopy, it was 26×1,000. There was important prevalence variability between the participating countries and centers. The present analysis is the first study conducted on the prevalence of pediatric eosinophilic esophagitis in Latin America.


Assuntos
Esofagite Eosinofílica/epidemiologia , Adolescente , Criança , Pré-Escolar , Estudos Transversais , Feminino , Gastroenterologia , Hospitais Especializados , Humanos , Lactente , América Latina/epidemiologia , Masculino , Prevalência
10.
Rev. Odontol. Araçatuba (Impr.) ; 39(2): 37-46, maio/ago. 2018. graf, tab
Artigo em Português | LILACS, BBO - Odontologia | ID: biblio-913512

RESUMO

A glutamina é o aminoácido livre mais abundante no organismo humano, responsável por desempenhar diversas funções fisiológicas. Em situação de hipercatabolismo como estresse, trauma, infecções e condições de exercícios físicos extremos, sua produção pelos tecidos se torna insuficiente para suprir suas necessidades, classificando este aminoácido como condicionalmente essencial. Durante o exercício exaustivo, a glutamina é utilizada para síntese de trifosfato de adenosisa (ATP) reduzindo sua disponibilidade para o sistema de defesa antioxidante e imune. Dessa forma, a suplementação da glutamina vem sendo estudada como uma possibilidade de recuperar o sistema imune e melhorar o desempenho de atletas em períodos de exercícios exaustivos. O presente estudo teve como objetivo verificar o efeito da suplementação da glutamina no sistema imunológico sobre os diferentes tipos de exercício físico. Foi realizada uma pesquisa bibliográfica a partir de artigos publicados junto ao banco de dados do Google acadêmico, Scielo e Bireme. A suplementação da glutamina, aliada ao exercício físico, parece melhorar o sistema imune, porém há necessidade de mais estudos para comprovar sua efetividade no auxílio ergogênico para melhorar o desempenho físico(AU)


Glutamine is the most abundant free amino acid in the human body, responsible for performing many physiological functions. In a situation of hypercatabolism such as stress, trauma, infections and extreme physical exercises conditions, its production from the tissues becomes insufficient to supply its needs, classifying this amino acid as conditionally essential. During exhaustive exercise, glutamine is used for adenosine triphosphate (ATP) synthesis reducing its availability to the immune and antioxidant defense system. In this way, glutamine supplementation has been studied as a possibility to recover the immune system and to improve the performance of athletes in periods of exhaustive exercises. The current study aims to verify the effect of glutamine supplementation on the immune system on the different types of physical exercise. A bibliographic search was done from articles published with the database of academic Google, Scielo and Bireme. Glutamine supplementation, combined with physical exercise, seems to improve the immune system, but there is a need for further studies to prove its effectiveness in ergogenic assistance to improve physical performance(AU)


Assuntos
Exercício Físico , Glutamina , Sistema Imunitário , Imunidade , Resistência Física
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