ABSTRACT. The effect of sub-lethal doses of Azadirachta indica (Meliaceae) oil on the midgut of Spodoptera frugiperda (Lepidoptera, Noctuidae). The fall armyworm, Spodoptera frugiperda, is one of the major field pests for maize production. It is mainly controlled by means of synthetic, and more recently by resistant cultivar of maize expressing Bt toxins. The neem tree, Azadirachta indica, is a plant that can potentially control insects with the advantage of being food and environmental safe. The aim of this study was to assess the effect of neem oil on the development and survival of S. frugiperda caterpillars by assessing histological alterations caused on their midgut. Newly hatched caterpillars were submitted to three neem oil concentrations: 0.006; 0.05; 0.4%, which were added to their artificial diet. Ten 3 rd instar caterpillars, taken from each treatment, were submitted to histological analysis. The alimentary canals from the specimens were fixed in Baker for 12 hours, desiccated and diaphanized in alcohol/xylol (1:1) and xylol. After placing the samples in paraffin, they were sliced in 8 µm sections and stained with hematoxylineosin stain. The neem oil added to the diet of S. frugiperda caused total mortality at dose of 0.4% whilst still in the first instars, prolonged the larval and pupal stages, and reduced the pupal weight. Histo-physiological alterations such as degeneration of the epithelial lining of the midgut and in the peritrophic matrix were found at all concentrations of neem oil.KEYWORDS. Fall armyworm; histological analysis; insecticidal plants; neem. RESUMO. Efeito de doses subletais do óleo de Azadirachta indica (Meliaceae) no mesêntero de Spodoptera frugiperda (J. E. Smith) (Lepidoptera, Noctuidae). A lagarta-do-cartucho, Spodoptera frugiperda, é a mais importante praga da cultura do milho. Esta é usualmente, controlada por inseticidas sintéticos e mais atualmente por meio de variedades resistentes de milho com a toxina Bt. O nim Azadirachta indica é planta com potencial no controle de insetos, que possui as vantagens de segurança alimentar e ambiental. Objetivou-se com este estudo avaliar o efeito do óleo do nim no desenvolvimento e sobrevivência de lagartas de S. frugiperda em decorrência das alterações no mesêntero. As lagartas recém nascidas foram submetidas a três concentrações do óleo de nim: 0,006; 0,05; 0,4%, adicionadas à dieta artificial. Dez lagartas do 3º instar, retiradas de cada tratamento, foram submetidas à análise histológica. O canal alimentar dos indivíduos foi fixado em Baker por 12 horas, desidratado, diafanizado em álcool/xilol (1:1) e xilol. Após a inclusão em parafina, as amostras foram seccionadas em 8 µm e coradas pela técnica de hematoxilina-eosina. Observou-se que o óleo de A. indica adicionado à dieta de S. frugiperda causa: mortalidade total na dosagem 0,4% nos primeiros instares, aumento na duração do período larval e pupal, redução no peso de pupas. Alterações histofisiológicas, como degeneração do epitélio do revestimento do mesêntero, da matriz peritrófi...
Alelopatia é a capacidade que determinadas plantas têm de interferir no metabolismo de outras, por meio de substâncias liberadas no ambiente, podendo ser uma alternativa de combate às plantas invasoras, dispensando ou reduzindo a utilização dos herbicidas. Levando-se em consideração este fator, o objetivo deste trabalho foi avaliar o potencial alelopático da parte externa e interna da casca de P. ramiflora na germinação e crescimento inicial de plântulas de alface. Os extratos foram obtidos via turbolise, sendo 40 g da planta para 200 mL de água/álcool. Os bioensaios foram diluídos do extrato bruto (20%) em concentrações de 2,5, 5, 10 e 15% e o delineamento estatístico utilizado foi inteiramente casualizado, com médias comparadas pelo teste de Tukey. Não foi observada alteração na germinação nas concentrações dos extratos testados (etanólico e aquoso das partes externa e interna) das cascas de P. ramiflora, além dos extratos também não terem interferido na velocidade de germinação e tempo médio de germinação. Porém, as diferentes concentrações prejudicaram o desenvolvimento da raiz e da parte aérea, principalmente as concentrações de 2,5 e 5,0% do extrato etanólico da parte interna da casca, efeito associado à presença de esteróides e triterpenos, presentes neste extrato. A casca de P. ramiflora, apesar de não afetar negativamente as taxas de germinação, possui a presença de aleloquímicos que interferiram negativamente no crescimento das plântulas de alface, indicando efeito alelopático e potencial de utilização.
ABSTRACT:The interference of chemicals in the germination and growth of plant species, known as allelopathy, is one of the main ways of eliminating competition for resources through the release of allelochemicals. The aim of this study was to determine the presence of secondary metabolites in extracts prepared from leaves of Vochysia haenkeana, evaluating their allelopathic action on the germination and seedling growth of lettuce and tomato. The plant material was collected in the Taboco region, Mato Grosso do Sul state, and after drying and grinding, underwent extraction with the use of water and ethanol, concentration of 200.0 g L -1 . The method using an ultrasound bath was followed by maceration for 24 h in the refrigerator without the presence of light. The extracts were subjected to classical phytochemical analysis and the determination of pH, electrical conductivity, soluble solids and allelopathic tests. For bioassays, the extracts were diluted at concentrations of 25.0, 50.0, 100.0 and 150.0 g L -1 and the experimental design was completely randomized. There was a reduction in the percentage and speed of germination at concentrations of 25.0 and 50.0 g L -1 in both extracts. The seedling growth was also adversely affected, both in the germination chamber and in the greenhouse. These results are probably associated with the presence of different allelochemicals in the extracts, such as phenolic compounds and flavonoids, indicating that this species presented allelopathic action.
Crotalinae snake venoms cause severe local myonecrosis and microvasculature failure at the bite site. We evaluated whether low-level laser therapy (LLLT) could accelerate angiogenesis and myoregeneration in male Swiss mice injected with Bothrops moojeni venom through immunohistochemistry of the vascular endothelial growth factor receptor-1 (VEGFR-1). Envenomed gastrocnemius was either unirradiated (V) or irradiated with HeNe (VHN, 632.8 nm) or GaAs (VGA, 904 nm, 10000 Hz). Animals sacrificed at 3 and 12 h were irradiated once (4 J cm(-2)), at 24 h (twice) and at 3, 7, 21 days (4, 8, 22 times, respectively). At 3 days, LLLT increased angiogenesis (80%:HeNe vs 40%:GaAs), decreased neutrophils and increased proliferation of regenerating cells. However, after 21 days, myoregeneration observed in the VHN group appeared delayed compared with the V group. As LLLT improved revascularization, the suggestive delay in myoregeneration could be a dose-response inhibitory effect caused by multiple irradiations in myogenesis. The immunodetection of VEGFR-1 in neutrophils, macrophages, satellite cells, fibroblasts, Schwann cells and skeletal and smooth muscle fibers (not seen in saline-controls) at only the acute stages of envenoming suggests a mediator role for VEGFR-1 in local alterations. This is the first time that VEGFR-1 expression, and its modulation by photostimulation, has been demonstrated in endothelial and nonendothelial cells of snake envenomed skeletal muscle.
In the Southern Pantanal, the hyacinth macaw (Anodorhynchus hyacinthinus), an endangered species, often chooses the manduvi tree (Sterculia apetala) as a nesting site, because of its physical properties. In addition, the chemical composition of the wood may also contribute to a nesting selection by the hyacinth macaws. The objective of this study was to determine the main chemical components of S. apetala bark for two seasons, and evaluate its fungicidal potential. Bark samples from S. apetala trees with and without nests of A. hyacinthinus were collected in January (wet season) and August (dry season) of 2012. The inhibition of mycelium growth (MGI) from tree samples with and without nests were assessed using a phytochemical analysis to evaluate their antifungal activity against Trichoderma sp. Phytochemical analysis confirmed the presence of phenolic compounds and flavonoids. In both seasons, samples obtained from nested trees had higher content of total phenols than those collected from non-nested trees. The average content of total flavonoids was higher in January for samples with nest and in August for samples without nest. All selected samples showed antifungal activity, and those with nest collected in August (peak of hyacinth macaw breeding) resulted in an MGI of 51.3%. Therefore, this percentage, related to the content of flavonoids and the presence of coumarins, may influence the reproductive success of hyacinth macaws and other species of birds, in this region. This is the first chemical study report with the stem bark of S. apetala.
Colorectal cancer exerts a strong influence on the epidemiological panorama worldwide, and it is directly correlated to etiologic factors that are substantiated by genetic and environmental elements. This complex mixture of factors also has a relationship involving the structural dependence and composition of the gut microbiome, leading to a dysbacteriosis process that may evolve to serious modifications in the intestinal lining, eventually causing the development of a neoplasm. The gastrointestinal tract presents defense strategies and immunological properties that interfere in intestinal permeability, inhibiting the bacterial translocation, thus maintaining the integrity of intestinal homeostasis. The modulation of the intestinal microbiome and the extinction of risk factors associated with intestinal balance losses, especially of environmental factors, make cell and defense alterations impossible. This modulation may be conducted by means of functional foods in the diet, especially soluble fibers, polyunsaturated fatty acids, antioxidants and prebiotics that signal immunomodulatory effects in the intestinal microbiota, with preventive and therapeutic action for colorectal cancer. In summary, this review focuses on the importance of dietary modulation of the intestinal microbiota as an instrument for dysbacteriosis and, consequently, for the prevention of colorectal cancer, suggesting anticarcinogenic, and antiangiogenic properties. Among the intestinal modulating agents considered here are functional foods, especially flaxseed, oat and soy, composing a Bioactive Food Compound.
RESUMO -O objetivo deste trabalho foi analisar a pele de três espécies de peixes (piavuçu Leporinus macrocephalus, pacu prata Mylossoma sp e piraputanga Brycon hilarii) através de análise histologica e morfometrica e testes de resistência após o curtimento. Amostras de peles da região dorsal foram coletadas, fixadas em Bouin por 24 horas, incluídas em parafina, cortadas em 5 µm de espessura e coradas por Hematoxilina-eosina. Os cortes foram analisados pela microscopia de luz. Foi utilizado o dinamômetro EMIC para a análise físico-mecânica do couro em 10 amostras no sentido longitudinal a partir da região dorsal do peixe de cada espécie. A derme desses peixes possui um padrão estrutural comum aos teleósteos, porém a disposição e distribuição das fibras colágenas apresentaram-se diferentes entre as espécies analisadas. Através da análise morfométrica constatou-se que a espessura da derme da pele diferiu entre as três espécies. Não houve diferença no teste de resistência à tração no couro da piraputanga (16,88 N/mm 2 ) e piavuçu (18,50 N/mm 2 ). Os resultados para os couros destas duas espécies de peixes foram superiores ao pacu (11,83 N/mm 2 ). O valor de alongamento até a ruptura foi superior para piavuçu (52,83%) e piraputanga (60,45%), não diferindo entre eles, porém foi inferior para o pacu (33,83%). O rasgamento progressivo foi maior no couro de pacu (36,51 N/mm). As peles das três espécies analisadas podem ser transformadas em couro para sua aplicação em diversos artefatos.Palavras-chave: derme, resistência, fibras colágenas, histologia, morfometria, testes físico-mecânicos Analysis of the Skin of Three Fish Species: Histology, Morphometry and Resistance TestsABSTRACT -This study was carried out to analyse the skin of three species of fish (piavuçu Leporinus macrocephalus, pacu prata Mylossoma sp e piraputanga Brycon hilarii) through histological and morphometrical analysis and resistance tests after hardening. Skin samples from the dorsal region were taken and fixed in Bouin solution for 24 hours. They were embedded in paraffin, cut 5 µm thick and stained by Hematoxylin-eosin technique. The cuts were analyzed by light microscopy. A EMIC dynamometer was used for the physical mechanical analysis of the skin in 10 samples, longitudinally oriented from the dorsal region of each specie of fish. The dermis of those fishes has a structural pattern common to teleosts, but the setting and distribution of collagen fibers was different among the analyzed species. The skin dermis thickness differed among the three species by the morphometrical analysis. No difference was observed for the resistance test to traction in piraputanga leather (16.88 N/mm 2 ) as well as in piavuçu leather (18.50 N/mm 2 ). The results for the skin of both fish species were higher than those for pacu (11.83 N/mm 2 ). The value of stretching as to the point of rupture was higher for piavuçu (52.83%) and piraputanga (60.45%), showing no difference among them, but it was lower for pacu (33.83%). The progressive tearing was greater in pacu ski...
The use of chemical defensives to control fungal diseases has by consequence to impact negatively over the environment and human health, this way, the use of plant extracts with antifungal properties along with proper cultural management makes viable an alternative plant production control, specially for familiar and organic cultures. The objective of this study was to perform phytochemical and antioxidant analysis of Byrsonima crassifolia (canjiqueira) barks and evaluate its antifungal potential over Fusarium solani and Sclerotinia sclerotiorum mycelial growth. The ethanol extract from plants collected in Pantanal, Mato Grosso do Sul, Brazil was submitted to phytochemical prospection, total phenol and flavonoids quantification and antioxidant activiy determination (DPPH). To evaluate antifungal activity concentrations of 800, 1200, 1600, 2000 and 2400 µg 100 mL -1 of ethanol extract were used. Which concentration was separately incorporated in agar (PDA) and shed in Petri dishes, followed by the fungi mycelial disc where the colonies diameter was measured daily. Negatives control with agar without extract and agar with an ethanol solution were used. The B. crassifolia ethanol extract presented inhibitory activity over the fungi studied where concentrations of 800 and 1600 µg 100 mL -1 , inhibited 38% of the mycelial growth of F. solani; to S. sclerotiorum the best concentration was 2400 µg 100 mL 1 , reducing 37.5%. The antifungal bark extract potential of this specie is attributed to phenolic compounds and to triterpenes derivatives.
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