948 resultados para Algas verdes


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As doenças inflamatórias intestinais são enfermidades onde a tolerância e homeostase da resposta inflamatória estão comprometidas, gerando lesões teciduais e favorecendo o surgimento de neoplasias. Há dois importantes exemplos de doenças inflamatórias intestinais, a colite ulcerativa, foco do modelo desse estudo, e a doença de Crohn. Os medicamentos utilizados no tratamento dessas doenças desencadeiam diversos efeitos adversos; além disso, em alguns pacientes, eles não são eficazes. Os extratos de algas têm demonstrado várias atividades biológicas, entre elas a atividade anti-inflamatória. Os extratos das algas do gênero Caulerpa foram utilizados em vários estudos, onde modelos inflamatórios foram analisados, entre eles o modelo de colite ulcerativa. A utilização do extrato metanólico da C. mexicana como terapêutica nesse modelo atenuou o quadro clinico desenvolvido pelos animais. Sendo assim, o presente estudo teve como objetivo analisar a ação terapêutica da Caulerpina (CLP), extraída da C. racemosa, no modelo murino de colite ulcerativa. Camundongos C57BL/6 machos foram expostos a uma solução de Dextrana Sulfato de Sódio (DSS) a 3% por sete dias. A partir do primeiro dia de exposição ao DSS os animais foram tratados em dias alternados com a CLP nas doses de 4 e 40 mg/kg e com a dexametasona (3 mg/kg) por via oral. O desenvolvimento da doença foi analisado através do índice de atividade da doença (IAD), que leva em consideração a perda de peso corporal, a consistência e a presença de sangue nas fezes. Após a eutanásia, o cólon foi removido e mensurado, e amostras do tecido colônico foram destinadas a análise histológica e à cultura para dosagem de citocinas. Os níveis de citocinas no sobrenadante da cultura do cólon foram mensurados por ELISA. O tratamento com a CLP (4 mg/kg) desencadeou significativa melhora quanto à perda de peso corporal e ao IAD, e atenuou o encurtamento do cólon em resposta ao DSS. Tal dose foi capaz de reduzir os níveis de citocinas pró-inflamatórias analisadas (TNF-, IFN-, IL-6, IL-17), mas não teve efeito significativo nas citocinas anti-inflamatórias IL-10 e TGF-. O tratamento com a CLP (40 mg/kg) não foi eficaz quanto a perda de peso e ao IAD, além de não ter atenuado a redução do cólon em resposta ao DSS. Essa dose conseguiu reduzir os níveis das citocinas pró-inflamatórias, porém não os níveis de IL-6. O tratamento com a dexametasona obteve melhora discreta quanto à perda de peso corporal e ao IAD, porém não atenuou a redução do cólon em resposta ao DSS. Esse tratamento também conseguiu reduzir todas as citocinas pró-inflamatórias testadas. Deste modo a CLP (4 mg/kg) demonstrou ser uma alternativa promissora no tratamento da colite ulcerativa, em razão dos seus efeitos benéficos sobre parâmetros clínicos, morfológicos e moleculares do modelo em estudo

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This work aimed to study the diversity and distribution of marine sea turtles stranded in Potiguar Basin, Rio Grande do Norte, as well as aspects related to feeding behavior associated with human impacts. The study was conducted through the analysis of data from stranded animals, recorded in a daily monitoring in an area bounded on the north by the municipality of Aquiraz, in the state of Ceará, and the east by the municipality of Caicara do Norte, in the state of Rio Grande do Norte. Stranded dead animals were necropsied and for the analysis of the diet of animals, esophagus, stomach and intestines were fixed in 10% formalin and after that, the stomach contents were sorted and stored in 70% alcohol. Representative fragments of these organs were removed for making histological slides, with a view to histological characterization of the digestive tract. 2.046 occurrences of turtles were recorded during the period from 01/01/2010 to 31/12/2012. The Chelonia mydas species showed the highest number of records and it was observed in 66.81 % (N = 1,367) of cases; followed by Eretmochelys imbricata with 4.45 % (N = 91) and by Lepidochelys olivacea with 1.22% (N = 25). The Caretta caretta and Dermochelys coriacea species were, respectively, 0.93 % (N = 19) and 0.05 % (N = 1) records of strandings. In 26.54 % of cases, it was not possible to identify the species. Regarding the spatial distribution, the stretch A was the one that had the highest number of strandings and a larger number of records were registered in the warm months of the year. The dietary analysis showed that C. mydas fed preferentially on algae; C. caretta had a diet with a predominance of the item "coral´s fragments" and E. imbricata species showed preference for an animal origin material. Related to this anthropic interaction, 57.14 % (n = 76) of animals that died at the rehabilitation s base, showed cause of death due to complications from ingesting debris. According to the data presented, the Potiguar Basin presents itself as an area with important diversity and distribution of marine sea turtle as well is characterized as a feeding and nidification area for these species

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Este trabalho teve por objetivo determinar a ocorrência e a freqüência de fungos em banana 'Prata anã' e elucidar o agente causal das podridões em pós-colheita de frutos provenientes do norte de Minas Gerais. Dois métodos de isolamento foram adotados: diluição em placas, a partir da lavagem de frutos verdes, e direto de frutos maduros. Os fungos Colletotrichum musae, Trichoderma harzianum, Fusarium equisetii, Penicillium sp. Aspergillus parasiticus, Trichothecium roseum, Colletotrichum acutatum, Alternaria sp., Cladosporium musae e Curvularia lunata foram os mais freqüentemente associados aos frutos. A patogenicidade desses fungos foi testada pela substituição de discos da casca de frutos verdes por discos de micélio. Colletotrichum musae apresentou área média lesionada em torno do ponto de inoculação igual a 5,8 cm², enquanto para os demais fungos testados não passou de 1,50 cm². Os resultados mostraram que C. musae é o agente primário das podridões dos frutos examinados com 100 % de incidência e os demais fungos limitaram-se a necrosar os ferimentos em torno do ponto de inoculação. O modo de infecção latente, causada por C. musae, parece favorecer, primeiramente, a colonização interna dos tecidos e, posteriormente, a ação dos fungos oportunistas, que aceleram as podridões nos frutos e na coroa.

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Sulfated polysaccharides (SP) are widely distributed in animals and seaweeds tissues. These polymers have been studied in light of their important pharmacological activities, such as anticoagulant, antioxidant, antitumoral, anti-inflammatory, and antiviral properties. On other hand, SP potential to synthesize biomaterials like as nanoparticules has not yet been explored. In addition, to date, SP have only been found in six plants and all inhabit saline environments. However, the SP pharmacological plant activities have not been carrying out. Furthermore, there are no reports of SP in freshwater plants. Thus, do SP from marine plants show pharmacological activity? Do freshwater plants actually synthesize SP? Is it possible to synthesize nanoparticles using SP from seaweed? In order to understand this question, this Thesis was divided into tree chapters. In the first chapter a sulfated polysaccharide (SPSG) was successfully isolated from marine plant Halodule wrightii. The data presented here showed that the SPSG is a 11 kDa sulfated heterogalactan contains glucose and xylose. Several assays suggested that the SPSG possessed remarkable antioxidant properties in different in vitro assays and an outstanding anticoagulant activity 2.5-fold higher than that of heparin Clexane® in the aPTT test; in the next chapter using different tools such as chemical and histological analyses, energy-dispersive X-ray analysis (EDXA), gel electrophoresis and infra-red spectroscopy we confirm the presence of sulfated polysaccharides in freshwater plants for the first time. Moreover, we also demonstrate that SP extracted from E. crassipes root has potential as an anticoagulant compound; and in last chapter a fucan, a sulfated polysaccharide, extracted from the brown seaweed was chemically modified by grafting hexadecylamine to the polymer hydrophilic backbone. The resulting modified material (SNFuc) formed nanosized particles. The degree of substitution for hydrophobic chains of 1H NMR was approximately 93%. SNFfuc-TBa125 in aqueous media had a mean diameter of 123 nm and zeta potential of -38.3 ± 0.74 mV, measured bydynamic light scattering. Tumor-cell (HepG2, 786, H-S5) proliferation was inhibited by 2.0 43.7% at SNFuc concentrations of 0.05 0.5 mg/ mL and RAEC non-tumor cell line proliferation displayed inhibition of 8.0 22.0%. On the other hand, nanogel improved CHO and RAW non-tumor cell line proliferation in the same concentration range. Flow cytometric analysis revealed that this fucan nanogel inhibited 786 cell proliferation through caspase and caspaseindependent mechanisms. In addition, SNFuc blocks 786 cell passages in the S and G2-M phases of the cell cycle

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

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Fucana é um termo que define uma família de hetero e homopolissacarídeos que contem L-fucose em sua estrutura. Neste trabalho uma hererofucan F 2,0v da alga Dictyota menstrualis foi avaliada como agente antinociceptivo e antiinflamatório. A fucana F 2,0v inibiu a migração de leucócitos em até 100% (20.0 mg/kg) para a cavidade peritoneal após estimulo químico, porém, não alterou a expressão das interleucinas IL-1β, IL-6 e de TNF-α. Com relação a sensação dolorosa a F 2,0v (20.0 mg/kg) possui atividade antinociceptiva periférica com potência semelhante à dipirona. Por outro lado não apresentou efeito no teste da placa quente. Análises de microscopia confocal e citometria de fluxo mostram que a F 2,0v se liga a superfície dos leucócitos. O conjunto de resultados apresentados pela fucana F 2,0v sugerem que o mecanismo de ação está relacionado com sua capacidade de inibir a migração de leucócitos para o local da injúria tecidual. Em resumo os dados mostram que F 2,0v apresenta grande potencial como composto antinociceptivo e antiinflamatório. Estudos futuros serão realizados para caracterizar melhor o mecanismo de ação da F 2,0v

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Plântulas de Cybistax antisyphilitica (ipê-verde), espécie arbórea que ocorre no Estado de São Paulo, Brasil, foram estudadas morfoanatomicamente e citogeneticamente. As plântulas são eudicotiledôneas, fanerocotiledonares e epigéias. Suas sementes apresentam alas hialinas, assimétricas e de textura papirácea. A raiz é axial com tecido epidérmico irregular. O hipocótilo é verde, glabro e apresenta os elementos do xilema em diferenciação. Os cotilédones são verdes, foliáceos, reniformes, com mesofilo heterogêneo, epiderme pilosa e feixes vasculares colaterais. Os eófilos são glabros, peciolados, de filotaxia oposta, dorsiventrais, hipoestomáticos e possuem mesofilo heterogêneo e assimétrico. Não há diferenças anatômicas significativas entre os eófilos e os metáfilos. O sistema vascular do pecíolo dos metáfilos dispõe-se em forma de ferradura. A espécie apresenta número cromossômico mitótico 2n = 40 com comprimento cromossômico geral médio de 1,042 µm ± 0,140 e amplitude variando de 0,58 µm até 1,60 µm.

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The regulation of the inflammatory response is essential to maintain homeostasis. Several studies have been performed to search new drugs that can contribute to avoiding or minimizing an excessive inflammatory process. The aim of this study was to evaluate the effect of extracts of green algae Caulerpa mexican in models of inflammation. In mice, the model of peritonitis induced inflammatory zymosan pretreatment of mice with aqueous and methanol extracts of C. mexican was able to reduce cell migration to the peritoneal cavity. Treatment of mice with extracts of C. mexican also reduced the ear edema induced by xylene and exerted inhibitory action on the migration of leukocytes in inflammation-induced zymosan the air pouch, and timedependent for the extracts tested in the model of ulcerative colitis induced by DSS 3%, the extract methanol, but not the aqueous C. mexican, significantly reduced the clinical symptoms of colitis, as well as the production of proinflammatory cytokines in the culture of mouse colon, in the histological analysis there was a slight reduction of inflammation in the intestinal mucosa. We concluded that the administration of the extracts resulted in the reduction of cell migration to different sites as well as reducing the edema formation induced by chemical irritant. This study demonstrates for the first time the antiinflammatory effect of aqueous and methanolic extracts from green marine algae Caulerpa mexican

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The main aim of this study was to compare the procedure for dehydration of Gracilaria birdiae prepared handmade and laboratory, collected in the northern coast of Rio Grande do Norte. The sample was collected in the Rio do Fogo beach in march 2009. The sample collected followed by two processing, the first the material prepared in laboratory was air-dried at 50°C for 24 hours in air-flow oven. The second the handmade sample was air-dried on the sun during three days. The extract was prepared in three different solvents: ethanol, hydroethanol and water, resulting in ethanol, hidroethanol and aqueous extracts from handmade and laboratory sample. In according with results only the ethanol extract was fractionated yielding the fractions hexane, dichloromethane and ethyl acetate fractions. The different process to obtain Gracilaria birdiae resulted in the samples with different shades. The soluble solids content was higher in the laboratory sample. The chemical composition the both samples were characterized by presenting a considerable amounts of carbohydrates, with amior percentage protein and ash, respectively, in the handmade and laboratory sample. In two samples showed a low content of lipids and the lipid profile showed a higher proportion of monounsaturated fatty acids, with the absence polyunsaturated handmade sample. The phytochemical screening by chemical reactions showed the presence of flavonoids, tannins, alkaloids and saponins the laboratory sample, presenting a greater diversity of bioactive compounds. Through of the analysis by thin layer chromatography was possible to identify the phytosterols β-sitosterol and stigmasterol the both samples, also suggest the presence of β-carotene and chlorophyll α the laboratory sample. The levels of total phenolics and flavonoids were more significant in the ethanol extract of the laboratory sample. The in vitro lethality showed that extracts of the laboratory sample and handmade from 125 to 500 μg/ mL, respectively, were highly lethal. In the evaluation of antioxidant capacity by the system β-carotene/ácido linoleic method and by DPPH radical scavernging assay, the ethanol extract from the laboratory process showed significantly greater activity than the other extracts, being and the first and second methods, respectively, lower and equivalent to the synthetic antioxidant BHT. The handmade ethanol extract has not demonstrated skill in deactivating free radicals, but showed activity in inhibiting lipid peroxidation, although the values were significantly lower than the laboratory sample. We conclude that the dehydration process in the laboratory is the most efficient technique to maintenance of the chemical composition present in the seaweed, providing beneficial properties such as antioxidant capacity. We emphasize that this property can be explored with the objective of adding commercial value to the final product, which will promote the expansion of production of this seaweed in the community of Rio do Fogo

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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O objetivo do presente estudo foi avaliar os efeitos de diferentes dosagens de cloreto de mepiquat, thidiazuron e ethephon, aplicadas parceladamente no algodoeiro (Gossypium hirsutum L.) na Fazenda Itamarati, Ponta Porã, MS. As dosagens de cloreto de mepiquat foram: (0; 12,5 + 12,5 + 25,0 = 50; 25 + 25 + 25 = 75; 0 + 50 + 50 = 100; 12,5 + 62,5 + 50 = 125) g ha-1, com aplicações efetuadas aos 34, 47 e 62 dias após a emergência (DAE) em 1993/94, e aos 42, 60 e 73 DAE, em 1994/95, enquanto o thidiazuron foi aplicado quando 70% dos capulhos estavam abertos, nas dosagens de 0, 45, 60 e 75 g ha-1; já o ethephon foi aplicado sete dias após o thidiazuron, quando já se observava desfolha de 85%, nas dosagens de 0, 960 e 1.440 g ha-1. O delineamento experimental utilizado foi o de blocos casualizados em faixa, com subparcelas subdivididas e quatro repetições. O cloreto de mepiquat proporcionou redução do número de frutos verdes, aumento do peso de 100 sementes e do peso médio de um capulho; a percentagem de desfolha aumentou com as dosagens de thidiazuron e ethephon; constatou-se que a interação cloreto de mepiquat x thidiazuron x ethephon foi significativa para percentagem de abertura de capulhos e produção de algodão em caroço.

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The reef area of Pirangi beach has been experiencing antropogenic actions, mainly due to tourism activity. In order to evaluate these effects, surveys on seaweeds were conducted at nine stations located over the fringing reef. Benthic community (seaweeds/corals) were identified using the photoquadrat method, with 50 meters random transects located paralleled to the coast. The general categories evaluated in each transect were: rock, sand, seaweeds, corals and mollusks. Data achieved were processed at Coral Point Count with Excel Extensions software. A total of 30 seaweed species, 5 coral species and 1 mollusk species were identified. There was a high dominance of short algae at stations with high tourism pressure, whereas frondose algae usually occurred at places without human interference. Seaweeds with the highest percent cover were composed by Sargassum vulgare (59%), Caulerpa racemosa (47%) and Dictyopteris delicatula (33%). Cluster analyses considering benthic organisms revealed five benthic features: (1) submersed area characterized by a diversified marine flora; (2) area with dominance of Caulerpa racemosa and presence of Millepora alcicornis; (3) area with high cover of Sargassum vulgare; (4) trampling area characterized by bare rocks, short algae and Zoanthus sociatus and (5) area with high coverage of Palythoa caribaeroum. Obtained data suggest that the studied area has been damaged by tourism activities. Furthermore, observed differences in algal communities may be a good indicator of ecosystem health of Pirangi reefs

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Octopus insularis, target species in this study, is the dominant benthic octopus of the North and Northeast Brazil. Studies on behavior and ecology of the species have been conducted primarily on oceanic islands, with little information on the continental populations. In this study, two regions of the coast of RN, Rio do Fogo and Pirangi, were chosen for the characterization of the niche by O. insularis populations. The dietary niche, habitat and distribution of O. insularis of oceanic islands and the mainland, were compared. In addition, individual characteristics of feeding behavior in a population at Atol das Rocas was studied, taking into account the size of individuals, the proximity of the dens and characteristics of their "personality". The diet of the Rio do Fogo population was composed mainly of bivalve molluscs (82%), unlike Pirangi population that has a diet consisting mainly of crustaceans Decapoda (68%), similar to that described for the populations of the islands. Consequently, the feeding niches of the island populations were more similar, with greater overlap, but the niche breadth of the continent was larger. The habitats of occurrence on the coast includes reefs, rocks, gravel and an environment called Restinga, a plateau composed of biogenic gravel, sand, sponges and algae, showed a high density of animals. Similarly to that found in the islands, O. insularis in the continent, had a clumped distribution, and a bathymetric segregation between small and large individuals. The differences in diet composition among populations were explained by differences in habitat and coverage of the substrate, which may be directly influencing the diversity and prey availability in these environments. The individual analyzes of the population at Atol das Rocas, showed no relationship between the degree of individual specialization and the different personalities, or the distance between dens. The results suggest that the foraging strategy with greater availability of prey in the environment has an influence on diet octopuses over preferences or personalities

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Branches of coffee-plant were collected in Sao Sebastiao do Paraiso County, Minas Gerais State, at the Experimental Station of the Agricultural Research Company (Empresa de Pesquisa Agropecuaria de Minas Gerais - EPAMIG), with the aim of studying various aspects of oviposition by Quesada gigas (Hemiptera: Cicadidae). The number of branches with Q. gigas egg nests was analyzed, as well as the number of nests per branch, the eggs per nest and the diameter of the egg nest location on the branch. The preference for oviposition either on alive or dry branches and the size of the egg were assessed. Egg-laying occurred only on dry branches. The mean of the branch diameter on which the egg nests occurred was 2.5 +/- 0.53 mm. The number of eggs per nest averaged 13.2 +/- 4.9, and the number of egg nests per branch was 2.2 +/- 1.74. The eggs were 1.9 +/- 0.08 mm long by 0.5 +/- 0.04 mm wide. The largest diameters of the branches containing egg nests were found on the upper third of the trees, as well as the greatest amount of branches with egg nests, of egg nests per branch and of eggs per nest. The correlation relationship between all of the experiment variables was positive.