987 resultados para Sponge Amphimedon Viridis
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INTRODUCTION: Ayahuasca is a psychotropic plant beverage initially used by shamans throughout the Amazon region during traditional religious cult. In recent years, ayahuasca has also been used in ceremonies of a number of modern syncretic religious groups, including pregnant women. However, no documented study has been performed to evaluate the risk of developmental toxicity of ayahuasca. METHODS: In the present work, maternal and developmental toxicity was evaluated in Wistar rats. Ayahuasca was administered to pregnant rats in three different doses [the equivalent typical dose (TD) administered to humans, five-fold TD and 10-fold TD] during the gestational period (6-20 days). RESULTS: Dams treated with the highest ayahuasca dose showed maternal toxicity with decrease of weight gain and food intake. Visceral fetal findings were observed in all treatment groups. Skeletal findings were observed in the intermediate- and high-dose groups. The fetuses deriving from the highest dose group also presented a decrease in body weight. CONCLUSIONS: From these results, it is possible to conclude that there is a risk of maternal and developmental toxicity following ayahuasca exposure and that the level of toxicity appears to be dose-dependent. Birth Defects Res (Part B) 89:207-212, 2010. (C) 2010 Wiley-Liss, Inc.
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The objective of this study was to evaluate bone formation after application of different doses of recombinant human bone morphogenetic protein-2 (rhBMP-2) combined with monoolein or poloxamer gels, in critical bone defects of rats. Forty-five Wistar rats were divided into nine treatment groups with five animals each: I: application of 1 A mu g rhBMP-2 + monoolein; II: 3 A mu g rhBMP-2 + monoolein; III: 7 A mu g rhBMP-2 + monoolein; IV: 1 A mu g rhBMP-2 + poloxamer; V: 3 A mu g rhBMP-2 + poloxamer; VI: 7 A mu g rhBMP-2 + poloxamer; VII: monoolein only; VIII: poloxamer only; and IX: critical bone defect only. A critical-sized defect of 6 mm diameter was produced in the left parietal bone and it was filled with gels of the above mentioned treatments. After 2 weeks, the calvarial bones were removed for histological processing. Bone formation in the groups that received poloxamer gel and rhBMP-2 was not significantly different from the control group (IX). Groups receiving monoolein and rhBMP-2 (1 and 3 A mu g) and those that received only the carriers (VII and VIII) had less bone formation in relation to the control. The association of rhBMP-2 to both poloxamer and monoolein did not exhibit any significant differentiation in bone formation in comparison with the control group.
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The novel fatty acids 17-methyl-6(Z)-octadecenoic acid and 17-methyl-7(Z)-octadecenoic acid were identified for the first time in nature in the mollusk Siphonaria denticulata from Queensland, Australia. The principal fatty acids in the limpet were hexadecanoic acid, octadecanoic acid, and (Z)-9-octadecenoic acid, while the most interesting series of monounsaturated fatty acids was a family of five nonadecenoic acids with double bonds at either Delta (7), Delta (9), Delta (11), Delta (12), or Delta (13). The novel compounds were characterized using a combination of GC-MS and chemical transformations, such as dimethyl disulfide derivatization. The first total syntheses for the two novel methyl-branched nonadecenoic acids are also described, and these were accomplished in four to five steps and in high yields.
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Habitat use, diet and body-size variation are examined in weevils from Heard Island. with specific attention being given to the Ectemnorhinus viridis species complex. E. viridis shows marked altitudinal variation in body size and vestiture, but there are no consistent associations between body size and diet. nor are there consistent among-individual differences in conventional taxonomic characters. Thus, the status of E. viridis as a single, variable species is maintained. This species occurs from sea level to 600 rn and it feeds on vascular plants and bryophytes. Canonopsis sericeus also feeds on bryophytes and vascular plants and occurs over a narrower altitudinal range. Palirhoeus eatoni is restricted to the surpralittoral zone where it feeds on marine algae and lichens. Bothrometopus brei,is and B. gracilipes both feed on cryptogams, with the former species occurring from sea level to 450 m. and the latter from 50 to 550 m above sea level. In all species, males are smaller than females and there is a size cline such that populations from higher elevations are smaller than those at lower altitudes. This cline is the reverse of that found on the Prince Edward Islands which, unlike Heard Island, lie to the north of the Antarctic Polar Frontal Zone. This difference in body-size clines between weevils on the two island groups is ascribed to the shorter growing season on the colder Heard Island. The information presented here supports previous ideas regarding the evolution of the Ectemnorhinus-group of weevils on the South Indian Ocean Province Islands, although it suggests that subsequent tests of these hypotheses would profit from the inclusion of molecular systematic work.
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In the marine environment a wide range of invertebrates have a pelagobenthic lifecycle that includes planktonic larval and benthic adult phases. Transition between these morphologically and ecologically distinct phases typically occurs when the developmentally competent larva comes into contact with a species-specific environmental cue. This cue acts as a morphogenetic signal that induces the completion of the postlarval/juvenile/adult developmental program at metamorphosis. The development of competence often occurs hours to days after the larva is morphologically mature. In the non-feeding - lecithotrophic - larvae of the ascidian Herdmania curvata and the gastropod mollusc Haliotis asinina, gene expression patterns in pre-competent and competent stages are markedly different, reflecting the different developmental states of these larval stages. For example, the expression of Hemps, an EGF-like signalling peptide required for the induction of Herdmania metamorphosis, increases in competent larvae. Induction of settlement and metamorphosis results in further changes in developmental gene expression, which apparently is necessary for the complete transformation of the larval body plan into the adult form.
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Early development and metamorphosis of Reniera sp., a haplosclerid demosponge, have been examined to determine how gastrulation occurs in this species, and whether there is an inversion of the primary germ layers at metamorphosis. Embryogenesis occurs by unequal cleavage of blastomeres to form a solid blastula consisting micro- and macromeres; multipolar migration of the micromeres to the surface of the embryo results in a bi-layered embryo and is interpreted as gastrulation. Polarity of the embryo is determined by the movement of pigment-containing micromeres to one pole of the embryo; this pole later becomes the posterior pole of the swimming larva. The bi-layered larva has a fully differentiated monociliated outer cell layer, and a solid interior of various cell types surrounded by dense collagen. The pigmented cells at the posterior pole give rise to long cilia that are capable of responding to environmental stimuli. Larvae settle on their anterior pole. Fluorescent labeling of the monociliated outer cell layer with a cell-lineage marker (CMFDA) demonstrates that the monociliated cells resorb their cilia, migrate inwards, and transdifferentiate into the choanocytes of the juvenile sponge, and into other amoeboid cells. The development of the flagellated choanocytes and other cells in the juvenile from the monociliated outer layer of this sponge's larva is interpreted as the dedifferentiation of fully differentiated larval cells-a process seen during the metamorphosis of other ciliated invertebrate larvae-not as inversion of the primary germ layers. These results suggest that the sequences of development in this haplosclerid demosponge are not very different than those observed in many cnidarians.
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Extracts of the dorid nudibranch Asteronotus cespitosus from two geographically separate regions of Australia and from the Philippines were compared using thin-layer, high-performance liquid and gas chromatography and H-1 NMR analysis. Halogenated metabolites were detected in all mollusk specimens. The major component detected in digestive tissue of specimens from the Great Barrier Reef in northeastern Australia was 4,6-dibromo2-(2',4'-dibromophenoxy)phenol (1), with minor amounts of 3,5-dibromo-2(3',5'-dibromo-20-methoxyphenoxy)phenol (2). In a specimen collected from northwestern Australia, only 3,5-dibromo-2-(3',5'-dibromo-2'-methoxyphenoxy)phenol was found. The specimen from the Philippines contained 2,3,4,5-tetrabromo-6-(2'-bromophenoxy) phenol (3) together with a novel chlorinated pyrrolidone (4). In addition, the sesquiterpenes dehydroherbadysidolide (5) and spirodysin (6) were detected in the digestive organs and mantle tissue of the nudibranchs from the Great Barrier Reef and from the Philippines, whereas these chemicals were not found in the specimen from northwestern Australia. All of the chemicals (1-3,5, and 6) have previously been isolated from the sponge Dysidea herbacea, as have chlorinated metabolites related to 4. This is the first time the characteristic halogenated metabolites that typify Dysidea herbacea have been reported from a carnivorous mollusk, which implies a dietary origin as opposed to de novo synthesis.
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Due to the few studies about grafting in net melon, in order to obtain better control of soil pathogens, the aim of the present study was to evaluate 16 genotypes of Cucurbitaceae: Benincasa hispida, Luffa cylindrica, pumpkin 'Jacarezinho', pumpkin 'Menina Brasileira', squash 'Exposição', squash 'Coroa', pumpkin 'Canhão Seca', pumpkin 'Squash', pumpkin 'Enrrugado Verde', pumpkin 'Mini Paulista', pumpkin 'Goianinha', watermelon 'Charleston Gray', melon 'Rendondo Gaucho', melon 'Redondo Amarelo', cucumber 'Caipira HS' and cucumber 'Caipira Rubi', regarding to compatibility of grafting in net melon and resistance to Meloidogyne incognita, based on the reproduction factor (RF), according to Oostenbrink (1966). To assess resistance, the seedlings were transplanted to ceramic pots and inoculated with 300/mL eggs and/or second stage juveniles of M. incognita. At 50 days after transplanting, the plants were removed from the pots and the resistance was evaluated. The compatibility between resistant rootstock and grafts of net melon was determined by performing simple cleft grafting, in a commercial net melon hybrid of great market acceptance and susceptible to M. incognita (Bonus no. 2). The genotypes Luffa cylindrica, pumpkin 'Goianinha', pumpkin 'Mini-Paulista', melon 'Redondo Amarelo', watermelon 'Charleston Gray' are resistant to the nematode M. incognita. The better compatibilities occurred with the rootstocks melon 'Amarelo', which presented 100% of success, followed by pumpkin 'Mini-Paulista' with 94%. On the other hand, Sponge gourd, watermelon 'Charleston Gray' and pumpkin 'Goianinha' showed low graft take percentages of 66%, 62% and 50%, respectively.
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A eficiência energética e a preocupação com a sustentabilidade têm vindo a ganhar preponderância na sociedade moderna. Este trabalho é uma contribuição para esta tendência onde se pretendeu avaliar e sugerir alterações ao sistema de climatização do edifício Biorama do Parque Biológico de Vila Nova de Gaia (PBG). Procedeu-se em primeiro lugar a uma caracterização física, química e geográfica dos 5 biomas constituintes do Biorama. Para isso, recorreu-se a documentos fornecidos pelo próprio PBG, visitas ao local e registo de medições de alguns parâmetros (temperatura, humidade relativa, qualidade do ar). Posteriormente foi realizado o balanço térmico dos edifícios, de acordo com a legislação em vigor, recorrendo a expressões e conceitos teóricos. Foram determinados valores dos ganhos térmicos de aquecimento de 15811, 10694, 7939, 9233, e 6621 kWh/ano para Floresta tropical, Mesozoico, Dunas, Savana e Deserto, respetivamente. Foram igualmente determinados valores dos ganhos térmicos no verão de 7093, 4798, 3560, 4144 e 2971 kWh na Floresta tropical, no Mesozoico, nas Dunas, na Savana e no Deserto, respetivamente. As cargas térmicas de aquecimento foram 149, 125, 47, 60 e 51 kW na Floresta tropical, no Mesozoico, nas Dunas, na Savana e no Deserto, respetivamente. As cargas térmicas de arrefecimento foram iguais a 59, 57, 47, 35 e 36 kW na Floresta tropical, no Mesozoico, nas Dunas, na Savana e no Deserto, respetivamente. Algumas soluções são avançadas, bem como alternativas comportamentais de modo a corrigir alguns problemas identificados. Uma proposta é a da instalação de painéis solares e acumuladores de calor, com os quais se estima um ganho médio conjunto de 500 W em cada bioma, e representam um investimento de 1050 euros e terão um retorno de 1 ano. Em relação à humidade é sugerido a utilização mais eficaz dos aspersores existentes e a utilização de esponjas, para fazer subir a humidade relativa para valores superiores a 80%. Em sentido inverso, no inverno, propõem-se a utilização de material higroscópico para fazer baixar a humidade relativa em cerca de 5%. Os custos com os suportes e o material higroscópico rondam os 250 €. Por fim, é sugerido a instalação de um aparelho de ar condicionado de 16 000 BTU no corredor de ligação, pois é a única forma de garantir condições de conforto térmico. Esta proposta de arrefecimento com ar condicionado e ainda o recurso a uma cortina de lâminas de plástico, que servem para efetuar uma separação mais eficiente entre ar frio e ar quente, têm um custo aproximado de 350 €. É ainda sugerida a utilização de lonas ou de uma planta trepadeira com um custo por planta de 5€, nas coberturas dos telhados virados a sul, sendo que a zona do corredor deverá ser totalmente coberta, a fim de evitar a exposição solar direta.
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Dissertação para obtenção do Grau de Mestre em Bioquímica
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In the context of this dissertation several studies were developed resulting in submission and publication “Evaluation of mechanical soft-abrasive blasting and chemical cleaning methods on alkyd-paint graffiti made on calcareous stones” to Journal of Cultural Heritage. (http://dx.doi.org/10.101 /j.culher.2014.10.004)
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Burn wound healing involves a complex set of overlapping processes in an environment conducive to ischemia, inflammation, and infection costing $7.5 billion/year in the US alone, in addition to the morbidity and mortality that occur when the burns are extensive. We previously showed that insulin, when topically applied to skin excision wounds, accelerates re-epithelialization, and stimulates angiogenesis. More recently, we developed an alginate sponge dressing (ASD) containing insulin encapsulated in PLGA microparticles that provides a sustained release of bioactive insulin for >20days in a moist and protective environment. We hypothesized that insulin-containing ASD accelerates burn healing and stimulates a more regenerative, less scarring, healing. Using a heat-induced burn injury in rats, we show that burns treated with dressings containing 0.04mg insulin/cm2, every three days for 9 days, have faster closure, faster rate of disintegration of dead tissue, and decreased oxidative stress.In addition, in insulin-treated wounds the pattern of neutrophil inflammatory response suggests faster clearing of the burn dead tissue. We also observe faster resolution of the pro-inflammatory macrophages. We also found that insulin stimulates collagen deposition and maturation with the fibers organized more like a basket weave (normal skin) than aligned and crosslinked (scar tissue). In summary , application of ASD-containing insulin-loaded PLGA particles on burns every three days stimulates faster and more regenerative healing. These results suggest insulin as a potential therapeutic agent in burn healing and, because of its long history of safe use in humans, insulin could become one of the treatments of choice when repair and regeneration are critical for proper tissue function.
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Polymeric scaffolds used in regenerative therapies are implanted in the damaged tissue and subjected to repeated loading cycles. In the case of articular cartilage engineering, an implanted scaffold is typically subjected to long term dynamic compression. The evolution of the mechanical properties of the scaffold during bioresorption has been deeply studied in the past, but the possibility of failure due to mechanical fatigue has not been properly addressed. Nevertheless, the macroporous scaffold is susceptible to failure after repeated loading-unloading cycles. In this work fatigue studies of polycaprolactone scaffolds were carried by subjecting the scaffold to repeated compression cycles in conditions simulating the scaffold implanted in the articular cartilage. The behaviour of the polycaprolactone sponge with the pores filled with a poly(vinyl alcohol) gel simulating the new formed tissue within the pores was compared with that of the material immersed in water. Results were analyzed with Morrow’s criteria for failure and accurate fittings are obtained just up to 200 loading cycles. It is also shown that the presence of poly(vinyl alcohol) increases the elastic modulus of the scaffolds, the effect being more pronounced with increasing the number of freeze/thawing cycles.
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Publicado em "Journal of tissue engineering and regenerative medicine". Vol. 8, suppl. s1 (2014)
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Root-knot nematodes were found attacking Coffea spp. and also roots of a few weed species usually found in the coffee orchards in São Paulo. C. arabica cv. Catuaí, C. arabica cv. Mundo Novo, Timor Hybrid and a few plants of C. racemosa showed to be susceptible to Meloidogyne exigua. Roots of Ageratum conyzoides, Amaranthus viridis, Bidens pilosa, Coffea arabica cv. Mundo Novo, Coffea racemosa, Commelina virginica, Digitaria sanguinalis, Galinsoga parviflora, Gnaphalium spathulatum, Porophyllum ruderale, Portulaca oleracea, Pterocaulon virgatum and Solanum americanum were disfigured by M. incognita M. arenaria was found attacking roots of Eleusine indica and Gnaphalium spathulatum, and the presence of an unidentified Meloidogyne species was verified in roots of the following species: Vernonia ferruginea, C. arabica x C. canephora, Eupatorium pauciflorum, Coffea canephora cv. Kouillou, Coffea eugenioides, Coffea racemosa, Coffea stenophylla, Euphorbia pilullifera, Solanum americanum, Ageratum conyzoides, Phyllanthus corcovadensis, and Emilia sagittata.