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A Biblioteca Digital da Produção Intelectual e Científica da Unicamp tem por objetivo reunir e disseminar a produção intelectual, acadêmica e cultural da universidade e preservar sua memória institucional, além de contribuir para ampliar a visibilidade da instituição e dos seus pesquisadores em âmbito nacional e internacional.

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‣ Endurance training stimulates growth and survival pathways and the redox balance in rat pancreatic islets

Calegari, Vivian C.; Abrantes, Julia L.; Silveira, Leonardo R.; Paula, Flavia M.; Costa, Jose Maria, Jr.; Rafacho, Alex; Velloso, Licio A.; Carneiro, Everardo M.; Bosqueiro, Jose R.; Boschero, Antonio C.; Zoppi, Claudio C.
Fonte: Amer Physiological Soc; Bethesda Publicador: Amer Physiological Soc; Bethesda
Tipo: Artigo de Revista Científica
Português
Calegari VC, Abrantes JL, Silveira LR, Paula FM, Costa JM Jr, Rafacho A, Velloso LA, Carneiro EM, Bosqueiro JR, Boschero AC, Zoppi CC. Endurance training stimulates growth and survival pathways and the redox balance in rat pancreatic islets. J Appl Physiol 112: 711-718, 2012. First published December 15, 2011; doi:10.1152/japplphysiol.00318.2011.-Endurance training has been shown to increase pancreatic beta-cell function and mass. However, whether exercise modulates beta-cell growth and survival pathways signaling is not completely understood. This study investigated the effects of exercise on growth and apoptotic markers levels in rat pancreatic islets. Male Wistar rats were randomly assigned to 8-wk endurance training or to a sedentary control group. After that, pancreatic islets were isolated; gene expression and the total content and phosphorylation of several proteins related to growth and apoptotic pathways as well as the main antioxidant enzymes were determined by real-time polymerase chain reaction and Western blot analysis, respectively. Reactive oxygen species (ROS) production was measured by fluorescence. Endurance training increased the time to reach fatigue by 50%. Endurance training resulted in increased protein phosphorylation content of AKT (75%)...

‣ The Clock Gene Rev-erb alpha Regulates Pancreatic beta-Cell Function: Modulation by Leptin and High-Fat Diet

Vieira, Elaine; Marroqui, Laura; Batista, Thiago M.; Caballero-Garrido, Ernesto; Carneiro, Everardo M.; Boschero, Antonio C.; Nadal, Angel; Quesada, Ivan
Fonte: Endocrine Soc; Chevy Chase Publicador: Endocrine Soc; Chevy Chase
Tipo: Artigo de Revista Científica
Português
Disturbances of circadian rhythms have been associated with obesity and type 2 diabetes. The nuclear receptor Rev-erb alpha was suggested to link circadian rhythms and metabolism in peripheral tissues. The aim of the present study was to dissect the role of this clock gene in the pancreatic beta-cell function and to analyze whether its expression is modulated by leptin and diet-induced obesity. To address the function of Rev-erb alpha, we used small interfering RNA in mouse islet cells and in MIN-6 cells. Cell proliferation was measured by bromodeoxyuridine incorporation, apoptosis by the terminal deoxynucleotidyl transferase dUTP nick end labeling technique, insulin secretion by RIA, and gene expression by RT-PCR. Pancreatic islets were isolated at different zeitgeber times 0, 6, and 12 after 6 wk of high-fat diet treatment, and then gene expression and insulin secretion were determined. Rev-erb alpha down-regulation by small interfering RNA treatment in islet cells and MIN-6 cells impaired glucose-induced insulin secretion, decreased the expression of key lipogenic genes, and inhibited beta-cell proliferation. In vivo and in vitro leptin treatment increased Rev-erb alpha expression in isolated islets through a MAPK pathway. High-fat diet treatment disrupted the circadian Rev-erb alpha gene expression profile along with insulin secretion...

‣ Quantitative coronary arterial stenosis assessment by multidetector CT and invasive coronary angiography for identifying patients with myocardial perfusion abnormalities

Godoy, G. K.; Vavere, A.; Miller, J. M.; Chahal, H.; Niinuma, H.; Lemos, P.; Hoe, J.; Paul, N.; Clouse, M. E.; Ramos, C. D.; Lima, J. A.; Arbab-Zadeh, A.
Fonte: Springer; New York Publicador: Springer; New York
Tipo: Artigo de Revista Científica
Português
Semi-quantitative stenosis assessment by coronary CT angiography only modestly predicts stress-induced myocardial perfusion abnormalities. The performance of quantitative CT angiography (QCTA) for identifying patients with myocardial perfusion defects remains unclear. CorE-64 is a multicenter, international study to assess the accuracy of 64-slice QCTA for detecting a parts per thousand yen50% coronary arterial stenoses by quantitative coronary angiography (QCA). Patients referred for cardiac catheterization with suspected or known coronary artery disease were enrolled. Area under the receiver-operating-characteristic curve (AUC) was used to evaluate the diagnostic accuracy of the most severe coronary artery stenosis in a subset of 63 patients assessed by QCTA and QCA for detecting myocardial perfusion abnormalities on exercise or pharmacologic stress SPECT. Diagnostic accuracy of QCTA for identifying patients with myocardial perfusion abnormalities by SPECT revealed an AUC of 0.71, compared to 0.72 by QCA (P = .75). AUC did not improve after excluding studies with fixed myocardial perfusion abnormalities and total coronary arterial occlusions. Optimal stenosis threshold for QCTA was 43% yielding a sensitivity of 0.81 and specificity of 0.50...

‣ Ganglioglioma with anaplastic transformation

Reis, Fabiano; Alves Vieira, Guilherme Henrique; Schwingel, Ricardo; Goncalves, Vinicius Trindade; Queiroz, Luciano de Souza
Fonte: Assoc Arquivos Neuro- Psiquiatria; Sao Paulo Publicador: Assoc Arquivos Neuro- Psiquiatria; Sao Paulo
Tipo: Artigo de Revista Científica
Português

‣ Semi-automatic determination of detailed vertebral shape from lumbar radiographs using active appearance models

Roberts, M. G.; Oh, T.; Pacheco, E. M. B.; Mohankumar, R.; Cootes, T. F.; Adams, J. E.
Fonte: Springer; London Publicador: Springer; London
Tipo: Artigo de Revista Científica
Português
The vertebral endplates in lumbar radiographs were located by a semi-automatic annotation method using statistical shape models. Vertebral fractures are common osteoporotic fractures, but current quantitative detection methods (morphometry) lack specificity. We have previously developed more specific quantitative classifiers of vertebral fracture using shape and appearance models. This method has only been applied to DXA vertebral fracture assessment (VFA) images and not to spinal radiographs. The classifiers require a detailed annotation of the outline of the vertebral endplate, so we investigated the application of similar semi-automated annotation methods to lumbar radiographs as the initial step in the generalisation of the statistical classifiers used in VFA images. The vertebral body outlines in a training set of 670 lumbar radiographs were manually annotated by expert radiologists. This training set was used to build statistical models of vertebral shape and appearance using triplets of vertebrae. In order to segment vertebrae, the models were refitted using a sequence of active appearance models of vertebral triplets, using a miss-40-out train/test cross-validation experiment. The accuracy was evaluated against the manual annotation and analysed by fracture grade. Good accuracy was obtained for normal vertebrae (0.82 mm) and fracture grades 1 and 2 (1.19 mm)...

‣ Effects of sex and locality on the abundance of lice on the wild rodent Oligoryzomys nigripes

Fernandes, Fernanda Rodrigues; Cruz, Leonardo Dominici; Linhares, Aricio Xavier
Fonte: Springer; New York Publicador: Springer; New York
Tipo: Artigo de Revista Científica
Português
Various factors can affect the parasite distribution on a host. In this study, the influence of sex, body size, and locality of a rodent host, Oligoryzomys nigripes, on lice abundance was investigated. A generalized linear model indicated that the sex and locality of O. nigripes significantly contributed to the variation in lice abundance on the host. The male bias of lice parasitizing the rodent host O. nigripes may be associated with intersexual differences in physiology and behavior, while locality differences in lice abundance may be associated with differences in host density and diversity between the two localities sampled. Studies of host-parasite associations improve the understanding of the ecology of infectious diseases, as well as the evolution of these host-parasite interactions.; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

‣ A new species of Yphthimoides (Lepidoptera: Nymphalidae: Satyrinae) from the southern Atlantic forest region

Freitas, Andre V. L.; Kaminski, Lucas A.; Mielke, Olaf H. H.; Barbosa, Eduardo P.; Silva-Brandao, Karina L.
Fonte: Magnolia Press; Auckland Publicador: Magnolia Press; Auckland
Tipo: Artigo de Revista Científica
Português
This paper describes a new, abundant and widespread species of Yphthimoides Forster from the Atlantic forests of southern Brazil, Paraguay, and northern Argentina (Misiones) in open and secondary vegetation and forest edges. Adult and immature stage morphology is described, molecular data are provided, and the placement of the new species within the genus Yphthimoides is discussed.; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

‣ Natural history of an ant-plant-butterfly interaction in a Neotropical savanna

Baechtold, Alexandra; Del-Claro, Kleber; Kaminski, Lucas A.; Freitas, Andre V. L.; Oliveira, Paulo S.
Fonte: Taylor & Francis; Abingdon Publicador: Taylor & Francis; Abingdon
Tipo: Artigo de Revista Científica
Português
Non-myrmecophilous lepidopteran larvae using plants bearing ant attractants such as extrafloral nectaries are good models for studying morphological and behavioural mechanisms against ant predation. Udranomia spitzi (Hesperiidae) is a butterfly whose larvae feed on leaves of Ouratea spectabilis (Ochnaceae), a plant with extrafloral nectaries. We described the early stages of U. spitzi, and used field observations and experiments to investigate the defensive strategies of caterpillars against predatory ants. Larvae pass through five instars and pupation occurs inside larval leaf shelters. Ant-exclusion experiments revealed that the presence of ants did not affect significantly caterpillar survival. Predation experiments showed that vulnerability to ant predation decreased with increase in larval size. The present study showed that predatory ants are not as relevant as demonstrated for other systems, and also illustrates how observational data and field experiments can contribute to a better understanding of the biology and ecology of a species of interest.; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

‣ Terrestrial Activity in Pitheciins (Cacajao, Chiropotes, and Pithecia)

Barnett, Adrian A.; Boyle, Sarah A.; Norconk, Marilyn M.; Palminteri, Suzanne; Santos, Ricardo R.; Veiga, Liza M.; Alvim, Thiago H. G.; Bowler, Mark; Chism, Janice; Di Fiore, Anthony; Fernandez-Duque, Eduardo; Guimaraes, Ana C. P.; Harrison-Levine, Amy; H
Fonte: Wiley-Blackwell; Hoboken Publicador: Wiley-Blackwell; Hoboken
Tipo: Artigo de Revista Científica
Português
Neotropical monkeys of the genera Cacajao, Chiropotes, and Pithecia (Pitheciidae) are considered to be highly arboreal, spending most of their time feeding and traveling in the upper canopy. Until now, the use of terrestrial substrates has not been analyzed in detail in this group. Here, we review the frequency of terrestrial use among pitheciin taxa to determine the ecological and social conditions that might lead to such behavior. We collated published and unpublished data from 14 taxa in the three genera. Data were gleaned from 53 published studies (including five on multiple pitheciin genera) and personal communications of unpublished data distributed across 31 localities. Terrestrial activity was reported in 61% of Pithecia field studies (11 of 18), in 34% of Chiropotes studies (10 of 29), and 36% of Cacajao studies (4 of 11). Within Pithecia, terrestrial behavior was more frequently reported in smaller species (e.g. P. pithecia) that are vertical clingers and leapers and make extensive use of the understory than in in the larger bodied canopy dwellers of the western Amazon (e.g. P. irrorata). Terrestrial behavior in Pithecia also occurred more frequently and lasted longer than in Cacajao or Chiropotes. An apparent association was found between flooded habitats and terrestrial activity and there is evidence of the development of a local pattern of terrestrial use in some populations. Seasonal fruit availability also may stimulate terrestrial behavior. Individuals also descended to the ground when visiting mineral licks...

‣ Phylogenetic and host-parasite relationship analysis of Henneguya multiplasmodialis n. sp infecting Pseudoplatystoma spp. in Brazilian Pantanal wetland

Adriano, E. A.; Carriero, M. M.; Maia, A. A. M.; Silva, M. R. M.; Naldoni, J.; Ceccarelli, P. S.; Arana, S.
Fonte: Elsevier; Amsterdam Publicador: Elsevier; Amsterdam
Tipo: Artigo de Revista Científica
Português
A new species of the genus Henneguya (Henneguya multiplasmodialis n. sp.) was found infecting the gills of three of 89 specimens (3.3%) of Pseudoplatystoma corruscans and two of 79 specimens (2.6%) of Pseudoplatystoma reticulatum from rivers in the Pantanal wetland, Brazil. Partial sequencing of the 18S rDNA gene of the spores obtained from one plasmodium from the gills of P. corruscans and other one from the gills of P. reticulatum, respectively, resulted in a total of 1560 and 1147 base pairs. As the spores of H. multiplasmodialis n. sp. resemble those of Henneguya corruscans, which is also a parasite of P. corruscans, sequencing of the 18S rDNA gene of the spores of H. corruscans found on P. corruscans caught in the Brazilian Pantanal wetland was also provided to avoid any taxonomic pendency between these two species, resulting in 1913 base pairs. The sequences of H. multiplasmodialis n. sp. parasite of P. corruscans and P. reticulatum and H. corruscans did not match any of the Myxozoa available in the GenBank. The similarity of H. multiplasmodialis n. sp. obtained from P. corruscans to that from P. reticulatum was of 99.7%. Phylogeny revealed a strong tendency among Henneguya species to form clades based on the order and/or family of the host fish. H. multiplasmodialis n. sp. clustered in a clade with Henneguya eirasi and H. corruscans...

‣ A new ectoparasitic Aulacothrips (Thysanoptera: Heterothripidae) from Amazon rainforest and the significance of variation in antennal sensoria

Cavalleri, Adriano; Kaminski, Lucas A.; Mendonca, Milton S., Jr.
Fonte: Magnolia Press; Auckland Publicador: Magnolia Press; Auckland
Tipo: Artigo de Revista Científica
Português
Aulacothrips amazonicus sp.n. is described from Northern Brazil, with larvae and adults ectoparasitic on ant-tended Membracidae (Hemiptera) on Solanum shrubs. This new taxon differs from its congeners by (i) body distinctively paler; (ii) sensoria on antennal segments III & IV much less convoluted; (iii) male tergite IX posterior margin straight and with several long and stout setae. The possible biological significance of interspecific differences in antennal sensoria among Aulacothrips species is discussed.; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

‣ Similarities among ectoparasite fauna of sigmodontine rodents: phylogenetic and geographical influences

Cruz, Leonardo Dominici; Fernandes, Fernanda Rodrigues; Linhares, Aricio Xavier
Fonte: Cambridge Univ Press; New York Publicador: Cambridge Univ Press; New York
Tipo: Artigo de Revista Científica
Português
Phylogenetic and geographical overlaps in host distributions influence the compositional similarity of ectoparasite fauna in a host-parasite system. In these systems, hosts that are more closely related (phylogenetically) are expected to share more parasitic species than more distantly related hosts. Similarly, hosts sharing a larger geographical distribution overlap are expected to have similar ectoparasites. This study investigated the influence of phylogeny (divergence time) and geographical overlap of some neotropical sigmodontine rodent species on the similarities among their ectoparasite fauna (Mesostigmata and Siphonaptera), using a partial Mantel test. Divergence time was the only significant factor that influenced the similarity among the ectoparasites, when mites and fleas were analysed together. Host species that had diverged more recently displayed ectoparasite fauna that were similar. The similarities of the flea species showed similar results in both separate and joint analyses, but neither phylogenetic nor geographical overlap influenced the similarity in mite species. Fleas were shown to be more host-specific than were mesostigmate mites, probably because of the increased influence of host phylogeny.; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

‣ Description of Rhodnius montenegrensis n. sp (Hemiptera: Reduviidae: Triatominae) from the state of Rondonia, Brazil

Da Rosa, Joao Aristeu; Rocha, Claudia Solano; Gardim, Sueli; Pinto, Mara Cristina; Mendonca, Vagner Jose; Rente Ferreira Filho, Julio Cesar; Costa De Carvalho, Elaine Oliveira; Aranha Camargo, Luis Marcelo; De Oliveira, Jader; Nascimento, Juliana Damieli;
Fonte: Magnolia Press; Auckland Publicador: Magnolia Press; Auckland
Tipo: Artigo de Revista Científica
Português
We present here a multisource approach that takes advantage of several disciplines to address a taxonomic issue. A triatomine related to Rhodnius robustus Larrousse, 1927 was recently found in the state of Rondonia, Brazil. The name Rhodnius montenegrensis n. sp. is suggested because it was found in the municipality of Monte Negro. The main differences between these two species can be detected in the female and male genitalia, but there are also noticeable differences in their eggs. Molecular analysis using PCR-RFLP technique and Bayesian inferences based on a fragment of the Cytochrome b (Cyt b) gene corroborated the morphological findings. We used this integrative approach to address the taxonomic decision for a new Rhodnius species and its relationship with others of this genus. Results obtained herein stress that morphology must be used as the major approach for obtaining phenotypic information, and molecular data should be taken as a complementary tool.; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

‣ Genetic diversity of avian paramyxovirus type 1: Proposal for a unified nomenclature and classification system of Newcastle disease virus genotypes

Diel, Diego G.; da Silva, Luciana H. A.; Liu, Hualei; Wang, Zhiliang; Miller, Patti J.; Afonso, Claudio L.
Fonte: Elsevier; Amsterdam Publicador: Elsevier; Amsterdam
Tipo: Artigo de Revista Científica
Português
The avian paramyxovirus type 1 (APMV-1), or Newcastle disease virus (NDV), comprise a diverse group of viruses with a single-stranded, negative-sense RNA genome. Historically, two systems have been simultaneously used to classify NOV isolates into lineages or genotypes, generating confusion in the nomenclature and discrepancies in the assignment of genetic groups. In the present study we assessed the genetic diversity of the avian paramyxovirus type-1 (APMV-1) and propose a unified nomenclature and a classification system based on objective criteria to separate NDV into genotypes. Complete F gene sequences of class I (n = 110) and class II (n = 602) viruses were used for the phylogenetic reconstruction and to identify distinct taxonomic groups. The mean interpopulational evolutionary distance was estimated (10%) and set as the cutoff value to assign new genotypes. Results of our study revealed that class I viruses comprise a single genotype, while class II contains 15 genetic groups including 10 previously established (I-IX, and XI) and five new genotypes (X, XII, XIII, XIV and XV). Sub-genotypes were identified among class I and class II genotypes. Adoption of a unified nomenclature and of objective criteria to classify NDV isolates will facilitate studies on NOV epidemiology...

‣ Comparing assemblages of Asteraceae and their insect herbivores under different land-use regimens

Diniz, Soraia; Lewinsohn, Thomas Michael; Prado, Paulo Inacio
Fonte: Wiley-Blackwell; Hoboken Publicador: Wiley-Blackwell; Hoboken
Tipo: Artigo de Revista Científica
Português
Accelerated tropical landscape changes occurring over recent decades have produced environmental mosaics comprising remaining isolated green areas and mixed land-use types. Our objective was to study the effects of alterations in the natural landscape on the species composition and structure of assemblages of Asteraceae and their endophagous insects through comparisons between cerrado (savanna), pastures and Eucalyptus stands. We first investigated whether similarities between assemblages of Asteraceae and their insects varied among land uses or localities. Secondly, we asked whether assemblages of Eucalyptus stands and pastures are subsets of those within the cerrado. We sampled within randomly deployed transects in 15 areas. Land use was found to be an important factor in determining plant composition similarity; however, locality did not exert any significant influence. Pastures were less similar to one another, suggesting high beta diversity. Similarities among insect assemblages were correlated with plant assemblage composition, but not with land use or locality. Species of Tephritidae were distributed along localities independently of land use. High beta diversity in Asteraceae assemblages among cerrados and pastures was supported by nestedness analysis. Plant assemblages in Eucalyptus stands were subsets of cerrado...

‣ CLEANING ASSOCIATIONS BETWEEN BIRDS AND HERBIVOROUS MAMMALS IN BRAZIL: STRUCTURE AND COMPLEXITY

Sazima, Cristina; Jordan, Pedro; Guimaraes, Paulo R., Jr.; Dos Reis, Sergio F.; Sazima, Ivan
Fonte: Amer Ornithologists Union; Lawrence Publicador: Amer Ornithologists Union; Lawrence
Tipo: Artigo de Revista Científica
Português
Birds that remove ectoparasites and other food material from their hosts are iconic illustrations of mutualistic-commensalistic cleaning associations. To assess the complex pattern of food resource use embedded in cleaning interactions of an assemblage of birds and their herbivorous mammal hosts in open habitats in Brazil, we used a network approach that characterized their patterns of association. Cleaning interactions showed a distinctly nested pattern, related to the number of interactions of cleaners and hosts and to the range of food types that each host species provided. Hosts that provided a wide range of food types (flies, ticks, tissue and blood, and organic debris) were attended by more species of cleaners and formed the core of the web. On the other hand, core cleaner species did not exploit the full range of available food resources, but used a variety of host species to exploit these resources instead. The structure that we found indicates that cleaners rely on cleaning interactions to obtain food types that would not be available otherwise (e.g., blood-engorged ticks or horseflies, wounded tissue). Additionally, a nested organization for the cleaner bird mammalian herbivore association means that both generalist and selective species take part in the interactions and that partners of selective species form an ordered subset of the partners of generalist species. The availability of predictable protein-rich food sources for birds provided by cleaning interactions may lead to an evolutionary pathway favoring their increased use by birds that forage opportunistically. Received 30 June 2011...

‣ Megadiverse developing countries face huge risks from invasives

Lovei, Gabor L.; Lewinsohn, Thomas. M.
Fonte: Elsevier; London Publicador: Elsevier; London
Tipo: Artigo de Revista Científica
Português

‣ Evaluation of tropical water sources and mollusks in southern Brazil using microbiological, biochemical, and chemical parameters

Marques Souza, Doris Sobral; Dores Ramos, Ana Paula; Nunes, Fabricio Flores; Moresco, Vanessa; Taniguchi, Satie; Guiguet Leal, Diego Averaldo; Sasaki, Silvio Tarou; Bicego, Marcia Caruso; Montone, Rosalinda Carmela; Durigan, Mauricio; Teixeira, Adriano Lu
Fonte: Elsevier; San Diego Publicador: Elsevier; San Diego
Tipo: Artigo de Revista Científica
Português
Florianopolis, a city located in the Santa Catarina State in southern Brazil, is the national leading producer of bivalve mollusks. The quality of bivalve mollusks is closely related to the sanitary conditions of surrounding waters where they are cultivated. Presently, cultivation areas receive large amounts of effluents derived mainly from treated and non-treated domestic, rural, and urban sewage. This contributes to the contamination of mollusks with trace metals, pesticides, other organic compounds, and human pathogens such as viruses, bacteria, and protozoan. The aim of this study was to perform a thorough diagnosis of the shellfish growing areas in Florianopolis, on the coast of Santa Catarina. The contamination levels of seawater, sediments, and oysters were evaluated for their microbiological, biochemical, and chemical parameters at five sea sites in Florianopolis, namely three regular oyster cultivation areas (Sites 1, 2, and oyster supplier), a polluted site (Site 3), and a heavily polluted site (Site 4). Samples were evaluated at day zero and after 14 days. Seawater and sediment samples were collected just once, at the end of the experiment. Antioxidant defenses, which may occur in contaminated environments in response to the increased production of reactive oxygen species (ROS) by organisms...

‣ Survival In Vitro and Virulence of Trypanosoma cruzi in Acai Pulp in Experimental Acute Chagas Disease

Barbosa, Rodrigo Labello; Dias, Viviane Liotti; Pereira, Karen Signori; Schmidt, Flavio Luis; Bueno Franco, Regina Maura; Aparecida Guaraldo, Ana Maria; Alves, Delma Pegolo; Correa Passos, Luiz Augusto
Fonte: Int Assoc Food Protection; Des Moines Publicador: Int Assoc Food Protection; Des Moines
Tipo: Artigo de Revista Científica
Português
Chagas disease is a parasitic infection with high socioeconomic impact throughout Latin America. Although this severe, incurable disease can be transmitted by several routes, oral transmission is currently the most important route in the Amazon Basin. Acai pulp has nutritional properties and is popular throughout Brazil and abroad. However, this pulp has been associated with microepidemics of acute Chagas disease (ACD) in northern Brazil, where agar fruit is the main food supplement. In this study, we examined the in vitro survival and in vivo virulence of Trypanosoma cruzi Y strain in acai pulp. Aliquots of in natura acai pulp produced in Belem city in the northern Brazilian state of Para were mixed with 10(5) trypomastigotes. The samples were incubated at room temperature or at 4 or 20 C for various periods, and the parasites were isolated by forced sieving. The resulting eluates were examined by microscopy, and the trypomastigotes were administered intraperitoneally, orally, or by gavage to immunodeficient mice (C.B-17-Prkdc(scid)/PasUnib) that had been pretreated with antibiotics. Parasitemia was quantified by the Brener method, and mortality was recorded daily. All routes of administration resulted in ACD. A 5-day delay in the onset of parasitemia occurred with oral administration. The survival and virulence of the parasites were unaffected by prior incubation at room temperature for 24 h...

‣ Thrombomodulin is required for the antithrombotic activity of thrombin mutant W215A/E217A in a mouse model of arterial thrombosis

Vicente, Cristina P.; Weiler, Hartmut; Di Cera, Enrico; Tollefsen, Douglas M.
Fonte: Pergamon-Elsevier Science Ltd; Oxford Publicador: Pergamon-Elsevier Science Ltd; Oxford
Tipo: Artigo de Revista Científica
Português
Introduction: The thrombin mutant W215A/E217A (WE thrombin) has greatly reduced procoagulant activity, but it activates protein C in the presence of thrombomodulin and inhibits binding of platelet glycoprotein Ib to von Willebrand factor and collagen under flow conditions. Both thrombomodulin-dependent protein C activation and inhibition of platelet adhesion could contribute to the antithrombotic activity of WE thrombin. Materials and methods: To assess the role of thrombomodulin, we administered WE thrombin to thrombomodulin-deficient (TMPro/Pro) mice and measured the time to occlusive thrombus formation in the carotid artery after photochemical injury of the endothelium. Results and conclusions: Doses of WE thrombin >= 10 mu g/kg prolonged the thrombosis time of wild-type mice (> 1.6-fold), while doses >= 100 mu g/kg only slightly prolonged the thrombosis time of TMPro/Pro mice. We conclude that thrombomodulin plays a predominate role in mediating the antithrombotic effect of WE thrombin in the arterial circulation of mice after endothelial injury. Thrombomodulin-independent effects may occur only when high doses of WE thrombin are administered. (c) 2011 Elsevier Ltd. All rights reserved.; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)