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101.
Silveira GF Meyer F Delfraro A Mosimann AL Coluchi N Vasquez C Probst CM Báfica A Bordignon J Dos Santos CN 《Journal of virology》2011,85(11):5374-5383
A recent (2007 to 2009) dengue outbreak caused by dengue virus (DENV) in Paraguay presented unusual severe clinical outcomes associated with 50% mortality rates. Although it has been reported that inflammatory responses influence the severity of dengue virus infection (T. Pang, M. J. Cardosa, and M. G. Guzman, Immunol. Cell Biol. 85:43-45, 2007), there remains a paucity of information on virus-innate immunity interactions influencing clinical outcome. Using human dendritic cells from a major innate immune cell population as an in vitro model, we have investigated signature cytokine responses as well as infectivity-replicative profiles of DENV clinical isolates from either a nonfatal case of classical dengue fever (strain DENV3/290; isolated in Brazil in 2002) or a fatal case of dengue fever with visceral complications isolated in Paraguay in 2007 (strain DENV3/5532). Strain DENV3/5532 was found to display significantly higher replicative ability than DENV3/290 in monocyte-derived dendritic cells (mdDCs). In addition, compared to DENV3/290 results, mdDCs exposed to DENV3/5532 showed increased production of proinflammatory cytokines associated with higher rates of programmed cell death, as shown by annexin V staining. The observed phenotype was due to viral replication, and tumor necrosis factor alpha (TNF-α) appears to exert a protective effect on virus-induced mdDC apoptosis. These results suggest that the DENV3/5532 strain isolated from the fatal case replicates within human dendritic cells, modulating cell survival and synthesis of inflammatory mediators. 相似文献
102.
103.
Kanae Sakai Plinio Trabasso Maria Luiza Moretti Yuzuru Mikami Katsuhiko Kamei Tohru Gonoi 《Mycopathologia》2014,178(1-2):11-26
The increasing incidence of infectious diseases caused by fungi in immunocompromised patients has encouraged researchers to develop rapid and accurate diagnosis methods. Identification of the causative fungal species is critical in deciding the appropriate treatment, but it is not easy to get satisfactory results due to the difficulty of fungal cultivation and morphological identification from clinical samples. In this study, we established a microarray system that can identify 42 species from 24 genera of clinically important fungal pathogens by using a chemical color reaction in the detection process. The array uses the internal transcribed spacer region of the rRNA gene for identification of fungal DNA at the species level. The specificity of this array was tested against a total of 355 target and nontarget fungal species. The fungal detection was succeeded directly from 103 CFU/ml for whole blood samples, and 50 fg DNA per 1 ml of serum samples indicating that the array system we established is sensitive to identify infecting fungi from clinical sample. Furthermore, we conducted isothermal amplification in place of PCR amplification and labeling. The successful identification with PCR-amplified as well as isothermally amplified target genes demonstrated that our microarray system is an efficient and robust method for identifying a variety of fungal species in a sample. 相似文献
104.
105.
André Rodrigues de Souza Luiza Carla Barbosa Martins Carlos Alberto Mourão-Júnior José Eduardo Serrão José Lino-Neto 《Journal of Insect Behavior》2014,27(2):251-256
Individual recognition (IR) has been demonstrated in some Pachycondyla ants. The maintenance of such memories is challenged when queens are separated for the few hours of forage (attenuation) or when they are simultaneously interacting with conspecifics in a reduced space, that is, the nest (interference). By quantifying the level of aggression among familiar and unfamiliar queens of P. inversa, we showed that memories of social partner’s identity are robust to attenuation over the course of 2 days and to interference from subsequent interaction with five other individuals. Because wasps and crabs also remember familiar partners after separation and interaction with other conspecifics, we propose that robustness of social memories is widespread in invertebrates with IR abilities. 相似文献
106.
Ana Luiza Freire Cintia Lacerda Ramos Euziclei Gonzaga de Almeida Whasley Ferreira Duarte Rosane Freitas Schwan 《World journal of microbiology & biotechnology》2014,30(2):567-577
Yakupa is a traditional non-alcoholic cassava beverage produced by Brazilian Amerindians. In this work the microbial dynamics and metabolites involved in yakupa fermentation were investigated by PCR-denaturing gradient gel electrophoresis and chromatography analysis, respectively. The lactic acid bacteria (LAB) population was higher than yeast in the beginning of fermentation (5 log CFU mL?1 and 3 log CFU mL?1, respectively) and after 36 h both population increased reaching 7 log CFU mL?1, remaining constant until 60 h. Culture dependent and independent methods in combination identified the bacteria Lactobacillus fermentum, L. plantarum, Weissela cibaria and W. confusa, and yeasts Saccharomyces cerevisiae and Pichia kudriavzevii. Maltose (41.2 g L?1), ethanol (6.5 g L?1) and lactic acid (7.8 g L?1) were the most abundant compounds identified by high performance liquid chromatography. Aldehydes, acids, alcohols and esters were identified by gas chromatography flame ionization detection. By the metabolites and PCA analysis we may assign the beverage’s flavor to the microbial metabolism. Heterolactic LAB and S. cerevisiae dominated the yakupa fermentation, being responsible for the organoleptic characteristics of the final product. This is the first time that the microbial dynamics and physicochemical parameters were investigated in the yakupa beverage and it may contribute to the future selection of starter cultures to perform yakupa fermentations. 相似文献
107.
108.
Luiza de Oliveira Saad Carlo Magenta Cunha Karine Delevati Colpo Ángel Valdés 《Helgoland Marine Research》2014,68(4):523-530
Species of sea hares have been recognized traditionally based on morphological traits, mainly the radula, external coloration, and reproductive anatomy. However, recent studies have shown substantial color variation in some sea slug species. Molecular data have been successfully used to differentiate morphologically similar species of “opisthobranchs” and resolve questions on the taxonomic value of color. The objective of this paper is to use molecular data in an attempt to elucidate whether specimens of Aplysia brasiliana with distinct colorations and morphologies are actually the same species. To this end, DNA from 14 specimens of A. brasiliana was extracted, including five specimens identified as a distinct morphotype from typical A. brasiliana. Although the two morphotypes have consistent differences in their external morphology and radula, the molecular data confirmed that there are no significant genetic differences between them. This is another example of the need to re-evaluate taxonomic decisions based on morphology in light of molecular evidence. 相似文献
109.
Studies on food preferences provide background information on the mechanisms that allow coexistence and resource exploitation among several species within the same system. In this study, we aimed to identify the trophic guild of chironomid larvae based on their feeding habits using gut content analysis. Larvae were collected using an Eckman-Birge grab in many areas of the subtropical Peri lagoon (southern Brazil) seasonally between March 2008 and April 2009. Null models were used to determine the frequency of co-occurrence of food items in the diets of chironomid larvae and to determine the frequency of co-occurrence of species belonging to a particular guild. Significant differences (seasonal or annual) were observed in patterns of co-occurrence of food items in the larval diets. Animal remains had a lower co-occurrence than would be expected as a result of chance, and plant items had a co-occurrence greater than would be expected by chance. The c scores for co-occurrence of species belonging to both predator and herbivore guilds revealed a higher co-occurrence of species than would be expected by chance. We suggest that the factors responsible for the results of this study were resource partitioning among species, habitat heterogeneity and resource availability in the environment. 相似文献
110.
Luiza O. Perucci Karina B. Gomes Letícia G. Freitas Lara C. Godoi Patrícia N. Alpoim Melina B. Pinheiro Aline S. Miranda Ant?nio L. Teixeira Luci M. Dusse Lirlandia P. Sousa 《PloS one》2014,9(5)