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891.
Tuon FF 《Revista iberoamericana de micología》2007,24(2):89-94
Polymerase chain reaction (PCR) from bronchoalveolar lavage clinical samples (BAL) has been used to assist in the diagnosis of invasive aspergillosis. Several studies have been published regarding the utility of this test, although no systematic review of the literature has been performed to date. The objective of this systematic review was to evaluate the efficacy of PCR from BAL for the diagnosis of invasive aspergillosis in high risk patients. MEDLINE and LILACS databases (1980-2006) searches to identify articles related to PCR in diagnosis of invasive aspergillosis. For inclusion, the study had to report sufficient data to calculate sensitivity, specificity and diagnostic odds ratio of the PCR-based technique. Patients with proven and probably invasive aspergillosis were considered. Forty-five articles met our initial inclusion criteria of which 15 articles were selected. Combining the results from the different reports, the overall sensitivity and specificity values of PCR-based techniques were 79% and 94%, respectively. Contamination, specific primers and method of PCR were important variables that could complicate interpretation of these tests. The present study showed support for the clinical value of PCR from BAL for the diagnosis of invasive aspergillosis in patients with risk factors for this disease. 相似文献
892.
893.
Marcus de Melo Teixeira Anderson Messias Rodrigues Clement K. M. Tsui Luiz Gonzaga Paulo de Almeida Anne D. Van Diepeningen Bert Gerrits van den Ende Geisa Ferreira Fernandes Rui Kano Richard C. Hamelin Leila Maria Lopes-Bezerra Ana Tereza Ribeiro Vasconcelos Sybren de Hoog Zoilo Pires de Camargo Maria Sueli Soares Felipe 《Eukaryotic cell》2015,14(2):158-169
Sporotrichosis is one of the most frequent subcutaneous fungal infections in humans and animals caused by members of the plant-associated, dimorphic genus Sporothrix. Three of the four medically important Sporothrix species found in Brazil have been considered asexual as no sexual stage has ever been reported in Sporothrix schenckii, Sporothrix brasiliensis, or Sporothrix globosa. We have identified the mating type (MAT) loci in the S. schenckii (strain 1099-18/ATCC MYA-4821) and S. brasiliensis (strain 5110/ATCC MYA-4823) genomes by using comparative genomic approaches to determine the mating type ratio in these pathogen populations. Our analysis revealed the presence of a MAT1-1 locus in S. schenckii while a MAT1-2 locus was found in S. brasiliensis representing genomic synteny to other Sordariomycetes. Furthermore, the components of the mitogen-activated protein kinase (MAPK)-pheromone pathway, pheromone processing enzymes, and meiotic regulators have also been identified in the two pathogens, suggesting the potential for sexual reproduction. The ratio of MAT1-1 to MAT1-2 was not significantly different from 1:1 for all three Sporothrix species, but the population of S. brasiliensis in the outbreaks originated from a single mating type. We also explored the population genetic structure of these pathogens using sequence data of two loci to improve our knowledge of the pattern of geographic distribution, genetic variation, and virulence phenotypes. Population genetics data showed significant population differentiation and clonality with a low level of haplotype diversity in S. brasiliensis isolates from different regions of sporotrichosis outbreaks in Brazil. In contrast, S. schenckii isolates demonstrated a high degree of genetic variability without significant geographic differentiation, indicating the presence of recombination. This study demonstrated that two species causing the same disease have contrasting reproductive strategies and genetic variability patterns. 相似文献
894.
Helmuth Aguirre Luis Felipe de Almeida Scott Richard Shaw Carlos E. Sarmiento 《ZooKeys》2015,(489):33-94
A comprehensive key for 75 species of Meteorus distributed across 15 Neotropical countries is presented. Eleven new species from Bolivia, Costa Rica and Ecuador are described: Meteorus
albistigma, Meteorus
carolae, Meteorus
eurysaccavorus, Meteorus
fallacavus, Meteorus
flavistigma, Meteorus
haimowitzi, Meteorus
magnoculus, Meteorus
martinezi, Meteorus
microcavus, Meteorus
noctuivorus and Meteorus
orion. Expanded range distributions are recorded for Meteorus
andreae, Meteorus
farallonensis, Meteorus
guineverae, Meteorus
jerodi, Meteorus
kraussi, Meteorus
papiliovorus and Meteorus
quimbayensis. The host of Meteorus
jerodi is reported for the first time: a noctuid larva feeding on Asteraceae. Meteorus
papiliovorus is recorded attacking Papilionidae larvae in Ecuador, therefore displaying a similar host family preference as formerly documented from Costa Rica and Colombia. 相似文献
895.
Marraccini P Vinecky F Alves GS Ramos HJ Elbelt S Vieira NG Carneiro FA Sujii PS Alekcevetch JC Silva VA DaMatta FM Ferrão MA Leroy T Pot D Vieira LG da Silva FR Andrade AC 《Journal of experimental botany》2012,63(11):4191-4212
The aim of this study was to investigate the molecular mechanisms underlying drought acclimation in coffee plants by the identification of candidate genes (CGs) using different approaches. The first approach used the data generated during the Brazilian Coffee expressed sequence tag (EST) project to select 13 CGs by an in silico analysis (electronic northern). The second approach was based on screening macroarrays spotted with plasmid DNA (coffee ESTs) with separate hybridizations using leaf cDNA probes from drought-tolerant and susceptible clones of Coffea canephora var. Conilon, grown under different water regimes. This allowed the isolation of seven additional CGs. The third approach used two-dimensional gel electrophoresis to identify proteins displaying differential accumulation in leaves of drought-tolerant and susceptible clones of C. canephora. Six of them were characterized by MALDI-TOF-MS/MS (matrix-assisted laser desorption-time of flight-tandem mass spectrometry) and the corresponding proteins were identified. Finally, additional CGs were selected from the literature, and quantitative real-time polymerase chain reaction (qPCR) was performed to analyse the expression of all identified CGs. Altogether, >40 genes presenting differential gene expression during drought acclimation were identified, some of them showing different expression profiles between drought-tolerant and susceptible clones. Based on the obtained results, it can be concluded that factors involved a complex network of responses probably involving the abscisic signalling pathway and nitric oxide are major molecular determinants that might explain the better efficiency in controlling stomata closure and transpiration displayed by drought-tolerant clones of C. canephora. 相似文献
896.
Melo T Videira RA André S Maciel E Francisco CS Oliveira-Campos AM Rodrigues LM Domingues MR Peixoto F Manuel Oliveira M 《Journal of neurochemistry》2012,120(6):998-1013
Tacrine is an acetylcholinesterase (AChE) inhibitor used as a cognitive enhancer in the treatment of Alzheimer's disease (AD). However, its low therapeutic efficiency and a high incidence of side effects have limited its clinical use. In this study, the molecular mechanisms underlying the impact on brain activity of tacrine and two novel tacrine analogues (T1, T2) were approached by focusing on three aspects: (i) their effects on brain cholinesterase activity; (ii) perturbations on electron transport chain enzymes activities of non-synaptic brain mitochondria; and (iii) the role of mitochondrial lipidome changes induced by these compounds on mitochondrial bioenergetics. Brain effects were evaluated 18 h after the administration of a single dose (75.6 μmol/kg) of tacrine or tacrine analogues. The three compounds promoted a significant reduction in brain AChE and butyrylcholinesterase (BuChE) activities. Additionally, tacrine was shown to be more efficient in brain AChE inhibition than T2 tacrine analogue and less active than T1 tacrine analogue, whereas BuChE inhibition followed the order: T1 > T2 > tacrine. The studies using non-synaptic brain mitochondria show that all the compounds studied disturbed brain mitochondrial bioenergetics mainly via the inhibition of complex I activity. Furthermore, the activity of complex IV is also affected by tacrine and T1 treatments while FoF(1) -ATPase is only affected by tacrine. Therefore, the compounds' toxicity as regards brain mitochondria, which follows the order: tacrine > T1 > T2, does not correlate with their ability to inhibit brain cholinesterase enzymes. Lipidomics approaches show that phosphatidylethanolamine (PE) is the most abundant phospholipids (PL) class in non-synaptic brain mitochondria and cardiolipin (CL) present the greatest diversity of molecular species. Tacrine induced significant perturbations in the mitochondrial PL profile, which were detected by means of changes in the relative abundance of phosphatidylcholine (PC), PE, phosphatidylinositol (PI) and CL and by the presence of oxidized phosphatidylserines. Additionally, in both the T1 and T2 groups, the lipid content and molecular composition of brain mitochondria PL are perturbed to a lesser extent than in the tacrine group. Abnormalities in CL content and the amount of oxidized phosphatidylserines were associated with significant reductions in mitochondrial enzymes activities, mainly complex I. These results indicate that tacrine and its analogues impair mitochondrial function and bioenergetics, thus compromising the activity of brain cells. 相似文献
897.
The helminth community of Tropidurus torquatus (Squamata: Tropiduridae) from a rocky outcrop area located in the state of Minas Gerais, southeastern Brazil, was studied. Ninety-two of the 110 individuals examined (83.6%) harbored helminths. Five species were found, including 3 nematodes ( Physaloptera lutzi , Parapharyngodon bainae , and Oswaldofilaria chabaudi ), 1 unidentified cestode species, and 1 acanthocephalan cystacanth also not identified. Only the nematode species had sufficient data to perform ecological analysis, with P. lutzi exhibiting the highest prevalence (67.3%). Prevalence between male and female hosts differed only for Oswaldofilaria chabaudi , with males exhibiting the highest values. The intensities of infection by P. lutzi and O. chabaudi were different among male and female hosts, with males also exhibiting the highest values. The host body size was positively related to intensity of infection for all nematode species. Local seasonality had some influence on the helminth community structure. Host diet, sexual dimorphism, and behavior (territorialism, forage strategy) represented important factors for the structure of this parasite community. In general, the helminth community was species poor, depauperate, and non-interactive, representing a typical structure observed in lizard hosts. 相似文献
898.
Valle-Casuso JC Di Nunzio F Yang Y Reszka N Lienlaf M Arhel N Perez P Brass AL Diaz-Griffero F 《Journal of virology》2012,86(10):5931-5936
TNPO3 is a nuclear importer required for HIV-1 infection. Here, we show that depletion of TNPO3 leads to an HIV-1 block after nuclear import but prior to integration. To investigate the mechanistic requirement of TNPO3 in HIV-1 infection, we tested the binding of TNPO3 to the HIV-1 core and found that TNPO3 binds to the HIV-1 core. Overall, this work suggests that TNPO3 interacts with the incoming HIV-1 core in the cytoplasm to assist a process that is important for HIV-1 infection after nuclear import. 相似文献
899.
Marroig G Melo DA Garcia G 《Evolution; international journal of organic evolution》2012,66(5):1506-1524
Most biological systems are formed by component parts that are to some degree interrelated. Groups of parts that are more associated among themselves and are relatively autonomous from others are called modules. One of the consequences of modularity is that biological systems usually present an unequal distribution of the genetic variation among traits. Estimating the covariance matrix that describes these systems is a difficult problem due to a number of factors such as poor sample sizes and measurement errors. We show that this problem will be exacerbated whenever matrix inversion is required, as in directional selection reconstruction analysis. We explore the consequences of varying degrees of modularity and signal-to-noise ratio on selection reconstruction. We then present and test the efficiency of available methods for controlling noise in matrix estimates. In our simulations, controlling matrices for noise vastly improves the reconstruction of selection gradients. We also perform an analysis of selection gradients reconstruction over a New World Monkeys skull database to illustrate the impact of noise on such analyses. Noise-controlled estimates render far more plausible interpretations that are in full agreement with previous results. 相似文献
900.
Gomes LI Gonzaga FM de Morais-Teixeira E de Souza-Lima BS Freire VV Rabello A 《Experimental parasitology》2012,131(2):175-179
In vitro assays play an important role in the discovery and development of new antileishmanial drugs. The classic macrophage-amastigote models using murine peritoneal macrophages or human-monocyte derived macrophages as host cells are useful for drug screening. A major limitation of these models is the dependence on microscopic counting, a time-consuming and subjective method of analysis. The present study describes a detailed protocol for applying quantitative real-time PCR (qPCR) as an accurate and sensitive tool to assess parasite load in an amastigote-macrophage model. This assay can be performed in a standardized medium-to-high throughput procedure, replacing traditional readout of number of amastigote per macrophages by DNA load measurement. 相似文献