242 research outputs found
Functional Diversity of the Schistosoma mansoni Tyrosine Kinases
Schistosoma mansoni, one of the causative agents of schistosomiasis, has a complex life cycle infecting over 200 million people worldwide. Such a successful and prolific parasite life cycle has been shown to be dependent on the adaptive interaction between the parasite and hosts. Tyrosine kinases (TKs) play a key role in signaling pathways as demonstrated by a large body of experimental work in eukaryotes. Furthermore, comparative genomics have allowed the identification of TK homologs and provided insights into the functional role of TKs in several biological systems. Finally, TK structural biology has provided a rational basis for obtaining selective inhibitors directed to the treatment of human diseases. This paper covers the important aspects of the phospho-tyrosine signaling network in S. mansoni, Caenorhabditis elegans, and humans, the main process of functional diversification of TKs, that is, protein-domain shuffling, and also discusses TKs as targets for the development of new anti-schistosome drugs
AnĂĄlise da variabilidade espacial da ocorrĂȘncia do bicho-mineiro [Leucoptera coffeella, (GUĂR.-MĂNEV., 1942)] (Lepidoptera: Lyonetiidae) em cafezal (Coffea arĂĄbica, L.) orgĂąnico em formação.
Um dos desafios na produção orgĂąnica de cafĂ© Ă© o controle de pragas sem o uso de pesticidas. Uma das pragas mais prejudiciais Ă© o bicho-mineiro (Leucoptera coffeella), que pode causar severos danos aos cafeeiros, com perdas que podem alcançar 50% da produção total. Compreender a distribuição espacial do bicho-mineiro pode ser importante no contexto do controle biolĂłgico da praga. O objetivo deste trabalho foi caracterizar o relacionamento entre a presença do bicho-mineiro e a localização do cafeeiro (Coffea arabica) em um cultivo orgĂąnico no segundo ano de sua implantação. Foi usado o semivariograma como uma ferramenta para a determinação do grau de dependĂȘncia espacial do bicho-mineiro. Pelos resultados obtidos, podemos afirmar que a ocorrĂȘncia do bicho-mineiro apresenta autocorrelação espacial atĂ© 30 metros
Distribuição espacial do bicho-mineiro, Leucoptera coffeella (Guér.-Ménev., 1942)(Lepidoptera: Lyonetiidae), e vespas (Hymenoptera: vespidae) em cafezal (Coffea arabica L.) orgùnico em formação.
O bicho-mineiro do cafeeiro [Leucoptera coffeella (GuĂ©r.-MĂšnev., 1942).] Ă© uma das maiores pragas dos cafezais, acarretando perdas de atĂ© 50% na produção. O conhecimento da distribuição espacial dessa praga e das vespas (Hymenoptera: Vespidae), seus predadores, Ă© muito importante para seu melhor manejo em plantaçÔes de cafĂ© orgĂąnico. Neste trabalho foi estudado um cafezal orgĂąnico em formação no seu terceiro ano de implantação. Foram utilizados os Ăndices de Fisher e Morisita para caracterizar a distribuição espacial do numero de folhas minadas, numero de minas novas, nĂșmero de minas predadas e nĂșmero de vespas. Os intervalos de confiança para os Ăndices foram calculados utilizando o mĂ©todo bootstrap. Os Ăndices nĂŁo conseguiram identificar claramente um padrĂŁo espacial para as variĂĄveis no perĂodo investigado
Cerebral vasomotor reactivity assessment using transcranial doppler and MRI with apnea test
CNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTĂFICO E TECNOLĂGICOFAPESP - FUNDAĂĂO DE AMPARO Ă PESQUISA DO ESTADO DE SĂO PAULODifferently from previous studies that used Transcranial Doppler (TCD) and functional MRI (fMRI) for cerebral vasomotor reactivity (CVR) assessment in patients with carotid stenosis (CS), we assessed CVR using an identical stimulus, the Breath-Holding Test (BHT). We included 15 patients with CS and 7 age-matched controls to verify whether fMRI responded differently to BHT between groups and to calculate the agreement rate between tests. For TCD, impaired CVR was defined when the mean percentage increase on middle cerebral artery velocities was p31% on 3 consecutive 30-s apnea intercalated by 4-min normal breathing intervals. For fMRI, the percent variation on blood oxygen level-dependent (BOLD) signal intensity in the lentiform nucleus (LN) ipsilateral to the CS (or both LNs for controls) from baseline breathing to apnea was measured. The Euclidian differences between the series of each subject and the series of controls and patients classified it into normal or impaired CVR. We found different percent variations on BOLD-signal intensities between groups (P=0.032). The agreement was good in Controls (85.7%; kappa=0.69) and overall (77.3%; kappa=0.54). We conclude that BHT was feasible for CVR assessment on fMRI and elicited different BOLD responses in patients and controls, with a good overall agreement between the tests.Differently from previous studies that used Transcranial Doppler (TCD) and functional MRI (fMRI) for cerebral vasomotor reactivity (CVR) assessment in patients with carotid stenosis (CS), we assessed CVR using an identical stimulus, the Breath-Holding Test (BHT). We included 15 patients with CS and 7 age-matched controls to verify whether fMRI responded differently to BHT between groups and to calculate the agreement rate between tests. For TCD, impaired CVR was defined when the mean percentage increase on middle cerebral artery velocities was p31% on 3 consecutive 30-s apnea intercalated by 4-min normal breathing intervals. For fMRI, the percent variation on blood oxygen level-dependent (BOLD) signal intensity in the lentiform nucleus (LN) ipsilateral to the CS (or both LNs for controls) from baseline breathing to apnea was measured. The Euclidian differences between the series of each subject and the series of controls and patients classified it into normal or impaired CVR. We found different percent variations on BOLD-signal intensities between groups (P=0.032). The agreement was good in Controls (85.7%, kappa=0.69) and overall (77.3%, kappa=0.54). We conclude that BHT was feasible for CVR assessment on fMRI and elicited different BOLD responses in patients and controls, with a good overall agreement between the tests.491118CNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTĂFICO E TECNOLĂGICOFAPESP - FUNDAĂĂO DE AMPARO Ă PESQUISA DO ESTADO DE SĂO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTĂFICO E TECNOLĂGICOFAPESP - FUNDAĂĂO DE AMPARO Ă PESQUISA DO ESTADO DE SĂO PAULO2010/52027-1, 2013/07559-3480976/2010-4The institutional support of Prof. Fernando Cendes and the Neurovascular Study Group, as well as the kind assistance of Ms. Isilda Assumpcao (RN) and team, are gratefully acknowledged. This research was supported by FAPESP (Process 2010/52027-1 and 2013/07559-3) and CNPq (Process 480976/2010-4)
Spatial variability of soil fertility attributes and productivity in a coffee crop farm
ArticleCoffee cultivation is of great importance to Brazilian agribusiness, as coffee occupies
extensive production areas and is one of the most exported Brazilian products. To maintain coffee
production numbers, productive techniques must be adopted that optimize productive system use.
The objective of this work was to apply geostatistical techniques in the evaluation of soil fertility
attributes to construct maps of variability in soil fertility parameters and the productivity of a
coffee crop in the municipality of Monte Carmelo, Minas Gerais (MG), Brazil. The work was
developed with coffee of the cultivar Mundo Novo 379/19, and 19 sample points were
georeferenced in Universal Transverse Mercator coordinates. Spatial dependence of the fertility
and productivity parameters was analysed via classic semivariogram fitting and interpolation by
ordinary kriging using the statistical computer system, R. All parameters evaluated showed high
degrees of spatial dependence. The attribute values varied along the sampling points, except for
the sodium (Na) contents, which had similar values in all samplings. The studied parameters
ranged from 80 to 200 metres. It is conclusion, the use of productivity maps linked to soil
chemical attributes can be useful for determining the occurrence of variable productivity rates
throughout the area, allowing the adoption of corrective practices for subsequent crops and thus
making the maps very useful tools for producers
Hole burning in a nanomechanical resonator coupled to a Cooper pair box
We propose a scheme to create holes in the statistical distribution of
excitations of a nanomechanical resonator. It employs a controllable coupling
between this system and a Cooper pair box. The success probability and the
fidelity are calculated and compared with those obtained in the atom-field
system via distinct schemes. As an application we show how to use the
hole-burning scheme to prepare (low excited) Fock states.Comment: 7 pages, 10 figure
Regulatory T Cells Phenotype in Different Clinical Forms of Chagas' Disease
CD25High CD4+ regulatory T cells (Treg cells) have been described as key players in immune regulation, preventing infection-induced immune pathology and limiting collateral tissue damage caused by vigorous anti-parasite immune response. In this review, we summarize data obtained by the investigation of Treg cells in different clinical forms of Chagas' disease. Ex vivo immunophenotyping of whole blood, as well as after stimulation with Trypanosoma cruzi antigens, demonstrated that individuals in the indeterminate (IND) clinical form of the disease have a higher frequency of Treg cells, suggesting that an expansion of those cells could be beneficial, possibly by limiting strong cytotoxic activity and tissue damage. Additional analysis demonstrated an activated status of Treg cells based on low expression of CD62L and high expression of CD40L, CD69, and CD54 by cells from all chagasic patients after T. cruzi antigenic stimulation. Moreover, there was an increase in the frequency of the population of Foxp3+ CD25HighCD4+ cells that was also IL-10+ in the IND group, whereas in the cardiac (CARD) group, there was an increase in the percentage of Foxp3+ CD25High CD4+ cells that expressed CTLA-4. These data suggest that IL-10 produced by Treg cells is effective in controlling disease development in IND patients. However, in CARD patients, the same regulatory mechanism, mediated by IL-10 and CTLA-4 expression is unlikely to be sufficient to control the progression of the disease. These data suggest that Treg cells may play an important role in controlling the immune response in Chagas' disease and the balance between regulatory and effector T cells may be important for the progression and development of the disease. Additional detailed analysis of the mechanisms on how these cells are activated and exert their function will certainly give insights for the rational design of procedure to achieve the appropriate balance between protection and pathology during parasite infections
Avaliação da resistĂȘncia ao cisalhamento da uniĂŁo entre duas ligas a base de CoCr e uma cerĂąmica
INTRODUCTION: Based on the importance of the integrity of the metal/ceramic interface, the purpose of this work was to
evaluate the shear bond strength of the metal-ceramic union of two Co-Cr alloys (Wirobond C, Bego; Remanium 2000, Dentaurum)
combined with Omega 900 ceramic (Vita Zahnfabrik). MATERIAL and METHOD: Eleven cylindrical matrixes were made for
each alloy, and the metallic portion was obtained with the lost wax casting technique with standardized waxing of 4mm of height
and of 4mm of diameter. The ceramic was applied according to the manufacturerâs recommendations with the aid of a teflon
matrix that allowed its dimension to be standardized in the same size as the metallic portion. The specimens were submitted to
the shear bond test in an universal testing machine (EMIC), with the aid of a device developed for such intention, and constant
speed of 0.5mm/min. RESULTS and CONCLUSIONS: The mean resistance was 48.387MPa for Wirobond C alloy, with standard
deviation of 17.718, and 55.956MPa for Remanium 2000, with standard deviation of 17.198. No statistically significant difference
was observed between the shear strength of the two metal-ceramic alloys. ______________________________________________________________________________________________________________ RESUMOINTRODUĂĂO: Baseados na importĂąncia da integridade da interface metal-cerĂąmica, este trabalho tem como objetivo
avaliar a resistĂȘncia ao cisalhamento da uniĂŁo metal-cerĂąmica de duas ligas de Co-Cr (Wirobond C, Bego; Remanium 2000,
Dentaurum) combinadas com a cerĂąmica Omega 900 (Vita Zahnfabrik). MATERIAIS E MĂTODOS: Foram confeccionados 11
corpos-de-prova cilĂndricos para cada liga utilizada, sendo que a porção metĂĄlica foi obtida por fundição pela tĂ©cnica da cera
perdida, através de enceramentos padronizados com 4mm de altura por 4mm de diùmetro. A aplicação da cerùmica foi realizada
segundo recomendaçÔes do fabricante, com auxĂlio de uma matriz de teflon que permitia sua padronização com as mesmas
dimensĂ”es da porção metĂĄlica. Os corpos-de-prova foram submetidos ao ensaio de resistĂȘncia ao cisalhamento em mĂĄquina de
ensaios universal (EMIC), com auxĂlio de dispositivo desenvolvido para tal propĂłsito, sob velocidade constante de 0,5mm/
min. RESULTADOS E CONCLUSĂES: As mĂ©dias de resistĂȘncia obtidas foram 48,387 MPa para a liga Wirobond C, com desvio
padrĂŁo de 17,718, e 55,956 MPa para a Remanium 2000, com desvio padrĂŁo de 17,198. ApĂłs anĂĄlise de variĂąncia foi possĂvel
observar que nĂŁo hĂĄ diferença estatisticamente significante entre os valores de resistĂȘncia ao cisalhamento das duas ligas
metalocerĂąmicas
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