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21.
22.
Maruyama Fernanda Harumi de Paula Daphine Ariadne Jesus Menezes Isabela de Godoy Favalessa Olívia Cometti Hahn Rosane Christine de Almeida Arleana do Bom Parto Ferreira Sousa Valéria Régia Franco Nakazato Luciano Dutra Valéria 《Mycopathologia》2019,184(1):45-51
Mycopathologia - Cryptococcosis is caused by fungi of the genus Cryptococcus. Owing to its importance, this study aimed to analyze the genetic diversity of C. gattii isolates from animals, humans,... 相似文献
23.
Renata Priscila Barros de Menezes Jssika de Oliveira Viana Eugene Muratov Luciana Scotti Marcus Tullius Scotti 《Current issues in molecular biology》2022,44(1):383
Schistosomiasis is a chronic parasitic disease caused by trematodes of the genus Schistosoma; it is commonly caused by Schistosoma mansoni, which is transmitted by Bioamphalaria snails. Studies show that more than 200 million people are infected and that more than 90% of them live in Africa. Treatment with praziquantel has the best cost–benefit result on the market. However, hypersensitivity, allergy, and drug resistance are frequently presented after administration. From this perspective, ligand-based and structure-based virtual screening (VS) techniques were combined to select potentially active alkaloids against S. mansoni from an internal dataset (SistematX). A set of molecules with known activity against S. mansoni was selected from the ChEMBL database to create two different models with accuracy greater than 84%, enabling ligand-based VS of the alkaloid bank. Subsequently, structure-based VS was performed through molecular docking using four targets of the parasite. Finally, five consensus hits (i.e., five alkaloids with schistosomicidal potential), were selected. In addition, in silico evaluations of the metabolism, toxicity, and drug-like profile of these five selected alkaloids were carried out. Two of them, namely, 11,12-methylethylenedioxypropoxy and methyl-3-oxo-12-methoxy-n(1)-decarbomethoxy-14,15-didehydrochanofruticosinate, had plausible toxicity, metabolomics, and toxicity profiles. These two alkaloids could serve as starting points for the development of new schistosomicidal compounds based on natural products. 相似文献
24.
Neural networks learning with sliding mode control: the sliding mode backpropagation algorithm 总被引:1,自引:0,他引:1
Based on the classical backpropagation weight update equations, sliding mode control theory is introduced as a technique to adapt weights of a multi-layer perceptron. As will be demonstrated, the introduction of sliding mode has resulted in a much faster version of the standard backpropagation. The results show also that the proposed algorithm presents some important features of sliding mode control, which are robustness and high speed of learning. In addition to that, this paper shows also how control theory can be applied to train neural networks. 相似文献
25.
Landim RP de Menezes BR Silva SR Caminhas WM 《International journal of neural systems》1999,9(3):211-217
This work presents a Neo-Fuzzy-Neuron algorithm for the identification of nonlinear dynamic systems at the point of view of a rotor flux observer. The algorithm training is on-line, has low computational cost, does not require previous training and its convergence in one step is proved. The gradient descent method is used for its weights adjustment. Simulation and experimental results demonstrate the effectiveness of the algorithm for flux observer of induction motor drive system. 相似文献
26.
't Hoen PA Turk R Boer JM Sterrenburg E de Menezes RX van Ommen GJ den Dunnen JT 《Nucleic acids research》2004,32(4):e41
In two-colour microarrays, the ratio of signal intensities of two co-hybridized samples is used as a relative measure of gene expression. Ratio-based analysis becomes complicated and inefficient in multi-class comparisons. We therefore investigated the validity of an intensity-based analysis procedure. To this end, two different cRNA targets were hybridized together, separately, with a common reference and in a self-self fashion on spotted 65mer oligonucleotide microarrays. We found that the signal intensity of the cRNA targets was not influenced by the presence of a target labelled in the opposite colour. This indicates that targets do not compete for binding sites on the array, which is essential for intensity-based analysis. It is demonstrated that, for good-quality arrays, the correlation of signal intensity measurements between the different hybridization designs is high (R > 0.9). Furthermore, ratio calculations from ratio- and intensity-based analyses correlated well (R > 0.8). Based on these results, we advocate the use of separate intensities rather than ratios in the analysis of two-colour long-oligonucleotide microarrays. Intensity-based analysis makes microarray experiments more efficient and more flexible: It allows for direct comparisons between all hybridized samples, while circumventing the need for a reference sample that occupies half of the hybridization capacity. 相似文献
27.
Duarte AC Menezes AI Devens ES Roth JM Garcias GL Martino-Roth MG 《Genetics and molecular research : GMR》2004,3(2):288-292
Trisomy 13 is a clinically severe entity; 85% of the patients do not survive beyond one year, and most children die before completing six months of age. We report a female child, 28 months old, white, the fourth child of a non-consanguineous couple, who presented trisomy 13. The child was born at term, from a vaginal delivery, weighing 2600 g. At birth, she was cyanotic, icteric, spastic, and cried weakly. The initial clinical examination detected polydactyly in the left hand, congenital clubfoot and convex soles, ocular hypertelorism, a low nasal bridge, numerous hemangiomas distributed throughout the body, cardiomegaly, and perimembranous inter-ventricular communication. There was no cleft lip or palate. On physical examination at 18 months old, the child weighed 6,900 g, had a cephalic perimeter of 41 cm, a thoracic perimeter of 43 cm and was 76 cm tall. At 28 months, she weighed 10,760 g and was 88.5 cm tall. Neuropsychomotor development retardation was evident from birth and, according to the psychologist and the social assistant of APAE (Handicapped Parents and Friends Association) in Cangu?u, Rio Grande do Sul, there was a noticeable improvement after physiotherapy and recreational sessions. 相似文献
28.
Peripheral blood cytotoxic gammadelta T lymphocytes from patients with human immunodeficiency virus type 1 infection and AIDS lyse uninfected CD4+ T cells,and their cytocidal potential correlates with viral load 总被引:1,自引:0,他引:1
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Progression of human immunodeficiency virus type 1 (HIV-1) infection in humans is marked by declining CD4+-T-cell counts and increasing virus load (VL). Cytotoxic T lymphocytes (CTL) play an important role in the lysis of HIV-infected cells, especially during the early phase of asymptomatic infection. CTL responses in the later phase of disease progression may not be as effective since progressors with lower CD4+-T-cell counts have consistently higher VL despite having elevated CTL counts. We hypothesized that, apart from antiviral effects, some CTL might also contribute to AIDS pathogenesis by depleting CD4+ T cells and that this CTL activity may correlate with the VL in AIDS patients. Therefore, a cross-sectional study of 31 HIV-1-infected patients at various clinical stages was carried out. Purified CTL from these donors as well as HIV-seronegative controls were used as effectors against different human cell targets by using standard 51Cr release cytolytic assays. A direct correlation between VL and CTL-mediated, major histocompatibility complex (MHC)-unrestricted lysis of primary CD4+-T-cell, CEM.NKR, and K562 targets was observed. CD4+-T-cell counts and duration of infection also correlated with MHC-unrestricted cytolytic activity. Our data clearly show that gammadelta CTL are abnormally expanded in the peripheral blood of HIV-infected patients and that the Vdelta1 subset of gammadelta T cells is the main effector population responsible for this type of cytolysis. The present data suggest that gammadelta CTL can contribute to the depletion of bystander CD4+ T cells in HIV-infected patients as a parallel mechanism to HIV-associated immunopathogenesis and hence expedite AIDS progression. 相似文献
29.
Menezes CM Kirchgatter K Di Santi SM Savalli C Monteiro FG Paula GA Ferreira EI 《Memórias do Instituto Oswaldo Cruz》2002,97(7):1033-1039
Phenothiazine drugs - fluphenazine, chlorpromazine, methotrimeprazine and trifluoperazine - were evaluated as modulating agents against Brazilian chloroquine-resistant fresh isolates of Plasmodium falciparum. Aiming to simulate therapeutic schedules, chloroquine was employed at the concentration used for sensitive falciparum malaria treatment and anti-psychotic therapeutic concentrations of the phenothiazine drugs were adopted in two-fold serial dilutions. The in vitro microtechnique for drug susceptibility was employed. Unlike earlier reported data, the phenothiazine modulating effect was not observed. However, all the drugs demonstrated intrinsic antiplasmodial activity in concentrations lower than those described in the literature. In addition, IC50 estimates have been shown to be inferior to the usual anti-psychotic therapeutic concentrations. Statistical analysis also suggested an increase in the parasitaemia rate or, even, a predominant antiparasitic effect of phenothiazine over chloroquine when used in combination. 相似文献
30.
Preferential localization of the Epstein-Barr virus (EBV) oncoprotein LMP-1 to nuclei in human T cells: implications for its role in the development of EBV genome-positive T-cell lymphomas 总被引:1,自引:0,他引:1
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The Epstein-Barr virus (EBV)-encoded latent membrane protein-1 (LMP-1) is thought to play a role in the EBV-induced B-cell transformation and immortalization. EBV has also been implicated in certain human T-cell lymphomas; however, the phenotypic effects of the expression of this oncoprotein in T cells are not known. To learn whether LMP-1 also induces phenotypic changes in T cells, we stably expressed it in human cell lines of T and B lineages and 25 LMP-1-expressing T-cell clones and 7 B-cell clones were examined. Our results show for the first time that, in sharp contrast to B cells, LMP-1 preferentially localizes to nuclei in T cells and does not induce the phenotypic changes in these cells that it induces in B cells, does not associate with TRAF proteins, and does not arrest the cell cycle in the G2/M phase. A computer-assisted analysis revealed that LMP-1 lacks the canonical nuclear localization signal. Our results suggest that this oncoprotein may not play the same role in the lymphomagenesis of T cells as it does in B cells. 相似文献