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Search Results: 1 - 10 of 488969 matches for " Alda M. T. Ferreira "
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Genetic and antigenic analysis of Babesia bigemina isolates from five geographical regions of Brazil
Madruga Claudio R.,Leal Cássia R.B.,Ferreira Alda M.T.,Araújo Flábio R.
Pesquisa Veterinária Brasileira , 2002,
Abstract: A molecular epidemiological study was performed with Babesia bigemina isolates from five geographical regions of Brazil. The genetic analysis was done with random amplification of polymorphic DNA (RAPD), repetitive extragenic palindromic elements-polymerase chain reaction (REP-PCR) and enterobacterial repetitive intergenic consensus sequences-polymerase chain reaction (ERIC-PCR) that showed genetic polymorphism between these isolates and generated fingerprinting. In RAPD, ILO872 and ILO876 primers were able to detect at least one fingerprinting for each B. bigemina isolate. The amplification of B. bigemina DNA fragments by REP-PCR and ERIC-PCR gave evidence for the presence in this haemoprotozoan of the sequences described previously in microorganisms of the bacterial kingdom. For the first time it was demonstrated that both techniques can be used for genetic analysis of a protozoan parasite, although the ERIC-PCR was more discriminatory than REP-PCR. The dendogram with similarity coefficient among isolates showed two clusters and one subcluster. The Northeastern and Mid-Western isolates showed the greatest genetic diversity, while the Southeastern and Southern isolates were the closest. The antigenic analysis was done through indirect fluorescent antibody technique and Western blotting using a panel of monoclonal antibodies directed against epitopes on the merozoite membrane surface, rhoptries and membrane of infected erythrocytes. As expected, the merozoite variable surface antigens, major surface antigen (MSA)-1 and MSA-2 showed antigenic diversity. However, B cell epitopes on rhoptries and infected erythrocytes were conserved among all isolates studied. In this study it was possible to identify variable and conserved antigens, which had already been described as potential immunogens. Considering that an attenuated Babesia clone used as immunogen selected populations capable of evading the immunity induced by this vaccine, it is necessary to evaluate more deeply the cross-protection conferred by genetically more distant Brazilian B. bigemina isolates and make an evaluation of the polymorphism degree of variable antigens such as MSA-1 and MSA-2.
Genetic and antigenic analysis of Babesia bigemina isolates from five geographical regions of Brazil
Madruga, Claudio R.;Leal, Cássia R.B.;Ferreira, Alda M.T.;Araújo, Flábio R.;Bonato, Ana L.V.;Kessler, Raul H.;Schenk, Maria A.M.;Soares, Cleber O.;
Pesquisa Veterinária Brasileira , 2002, DOI: 10.1590/S0100-736X2002000400005
Abstract: a molecular epidemiological study was performed with babesia bigemina isolates from five geographical regions of brazil. the genetic analysis was done with random amplification of polymorphic dna (rapd), repetitive extragenic palindromic elements-polymerase chain reaction (rep-pcr) and enterobacterial repetitive intergenic consensus sequences-polymerase chain reaction (eric-pcr) that showed genetic polymorphism between these isolates and generated fingerprinting. in rapd, ilo872 and ilo876 primers were able to detect at least one fingerprinting for each b. bigemina isolate. the amplification of b. bigemina dna fragments by rep-pcr and eric-pcr gave evidence for the presence in this haemoprotozoan of the sequences described previously in microorganisms of the bacterial kingdom. for the first time it was demonstrated that both techniques can be used for genetic analysis of a protozoan parasite, although the eric-pcr was more discriminatory than rep-pcr. the dendogram with similarity coefficient among isolates showed two clusters and one subcluster. the northeastern and mid-western isolates showed the greatest genetic diversity, while the southeastern and southern isolates were the closest. the antigenic analysis was done through indirect fluorescent antibody technique and western blotting using a panel of monoclonal antibodies directed against epitopes on the merozoite membrane surface, rhoptries and membrane of infected erythrocytes. as expected, the merozoite variable surface antigens, major surface antigen (msa)-1 and msa-2 showed antigenic diversity. however, b cell epitopes on rhoptries and infected erythrocytes were conserved among all isolates studied. in this study it was possible to identify variable and conserved antigens, which had already been described as potential immunogens. considering that an attenuated babesia clone used as immunogen selected populations capable of evading the immunity induced by this vaccine, it is necessary to evaluate more deeply
Genetic Structure of Lutzomyia longipalpis Populations in Mato Grosso Do Sul, Brazil, Based on Microsatellite Markers
Mirella F. C. Santos, Paulo E. M. Ribolla, Diego P. Alonso, José D. Andrade-Filho, Aline E. Casaril, Alda M. T. Ferreira, Carlos E. S. Fernandes, Reginaldo P. Brazil, Alessandra G. Oliveira
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0074268
Abstract: Background Lutzomyia longipalpis (Diptera: Psychodidae) is the major vector of Leishmania (Leishmania) infantum and thus plays a crucial role in the epidemiology of American visceral leishmaniasis (AVL). This vector is the best studied species of sand fly in the Neotropical region. Many studies claim that this vector is in fact a species complex; however there is still no consensus regarding the number of species that belong into this complex or the geographical distribution of sibling species. The aim of the present study was to analyze the genetic relationships within?Lu. longipalpis?populations in the state of Mato Grosso do Sul (MS), Brazil. Methodology/Principal Findings We collected 30 Lu. longipalpis (15 females and 15 males) from five localities (Campo Grande, Três Lagoas, Aquidauana, Miranda and Bonito) and 30 Lu. Cruzi from Corumbá, totaling 180 sandflies from MS, and 30 Lu. longipalpis from Estrela de Alagoas, state of Alagoas (AL), Northeast Brazil. We show that eight previously described microsatellite loci were sufficient in distinguishing Lu. longipalpis from Lu. Cruzi, which is a closely related species, and in differentiating between Lu. longipalpis collected in MS versus Estrela de Alagoas. Analyses of the genotypes revealed introgression between sympatric Lu. longipalpis and Lu. Cruzi. Conclusions/Significance Our findings support the hypothesis of cryptic species within the Lu. longipalpis complex. Furthermore, our data revealed introgression between Lu. longipalpis and Lu. cruzi. This phenomenon should be further investigated to determine the level and incidence of hybridization between these two species. We also demonstrated that microsatellite markers are a powerful tool for differentiating sand fly populations and species. The present study has elucidated the population structure of Lu. longipalpis in MS and, by extension, the Neotropical Lu. longipalpis complex itself.
Working Memory and Reading Development  [PDF]
T. L. Ferreira, C. M. T. Valentin, S. M. Ciasca
Psychology (PSYCH) , 2013, DOI: 10.4236/psych.2013.410A002
Abstract:

Purpose: To evaluate the development of working memory and reading in proficient students from 1st to 4th year of elementary school. Method: Participants were 19 people of both genders, with an average age of 8.26 years, enrolled between the 1st and 4th year of elementary school, who met the proposed inclusion criteria and were proposed and evaluated for working memory and reading level. Results: There’re no significant differences in the level of reading and working memory between genders male and female. The research points to an improved performance of working memory with the increasing age and educational level. The students belonging to the 3rd and 4th year showed better results in the physical assessment of working memory, as well as in the evaluation of the reading level. Conclusion: In this study, it was observed that with the increasing age and schooling, there was an improvement in the performance of working memory, and consequently a better performance in reading. But it cannot be inferred that only the working memory and reading complement themselves bidirectionally, because the literature indicates that other factors also help the development of reading.

Lip -dios totais e per l de cidos graxos de a€ salgadinhosa€ comercializados em Campos dos Goitacazes, RJ
Total fat and pro le of fatty acids in snacks in Campos dos Goitacazes, RJ

T. M. T. PESSANHA,K. S. FERREIRA
Alimentos e Nutri??o , 2010,
Abstract: Apesar do consumo de a€ salgadinhosa€ ter aumentado, ainda s £o escassos dados sobre sua composi § £o qu -mica. Este trabalho teve o objetivo de determinar os teores de lip -dios totais e per l de cidos graxos destes alimentos. Foram analisados 13 tipos de salgados fritos e 9 tipos de salgados assados. Os cidos graxos foram determinados por cromatogra a em fase gasosa. Os teores de lip -dios totais variaram de 2,7% a 28,9%. Os teores de cidos graxos saturados nos salgados fritos variaram entre 0,7% a 9,7% e nos assados entre 0,6% e 8,1%, com predom -nio dos cidos este rico (0,2% a 2,2%) e palm -tico (0% a 5,9%). Quanto aos insaturados cis, a faixa de varia § £o foi de 1,0% a 8,1% nos fritos e 0,5% a 12,7% nos assados, com predom -nio dos cidos essenciais linoleico (0,0% a 11,4%) e linol anico (0,0% a 1,3%). Os cidos graxos trans, foram detectados em quase todos os salgados e os teores mais elevados foram encontrados nos salgados assados, principalmente nas empadas de frango e em past is de forno de frango (0 a 5,9%).
Análise de indicadores internos e externos relevantes à resolutividade diagnóstica em laboratório de referência em imuno-histoquímica
Nonogaki, Suely;Kanamura, Cristina Takami;Oliveira, Luciana Fran?a de;Bela, M?nica Conte;Menezes, Yara de;Wakamatsu, Alda;Santos, Raimunda Telma de Macedo;Alves, Venancio Avancini Ferreira;
Jornal Brasileiro de Patologia e Medicina Laboratorial , 2007, DOI: 10.1590/S1676-24442007000400012
Abstract: objectives: the aim of this study was to evaluate the resolutivity of immunohistochemical (ihc) assays on neoplastic samples in a public health laboratory and to assess the influence of communication between the requiring institution and reference one on the quality of the ihc diagnosis. material and methods: one thousand oncological samples from eight public hospitals were submitted to ihc assay: 500 immediately before and 500 after an intervention demanding further information from the requiring pathologist. antigen retrieval was performed in a pressure cooker and the detection system was lsab plus system. the results were expressed as positive, negative or inconclusive. information about paraffin blocks, fixatives, official requiring form, the attachment of original anatomopathological report, topography of the lesion, age and gender of the patients was collected. results and conclusion: from 989 samples, 5,719 slides were stained by ihc, leading to a resolutivity for 919/989 (92.9%). the number of antigen tested ranged from one to 22 - average of 5.8 for case. panels with up to five antigens per case resolved 534 samples, whereas up to 10 markers were necessary to resolve 919 samples. even nowadays, basic information, such as anatomopathological reports, age, gender, representative and technically superior paraffin block are not always available to the reference laboratory. the improvement of such communication is essential to rationalize the flux of immunohistochemical tests and to enhance the quality of diagnostic conclusions.
Chagas' Disease and HIV Co-infection: Genotypic Characterization of the Trypanosoma cruzi Strain
Pacheco, Raquel S;Ferreira, Marcelo S;Machado, Maria Inês;Brito, Célia MM;Pires, Marize Q;Da-Cruz, Alda M;Coutinho, Sérgio G;
Memórias do Instituto Oswaldo Cruz , 1998, DOI: 10.1590/S0074-02761998000200005
Abstract: in the past few years, new aspects of the immunopathology of chagas' disease have been described in immunosuppressed patients, such as fatal central nervous system lesions related to the reactivation of the parasite. this article is the first description of the genotypic characterization, at the strain level, of trypanosoma cruzi isolated from a patient with chagas` disease/aids co-infection. the presence of four hypodense lesions was observed in the cranial compute tomographic scan. the diagnosis of aids was assessed by the detection of anti-hiv antibodies using enzyme-linked immunosorbent assay (elisa) and western blot techniques. the cd4+ lymphocyte counts were maintained under 200 cells/mm3 during one year demonstrating the severity of the state of immunosuppression. chagas' disease was confirmed by serological and parasitological methods. trypomastigote forms were visualized in a thick blood smear. the parasite isolated is genotypically similar to the cl strain. the paper reinforces that cerebral chagas' disease can be considered as another potential opportunistic infection in aids resulting from the reactivation of a dormant t. cruzi infection acquired years earlier.
Comparison between Two Ethanolic Solutions for 3’-Deoxy-3’-[18F]Fluorothymidine Elution  [PDF]
Leonardo T. C. Nascimento, Marina B. Silveira, Soraya M. Z. M. D. Ferreira, Juliana B. Silva
Advances in Chemical Engineering and Science (ACES) , 2017, DOI: 10.4236/aces.2017.71003
Abstract: 3’-Deoxy-3’-[18F]Fluorothymidine—[18F]FLT is a Positron Emission Tomography (PET) tracer which has been used for noninvasive assessment of proliferation activity in several types of cancer. During the past few years, some novel approaches for [18F]FLT synthesis have been developed, mainly focused on optimization of reaction conditions and purification methods. The present study reports the use of two different eluents in the final step of [18F]FLT production and the evaluation of its effect on radiochemical yield and product quality. The first eluent evaluated was water: ethanol (90:10, v/v), commercially available, and the second was NaCl 0.9% (saline): ethanol (92:8, v/v). The mean of the corrected radiochemical yields corresponded to 27% ± 7% for elution with water and ethanol and to 23% ± 3% for elution with saline and ethanol, which could indicate that the eluent solutions have similar elution strength. Besides, quality control results were in accordance with the requirements and demonstrated that there was no significant difference between both formulations. Considering that pharmaceutical preparations containing ethanol should be preferentially diluted with saline to avoid hemolysis, the eluent saline:ethanol (92:8, v/v) was chosen for [18F]FLT extraction and final
A Novel Synthesis Route to Produce Boron Nitride Nanotubes for Bioapplications  [PDF]
T. H. Ferreira, P. R. O. Silva, R. G. Santos, E. M. B. Sousa
Journal of Biomaterials and Nanobiotechnology (JBNB) , 2011, DOI: 10.4236/jbnb.2011.24052
Abstract: Nanostructures of boron nitride have attracted a great deal of interest due to their potential applications that comprise a broad range of topics, including biomedical technology, since it presents good chemical stability and suggests good biological inertia. This paper reports a facile and effective synthesis based on CVD process with new conditions to produce boron nitride nanotubes in higher amount using boron powder, ammonium nitrate and hematite as catalysts in tubular furnace, without using extreme conditions. The characterization of the material was carried out by Fourier transformed infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). From the results, it was possible to verify the production of a hexagonal BN nanotube filled with Fe nanoparticles. It was possible to understand the reactions involved in synthesis process, and also confirm the formation of hexagonal boron nitride nanotubes with iron nanoparticles as catalysts. Depending on the final use, samples need to be purified to analyze their unique properties in some bioapplications. In the other hand, sometimes BNNTs containing Fe nanoparticles have potential for use in therapeutic drug, gene and radionuclide delivery, and radio frequency methods for the catabolism of tumors via hyperthermia. In this sense, some application-related studies on BNNTs such as biocompatibility tests have also been investigated in both pure and BN nanotube filled with Fe.
Printable Optical Filters for Visible Optical Communications  [PDF]
P. S. André, L. Nero, Vania T. Freitas, M. S. Relvas, R. A. S. Ferreira
Optics and Photonics Journal (OPJ) , 2013, DOI: 10.4236/opj.2013.32B033
Abstract:

The design, production and characterization of tailored printable optical filters for visible optical communications are demonstrated. As result, the average color difference between the specified and the produced filters is 32.6, quantified in terms of CIELAB coordinates.

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