Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 21
Filtrar
Mais filtros











Intervalo de ano de publicação
1.
Front Bioeng Biotechnol ; 11: 1202126, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37485316

RESUMO

The outbreak of COVID-19, a disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, is regarded as the most severe of the documented coronavirus pandemics. The measurement and monitoring of SARS-CoV-2 antibody levels by serological tests are relevant for a better epidemiological and clinical understanding of COVID-19. The aim of this work was to design a method called the SARS-CoV-2 antibody detection method (SARS-CoV-2 AbDM) for fluorescence immunodetection of anti-SARS-CoV-2 IgG and IgM on both plate and microfluidic chip. For this purpose, a system with magnetic beads that immobilize the antigen (S protein and RBD) on its surface was used to determine the presence and quantity of antibodies in a sample in a single reaction. The SARS-CoV-2 AbDM led to several advantages in the performance of the tests, such as reduced cost, possibility of performing isolated or multiple samples, potential of multiplex detection, and capacity to detect whole blood samples without losing resolution. In addition, due to the microfluidic chip in conjunction with the motorized actuated platform, the time, sample quantity, and operator intervention during the process were reduced. All these advantages suggest that the SARS-CoV-2 AbDM has the potential to be developed as a PoC that can be used as a tool for seroprevalence monitoring, allowing a better understanding of the epidemiological and clinical characteristics of COVID-19 and contributing to more effective and ethical decision-making in strategies to fight against the COVID-19 pandemic.

2.
Int J Infect Dis ; 108: 20-26, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33945867

RESUMO

OBJECTIVES: A retrospective study was conducted to identify the prevalence of COVID-19 through serology and RT-PCR in children, adolescents and adults. A database of the COVID-19 Tracking Program in school children was used. METHODS: The data comprised sociodemographic and clinical variables, results of serological tests (IgM and IgG), and real-time-polymerase chain reaction (RT-PCR) results of IgM-positive individuals. The statistical analysis was performed with a 5% significance level. RESULTS: Among 423 children, 107 (25.3%) exhibited seroprevalence with IgG, IgM or IgG/IgM; among 854 adolescents, 250 (29.2%) had positive serology; and among 282 adults, 59 (20.9%) were positive. The frequency of positivity on RT-PCR for SARS-CoV-2 was 3.5%, 3.6% and 6.0% in children, adolescents and adults, respectively. Children had a lower incidence of symptoms than adolescents (p = 0.001) and adults (p = 0.003); the most frequent were fever, ageusia, anosmia, headache, dry cough, sore throat, muscle pain, runny nose, dyspnoea, and diarrhoea. CONCLUSIONS: The prevalence rate for all groups was 26.7% in serology and 4.04% in RT-PCR. Children had lower rates of IgM and fewer symptoms compared with adolescents and adults. The data suggest the potential for transmissibility in all age groups.


Assuntos
COVID-19 , Adolescente , Adulto , Brasil/epidemiologia , Criança , Humanos , Prevalência , Estudos Retrospectivos , SARS-CoV-2 , Estudos Soroepidemiológicos
3.
J Neurosci Methods ; 358: 109194, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33901567

RESUMO

BACKGROUND: Dot blot technique has been used in a similar way to western blotting, with the major difference being the lack of protein separation with electrophoresis. Protein samples are spotted over a membrane paper, the identification and quantification of a protein is achieved by immunodetection procedures such as colorimetry, fluorescence or chemiluminescence. This technique is widely accepted, but it uses large amounts of sample and antibodies to reveal the presence of the target protein. Significant milestones have been reached to achieve better results with the use of less sample and reagents; however, the ninety-six-well format is still in use. NEW METHOD: In this work, we propose an innovation to this technique, reducing the amount of sample and antibodies to identify a specific protein when compared to the regular dot blot method. Procedure consists of using a sample volume of approximately 200 nanoliters deposited with a multineedle device developed by our group. RESULTS: Five samples of standard protein or antigen can be spotted in a Cartesian format to identify and quantify the protein involved in physiological or pathological conditions. In addition, at least five replicates of sample or antigen are used to enable better statistics to calculate the concentration of every standard and the protein present in a sample. CONCLUSIONS: Hundreds of samples can be deposited in a few minutes and analyzed in a single experimental session. To validate this method, which we called nano dot blot, six proteins involved in the inflammation process were tested in acute and chronic rat models of seizures.


Assuntos
Anticorpos , Proteínas , Animais , Western Blotting , Eletroforese , Immunoblotting , Ratos
4.
Braz. j. vet. pathol ; 13(1): 17-20, Mar. 2020. ilus
Artigo em Inglês | VETINDEX | ID: biblio-1469748

RESUMO

Melanoma is a neoplasm originating from melanocytes and represents 7% of skin tumors and the most common in oral cavity of dogs. Melanoma may present melanocytic pigment in its cytoplasm in varying quantity and its characterization by immunohistochemistry (IHC) is challenging due to the use of chromogen diaminobenzidine (DAB) which itself produces a brown product what makes difficult to distinguish from melanin pigment in this technique. To demonstrate a reliable technique, the use of the Giemsa counterstaining was performed in the IHC of melanomas with different degrees of pigmentation for different cytoplasmic, membrane and nuclear markers. The modification in the IHC technique by the counterstaining of Giemsa allows observable differences under the microscope between melanic pigment(in a blue-green stain), while the DAB chromogen will be observed in brown. With this technique, the prognostic and predictive interpretation of markers in canine melanomas may be more reliable in definitions of clinical behaviors and inexperimental analyzes.


Assuntos
Animais , Cães , Melanoma/diagnóstico , Melanoma/veterinária , Corantes Azur
5.
Braz. J. Vet. Pathol. ; 13(1): 17-20, Mar. 2020. ilus
Artigo em Inglês | VETINDEX | ID: vti-28874

RESUMO

Melanoma is a neoplasm originating from melanocytes and represents 7% of skin tumors and the most common in oral cavity of dogs. Melanoma may present melanocytic pigment in its cytoplasm in varying quantity and its characterization by immunohistochemistry (IHC) is challenging due to the use of chromogen diaminobenzidine (DAB) which itself produces a brown product what makes difficult to distinguish from melanin pigment in this technique. To demonstrate a reliable technique, the use of the Giemsa counterstaining was performed in the IHC of melanomas with different degrees of pigmentation for different cytoplasmic, membrane and nuclear markers. The modification in the IHC technique by the counterstaining of Giemsa allows observable differences under the microscope between melanic pigment(in a blue-green stain), while the DAB chromogen will be observed in brown. With this technique, the prognostic and predictive interpretation of markers in canine melanomas may be more reliable in definitions of clinical behaviors and inexperimental analyzes.(AU)


Assuntos
Animais , Cães , Melanoma/diagnóstico , Melanoma/veterinária , Corantes Azur
6.
Toxicon ; 167: 168-171, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31207353

RESUMO

In the last decades, main advances were achieved in the identification, structural and pharmacological characterization of Phoneutria nigriventer toxins. However, studies on the venom-producing apparatus are rare. Presently, we applied immunolabeling to historesin-embedded cross-sections of P. nigriventer venom glands. Toxins and toxin-secreting cells were successfully located in situ, using laser confocal scanning microscopy. The methodological strategy was successful and may be applied in future studies on venom glands and other secreting tissues, in general.


Assuntos
Venenos de Aranha/análise , Aranhas/química , Animais , Imunofluorescência , Metacrilatos , Microscopia Confocal/métodos
7.
Acta sci. vet. (Impr.) ; 46: 1-8, 2018. ilus, graf
Artigo em Inglês | VETINDEX | ID: biblio-1457820

RESUMO

Background: The immunoglobulin Y is a principal antibody current in the blood of hens, which are transferred from the maternal blood serum to the egg yolk. The extraction of IgY from the egg yolk apply animal welfare when compared to the extraction of IgG, reducing the number of animals and prevent a bleeding of hens through the extraction of the IgY from eggs, besides that IgY presenting high specificity for antigenic binding. The objective of this study was to produce specific polyclonal IgY antibodies anti-Brucella abortus by immunizing hens with B19 vaccine and evaluate their reactivity through Buffered Acidified Plate Antigen (BAPA), 2-Mercaptoethanol (2-ME) and indirect ELISA diagnostic tests.Materials, Methods & Results: Four 25-week-old White Leghorn hens were immunized, two of them comprising the control group (Group 1) with phosphate-buffered saline (PBS) with adjuvant, and the others two immunized with B19 vaccine (Brucella abortus vaccine strain B19), representing the Group 2. The immunizations occurred six times with a 15-day interval between each. Blood samples were taken biweekly (seven times); and daily, the eggs were collected for 13 weeks, the first collection of blood and eggs, performed one week before the first immunization of each group. The IgY was purified from egg yolk, using the method of dilution in acid water and precipitation with ammonium sulfate for delipidation. BAPA, 2-ME and ELISA tests performed to verify the specificity of IgY confirmed the reactivity of polyclonal antibodies specific to the antigen used both in blood serum samples and in the purified egg yolks. The hens from the control group did not present reactivity in the diagnostic tests used, which was already expected, since no antigen was used in any of their immunizations. Hens immunized with the Brucella abortus B19 vaccine produced detectable reactive antibodies in the three tests used on blood serum and IgY samples extracted from the egg yolk.[...]


Assuntos
Feminino , Animais , Brucella abortus/imunologia , Formação de Anticorpos , Galinhas/imunologia , Imunoglobulinas/análise , Ovos/análise , Ensaio de Imunoadsorção Enzimática/veterinária , Mercaptoetanol
8.
Acta sci. vet. (Online) ; 46: 1-8, 2018. ilus, graf
Artigo em Inglês | VETINDEX | ID: vti-15917

RESUMO

Background: The immunoglobulin Y is a principal antibody current in the blood of hens, which are transferred from the maternal blood serum to the egg yolk. The extraction of IgY from the egg yolk apply animal welfare when compared to the extraction of IgG, reducing the number of animals and prevent a bleeding of hens through the extraction of the IgY from eggs, besides that IgY presenting high specificity for antigenic binding. The objective of this study was to produce specific polyclonal IgY antibodies anti-Brucella abortus by immunizing hens with B19 vaccine and evaluate their reactivity through Buffered Acidified Plate Antigen (BAPA), 2-Mercaptoethanol (2-ME) and indirect ELISA diagnostic tests.Materials, Methods & Results: Four 25-week-old White Leghorn hens were immunized, two of them comprising the control group (Group 1) with phosphate-buffered saline (PBS) with adjuvant, and the others two immunized with B19 vaccine (Brucella abortus vaccine strain B19), representing the Group 2. The immunizations occurred six times with a 15-day interval between each. Blood samples were taken biweekly (seven times); and daily, the eggs were collected for 13 weeks, the first collection of blood and eggs, performed one week before the first immunization of each group. The IgY was purified from egg yolk, using the method of dilution in acid water and precipitation with ammonium sulfate for delipidation. BAPA, 2-ME and ELISA tests performed to verify the specificity of IgY confirmed the reactivity of polyclonal antibodies specific to the antigen used both in blood serum samples and in the purified egg yolks. The hens from the control group did not present reactivity in the diagnostic tests used, which was already expected, since no antigen was used in any of their immunizations. Hens immunized with the Brucella abortus B19 vaccine produced detectable reactive antibodies in the three tests used on blood serum and IgY samples extracted from the egg yolk.[...](AU)


Assuntos
Animais , Feminino , Galinhas/imunologia , Imunoglobulinas/análise , Brucella abortus/imunologia , Ovos/análise , Formação de Anticorpos , Ensaio de Imunoadsorção Enzimática/veterinária , Mercaptoetanol
9.
Front Immunol ; 8: 977, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28871254

RESUMO

With just three CDRs in their variable domains, the antigen-binding site of camelid heavy-chain-only antibodies (HcAbs) has a more limited structural diversity than that of conventional antibodies. Even so, this does not seem to limit their specificity and high affinity as HcAbs against a broad range of structurally diverse antigens have been reported. The recombinant form of their variable domain [nanobody (Nb)] has outstanding properties that make Nbs, not just an alternative option to conventional antibodies, but in many cases, these properties allow them to reach analytical or diagnostic performances that cannot be accomplished with conventional antibodies. These attributes include comprehensive representation of the immune specificity in display libraries, easy adaptation to high-throughput screening, exceptional stability, minimal size, and versatility as affinity building block. Here, we critically reviewed each of these properties and highlight their relevance with regard to recent developments in different fields of immunosensing applications.

10.
Molecules ; 22(3)2017 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-28272377

RESUMO

The behavior of lyotropic biomimetic systems in drug delivery was reviewed. These behaviors are influenced by drug properties, the initial water content, type of lyotropic liquid crystals (LLC), swell ability, drug loading rate, the presence of ions with higher or less kosmotropic or chaotropic force, and the electrostatic interaction between the drug and the lipid bilayers. The in vivo interaction between LCC-drugs, and the impact on the bioavailability of drugs, was reviewed. The LLC with a different architecture can be formed by the self-assembly of lipids in aqueous medium, and can be tuned by the structures and physical properties of the emulsion. These LLC lamellar phase, cubic phase, and hexagonal phase, possess fascinating viscoelastic properties, which make them useful as a dispersion technology, and a highly ordered, thermodynamically stable internal nanostructure, thereby offering the potential as a sustained drug release matrix for drug delivery. In addition, the biodegradable and biocompatible nature of lipids demonstrates a minimum toxicity and thus, they are used for various routes of administration. This review is not intended to provide a comprehensive overview, but focuses on the advantages over non modified conventional materials and LLC biomimetic properties.


Assuntos
Biomimética , Cristais Líquidos/química , Biomimética/métodos , Técnicas Biossensoriais , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Elasticidade , Emulsões , Permeabilidade , Viscosidade
11.
Comp Cytogenet ; 10(2): 255-68, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27551347

RESUMO

Characidium gomesi Travasso, 1956 specimens from the Pardo River have up to four heterochromatic supernumerary chromosomes, derived from the sex chromosomes. To access the meiotic behavior and distribution of an active chromatin marker, males and females of Characidium gomesi with two or three B chromosomes were analyzed. Mitotic chromosomes were characterized using C-banding and FISH with B chromosome probes. Meiocytes were subjected to immunofluorescence-FISH assay using anti-SYCP3, anti-H3K4m, and B chromosomes probes. Molecular homology of supernumeraries was confirmed by FISH and by its bivalent conformation in individuals with two of these chromosomes. In individuals with three Bs, these elements formed a bivalent and a univalent. Supernumerary and sex chromosomes exhibited H3K4m signals during pachytene contrasting with their heterochromatic and asynaptic nature, which suggest a more structural role than functional of this histone modification. The implications of this result are discussed in light of the homology, meiotic nuclear organization, and meiotic silencing of unsynapsed chomatin.

12.
Rev. cuba. med. trop ; 62(3): 167-179, sep.-dic. 2010.
Artigo em Espanhol | LILACS | ID: lil-584949

RESUMO

Se hizo una valoración del impacto de los ensayos inmunoenzimáticos en la analítica de base inmunoquímica en las últimas 4 décadas, en la detección de agentes infecciosos o los productos asociado a su presencia y(o) actividad patogénica. Además se hace una incursión en algunos diseños y formatos que han tenido estos inmunoensayos desde los métodos electroquímicos de detección, los ensayos para detectar actividad proteolítica de origen microbiano y sus inhibidores como posibles blancos terapéuticos, los inmunoensayos directos de triple anticuerpo para lograr mayor sensibilidad, reveladores alternativos de la actividad enzimática, ensayos para el estudio de la serología viral con un mínimo de determinaciones, así como ensayos de competencia para evaluar la efectividad de candidatos vacunales basados en combinaciones peptídicas seleccionadas. Se concluyó con una rápida visión del futuro inmediato de este tipo de inmunoensayos a la luz de las tecnologías analíticas emergentes de detección.


This paper assessed the impact of the immunoenzymatic assays on the field of the immunochemistry-based analytics for the last 40 years, and on the detection of infectious agents or the products related to their presence and/or pathogenic activity. It also addressed some designs and formats of these immunoassays from electrochemical methods of detection, assays to determine proteolytic microbial activity and their inhibitors as possible therapeutical targets, more sensitive direct triple antibody systems, alternative enzymatic activity detectors, assays for viral serology of minimal determinations to competitive assays for evaluation of vaccinal candidate effectiveness based on selected peptide combinations. Finally, it provided a rapid overview of the near future of this type of immunoassays in the light of the emerging detection analytical technologies.


Assuntos
Humanos , Técnicas Imunoenzimáticas/métodos , Infecções/microbiologia
13.
Rev. cuba. med. trop ; 62(2): 85-92, Mayo-ago. 2010.
Artigo em Espanhol | LILACS | ID: lil-584944

RESUMO

En este trabajo se presentó la historia y evolución, desde el descubrimiento, de los anticuerpos, así como la elucidación de su compleja estructura y función que ha servido de base metodológica para crear paradigmas inimaginables en su momento, como la fina especificidad de reconocimiento; también derrumbar otros, aparentemente inamovibles, como la invariabilidad y universalidad del genoma celular. Se revisó la evolución de los sistemas analíticos basados en la reacción antígeno-anticuerpos para llegar al estado actual y problemática de las enfermedades infecciosas y el determinante papel que desempeñan en su control la detección y el monitoreo de agentes infecciosos. La extraordinaria capacidad de los anticuerpos para discriminar estructuras antigénicamente similares, les permite ser parte fundamental de los inmunoensayos como herramientas básicas de lo que es hoy día una disciplina productiva muy bien establecida: la inmunotecnología.


This paper presented the history and evolution of the antibodies since their discovery. It also elucidated their complex structure and function that have served at a given time as methodological basis for creating unimaginable paradigms such as fine recognition specificity, and also for destroying other apparently immutable ones as invariability and universality of the cellular genome. A review was made of the evolution of antigen-antibody reaction-based analytical systems up to the present, the situation of infectious diseases and the determining role that detection and monitoring of infectious agents play in their control. The extraordinary capability of antibodies to discriminate antigenically similar structures allows them to be fundamental tools in immunoassays and also in a well-established discipline at present, that is, immunotechnology.


Assuntos
Humanos , Anticorpos/análise , Infecções/imunologia , Infecções/microbiologia , Técnicas Imunoenzimáticas
14.
J. appl. microbiol ; 109(1): 35-43, Nov 14, 2009.
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP, SESSP-IBACERVO | ID: biblio-1063795

RESUMO

The aim of study was to develop a colony immunoblot assay to differentiatetypical from atypical enteropathogenic Escherichia coli (EPEC) by detectionof bundle-forming pilus (BFP) expression. Anti-BFP antiserum was raised in rabbits and itsreactivity was confirmed by immunoelectron microscopy and by immunoblotting recognizing bundlin, the major pilus repeating subunit. The bacterial isolates tested in the colony immunoblot assay were grown in different media. Proteins from bacterial isolates were transferred to nitrocellulose membrane after treatment with phosphate buffer containing Triton X-100, EDTA and sodium chloride salts. When 24 typical EPEC and 96 isolates including, 72 atypical EPEC, 13 Gram-negative type IV-expressing strains and 11 enterobacteriaceae were cultivated in Dulbecco’s Modified Eagle’s Medium agar containing fetal bovine serum or in blood agar in the presence of CaCl2, they showed a positivity of 92 and 83%, and specificity of 96 and 97%, respectively. The assay enables reliable identification of BFP-expressing isolatesand contributes to the differentiation of typical and atypical EPEC.The colony immunoblot for BFP detectiondeveloped in this study combines the simplicity of an immunoserologicalassay with the high efficiency of testing a large number of EPECcolonies.


Assuntos
Humanos , Escherichia coli Enteropatogênica , Escherichia coli Enteropatogênica/genética , Immunoblotting/métodos , Polietilenoglicóis/análise
15.
Rev. bras. mastologia ; 19(3): 94-100, jul.-set. 2009. ilus
Artigo em Português | LILACS | ID: lil-558638

RESUMO

O antígeno Ki-67 é utilizado para avaliar a atividade proliferativa em vários tumores. No entanto, o papel do Ki-67 como fator prognóstico em câncer de mama é ainda indefinido. O objetivo do trabalho foi analisar a expressão do antígeno Ki-67 correlacionando com fatores clínico-patológicos e sobrevida em pacientes com câncer de mama. Realizou-se a análise imunoistoquímica utilizando anticorpos monoclonais MIB-1 em 140 amostras de câncer de mama de mulheres com idade entre 27 e 90 anos, atendidas no Hospital Araújo Jorge da Associação de Combate ao Câncer de Goiás. O ponto de corte para a análise foi de 25%. A sobrevida global em cinco anos foi de 77,1%. Houve sobrevida significativamente pior nos casos com linfonodos positivos (p < 0,0001), tumores maiores (p < 0,0001), estádios mais avançados (p < 0,0001) e pacientes com receptores hormonais negativos (p = 0,019). Pacientes com imunodetecção de Ki-67 em mais de 25% das células tiveram pior sobrevida quando comparadas àquelas que expressaram Ki-67 em menos de 25% das células examinadas (70,8% x 82,7%), porém essa diferença não foi estatisticamente significativa (p = 0,094). A hiperexpressão do Ki-67 não se correlacionou com pior sobrevida no grupo de pacientes analisadas.


The Ki-67 antigen is used to evaluate proliferative activity in several tumors. However the role of the Ki-67 as a prognostic factor in breast cancer is still undefined. The aim of present study was to analyze the expression of Ki-67 antigen correlating with clinicopathological factors and survival in patients with breast cancer. We carried out an immunohistochemical analysis using MIB-1 monoclonal antibody in 140 specimen of breast cancer of women with age between 27 and 90 years. The cut-off point was 25%. The five year overall survival was 77.1%. There was a significant worse survival of patients with node positive (p < 0.0001), larger tumors (p < 0.0001), more advanced stages (p < 0.0001) and with negative hormonal receptors (p = 0.019). Patients with Ki-67 immunodetection in more than 25% of the tumors cells showed a poorer outcome when compared with those that express Ki-67 in less than 25% of the cells examined (70.8% x 82.7%), however this difference was not statistically significative (p = 0,094). The overexpression of Ki-67 did not correlate with a worse survival in the group of patients analyzed.


Assuntos
Humanos , Masculino , Feminino , /biossíntese , /metabolismo , Imuno-Histoquímica , Neoplasias da Mama/diagnóstico , Distribuição de Qui-Quadrado , Prognóstico , Estudos Retrospectivos , Análise de Sobrevida
16.
Semina ciênc. agrar ; 27(4): 617-628, out.-dez. 2006. ilus
Artigo em Português | LILACS | ID: lil-464864

RESUMO

O monitoramento constante da contaminação fúngica é imprescindível para assegurar a qualidade e segurança dos alimentos, reduzindo as perdas econômicas, assim como os riscos à saúde humana e animal. Os métodos tradicionais de identificação e detecção de fungos (cultivo em diversos meios, exame microscópico e análises bioquímicas) geralmente consomem muito tempo e exigem pessoal com experiência. Os imunoensaios, particularmente os ensaios imunoenzimáticos, constituem uma alternativa promissora aos métodos tradicionais devido à alta sensibilidade, especificidade, reprodutibilidade e potencial como método rápido de controle de qualidade. Dentre os ensaios imunoenzimáticos, aqueles baseados em exoantígenos são os mais empregados na resolução de problemas taxonômicos, detecção e identificação de fungos toxigênicos. Nesta revisão serão abordados conceitos básicos de imunoensaios, métodos de detecção de fungos, assim como diversos ensaios imunoenzimáticos para a detecção de fungos toxigênicos em alimentos.


Constant monitoring of mould contamination is essential in order to assure the food quality and safetyand reduce the economic losses, as well as to minimize the potential hazards to human and animal health.The traditional methods for mould identification and detection (culture in several media, microscopicexamination and chemical analysis) are usually time-consuming and require trained staff. Immunoassays,particularly enzyme-linked immunosorbent assay (ELISA) could be a promising alternative to the traditionalmethods due to high sensitivity, specificity, reproducibility and potential for use in rapid quality control.Among ELISAs, those based on exoantigens are the most employed in the resolution of taxonomicproblems, detection and identification of toxigenic fungi. This review discusses the basic principles ofimmunoassays, methods of mould detection and the several ELISAs developed for toxigenic fungidetection in food


Assuntos
Fungos , Imunoensaio
17.
Semina ciênc. agrar ; 27(1): 71-80, jan.-mar. 2006. ilus, tab
Artigo em Português | LILACS | ID: lil-453111

RESUMO

Fusarium verticillioides Sacc. Niremberg (=F. moniliforme Sheldon) é um patógeno primário de milho e principal produtor de fumonisinas. Este fungo pode causar perdas econômicas significativas para produtores e processadores de grãos, criadores de animais, além de representar sérios riscos á saúde humana e animal. Diversos métodos para a detecção de fungos têm sido utilizados, porém a maioria demanda tempo e pessoal treinado. Por outro lado, os métodos imunológicos, particularmente os ensaios imunoenzimáticos, apresentam diversas vantagens para o emprego rápido em controle de qualidade. Neste trabalho, foram obtidos exoantígenos de 8 isolados de F. verticillioides para a produção de anticorpos policlonais. O perfil eletroforético dos antígenos apresentou bandas com massas moleculares aparentes variando entre 17 e 170 kDa. Os antígenos de 3 isolados (97K, 113F e 162A), tendo como base a concentração de proteínas e número de bandas, foram escolhidos para a produção de anticorpos policlonais. O soro imune anti-97K, com maior título no ELISA indireto (1:12.800), apresenta potencial para a imunodetecção de Fusarium verticillioides.


Fusarium verticillioides Sacc. Niremberg (=F. moniliforme Sheldon) is a primary corn pathogen and themain fumonisin producer. This fungus can cause significant economical losses for the farmers, grainprocessors, animal producers and risk for human and animal health. Several methods for mould detectionhave been used, however most of these are time-consuming and require trained staff. Otherwise,immunoassays (particularly enzyme-linked immunosorbent assay, or ELISA) provide several advantagesand potential for use in rapid quality control. In this work exoantigens from eight F. verticillioidesisolates were obtained for further production of polyclonal antibodies. The electrophoretic profile ofthese antigens showed protein bands with molecular mass ranging from 17 to 170 kDa. The antigens from3 isolates (97K, 113F and 162A) were selected for polyclonal antibodies production, based on proteinconcentration and number of bands. Antiserum against F. verticillioides 97K exoantigens, which showed thehighest titre in indirect ELISA (1:12.800), has potential for the immunodetection of F. verticillioides


Assuntos
Fumonisinas , Fungos , Fusarium , Micotoxinas
18.
Semina Ci. agr. ; 27(4): 613-628, 2006.
Artigo em Português | VETINDEX | ID: vti-763094

RESUMO

Constant monitoring of mould contamination is essential in order to assure the food quality and safety and reduce the economic losses, as well as to minimize the potential hazards to human and animal health. The traditional methods for mould identification and detection (culture in several media, microscopic examination and chemical analysis) are usually time-consuming and require trained staff. Immunoassays, particularly enzyme-linked immunosorbent assay (ELISA) could be a promising alternative to the traditional methods due to high sensitivity, specificity, reproducibility and potential for use in rapid quality control. Among ELISAs, those based on exoantigens are the most employed in the resolution of taxonomic problems, detection and identification of toxigenic fungi. This review discusses the basic principles of immunoassays, methods of mould detection and the several ELISAs developed for toxigenic fungi detection in food.


O monitoramento constante da contaminação fúngica é imprescindível para assegurar a qualidade e segurança dos alimentos, reduzindo as perdas econômicas, assim como os riscos à saúde humana e animal. Os métodos tradicionais de identificação e detecção de fungos (cultivo em diversos meios, exame microscópico e análises bioquímicas) geralmente consomem muito tempo e exigem pessoal com experiência. Os imunoensaios, particularmente os ensaios imunoenzimáticos, constituem uma alternativa promissora aos métodos tradicionais devido à alta sensibilidade, especificidade, reprodutibilidade e potencial como método rápido de controle de qualidade. Dentre os ensaios imunoenzimáticos, aqueles baseados em exoantígenos são os mais empregados na resolução de problemas taxonômicos, detecção e identificação de fungos toxigênicos. Nesta revisão serão abordados conceitos básicos de imunoensaios, métodos de detecção de fungos, assim como diversos ensaios imunoenzimáticos para a detecção de fungos toxigênicos em alimentos.

19.
Semina ciênc. agrar ; 27(4): 613-628, 2006.
Artigo em Português | LILACS-Express | VETINDEX | ID: biblio-1433215

RESUMO

Constant monitoring of mould contamination is essential in order to assure the food quality and safety and reduce the economic losses, as well as to minimize the potential hazards to human and animal health. The traditional methods for mould identification and detection (culture in several media, microscopic examination and chemical analysis) are usually time-consuming and require trained staff. Immunoassays, particularly enzyme-linked immunosorbent assay (ELISA) could be a promising alternative to the traditional methods due to high sensitivity, specificity, reproducibility and potential for use in rapid quality control. Among ELISAs, those based on exoantigens are the most employed in the resolution of taxonomic problems, detection and identification of toxigenic fungi. This review discusses the basic principles of immunoassays, methods of mould detection and the several ELISAs developed for toxigenic fungi detection in food.


O monitoramento constante da contaminação fúngica é imprescindível para assegurar a qualidade e segurança dos alimentos, reduzindo as perdas econômicas, assim como os riscos à saúde humana e animal. Os métodos tradicionais de identificação e detecção de fungos (cultivo em diversos meios, exame microscópico e análises bioquímicas) geralmente consomem muito tempo e exigem pessoal com experiência. Os imunoensaios, particularmente os ensaios imunoenzimáticos, constituem uma alternativa promissora aos métodos tradicionais devido à alta sensibilidade, especificidade, reprodutibilidade e potencial como método rápido de controle de qualidade. Dentre os ensaios imunoenzimáticos, aqueles baseados em exoantígenos são os mais empregados na resolução de problemas taxonômicos, detecção e identificação de fungos toxigênicos. Nesta revisão serão abordados conceitos básicos de imunoensaios, métodos de detecção de fungos, assim como diversos ensaios imunoenzimáticos para a detecção de fungos toxigênicos em alimentos.

20.
Semina Ci. agr. ; 27(4): 613-628, 2006.
Artigo em Português | VETINDEX | ID: vti-472660

RESUMO

Constant monitoring of mould contamination is essential in order to assure the food quality and safety and reduce the economic losses, as well as to minimize the potential hazards to human and animal health. The traditional methods for mould identification and detection (culture in several media, microscopic examination and chemical analysis) are usually time-consuming and require trained staff. Immunoassays, particularly enzyme-linked immunosorbent assay (ELISA) could be a promising alternative to the traditional methods due to high sensitivity, specificity, reproducibility and potential for use in rapid quality control. Among ELISAs, those based on exoantigens are the most employed in the resolution of taxonomic problems, detection and identification of toxigenic fungi. This review discusses the basic principles of immunoassays, methods of mould detection and the several ELISAs developed for toxigenic fungi detection in food.


O monitoramento constante da contaminação fúngica é imprescindível para assegurar a qualidade e segurança dos alimentos, reduzindo as perdas econômicas, assim como os riscos à saúde humana e animal. Os métodos tradicionais de identificação e detecção de fungos (cultivo em diversos meios, exame microscópico e análises bioquímicas) geralmente consomem muito tempo e exigem pessoal com experiência. Os imunoensaios, particularmente os ensaios imunoenzimáticos, constituem uma alternativa promissora aos métodos tradicionais devido à alta sensibilidade, especificidade, reprodutibilidade e potencial como método rápido de controle de qualidade. Dentre os ensaios imunoenzimáticos, aqueles baseados em exoantígenos são os mais empregados na resolução de problemas taxonômicos, detecção e identificação de fungos toxigênicos. Nesta revisão serão abordados conceitos básicos de imunoensaios, métodos de detecção de fungos, assim como diversos ensaios imunoenzimáticos para a detecção de fungos toxigênicos em alimentos.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA