ABSTRACT
BACKGROUND The high demand for adequate material for the gold standard reverse transcription real-time polymerase chain reaction (RT-qPCR)-based diagnosis imposed by the Coronavirus disease 2019 (COVID-19) pandemic, combined with the inherent contamination risks for healthcare workers during nasopharyngeal swab (NP) sample collection and the discomfort it causes patients, brought the need to identify alternative specimens suitable for the diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). OBJECTIVES The aim of this work was to compare saliva and gingival fluid swabs to NP swabs as specimens for RT-qPCR-based SARS-CoV-2 diagnosis. METHODS We compared gingival fluid swabs (n = 158) and saliva (n = 207) to the rayon-tipped NP swabs obtained from mild-symptomatic and asymptomatic subjects as specimens for RT-qPCR for SARS-CoV-2 detection. FINDINGS When compared to NP swabs, gingival fluid swabs had a concordance rate of 15.4% among positive samples, zero among inconclusive, and 100% among negative ones. For saliva samples, the concordance rate was 67.6% among positive samples, 42.9% among inconclusive, and 96.8% among negative ones. However, the concordance rate between saliva and NP swabs was higher (96.9%) within samples with lower cycle threshold (Ct) values (Ct > 10 ≤ 25). MAIN CONCLUSIONS Our data suggests that whereas gingival fluid swabs are not substitutes for NP swabs, saliva might be considered whenever NP swabs are not available or recommended.
Subject(s)
Humans , COVID-19 Testing , COVID-19 , Saliva , Specimen Handling , Nasopharynx , Real-Time Polymerase Chain Reaction , SARS-CoV-2Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Young Adult , Asthma/physiopathology , Respiratory Tract Infections/virology , Cohort Studies , Disease Progression , Respiratory Tract Infections/complications , Respiratory Tract Infections/physiopathology , Severity of Illness IndexABSTRACT
Aims: To determine the frequency of viral pathogens causing upper respiratory tract infections in non-hospitalized, symptomatic adults in the city of Rio de Janeiro. Methods: Respiratory samples (nasal/throat swabs) were collected between August 2010 and November 2012 and real time PCR was used to detect different viral pathogens. Results: Viruses were detected in 32.1% (43/134) of samples from 101 patients. Specifically, 9% (12/134) were positive for HBoV, 8.2% (11/134) were positive for HAdV, 5.2% (7/134) were positive for HRV, and 1.5% (2/134) were positive for FLUBV or HMPV, as single infections. HRSV-A, HPIV-3, and HCoV-HKU1 were detected in one (0.75%) sample each. Co-infections were detected in 4.8% (6/134) of the samples. Peaks of viral infections were observed in March, April, May, August, and October. However, positive samples were detected all year round. Only 23.3% (10/43) of the positive samples were collected from patients with febrile illness. Conclusion: Results presented in this report suggest that respiratory viral infections are largely under diagnosed in immunocompetent adults. Although the majority of young adult infections are not life-threatening they may impose a significant burden, especially in developing countries since these individuals represent a large fraction of the working force. .
Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Young Adult , Respiratory Tract Infections/virology , Age Distribution , Brazil/epidemiology , Real-Time Polymerase Chain Reaction , Respiratory Tract Infections/epidemiology , SeasonsABSTRACT
Asymptomatic influenza virus infections in pigs are frequent and the lack of measures for controlling viral spread facilitates the circulation of different virus strains between pigs. The goal of this study was to demonstrate the circulation of influenza A virus strains among asymptomatic piglets in an abattoir in Brazil and discuss the potential public health impacts. Tracheal samples (n = 330) were collected from asymptomatic animals by a veterinarian that also performed visual lung tissue examinations. No slaughtered animals presented with any noticeable macroscopic signs of influenza infection following examination of lung tissues. Samples were then analysed by reverse transcription-polymerase chain reaction that resulted in the identification of 30 (9%) influenza A positive samples. The presence of asymptomatic pig infections suggested that these animals could facilitate virus dissemination and act as a source of infection for the herd, thereby enabling the emergence of influenza outbreaks associated with significant economic losses. Furthermore, the continuous exposure of the farm and abattoir workers to the virus increases the risk for interspecies transmission. Monitoring measures of swine influenza virus infections and vaccination and monitoring of employees for influenza infection should also be considered. In addition regulatory agencies should consider the public health ramifications regarding the potential zoonotic viral transmission between humans and pigs.
Subject(s)
Animals , Male , Influenza A virus/isolation & purification , Occupational Exposure , Orthomyxoviridae Infections/veterinary , Swine Diseases/virology , Abattoirs , Asymptomatic Diseases/epidemiology , Brazil/epidemiology , Influenza A virus/genetics , Orthomyxoviridae Infections/diagnosis , Orthomyxoviridae Infections/epidemiology , Orthomyxoviridae Infections/transmission , Reverse Transcriptase Polymerase Chain Reaction , Risk Factors , Sus scrofa , Swine , Swine Diseases/diagnosis , Swine Diseases/epidemiology , Swine Diseases/transmissionABSTRACT
In Brazil, homeopathy was implemented in the Public Health Service through the National Policy on Complementary and Integrative Practices of the Health Ministry, published in 2006. Homeopathy appears as a very interesting therapy to be used in the Public Health Services since its medicines are compounded at a very low cost. Considering this interesting scenario to develop research in the Public Health, the Family Health Program (FHP) in Petropolis and the Faculty of Pharmacy at UFRJ started a partnership with the Roberto Costa Institute.(AU)
No Brasil, a homeopatia foi implementada no Serviço Público de Saúde, através da Política Nacional de Práticas Integrativas e Complementares do Ministério da Saúde, publicada em 2006. A homeopatia surge como uma terapia muito interessante para ser usada no serviço público de saúde uma vez que seus medicamentos tem um custo muito baixo. Considerando este cenário interessante para desenvolver uma pesquisa em Saúde Pública, o Programa de Saúde da Família (PSF) de Petrópolis e a Faculdade de Farmácia da UFRJ iniciaram uma parceria com o Instituto Roberto Costa. (AU)
Subject(s)
Humans , Biotherapics , Homeopathic Pharmaceutical Complex , Respiratory Tract InfectionsABSTRACT
Biotherapics are homeopathic remedies prepared from organic products that are chemically undefined and can be used for treatment of diseases like influenza. There are several classes of biotherapics and, among these, there are some called "living biotherapics" or "Roberto Costa?s Biotherapics". This study aimed to compare the cellular and biochemical effects of biotherapics prepared from intact influenza virus diluted in water and the one obtained from the same viral sample inactivated by ethanol 70% (v / v), both in the potencies of 12x and 30x. Transmission electron microscopy (TEM) analyses were performed on both preparations to assess the integrity of viral particles, which showed that ethanol 70% (v/v) induced a complete denaturation of viral particles. In contrast, the integrity of virus particles was preserved when water was used as the biotherapic solvent. Cellular and biochemical alterations induced by the preparations on MDCK cells were analyzed and compared with those induced by respective controls (water 30x-treated and untreated cells). Cellular viability analyzed by MTT method showed statistically significant differences (p <0.05) in MDCK cells treated with intact biotherapic for 5 (3 stimuli) and 30 (18 stimuli) days in comparison with untreated control. TEM analysis did not show significant cellular changes when the different experimental groups were compared. The enzymatic activity of phosphofructokinase 1 (PFK), an important enzyme in the glycolytic pathway, presented a statistically significant increase (p <0.05) after 30 days of treatment when compared to control groups. The results obtained suggest that inactivation of viral sample with ethanol 70% induces lysis and disruption of viral particles. In addition, preliminary results indicated that treatment with intact biotherapic seems to induce higher variations on MDCK cells responses when compared to inactivated-biotherapic-treated cells. Further analyses are ongoing, including scanning electron microscopy and quantification of the number of mitosis, in order to elucidate the mechanisms involved with biochemical and cellular responses induced by theses biotherapics.(AU)
Subject(s)
Alphainfluenzavirus , BiotherapicsABSTRACT
Strains of macrophages, such as murine J774.G8 macrophages, are susceptible to influenza A infection [1]. One of the responses to viral infection involves the production of various types of immunostimulatory cytokines by infected cells [2].In all cases, there were no significant differences compared to control groups. However, the production of TNF-? detected in macrophages treated by intact and inactivated biotherapics presented a tendency to increase after infection. In fact, similar results were previously detected in other experiments conducted only with the intact biotherapic [3]. The release of the cytokine MCP1 in all experimental situations presented a tendency to decrease after the viral infection when compared to untreated macrophages. No statistically significant difference was detected in the production of IL 12 and IL 10. These experiments will be repeated to confirm the data obtained.(AU)
Subject(s)
Cytokines , Macrophages , BiotherapicsABSTRACT
In Brazil, homeopathic medicines are prepared according to the Homeopathic Pharmacopeia, regulated by ANVISA. Among several categories of medicines, there is the biotherapic group, which is prepared from etiologic agents. In this study, we developed a biotherapic from influenza A virus, aiming the influenza infection prevention. Influenza is a disease that affects thousands of people worldwide every year, with an important economic impact, what motivates the development of new low cost therapies. The H3N2 biotherapic developed in this study was administered to Balb/c mice to evaluate their immune response to viral specific antigens and behavior (homeopathic proving). Sixty-two 4 weeks old Balb/c mice were divided into five experimental groups (n=14 per group), after approval by the Ethics Committee of Animal Use (Protocol DFBCICB 037) and stimulated daily, blindly, with 1% (v/v) different homeopathic medicines, for a maximum period of 42 days. The tested medicines were: biotherapic 30x prepared from inactivated influenza A virus; biotherapic 30x prepared with infectious influenza A virus; and thymulin 5cH, a thymus hormone. The two control groups were treated with water 30x and nothing (baseline group). After 21 days of treatment, half of the animals from each group was challenged subcutaneously with the viral hemagglutinin antigen (7 g / 200 L) and monitored by 21 days further, to evaluate the humoral immune response and general behavior, using an open device. The remaining animals were evaluated by the same behavioral tests at the end of the first 21 days, as an attempt to define the proving features. After euthanasia, all animals were autopsied and the spleen, lungs, heart and mediastine lymph nodes were weighed. Histometry of the spleen follicles was also made. Histopathological and behavioral analyses showed absence of behavioral effects, however, there was increase of spleen lymphoid follicles diameter in immunized animals treated with thymulin and with the biotherapic prepared from infectious influenza A, when compared to the control group. This experiment is being repeated using flow cytometry to complete the analysis and confirm the results.(AU)
Medicamentos homeopáticos são preparados de acordo com a farmacotécnica homeopática regulamentada pela ANVISA. Dentre as várias categorias destes medicamentos, destaca-se o grupo dos bioterápicos, medicamentos que são preparados a partir do próprio agente etiológico. No presente estudo, foi desenvolvido um bioterápico a partir do vírus influenza A, visando a profilaxia da gripe. A gripe é uma doença que atinge milhares de pessoas anualmente em todo o mundo e o desenvolvimento de novas terapias para esta doença vem sendo estimulado com frequência. O bioterápico desenvolvido foi administrado a camundongos do tipo Balb/c para avaliação da resposta imune e comportamental. Para tanto, sessenta e dois camundongos Balb/c com 4 semanas de vida foram separados em cinco grupos experimentais, após aprovação pelo Comitê de Ética de Uso de Animais (Protocolo DFBCICB 037) e estimulados diariamente, de maneira cega, por diferentes soluções homeopáticas, na concentração de 1% (V/V), durante um prazo máximo de 42 dias. Três medicamentos homeopáticos foram testados: bioterápico contendo o vírus influenza A inativado 30DH; bioterápico contendo o vírus influenza A íntegro 30DH; timulina 5CH. Um grupo controle foi tratado com água 30x e o outro não recebeu tratamento. Após 21 dias de tratamento, metade dos animais de cada grupo (31 animais) foi desafiada, por via subcutânea, com o antígeno viral hemaglutinina na concentração de 7 g/ 200L e acompanhados por mais 21 dias para avaliação da resposta imune humoral e do comportamento, pela técnica do campo aberto. Os animais restantes foram submetidos aos mesmos testes ao final dos primeiros 21 dias de tratamento, antes do desafio antigênico. Após a eutanásia, todos os animais foram necropsiados e o baço, o pulmão, o coração e o linfonodo mediastínico foram colhidos para análise de peso e histometria do baço. As análises histopatológica e comportamental mostraram a ausência de efeitos patogenéticos perceptíveis neste modelo experimental, mas houve aumento da reatividade dos folículos linfóides do baço nos animais desafiados antigenicamente e tratados com bioterápico de influenza A íntegro e timulina, em relação ao grupo controle. Este experimento está sendo repetido(AU)
Subject(s)
Animals , Mice , Orthomyxoviridae , Influenza, Human , Biotherapics , Homeopathic RemedyABSTRACT
Heteroduplex mobility assay, single-stranded conformation polymorphism and nucleotide sequencing were utilised to genotype human parvovirus B19 samples from Brazil and Paraguay. Ninety-seven serum samples were collected from individuals presenting with abortion or erythema infectiosum, arthropathies, severe anaemia and transient aplastic crisis; two additional skin samples were collected by biopsy. After the procedure, all clinical samples were classified as genotype 1.
Subject(s)
Female , Humans , Pregnancy , Heteroduplex Analysis/methods , Parvoviridae Infections , Polymorphism, Single-Stranded Conformational , Base Sequence , Brazil , Genotype , Molecular Sequence Data , Paraguay , Pregnancy Complications, InfectiousABSTRACT
Introduction: Influenza viruses have been responsible for highly contagious acute respiratory illnesses with high mortality, mainly in the elderly, which encourages the development of new drugs for the treatment of human flu. The biotherapics are medicines prepared from biological products, which are not chemically defined. They are compounded following the homeopathic procedures indicated for infectious diseases with known etiology [1]. Aim: The purpose of the present study is to verify cellular alterations induced by a biotherapic prepared from the infectious influenza A virus. Methodology: This biotherapic was prepared for this study in the homeopathic potency of 30X according to the Brazilian Homeopathic Pharmacopeia [2]. The concentration of 10% was not cytotoxic to cells, as verified by neutral red assay. The cellular alterations observed in MDCK cells were analyzed by optical microscopy for the quantification of mitosis, nucleoli and lipid bodies. The mitochondrial activity was assessed by MTT assay and the phosphosfructokinase-1 (PFK-1) enzyme activity was analyzed on the MDCK cells treated for 5, 10 and 30 days. Macrophages J778.G8 were treated with this biotherapic to evaluate the immunostimulatory cytokine release. Results: The cellular alterations observed in MDCK cells were verified by optical microscopy. The number of lipid bodies present in MDCK cells stimulated for 10 days was significantly lower (p <0.05) when compared to controls. The biotherapic significantly increased (p <0.05) the number of mitosis and the mitochondrial activity of MDCK cells stimulated for 10 and 30 days. These changes were confirmed by a significant reduction (p <0.05) on the PFK-1 activity. These results suggest that the biotherapic was able to activate the Krebs cycle and pentosephosphate metabolism to the generation of amino acids and nucleotides, situations common to cells whose rate of mitosis is increased. The quantification of immunostimulatory cytokines by macrophages J774.G8 indicated that the tumor necrosis factor (TNF-?) production was higher (p <0.05) in the supernatant of the macrophages pre-treated with this biotherapic and infected with influenza virus, suggesting an activation of the macrophages by this biotherapic. Conclusion: This biotherapic is able to induce some cellular alterations, which show strong evidence that it might be a promising option for the human flu. New experiments are being developed to understand the mechanisms of action of this biotherapic.(AU)
Subject(s)
Influenza, Human , Complementary TherapiesABSTRACT
Introduction: Influenza viruses have been responsible for highly contagious acute respiratory illnesses with high mortality, mainly in the elderly, which encourages the development of new drugs for the treatment of human flu. The biotherapics are medicines prepared from biological products, which are not chemically defined. They are compounded following the homeopathic procedures indicated for infectious diseases with known etiology [1]. Aim: The purpose of the present study is to verify cellular alterations induced by a biotherapic prepared from the infectious influenza A virus. Methodology: This biotherapic was prepared for this study in the homeopathic potency of 30X according to the Brazilian Homeopathic Pharmacopeia [2]. The concentration of 10% was not cytotoxic to cells, as verified by neutral red assay. The cellular alterations observed in MDCK cells were analyzed by optical microscopy for the quantification of mitosis, nucleoli and lipid bodies. The mitochondrial activity was assessed by MTT assay and the phosphosfructokinase-1 (PFK-1) enzyme activity was analyzed on the MDCK cells treated for 5, 10 and 30 days. Macrophages J778.G8 were treated with this biotherapic to evaluate the immunostimulatory cytokine release. Results: The cellular alterations observed in MDCK cells were verified by optical microscopy. The number of lipid bodies present in MDCK cells stimulated for 10 days was significantly lower (p <0.05) when compared to controls. The biotherapic significantly increased (p <0.05) the number of mitosis and the mitochondrial activity of MDCK cells stimulated for 10 and 30 days. These changes were confirmed by a significant reduction (p <0.05) on the PFK-1 activity. These results suggest that the biotherapic was able to activate the Krebs cycle and pentosephosphate metabolism to the generation of amino acids and nucleotides, situations common to cells whose rate of mitosis is increased. The quantification of immunostimulatory cytokines by macrophages J774.G8 indicated that the tumor necrosis factor (TNF-?) production was higher (p <0.05) in the supernatant of the macrophages pre-treated with this biotherapic and infected with influenza virus, suggesting an activation of the macrophages by this biotherapic. Conclusion: This biotherapic is able to induce some cellular alterations, which show strong evidence that it might be a promising option for the human flu. New experiments are being developed to understand the mechanisms of action of this biotherapic.
Subject(s)
Biotherapics , Influenza, Human/immunologyABSTRACT
A atividade sialidásica do vírus influenza tem uma atividade essencial sobre glicoproteínas celulares, permitindo a disseminação de infecções virais por prevenir a auto-agregação entre partículas virais e a re-ligação vírus-célula. Duas amostras variantes purificadas de vírus influenza A/Memphis/102/72 (H3N2), reconhecidas por sua atividade de ligação a receptores apresentando estruturas como a2,6 ou a2,3-sialilactose, foram analisadas por sua atividade sialidásica sobre diferentes substratos naturais e artificiais. A amostra M1/5 mostrou maior atividade sialidásica sobre fetuína (D.O.=0,226), MPN (D.O.=0,110) e eritrócitos humanos (10.240 unidades hemaglutinantes/ml), enquanto a atividade da amostra M1/5HS8 foi expressa por D.O.=0,129, D.O.=0,065 e 2.560 unidades hemaglutinantes/ml quando usados, respectivamente, fetuína, MPN e eritrócitos humanos como substratos. Contudo a amostra M1/5HS8 exibiu uma atividade sialidásica mais significativa sobre mucina quando comparada à amostra M1/5; a atividade enzimática da primeira amostra foi responsável pela liberação de 3,5 nmol de ácidos siálicos livres, enquanto a última produziu 16,5 nmol de ácidos siálicos livres.
Subject(s)
Virus Diseases , Glycoproteins/analysis , Neuraminidase , Substrates for Biological Treatment/analysisABSTRACT
Desde os tempos mais remotos, os vírus influenza têm sido o agente causal de doenças respiratórias letais. O seu processo de replicação ocorre nas células epiteliais do trato respiratório, causando uma síndrome respiratória aguda, na qual as glicoproteínas hemaglutinina (HA) e hemaglutinina-esterase-fusão (HEF), ancoradas na superfície dos vírus influenza A e C, respectivamente, são responsáveis pelos processos de fusão durante o ciclo de replicação viral. Ao contrário dos processos de adsorção, sialidase e esterase, atividades inatas desempenhadas por estas mesmas estruturas, a fusão depende de uma glicosilação e clivagem protéica prévias, para que o vírus se torne infeccioso. A glicosilação das proteínas de superfície está associada principalmente com a antigenicidade e com a estabilidade das proteínas de fusão. O presente trabalho analisa a influência da de-glicosilação sobre a atividade de fusão, usando vírus influenza A e C como modelos de estudo. A de-glicosilação parcial provocou significativa redução da atividade fusogênica, induzindo uma redução de 51,0 por cento, 87,5 por cento, 95,5 por cento e 79,3 por cento em relação às amostras de vírus influenza A/Memphis/102/ 72, A/FM/1/47, C/Taylor/1233/47 e C/Paris/1/67, respectivamente, acarretando também eventuais aumentos desta atividade biológica para certas amostras: 10,15 por cento (pH 5,8), 59,47 por cento (pH 5,8), 32,55 por cento (pH 5,8) e 80,7 por cento (pH 5,4) com relação às amostras de vírus influenza A/Memphis/102/72, A/FM/1/ 47, C/Taylor/1233/47 e A/Paris/1/67, respectivamente. Os resultados permitem concluir que o nível de glicosilação mostra-se estreitamente relacionado com a estabilidade das proteínas, causando o processo deglicosilação uma influência significativa sobre a atividade fusogênica viral.
Subject(s)
Hemagglutinin Glycoproteins, Influenza Virus , Alphainfluenzavirus , Betainfluenzavirus , Respiratory Tract Diseases , GlycosylationABSTRACT
A existência e o caráter de variantes ou subpopulaçöes derivadas de uma amostra padräo de vírus Sendai foram estudados, usando duas amostras de vírus Sendai selecionadas por técnica baseada na atividade de ligaçäo e receptores, a qual é apresentada por aqueles vírus. Foram estudados o comportamento biológico da neuraminidase de duas diferentes amostras Sendai de vírus parainfluenza tipo 1, sua pH-dependência, cálcio-dependência e relaçäo com as capacidades hemaglutinante e hemolítica. Foi observado que ambas as amostras, aquela considerada como semelhante à padräo e aquela obtida por propagaçäo de subpopulaçäo adsorvida à eritrócitos, mostravam mais significativas atividades hemaglutinante e sialidásica em valores de pH entre 5.0 e 7.0. A amostra considerada como semelhante à padräo, embora näo mostrasse qualquer atividade hemaglutinante frente a hemácias humanas do grupo O, era capaz de mostrar uma atividade sialidásica significativa. A atividade sialidásica revelava cálcio-dependência e relacionamento com a atividade hemolítica. A baixa taxa de hemólise exibida poderia ser explicada pela eficiente atividade sialidásica de estruturas HN sobre receptores celulares, os quais seriam essenciais para o processo de fusäo. As amostras mostravam caráteres diferentes quanto às atividades hemaglutinante e sialidásica, o que sugeriu que a seleçäo de diferentes variantes ou subpopulaçöes, uma observaçäo já feita por alguns autores, seria muito importante de ser compreendida, para um eficiente direcionamento dos processos de diagnóstico e de seleçäo de amostras virais vacinais
Subject(s)
Parainfluenza Virus 1, Human/physiology , Neuraminidase/classification , Hemagglutination Tests/classificationABSTRACT
Amostras de vírus da Doença de Newcastle (cepas SO-93, B1 e La Sota) e da Influenza (cepa A/PR/8/34 (H1N1) foram analisadas especificamente quanto à presença de carboidratos específicos, de comprovada importância no processamento das atividades biológicas virais. As amostras virais foram concentradas por sedimentaçäo, avaliadas quanto ao seu teor proteico e título hemaglutinante e, entäo, estudadas quanto aos seus resíduos carboidratos. O estudo realizado com uso de lectinas e açúcar específico (inibidor de Concanavalina A) revelou a importância e especificidade do caráter carboidratado de estruturas peptídicas de superfície viral, o que pode ser observado através da inibiçäo do aparecimento das linhas de precipitaçäo entre Concanavalina A e soro específico para vírus da Doença de Newcastle
Subject(s)
Orthomyxoviridae/isolation & purification , Concanavalin A/analysis , Influenza, Human/microbiology , Newcastle Disease/microbiologyABSTRACT
A atividade de fusäo, depende de pH, de uma amostra aviária de Vírus Influenza A com eritrócitos de galinhas, foi investigada usando oteste de hemólise (HL). Este teste é baseado na quantificaçäo de hemoglobina (Hb) liberada como consequência da fusäo vírus/eritrócito. A atividade hemolítica desta preparaçäo viral pode ser demonstrada na faixa de pH ácido (5.0-5.8), o que está relacionado à ocorrência de uma mudança conformacional nas moléculasda hemaglutinina (HA) sob estas condiçöes. A atividade fusogênica era rapidamente inativada após incubaçäo do vírus, em pH ácido, a 37 graus C, na ausência de eritrócitos, sugerindo que a mudança conformacional da HA do vírus pode ser responsável pela ativaçäo e/ou inativaçäo da capacidade fusogênica. O estudo da reaçäo de HL mostra que elevando-se a concentraçäo de eritrócitos, enquanto a concentraçäo de vírus permanece constante, pode-se observar um aumento na liberaçäo de hemoglobina (Hb), o qual sugere que, provavelmente, os vírus tiveram a chance de encontrar um maior número de células susceptíveis. Uma vez que a Hb em soluçäo muda de tonalidade em funçäo do pH em que se encontra, um fator de correçäo foi utilizado após o ensaio colorimétrico.
Subject(s)
Animals , Hemoglobins , Erythrocytes , Gene Fusion/methods , Influenza A virus/chemistryABSTRACT
O estudo de vigilância virológica de uma comunidade de pássaros num período de três anos, resultou no isolamento de 21 amostras de vírus da doença de Newcastle (NDV), entre 360 materiais fecais examinados. Estes isolamentos ocorreram de maio a setembro e de novembro a janeiro, com mais alta percentagem nos primeiros dois anos de investigaçäo (1981/82 e 1982/83). Os pássaros aparentemente saudáveis tiveram suas fezes coletadas e a presença viral foi investigada pela inoculaçäo em ovos embrionados. Os vírus isolados foram identificados pro inibiçäo de hemaglutinaçäo (HI)
Subject(s)
Animals , Newcastle disease virus/isolation & purification , BirdsABSTRACT
Os pássaros aparentemente saudáveis, durante o período de investigaçäo, tiveram suas fezes coletadas e inoculadas em ovos embrionados. A identificaçäo dos isolados foi feita por teste de imunodifusäo dupla (DI), inicibiçäo de hemaglutinaçäo (HI) e inibiçäo de neuraminidase (NI). O estudo de uma comunidade de aves ornamentais resultou no isolamento de 11 amostras de vírus Influenza A, subtipos H6N2 e H7N1, em 360 amostras de fezes examinadas. Casos de isolamentos ocorreram de Maio a Setembro e de Novembro a Janeiro. Eles mostraram relaçäo sorológica com amostras A/Hong Kong/68 e A/FM/1/47 com fórmula antigênica H3N2 e H1N1, respectivamente