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Coastal ecotones can disrupt natural conditions, yielding intricate ecological contexts where salinity plays a variable role. The aim of this study was to assess the salinity effect on three species representatives of semifixed dune (Crucianella maritima, Helianthemum caput-felis and Teucrium dunense). Field data were collected to assess plant cover in semifixed dunes, ecotone with other coastal habitats, and artificial Posidonia oceanica wracks. Soil samples were collected, and conductivity measured. Then, experimental exposure to salinity was conducted with 6 seawater (SW) treatments (Control, 6.25 % SW, 12.5 % SW, 25 % SW, 50 % SW, 100 % SW). Flowering, gas exchange, chlorophyll fluorescence and enzymatic antioxidant measurements were conducted after two months of exposure. In the field trial, species presence varied depending on the habitat and was null on P. oceanica. The relation between conductivity and species abundance showed moderate tolerance for the three species. For C. maritima this relation was variable depending on the habitat. Experimental data suggest moderate tolerance with stress occurring at 25 % SW onwards. Gas exchange response to salinity was similar among species, but more drastic reduction in assimilation rate and larger decrease in water use efficiency was observed for C. maritima. Instead, photoinhibition occurred in H. caput-felis and T. dunense but was absent in C. maritima likely related to the fact that H. caput-felis and T. dunense activated catalase and superoxide dismutase enzymes, while C. maritima showed activation of glutathione-related enzymes. Malondialdehyde (MDA) increased in C. maritma and decreased for the other species indicating a more complex involvement of MDA under stress conditions. Flowering response to salinity was overall more resilient in T. dunense. Our results, based on field conductivity data and measurements of physiological, antioxidant, and reproductive traits, delineate specific tolerance differences and strategies towards salinity for Mediterranean semifixed dune species.
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Objective This retrospective study aims to present the audiologic outcomes of patients aged 18 years and above who underwent treatment for sudden sensorineural hearing loss (SSNHL) at the tertiary Hospital Central Sur Petróleos Mexicanos in Mexico City, Mexico, between January 2000 and December 2015. Main outcome measures The main outcome measures were patient demographics (age, sex, comorbidities) time from symptom onset to diagnosis and treatment initiation, initial threshold, treatment details (type, dosage, duration), adverse effects, audiometry at diagnosis and at the end of treatment, follow-up duration, and pure-tone average. Results A total of 72 patients were included, with a mean follow-up duration of four months. Comorbidities such as type 2 diabetes mellitus, hypertension, and hypertriglyceridemia were observed in a significant portion of patients. However, these conditions and the use of salvage therapy and adjuvant drugs did not impact hearing recovery. A longer delay from symptom onset to medical attention was associated with a lower gain in decibels (p=0.307). Diabetic patients who received steroid treatment showed a significant gain of at least 15 dB, indicating the greatest benefit in this subgroup. Conclusions Adjuvant drugs may be unnecessary and ineffective in treating SSNHL. Metabolic disorders may be linked to the development of SSNHL. Steroid treatment is the only effective therapeutic option for improving hearing recovery in diabetic patients. Early initiation of treatment after symptom onset is crucial for maximizing auditory recovery.
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Norovirus (NoV) is the main cause of gastroenteritis outbreaks worldwide. Although NoV spreads mainly from person to person, it is estimated that a large proportion of NoV outbreaks are caused by foodborne transmission. Bivalve mollusks are one of the most important foods involved in NoV transmission to humans. Little is known about NoV prevalence in shellfish harvested and commercialized in Brazil. The aim of this study was to map, for the first time, the distribution of NoV contamination in oysters and mussels harvested and commercialized in the coast of Pernambuco state, northeast Brazil. A total of 380 mollusks (260 oysters and 120 mussels) were collected between February and August 2017 either directly from harvesting areas or obtained from beach vendors at 17 sites in Pernambuco. Samples were processed and tested for NoV contamination using a SYBR Green real-time PCR assay. All samples were negative for NoV GI or GII contamination, suggesting a low risk of NoV contamination from this food source during the study period. Additional surveys in different areas of the Brazilian coast are warranted to monitor the risk of NoV infection upon seafood consumption.
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Humanos , Animais , Norovirus/genética , Frutos do Mar , Brasil/epidemiologia , Contaminação de Alimentos/análise , Alimentos MarinhosRESUMO
Introduction: Video capsule endoscopy (VCE) is a useful test for the evaluation of the small bowel mucosa. The main complication of VCE is retention, so in patients with risk factors it is recommended to evaluate the permeability of the digestive tract with Patency Capsule (PC). We describe patients evaluated with PC before the study with VCE. Methods: Descriptive observational study of 96 patients referred for VCE. A clinical survey and images identified that 7 of these patients (7.3%) had retention risk factors, so they were previously requested PC. Results: 2 of the 7 patients evaluated with PC did not excrete the device, so the use of VCE was contraindicated; the subsequent study concluded Crohn's disease (CD) and jejunal stenosis due to retractable mesenteritis in these cases. Of the remaining 89 patients, not evaluated with PC, 1 (1.1%) developed retention of the VCE at an ulcerated stenosis, and was subsequently diagnosed as CD. Conclusion: In our study, we confirmed the usefulness of PC as a method to assess the risk of retention of VCE in patients with risk factors for ID stenosis.
Introducción: La video-cápsula endoscópica (VCE) es un examen útil para el estudio de patologías del intestino delgado (ID). La principal complicación de la VCE es la retención, por lo que en pacientes con factores de riesgo se recomienda evaluar la permeabilidad del tubo digestivo con Cápsula Patency (CP). Se presenta una serie de casos evaluados con CP previo al estudio con VCE. Métodos: Estudio observacional descriptivo de 96 pacientes derivados para realización de VCE. Mediante encuesta clínica e imágenes se identificó que 7 de estos pacientes (7,3%) tenían factores de riesgo de retención, por lo que se les solicitó previamente CP. Resultados: 2 de los 7 pacientes evaluados con CP no expulsaron el dispositivo por lo que se contraindicó el uso de VCE; el estudio posterior concluyó Enfermedad de Crohn (EC) y estenosis yeyunal por mesenteritis retráctil en estos dos casos. De los 89 pacientes restantes, no evaluados con CP, 1 (1,1%) presentó retención de la VCE a nivel de una estenosis ulcerada diagnosticada posteriormente como EC. Conclusión: En nuestra casuística se confirma la utilidad de la CP como un método para evaluar el riesgo de retención de VCE en pacientes con factores de riesgo de estenosis de ID.
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Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Cápsulas Endoscópicas/efeitos adversos , Obstrução Intestinal/etiologia , Obstrução Intestinal/prevenção & controle , Intestino Delgado/patologia , Estudos Retrospectivos , Corpos EstranhosRESUMO
The Infectious Bursal Disease Virus (IBDV) causes immunosuppression in young chickens. Advances in molecular virology and vaccines for IBDV have been achieved by viral reverse genetics (VRG). VRG for IBDV has undergone changes over time, however all strategies used to generate particles of IBDV involves multiple rounds of amplification and need of in vitro ligation and restriction sites. The aim of this research was to build the world's first VRG for IBDV by yeast-based homologous recombination; a more efficient, robust and simple process than cloning by in vitro ligation. The wild type IBDV (Wt-IBDV-Br) was isolated in Brazil and had its genome cloned in pJG-CMV-HDR vector by yeast-based homologous recombination. The clones were transfected into chicken embryo fibroblasts and the recovered virus (IC-IBDV-Br) showed genetic stability and similar phenotype to Wt-IBDV-Br, which were observed by nucleotide sequence, focus size/morphology and replication kinetics, respectively. Thus, IBDV reverse genetics by yeast-based homologous recombination provides tools to IBDV understanding and vaccines/viral vectors development.
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Animais , Embrião de Galinha , Recombinação Homóloga , Vírus da Doença Infecciosa da Bursa/genética , Genética Reversa/métodos , Brasil , Células Cultivadas , Fibroblastos/virologia , Vetores Genéticos , Instabilidade Genômica , Vírus da Doença Infecciosa da Bursa/isolamento & purificação , Vírus da Doença Infecciosa da Bursa/fisiologia , Saccharomyces cerevisiae/genética , Transfecção , Cultura de Vírus , Replicação ViralRESUMO
Many students may read fluently but have difficulties constructing meaning from texts. Difficulties with reading comprehension have many implications at school. In particular, problems understanding texts interfere with studying and learning from text. Reading comprehension has improved in the last 30 years focusing on intervention programs that work with strategies in which metacog-nition plays a crucial role. However, recent years have seen relevant advances in the study of the relationship between working memory (WM), particularly executive processes, and reading comprehension. In this paper, we present how the last 20 years of our research has evolved regarding metacognitive intervention from text comprehension strategies, as the main idea and summarization to the intervention on WM's executive processes during reading. Thus, our more recent empirical data has shown that text comprehension can be improved after specific training on the executive functions of working memory (e.g., focusing, switching, connecting and updating mental representations, and the inhibition of irrelevant information) in Primary school students.
Muchos estudiantes pueden leer de forma fluida pero presentan dificultades para construir significados a partir de los textos. Las dificultades de compresión lectora tienen varias implicaciones en la escuela. En particular, los problemas de comprensión de textos interfieren con el estudio y el aprendizaje desde el texto. La comprensión de lectura se ha mejorado en los últimos 30 años enfocándose en los programas de intervención que trabajan con estrategias en las cuales la metacognición juega un papel crucial. Sin embargo, en años recientes han sido relevantes los avances en el estudio de las relaciones entre la memoria de trabajo (WM), particularmente el proceso ejecutivo, y la comprensión de lectura. En este artículo presentamos la manera como se ha desarrollado nuestra investigación en los últimos 20 años, en relación con intervención metacognitiva desde las estrategias de comprensión de textos, tales como la idea principal y el resumen en la intervención sobre el proceso ejecutivo de WM durante la lectura. Así, nuestros datos empíricos recientes han mostrado que la comprensión de textos puede ser mejorada después del tratamiento específico sobre las funciones ejecutivas de memoria de trabajo (e.g., enfocándose, cambiando, conectando y actualizando las representaciones mentales y la inhibición de información irrelevante) en niños de escuela primaria.
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Ciência Cognitiva , CompreensãoRESUMO
Objetivos: Evaluar la frecuencia de alteración tiroidea y los factores asociados en los pacientes con VIH/SIDA de un hospital universitario en Colombia. Pacientes y Métodos: Estudio tipo corte transversal de pacientes con VIH/SIDA durante el periodo de 2007 a 2008. Se registró niveles hormonales, inmunológicos, carga viral y tratamiento anti-retroviral. Resultados: En 636 pacientes la prevalencia de hipotiroidismo (TSH > 4,6 μUI/mL) fue de 15,5 por ciento (100/636). El análisis independiente demostró relación significativa para el uso de nevirapina (RR 1,6; IC 95 por ciento 1,1 - 2,3) y estavudina (RR 1,5; IC 95 por cientoo 1 - 2,3). Conclusiones: La prevalencia de hipotiroidismo fue alta y se relacionó con el uso de nevirapina.
Introduction: The objective of this study was to evaluate the frequency of thyroid function alterations and its associated factors in a group of patients from a university hospital in Colombia. Methods: From June 2007 through June 2008, 636 HIV patients were followed in order to assess the relation of thyroid function with the use of HAART. Results: The overall prevalence of hypothyroidism (TSH > 4.6 μUI/mL) was 15.5 percent (100/636). The association of hypothyroidism in the independent analysis showed significant relation only for the use of nevirapine (RR 1.6; CI 95 percent 1.1- 2.34) and stavudine (RR 1.5; CI 95 percent, 1 - 2.3). Conclusions: The prevalence of hypothyroidism was surprisingly high among the studied population.
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Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Fármacos Anti-HIV/efeitos adversos , Infecções por HIV/tratamento farmacológico , Hipotireoidismo/induzido quimicamente , Nevirapina/efeitos adversos , Estavudina/efeitos adversos , Terapia Antirretroviral de Alta Atividade , Estudos de Coortes , Colômbia , Estudos Transversais , Hospitais Universitários , Hipotireoidismo/diagnóstico , Tireotropina/sangue , Carga ViralRESUMO
El cáncer de colon durante la gestación es una patología poco frecuente, con una incidencia entre el 0,07 y el 0,1 por ciento. El diagnóstico precoz es complejo y el pronóstico suele ser malo por tratarse con frecuencia de procesos en estado avanzado. Presentamos el caso de una paciente de 38 años, diagnosticada de ade-nocarcinoma de colon transverso metastásico en la semana 31 de gestación. Realizamos una revisión en relación al diagnóstico y manejo de esta patología.
Colonic cancer during pregnancy is a rare event, whit incidence between 0.07 and 0.1 percent. Early diagnosis is difficult and prognosis is severe as it generally made at an advanced stage. We report a case of metastasic adenocarcinoma of the transverse colon in a 38-year-old pregnant patient diagnosed at 31 weeks of gestation. The problem of diagnosis as well as management of this pathology is discussed.
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Humanos , Adulto , Feminino , Gravidez , Recém-Nascido , Adenocarcinoma/cirurgia , Adenocarcinoma/patologia , Complicações Neoplásicas na Gravidez/cirurgia , Complicações Neoplásicas na Gravidez/patologia , Neoplasias do Colo/cirurgia , Neoplasias do Colo/patologia , Adenocarcinoma/complicações , Cesárea , Colectomia , Colo Transverso , Complicações Neoplásicas na Gravidez/diagnóstico , Metástase Linfática , Neoplasias Hepáticas/secundário , Neoplasias do Colo/complicações , Resultado da Gravidez , Terceiro Trimestre da Gravidez , PrognósticoRESUMO
Cryptococcal infection is not frequent in immunocompetent patients. The most commonly involved sites are the lungs and the central nervous system. Cryptococcal osteomyelitis occurs in 5-10 percent of patients with disseminated cryptococcosis with few reports of cryptococcal arthritis in elderly adults. We describe the case of a 92-year-old woman with a Cryptococcus neoformans knee joint infection associated to osteomyelitis.
La infección por Cryptococcus neoformans es infrecuente, los sitios más comunes de presentación son pulmón y SNC. La osteomielitis criptococóccica ocurre en 5 a 10 por ciento de los pacientes con criptococcosis diseminada. La mayoría de casos ocurre entre 21 y 59 años de edad, hay pocos reportes de artritis criptococóccica en adultos mayores.
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Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Artrite Infecciosa/microbiologia , Criptococose/diagnóstico , Cryptococcus neoformans/isolamento & purificação , Antifúngicos/uso terapêutico , Artrite Infecciosa/diagnóstico , Artrite Infecciosa/tratamento farmacológico , Criptococose/tratamento farmacológico , Fluconazol/uso terapêuticoRESUMO
We describe the presence of anisakiasis in a patient who had a small hiatal hernia. A 60 year-old women presented general malaise, burning pain, flatulence, persistent nausea and abdominal distension during five days before consulting. She referred that she ate a dish of marinated raw fish with lemon and pepper ("cebiche") and after a few hours the symptoms began. An esophagogastroscopy showed a white colour larva of approximately three cm with the cephalic end partially adhered and localized in the mucosa of the hiatal hernia. During the procedure the worm was easily extracted. The morphologic study of the specimen identified it as a stage IV larva of Pseudoterranova sp. The clinical condition of the patient improved after the extraction of the parasite.
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Animais , Feminino , Humanos , Pessoa de Meia-Idade , Anisaquíase/diagnóstico , Anisakis/isolamento & purificação , Hérnia Hiatal/parasitologia , Anisakis/classificação , LarvaRESUMO
El dorso nasal representa una de las sub-unidades nasales que mayor peso tiene al momento de considerar una nariz armónica o estéticamente ideal, reflejando en conjunto con la proyección de la punta nasal el carácter del perfil facial. Se realizó un estudio prospectivo de un grupo seleccionado de 56 pacientes, con criterio para la realización de rinoplastia primaria, que presentaran cúpulas óseo cartilaginosas prominentes. Se utilizaron como métodos de evaluación la comparación de los parámetros estéticos ideales en los estudios fotográficos preoperatorios y postoperatorios. A un total de 56 pacientes se les realizó resección conservadora de la cúpula óseo cartilaginosa prominente en dos tiempos, a través de la técnica de rinoplastia abierta; a 23 pacientes les fueron practicadas osteotomías medias oblicuas y osteotomías laterales como único procedimiento, en 33 pacientes de manera concomitante se utilizaron injertos separadores en la bóveda cartilaginosa, 32 pacientes recibieron injertos de cartílago desmenuzado septal en el rádix y 41 pacientes recibieron injertos de cartílago desmenuzado en la unión cóndro-ósea. Los autores proponen una escisión conservadora de la cúpula óseo cartilaginosa y abogan por una reconstrucción de la misma en casos seleccionados, además de hacer énfasis en la importancia de establecer inicialmente la altura y proyección de la punta nasal a fin de mantener dorsos nasales altos y dentro de parámetros estéticos ideales.
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Humanos , Masculino , Adulto , Feminino , Fraturas Mandibulares , Nariz , Rinoplastia , Otolaringologia , VenezuelaRESUMO
El tromboembolismo (TE) arterial y venoso, posee una elevada morbimortalidad, siendo en pacientes con enfermedades inflamatorias intestinales (EII) 3-4 veces mayor que la población general, con una prevalencia de un 2-10 por ciento. El mecanismo por el cual la actividad procoagulante está aumentada en las EII es aún desconocido, sin embargo, factores de riesgo como el grado de inflamación de la mucosa han sido descritos. Objetivos: Determinar las características clínicas de TE en un grupo de pacientes con EII. Pacientes y Métodos: Se analizaron de manera retrospectiva los antecedentes clínicos de 16 pacientes con EII que presentaron TE durante su evolución. Se evaluó edad, extensión y grado de actividad de la EII al momento del TE. Resultados: Los pacientes estudiados fueron 13 con colitis ulcerosa (CU) y tres con enfermedad de Crohn (EC), edad promedio 43 años (rango 21-72), ocho mujeres. Once pacientes tenían < 50 años al momento del TE. En CU, nueve pacientes tenían pancolitis, todos con enfermedad activa moderada-severa. En EC, dos pacientes presentaban actividad de la enfermedad al momento del TE. Tres pacientes tenían otra manifestación extraintestinal (MEI), dos de ellos artralgias y uno colangitis esclerosante primaria. Los eventos de TE son: trombosis venosa profunda de extremidades inferiores en 9 casos; TE pulmonar en 3 pacientes, trombosis mesentérica/portal (dos casos), trombosis del seno venoso longitudinal (un paciente), trombosis arteria cerebral (uno) y trombosis de arteria braquial un caso). Quince casos de TE ocurrieron entre una semana y 6 años luego del diagnóstico de EII. Cinco pacientes estaban hospitalizados al momento del TE, dos de ellos después de cirugía por su EII. Ningún paciente estaba recibiendo nutrición parenteral total o tenía catéter venoso central al momento del TE. El estudio de trombofilia realizado en cinco pacientes, no demostró alteraciones características. Todos los pacientes fueron tratados con heparina sin complicaciones, y un paciente falleció por embolia pulmonar. Ningún paciente tenía antecedentes personales o familiares de TE. Conclusiones: El tromboembolismo es otra MEI de las EII que debe ser sospechado. La remisión de la EII pudiera ser el factor más importante en la prevención de estos episodios. El uso de heparina como tratamiento del TE no está contraindicado en estos pacientes, incluso en aquellos con crisis severa con sangramiento intestinal.
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Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Doenças Inflamatórias Intestinais/complicações , Tromboembolia/etiologia , Cérebro , Colite Ulcerativa/complicações , Embolia Pulmonar/etiologia , Doença de Crohn/complicações , Estudos Retrospectivos , Fatores de Risco , Heparina/uso terapêutico , Tromboembolia/diagnóstico , Tromboembolia/tratamento farmacológico , Trombose Venosa/etiologiaRESUMO
Anti-endothelial cell autoantibodies (AECA), first described more then 30 years ago, represent a heterogeneous group of autoantibodies directed against poorly characterized antigens located in endothelial cell membranes, and have been reported in a variety of sistemic diseases. Although most of the target antigens for AECA are still not well identified, and AECA have been considered an epiphenomenon of vascular injury, new evidence suggests a pathogenic role, specially by inducing endothelial cell activation and apoptosis. The presence of AECA has been correlated with disease activity in SLE and systemic vasculitis such as Wegener's granulomatosis, Takayasu arteritis, and behçet's disease, and they could be valuable markers of disease activity. Other potential areas of clinical interest in diseases associated to AECA could be the serum thrombomodulin level, as marker of endothelial cell injury in neuropsychiatric lupus, and other vasculitides; and the determination of anti-heat shock protein antibodies including the Hsp60, as a new, non traditional risk factor for atherosclerosis in patient with lupus.
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Humanos , Autoanticorpos/análise , Autoanticorpos/sangue , Células Endoteliais/imunologia , Apoptose , Sensibilidade e EspecificidadeRESUMO
Serum antibodies against Trypanosoma Cruzi have been observed in 19 percent of the Chilean population. Marked differences in organ involvement have been reported in patients with Chagas disease. Chagas disease is rarely an aetiological factor for achalasia in Chile, which is different from reports in other countries of South America. In contrast, a high incidence of megacolon among these patients have been reported. Aim: To study the incidence of gastric and small intestinal motor disorders among these patients and their relationship to esophageal and colon motility disorders. Patients and Methods: We studied 18 patients, 12 women (mean age 45 years); with positive antibodies against T Cruzi. Seven had radiological evidence of megacolon and no one had radiological or manometric evidence for achalasia. Non specific motor esophageal abnormalities were found in 11 patients. Nine had an abnormal electrocardiogram, suggesting a myocardial disease. A questionnaire for gastrointestinal symptoms, an electrogastrography and a small intestinal motility study, were performed in each patient. Results: All patients had evidences of abnormalities in at least one segment of the digestive tract. Twelve patients had an abnormal electrogastrographic study, with bradygastria as the most common finding. Nine had an abnormal small intestinal manometry with a myophatic pattern evidenced by a decreased amplitude of contractions (18.5±3 mmHg). Also an increased number of clustered contractions was observed. Conclusions: Gastric dysrhythmias and small intestinal motor abnormalities are frequently associated to non specific esophageal motor disorders and megacolon in patients with Chagas disease (Rev Méd Chile 2004; 132: 939-4).
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Adolescente , Adulto , Masculino , Humanos , Feminino , Idoso , Doença de Chagas/fisiopatologia , Motilidade Gastrointestinal/fisiologia , Acalasia Esofágica/fisiopatologia , Chile , Incidência , Intestino Delgado/fisiologiaRESUMO
Three Brazilian isolates of bovine viral diarrhea virus (BVDV), antigenically distinct from the standard North American isolates, were selected to immunize BALB/c mice in order to obtain hybridoma cells secreting anti-BVDV monoclonal antibodies (mAbs). Two hybridoma clones secreting mAbs, reacting specifically with BVDV-infected cells (mAbs 3.1C4 and 6.F11), were selected after five fusions and screening of 1001 hypoxanthine-aminopterin-thymidine-resistant clones. These mAbs reacted in an indirect fluorescent antibody (IFA) assay with all 39 South and North American BVDV field isolates and reference strains available in our laboratory, yet failed to recognize other pestiviruses, namely the hog cholera virus. The mAbs reacted at dilutions up to 1:25,600 (ascitic fluid) and 1:100 (hybridoma culture supernatant) in IFA and immunoperoxidase (IPX) staining of BVDV-infected cells but only mAb 3.1C4 neutralized virus infectivity. Furthermore, both mAbs failed to recognize BVDV proteins by IPX in formalin-fixed paraffin-embedded tissues and following SDS-PAGE and immunoblot analysis of virus-infected cells, suggesting they are probably directed to conformational-type epitopes. The protein specificity of these mAbs was then determined by IFA staining of CV-1 cells transiently expressing each of the BVDV proteins: mAb 3.1C4 reacted with the structural protein E2/gp53 and mAb 6.F11 reacted with the structural protein E1/gp25. Both mAbs were shown to be of the IgG2a isotype. To our knowledge, these are the first mAbs produced against South American BVDV isolates and will certainly be useful for research and diagnostic purposes
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Animais , Camundongos , Bovinos , Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/imunologia , Vírus da Diarreia Viral Bovina/imunologia , Hibridomas , Variação Antigênica , Vírus da Diarreia Viral Bovina/genética , Vírus da Diarreia Viral Bovina/isolamento & purificação , Técnica Indireta de Fluorescência para Anticorpo , Genótipo , Cavalos , Camundongos Endogâmicos BALB C , Proteínas RecombinantesRESUMO
Seqüenciamento e análise filogenética de 17 amostras do vírus da diarréia viral bovina (BVDV) isoladas no Brasil identificaram quatro amostras (23,5 por cento) do genótipo 1a (BVDV-1a), nove amostras (52,9 por cento) do genótipo 1b (BVDV tipo 1b) e quatro amostras (23,5 por cento) do genótipo 2 (BVDV tipo 2). As amostras brasileiras de BVDV tipo 2 apresentaram-se genotipicamente distintas dos BVDV tipo 2 até entäo identificados na América do Norte e Europa, sugerindo pertencerem a um novo subgenótipo. A caracterizaçäo antigênica dessas amostras por neutralizaçäo cruzada revelou reatividade sorológica muito reduzida com cepas vacinais do BVDV. O anti-soro produzido contra três cepas vacinais do BVDV apresentou atividade neutralizante muito reduzida contra várias amostras brasileiras de BVDV tipo 1 e 2. Diferenças de até 128 vezes nos títulos de anticorpos neutralizantes foram observadas entre cepas vacinais e amostras brasileiras do BVDV. Nos testes de soroneutralizaçäo (SN) contra o vírus dos tipos 1 e 2, de 1134 amostras testadas, 280 (24,7 por cento) possuiam anticorpos neutralizantes anti-BVDV e dessas, 215 (76,8 por cento) apresentaram atividade neutralizante contra ambos os vírus, 37 (13,2 por cento) reagiram apenas contra o BVDV tipo 2 e 28 amostras (10 por cento) foram positivas apenas contra o BVDV tipo 1. Esses resultados demonstram que testes de SN utilizando vírus de apenas um genótipo podem resultar em número significativo de falsos-negativos e indica a necessidade da formulaçäo de vacinas com amostras locais de BVDV e/ou contendo vírus dos dois genótipos