RESUMO
Resumen Introducción: La prueba biológica establecida por la Organización Mundial de la Salud para aislar y amplificar el virus de la rabia consiste en inocular vía intracraneal ratones lactantes para detectar signos de rabia en un periodo de 21 días. Objetivo: Constatar el contagio viral en las madres de ratones lactantes inoculados con virus de la rabia. Método: Veintisiete aislados mexicanos de virus de la rabia se inocularon vía intracraneal en ratones lactantes, los cuales fueron observados por 21 días y sus madres, por 60 días. El diagnóstico se llevó a cabo mediante inmunofluorescencia en cerebro. El virus se caracterizó por secuenciación y anticuerpos monoclonales. Resultados: Todas las camadas presentaron rabia entre siete y 15 días posinoculación (p. i.); tres de las 27 hembras (11 %), a los días 33, 37 y 39 p. i. de sus crías. La caracterización viral mostró que las madres se infectaron con la misma variante de sus crías, dos procedían de murciélago hematófago y una de perro. Las camadas que trasmitieron rabia a sus madres fueron nueve individuos. Conclusiones: En la naturaleza, el virus de la rabia podría preservarse mediante la transmisión de los neonatos (más susceptibles de contraer y amplificar el virus) a sus madres.
Abstract Introduction: The biological test established by the World Health Organization to isolate and amplify the rabies virus consists in inoculating lactating mice by intracranial route and detecting rabies signs for 21 days. Objective: To verify viral transmission in mothers of rabies virus-inoculated lactating mice. Method: Twenty-seven Mexican rabies virus isolates were inoculated by intracranial route in lactating mice, which were observed for 21 days. The mothers were observed for 60 days. The diagnosis was established by immunofluorescence in brain tissue. The virus was characterized by sequencing and with monoclonal antibodies. Results: All litters showed rabies at between 7 and 15 days post-inoculation (p. i.). Three of the 27 females (11 %) had developed rabies at days 33, 37 and 39 p. i. of their litters. Viral characterization showed that the mothers were infected with the same variant of their offspring, two of them stemming from hematophagous bat and one from dog. The liters that transmitted rabies to their mothers were nine individuals. Conclusions: In nature, the rabies virus could be preserved by transmission from neonates (more susceptible to contracting and amplifying the rabies virus) to their mothers.
Assuntos
Animais , Feminino , Gravidez , Coelhos , Complicações Infecciosas na Gravidez/virologia , Raiva/transmissão , Vírus da Raiva/isolamento & purificação , Transmissão Vertical de Doenças Infecciosas , Lactação , Animais Recém-Nascidos , México , Camundongos Endogâmicos BALB CRESUMO
Dog overpopulation is a major health problem in developing countries due to the existence of some zoonotic diseases in which dogs act as reservoirs, besides the aggressive events to humans. Distribution, behavior patterns and combined methodologies are needed aspects in the design of successful dog population control programs. Coumestrol is a phytoestrogen which induces alterations in the reproductive male system, when bind to alpha and beta estrogen receptors acting as an agonist or antagonist fashion. Both receptor types also exist in central nerve regions governing sexual behavior of those animals such as the preoptic area, ventro medial nucleous, the amygdala and the olfactory bulb. In this study, 300 μg/kg coumestrol was orally administered to male dogs, once a week for a 4 week period. Dogs were freed for 5 min in a 9 m² area having a recipient containing vaginal discharges from estrous dog females and other similar vessel containing sterile saline solution. Smelling latency time for each recipient, smelling frequency and territory marking in response to stimulus, was recorded. At the end of the test, semen was collected and evaluated. A significative difference (P < 0.005) in smelling latency time and smelling frequency to the vaginal discharge was found; sperm count decreased from 518.4 ± 215.4 × 10(6) to 57.6 ± 50.4 × 10(6) at week 4 and the abnormal sperm morphology increased from 14.7 ± 3.3% at 0 week to 60.0 ± 20%. In conclusion, 300 μg/kg coumestrol given orally to male dogs for 4 weeks induces alterations in the olfactory behavior along with an oligo and teratospermic effect.
La sobrepoblación canina es un problema importante de salud pública debido a la transmisión de enfermedades zoonóticas y las agresiones hacia el humano. En el diseño de programas para controlar la población canina se requiere del conocimiento de su distribución, comportamiento y metodologías combinadas para tener éxito. El coumestrol es un fitoestrógeno que induce alteraciones en el aparato reproductor de los machos al unirse a los receptores estrogénicos alfa y beta, en donde actúa de manera dosis-dependiente como agonista o antagonista. Estos receptores también existen en las estructuras del sistema nervioso que regulan el comportamiento sexual, como la región preóptica, núcleo ventromedial, la amígdala y el bulbo olfatorio. En este estudio se administró coumestrol (300 μg/kg) por vía oral a perros machos, una vez por semana durante cuatro semanas; los perros se colocaron durante cinco minutos en un área aislada de 9 m² en donde se colocó un frasco conteniendo secreciones vaginales obtenidas de perras en estro y otro con solución salina estéril. Se registró el tiempo de latencia de los perros para olfatear cada frasco, su frecuencia de respuesta y la frecuencia con que se presentó conducta de marcaje en respuesta al estímulo. Una vez concluido el experimento, se obtuvo semen y se evaluó. Se encontró diferencia significativa (P < 0.005) en el periodo de latencia y frecuencia con la que el macho se acercó a oler las secreciones vaginales y el conteo espermático disminuyó de 518.4 ± 215.4 × 10(6) al inicio del estudio a 57.6 ± 50.4 × 10(6) en la semana cuatro y el porcentaje de anormalidades espermáticas aumentó de 14.7 ± 3.3 puntos en la semana 0 a 60.0 ± 20.0% en la semana cuatro. Se concluye que el tratamiento de perros con coumestrol durante cuatro semanas ocasiona alteraciones en la conducta de exploración olfatoria y tiene un efecto oligospérmico y teratospérmico.
RESUMO
En este trabajo se presenta el panorama de utilización de los anticuerpos monoclonales (AM) en virología; se discute el papel que han tenido en la exploración de las bases de variabilidad antígénica vital, su utilización en el diagnóstico, en la terapéutica y en la purificación inmunoquímica. Finalmente se analizan algunas futuras aplicaciones
Assuntos
Viroses/imunologia , Anticorpos Monoclonais/imunologia , Antígenos Virais/imunologiaRESUMO
Se discuten resultados obtenidos cultivando la línea de mieloma murino X63 Ag8.6.5.3. en ratones. Las células fueron inoculadas por vía subcutánea y por vía intraperitoneal, utilizando respectivamente ciclofosfamida y radiaciones gamma como agente inmunopresor. El cultivo intraperitoneal produce una mayor proporción de células viables, aptas para la hibridación por la vía subcutánea. Con el pase en ratón, se elimina la contaminación de las células por C. albicans
Assuntos
Animais , Camundongos , Plasmocitoma/patologia , Hibridomas/fisiologia , Replicação Viral , Camundongos Endogâmicos BALB C , Terapia de ImunossupressãoRESUMO
The first step of the herpes virus infection is the attachment to heparan sulfate molecules on the cellular membrane. In order to improve the characterization of this phenomenon, we compared the inhibitory effect of six sulfated polyelectrolytes (PE): heparin, heparan, low molecular wight heparin, chondroitin, dextran and protamine on plaque formation by pseudorabies virus (PRV) were compared. The PE with the highest antiherpetic effect was heparin, followed by dextran sulfate. Heparan sulfate, which has been proposed as the initial receptor of herpes virus on the cell surface showed and effect 100-fold lower than heparin. Comparative inhibition curves of heparin and heparan sulfate against three herpes viruses: herpes simplex virus 1 (HSV-1), HSV 2 and PRV showed similar kinetics of inhibition of plaque formation, suggesting these viruses could share similar cell adsorption mechanisms
Assuntos
Alphaherpesvirinae/efeitos dos fármacos , Antagonistas de Heparina , Heparitina Sulfato/antagonistas & inibidores , Herpes Simples/fisiopatologia , Herpesvirus Suídeo 1/patogenicidade , Polímeros/administração & dosagem , Pseudorraiva/fisiopatologia , Simplexvirus/patogenicidadeRESUMO
Background. The prevention of rabies in Mexico continues to be an importan goal for the health sector. Although the prevalence of this disease continues to fall, between 1990 and 1995 a total of 238 cases were registred (an average of 40 cases annually), with a mean annual incidence of 0.04 cases per 100,000 inhabitants and a mortality of almost 100 percent, so that it is important to rely on highly effective vaccines with few side effects. The objective of this work was to evaluate seroconversion and tolerance to the human diploid cell antirabies vaccine administered to individuals with a history of exposure to rabies, to compare these results with those reported in the literature for the Fuenzalida vaccine, a rabies vaccine produced in the brain tissues of suckling mice, and to find the role antirabies hyperimmune gamma globulin plays in the concentration of post-vaccination antibody concentrations. Methods. An analytical transverse study was carried out in 40 children and adults with a history of rabies exposure who were given a complete, five-dose intramuscular schedule of the human diploid cell rabies vaccine. Subjects were followed daily, and local and systemic signs and symptoms were recorded. Two blood samples (at baseline-and at the end of the ELISA technique, were measured. Results. Adverse side effects produced by the human diploid cell antirabies vaccine, such as frequency of pain, erythema itching, and regional adenopathy were fewer than those reported in the literature for the Fuenzalida vaccine (p < 0.05), and of induration and local pain (p <0.05) in relation to the latter vaccine. All patients seroconverted, producing geometric mean antibody titers of 6.22 IU/mL, an arithmetic mean titer of 9.66 IU/mL with a SD of 9.1 IU/mL. The level of tolerance to the diploid cell vaccine was good and its adverse effects were minimal and fewer than those reported for the Fuenzalida rabies vaccine. Patients receiving the diploid cell vaccine plus antirabies hyperimmune gamma globulin developed higher antibody titers (measured by ELISA test) at the end of the vaccination schedule than those only receiving the vaccine. Conclusions. These results are important in order to achieve an adequate and opportune level of protection provided by prophylactic vaccine to patients with exposure to rabies
Assuntos
Humanos , Criança , Adolescente , Adulto , Anticorpos Antivirais/imunologia , Imunoglobulinas/imunologia , Vacina Antirrábica/imunologia , Raiva/epidemiologia , Raiva/prevenção & controle , Imunização Passiva/métodos , México/epidemiologia , Raiva/epidemiologiaRESUMO
Backgroun. The desing of efficient rabies control programs within a geographic area requires an appropriate knowledge of the local epidemiological cycles. In Latin America, There is a geographical overlap of the two main epidemiological cycles: (a) the terrestrial cycle, where the dog is the main terrestrial vector and the principal cause of human transmission; and (b) the aerial cycle, in which the vampire bat Desmodus rotundus is representative in Mexico. This bat is the major sylvatic rabies vector transmitting rabies to cattle. The purpose of this study was to distinguish between the epidemiological cycles of rabies virus (aerial and terrestrial) circulating in Mexico, using restriction fragment lenght polymorphism (RFLP). Methods. Thirty positive rabies isolates were obtaine from different species (including hummans, domestic, and wildlife animals) and geographical regions. The methodology included the extraction of RNA, and synthesis of cNDA, PCR, and RFLP using four restriction endonucleases. To determine the aerial cycle, Bsa W I and BsrGI were utilized, and for terrestrial cycle, BamH I and Stu I. Most of the samples belonged to the aerial and terrestrial cycles, except for two skunk isolates from Northwestern Mexico, which were not cut by any of the enzymes. Results. Three different migration patterns were detected: (a) the first was observed in six amplicons, which were cut by Bsa W I and BsrGI (aerial cycle); (b) 19 amplified samples were digested with BamH I and Stu I enzymes (terrestrial cycles): and (C) two sking isolates from Northwest Mexico, were not cut by any of the enzymes utilized in the experiments (hypervariable cycle). Conclusions. This concludes that RFLP can be used for the classification of rabies field samples in epidemiological studies. Moreover, it has demonstrated its usefulness, not only for diferentiating between the main epidemiological rabies cycles present in Mexico, but also to detect new cycles in wildlife species
Assuntos
Humanos , Animais , Doenças do Cão/epidemiologia , Polimorfismo de Fragmento de Restrição , Raiva/epidemiologia , Raiva/veterinária , Vetores de Doenças , Cães , México/epidemiologia , PeriodicidadeRESUMO
El género Lyssavirus se divide en los siguientes serogenotipos: Rabia; Lagos bat; Mokola; Duvenhage; EBL 1; y EBL 2. El objetivo de este estudio fue caracterizar con anticuerpos monoclonales (AM) antinucleocápside, virus de rabia aislados de fauna doméstica y silvestre de México, con el fin de verificar si en México sólo se encuentra presente el serotipo 1 (virus de Rabia). Con este propósito se trabajaron 58 aislamientos positivos a rabia a través de inmunofluorescencia directa de 14 diferentes especies domésticas y silvestres de 19 estados de la República mexicana, aquéllas se replicaron en ratones, y posteriormente se procedió a la caracterización con un panel reducido de ocho AM anicucleocáoside que reconoce a todos los serotipos del género Lyssavirus. Los resultados señalan que todas las muestras presentaron similar patrón de reactividad que el serotipo 1. Se concluye que el uso de este panel reducido de AM es de utilidad para una apropiada caracterización del virus de la rabia en el país, ya que permite constatar que en las especies involucradas sólo circula el serotipo 1, lo cual es importante con fines de prevención y control en el manejo de la enfermedad