RESUMEN
Trichinellosis is a zoonotic disease, which represents a significant public health concern in some South American countries, such as Argentina and Chile. Its impact is essentially due to absence of adequate control measures on meat from game animals, as well as the presence of illegal slaughterhouses and the trade of meat products without being tested for this parasite. In Argentina, trichinellosis is an endemic disease. At present, Trichinella spiralis, Trichinella patagoniensis, Trichinella pseudospiralis, and Trichinella britovi have been detected in animals from Argentina. Until now, T. patagoniensis had only been found in mountain cougars (Puma concolor) in Argentina but there is limited information available. The present study intends to determine susceptibility, serological response and distribution of muscle larvae in wild boars infected with T. patagoniensis, T. spiralis and T. pseudospiralis. For each of the Trichinella species five wild boars were inoculated with 20,000 muscle larvae. Except for two specimens which died during the experiment, the animals were euthanized 19 weeks post infection (pi). Blood samples were collected throughout the study in order to determine the antibody kinetics. Also, nine muscle samples from each specimen were taken and analysed for determination of larval distribution. Additionally, four muscle samples were used to obtain muscle juices. Wild boars infected with T. patagoniensis showed little to no larvae in the muscle samples analysed while animals infected with T. spiralis and T. pseudospiralis had a significantly high larval load in all the samples analysed. Optical density (OD) values remained above the cut-off value throughout the experiment. This is the first study to characterize the biological aspects of T. patagoniensis in wild boars.
Asunto(s)
Enfermedades de los Porcinos , Trichinella spiralis , Trichinella , Triquinelosis , Animales , Chile , Larva , Sus scrofa , Porcinos , Triquinelosis/veterinariaRESUMEN
A partir de estudios previos realizados sobre la anatomía del musculo bíceps femoral en el perro y con el objetivo de avanzar en la caracterización inmunohistoquímica y nerviosa de este musculo, estudiamos la existencia de subvolúmenes musculares. Utilizamos la disección roma en piezas musculares aisladas fijadas y tratadas con ácido nítrico al 25%. Las divisiones de las ramas del nervio isquiático involucradas fueron utilizadas como guía en la disección. Se determinaron tres subvolúmenes, uno involucrando a la cabeza caudal y dos en el vientre correspondiente a la cabeza craneal que fueron denominados caudal, proximal y distal respectivamente. Realizamos mediciones del largo de las fibras musculares, dirección, dirección y densidad macroscópica de las mismas para caracterizar los compartimientos. Estos subvolúmenes deberán tenerse en cuanta al realizar estudios electromiográficos del musculo bíceps femoral y al evaluar las alteraciones en la locomoción producto de las alteraciones nerviosas y musculares en el nervio pelviano del canino.
From previous studies on the anatomy of the femoral biceps muscle in the dog and with the aim of advancing in immunohistochemical and nervous characterization of this muscle, we studied the existence of subvolumes in muscle structure. We used blunt dissection in isolated muscle pieces fixed and treated with 25% nitric acid. The divisions of the sciatic nerve branches involved were used to guide the dissection. Three subvolumes were identified; one, involving the caudal head, and two in the cranial head belly; they were called caudal, proximal and distal respectively. We measured muscle fiber length, orientation, and macroscopic density to characterize these compartments. These subvolumes must be considered when muscle electromyography research is carried out, and for locomotion changes evaluation due to lesions in nerve and muscle structure of the canine pelvic limb.
Asunto(s)
Animales , Perros/anatomía & histología , Músculos Isquiosurales/anatomía & histologíaRESUMEN
In earlier studies it was found that glutamatergic transmission within the nucleus accumbens septi is involved in the performance of a learned visual shape discrimination in pigeons. This study examines what effects several kinds of glutamate and dopamine antagonists have on the same task. Pigeons were trained with the relevant discrimination, bilaterally implanted with cannulas into the nucleus accumbens and tested after various transmission blockers had been administered intracerebrally. SCH-23390, a D1 dopamine antagonist, at the dose used, had no effect, and Spiperone, a D2-dopamine and 5HT2a-serotonine antagonist, significantly decreased the error repeat trials. CNQX, a non-NMDA glutamate receptor antagonist, and Cycloleucine, an antagonist of the glycine allosteric site of NMDA receptors, had no effect. CGS-19755, a selective competitive NMDA antagonist, significantly impaired performance by significantly decreasing the percent correct trials and increasing the error repeat trials. CPPG, a II/III metabotropic glutamate antagonist, remarkably improved performance. MMPG, a III/II metabotropic glutamate antagonist, at the dose used, did not have any significant effect. The preparation employed may be a useful animal model of perceptual disturbances in schizophrenia.
Asunto(s)
Cognición/efectos de los fármacos , Antagonistas de Dopamina/farmacología , Antagonistas de Aminoácidos Excitadores/farmacología , Núcleo Accumbens/efectos de los fármacos , 6-Ciano 7-nitroquinoxalina 2,3-diona/farmacología , Alanina/análogos & derivados , Alanina/farmacología , Animales , Benzazepinas/farmacología , Columbidae , Cicloleucina/farmacología , Aprendizaje Discriminativo/efectos de los fármacos , Antagonistas de los Receptores de Dopamina D2 , Glicina/análogos & derivados , Glicina/farmacología , Núcleo Accumbens/metabolismo , Ácidos Pipecólicos/farmacología , Distribución Aleatoria , Receptor de Serotonina 5-HT2A/metabolismo , Receptores de Dopamina D1/antagonistas & inhibidores , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D2/metabolismo , Receptores de Glutamato Metabotrópico/antagonistas & inhibidores , Receptores de Glutamato Metabotrópico/metabolismo , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Receptores de N-Metil-D-Aspartato/metabolismo , Antagonistas del Receptor de Serotonina 5-HT2 , Espiperona/farmacologíaRESUMEN
1. The aim is to study some roles of the hippocampal NMDA receptor, by modifying the expression of the essential NR1 subunit, with temporal and spatial restrictions in the central nervous system (CNS) of the rat. 2. Due to their neurotropism and the size of inserts they can accomodate, herpes simplex virus type-1 (HSV-1) derived amplicon vectors were used to transfer sequences, either in sense (+) or antisense (-) orientations, of the NR1 subunit gene, or of the green fluorescent protein (GFP) gene, into the CNS. 3. Vector expression in cell lines was followed by GFP autofluorescence, immunofluorescence and western blot. 4. The vectors were inoculated into the dorsal hippocampus of adult male Wistar rats, which were evaluated for habituation to an open field, and then, for expression of the transgenes, by autofluorescence and western blot; the expression mainly happened in pyramidal cells of CA1. 5. The animals injected with vectors carrying the NR1(+) transgene showed habituation to the new environment, as also happened with rats injected with vectors carrying only the GFP transgene. 6. In contrast, animals injected with vectors carrying NR1(-) sequence, did not show habituation. This might be retrograde amnesia or disability to record the trace, suggesting that the NR1 subunit in the dorsal hippocampus, is involved in habituation to a new environment. 7. HSV-1 derived amplicon vectors appear to be useful tools to modify endogenous gene expression, at a defined period, in restricted regions of the CNS.