RESUMEN
The spatiotemporal population dynamics of Lutzomyia longipalpis (Lutz & Neiva, 1912) (Diptera: Psychodidae) were evaluated in a city in Argentina in which visceral leishmaniasis is endemic. Over 14 sampling sessions, 5244 specimens of five species of Phlebotominae (Diptera: Psychodidae) were captured, of which 2458 (46.87%) specimens were L. longipalpis. Generalized linear models were constructed to evaluate the associations between L. longipalpis abundance and explanatory variables derived from satellite images. The spatial variable 'stratum' and the temporal variable 'season' were also included in the models. Three variables were found to have significant associations: the normalized difference vegetation index; land surface temperature, and low urban coverage. The last two of these were associated with L. longipalpis abundance only during summer and winter, respectively. This variation between seasons supports the development of models that include temporal variables because models of distributions of the abundance of a species may show different critical variables according to the climatic period of the year. Abundance decreased gradually towards the downtown area, which suggests that L. longipalpis responds to a meta-population structure, in which rural-periurban source populations that persist over time may colonize adjacent areas. This information allows for a spatiotemporal stratification of risk, which provides public health authorities with a valuable tool to help optimize prevention measures against visceral leishmaniasis.
Asunto(s)
Distribución Animal , Ecosistema , Insectos Vectores/fisiología , Psychodidae/fisiología , Animales , Argentina , Ciudades , Femenino , Masculino , Dinámica Poblacional , Estaciones del Año , Nave Espacial , Análisis Espacio-TemporalRESUMEN
Chlamydia psittaci was detected in 152 (72%) blue-fronted Amazon parrots (Amazona aestiva, parrot from the Psittacidae family) out of a population of 212 that died during 2009-2011 in a wildlife rescue and rehabilitation centre in Minas Gerais, Brazil, following rescue from illegal wildlife trafficking. The macroscopic changes observed in these animals were hepatomegaly with multifocal white foci visible at the serosal surfaces of the liver, and extending into the parenchyma, and splenomegaly. The microscopic lesions observed in the liver included multifocal to coalescing miliary necrosis of hepatocytes with infiltration by heterophils, lymphocytes and plasma cells. In the spleen, loss of the normal architecture and infiltration by macrophages and plasma cells were observed. Stained tissue sections (Gimenez technique) revealed small round clusters suggestive of C. psittaci (reticulate bodies) in the cytoplasm of macrophages from the liver and spleen. Nine sequences of segments of the ompA gene, obtained from different individuals, were randomly selected for sequencing. The phylogenetic analyses showed that all strains clustered with genotype A, which is the most virulent genotype for birds. This genotype is involved in mortality of psittacines, is easily transmitted in captivity and represents a problem for successful rehabilitation. The results indicate the necessity to improve biosecurity in triage and to provide individual personal protection for professionals and caretakers.
Chlamydia psittaci a été détectée chez 152 (72 %) amazones à front bleu (Amazona aestiva, perroquet de la famille des Psittacidés) sur un total de 212 individus rescapés du trafic illégal et décédés en 2009 et 2011 dans un centre de sauvetage et de réhabilitation de la faune sauvage à Minas Gerais (Brésil). Les modifications macroscopiques observées sur ces oiseaux étaient une hépatomégalie avec des foyers blancs multifocaux visibles sur les surfaces séreuses du foie et s'étendant dans le parenchyme, et une splénomégalie. Les lésions microscopiques observées dans le foie comprenaient une nécrose miliaire multifocale à coalescente des hépatocytes avec infiltration d'hétérophiles, de lymphocytes et de plasmocytes. Dans la rate, une perte de l'architecture normale et l'infiltration de macrophages et de plasmocytes ont été observées. La coloration de coupes de tissus (technique de Gimenez) a révélé de petites grappes rondes évoquant C. psittaci (corps réticulés) dans le cytoplasme des macrophages du foie et de la rate. Neuf produits segmentés d'une partie du gène ompA, obtenus de différents individus, ont été sélectionnés de manière aléatoire pour le séquençage. Les analyses phylogénétiques ont montré que toutes les souches se regroupaient dans le génotype A, qui est le plus virulent pour les oiseaux. Ce génotype est responsable de cas de mortalité chez les psittacidés et se transmet facilement en captivité, ce qui représente un risque pour la réussite des opérations de réhabilitation. Au vu de ces résultats, les auteurs soulignent la nécessité d'améliorer la biosécurité lors du tri des animaux dans les centres de soins et de fournir une protection individuelle aux professionnels et aux gardiens.
Se detectó Chlamydia psittaci en 152 (72%) amazonas frentiazules (Amazona aestiva, loro de la familia Psittacidae) de un total de 212 que murieron durante 20092011 en un centro de rescate y rehabilitación de fauna silvestre de Minas Gerais, Brasil, tras haber sido rescatadas del tráfico ilegal. Los cambios macroscópicos que se observaron en estos animales fueron hepatomegalia con focos blancos multifocales visibles en las superficies serosas del hígado y que se extendían hacia el parénquima, y esplenomegalia. Las lesiones microscópicas observadas en el hígado consistieron en necrosis miliar multifocal a coalescente de hepatocitos con infiltración de heterófilos, linfocitos y células plasmáticas. En el bazo, se observó pérdida de la arquitectura normal y infiltración de macrófagos y células plasmáticas. Cortes de tejido teñidos (con la técnica de Giménez) revelaron pequeños racimos redondos que sugerían la presencia de C. psittaci (cuerpos reticulados) en el citoplasma de macrófagos del hígado y del bazo. A partir de distintos individuos, se escogieron aleatoriamente nueve segmentos del gen ompA para ser secuenciados. Los análisis filogenéticos mostraron que todas las cepas correspondían al genotipo A, que es el más virulento para las aves. Este genotipo está involucrado en la mortalidad de psitácidas, se transmite fácilmente en cautiverio y supone un riesgo para el éxito de la rehabilitación. Los resultados indican la necesidad de mejorar la bioseguridad en el triaje y de procurar protección personal individual a profesionales y cuidadores.
Asunto(s)
Amazona/microbiología , Proteínas de la Membrana Bacteriana Externa/genética , Enfermedades de las Aves/microbiología , Chlamydophila psittaci/genética , Hepatopatías/veterinaria , Filogenia , Animales , Brasil , Hepatopatías/microbiologíaRESUMEN
During three decades, an enormous number of studies have demonstrated the critical role of nitric oxide (NO) as a second messenger engaged in the activation of many systems including vascular smooth muscle relaxation. The underlying cellular mechanisms involved in vasodilatation are essentially due to soluble guanylyl-cyclase (sGC) modulation in the cytoplasm of vascular smooth cells. sGC activation culminates in cyclic GMP (cGMP) production, which in turn leads to protein kinase G (PKG) activation. NO binds to the sGC heme moiety, thereby activating this enzyme. Activation of the NO-sGC-cGMP-PKG pathway entails Ca2+ signaling reduction and vasodilatation. Endothelium dysfunction leads to decreased production or bioavailability of endogenous NO that could contribute to vascular diseases. Nitrosyl ruthenium complexes have been studied as a new class of NO donors with potential therapeutic use in order to supply the NO deficiency. In this context, this article shall provide a brief review of the effects exerted by the NO that is enzymatically produced via endothelial NO-synthase (eNOS) activation and by the NO released from NO donor compounds in the vascular smooth muscle cells on both conduit and resistance arteries, as well as veins. In addition, the involvement of the nitrite molecule as an endogenous NO reservoir engaged in vasodilatation will be described.
Asunto(s)
Animales , Humanos , Ratas , Células Endoteliales/metabolismo , Donantes de Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo III/metabolismo , Óxido Nítrico/biosíntesis , Compuestos de Rutenio/metabolismo , Endotelio Vascular/metabolismo , Hipertensión/fisiopatología , Músculo Liso Vascular/metabolismo , Óxido Nítrico/farmacología , Vasodilatación/fisiologíaRESUMEN
During three decades, an enormous number of studies have demonstrated the critical role of nitric oxide (NO) as a second messenger engaged in the activation of many systems including vascular smooth muscle relaxation. The underlying cellular mechanisms involved in vasodilatation are essentially due to soluble guanylyl-cyclase (sGC) modulation in the cytoplasm of vascular smooth cells. sGC activation culminates in cyclic GMP (cGMP) production, which in turn leads to protein kinase G (PKG) activation. NO binds to the sGC heme moiety, thereby activating this enzyme. Activation of the NO-sGC-cGMP-PKG pathway entails Ca(2+) signaling reduction and vasodilatation. Endothelium dysfunction leads to decreased production or bioavailability of endogenous NO that could contribute to vascular diseases. Nitrosyl ruthenium complexes have been studied as a new class of NO donors with potential therapeutic use in order to supply the NO deficiency. In this context, this article shall provide a brief review of the effects exerted by the NO that is enzymatically produced via endothelial NO-synthase (eNOS) activation and by the NO released from NO donor compounds in the vascular smooth muscle cells on both conduit and resistance arteries, as well as veins. In addition, the involvement of the nitrite molecule as an endogenous NO reservoir engaged in vasodilatation will be described.
Asunto(s)
Células Endoteliales/metabolismo , Donantes de Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo III/metabolismo , Óxido Nítrico/biosíntesis , Compuestos de Rutenio/metabolismo , Animales , Endotelio Vascular/metabolismo , Humanos , Hipertensión/fisiopatología , Músculo Liso Vascular/metabolismo , Óxido Nítrico/farmacología , Ratas , Vasodilatación/fisiologíaRESUMEN
O objetivo do trabalho foi avaliar a qualidade fisiológica e sanitária das sementes obtidas a partir de frutos maduros coletados no solo e nas plantas de fava d'anta, espécie medicinal nativa do Cerrado, ameaçada de extinção, cujos frutos são ricos em rutina. O delineamento experimental empregado foi o inteiramente casualizado, com 10 repetições. Cada repetição foi constituída de uma caixa gerbox contendo 15 sementes cada. A qualidade fisiológica foi determinada por meio de testes de germinação e vigor, avaliando-se a porcentagem de germinação, o índice de velocidade de germinação (IVG) e a massa seca das raízes primárias. A qualidade sanitária foi determinada pela identificação dos microorganismos patogênicos associados às sementes, bem como pela porcentagem de ocorrência destes em cada parcela. Os fungos identificados nas sementes pertencem aos gêneros Fusarium, Alternaria, Aspergillus, Cladosporium, Colletrotrichum, Helminthosporium, Nigrospora, Penicillum, Phoma e Phomopsis. Sementes oriundas de frutos coletados no solo foram mais contaminadas por agentes patogênicos e apresentaram germinação (56,67 por cento), vigor e sanidade inferiores às sementes obtidas de frutos coletados na planta.
The aim of this work was to evaluate the physiological and sanitary quality of seeds obtained from mature fruits collected in the soil and in "fava d'anta" plants. Dimorphandra mollis constitutes an endangered medicinal species native to cerrado and presents fruits rich in rutin. The experimental design was completely randomized, with 10 replicates. Each replicate consisted of a gerbox containing 15 seeds each. Physiological quality was assessed through germination and vigor tests by evaluating germination percentage, germination velocity index (GVI), and primary root dry matter. Sanitary quality was evaluated by identifying pathogenic microorganisms associated with the seeds, as well as their occurrence percentage in each plot. The identified fungi belonged to the genera Fusarium, Alternaria, Aspergillus, Cladosporium, Colletotrichum, Helminthosporium, Nigrospora, Penicillium, Phoma and Phomopsis. Seeds from fruits collected in the soil were more contaminated by pathogenic agents and presented lower germination (56.67 percent), vigor and health than seeds from fruits collected in the plant.
Asunto(s)
Germinación/fisiología , Vicia faba/fisiología , Frutas/fisiología , Plantas Medicinales/clasificación , Cladosporium/clasificación , Fusarium/clasificaciónRESUMEN
Carapa guianensis (Meliaceae), known as Andiroba in Brazil, has been used by Amazon Rainforest indigenous communities for treatment of coughs, convulsions, skin diseases, arthritis, rheumatism, ear infections, to heal wounds and bruises and as an insect repellent. Carapa guianensis seed oil (SO) was evaluated for its acute and subacute toxicity (30 days) by the oral route in Wistar rats. In the acute toxicity test, SO (0.625-5.0g/kg, n=5/sex) did not produce any hazardous symptoms or deaths. The subacute treatment with SO (0.375, 0.75 and 1.5g/kg, n=10/group) failed to change body weight gain, food and water consumption. Hematological analysis showed no significant differences in any of the parameters examined. However, in the biochemical parameters, there was an increase in the alanine aminotransferase (ALT) serum level (29%) in the group SO 1.5g/kg. In addition, absolute and relative liver weights were increased at the doses of 0.75g/kg (23.4 and 19.1%) and 1.5g/kg (18.7 and 33.1%). In conclusion, acute and subacute administration of Carapa guianensis seed oil did not produce toxic effects in male Wistar rats. However, the increase in the ALT serum level and in both absolute and relative liver weights may indicate a possible hepatic toxicity.
Asunto(s)
Meliaceae/química , Tamaño de los Órganos/efectos de los fármacos , Extractos Vegetales/toxicidad , Animales , Análisis Químico de la Sangre , Peso Corporal/efectos de los fármacos , Ingestión de Líquidos/efectos de los fármacos , Ingestión de Alimentos/efectos de los fármacos , Femenino , Masculino , Aceites de Plantas/química , Aceites de Plantas/toxicidad , Ratas , Ratas Wistar , Factores de Tiempo , Pruebas de Toxicidad AgudaRESUMEN
The effects of the administration of Carapa guianensis Aublet (Meliaceae) seed oil were investigated during pregnancy in female Wistar rats. Five groups of pregnant rats (n=5-9 per group) were treated orally from the 7th to the 14th day of pregnancy (organogenic period), at doses of: 0, 0.375, 0.75, 1.5 and 3.0gkg(-1). On the 20th day of pregnancy, the animals were sacrificed and laparotomized to evaluate reproductive parameters. The results showed that there was no difference between the control and treated groups in terms of the number of live and dead fetuses, the dam-offspring relationship, the weight of the fetus, the weight of the placentae and ovaries, the number of implantation sites, the number of resorption sites, the number of corpora lutea in the ovaries, and the pre- and post-implantation loss rates. It is therefore concluded that administration of Carapa guianensis seed oil did not bring about any toxic effect on pregnancy in Wistar rats.