RESUMEN
Abstract This is the first published case report of an 11-year-old patient with a rupture of a liver hydatid cyst (HC) into the peritoneal cavity after an abdominal trauma in Iran. The disease was diagnosed using focused abdominal sonography for trauma. To date, no cases of traumatic ruptures of liver HCs in children have been reported in Iran. In the endemic regions of the world, where patients suffer from a history of trauma and constant abdominal symptoms or anaphylactic shock, early diagnosis of HC is crucial as it may disseminate to other organs. The condition needs conservative surgery and follow-up.
Asunto(s)
Humanos , Masculino , Niño , Cavidad Peritoneal/parasitología , Rotura/etiología , Equinococosis Hepática/complicaciones , Traumatismos Abdominales/complicaciones , Rotura/diagnóstico por imagen , Equinococosis Hepática/diagnóstico por imagen , IránRESUMEN
This is the first published case report of an 11-year-old patient with a rupture of a liver hydatid cyst (HC) into the peritoneal cavity after an abdominal trauma in Iran. The disease was diagnosed using focused abdominal sonography for trauma. To date, no cases of traumatic ruptures of liver HCs in children have been reported in Iran. In the endemic regions of the world, where patients suffer from a history of trauma and constant abdominal symptoms or anaphylactic shock, early diagnosis of HC is crucial as it may disseminate to other organs. The condition needs conservative surgery and follow-up.
Asunto(s)
Traumatismos Abdominales/complicaciones , Equinococosis Hepática/complicaciones , Cavidad Peritoneal/parasitología , Rotura/etiología , Niño , Equinococosis Hepática/diagnóstico por imagen , Humanos , Irán , Masculino , Rotura/diagnóstico por imagenRESUMEN
The filarial nematode Setaria bidentata was found in 10 of 31 fetuses of the red brocket deer ( Mazama americana ) from the Loreto region of the Peruvian Amazon. A total of 25 specimens were collected and morphologically identified as S. bidentata. Filarial nematodes were found in the peritoneal cavity of 9 deer fetuses and the thoracic cavity of 1 fetus. Most specimens were adult stage. In this report, we provide morphometric data for these filarial specimens. This is the first study to demonstrate prenatal S. bidentata infection in cervid fetuses. Also, the finding of S. bidentata in Peru expands the geographic range of this parasite.
Asunto(s)
Ciervos/parasitología , Enfermedades Fetales/veterinaria , Setaria (Nematodo) , Setariasis/congénito , Animales , Ciervos/embriología , Femenino , Enfermedades Fetales/parasitología , Masculino , Cavidad Peritoneal/embriología , Cavidad Peritoneal/parasitología , Perú , Setaria (Nematodo)/anatomía & histología , Setaria (Nematodo)/aislamiento & purificación , Setariasis/parasitología , Cavidad Torácica/embriología , Cavidad Torácica/parasitologíaRESUMEN
The larval stages of the cestodes Echinococcus multilocularis and Echinococcus granulosus cause the important zoonoses known as larval echinococcoses. These larvae are protected by a unique, massive, mucin-based structure known as the laminated layer. The mucin glycans of the E. granulosus laminated layer are core 1- or core 2-based O-glycans in which the core Galpß1-3 residue can initiate a chain comprising one to three additional Galpß1-3 residues, a motif not known in mammalian carbohydrates. This chain can be capped with a Galpα1-4 residue, and can be ramified with GlcNAcpß1-6 residues. These, as well as the GlcNAcpß1-6 residue in core 2, can be decorated with the Galpα1-4Galpß1-4 disaccharide. Here we extend our analysis to the laminated layer of E. multilocularis, showing that the non-decorated cores, together with Galpß1-3(Galpα1-4Galpß1-4GlcNAcpß1-6)GalNAc, comprise over 96% of the glycans in molar terms. This simple laminated layer glycome is exhibited by E. multilocularis grown either in vitro or in vivo. Interestingly, all the differences with the complex laminated layer glycome found in E. granulosus may be explained in terms of strongly reduced activity in E. multilocularis of a putative glycosyltransferase catalysing the elongation with Galpß1-3. Comparative inter-species analysis of available genomic and transcriptomic data suggested a candidate for this enzyme, amongst more than 20 putative (non-core 1) Gal/GlcNAc ß1-3 transferases present in each species as a result of a taeniid-specific gene expansion. The candidate gene was experimentally verified to be transcribed at much higher levels in the larva of E. granulosus than that of E. multilocularis.
Asunto(s)
Echinococcus granulosus/química , Echinococcus multilocularis/química , Mucinas/química , Polisacáridos/química , Animales , Cromatografía en Gel , Minería de Datos , Echinococcus granulosus/clasificación , Echinococcus granulosus/genética , Echinococcus multilocularis/clasificación , Echinococcus multilocularis/genética , Regulación Enzimológica de la Expresión Génica , Genoma , Gerbillinae , Glicosiltransferasas/genética , Glicosiltransferasas/metabolismo , Larva/química , Larva/clasificación , Espectroscopía de Resonancia Magnética , Ratones , Ratones Endogámicos BALB C , Mucinas/metabolismo , Cavidad Peritoneal/parasitología , Polisacáridos/biosíntesis , Polisacáridos/aislamiento & purificación , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Espectrometría de Masas en Tándem , TranscriptomaRESUMEN
Morphometric analysis of Schistosoma mansoni male worms obtained from AKR/J and Swiss mice was carried out. Rodents infected by the intraperitoneal route with 80 cercariae of the schistosome (LE strain) were killed by cervical dislocation at 45 and 60 days post-infection and both peritoneal lavage and perfusion of the portal system were performed for the recovery of adult worms. Characteristics including total body length, the distance between oral and ventral suckers, extension of testicular mass and the number of testes were considered in the morphological analysis. Changes that occurred in S. mansoni recovered from the peritoneal cavity or from the portal system of AKR/J and Swiss mice included total body length and reproductive characteristics. Significant morphometric alterations were also observed when worms recovered from the portal system of both strains of mice were compared with the schistosomes obtained from hamsters (Mesocricetus auratus), the vertebrate host in which the LE strain had been adapted and maintained by successive passages for more than four decades. The present results reinforce the idea that S. mansoni has high plastic potential and adaptive capacity.
Asunto(s)
Cavidad Peritoneal/parasitología , Sistema Porta/parasitología , Schistosoma mansoni/anatomía & histología , Schistosoma mansoni/fisiología , Esquistosomiasis mansoni/parasitología , Animales , Biometría , Cricetinae , Modelos Animales de Enfermedad , Masculino , Ratones , Ratones Endogámicos AKRRESUMEN
The experimental system of Taenia crassiceps cysticerci infection in BALB/c mice is considered to be the most representative model of cysticercosis. In our work, mice were sacrificed 7 and 30days after infection, and pouch fluid was collected to determine the number of accumulated cells and the concentrations of IFNγ, IL-2, IL-4, IL-6, IL-10 and nitric oxide. The injection of 50 nonbudding cysticerci into normal mouse dorsal air pouches induced a high level of IFNγ and nitric oxide production relative to the parasite load. The air pouch provides a convenient cavity that allows studying the cellular immunological aspects of the T. crassiceps parasite. The nonbudding cysticerci recovered from the air pouches contained cells that can reconstitute complete cysts in the peritoneal cavity of mice. In conclusion, these results demonstrate that the air pouch model is an alternative tool for the evaluation of the immune characteristics of T. crassiceps infection.
Asunto(s)
Modelos Animales de Enfermedad , Taenia/inmunología , Teniasis/inmunología , Animales , Cámaras de Difusión de Cultivos , Exudados y Transudados/citología , Exudados y Transudados/inmunología , Femenino , Interferón gamma/análisis , Interleucinas/análisis , Ratones , Ratones Endogámicos BALB C , Óxido Nítrico/metabolismo , Cavidad Peritoneal/parasitologíaRESUMEN
Leishmaniasis is a spectrum of infectious diseases caused by Leishmania protozoan parasites. The purpose of this study was to perform, in vitro, a comparative analysis of the activity amastigotes. Results showed excellent efficacy of all compounds against axenic amastigotes, compared to pentamidine isethionate, the reference drug used. The cytotoxic effect of these mesoionic compounds of six mesoionic compounds (three 1,3,4-thiadiazolium-2-aminide and three 1,2,3-oxadiazolium-5-olate class compounds) was evaluated in mouse peritoneal macrophages using MTT assay, low toxicity (≈ 10%) for these mammalian cells being observed. In an attempt to define a potential drug target, the activities of nitric oxide synthase (NOS) and arginase of the parasites treated with the mesoionic derivatives were evaluated. NOS was purified from a cell-free extract of infective promastigotes and axenic amastigotes and all derivatives tested were able to inhibit the enzyme as monitored by the decrease of NADPH consumption. Arginase activity from both stages of the parasite was measured using urea production and none of the compounds inhibited the enzyme activity of axenic amastigotes. However, the compounds without substituents (MI-H and SID-H) were able to inhibit arginase activity of these parasites.
Asunto(s)
Arginasa/metabolismo , Leishmania mexicana/efectos de los fármacos , Óxido Nítrico Sintasa/metabolismo , Oxadiazoles/farmacología , Tiadiazoles/farmacología , Animales , Arginasa/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Cinamatos/síntesis química , Cinamatos/química , Cinamatos/farmacología , Concentración 50 Inhibidora , Leishmania mexicana/enzimología , Leishmania mexicana/crecimiento & desarrollo , Macrófagos Peritoneales/efectos de los fármacos , Macrófagos Peritoneales/parasitología , Ratones , Ratones Endogámicos BALB C , Óxido Nítrico Sintasa/efectos de los fármacos , Oxadiazoles/síntesis química , Oxadiazoles/química , Cavidad Peritoneal/citología , Cavidad Peritoneal/parasitología , Tiadiazoles/síntesis química , Tiadiazoles/químicaRESUMEN
In an effort to develop an effective and affordable oral vaccine against porcine Taenia solium cysticercosis, the S3Pvac anti-cysticercosis vaccine was expressed in papaya calli. Taenia pisiformis experimental rabbit cysticercosis was used as a model to compare the efficacy of the oral vaccine vs. the injectable S3Pvac-synthetic and S3Pvac-phage versions. Oral S3Pvac-papaya significantly reduced the expected number of hepatic lesions and peritoneal cysticerci to a similar extent than the injectable vaccines. This study reports for the first time an effective oral vaccine against T. pisiformis cysticercosis, possibly useful against porcine T. solium cysticercosis.
Asunto(s)
Cisticercosis/prevención & control , Vacunas Antiprotozoos , Taenia/inmunología , Animales , Secuencia de Bases , Cisticercosis/patología , Cysticercus/inmunología , Femenino , Inflamación/inmunología , Inflamación/patología , Proteínas de Insectos/genética , Hígado/inmunología , Hígado/patología , Datos de Secuencia Molecular , NADH Deshidrogenasa/genética , Cavidad Peritoneal/parasitología , Cavidad Peritoneal/patología , Vacunas Antiprotozoos/administración & dosificación , Vacunas Antiprotozoos/inmunología , Conejos , Alineación de Secuencia , Taenia/genéticaRESUMEN
The present research investigated the influence of temperature and time of larvae culture on the infectivity of Strongyloides venezuelensis. Mice were infected s.c. with 1500 larvae of S. venezuelensis maintained at 28 °C for three days of culture (dc), 28 °C for seven dc or 18 °C for seven dc. On days 1, 3, 5, 7, 14 and 21 post-infection the animals were sacrificed and cell numbers in the blood, peritoneal cavity fluid (PCF), broncoalveolar fluid (BALF), cytokines, immunoglobulins, number of parasites and eggs/g of feces were quantified. Results demonstrated an increase in eosinophils and mononuclear cells in the blood, PCF and BALF of infected mice. Larvae at 28 °C/3dc induced earlier eosinophils in the PCF and BALF as opposed to larvae at 28 °C/7dc and 18 °C/7dc. Larvae at 28 °C/7dc induced higher synthesis of IL-4, IL-5 and IL-10 on days 5 and 7 post-infection. Larvae at 28 °C/3dc in culture induced higher synthesis of IL-12 than larvae of seven dc, but time in culture induced better synthesis of IFN-γ after larval migration had ceased and only adult worms were present. Larvae at 28 °C/3dc in culture induced higher synthesis of IgG and IgG1 and expelled less female parasites than larvae cultivated for seven days. In conclusion, it was observed that the infectivity of S. venezuelensis is influenced by variations in temperature and time of culture.
Asunto(s)
Strongyloides/fisiología , Estrongiloidiasis/parasitología , Animales , Anticuerpos Antihelmínticos/sangre , Recuento de Células Sanguíneas , Líquido del Lavado Bronquioalveolar/citología , Líquido del Lavado Bronquioalveolar/parasitología , Citocinas/análisis , Eosinófilos/citología , Heces/parasitología , Femenino , Inmunoglobulina G/sangre , Leucocitos Mononucleares/citología , Masculino , Ratones , Recuento de Huevos de Parásitos , Cavidad Peritoneal/citología , Cavidad Peritoneal/parasitología , Ratas , Ratas Wistar , Sigmodontinae , Strongyloides/inmunología , Temperatura , Factores de TiempoRESUMEN
Helminth infections induce strong immunoregulation that can modulate subsequent pathogenic challenges. Taenia crassiceps causes a chronic infection that induces a Th2-biased response and modulates the host cellular immune response, including reduced lymphoproliferation in response to mitogens, impaired antigen presentation and the recruitment of suppressive alternatively activated macrophages (AAMФ). In this study, we aimed to evaluate the ability of T. crassiceps to reduce the severity of experimental autoimmune encephalomyelitis (EAE). Only 50% of T. crassiceps-infected mice displayed EAE symptoms, which were significantly less severe than uninfected mice. This effect was associated with both decreased MOG-specific splenocyte proliferation and IL-17 production and limited leukocyte infiltration into the spinal cord. Infection with T. crassiceps induced an anti-inflammatory cytokine microenvironment, including decreased TNF-α production and high MOG-specific production of IL-4 and IL-10. While the mRNA expression of TNF-α and iNOS was lower in the brain of T. crassiceps-infected mice with EAE, markers for AAMФ were highly expressed. Furthermore, in these mice, there was reduced entry of CD3(+)Foxp3(-) cells into the brain. The T. crassiceps-induced immune regulation decreased EAE severity by dampening T cell activation, proliferation and migration to the CNS.
Asunto(s)
Encefalomielitis Autoinmune Experimental/inmunología , Macrófagos Peritoneales/inmunología , Linfocitos T/inmunología , Teniasis/inmunología , Animales , Encéfalo/inmunología , Encéfalo/metabolismo , Encéfalo/patología , Citocinas/sangre , Citocinas/metabolismo , Encefalomielitis Autoinmune Experimental/sangre , Encefalomielitis Autoinmune Experimental/patología , Femenino , Factores de Transcripción Forkhead/metabolismo , Expresión Génica/genética , Expresión Génica/inmunología , Glicoproteínas/inmunología , Inmunoglobulina E/sangre , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Interleucina-17/metabolismo , Activación de Linfocitos/inmunología , Activación de Macrófagos/inmunología , Macrófagos Peritoneales/metabolismo , Macrófagos Peritoneales/patología , Ratones , Ratones Endogámicos C57BL , Glicoproteína Mielina-Oligodendrócito , Fragmentos de Péptidos/inmunología , Cavidad Peritoneal/parasitología , Cavidad Peritoneal/patología , Médula Espinal/inmunología , Médula Espinal/patología , Bazo/inmunología , Bazo/patología , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Subgrupos de Linfocitos T/patología , Linfocitos T/metabolismo , Linfocitos T/patología , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Linfocitos T Reguladores/patología , Teniasis/sangre , Teniasis/parasitología , Teniasis/patología , Células Th2/inmunología , Células Th2/metabolismo , Factores de Transcripción/metabolismoRESUMEN
Hormones play a significant role in murine Taenia crassiceps cysticercosis, and they may also participate in the susceptibility to Taenia solium cysticercosis. In the present study, in vitro effects are reported for human chorionic gonadotropin (hCG) on the larval stages of T. crassiceps (WFU strain) and T. solium. Our results reveal the presence of receptors for hCG in different developmental phases of both cultured parasites. On day 30, both taeniid species had the highest percentage of receptors in the neck, strobila, and suckers, but these receptors decreased by day 60, delimiting the segments and the exterior of the developing proglottids in T. solium. At the same time, there was a large number of hCG receptors in the area of the presumptive cirrus organ and in calcareous corpuscles within the parenchyma. This is the first report detecting receptors for hCG on different larval stages of T. crassiceps and T. solium. A direct effect of hCG could be recognized by the cysticerci as a factor contributing to the growth and development of T. crassiceps and T. solium cysticerci, respectively.
Asunto(s)
Cysticercus/metabolismo , Receptores de HL/análisis , Taenia solium/metabolismo , Animales , Gonadotropina Coriónica/metabolismo , Medios de Cultivo , Cysticercus/crecimiento & desarrollo , Femenino , Técnica del Anticuerpo Fluorescente Indirecta , Humanos , Inmunohistoquímica , Ratones , Ratones Endogámicos BALB C , Cavidad Peritoneal/parasitología , Porcinos , Taenia solium/crecimiento & desarrolloRESUMEN
Previously, it has been shown that parasitic infections are able to alter the normal mammal physiology, at several extents. Thus, we investigated the effects on estrous cycle and sexual behavior induced by intraperitoneal infection with Taenia crassiceps in female host mice. Along the weeks of infection, parasites were collected from the peritoneal cavity of female mice, showing the maximum parasite load at 16 weeks. No parasites were found outside peritoneal cavity. Vaginal estrous cycle was monitored daily for 4, 8, 12 and 16 weeks of infection, and results compared against age-matched female mice. Female sexual behavior (FSB) tests were performed, one test per week. Immediately after the last behavioral test, blood was collected by cardiac puncture for steroid determinations. First of all, there was a strong tissular damage in the female reproductive tract in all infected females. The phases of the estrous cycle were interrupted at 12 and 16 weeks, with increased leukocytes and the presence of a few cornified epithelial cells and nucleated epithelial cells. The FSB decreased starting 6 weeks post infection. On the 16th week, all infected female mice ceased to exhibit sexual responses, and estradiol levels showed a significant decrease. Control mice continued showing FSB and the different phases of the estrous cycle throughout the observation period. Our results strength the notion that parasites may be considered as an evolutionary force in the reproductive ability of mammals.
Asunto(s)
Ciclo Estral , Conducta Sexual Animal , Teniasis/complicaciones , Animales , Femenino , Ratones , Ratones Endogámicos BALB C , Cavidad Peritoneal/parasitología , Esteroides/sangre , Taenia/fisiologíaRESUMEN
Type material of Litomosoides hamletti Sandground, 1934 from Glossophaga soricina soricina in Brazil and L. penai Jiménez-Quirós & Arroyo, 1960 from Carollia perspicillata azteca in Costa Rica, was examined. The morphology of the spicules shows that these species belong to the carinii group. Their synonymy with L. guiterasi Pérez Vigueras, 1934, from Artibeus jamaicensis yucatanicus in Cuba, does not appear justified because they are distinct in several characters (body length, width of female, size and shape of buccal cavity and capsule, shape of right spicule). L. hamletti is a valid species; L. penai is closely related to it and is considered to be a sub-species, L. hamletti penai Jiménez-Quirós & Arroyo, 1960. The material recovered from Glossophaga spp., previously assigned to L. guiterasi by several authors, is identified as L. h. hamletti. L. guiterasi appears to be closely related to L. chandleri Esslinger, 1973; L. chitwoodi n. sp. (= Litomosoides sp. Chitwood, 1938) seems close to these species; all three are parasites of Artibeus spp.
Asunto(s)
Quirópteros/parasitología , Filariasis/veterinaria , Filarioidea/aislamiento & purificación , Animales , Brasil , Costa Rica , Femenino , Filariasis/parasitología , Filarioidea/anatomía & histología , Filarioidea/clasificación , Masculino , Cavidad Peritoneal/parasitología , Especificidad de la EspecieRESUMEN
Twenty-five bats were trapped in Yutaje (Amazonas, Venezuela) and examined for Litomosoides (Filarioidea: Onchocercidae). Of the nine recovered bat species, only Pteronotus parnelli was infected; it is a cave-dwelling species belonging to a family, Mormoopidae, which has not previously been included in the host range of the genus. The new species, L. yutajensis n. sp., has two median cephalic bosses covered with rugosities and differs from the 15 recognized species and subspecies from bats in several characters. Alike L. molossi Esslinger, 1973, L. chandleri Esslinger, 1973 and L. chitwoodi Bain, Guerrero, Rodriguez 2003, the new species has cuticular lateral bosses on the body. Eight of 10 P. parnelli were microfilaraemic, but only three had adult worms, showing that microfilariae survive longer than adults, which could lengthen the period of transmission. No infective larvae were detected in the following macronyssid mites: 58 Ornithonyssus bacoti, Ornithonyssinae, experimentally fed on microfilaraemic bats and dissected 15 days later, and a few Radfordiella sp., Macronyssinae, recovered from P. parnelli.
Asunto(s)
Quirópteros/parasitología , Filariasis/veterinaria , Filarioidea/aislamiento & purificación , Animales , Quirópteros/clasificación , Femenino , Filariasis/parasitología , Filarioidea/anatomía & histología , Filarioidea/clasificación , Masculino , Cavidad Peritoneal/parasitología , Especificidad de la Especie , VenezuelaRESUMEN
An association between brain cysticercosis and malignant neoplasms in humans has recently been reported. To explore the possibility of a potentiating effect of cysticercosis on carcinogenesis mice infected with Taenia crassiceps cysticerci were exposed to the carcinogenic substance methyl-nitrosourea; 35% of them developed lymphoma, in contrast with 50% of control non-infected animals exposed to MNU. In this experimental model of cysticercosis we did not find a potentiating effect of peritoneal cysticercosis on the carcinogenicity of MNU.
Asunto(s)
Carcinógenos/toxicidad , Cisticercosis/fisiopatología , Linfoma/inducido químicamente , Metilnitrosourea/toxicidad , Animales , Cisticercosis/parasitología , Cysticercus/patogenicidad , Femenino , Incidencia , Linfoma/epidemiología , Ratones , Ratones Endogámicos BALB C , Cavidad Peritoneal/parasitologíaRESUMEN
Innate attack to Schistosoma mansoni cercariae was evaluated in irradiated mice. It was observed that 70% of the larvae from mice sacrificed one day after whole body irradiation with 400 or 800 rads were surrounded by cluster reactivities, without difference from controls. Differences were apparent on day 5 after irradiation with sub lethal (400 rads) or lethal doses (800 rads) suggesting that innate defence to infection take at least 5 days to be affected by low dose whole-body radiation.
Asunto(s)
Cavidad Peritoneal/parasitología , Schistosoma mansoni/efectos de la radiación , Animales , Adhesión Celular/efectos de la radiación , Rayos gamma , Inyecciones Intraperitoneales , Larva/efectos de la radiación , Macrófagos/fisiología , Macrófagos/efectos de la radiación , Masculino , Ratones , Irradiación Corporal TotalRESUMEN
Innate attack to Schistosoma mansoni cercariae was evaluated in irradiated mice. It was observed that 70 percent of the larvae from mice sacrificed one day after whole body irradiation with 400 or 800 rads were surrounded by cluster reactivities, without difference from controls. Differences were apparent on day 5 after irradiation with sub lethal (400 rads) or lethal doses (800 rads) suggesting that innate defence to infection take at least 5 days to be affected by low dose whole-body radiation
Asunto(s)
Animales , Masculino , Ratones , Adhesión Celular/efectos de la radiación , Larva/efectos de la radiación , Cavidad Peritoneal/parasitología , Schistosoma mansoni/efectos de la radiación , Rayos gamma , Inyecciones IntraperitonealesRESUMEN
Intraperitoneal inoculation of axenically cultured Entamoeba histolytica trophozoites constitutes an easy to perform, highly reproducible procedure for inducing amebic liver abscesses in hamsters. Efficiency in abscess production (95% of infected animals after 1 week) was similar to data reported using direct intrahepatic or intraportal inoculation. The morphological sequence of infection shows that amebas in the peritoneal cavity initially produce a large exudate constituted mainly of acute inflammatory cells. These cells form a rim of polymorphonuclear leukocytes surrounding the amebas, which adhere to the trophozoite and can sometimes be observed polarized to one end of the parasite, suggesting capping of surface receptors. Early stages are also characterized by the production of distant inflammatory reactions in the hepatic portal spaces. At 6 h postintraperitoneal inoculation, larger foci of inflammatory reactions surrounding amebas are developed in the peritoneum, extending to and damaging the liver surface membranes as well as the serosa of other internal organs. Thereafter, tissue damage progresses deeper into the liver parenchyma, and a few days later, coalescing granulomas and large necrotic areas are observed in the liver tissue. Based on the present morphological time-sequence study, we suggest that inflammatory cells associated with E. histolytica trophozoites play an important role in commencing the damage of liver sheaths and producing the subsequent parenchymal lesions. The simplicity and reliability of this model are important factors to consider when large numbers of experimentally induced amebic liver abscesses are needed.
Asunto(s)
Entamoeba histolytica/fisiología , Absceso Hepático Amebiano/parasitología , Hígado/parasitología , Cavidad Peritoneal/parasitología , Animales , Cricetinae , Entamoeba histolytica/patogenicidad , Entamoeba histolytica/ultraestructura , Hígado/patología , Hígado/ultraestructura , Absceso Hepático Amebiano/patología , Masculino , Mesocricetus , Microscopía Electrónica , Cavidad Peritoneal/patología , VirulenciaRESUMEN
Infections of intestinal nematodes induce the T cell-dependent proliferation of intestinal mucosal mast cells (MMC). To examine whether nematode-induced MMC proliferation is affected by the site of infestation, adult-stage nematode Nippostrongylus brasiliensis (NB) was transplanted into the normal infection site, the duodenum, or into heterotopic sites, the peritoneal cavity (i.p.) or subcutaneous tissue (s.c.), of rats. Two weeks after duodenal inoculation, MMC numbers in the small intestine had increased 6.5-fold. In contrast, i.p. and s.c. inoculation induced only slight increases of intestinal MMC. After i.p. inoculation, worm granulomas developed in the connective tissues adhering to stomach and duodenum, and large numbers of mast cells appeared around the granulomas. The majority of the latter mast cells showed histochemical features similar to MMC: they were formalin sensitive, berberine sulfate-, alcian blue+/safranine-, and rat mast cell protease (RMCP) II+. After s.c. inoculation, worm granulomas developed at the inoculation site, but the number of mast cells around the granulomas was not significantly increased. These results suggest that intense proliferation of MMC or MMC-like cells is induced only by the infections on mucosa or in mucosa-associated tissues.
Asunto(s)
Mucosa Intestinal/parasitología , Mastocitos/patología , Nippostrongylus/patogenicidad , Infecciones por Strongylida/patología , Animales , Basófilos , División Celular , Cromatografía Líquida de Alta Presión , Duodeno/parasitología , Duodeno/patología , Eosinófilos , Granuloma/patología , Inmunohistoquímica , Mucosa Intestinal/patología , Masculino , Mastocitos/inmunología , Cavidad Peritoneal/parasitología , Cavidad Peritoneal/patología , Ratas , Ratas Sprague-Dawley , Piel/parasitología , Piel/patología , Infecciones por Strongylida/sangre , VirulenciaRESUMEN
Treatment with dexamethasone (DMS) in the early phases of the experimental Schistosoma mansoni infection causes an indirect effect on the cercaria-schistosomulum transformation process. This is observed when naive albino mice are treated with that drug (50 mg/Kg, subcutaneously) and infected intraperitoneally 01 hour later with about 500 S. mansoni cercariae (LE strain). An inhibition in the host cell adhesion to the larvae, with a simultaneous delay in the cercaria-schistosomulum transformation, is observed. This effect is probably due to a blockade of the neutrophil migration to the peritoneal cavity of mice, by an impairment of the release of chemotactic substances. Such delay probably favors the killing of S. mansoni larvae, still in the transformation process, by the vertebrate host defenses, as the complement system.