Histopathological kidney alterations in rats naturally infected with Leptospira / Alteraciones histopatológicas en ratas naturalmente infectadas con Leptospira

Introduction: Histopathological changes by Leptospira in naturally infected rodent reservoirs have been poorly described. Objective: The aim of the current study is to describe renal histopathology associated with leptospirosis infection of naturally infected rodents captured in the urban area of the city of Medellin, Colombia. Materials and methods: We performed hematoxilin-eosin (H-E) on kidney samples collected from 254 captured rodents. The positive samples were processed by Warthin Starry (W-S) staining and PCR- LipL 32. Results: Fifty one rodent kidneys showed H-E histopathological changes that consisted of inflammatory infiltrate with lympho-plasmocitary cells and histiocytes. We performed W-S staining and PCR- LipL 32 to 67 kidney samples, including the 51 that had shown detectable changes by H-E and 16 (8%) of 203 rodents with negative results. Eight of the samples that tested positive for H-E (15.7%) were also positive for W-S staining. All negative for H-E were also negative for W-S staining. Of the W-S positive samples also tested for culture only three tested positive for both. Additionally, 47 (92.1%) samples positive for H-E were positive for PCR; while eleven of the 16 (68.8%) negative for H-E were positive for PCR. The samples positive for PCR were subsequently tested for culture and 11 (23.4%) were positive. Seven samples were positive for PCR and W-S and three were positive for PCR, W-S and culture. All of the PCR- LipL 32 fragments were sequenced and showed specific amplicons for L. interrogans . Conclusions: The Leptospira infection was confirmed in all of the animals tested. The only histological kidney lesion attributable to leptospiral infection in the reservoir was interstitial nephritis.

Introducción. Los hallazgos histopatológicos ocasionados por Leptospira spp. han sido poco estudiados en poblaciones de roedores naturalmente infectados. Objetivo. Describir la histopatología renal asociada con las infecciones naturalmente adquiridas en un grupo de roedores capturados en el área urbana de Medellín, Colombia. Materiales y métodos. Se llevaron a cabo coloraciones de hematoxilina y eosina de los riñones de 254 roedores recolectados en el área de estudio. Las muestras positivas se procesaron con la coloración de Warthin-Starry y mediante reacción en cadena de la polimerasa (PCR)-LipL32. Results. Se observaron cambios histopatológicos con hematoxilina y eosina en 51 riñones de roedores, que consistieron en infiltrado inflamatorio con linfoplasmocitos e histiocitos. Se utilizó coloración de Warthin-Starry y PCR-LipL32 en 67 muestras de riñón que incluyeron las 51 muestras que tuvieron cambios detectables por hematoxilina y eosina y 16 de 203 (8 %) muestras con resultados negativos. Ocho de las muestras positivas por hematoxilina y eosina (15,7 %) también fueron positivas por la coloración de Warthin-Starry. Las muestras negativas por hematoxilina y eosina (8 %) también fueron negativas con la coloración de Warthin-Starry. Tres de las ocho muestras positivas por esta última, también lo fueron por cultivo. Además, 47 (92,1 %) muestras positivas por hematoxilina y eosina fueron positivas por PCR. Del grupo de 16 negativos por hematoxilina y eosina, 11 (68,8 %) fueron positivos por PCR. De las muestras positivas por PCR, 11 también lo fueron por cultivo (23,4 %). Siete muestras fueron positivas por PCR y Warthin-Starry y tres lo fueron por PCR, Warthin-Starry y cultivo. Todos los fragmentos de la PCR-LipL32 fueron secuenciados y mostraron secuencias específicas de L. interrogans . Conclusiones. Se confirmó la infección por Leptospira y la única lesión presente en el reservorio atribuible fue la nefritis intersticial.

Meningoencefalitis zigomicótica piogranulomatosa en un puercoespín de cola pren sil (Coendou prehensilis) / Piogranulomatous zygomycotic meningoencephalitisb in a prehensile tailed porcupine (Coendou prehensilis)

Con el término de zigomicosis (ZM) se designa un grupo de enfermedades causadas por hongos de la clase Zygomicetes, de los órdenes Mucorales y Entomophthorales, de varios géneros y especies. La presentación de ZM en animales ocurre esporádicamente en numerosas especies tanto en animales domésticos como silvestres (incluso en mamíferos marinos) y son pocos los casos comprobados de aislamiento e identificación del agente causal. Pocos hongos son considerados como neurotrópicos ya que tienden a localizarse en el SNC después de invadir el hospedador; sin embargo, la mayoría de los casos de meningitis o meningoencefalomielitis son parte de micosis sistémicas como la Candidiasis, la Criptococosis, la Aspergilosis o la ZM. El presente trabajo documenta el hallazgo de una meningoencefalitis zigomicotica secundaria a un trauma craneoencefálico en un puercoespín de cola prensil (Coendou prehensilis), siendo una enfermedad rara infrecuente en el sistema nervioso central tanto en humanos como en animales y adicionalmente sin reportes previos en esta especie.

With the word Zygomycosis (ZM) are designating a group of diseases caused by fungi of the class Zygomicetes, the orders Mucorales and Entomophthorales, of several genera and species. The presentation of ZM in animals occurs sporadically in many species both in domestic and wild animals (including marine mammals), and are checked few cases of isolation and identification of the causative agent. Few fungi are considered to be neurotropic because they tend to be located in the CNS after invading the host; however, most cases of meningitis or meningoencephalomyelitis are part of systemic fungal infection such as Candidiasis, Cryptococcosis, Aspergillosis or ZM. This paper documents the discovery of a zigomicotic meningoencephalomyelitis secondary to a head trauma in a prehensile-tailed porcupine (Coendou prehensilis), being a rare disease infrequent in the central nervous system both in human and animals and additionally without previous reports in this specie.

Angiostrongylus costaricensis: complete redescription of the migratory pathways based on experimental Sigmodon hispidus infection

Angiostrongylus costaricensis lives in the cecal and mesenteric arteries of its vertebrate hosts, and causes an inflammatory disease in humans. To investigate unknown aspects of the abdominal angiostrogyliasis pathogenesis, infected Sigmodon hispidus were sequentially studied in different times of infection. The study revealed that L3 goes alternatively through two migratory courses during its development into an adult worm: lymphatic/venous-arterial and venous portal pathways. The former is considered the principal one, because it is used by most of the larvae. Like other metastrongylides, A. costaricensis passes over the pulmonary circulation to migrate from the lymphatic system to the arterial circulation, where they circulate during some days before reaching their definitive habitat. The oviposition by mature females began on 15th day. Eggs and L1 were detected mainly in the intestine and stomach, surrounded by inflammatory reaction constituted by macrophages, monocytes, and eosinophils. They were also spread to the lungs, mesenteric lymph nodes, pancreas, spleen, and kidneys. The larvae (L1) exhibited the centripetal capacity to invade the lymphatic and venous vessels of the intestine and mesentery. Adult worms that developed in the venous intrahepatic pathway migrated downstream to reach the mesenteric veins and laid eggs that embolized in the portal hepatic vessels.

Calomys callosus: an alternative model to study fibrosis in schistosomiasis mansoni. The pathology of the acute phase

Twenty Calomys callosus, Rengger, 1830 (Rodentia-Cricetidae) were studied in the early stage of the acute schistosomal mansoni infection (42nd day). The same number of Swiss Webster mice were used as a comparative standard. Liver and intestinal sections, fixed in formalin-Millonig and embedded in paraffin, were stained with hematoxilin and eosin, PAS-Alcian Blue, pH = 1.0 and 2.5, Lennert's Giemsa, Picrosirius plus polarization microscopy, Periodic acid methanamine silver, Gomori's silver reticulin and resorcin-fuchsin. Immunohistological study (indirect immunofluorescence and peroxidase labeled extravidin-biotin methods) was done with antibodies specific to pro-collagen III, fibronectin, elastin, condroitin-sulfate, tenascin, alpha smooth muscle actin, vimentin and desmin. The hepatic granulomas were small, reaching only 27 of the volume of the hepatic Swiss Webster granuloma. They were composed mainly by large immature macrophages, often filled by schistosomal pigment, characterizing an exsudative-macrophage granuloma type. The granulomas were situated in the parenchyma and in the portal space. They were often intravascular, poor of extracellular matrix components, except fibronectin and presented, sometimes alpha smooth muscle actin and vimentin positive cells. The C. callosus intestinal granulomas were similar to Swiss Webster, showing predominance of macrophages. Therefore, the C. callosus acquire very well the Schistosoma mansoni infection, without developing strong hepatic acute granulomatous reaction, suggesting lack of histopathological signs of hypersensitivity.

Helmintos parasitos de capivaras (Hydrochaeris hydrochaeris) na sub-regiäo da Nhecolândia, Pantanal sul-mato-grossense / Helminth parasites of capybaras (Hydrochaeris hydrochaeris) on Sub-region of Nhecolândia, Pantanal, Mato Grosso do Sul

Foram realizadas 23 necropsias em capivaras (Hydrochaeris hydrochaeris) capturadas na parte central da sub-regiäo da Nhecolândia, Pantanal Sul-matogrossense, de dezembro de 1984 a dezembro de 1986. Os helmintos colhidos foram identificados e contados, resultando na seguinte lista, com suas respectivas prevalências e itensidades médias de infecçäo: Trichostrongylus axei - 60,9 e 14; Viannella hydrochoeri - 95,6 e 1031; Strongyloides chapini - 47,8 e 1014; Yatesia hydrochoerus - 44,4 e 6; Cruorifilaria tuberocauda - 40,0 e 8; Capilaria hydrochoeri - 86,9 e 156; Protozoophaga obesa - 100,0 e 7212; Taxorchis schistocotyle -56,5 e 43; Hippocrepis hippocrepis - 34,8 e 3822; Nudacotyle tertius - 8,7 e 133; Monoecocestus hydrochoeri - 54,5 e 62; e Monoecocestus hagmanni - 80,0 e 75. Desses, Y. hydrochoerus foi registrado pela primeira vez no Brasil. Por suas características e intensidades de infecçäo, C. tuberocauda, V. hydrochoeri, S. chapin e H. hippocreps podem causar parasitoses clínicas e subclínicas em capivaras na regiäo estudada. Infecçöes múltiplas ocorreram em 60,8 por cento dos estômagos, 86,8 por cento dos intestinos delgados, 66,6 por cento dos cecos e 27,7 por cento dos colos e retos. Apesar das associaçöes helmínticas predominarem, näo foram observadas interaçöes entre os helmintos parasitos do mesmo órgäo. As prevalências e abundâncias de S. chapini, Y. hydrochoerus e C. hydrochoeri foram influenciadas pela idade do hospedeiro, sendo que S. chapini apresentou valores maiores em animais jovens, enquanto os demais mostraram tendência inversa

Effects of prolactin and LH on the activity of delta5-3beta hydroxy-steroid dehydrogenase, dihydro-orotic dehydrogenase, b-hydroxybutyrate dehydrogenase and glucose-6-phosphate dehydrogenase in the testis of the dwarf mice.

The activity of delta5-3beta Hydroxysteroid hydro-genase, dihydro orotic dehydrogenase, B-Hydroxybutyrate dehydrogenase and glucose-6-phosphate dehydrogenase was studied in the testes of hereditary dwarf mice treated with Prolactin or LH. Two months old dw/dw dwarf mice were injected twice daily, for 14 days, either with 100 mug ovine Prolactin, or 5 mug ovine LH twice a day. Prolactin treatment increased the activity of all the enzymes assessed. Treatment with LH stimulated the activity of all the enzymes as compared to the saline treated animals but less than the Prolactin treated ones. The data bearing that the increased activity of several oxidising enzymes in the testes of hereditary dwarf mice is increased with Prolactin, is consistent with the suggested effect of this hormone on testicular steroidogenesis.