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Zilton A. Andrade - One of the best experts on this subject based on the ideXlab platform.
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dynamics of capillaria Hepatica induced hepatic septal fibrosis in rats
Revista Da Sociedade Brasileira De Medicina Tropical, 2010Co-Authors: Lidiane Gaban, Márcia Maria De Souza, Cleber Douglas Lucinio Ramos, Aryon De Almeida Barbosa, Zilton A. AndradeAbstract:INTRODUCTION: The pathogenesis of septal hepatic fibrosis, induced in rats by Capillaria Hepatica infection, was studied with the aid of a large collection of stored paraffin blocks, representative of the different evolutive phases of fibrosis which appeared in 100% of infected rats. METHODS: Studies were conducted involving histology, immunohistochemistry, immunofluorescence and morphometric methods, in order to observe the dynamic behavior of the cellular and matrix components of fibrosis, over a one year period of evolution. RESULTS: Observation verified that septal fibrosis originates from several portal spaces simultaneously. Its origin and progression involve blood vessel proliferation (angiogenesis), multiplication of actin-positive cells (pericytes and myofibroblasts) and progressive collagen deposition. By the end of 4-5 months, a progressive decrease in all these components was observed, when signs of regression of septal fibrosis became more evident over time. CONCLUSIONS: Besides indicating the fundamental role played by angiogenesis in the pathogenesis of fibrosis, these morphological data concerning the dynamics of this C. Hepatica experimental model proved to be adequate for future investigations regarding the functional aspects of fibrosis induction, progression and regression.
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role of partial hepatectomy on capillaria Hepatica induced hepatic fibrosis in rats
Revista Da Sociedade Brasileira De Medicina Tropical, 2007Co-Authors: Carolina Cincura Silva Santos, Zaira Onofrenunes, Zilton A. AndradeAbstract:Sabe-se que a fibrose Hepatica pode sofrer uma reducao em sequencia uma hepatectomia parcial, uma vez que o parenquima hepatico se regenera muito rapido, mas nao o excesso de tecido fibroso. O presente trabalho avalia esta hipotese ao observar como se comporta a fibrose septal sistematizada induzida pela Capillaria Hepatica no rato, apos infeccao de 30 ou 90 dias de duracao, em animais submetidos a hepatectomia parcial. Os resultados revelaram que a fibrose em si mesma nao foi afetada na sua morfologia, mas a sua quantidade relativa apareceu diminuida significativamente no campo microscopico como consequencia do aumento da massa de tecido hepatico pos-regeneracao.
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role of partial hepatectomy on capillaria Hepatica induced hepatic fibrosis in rats
Revista Da Sociedade Brasileira De Medicina Tropical, 2007Co-Authors: Carolina Cincura Silva Santos, Zaira Onofrenunes, Zilton A. AndradeAbstract:It is known that hepatic fibrosis may regress following partial hepatectomy, since the hepatic parenchyma regenerates very rapidly, but not the excess of fibrous tissue. The present study evaluated this hypothesis by observing the behavior of systematized septal fibrosis induced by either 30 or 90-day-old Capillaria Hepatica infection, in rats subjected to partial hepatectomy. The results revealed that the morphology of the fibrosis was unaffected, but its relative quantity within the microscope field appeared significantly decreased, as a consequence of the increased liver tissue mass following regeneration.
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role of partial hepatectomy on capillaria Hepatica induced hepatic fibrosis in rats papel da hepatectomia parcial sobre a fibrose septal do figado induzida pela capillaria Hepatica em ratos
2007Co-Authors: Carolina Cincura Silva Santos, Zaira Onofrenunes, Zilton A. AndradeAbstract:It is known that hepatic fibrosis may regress following partial hepatectomy, since the hepatic parenchyma regenerates very rapidly, but not the excess of fibrous tissue. The present study evaluated this hypothesis by observing the behavior of systematized septal fibrosis induced by either 30 or 90-day-old Capillaria Hepatica infection, in rats subjected to partial hepatectomy. The results revealed that the morphology of the fibrosis was unaffected, but its relative quantity within the microscope field appeared significantly decreased, as a consequence of the increased liver tissue mass following regeneration.
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immunological tolerance to pig serum partially inhibits the formation of septal fibrosis of the liver in capillaria Hepatica infected rats
Memorias Do Instituto Oswaldo Cruz, 2004Co-Authors: Rodrigo Guimaraes Andrade, Bruna Magalhaes Gotardo, Barbara C A Assis, Jose Mengel, Zilton A. AndradeAbstract:Systhematized septal fibrosis of the liver can be induced in rats either by repeated intraperitoneal injections of pig-serum or by Capillaria Hepatica infection. The relationship between these two etiological factors, as far as hepatic fibrosis is concerned, is not known, and present investigation attempts to investigate it. C. Hepatica-induced septal fibrosis of the liver was considerably inhibited in rats previously rendered tolerant to pig-serum. Pig-serum-tolerant rats developed antibodies against pig-serum when infected with C. Hepatica, but this did not happen when the infection occurred in normal rats. On the other hand, anti-C. Hepatica antibodies failed to recognize any epitope in pig-serum, by Western blot. However, no evidence of an immunological cross reactivity was found, at least at the humoral level. Alternatively, cell-mediated mechanisms may be involved, and further investigations are warranted.
Clinton A White - One of the best experts on this subject based on the ideXlab platform.
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capillaria Hepatica pseudoinfection
American Journal of Tropical Medicine and Hygiene, 2013Co-Authors: Miguel M Cabada, Martha Lopez, Clinton A WhiteAbstract:A 54-year-old male Matsigenka native from the Manu jungle of Peru presented with the eggs shown in Figure 1. Kato Katz (Figure 2) testing revealed 1,500 eggs/g stool. The white blood cell count with differential, liver enzymes, and sputum examination were normal. No treatment was administered; however, repeated stool testing was negative. Pseudocapillariasis caused by Capillaria Hepatica was diagnosed. The transient shedding of C. Hepatica eggs (which are not usually found in the stools in hepatic capillariasis), lack of eosinophilia, and normal liver enzymes supported the diagnosis. The patient admitted eating liver of a South American Tapir (Tapirus terrestris) shortly before testing. These animals harbor unembryonated non-infective C. Hepatica eggs in the liver parenchyma.1 The unembryonated eggs reach the environment after the infected animal dies or eggs are shed in the stools of predators feeding on infected carcasses. After spending 4–8 weeks in the environment, eggs become embryonated and are able to infect the liver if ingested. Hepatic capillariasis is an uncommon human zoonotic disease distributed worldwide. It causes prolonged fever, hepatomegaly, and abdominal pain associated with eosinophilia. In contrast, C. Hepatica pseudoinfection caused by feeding on livers harboring unembryonated eggs is asymptomatic.2 Figure 1. Spontaneous rapid sedimentation test. Egg with a thick striated wall (open arrows) and flat bipolar plugs (arrow) compatible with C. Hepatica (Magnification: 400×; scale bar: 50 μm). Figure 2. Kato Katz test showing the same type of eggs (Magnification: 400×; scale bar: 50 μm).
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images in clinical tropical medicine capillaria Hepatica pseudoinfection
2013Co-Authors: Miguel M Cabada, Martha Lopez, Clinton A WhiteAbstract:A 54-year-old male Matsigenka native from the Manu jungle of Peru presented with the eggs shown in Figure 1. Kato Katz (Figure 2) testing revealed 1,500 eggs/g stool. The white blood cell count with differential, liver enzymes, and sputum examination were normal. No treatment was administered; however, repeated stool testing was negative. Pseudocapillariasis caused by Capillaria Hepatica was diagnosed. The transient shedding of C. Hepatica eggs (which are not usually found in the stools in hepatic capillariasis), lack of eosinophilia, and normal liver enzymes supported the diagnosis. The patient admitted eating liver of a South American Tapir (Tapirus terrestris) shortly before testing. These animals harbor unembryonated non-infective C. Hepatica eggs in the liver parenchyma. 1 The unembryonated eggs reach the environment after the infected animal dies or eggs are shed in the stools of predators feeding on infected carcasses. After spending 4–8 weeks in the environment, eggs become embryonated and are able to infect the liver if ingested. Hepatic capillariasis is an uncommon human zoonotic disease distributed worldwide. It causes prolonged fever, hepatomegaly, and abdominal pain associated with eosinophilia. In contrast, C. Hepatica pseudoinfection caused by feeding on livers harboring unembryonated eggs is asymptomatic. 2
Herbert Auer - One of the best experts on this subject based on the ideXlab platform.
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Capillaria Hepatica in man—an overview of hepatic capillariosis and spurious infections
Parasitology Research, 2011Co-Authors: H. -p. Fuehrer, Petra Igel, Herbert AuerAbstract:Capillaria Hepatica (syn. for Calodium hepaticum ) is a zoonotic nematode parasitizing in the livers of rodents as main hosts and in numerous other mammals including humans. It is the causative agent of the rare conditions of hepatic capillariosis and spurious C. Hepatica infections in humans. In this review, 163 reported cases of infestations with this parasite (72 reports of hepatic capillariosis, 13 serologically confirmed infestations and 78 observations of spurious infections) are summarized with an overview on the distribution, symptoms, pathology, diagnosis, serology and therapy of this rare human pathogen.
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capillaria Hepatica in man an overview of hepatic capillariosis and spurious infections
Parasitology Research, 2011Co-Authors: H. -p. Fuehrer, Petra Igel, Herbert AuerAbstract:Capillaria Hepatica (syn. for Calodium hepaticum) is a zoonotic nematode parasitizing in the livers of rodents as main hosts and in numerous other mammals including humans. It is the causative agent of the rare conditions of hepatic capillariosis and spurious C. Hepatica infections in humans. In this review, 163 reported cases of infestations with this parasite (72 reports of hepatic capillariosis, 13 serologically confirmed infestations and 78 observations of spurious infections) are summarized with an overview on the distribution, symptoms, pathology, diagnosis, serology and therapy of this rare human pathogen.
Miguel M Cabada - One of the best experts on this subject based on the ideXlab platform.
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capillaria Hepatica pseudoinfection
American Journal of Tropical Medicine and Hygiene, 2013Co-Authors: Miguel M Cabada, Martha Lopez, Clinton A WhiteAbstract:A 54-year-old male Matsigenka native from the Manu jungle of Peru presented with the eggs shown in Figure 1. Kato Katz (Figure 2) testing revealed 1,500 eggs/g stool. The white blood cell count with differential, liver enzymes, and sputum examination were normal. No treatment was administered; however, repeated stool testing was negative. Pseudocapillariasis caused by Capillaria Hepatica was diagnosed. The transient shedding of C. Hepatica eggs (which are not usually found in the stools in hepatic capillariasis), lack of eosinophilia, and normal liver enzymes supported the diagnosis. The patient admitted eating liver of a South American Tapir (Tapirus terrestris) shortly before testing. These animals harbor unembryonated non-infective C. Hepatica eggs in the liver parenchyma.1 The unembryonated eggs reach the environment after the infected animal dies or eggs are shed in the stools of predators feeding on infected carcasses. After spending 4–8 weeks in the environment, eggs become embryonated and are able to infect the liver if ingested. Hepatic capillariasis is an uncommon human zoonotic disease distributed worldwide. It causes prolonged fever, hepatomegaly, and abdominal pain associated with eosinophilia. In contrast, C. Hepatica pseudoinfection caused by feeding on livers harboring unembryonated eggs is asymptomatic.2 Figure 1. Spontaneous rapid sedimentation test. Egg with a thick striated wall (open arrows) and flat bipolar plugs (arrow) compatible with C. Hepatica (Magnification: 400×; scale bar: 50 μm). Figure 2. Kato Katz test showing the same type of eggs (Magnification: 400×; scale bar: 50 μm).
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images in clinical tropical medicine capillaria Hepatica pseudoinfection
2013Co-Authors: Miguel M Cabada, Martha Lopez, Clinton A WhiteAbstract:A 54-year-old male Matsigenka native from the Manu jungle of Peru presented with the eggs shown in Figure 1. Kato Katz (Figure 2) testing revealed 1,500 eggs/g stool. The white blood cell count with differential, liver enzymes, and sputum examination were normal. No treatment was administered; however, repeated stool testing was negative. Pseudocapillariasis caused by Capillaria Hepatica was diagnosed. The transient shedding of C. Hepatica eggs (which are not usually found in the stools in hepatic capillariasis), lack of eosinophilia, and normal liver enzymes supported the diagnosis. The patient admitted eating liver of a South American Tapir (Tapirus terrestris) shortly before testing. These animals harbor unembryonated non-infective C. Hepatica eggs in the liver parenchyma. 1 The unembryonated eggs reach the environment after the infected animal dies or eggs are shed in the stools of predators feeding on infected carcasses. After spending 4–8 weeks in the environment, eggs become embryonated and are able to infect the liver if ingested. Hepatic capillariasis is an uncommon human zoonotic disease distributed worldwide. It causes prolonged fever, hepatomegaly, and abdominal pain associated with eosinophilia. In contrast, C. Hepatica pseudoinfection caused by feeding on livers harboring unembryonated eggs is asymptomatic. 2
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doi:10.4269/ajtmh.13-0126 Copyright © 2013 by The American Society of Tropical Medicine and Hygiene Images in Clinical Tropical Medicine
2013Co-Authors: Capillaria Hepatica Pseudoinfection, Miguel M Cabada, Martha Lopez, A. ClintonAbstract:A 54-year-old male Matsigenka native from the Manu jungle of Peru presented with the eggs shown in Figure 1. Kato Katz (Figure 2) testing revealed 1,500 eggs/g stool. The white blood cell count with differential, liver enzymes, and sputum examination were normal. No treatment was admin-istered; however, repeated stool testing was negative. Pseudocapillariasis caused by Capillaria Hepatica was diag-nosed. The transient shedding of C. Hepatica eggs (which are not usually found in the stools in hepatic capillariasis), lack of eosinophilia, and normal liver enzymes supported the diag-nosis. The patient admitted eating liver of a South American Tapir (Tapirus terrestris) shortly before testing. These animals harbor unembryonated non-infective C. Hepatica eggs in the liver parenchyma.1 The unembryonated eggs reach the envi-ronment after the infected animal dies or eggs are shed in the stools of predators feeding on infected carcasses. After spend-ing 4–8 weeks in the environment, eggs become embryonated and are able to infect the liver if ingested. Hepatic capillariasis is an uncommon human zoonotic disease distributed world-wide. It causes prolonged fever, hepatomegaly, and abdominal pain associated with eosinophilia. In contrast, C. Hepatica pseudoinfection caused by feeding on livers harboring unembryonated eggs is asymptomatic.
Márcia Maria De Souza - One of the best experts on this subject based on the ideXlab platform.
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Study of the prevalence of Capillaria Hepatica in humans and rodents in an urban area of the city of Porto Velho, Rondônia, Brazil.
Instituto de Medicina Tropical de São Paulo, 2015Co-Authors: Elierson José Gomes Da ,rocha, Márcia Maria De Souza, Basano, Sérgio De Almeida, Honda, Eduardo Resende, Márcio Botelho De ,castro, Colodel, Edson Moleta, Silva, Jéssica Carolinne Damasceno E, Barros, Lauro Prado, Rodrigues, Elisa Sousa, Camargo, Luís Marcelo AranhaAbstract:Introduction: Hepatic capillariosis, caused by Capillaria Hepatica (Calodium hepaticum) (Bancroft, 1893), Travassos, 1915 (Nematoda, Trichinelloidea, Capillariidae), is a common zoonosis in rodents but is rare in humans. Seventy-two cases in humans have been reported worldwide since the first case was described by MACARTHUR in 192417,27. This study aimed to determine the prevalence of Capillaria Hepatica in humans and rodents in an urban area of Porto Velho, the capital of Rondônia, in Brazil. Methods: After conducting a census of the area, 490 residents were randomly selected, and, after signing a term of consent, provided blood samples that were screened for anti-Capillaria Hepatica antibodies. Simultaneously, rats were captured to assess the prevalence of this parasite in rodents by histopathological examination in liver sections. Results: A prevalence of 1.8% was found among residents who had specific antibodies at a dilution of 1:150, indicating exposure to parasite eggs; 0.8% of the subjects also had positive titers at a dilution of 1:400, indicating true infection. The prevalence in rats was 2%. Conclusions: The prevalence of infection with this parasite among humans and rats was low. While the prevalence encountered among humans was within the limits reported in the literature, the prevalence among rodents was much lower. KEYWORDS: Capillariasis; Capillaria Hepatica; Rondônia
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dynamics of capillaria Hepatica induced hepatic septal fibrosis in rats
Revista Da Sociedade Brasileira De Medicina Tropical, 2010Co-Authors: Lidiane Gaban, Márcia Maria De Souza, Cleber Douglas Lucinio Ramos, Aryon De Almeida Barbosa, Zilton A. AndradeAbstract:INTRODUCTION: The pathogenesis of septal hepatic fibrosis, induced in rats by Capillaria Hepatica infection, was studied with the aid of a large collection of stored paraffin blocks, representative of the different evolutive phases of fibrosis which appeared in 100% of infected rats. METHODS: Studies were conducted involving histology, immunohistochemistry, immunofluorescence and morphometric methods, in order to observe the dynamic behavior of the cellular and matrix components of fibrosis, over a one year period of evolution. RESULTS: Observation verified that septal fibrosis originates from several portal spaces simultaneously. Its origin and progression involve blood vessel proliferation (angiogenesis), multiplication of actin-positive cells (pericytes and myofibroblasts) and progressive collagen deposition. By the end of 4-5 months, a progressive decrease in all these components was observed, when signs of regression of septal fibrosis became more evident over time. CONCLUSIONS: Besides indicating the fundamental role played by angiogenesis in the pathogenesis of fibrosis, these morphological data concerning the dynamics of this C. Hepatica experimental model proved to be adequate for future investigations regarding the functional aspects of fibrosis induction, progression and regression.
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capillaria Hepatica induced hepatic fibrosis in rats paradoxical effect of repeated infections
Revista Da Sociedade Brasileira De Medicina Tropical, 2004Co-Authors: Ludmila Oliveira, Márcia Maria De Souza, Zilton A. AndradeAbstract:Multiple exposures to parasitic agents are considered an important factor in the genesis of the most severe forms of the diseases they cause. Capillaria Hepatica-induced septal fibrosis of the liver in rats usually runs without signs of portal hypertension or hepatic failure. After determining the hepatic profile of 15 animals during the course of a single infection, we submitted 20 rats to multiple Capillaria Hepatica infections to determine whether repeated exposures would augment fibrosis production, transforming septal hepatic fibrosis into a true cirrhosis. Ten single-infection rats served as controls. A total of 5 exposures, with 45-day intervals, were made. Histological changes were followed by means of surgical liver biopsies, collected prior to infection and to each re-infection. Functional changes were minimal and transient. Although a slight recrudescence of fibrosis was observed after the first two re-infections and when the single-infected control group was re-infected at the end of the experiment, subsequent re-infections failed to increase the amount of fibrosis. On the contrary, there occurred quantitative and qualitative evidence of collagen degradation and suppression of parasite development. These paradoxical results are in keeping with the hypothesis that a complex immunological modulation participates in the mechanism of hepatic fibrosis induced by Capillaria Hepatica infection in rats.
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Capillaria Hepatica-induced hepatic fibrosis in rats: paradoxical effect of repeated infections Fibrose do fígado e Capillaria Hepatica em ratos: efeito paradoxal nas infecções repetidas
2004Co-Authors: Ludmila Oliveira, Márcia Maria De Souza, Zilton De Araújo AndradeAbstract:Multiple exposures to parasitic agents are considered an important factor in the genesis of the most severe forms of the diseases they cause. Capillaria Hepatica-induced septal fibrosis of the liver in rats usually runs without signs of portal hypertension or hepatic failure. After determining the hepatic profile of 15 animals during the course of a single infection, we submitted 20 rats to multiple Capillaria Hepatica infections to determine whether repeated exposures would augment fibrosis production, transforming septal hepatic fibrosis into a true cirrhosis. Ten single-infection rats served as controls. A total of 5 exposures, with 45-day intervals, were made. Histological changes were followed by means of surgical liver biopsies, collected prior to infection and to each re-infection. Functional changes were minimal and transient. Although a slight recrudescence of fibrosis was observed after the first two re-infections and when the single-infected control group was re-infected at the end of the experiment, subsequent re-infections failed to increase the amount of fibrosis. On the contrary, there occurred quantitative and qualitative evidence of collagen degradation and suppression of parasite development. These paradoxical results are in keeping with the hypothesis that a complex immunological modulation participates in the mechanism of hepatic fibrosis induced by Capillaria Hepatica infection in rats.
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estudos sobre a fibrose septal Hepatica induzida por capillaria Hepatica patogenese e evolucao
2003Co-Authors: Márcia Maria De SouzaAbstract:Several experimental models have been used in an attempt to better understand the etiology and pathogenesis of hepatic fibrosis. Rats infected with the helminth Capillaria Hepatica regularly and rapidly develop a process of septal fibrosis that progress toward a cirrhotic morphology. Pathogenesis and fate of this fibrosis are poorly understood. The present investigation aimed at following the development of septal fibrosis, from its early formation up to to more than a year. Vascular, cellular and extracellular matrix changes were investigated by means of histological, biochemical, immunohistochemical, immunofluorescence and ultrastructural methods in 94 Wistar rats, infected with 800 embryonated eggs of C. Hepatica, and biopsied or sacrificed at different time intervals, from the 1day following infection up to one year later. At the beginning the septa exhibited different cell types, especially fibroblasts and endothelial cells. Hepatic stellate cells, myofibroblasts or demin-actin-positive cells were rare. Blood vessels appeared prominent in the septa when preparations for actin, laminin, collagen IV were examined. Six months after infection the amount of collagen diminished in the septa, which was confirmed by hydroxyprolln measurements in a statistically significant way. Vascular proliferation (angiogenesis) appeared not only as a major finding in septal formation, but also as a leading change in the infiltrating progression of the septum toward another portal space. These vascular and stromal septal changes underwent a considerable reduction by the 6'^ month of infection. However, the fibrous septa were stabilized from the 6*^ month on, blood vessels being incorporated into the new hepatic structure, which resulted from septal fibrosis. Present observations indicated that C. Hepatica-'muuced septal fibrosis, which departed from portal spaces, started around the 25th - 27th day following inoculation. Septa were predominantly composed of endothelial cells and fibroblasts plus a few a-actin cells. The early proliferation of endothelial cells and fibroblasts were accompanied by an augmented expression of TGF-p, TGF-pR and PDGF. After one year or longer, thin fibrous septa remained associated with blood vessels that had sprouted from portal spaces and were seen to conduct portal blood directly into the hepatic sinusoids. Therefore, such septal vessels seemed functionally active, which explain their persistence.