Aspectos patol\uf3gicos del m\ufasculo esquel\ue9tico debido a la infecci\uf3n experimental por trypanosoma cruzi

En este estudio se muestran los signos cl\uednicos desarrollados por ratones durante la fase aguda de la infecci\uf3n producida por tres cepas de Trypanosoma cruzi. Los ratones infectados con la cepa Dm74 sufrieron alteraci\uf3n de la mobilidad de los miembros posteriores y murieron durante la fase aguda de la infecci\uf3n. El an\ue1lisis histol\uf3gico del m\ufasculo esquel\ue9tico mostr\uf3 infiltrado inflamatorio de leucocitos mononucleares y polimorfonucleares, fibroblastos, eritrocitos libres y dep\uf3sitos de IgG en el espacio intersticial del Gastrocnemius (G). La desintegraci\uf3n de las micro ti brillas y cambios en la microvasculatura, fibras nerviosas y en la uni\uf3n neuromuscular del G fueron tambi\ue9n observados. Estos resultados indican que la infecci\uf3n aguda producida por T. cruzi causa da\uf1o progresivo en la fibra muscular esquel\ue9tica y alteraci\uf3n de la actividad motora

Effects of Acute Chagasic Infection on Gestating Wistar Rats

Se investiga en ratas albinas (Rattus norvegicus), cepa Wistar, inoculadas por vía intraperitoneal con 5x10^4 tripomastigotes sanguícolas de Trypanosoma cruzi, y preñadas 10 días después de la inoculación, los efectos de la infección aguda sobre la gestación, utilizando diferentes pruebas de diagnóstico. Los resultados revelaron diferencias significativas (P < 0,01) entre los valores de parasitemia promedio de los grupos de ratas vírgenes B y ratas gestantes D, durante la primera y segunda semana de gestación, registrándose a los 12 días de la gravidez niveles de parasitemias de hasta 55 ± 3 y 27 ± 9 trips/mm³ de sangre. Anticuerpos anti-T. cruzi fueron detectados en los sueros de las ratas infectadas, mostrando diferencias significativas (P < 0,05) cuando se compara la interacción grupo-tiempo. Presencia de formas flageladas de T. cruzi en los tubos de cultivo inoculados con líquido amniótico de 3 (50%) de 6 ratas sacrificadas a término de gestación. Instauración de una miocarditis y miositis aguda de variable intensidad acompañada de nidos de amastigotes de T. cruzi a nivel del corazón, músculo esquelético y fibras musculares lisas del útero grávido. Las placentas mostraron una placentitis moderada sin parasitismo a nivel del estroma velloso, placas coriónica y desidual. Las glándulas mamarias presentaron un infiltrado celular discreto sin parasitosis en los alveólos, conductos excretores y tejido conectivo inter e intralobulillar. Las células alveolares exhibieron un citoplasma basofílico y abundante secreción. El análisis morfométrico, reveló diferencias significativas (P < 0,01) en el tamaño de fetos y placentas obtenidos de ratas infectadas D y controles sanas C. La infección chagásica aguda produjo en la rata gestante alteraciones parasitológicas, inmunológicas, histopatológicas y morfométricas importantes, las cuales fueron potenciadas por los efectos paralelos inducidos por la gravidez; la presencia de formas flageladas de T. cruzi en el líquido amniótico diagnostica la infección fetal congénita; T. cruzi no causó interrupción de la gestación y los fetos a término de la gravidez fueron aparentemente normales.506 - [email protected]@ula.veBimestralWhite Wistar rats (Rattus norvegicus) were intraperitoneally inoculated with 5x10^4 blood form trypomastigotes of Trypanosoma cruzi and impregnated 10 days after inoculation. The effects of acute infection on gestation were examined using different diagnostic tests. Results showed significant differences (P < 0.01) level in parasitemia values between group B virgin rats and group D gestating rats, during the first and second week, with levels of parasitemias 12 days after impregnation of 55 ± 3 and 27 ± 9 tryps/mm³. Anti-T. cruzi antibodies were found in the serum of infected rats, showing differences (P < 0.05) level comparing group-time interaction. Flagellate forms of T. cruzi were present in culture tubes inoculated with amniotic fluid from 3 (50%) of 6 rats sacrificed at the end of gestation. There was also myocarditis and acute myositis of varying intensity accompanied by many nest of T. cruzi amastigotes around the heart, in skeletal muscle and smooth muscle fiber in the gravid uterus. There was moderate placentitis without parasitism in the villous stroma and chorionic and decidual plates. Mammary glands showed discrete cellular infiltrate without parasitosis in the alveoli, excretory ducts and in inter and intralobular connective tissue. Alveolar cells showed basophilic cytoplasm and abundant secretion. Morphometric analysis of fetuses and placenta from infected rats D and healthy controls C showed significant differences (P < 0.01) level in size and weight. In conclusion, the gestating rats acute chagasic infection produces important parasitological, immunological, histopathological and morphometric changes: these are exacerbated by the concurrent effects of pregnancy. Flagellate forms of T. cruzi in the amniotic liquid are evidence of congenital fetal infection. T. cruzi did not interfere with gestation and at term of pregnancy the fetuses were apparently normal

Transmisión congénita de Trypanosoma cruzi en crías de ratas Wistar con infección chagásica aguda

Se evalu&oacute; la transmisi&oacute;n cong&eacute;nita de Trypanosoma cruzi en cr&iacute;as de ratas Wistar con infecci&oacute;n aguda. Las ratas fueron inyectadas intraperitonealmente con 1,5x104 tripomastigotes metac&iacute;clicos de la cepa I/PAN/VE/00/PLANALTO linaje TcI. La parasitemia fue significativamente mayor (P&lt;0,05) en las ratas infectadas pre&ntilde;adas (IP) que en las ratas infectadas v&iacute;rgenes (IV). Las cr&iacute;as de las ratas IP a los 15, 30, 45 y 60 d&iacute;as de nacidas (dn) no mostraron tripanosomas circulantes. El ensayo ELISA revel&oacute; aumento progresivo de IgM anti-T. cruzi en el suero de 6 cr&iacute;as (24%) de las ratas IP entre los 15 y 60 dn. La IgG anti-T. cruzi disminuy&oacute; progresivamente en las cr&iacute;as de ratas IP y fueron negativos a los 60 dn. Cortes de coraz&oacute;n y m&uacute;sculo esquel&eacute;tico del 15% de las cr&iacute;as con 60 dn de las ratas IP mostraron ant&iacute;geno de T. cruzi con PAP. ADN de T. cruzi fue detectado por PCR en el suero de 4 cr&iacute;as (16%) a los 60 dn de ratas IP. La presencia de anticuerpos IgM anti- T. cruzi y ADN del par&aacute;sito en las cr&iacute;as de ratas con infecci&oacute;n aguda, pueden ser considerados como un criterio de infecci&oacute;n cong&eacute;nita en las cr&iacute;as sin parasitemia patente.Congenital Trypanosoma cruzi transmission in pups of Wistar rats with acute Chagas infection Abstract: Congenital Trypanosoma cruzi transmission was evaluated in pups of Wistar rats with acute Chagas infection. The rats were injected intraperitoneally with 1.5 x 104 metacyclic tripomastigotes from the I/PAN/VE/00/PLANALTO strain TcI lineage. Parasitemia was significantly higher (P&lt;0.05) in the pregnant infected rats (PI) than in the infected virgin rats (VI). The offspring of the PI rats at 15, 30, 45 and 60 days after birth (ab) did not show circulating trypanosomes. An ELISA test revealed progressive increase of anti-T. cruzi IgM in the serum of pups (24%) of the PI rats between 15 and 60 days. Anti-T. cruzi IgM decreased progressively in the PI pups and became negative at 60 ab. Heart and skeletal muscle sections of 15% of the pups of the PI rats at 60 ab showed T. cruzi antigen with PAP. T. cruzi DNA was detected through PRC in the serum of 4 pups (16%) of PI rats at 60 ab. Presence of anti-T. cruzi IgM and parasite DNA in the pups of rats with acute infection can be considered as a criterion of congenital infection in pups without evident parasitemia

Variables associated with the post-treatment healing of lesions in patients with American cutaneous leishmaniasis in Paraná State, Brazil

The purpose of this study was to investigate the relationship of several variables to the healing of lesions in patients with American cutaneous leishmaniasis (ACL). The patients with clinical and/or laboratorial diagnoses of the disease were followed up for varying periods after treatment by clinical evaluation and indirect immunofluorescence assay (IFA), from September 2000 to December 2003. The lesions of 85.3% of the 163 patients had healed by their last return for clinical evaluation, and of these, 82.7% had negative IFA results, indicating an association between the healing of lesions and IFA negativity (p=0.000). In patients evaluated up to 120 days after treatment, there was a significant association between negative IFA results and the healing of lesions (p=0.0000). Logistic regression analysis showed that negative IFA results on patients' first return after treatment predicted a 2.175 fold greater chance of lesion healing (p=0.0001). These results indicate an association between IFA negativity at the first return up to a period of 120 days, and the healing of lesions, and that the chances of healing are significantly higher in patients with negative IFA results at their first return after treatment.<br>O objetivo deste estudo foi investigar a associação de algumas variáveis para a cicatrização de lesões em pacientes com leishmaniose tegumentar americana (LTA). Os pacientes com diagnóstico clínico e laboratorial foram acompanhados depois do tratamento por avaliação clínica e reação de imunofluorescência indireta (IFI), de setembro de 2000 a dezembro de 2003. Dos 163 pacientes 85,3% apresentaram cicatrização das lesões no último retorno para a avaliação clínica e 82,7% destes tiveram a IFI negativa indicando uma associação entre a cicatrização das lesões e a negativação da IFI (p=0,000). Nos pacientes acompanhados até 120 dias depois do tratamento houve associação significativa entre os resultados negativos da IFI e a cicatrização das lesões (p=0,0000). A análise pela regressão logística mostrou que quando a IFI do primeiro retorno após o tratamento foi negativa, o paciente tinha 2,175 mais chance de cicatrização (p=0,0001). Os resultados mostram associação entre a negativação da IFI e a cicatrização das lesões quando o primeiro retorno foi até 120 dias e que as chances de cicatrização são significativamente maiores nos pacientes que apresentaram IFI negativa no primeiro retorno depois do tratamento