RESUMEN
Re-infections with Trypanosoma cruzi are an aggravating factor for Chagas disease morbidity. The Colombian strain of T. cruzi represents multiclonal populations formed by clonally propagating organisms with different tropisms and degrees of virulence. In the present study, the influence of successive inoculations with clones of the Colombian strain, exhibiting different degrees of virulence, on chronic myocarditis and the humoral and cellular immune responses (Col-C1 high virulence, Col-C8 medium virulence and Col-C5 low virulence) were demonstrated. Mice from three groups with a single infection were evaluated during the acute (14th-30th day) and chronic phases for 175 days. An immunofluorescence assay, ELISA and delayed type hypersensitivity (DTH) cutaneous test were also performed. Mice with a triple infection were studied on the 115th-175th days following first inoculation. The levels of IgM and IgG2a were higher in the animals with a triple infection. DTH showed a higher intensity in the inflammatory infiltrate based on the morphometric analysis during a 48 h period of the triple infection and at 24 h with a single infection. The histopathology of the heart demonstrated significant exacerbation of cardiac inflammatory lesions confirmed by the morphometric test. The humoral responses indicate a reaction to the triple infection, even with clones of the same strain.
Asunto(s)
Enfermedad de Chagas/parasitología , Miocarditis/parasitología , Trypanosoma cruzi/patogenicidad , Animales , Antígenos de Protozoos/inmunología , Enfermedad de Chagas/patología , Enfermedad Crónica , Clonación Molecular , Ensayo de Inmunoadsorción Enzimática , Inmunidad Celular/inmunología , Ratones , Miocarditis/patología , Parasitemia/inmunología , Trypanosoma cruzi/genética , Trypanosoma cruzi/inmunología , Virulencia/inmunologíaRESUMEN
Crotalus venom has broad biological activity, including neurotoxic, myotoxic, hematologic, and cytotoxic compounds that induce severe systemic repercussions. We evaluated the pathophysiological and clinical significance of Crotalus durissus cascavella (Cdc) venom-induced pulmonary impairment in mice. We conducted a randomized experimental study, involving 72 animals intraperitoneally inoculated with saline solution in the control group (CG), as well as venom in the experimental group (EG). The animals were euthanized at predetermined intervals (1 h, 3 h, 6 h, 12 h, 24 h, and 48 h), and lung fragments were collected for H&E and Masson histological analysis. The CG did not present inflammatory alterations in pulmonary parenchyma. In the EG, interstitial and alveolar swelling, necrosis, septal losses followed by alveolar distensions, and areas of atelectasis in the pulmonary parenchyma were observed after three hours. The EG morphometric analysis presented pulmonary inflammatory infiltrates at all time intervals, being more significant at three and six (p = 0.035) and six and 12 h (p = 0.006). The necrosis zones were significant at intervals of one and 24 h (p = 0.001), one and 48 h (p = 0.001), and three and 48 h (p = 0.035). Crotalus durissus cascavella venom induces a diffuse, heterogeneous, and acute inflammatory injury in the pulmonary parenchyma, with potential clinical implications for respiratory mechanics and gas exchange. The early recognition and prompt treatment of this condition are essential to prevent further lung injury and to improve outcomes.
Asunto(s)
Relevancia Clínica , Venenos de Crotálidos , Animales , Ratones , Venenos de Crotálidos/toxicidad , Crotalus , Modelos Animales de Enfermedad , Pulmón , NecrosisRESUMEN
This study investigated the systemic inflammatory response and mechanism of pulmonary lesions induced by Crotalus durissus cascavella venom in murine in the state of Bahia. In order to investigate T helper Th1, Th2 and Th17 lymphocyte profiles, we measured interleukin (IL) -2, IL-4, IL-6, IL-10, IL-17, tumor necrosis factor (TNF) and interferon gamma (IFN-γ) levels in the peritoneal fluid and macerated lungs of mice and histopathological alterations at the specific time windows of 1h, 3h, 6h, 12h, 24h and 48h after inoculation with Crotalus durissus cascavella venom. The data demonstrated an increase of acute-phase cytokines (IL-6 and TNF) in the first hours after inoculation, with a subsequent increase in IL-10 and IL-4, suggesting immune response modulation for the Th2 profile. The histopathological analysis showed significant morphological alterations, compatible with acute pulmonary lesions, with polymorphonuclear leukocyte (PMN) infiltration, intra-alveolar edema, congestion, hemorrhage and atelectasis. These findings advance our understanding of the dynamics of envenomation and contribute to improve clinical management and antiophidic therapy for individuals exposed to venom.
Asunto(s)
Venenos de Crotálidos/farmacología , Lesión Pulmonar/inducido químicamente , Síndrome de Respuesta Inflamatoria Sistémica/inducido químicamente , Animales , Crotalus , Citocinas/análisis , Ratones , Linfocitos T Colaboradores-Inductores/metabolismo , Factores de TiempoRESUMEN
Objetivo: o estudo visou um relato de experiências entre os autores sobre a tutoria do módulo três durante o curso EAD no ano de 2022. Método: Este curso com atividades síncronas e assíncronas, para professores da educação básica e estudantes de graduação, foi realizado em outubro e novembro, do ano de 2022 e culminou na construção de uma cartilha com mapas mentais, temas e estratégias trabalhados durante o curso comomateriais pedagógicos para o ensino fundamental II. Resultados:A cartilha intitulada: as consequências do consumo de álcool ao sistema nervoso, teve como parceria professores de duas escolas básicas. Esta apresenta informações anatomofisiológicas a respeito do funcionamento do sistema nervoso e o álcool. A temática explica como o funcionamento do sistema nervoso pode ser afetado pelo uso de bebidas alcoólicas; compreensão das alterações causadas ao funcionamento do sistema nervoso pela ingestão de álcool e instrumentalização dos professores com mais um recurso pedagógico. Conclusão:Dessa forma, foi possível a promoção da sensibilização dos estudantes quanto aos aspectos negativos do uso de bebidas alcoólicas. Assim como, prevenção nos jovens quanto ao seuuso indiscriminado, colaborando com a popularização da ciência.
Objective:the study aimed to report experiences between the authors regarding the tutoring of module three during the EAD course in the year 2022. Method:This course with synchronous and asynchronous activities, for basic education teachers and undergraduate students, was carried out in October and November, 2022 and culminated in the construction of a booklet with mental maps, themes and strategies workedon during the course as teaching materials for elementary school II. Results:The booklet entitled: the consequences of alcohol consumption on the nervous system, was partnered with teachers from two basic schools. This presents anatomophysiological information regarding the functioning of the nervous system and alcohol. The theme explains how the functioning of the nervous system can be affected by the use of alcoholic beverages; understanding the changes caused to the functioning of the nervous system byalcohol intake and providing teachers with yet another pedagogical resource. Conclusion:In this way, it was possible to promote student awareness regarding the negative aspects of the use of alcoholic beverages. As well as prevention among young people regarding its indiscriminate use, collaborating with the popularization of science.
Objetivo: el estudio tuvo como objetivo relatar experiencias entre los autores respecto a la tutoría del módulo tres durante el curso EAD en el año 2022. Método: Este curso con actividades sincrónicas y asincrónicas, para docentes de educación básica y estudiantes de pregrado, se realizó en los meses de octubre y noviembre de 2022 y culminó con la construcción de una cartilla con mapas mentales, temáticas y estrategias trabajadas durante el curso como material didáctico para la escuela primaria II. Resultados:El cuadernillo titulado: las consecuencias del consumo de alcohol en el sistema nervioso, fue elaborado en colaboración con docentes de dos escuelas básicas. Presenta información anatomofisiológica sobre el funcionamiento del sistema nervioso y el alcohol. El tema explica cómo el funcionamiento del sistema nervioso puede verse afectado por el uso de bebidas alcohólicas; comprender los cambios que provoca en el funcionamiento del sistema nervioso la ingesta de alcohol y dotar a los docentes de un recurso pedagógico más. Conclusión: De esta manera, fue posible sensibilizar a los estudiantes sobre los aspectos negativos del consumo de alcohol. Así como la prevención entre los jóvenes sobre su uso indiscriminado, contribuyendo a la popularización de la ciencia.
Asunto(s)
Educación Primaria y Secundaria , Enseñanza , Etanol , Pruebas de Inteligencia , Sistema NerviosoRESUMEN
Objetivo: estimular estudantes a serem protagonistas de ações que fomentassem na sua comunidade a popularização das ciências através de oficinas pedagógicas temáticas, colocando-os como construtores dos saberes, assim como, fortalecendo o papel extensionista da Universidade. Método:As atividades tiveram a participação de 80 alunos e foram desenvolvidas no Departamento de Ciências Biológicas (DCBIO) da Universidade Estadual de Feira de Santana (UEFS), pelos docentes do NUPEECBio, discentes e monitores. Foi realizada na SNCT (2019) com estudantes do Ensino Fundamental (6° e 7° ano) utilizando oficinas multitemáticas em Ciências. Após essa etapa, foram aplicados questionários e a avaliação qualitativa usando a Escala Likert para realizar uma avaliação qualitativa sobre a participação e adesão dos estudantes. Resultados:A análise dos dados em conjunto nos permitiu avaliar o grau de satisfação, percepção e cognição dos estudantes após cada oficina, demonstrando que as estratégias utilizadas foram exitosas. Conclusão:nessa experiência de interface Universidade e Escola básica, foi possível perceber a relevância da junção de atividades teóricas/práticas por meios de oficinas interdisciplinares no despertamento de curiosidade, motivação e receptividade dos estudantes.
Objective: to encourage students to take the lead in actions that would promote the popularization of science in their community through themed pedagogical workshops, placing them as builders of knowledge, as well as strengthening the university's extension role. Method: 80 students took part in the activities, which were carried out at the Department of Biological Sciences (DCBIO) of the State University of Feira de Santana (UEFS) by NUPEECBio teachers, students and monitors. It was held during SNCT (2019) with elementary school students (6th and 7th grade) using multi-thematic science workshops. After this stage, questionnaires and the Likert Scale were applied to carry out a qualitative assessment of student participation and adherence. Results:Analyzing the data together allowed us to assess the degree of satisfaction, perception and cognition of the students after each workshop, demonstrating that the strategies used were successful. Conclusion: in this experience of the interface between university and elementaryschool, it was possible to see the relevance of combining theoretical/practical activities through interdisciplinary workshops in arousing curiosity, motivation and receptivity in the students.
Objetivo: incentivar a los estudiantes a protagonizar acciones que promuevan la popularización de la ciencia en su comunidad a través de talleres educativos temáticos, convirtiéndolos en constructores de conocimiento y fortaleciendo el papel de extensión de la universidad. Método: 80 estudiantes participaron en las actividades, que se llevaron a cabo en el Departamento de Ciencias Biológicas (DCBIO) de la Universidad Estatal de Feira de Santana (UEFS) por profesores, estudiantes y monitores de NUPEECBio. Se llevó a cabo durante el SNCT (2019) con estudiantes de la escuela primaria (6º y 7º grado) utilizando talleres de ciencias multitemáticas. Después de esta etapa, se aplicaron cuestionarios y la Escala de Likert para llevar a cabo una evaluación cualitativa de la participación y la adhesión de los estudiantes. Resultados: El análisis conjunto de los datos nos permitió evaluar el grado de satisfacción, percepción y cognición de los alumnos luego de cada taller, demostrando que las estrategias utilizadas fueron exitosas. Conclusión: en esta experiencia de interfaz entre la universidad y la escuela primaria, fue posible constatar la importancia de la combinación de actividades teórico/prácticas a través de talleres interdisciplinares para despertar curiosidad, motivacióny receptividad en los alumnos.
Asunto(s)
Estudios InterdisciplinariosRESUMEN
OBJECTIVE:: To evaluate the effects of exposure to emissions from sugar cane burning on inflammatory mechanisms in tissues of the trachea and lung parenchyma in Wistar rats after different periods of exposure. METHODS:: This was an experimental open randomized study. The animals were divided into four groups: a control group (CG) underwent standard laboratory conditions, and three experimental groups were exposed to emissions from sugar cane burning over different periods of time, in days-1 (EG1), 7 (EG7), and 21 (EG21). After euthanasia with 200 mg/kg of ketamine/xylazine, fragments of trachea and lung were collected and fixed in 10% formalin. Histological analyses were performed with H&E and picrosirius red staining. RESULTS:: No inflammatory infiltrates were found in the tissues of CG rats. The histological examination of tissues of the trachea and lung parenchyma revealed that the inflammatory process was significantly more intense in EG7 than in the CG (p < 0.05 and p < 0.01, respectively). In comparison with the CG and EG1, angiogenesis in the lung parenchyma and collagen deposition in tracheal tissues were significantly greater only in EG21 (p < 0.001 and p < 0.01, respectively). CONCLUSIONS:: In this sample, emissions from sugar cane burning induced acute focal and diffuse inflammation in the lamina propria of tracheal tissues, with no loss of ciliated epithelial tissue. In the lung parenchyma of the animals in the experimental groups, there was interstitial and alveolar edema, together with polymorphonuclear cell infiltrates. OBJETIVO:: Avaliar os efeitos da exposição à fumaça da queima da cana-de-açúcar sobre mecanismos inflamatórios em tecidos de traqueia e de parênquima pulmonar de ratos Wistar após diferentes períodos de exposição. MÉTODOS:: Estudo experimental, randomizado, não cego. Os animais foram divididos em quatro grupos: controle (GC), sob condições padrão de laboratório e os demais expostos à fumaça da queima da cana-de-açúcar por diferentes períodos: em 1 (GE1), 7 (GE7) e 21 (GE21) dias. Após a eutanásia com 200 mg/kg de ketamina/xilazina, foram coletados fragmentos de traqueia e pulmão e fixadas em formol 10%. Análises histológicas foram realizadas com coloração com H&E e picrosírius. RESULTADOS:: Não houve infiltrado inflamatório nos tecidos no GC. O processo inflamatório na análise histológica de tecidos de traqueia e de parênquima pulmonar foi significativamente mais intenso no GE7 quando comparado ao GC (p < 0,05 e p < 0,01, respectivamente). Em comparação com os grupos GC e GE1, apenas no GE21 foi observada angiogênese significativa no parênquima pulmonar e aumento significativo de depósitos de colágeno em tecido de traqueia (p < 0,001 e p < 0,01, respectivamente). CONCLUSÕES:: Nesta amostra, a fumaça da queima de cana-de-açúcar induziu processo inflamatório focal, difuso e agudo em tecidos de traqueia na lâmina própria, sem perda do tecido epitelial ciliado. Houve presença de edemas intersticiais e alveolares e infiltrados de células polimorfonucleares no parênquima pulmonar nos animais dos grupos experimentais.
Asunto(s)
Incineración , Exposición por Inhalación/efectos adversos , Pulmón/efectos de los fármacos , Saccharum , Humo/efectos adversos , Tráquea/efectos de los fármacos , Contaminantes Atmosféricos/toxicidad , Animales , Colágeno/análisis , Pulmón/patología , Masculino , Modelos Animales , Distribución Aleatoria , Ratas Wistar , Factores de Riesgo , Factores de Tiempo , Tráquea/patologíaRESUMEN
Introdução: ainda existem muitas controvérsias sobre o binômio lúpus-gestação e, historicamente, se a gravidez for múltipla, torna-se preocupante, requerendo cuidados intensivos. Objetivo: relatar uma experiência de gravidez gemelar associada ao Lúpus Eritematoso Sistêmico. Metodologia: estudo qualitativo baseado em uma experiência gestacional utilizando-se entrevistas do tipo história oral de vida. Os relatos foram gravados, analisados e transcritos, garantindo a forma das narrativas. Resultados: a gravidez ocorreu após um ano do diagnóstico de Lúpus, ainda existindo sintomas e ainda em tratamento. O pré-natal ocorreu sem complicações. Percebeu-se nas narrativas, um estado de intensa satisfação com a gravidez, sem traços de estresse. O parto ocorreu por via vaginal, com 32 semanas, devido à ruptura de uma das bolsas amnióticas, sem intercorrências materno-fetais. Acreditamos que a prematuridade aconteceu devido aos dois fatores de riscos envolvidos na concepção: a gemelaridade e o lúpus. Conclusão: o binômio lúpus-gestação pode ter sucesso independente do tipo de gravidez (múltipla ou única). Entretanto, muitas variáveis devem ser consideradas: a atividade do Lúpus e sintomatologia na concepção, o tipo de atendimento no pré-natal e o estado emocional da gestante.
Introduction: there are still many controversies about the binomial lupus-gestation and, historically, if the pregnancy is multiple, it becomes worrying, requiring intensive care. Objective: The purpose of this study is to relate a case of twin pregnancy associated with active systemic lupus erythematosus. Methodology: qualitative research about gestational experience, supported by oral life history. Results: the woman was diagnosed one year before become pregnant, still symptomatic and in treatment. Prenatal occurred without complications and the childbirth, despite the risks of prematurity, was normal, with 32 weeks and rupture of only one amniotic sac. The other, was ruptured artificially. The time interval between twins delivery was 16 minutes, and the second twin was bigger than the first. Historically, a twin pregnancy in association of Lupus is very worrying and requires intensive care. However, according to the narratives, the symptoms of the disease have simply disappeared and the joy of being a mother, prevail over the disease. We believe that prematurity occurred due to the two risk factors involved in the conception: gemelarity and Lupus. Conclusion: The Binomial lupus-gestation can succeed independently of the type of pregnancy (multiple or single). However, many variables should be considered: the activity of Lupus and symptomatology in conception, the type of prenatal care and the emotional state of the pregnant woman.
Asunto(s)
Humanos , Femenino , Embarazo Gemelar , Lupus Eritematoso SistémicoRESUMEN
ABSTRACT Objective: To evaluate the effects of exposure to emissions from sugar cane burning on inflammatory mechanisms in tissues of the trachea and lung parenchyma in Wistar rats after different periods of exposure. Methods: This was an experimental open randomized study. The animals were divided into four groups: a control group (CG) underwent standard laboratory conditions, and three experimental groups were exposed to emissions from sugar cane burning over different periods of time, in days-1 (EG1), 7 (EG7), and 21 (EG21). After euthanasia with 200 mg/kg of ketamine/xylazine, fragments of trachea and lung were collected and fixed in 10% formalin. Histological analyses were performed with H&E and picrosirius red staining. Results: No inflammatory infiltrates were found in the tissues of CG rats. The histological examination of tissues of the trachea and lung parenchyma revealed that the inflammatory process was significantly more intense in EG7 than in the CG (p < 0.05 and p < 0.01, respectively). In comparison with the CG and EG1, angiogenesis in the lung parenchyma and collagen deposition in tracheal tissues were significantly greater only in EG21 (p < 0.001 and p < 0.01, respectively). Conclusions: In this sample, emissions from sugar cane burning induced acute focal and diffuse inflammation in the lamina propria of tracheal tissues, with no loss of ciliated epithelial tissue. In the lung parenchyma of the animals in the experimental groups, there was interstitial and alveolar edema, together with polymorphonuclear cell infiltrates.
RESUMO Objetivo: Avaliar os efeitos da exposição à fumaça da queima da cana-de-açúcar sobre mecanismos inflamatórios em tecidos de traqueia e de parênquima pulmonar de ratos Wistar após diferentes períodos de exposição. Métodos: Estudo experimental, randomizado, não cego. Os animais foram divididos em quatro grupos: controle (GC), sob condições padrão de laboratório e os demais expostos à fumaça da queima da cana-de-açúcar por diferentes períodos: em 1 (GE1), 7 (GE7) e 21 (GE21) dias. Após a eutanásia com 200 mg/kg de ketamina/xilazina, foram coletados fragmentos de traqueia e pulmão e fixadas em formol 10%. Análises histológicas foram realizadas com coloração com H&E e picrosírius. Resultados: Não houve infiltrado inflamatório nos tecidos no GC. O processo inflamatório na análise histológica de tecidos de traqueia e de parênquima pulmonar foi significativamente mais intenso no GE7 quando comparado ao GC (p < 0,05 e p < 0,01, respectivamente). Em comparação com os grupos GC e GE1, apenas no GE21 foi observada angiogênese significativa no parênquima pulmonar e aumento significativo de depósitos de colágeno em tecido de traqueia (p < 0,001 e p < 0,01, respectivamente). Conclusões: Nesta amostra, a fumaça da queima de cana-de-açúcar induziu processo inflamatório focal, difuso e agudo em tecidos de traqueia na lâmina própria, sem perda do tecido epitelial ciliado. Houve presença de edemas intersticiais e alveolares e infiltrados de células polimorfonucleares no parênquima pulmonar nos animais dos grupos experimentais.
Asunto(s)
Animales , Masculino , Incineración , Exposición por Inhalación/efectos adversos , Pulmón/efectos de los fármacos , Saccharum , Humo/efectos adversos , Tráquea/efectos de los fármacos , Contaminantes Atmosféricos/toxicidad , Colágeno/análisis , Pulmón/patología , Modelos Animales , Distribución Aleatoria , Ratas Wistar , Factores de Riesgo , Factores de Tiempo , Tráquea/patologíaRESUMEN
Re-infections with Trypanosoma cruzi are an aggravating factor for Chagas disease morbidity. The Colombian strain of T. cruzi represents multiclonal populations formed by clonally propagating organisms with different tropisms and degrees of virulence. In the present study, the influence of successive inoculations with clones of the Colombian strain, exhibiting different degrees of virulence, on chronic myocarditis and the humoral and cellular immune responses (Col-C1 high virulence, Col-C8 medium virulence and Col-C5 low virulence) were demonstrated. Mice from three groups with a single infection were evaluated during the acute (14th-30th day) and chronic phases for 175 days. An immunofluorescence assay, ELISA and delayed type hypersensitivity (DTH) cutaneous test were also performed. Mice with a triple infection were studied on the 115th-175th days following first inoculation. The levels of IgM and IgG2a were higher in the animals with a triple infection. DTH showed a higher intensity in the inflammatory infiltrate based on the morphometric analysis during a 48 h period of the triple infection and at 24 h with a single infection. The histopathology of the heart demonstrated significant exacerbation of cardiac inflammatory lesions confirmed by the morphometric test. The humoral responses indicate a reaction to the triple infection, even with clones of the same strain.
Asunto(s)
Animales , Ratones , Enfermedad de Chagas/parasitología , Miocarditis/parasitología , Trypanosoma cruzi/patogenicidad , Antígenos de Protozoos/inmunología , Enfermedad Crónica , Clonación Molecular , Enfermedad de Chagas/patología , Ensayo de Inmunoadsorción Enzimática , Inmunidad Celular/inmunología , Miocarditis/patología , Parasitemia/inmunología , Trypanosoma cruzi/genética , Trypanosoma cruzi/inmunología , Virulencia/inmunologíaRESUMEN
A infecção pelo Trypanosoma cruzi determina uma resposta imunológica inata do hospedeiro vertebrado, decorrente da multiplicação parasitaria em macrófagos e a produção de Interferon gama (IFNy) pelas células T ativadas, além de estimulação policlonal de células do baço, com imunossupressão. Por outro lado tem sido demonstrado que o tratamento com quimioterápico Benzonidazol em camundongos infectados, além de determinar uma destruição dos parasitos, tem também uma ação sobre o sistema imunológico em camundongos infectados com cepas do T. cruzi com diferentes graus de suscetibilidade ao Benzonidazol, como a cepa Y (suscetível ao quimioterápico) e a cepa Colombiana (resistente). No presente estudo procura-se investigar a influência do tratamento com o Benzonidazol sobre a resposta imunológica em camundongos infectados com cepa suscetível (Cepa Y) ou resistente (Colombiana). Foram utilizados 320 camundongos, subdivididos em grupos experimentais: Infectados tratados cepa Y (YT) e não tratados (Y-NT); Colombiana tratados (COL-T) e não tratados (COL-NT), Tratados não infectados (TNI) e Controles sem tratamento (CI). O inóculo foi de 1,0 x 104 por via intraperitoneal. O tratamento foi iniciado no pico parasitêmico de cada cepa, sendo no 7º dia após a infecção nos animais infectados pela cepa Y e, nos tratados e não infectados, no 18º dia de infecção na cepa Colombiana. A quimioterapia foi realizada em 60 doses (100mg/kg/dia de Benzonidazol-Benz). Os camundongos sacrificados na fase aguda e na fase crônica em todos os grupos tiveram as secções de coração e músculo esquelético coletadas, fixadas e processadas para o estudo histopatológico em secções coradas pela Hematoxilina & Eosina e Picro-Sirius. Investigou-se a resposta humoral pela sorologia (Imunofluorescência indireta) e pela reação de Elisa. A resposta celular pela proliferação celular do baço, e pela avaliação quantitativa das subpopulações celulares no baço de CD4+, CD8+...
Infection with T. cruzi determines an immunological response in the vertebrate host, wit h parasites multiplication in macrophages, with production of TNFα by these cells an IFNγ, by stimulated T. cells: a polyclonal multiplication of spleen cells is present, with immunossuppression. Treatment of infected mice with BENZ showed that this chemotherapy determines parasitic destruction and also stimulates the immunological system in mice infected either with the Y or the Colombian strain which differs in the susceptibility to chemotherapy with BENZ. In the present study we intend to investigate the influence of treatment with BENZ on the immunological response in mice infected either with the Y strain (susceptible) or the Colombian strain (resistant). This study was performed by comparing the results obtained with the groups of mice not infected and treated, and infected controls, not treated. Material and methods : Number of animals: 320, sub-divided in the experimental groups:Ystrain infected and treated with BENZ(YT) or not-treated (YNT); Colombian treated (COL-T) and not-treated (COL-NT); treated not infected (TNI); Control not treated (COL-NT). Inoculum : 1x104 trypomastigotes, (blood forms) injected intraperitoneally. Treatment was initiated in the peak of parasitemia for each strain:7th day for the Y strain and in the 18th day in the infection with the Colombian strain. Chemotherapy was performed in 60 doses (100mg x kg x day) of BENZ. Mice were killed in the acute and chronic phases post infection; sections of the heart and skeletal muscles were collected, fixed and processed for histopathology, in sections stained with Hematoxylin and Eosin, and with Picro-Sirius staining, for collagen. The humoral response was evaluated by serological reactium of indirect immununofluorescence and ELISA reaction. Celular responses were evaluated by celular proliferation in the spleen of CD4+, CD8+...