Nociceptive and histomorphometric evaluation of the effects of ozone therapy on the rat masseter muscle in a carrageenan model of myofascial pain.

OBJECTIVE: This study evaluated the effects of intramuscular ozone therapy on nociception, inflammation, and tissue damage caused by the injection of carrageenan in the masseter muscle of rats. DESIGN: Rat masseter muscles were injected with saline or carrageenan. Seventy-seven adult male rats were divided into six groups: Sal, saline; Car, carrageenan; Ibup + Sal, ibuprofen and saline; Ibup + Car, ibuprofen and carrageenan; O3 + Sal, ozone and saline; and O3 + Car, ozone and carrageenan. The mixture of 5% ozone and 95% oxygen (20 µg/mL) was administered three times in the course of a week. Nociceptive responses in the masseter muscles were measured using a head withdrawal threshold, determined by an electronic von Frey anesthesiometer. The animals were euthanized one or eight days after the carrageenan injection, and the masseters were submitted to histological and histomorphometric analyses. RESULTS: Mechanical allodynia and inflammation levels were reduced in the Ibup + Car group compared to the other groups. Myonecrosis was similar among carrageenan-treated groups. Picrosirius red stained sections showed more collagen fibers and more regenerating myofibers in the O3 + Car group compared to the other groups. Eight days after carrageenan injection, the O3 + Car group showed neutrophils close to the regenerating myofibers. CONCLUSIONS: Intramuscular ozone therapy did not alleviate mechanical allodynia, and it did not protect the masseter muscle against the deleterious effects produced by carrageenan, probably due to the mode of administration of this therapeutic agent.

O ensino de ciências na educação básica: desvendando o sistema nervoso através de cartilhas e mapas mentais / Science teaching in basic education: unveiling the nervous system through primers and mental maps / Enseñanza de ciencias en educación básica: desvelando el sistema nervioso a través de primers y mapas mentales

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.

Oficinas multitemáticas: Estudantes como protagonistas na popularização da ciência em Feira de Santana -BA / Multi-thematic workshops: Students as protagonists in the popularization of science in Feira de Santana -BA / Talleresmultitemáticos: los estudiantes como protagonistas de la divulgación científica en Feira de Santana ­BA

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.

Pathophysiological and Clinical Significance of Crotalus durissus cascavella Venom-Induced Pulmonary Impairment in a Murine Model.

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.

Bothrops leucurus snake venom protein profile, isolation and biological characterization of its major toxin PLA2s-like.

Bothrops leucurus is considered as a snake of medical interest in the State of Bahia, Brazil. However, so far, there are no studies that provide a refined mapping of the composition of this venom. The aim of this work was to better understand the protein composition of B. leucurus snake venom and to isolate and biologically characterize the most abundant toxin, a basic PLA2-like. Shotgun proteomics approach identified 137 protein hits in B. leucurus venom subdivided into 19 protein families. The new basic PLA2-like toxin identified was denominated Bleu-PLA2-like, it and other proteoforms represents about 25% of the total proteins in the venom of B. leucurus and induces myotoxicity, inflammation and muscle damage. Immunoreactivity assays demonstrated that B. leucurus venom is moderately recognized by bothropic and crotalic antivenoms, and on the other hand, Bleu-PLA2-like and its proteoforms are poorly recognized. Our findings open doors for future studies in order to assess the systemic effects caused by this snake venom in order to better understand the toxinological implications of this envenomation and, consequently, to assist in the clinical treatment of victims.

Vivência de gestação gemelar associada a Lúpus Eritematoso Sistêmico-LES / Experience of twin pregnancy associated with Systemic Lupus Erythematosus-SLE

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.

Evaluation of systemic inflammatory response and lung injury induced by Crotalus durissus cascavella venom.

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.

Effects of emissions from sugar cane burning on the trachea and lungs of Wistar rats.

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.

Effects of emissions from sugar cane burning on the trachea and lungs of Wistar rats / Efeitos das emissões geradas pela queima da cana-de-açúcar em traqueia e pulmões de ratos Wistar

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.

Immunological response to re-infections with clones of the Colombian strain of Trypanosoma cruzi with different degrees of virulence: influence on pathological features during chronic infection in mice

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.

Immunological response to re-infections with clones of the Colombian strain of Trypanosoma cruzi with different degrees of virulence: influence on pathological features during chronic infection in mice.

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.

Influência do tratamento com benzonidazol na resposta imunológica de camundongos infectados com cepas do trypanosoma cruzi de diferentes biodemas / Influence of treatment with benznidazole in the immune response of mice infected with Trypanosoma cruzi strains of different biodemes

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+...

Effect of treatment with cyclophosphamide in low doses upon the onset of delayed type hypersensitivity in mice chronically infected with Trypanosoma cruzi: involvement of heart interstitial dendritic cells.

Acute infection with Trypanosoma cruzi results in intense myocarditis, which progresses to a chronic, asymptomatic indeterminate form. The evolution toward this chronic cardiac form occurs in approximately 30% of all cases of T. cruzi infection. Suppression of delayed type hypersensitivity (DTH) has been proposed as a potential explanation of the indeterminate form. We investigated the effect of cyclophosphamide (CYCL) treatment on the regulatory mechanism of DTH and the participation of heart interstitial dendritic cells (IDCs) in this process using BALB/c mice chronically infected with T. cruzi. One group was treated with CYCL (20 mg/kg body weight) for one month. A DTH skin test was performed by intradermal injection of T. cruzi antigen (3 mg/mL) in the hind-footpad and measured the skin thickness after 24 h, 48 h and 72 h. The skin test revealed increased thickness in antigen-injected footpads, which was more evident in the mice treated with CYCL than in those mice that did not receive treatment. The thickened regions were characterised by perivascular infiltrates and areas of necrosis. Intense lesions of the myocardium were present in three/16 cases and included large areas of necrosis. Morphometric evaluation of lymphocytes showed a predominance of TCD8 cells. Heart IDCs were immunolabelled with specific antibodies (CD11b and CD11c) and T. cruzi antigens were detected using a specific anti-T. cruzi antibody. Identification of T. cruzi antigens, sequestered in these cells using specific anti-T. cruzi antibodies was done, showing a significant increase in the number of these cells in treated mice. These results indicate that IDCs participate in the regulatory mechanisms of DTH response to T. cruzi infection.

Effect of treatment with cyclophosphamide in low doses upon the onset of delayed type hypersensitivity in mice chronically infected with Trypanosoma cruzi: involvement of heart interstitial dendritic cells

Acute infection with Trypanosoma cruzi results in intense myocarditis, which progresses to a chronic, asymptomatic indeterminate form. The evolution toward this chronic cardiac form occurs in approximately 30% of all cases of T. cruzi infection. Suppression of delayed type hypersensitivity (DTH) has been proposed as a potential explanation of the indeterminate form. We investigated the effect of cyclophosphamide (CYCL) treatment on the regulatory mechanism of DTH and the participation of heart interstitial dendritic cells (IDCs) in this process using BALB/c mice chronically infected with T. cruzi. One group was treated with CYCL (20 mg/kg body weight) for one month. A DTH skin test was performed by intradermal injection of T. cruzi antigen (3 mg/mL) in the hind-footpad and measured the skin thickness after 24 h, 48 h and 72 h. The skin test revealed increased thickness in antigen-injected footpads, which was more evident in the mice treated with CYCL than in those mice that did not receive treatment. The thickened regions were characterised by perivascular infiltrates and areas of necrosis. Intense lesions of the myocardium were present in three/16 cases and included large areas of necrosis. Morphometric evaluation of lymphocytes showed a predominance of TCD8 cells. Heart IDCs were immunolabelled with specific antibodies (CD11b and CD11c) and T. cruzi antigens were detected using a specific anti-T. cruzi antibody. Identification of T. cruzi antigens, sequestered in these cells using specific anti-T. cruzi antibodies was done, showing a significant increase in the number of these cells in treated mice. These results indicate that IDCs participate in the regulatory mechanisms of DTH response to T. cruzi infection.

Biological, biochemical and molecular features of Trypanosoma cruzi strains isolated from patients infected through oral transmission during a 2005 outbreak in the state of Santa Catarina, Brazil: its correspondence with the new T. cruzi Taxonomy Consensus (2009)

We examined strains of Trypanosoma cruzi isolated from patients with acute Chagas disease that had been acquired by oral transmission in the state of Santa Catarina, Brazil (2005) and two isolates that had been obtained from a marsupial (Didelphis aurita) and a vector (Triatoma tibiamaculata). These strains were characterised through their biological behaviour and isoenzymic profiles and genotyped according to the new Taxonomy Consensus (2009) based on the discrete typing unities, that is, T. cruzi genotypes I-VI. All strains exhibited the biological behaviour of biodeme type II. In six isolates, late peaks of parasitaemia, beyond the 20th day, suggested a double infection with biodemes II + III. Isoenzymes revealed Z2 or mixed Z1 and Z2 profiles. Genotyping was performed using three polymorphic genes (cytochrome oxidase II, spliced leader intergenic region and 24Sα rRNA) and the restriction fragment length polymorphism of the kDNA minicircles. Based on these markers, all but four isolates were characterised as T. cruzi II genotypes. Four mixed populations were identified: SC90, SC93 and SC97 (T. cruzi I + T. cruzi II) and SC95 (T. cruzi I + T. cruzi VI). Comparison of the results obtained by different methods was essential for the correct identification of the mixed populations and major lineages involved indicating that characterisation by different methods can provide new insights into the relationship between phenotypic and genotypic aspects of parasite behaviour.

Biological, biochemical and molecular features of Trypanosoma cruzi strains isolated from patients infected through oral transmission during a 2005 outbreak in the state of Santa Catarina, Brazil: its correspondence with the new T. cruzi Taxonomy Consensus (2009).

We examined strains of Trypanosoma cruzi isolated from patients with acute Chagas disease that had been acquired by oral transmission in the state of Santa Catarina, Brazil (2005) and two isolates that had been obtained from a marsupial (Didelphis aurita) and a vector (Triatoma tibiamaculata). These strains were characterised through their biological behaviour and isoenzymic profiles and genotyped according to the new Taxonomy Consensus (2009) based on the discrete typing unities, that is, T. cruzi genotypes I-VI. All strains exhibited the biological behaviour of biodeme type II. In six isolates, late peaks of parasitaemia, beyond the 20th day, suggested a double infection with biodemes II + III. Isoenzymes revealed Z2 or mixed Z1 and Z2 profiles. Genotyping was performed using three polymorphic genes (cytochrome oxidase II, spliced leader intergenic region and 24Sα rRNA) and the restriction fragment length polymorphism of the kDNA minicircles. Based on these markers, all but four isolates were characterised as T. cruzi II genotypes. Four mixed populations were identified: SC90, SC93 and SC97 (T. cruzi I + T. cruzi II) and SC95 (T. cruzi I + T. cruzi VI). Comparison of the results obtained by different methods was essential for the correct identification of the mixed populations and major lineages involved indicating that characterisation by different methods can provide new insights into the relationship between phenotypic and genotypic aspects of parasite behaviour.

Reinfections with strains of Trypanosoma cruzi, of different biodemes as a factor of aggravation of myocarditis and myositis in mice.

Reinfections with Trypanosoma cruzi in patients from endemic areas have been claimed to be an aggravation factor of cardiac manifestations in Chagas' disease. In the present study, the influence of triple infections with strains of different biodemes, on cardiac and skeletal muscle lesions was experimentally tested. Fifty eight mice chronically infected with the Colombian strain (Biodeme Type III) were successively reinfected as follows: 1st group--reinfected with 21 SF strain (Type II) followed by Y strain (Type I ); 2nd--group reinfections with Y strain followed by 21SF strain. Isoenzyme analysis of parasites from hemocultures obtained from triple infected mice, revealed the patterns of three distinct zymodemes in the same animal. Each Trypanosoma cruzi strain was reisolated after four passages in mice on either the 7th, 14th or 30th day after inoculation with the blood of triple infected mice. Histopathology results demonstrated a significant exacerbation of cardiac and skeletal muscle inflammatory lesions, confirmed by morphometric evaluation, in mice with triple infection. No aggravation of parasitism was detected. The possibility of an enhancement of cellular response in the triple infected mice is suggested.

Reinfections with strains of Trypanosoma cruzi, of different biodemes as a factor of aggravation of myocarditis and myositis in mice

Reinfeccões pelo Trypanosoma cruzi em pacientes de áreas endêmicas têm sido mencionadas como fator agravante das manifestacões cardíacas na doenca de Chagas. No presente estudo, a influência da tríplice infeccão com cepas de diferentes biodemas, sobre as lesões do miocárdio e de músculo esquelético foi investigada experimentalmente. Cinqüenta e oito camundongos cronicamente infectados com a cepa Colombiana do Trypanosoma cruzi (Biodema Tipo III) foram sucessivamente reinoculadas como a seguir: 1º grupo - reinfectados com a cepa 21 SF (Tipo II) seguido pela cepa Y (Tipo I); 2º grupo - reinfeccão com a cepa Y seguida pela cepa 21SF. A análise isoenzimática dos parasitas das hemoculturas obtidas dos animais com tríplice infeccão, revelou os padrões dos diferentes zimodemas no mesmo animal. Cada cepa do Trypanosoma cruzi foi re-isolada após quatro passagens em camundongos no 7º, no 14º, ou no 30º dia após a inoculacão com o sangue de camundongos com tríplice infeccão. Resultados da histopatologia demonstraram uma significante exacerbacão das lesões inflamatórias de miocárdio e músculo esquelético, confirmadas pela avaliacão morfométrica. Não foi detectada acentuacão do parasitismo. A possibilidade de aumento da resposta celular nos animais com tríplice infeccão é sugerida.

Response to chemotherapy with benznidazole of clones isolated from the 21SF strain of Trypanosoma cruzi (biodeme Type II, Trypanosoma cruzi II).

Susceptibility to chemotherapy with benznidazole was investigated of 5 clones isolated from the 21 SF strain (biodeme Type II, Trypanosoma cruzi II). Swiss mice were infected with the parental strain for each clone and submitted to chemotherapy with benznidazole (100mg/kg/day during 90 days). Treatment determined negativity of the parasitemia. Cure rates were evaluated by parasitological cure tests. Serology was evaluated for treated animals (titers from negative to 1:640) and untreated controls (1:160 to 1:640). Cure rates varied from 30 to 100% for the 5 clones, and were 25% for the parental strain. Results suggested that the variability of response to treatment of the clonal populations of Trypanosoma cruzi II strains is responsible for the high variation in the response to chemotherapy with benznidazole and nifurtimox by strains of this biodeme.

Response to chemotherapy with benznidazole of clones isolated from the 21SF strain of Trypanosoma cruzi (biodeme Type II, Trypanosoma cruzi II)

A suscetibilidade à quimioterapia com o benzonidazol, de 5 clones isolados da cepa 21SF (biodema Tipo II, T. cruzi II), foi investigada. Camundongos suíços foram infectados com a cepa parental e com cada clone e submetidos à quimioterapia com benzonidazol (100mg/k/dia durante 90 dias). Os índices de cura foram avaliados pelos testes de cura parasitológicos. A sorologia foi avaliada para os animais tratados e (de negativo a 1: 640) e para os controles não tratados( 1:160 a 1:640). Os índices de cura variaram de 30% a 100% para os 5 clones sendo de 25% para a cepa parental. Os resultados sugerem que a variabilidade de resposta ao tratamento das populações clonais das cepas Trypanosoma cruzi II é responsável pela grande variação na resposta à quimioterapia com benzonidazol e nifurtimox das cepas deste biodema.