Dermatofitose experimental do hamster inoculado com Trychophyton mentagrophytes na bolsa jugal

This study presents the results of T. mentagrophytes inoculation in the cheek pouch of the hamster, an immunologically privileged site. Forty two animals were used: 21 inoculated with 10(6) fungi in the cheek pouch (group 1) and 21 inoculated initially with 10(6) fungi in the foot pad and 15 days later in the cheek pouch, with the same amount of fungi (group 2). Animals were sacrificed at 20 hours, 3, 7, 14, 30, 60, and 120 days; samples from inoculated cheek pouch, and foot pads submitted to the foot pad test (FPT), were collected. Independent of group and time of evolution of infection, animals did not develop delayed hypersensitivity evaluated through the FPT. The pre-inoculation of fungi in the foot pad did not change the morphology of lesions induced in the cheek pouch. Therefore, in animals of group 1 and 2, the introduction of the fungus in the cheek pouch resulted in focal lesion composed of a sterile acute inflammatory infiltrate, with abscess formation that evolved to a macrophagic reaction, and later to resolution even in the absence of immune response detectable by FPT. Our results indicate that in spite of the important role of the immune response in the spontaneous regression of dermatophytosis, other factors are also an integral part in the defense against this fungal infection.Esse estudo apresenta os resultados obtidos quando da inoculação de Trychophyton mentagrophytes na bolsa jugal do hamster, local imunologicamente privilegiado. Foram utilizados 42 animais: 21 inoculados com 10(6) fungos na bolsa jugal (grupo 1) e, 21 inicialmente inoculados com 10(6) fungos no coxim plantar e, 15 dias após, na bolsa jugal com a mesma quantidade fúngica (grupo 2). Os animais foram sacrificados às 20 h, 3, 7, 14, 30, 60 e 120 dias; foram coletadas amostras da bolsa jugal inoculada, e das patas submetidas ao teste do coxim plantar (TCP). Independente do grupo e do tempo de evolução da infecção, os animais não desenvolveram hipersensibilidade tardia avaliada através do TCP. A pré-inoculação de fungos no coxim plantar não alterou a morfologia das lesões induzidas na bolsa jugal. Assim, nos animais do grupo 1 e grupo 2, a introdução do fungo na bolsa jugal, resultou em lesão focal, constituída por infiltrado inflamatório agudo estéril, com formação de abscesso, que evoluiu para reação macrofágica e, posteriormente, para a resolução mesmo na ausência de resposta imune detectável pelo TCP. Nossos resultados indicam que, apesar do importante papel da resposta imune na regressão espontânea da dermatofitose, outros fatores são, também, parte integral da defesa contra esta infecção fúngica

In vitro and in situ activation of the complement system by the fungus Lacazia loboi

Since there are no studies evaluating the participation of the complement system (CS) in Jorge Lobo's disease and its activity on the fungus Lacazia loboi, we carried out the present investigation. Fungal cells with a viability index of 48% were obtained from the footpads of BALB/c mice and incubated with a pool of inactivated serum from patients with the mycosis or with sterile saline for 30 min at 37 ºC. Next, the tubes were incubated for 2 h with a pool of noninactivated AB+ serum, inactivated serum, serum diluted in EGTA-MgCl2, and serum diluted in EDTA. The viability of L. loboi was evaluated and the fungal suspension was cytocentrifuged. The slides were submitted to immunofluorescence staining using human anti-C3 antibody. The results revealed that 98% of the fungi activated the CS by the alternative pathway and no significant difference in L. loboi viability was observed after CS activation. In parallel, frozen histological sections from 11 patients were analyzed regarding the presence of C3 and IgG by immunofluorescence staining. C3 and IgG deposits were observed in the fungal wall of 100% and 91% of the lesions evaluated, respectively. The results suggest that the CS and immunoglobulins may contribute to the defense mechanisms of the host against L. loboi.Considerando que não existe nenhum estudo avaliando a participação do sistema complemento (SC) na doença de Jorge Lobo e sua atividade sobre o fungo Lacazia loboi, realizamos o presente trabalho. Os fungos foram obtidos dos coxins plantares de camundongos BALB/c com índice de viabilidade de 48% e, em seguida, foram incubados com pool de soro inativado de pacientes ou com solução salina estéril (SSE) por 30 min, a 37 ºC. Os tubos foram incubados, por 2 h, com pool de soro AB+ sem inativar, inativado, diluído em EGTA-MgCl2 e EDTA. A viabilidade do L. loboi foi avaliada e a suspensão fúngica foi citocentrifugada. As lâminas foram submetidas à técnica de imunofluorescência empregando o anticorpo anti-C3 humano. Os resultados revelaram que 98% dos fungos ativaram o SC pela via alternativa e que não houve diferença significante na viabilidade do L. loboi após ativação do SC. Em paralelo, cortes histológicos congelados de 11 pacientes foram avaliados quanto à presença de C3 e IgG, pela técnica de imunofluorescência. Foram encontrados depósitos de C3 e de IgG na parede dos fungos em 100% e 91% das lesões avaliadas, respectivamente. Os resultados sugerem que o SC e as imunoglobulinas poderiam contribuir nos mecanismos de defesa do hospedeiro contra o L. loboi

Eficácia do álcool etílico e quaternário de amônio na desinfecção de equipamentos médicos hospitalares

Background and Objectives: Hospital environments may harbor pathogenic and opportunistic microorganisms, and the cleaning and disinfection process is important for the control of Health Care Related Infections (IRAS). Thus, the objective of this work to evaluate compare the efficacy of ethyl alcohol and quaternary ammonium in the disinfection of hospital medical equipment against Staphylococcus aureus (S. aureus). Methods: decontamination of 10 hospital medical equipment contaminated with a suspension of S. aureus ATCC 25923. The decontamination occurred with ethyl alcohol at concentrations of 46.2%, 70% and 99% and with the quaternary ammonium of 1st generation and 5th generation. After the decontamination, samples were harvested from the surface of the equipment for bacterial culture. Results: bacterial growth was verified in 80% of the equipment decontaminated with alcohol 46.2% and 99%. There was no bacterial growth on the surface of equipment decontaminated with alcohol 70% and quaternary ammonium. Conclusions: the disinfection processes with alcohol 70% and quaternary ammonium 1st and 5th generation were effective in the control of S. aureus, proving the effectiveness of these products in the disinfection of hospital medical equipment.Antecedentes y objetivos: Los ambientes hospitalarios pueden albergar microorganismos patógenos y oportunistas, siendo el proceso de limpieza y desinfección importante para el control de las Infecciones relacionadas a la Asistencia a la Salud (IRAS). Así, el objetivo de este trabajo evaluar comparar la eficacia del alcohol etílico y del cuaternario de amonio en el proceso de desinfección de equipos médicos hospitalarios previamente contaminados con Staphylococcus aureus (S. aureus). Métodos: la descontaminación de 10 equipos médicos hospitalarios contaminados con una suspensión de S. aureus ATCC 25923. La descontaminación ocurrió con alcohol etílico en las concentraciones de 46,2%, 70% y 99% y con el cuaternario de amonio de 1ª y de 5ª generación. Después de la descontaminación, se tomaron muestras de la superficie de los equipos para cultivo bacteriano. Resultados: se verificó crecimiento bacteriano en el 80% de los equipos descontaminados con alcohol 46,2% y 99%. No hubo crecimiento bacteriano en la superficie de los equipos descontaminados con alcohol 70% y cuaternarios de amonio. Conclusión: los procesos de desinfección con alcohol 70% y cuaternario de amonio de 1ª y 5ª generación fueron eficaces en el control del S. aureus, comprobando la acción efectiva de estos productos en la desinfección de los equipos médicos hospitalarios.Justificativa e Objetivo: Os ambientes hospitalares podem albergar micro-organismos patogênicos e oportunistas, sendo o processo de limpeza e desinfecção importante para o controle das Infecções relacionadas à Assistência à Saúde (IRAS). Assim, o objetivo deste trabalho foi avaliar a eficácia do álcool etílico e do quaternário de amônio no processo de desinfecção de equipamentos médicos hospitalares previamente contaminados com Staphylococcus aureus (S. aureus). Método: descontaminação de 10 equipamentos médicos hospitalares contaminados com uma suspensão de S. aureus ATCC 25923. A descontaminação ocorreu com álcool etílico nas concentrações de 46,2%, 70% e 99% e com o quaternário de amônio de 1ª e de 5ª geração. Após a descontaminação, foram colhidas amostras da superfície dos equipamentos para cultura bacteriana. Resultados: foi verificado crescimento bacteriano em 80% dos equipamentos descontaminados com álcool 46,2% e 99%. Não houve crescimento bacteriano na superfície dos equipamentos descontaminados com álcool 70% e quaternários de amônio. Conclusão: os processos de desinfecção com álcool 70% e quaternário de amônio de 1ª e 5ª geração foram eficazes no controle do S. aureus, comprovando a ação efetiva destes produtos na desinfecção dos equipamentos médicos hospitalares

Efficacy of ethyl alcohol and quaternary ammonium in hospital medical equipment disinfection

Background and Objectives: Hospital environments may harbor pathogenic and opportunistic microorganisms, and the cleaning and disinfection process is important for the control of Health Care Related Infections (IRAS). Thus, the objective of this work to evaluate compare the efficacy of ethyl alcohol and quaternary ammonium in the disinfection of hospital medical equipment against Staphylococcus aureus (S. aureus). Methods: decontamination of 10 hospital medical equipment contaminated with a suspension of S. aureus ATCC 25923. The decontamination occurred with ethyl alcohol at concentrations of 46.2%, 70% and 99% and with the quaternary ammonium of 1st generation and 5th generation. After the decontamination, samples were harvested from the surface of the equipment for bacterial culture. Results: bacterial growth was verified in 80% of the equipment decontaminated with alcohol 46.2% and 99%. There was no bacterial growth on the surface of equipment decontaminated with alcohol 70% and quaternary ammonium. Conclusion: the disinfection processes with alcohol 70% and quaternary ammonium 1st and 5th generation were effective in the control of S. aureus, proving the effectiveness of these products in the disinfection of hospital medical equipment

In vitro and in situ activation of the complement system by the fungus Lacazia loboi

Since there are no studies evaluating the participation of the complement system (CS) in Jorge Lobo's disease and its activity on the fungus Lacazia loboi, we carried out the present investigation. Fungal cells with a viability index of 48% were obtained from the footpads of BALB/c mice and incubated with a pool of inactivated serum from patients with the mycosis or with sterile saline for 30 min at 37 ºC. Next, the tubes were incubated for 2 h with a pool of noninactivated AB+ serum, inactivated serum, serum diluted in EGTA-MgCl2, and serum diluted in EDTA. The viability of L. loboi was evaluated and the fungal suspension was cytocentrifuged. The slides were submitted to immunofluorescence staining using human anti-C3 antibody. The results revealed that 98% of the fungi activated the CS by the alternative pathway and no significant difference in L. loboi viability was observed after CS activation. In parallel, frozen histological sections from 11 patients were analyzed regarding the presence of C3 and IgG by immunofluorescence staining. C3 and IgG deposits were observed in the fungal wall of 100% and 91% of the lesions evaluated, respectively. The results suggest that the CS and immunoglobulins may contribute to the defense mechanisms of the host against L. loboi