RESUMO
The widespread and sustainable exploitation of the entomopathogen Bacillus thuringiensis (Bt) in pest control is threatened by the evolution of resistance. Although resistance is often associated with loss of binding of the Bt toxins to the insect midgut cells, other factors have been implicated. Here we used suppressive subtractive hybridization and gene expression suppression to identify additional molecular components involved in Bt-resistance in Plutella xylostella. We isolated transcripts from genes that were differentially expressed in the midgut of larvae from a resistant population, following ingestion of a Bt kurstaki HD1 strain-based commercial formulation (DiPel), and compared with a genetically similar susceptible population. Quantitative real-time polymerase-chain reaction (RT-PCR) analysis confirmed the differential basal expression of a subset of these genes. Gene expression suppression of three of these genes (P. xylostella cyclin-dependent kinase 5 regulatory subunit associated protein 1-like 1, stromal cell-derived factor 2-like 1 and hatching enzyme-like 1) significantly increased the pathogenicity of HD1 to the resistant population. In an attempt to link the multitude of factors reportedly influencing resistance to Bt with the well-characterized loss of toxin binding, we also considered Bt-resistance models in P. xylostella and other insects.
Assuntos
Bacillus thuringiensis , Agentes de Controle Biológico , Proteínas de Insetos/metabolismo , Resistência a Inseticidas/genética , Mariposas/metabolismo , Animais , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Endotoxinas/genética , Endotoxinas/metabolismo , Trato Gastrointestinal/metabolismo , Expressão Gênica , Genes de Insetos , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/metabolismo , Proteínas de Insetos/genética , Larva/genética , Larva/metabolismo , Mariposas/genéticaRESUMO
BACKGROUND: The significance of detection of Trypanosoma cruzi DNA in blood of antibody-positive patients for risk of development of Chagas heart disease is not well established. The objective of this study was to compare detection of T. cruzi DNA with known clinical and laboratory markers of Chagas cardiomyopathy (CC) severity. METHODS: This is a case-control study nested within a retrospective cohort developed in Brazil to understand the natural history of Chagas disease. The study enrolled 499 T. cruzi seropositive blood donors (SP-BD) and 488 frequency matched seronegative control donors (SN-BD) who had donated between 1996 and 2002, and 101 patients with clinically diagnosed CC. In 2008-2010 all enrolled subjects underwent a health questionnaire, medical examination, electrocardiograms and echocardiograms and polymerase chain reaction (PCR) analyses. A blinded panel of three cardiologists adjudicated the outcome of CC. Trypanosoma cruzi kinetoplast minicircle sequences were amplified by real-time PCR using an assay with a sensitivity of one parasite per 20 mL of blood. All testing was performed on coded samples. RESULTS: Rates of PCR detection of T. cruzi DNA were significantly (P = 0.003) higher in CC patients and SP-BD diagnosed with CC (79/105 [75.2 %]) compared with SP-BD without CC (143/279 [51.3%]). The presence of parasitaemia was significantly associated with known markers of disease progression such as QRS and QT interval duration, lower left ventricular ejection fraction, higher left ventricular index mass, and elevated troponin and NTpro-BNP levels. CONCLUSION: Trypanosoma cruzi PCR positivity is associated with presence and severity of cardiomyopathy, suggesting a direct role of parasite persistence in disease pathogenesis.
Assuntos
Cardiomiopatia Chagásica/sangue , DNA de Protozoário/sangue , Trypanosoma cruzi/genética , Adulto , Doadores de Sangue , Estudos de Casos e Controles , Cardiomiopatia Chagásica/parasitologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real/métodos , Estudos Retrospectivos , Índice de Gravidade de Doença , Trypanosoma cruzi/patogenicidadeRESUMO
BACKGROUND: Reducing risk of HIV window period transmission requires understanding of donor knowledge and attitudes related to HIV and risk factors. STUDY DESIGN AND METHODS: We conducted a survey of 7635 presenting blood donors at three Brazilian blood centres from 15 October through 20 November 2009. Participants completed a questionnaire on HIV knowledge and attitudes about blood donation. Six questions about blood testing and HIV were evaluated using maximum likelihood chi-square and logistic regression. Test seeking was classified in non-overlapping categories according to answers to one direct and two indirect questions. RESULTS: Overall, respondents were male (64%) repeat donors (67%) between 18 and 49 years old (91%). Nearly 60% believed blood centres use better HIV tests than other places; however, 42% were unaware of the HIV window period. Approximately 50% believed it was appropriate to donate to be tested for HIV, but 67% said it was not acceptable to donate with risk factors even if blood is tested. Logistic regression found that less education, Hemope-Recife blood centre, replacement, potential and self-disclosed test-seeking were associated with less HIV knowledge. CONCLUSION: HIV knowledge related to blood safety remains low among Brazilian blood donors. A subset finds it appropriate to be tested at blood centres and may be unaware of the HIV window period. These donations may impose a significant risk to the safety of the blood supply. Decreasing test-seeking and changing beliefs about the appropriateness of individuals with behavioural risk factors donating blood could reduce the risk of transfusing an infectious unit.
Assuntos
Doadores de Sangue , Infecções por HIV/diagnóstico , Adolescente , Adulto , Segurança do Sangue , Brasil , Estudos Transversais , Cultura , Feminino , Infecções por HIV/sangue , Infecções por HIV/prevenção & controle , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Programas de Rastreamento/normas , Pessoa de Meia-Idade , Fatores de Risco , Inquéritos e Questionários , Adulto JovemRESUMO
BACKGROUND: Although risk factors for HIV infection are known, it is important for blood centres to understand local epidemiology and disease transmission patterns. Current risk factors for HIV infection in blood donors in Brazil were assessed. METHODS: A case-control study was conducted at large public blood centres located in four major cities between April 2009 and March 2011. Cases were persons whose donations were confirmed positive by enzyme immunoassays followed by Western blot confirmation. Audio computer-assisted structured interviews (ACASI) were completed by all cases and controls. Multivariable logistic regression was used to estimate adjusted odds ratios (AORs) and associated 95% confidence intervals (CIs). RESULTS: There were 341 cases, including 47 with recently acquired infection, and 791 controls. Disclosed risk factors for both females and males were sex with an HIV-positive person AOR 11.3, 95% CI (4.1, 31.7) and being an IVDU or sexual partner of an IVDU [AOR 4.65 (1.8, 11.7)]. For female blood donors, additional risk factors were having male sex partners who also are MSM [AOR 13.5 (3.1, 59.8)] and having unprotected sex with multiple sexual partners [AOR 5.19 (2.1, 12.9)]. The primary risk factor for male blood donors was MSM activity [AOR 21.6 (8.8, 52.9)]. Behaviours associated with recently acquired HIV were being a MSM or sex partner of MSM [13.82, (4.7, 40.3)] and IVDU [11.47, (3.0, 43.2)]. CONCLUSION: Risk factors in blood donors parallel those in the general population in Brazil. Identified risk factors suggest that donor compliance with selection procedures at the participating blood centres is inadequate.
Assuntos
Doadores de Sangue , Infecções por HIV/sangue , Infecções por HIV/epidemiologia , HIV-1 , Auditoria Médica , Adolescente , Brasil/epidemiologia , Estudos de Casos e Controles , Feminino , Infecções por HIV/prevenção & controle , Humanos , Masculino , Fatores de Risco , Assunção de Riscos , Sexo sem ProteçãoRESUMO
BACKGROUND AND OBJECTIVES: Higher risk of HIV infection could be associated with test seeking, which is one motivation for donating blood. Cognitive social capital is defined as the social support, trust and co-operation that guide community behaviour. Structural social capital refers to an individual's participation in institutions and organizations. The association between social capital and test seeking was assessed. MATERIALS AND METHODS: A survey of over 7500 donors in three Brazilian blood centres was conducted. Test seeking was classified into four non-overlapping categories (non-test seeker, possible, presumed and self-disclosed test seekers) using one direct and two indirect questions. Social capital was summarized into cognitive and structural categorizations. Multivariable logistic regression analysis was performed. RESULTS: Compared with non-test seekers (62% of survey respondents), cognitive social capital was higher for each category of test seeking (OR=1.1, 7.4, 7.1, P<0.05 respectively). Male gender, lower education and lower income were also significantly associated with test seeking. CONCLUSION: As test seekers appear to have strong social networks, blood banks may leverage this to convince them to seek testing at other locations.
Assuntos
Doadores de Sangue/psicologia , Testes Sorológicos/psicologia , Apoio Social , Adolescente , Adulto , Idoso , Brasil , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Sorológicos/métodos , Testes Sorológicos/estatística & dados numéricos , Classe Social , Fatores Socioeconômicos , Adulto JovemRESUMO
OBJECTIVE: To assess the dental health knowledge of primary school teachers, their attitudes toward the prevention of dental diseases and to identify any barriers to the implementation of oral health promotion programmes in schools. METHOD: Teachers' knowledge of the causes and prevention of dental decay and gum disease, their attitudes toward oral health and barriers to the implementation of dental health education programmes were assessed using a self-administered questionnaire. RESULTS: School teachers were generally very well informed about the causes and prevention of dental decay and gum disease. Knowledge of the appropriate management of serious dental trauma was very poor among this group although they seemed to have greater awareness of the appropriate management for less serious dental injuries. The majority of teachers demonstrated positive attitudes toward dental health and its incorporation into the school curriculum. Teachers' attitudes to their own involvement in school-based dental health education were also positive. Lack of training and resources and time within the curriculum were identified as major barriers to the implementation of a dental health education programme in primary schools. CONCLUSION: Developing teacher training programmes that include oral health knowledge and an evidence-based approach to dental health education within a school setting could enable primary school teachers to play a significant part in oral health promotion for young children in Trinidad.
OBJETIVO: Evaluar el conocimiento de los maestros de escuela primaria sobre salud dental, y sus actitudes hacia la prevención de enfermedades dentales, e identificar cualquier barrera a la implementación de programas de promoción de la salud oral en las escuelas. MÉTODO: Haciendo uso de un cuestionario auto-administrado, se evaluó el conocimiento de los maestros sobre las causas y prevención de las caries dentales, y las enfermedades de la encía, así como las actitudes de aquellos hacia la salud oral y las barreras a la aplicación de programas de educación de salud dental. RESULTADOS: Los maestros escolares estaban generalmente muy bien informados acerca de las causas y prevención de las caries dentales y las enfermedades de la encía. El conocimiento sobre el tratamiento apropiado del trauma dental serio era muy pobre entre este grupo, aunque parecían tener mayor conciencia del tratamiento apropiado para las lesiones dentales menos serias. La mayoría de los maestros demostró poseer actitudes positivas hacia la salud dental y su incorporación en el plan de estudios. Las actitudes de los maestros hacia su propia participación en la educación para la salud dental con base en la escuela, fueron también positivas. La falta de entrenamiento, así como de recursos y tiempo dentro del plan de estudios, fueron identificados como las barreras principales a la implementación de un programa de educación de salud dental en las escuelas primarias. CONCLUSIÓN: El desarrollo de programas de entrenamientos para los maestros, que incluyan conocimientos de salud oral y un enfoque de la educación para la salud dental, basado en evidencias, dentro del contexto de la escuela, podría permitirles a los maestros escolares primarios desempeñar un papel significativo en la promoción de la salud oral entre los niños jóvenes en Trinidad.
Assuntos
Adulto , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Educação em Saúde Bucal , Conhecimentos, Atitudes e Prática em Saúde , Serviços de Saúde Escolar/organização & administração , Ensino , Estudos Transversais , Inquéritos e Questionários , Trinidad e TobagoRESUMO
OBJECTIVE: To assess the dental health knowledge of primary school teachers, their attitudes toward the prevention of dental diseases and to identify any barriers to the implementation of oral health promotion programmes in schools. METHOD: Teachers' knowledge of the causes and prevention of dental decay and gum disease, their attitudes toward oral health and barriers to the implementation of dental health education programmes were assessed using a self-administered questionnaire. RESULTS: School teachers were generally very well informed about the causes and prevention of dental decay and gum disease. Knowledge of the appropriate management of serious dental trauma was very poor among this group although they seemed to have greater awareness of the appropriate management for less serious dental injuries. The majority of teachers demonstrated positive attitudes toward dental health and its incorporation into the school curriculum. Teachers'attitudes to their own involvement in school-based dental health education were also positive. Lack of training and resources and time within the curriculum were identified as major barriers to the implementation of a dental health education programme in primary schools. CONCLUSION: Developing teacher training programmes that include oral health knowledge and an evidence-based approach to dental health education within a school setting could enable primary school teachers to play a significant part in oral health promotion for young children in Trinidad.
Assuntos
Educação em Saúde Bucal , Conhecimentos, Atitudes e Prática em Saúde , Serviços de Saúde Escolar/organização & administração , Ensino , Adulto , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Masculino , Inquéritos e Questionários , Trinidad e TobagoRESUMO
Congenital pseudarthrosis of the tibia continues to pose one of the most difficult problems in paediatric orthopaedic surgery. The surgical procedures most used for treating congenital pseudarthrosis of the tibia are intramedullary nailing associated with bone grafting, vascularized fibular graft and the Ilizarov external circular fixator. Even when union is achieved, the residual deformities in the affected limb often result in significant disability. These deformities include leg-length discrepancy, angular tibial deformities, ankle mortise valgus and fibular non-union. The Ilizarov method allows simultaneous excision of the pseudarthrosis site, correction of the deformity and lengthening. However, refractures, ankle joint stiffness, fibular non-union with progressive ankle valgus are frequent sequelae with the Ilizarov technique. The surgeon should know when to abandon reconstructive procedures and create a more functional patient with an amputation. The authors discuss the indications and results of the Ilizarov external fixator in two patients with this complex problem. In addition, a critical review of the current literature is undertaken.
Assuntos
Doenças do Desenvolvimento Ósseo/cirurgia , Fixadores Externos , Ortopedia/métodos , Pseudoartrose/cirurgia , Tíbia/patologia , Resultado do Tratamento , Adolescente , Criança , Humanos , Técnica de Ilizarov , Masculino , Pseudoartrose/genética , Tíbia/cirurgiaRESUMO
Congenital pseudarthrosis of the tibia continues to pose one of the most difficult problems in paediatric orthopaedic surgery. The surgical procedures most used for treating congenital pseudarthrosis of the tibia are intramedullary nailing associated with bone grafting, vascularized fibular graft and the Ilizarov external circular fixator. Even when union is achieved, the residual deformities in the affected limb often result in significant disability. These deformities include leg-length discrepancy, angular tibial deformities, ankle mortise valgus and fibular non-union. The Ilizarov method allows simultaneous excision of the pseudarthrosis site, correction of the deformity and lengthening. However, refractures, ankle joint stiffness, fibular non-union with progressive ankle valgus are frequent sequelae with the Ilizarov technique. The surgeon should know when to abandon reconstructive procedures and create a more functional patient with an amputation. The authors discuss the indications and results of the Ilizarov external fixator in two patients with this complex problem. In addition, a critical review of the current literature is undertaken.
Assuntos
Adolescente , Criança , Humanos , Masculino , Pseudoartrose , Doenças do Desenvolvimento Ósseo/cirurgia , Fixadores Externos , Ortopedia/métodos , Resultado do Tratamento , Tíbia/patologia , Pseudoartrose , Tíbia/cirurgia , Técnica de IlizarovRESUMO
La fascitis Necrotizante (FN) es una emergencia quirúrgica, resultado de la infección de los tejidos subcutáneos y de la fascia superficial, por una gran variedad de bacterias. En esta etapa neonatal, esta afección puede alcanzar una mortalidad mayor al 70 por ciento. El éxito del tratamiento requiere un preciso diagnóstico y precoz y agresivo desbridamiento de los tejidos afectados, la cobertura por vía parenteral de antibióticos de amplio espectro y un soporte adecuado en cuidados intensivos. Reportamos un caso de FN en recién nacidos de sexo masculino, en quien la enfermedad se desencadenó probablemente luego de una onfalitis. Este reporte ilustra la naturaleza devastadora de este tipo de infección, sin embargo, con tratamiento agresivo y precoz es posible lograr resultados satisfactorios.