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The aims of this study are to: (1) describe the prevalence and sociodemographic characteristics of inhalant use among middle and high school students in Brazil, and (2) test the hypothesis of inhalants being intermediate drugs between legal and illegal drug use. A representative sample of 5226 students from private schools in São Paulo, Brazil, was selected to answer a self-report questionnaire. Weighted data was analyzed through Cox proportional hazards models. In the overall sample, inhalants seems to be an intermediate drug, since prior inhalant initiation was associated with first marijuana use, adjusted for previous alcohol and tobacco initiation.

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OBJETIVO: Compreender a fissura do usuário de crack, bem como descrever os comportamentos desenvolvidos sob fissura e estratégias utilizadas para seu controle. PROCEDIMENTOS METODOLÓGICOS: Estudo qualitativo com amostra intencional por critérios de 40 usuários e ex-usuários de crack em São Paulo, SP, nos anos de 2007 e 2008. Os entrevistados foram recrutados pela técnica da bola de neve e submetidos à entrevista semi-estruturada em profundidade, até a saturação teórica. Após transcrição literal, seguiu-se a análise do conteúdo das entrevistas para elaboração de inferências e hipóteses alicerçadas nessas narrativas. ANÁLISE DOS RESULTADOS: Os entrevistados estavam igualmente distribuídos quanto ao sexo, possuíam idade entre 18 e 50 anos, abrangeram todos os níveis de escolaridade e a maior parte possuía poucos recursos financeiros. Além da fissura sentida na abstinência de crack e da fissura induzida por pistas ambientais e emocionais, constatou-se um tipo de fissura que faz parte do próprio efeito do crack. Esta última apareceu como forte fator mantenedor dos binges de consumo, que foram os maiores responsáveis pelo rebaixamento de valores do usuário, sujeitando-o a práticas arriscadas para a obtenção da droga. Os métodos mais citados para a obtenção de crack ou dinheiro para comprá-lo foram: prostituição, manipulação de pessoas, endividamento, troca de pertences por crack e roubo. Foram relatadas estratégias para o alívio da fissura e táticas farmacológicas e comportamentais para evitar o seu desenvolvimento, como: comer, ter relação sexual, jogar futebol, trabalhar, evitar o contexto social de uso de crack e usar drogas que causam sonolência. CONCLUSÕES: Os binges de consumo de crack são causados pela fissura induzida durante o uso da droga. As medidas criadas pelo próprio usuário para lidar com a sua fissura melhoram sua relação com o crack e podem ser ferramenta importante para o aprimoramento do tratamento.

OBJECTIVE: To understand crack cocaine craving among users and describe craving behaviors and coping strategies. METHODOLOGICAL PROCEDURES: Qualitative study with a non-random criterion sample consisting of 40 current and former crack cocaine users conducted in São Paulo, southeast Brazil, in 2007 and 2008. Respondents were selected using snowball sampling technique. In-depth semi-structured interviews were conducted until theoretical saturation was attained. All interviews were transcribed and content analysis was performed to construct inferences and hypotheses based on the narratives. ANALYSIS OF RESULTS: The respondents showed a similar gender distribution, were 18 to 50 years of age, and had different levels of education. Most were from low-income background. In addition to craving resulting from crack cocaine withdrawal and environmental and emotional cue effects, it was found that crack cocaine itself triggers craving. The latter appeared to be a strong trigger of binge episodes. Binge episodes made them lose their moral values, and act dangerously to get more drug. The most common ways reported to get crack cocaine or money to buy it were: prostitution, manipulation of other people, go into debt, sell personal belongings to buy drug and theft. The respondents reported strategies to overcome their cravings as well as pharmacological and behavioral approaches to prevent cravings such as eating, having sex, playing soccer, working, avoiding social situations of crack use and taking depressants. CONCLUSIONS: Crack cocaine binges are caused by a craving induced by the effects of crack cocaine itself. Users develop self-control strategies to cope with their cravings that may help improve their drug use and treatment effectiveness.

OBJETIVO: Comprender el ansia de consumo por el usuario de crack, así como describir las conductas desarrolladas y estrategias utilizadas para su control. PROCEDIMIENTOS METODOLÓGICOS: Estudio cualitativo con muestra intencional por criterios de 40 usuarios y ex-usuarios de crack en Sao Paulo, Sureste de Brasil, en los años de 2007 y 2008. Los entrevistados fueron reclutados por la técnica de la bola de nieve y sometidos a la entrevista semi-estructurada en profundidad, hasta la saturación teórica. Posterior a la transcripción literal, se realizó el análisis de contenido de las entrevistas para elaboración de inferencias e hipótesis cimentadas en estas narrativas. ANÁLISIS DE RESULTADOS: Los entrevistados estaban igualmente distribuidos con respecto al sexo, poseían edad entre 18 y 50 años, abarcaron todos los niveles de escolaridad y la mayor parte poseía pocos recursos financieros. Se identificó sensación de ansia de consumo en la abstinencia de crack, inducida por señales ambientales y emocionales, como efecto de la droga. Esta última apareció como fuerte factor mantenedor de los consumos excesivos, que fueron los mayores responsables por el apocamiento de los valores del usuario, sujetándolos a prácticas arriesgadas para la obtención de drogas. Los métodos más citados para la obtención de crack o dinero para comprarlo fueron: prostitución, manipulación de personas, endeudamiento, cambio de pertenencias por crack y robo. Se relataron estrategias para el alivio del ansia de consumo y tácticas farmacológicas y conductuales para evitar su desarrollo, como: comer, tener relación sexual, jugar fútbol, trabajar, evitar el contexto social de uso de crack y usar drogas que causan somnolencia. CONCLUSIONES: Los consumos excesivos de crack son causados por el ansia de consumo inducido durante el uso de la droga. Las medidas creadas por el propio usuario para lidiar con su ansiedad mejoran su relación con el crack y pueden ser herramienta importante para perfeccionar el tratamiento.

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OBJECTIVE: To understand crack cocaine craving among users and describe craving behaviors and coping strategies. METHODOLOGICAL PROCEDURES: Qualitative study with a non-random criterion sample consisting of 40 current and former crack cocaine users conducted in São Paulo, southeast Brazil, in 2007 and 2008. Respondents were selected using snowball sampling technique. In-depth semi-structured interviews were conducted until theoretical saturation was attained. All interviews were transcribed and content analysis was performed to construct inferences and hypotheses based on the narratives. ANALYSIS OF RESULTS: The respondents showed a similar gender distribution, were 18 to 50 years of age, and had different levels of education. Most were from low-income background. In addition to craving resulting from crack cocaine withdrawal and environmental and emotional cue effects, it was found that crack cocaine itself triggers craving. The latter appeared to be a strong trigger of binge episodes. Binge episodes made them lose their moral values, and act dangerously to get more drug. The most common ways reported to get crack cocaine or money to buy it were: prostitution, manipulation of other people, go into debt, sell personal belonging to buy drug and theft. The respondents reported strategies to overcome their cravings as well as pharmacological and behavioral approaches to prevent cravings such as eating, having sex, playing soccer, working, avoiding social situations of crack use and taking depressants. CONCLUSIONS: Crack cocaine binges are caused by a craving induced by the effects of crack cocaine itself. Users develop self-control strategies to cope with their cravings that may help improve their drug use and treatment effectiveness.

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BACKGROUND: Due to marginalization, trafficking violence, conflicts with the police and organic and social psychological problems associated with the drug, crack is one of the most devastating drugs currently in use. However, there is evidence that some users manage to stay alive and active while using crack cocaine for many years, despite the numerous adversities and risks involved with this behavior. In this context, the aim of the present study was to identify the strategies and tactics developed by crack users to deal with the risks associated with the culture of use by examining the survival strategies employed by long-term users. METHOD: A qualitative research method was used involving semi-structured, in-depth interviews. Twenty-eight crack users fulfilling a pre-defined enrollment criterion were interviewed. This criterion was defined as the long-term use of crack (i.e., at least four years). The sample was selected using information provided by key informants and distributed across eight different supply chains. The interviews were literally transcribed and analyzed via content analysis techniques using NVivo-8 software. RESULTS: There was diversity in the sample with regard to economic and education levels. The average duration of crack use was 11.5 years. Respondents believed that the greatest risks of crack dependence were related to the drug's psychological effects (e.g., cravings and transient paranoid symptoms) and those arising from its illegality (e.g., clashes with the police and trafficking). Protection strategies focused on the control of the psychological effects, primarily through the consumption of alcohol and marijuana. To address the illegality of the drug, strategies were developed to deal with dealers and the police; these strategies were considered crucial for survival. CONCLUSIONS: The strategies developed by the respondents focused on trying to protect themselves. They proved generally effective, though they involved risks of triggering additional problems (e.g., other dependencies) in the long term.

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BACKGROUND: Brucella abortus is a facultative intracellular pathogen that mainly infects cattle and humans. Current vaccines rely on live attenuated strains of B. abortus, which can revert to their pathogenic status and thus are not totally safe for use in humans. Therefore, the development of mucosal live vaccines using the food-grade lactic acid bacterium, Lactococcus lactis, as an antigen delivery vector, is an attractive alternative and a safer vaccination strategy against B. abortus. Here, we report the construction of L. lactis strains genetically modified to produce B. abortus GroEL heat-shock protein, a candidate antigen, in two cellular locations, intracellular or secreted. RESULTS: Only the secreted form of GroEL was stably produced in L. lactis, suggesting a detrimental effect of GroEL protein when intracellularly produced in this bacterium. Only trace amounts of mature GroEL were detected in the supernatant fraction of induced lactococcal cultures, and the GroEL precursor remained stacked in the cell fraction. Attempts to raise the secretion yields were made, but even when GroEL was fused to a synthetic propeptide, secretion of this antigen was not improved. CONCLUSION: We found that L. lactis is able to produce, and to secrete, a stable form of GroEL into the extracellular medium. Despite the low secretion efficiency of GroEL, which suggest that this antigen interacts with the cell envelope of L. lactis, secretion seems to be the best way to achieve both production and protein yields, regardless of cellular location. The L. lactis strain secreting GroEL has potential for in vivo immunization.

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Lactic acid bacteria (LAB), widely used in the food industry, are present in the intestine of most animals, including humans. The potential use of these bacteria as live vehicles for the production and delivery of heterologous proteins of vaccinal, medical or technological interest has therefore been extensively investigated. Lactococcus lactis, a LAB species, is a potential candidate for the production of biologically useful proteins. Several delivery systems have been developed to target heterologous proteins to a specific cell location (i.e., cytoplasm, cell wall or extracellular medium). A promising application of L. lactis is its use as an antigen delivery vehicle, for the development of live mucosal vaccines. The expression of heterologous proteins and antigens as well as the various delivery systems developed in L. lactis, and its use as an oral vaccine carrier are discussed.

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The Brucella abortus ribosomal protein L7/L12 is an immunodominant antigen and an interesting candidate for the development of oral live vaccines against brucellosis. Here, a recombinant Lactococcus lactis strain producing L7/L12 under the control of nisin inducible promoter was orally administered to BALB/c mice. Significant levels of anti-L7/L12 specific IgA detected in feces revealed an induced local humoral immune response. However, serum analysis did not reveal any anti-L7/L12 antibodies suggesting the absence of a systemic response. Nevertheless, the vaccinated mice showed a partial protective immunity against B. abortus virulent strain (S2308) challenged by intraperitoneal inoculation.

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Ovos fertilizados de galinha foram bombardeados através da técnica de biobalística. A expressäo transiente do gene lacZ, sob o controle do promotor humano citomegalovírus, foi verificada após a transferência in situ. Diferentes níveis de pressäo de gás hélio, vácuo e tipos de partículas foram testados. A taxa de sobrevivência aumentou à medida que a velocidade das partículas diminuíram, entretanto, o nível de expressäo foi menor. Os melhores resultados, combinando taxa de sobrevivência e expressäo, foram obtidos com partículas de ouro, 600 libras por polegada ao quadrado de hélio e 600 mmHg de vácuo. Nestas condiçöes, todos os embriöes bombardeados apresentaram atividade da ß-galactosidase, indicando que esta técnica é eficiente para a transformaçäo de embriöes de galinha.

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