Global Effects of Catecholamines on Actinobacillus pleuropneumoniae Gene Expression

Bacteria can use mammalian hormones to modulate pathogenic processes that play essential roles in disease development. Actinobacillus pleuropneumoniae is an important porcine respiratory pathogen causing great economic losses in the pig industry globally. Stress is known to contribute to the outcome of A. pleuropneumoniae infection. To test whether A. pleuropneumoniae could respond to stress hormone catecholamines, gene expression profiles after epinephrine (Epi) and norepinephrine (NE) treatment were compared with those from untreated bacteria. The microarray results showed that 158 and 105 genes were differentially expressed in the presence of Epi and NE, respectively. These genes were assigned to various functional categories including many virulence factors. Only 18 genes were regulated by both hormones. These genes included apxIA (the ApxI toxin structural gene), pgaB (involved in biofilm formation), APL_0443 (an autotransporter adhesin) and genes encoding potential hormone receptors such as tyrP2, the ygiY-ygiX (qseC-qseB) operon and narQ-narP (involved in nitrate metabolism). Further investigations demonstrated that cytotoxic activity was enhanced by Epi but repressed by NE in accordance with apxIA gene expression changes. Biofilm formation was not affected by either of the two hormones despite pgaB expression being affected. Adhesion to host cells was induced by NE but not by Epi, suggesting that the hormones affect other putative adhesins in addition to APL_0443. This study revealed that A. pleuropneumoniae gene expression, including those encoding virulence factors, was altered in response to both catecholamines. The differential regulation of A. pleuropneumoniae gene expression by the two hormones suggests that this pathogen may have multiple responsive systems for the two catecholamines

Nurses' training in prehospital care La capacitación de enfermeros para la atención pre-hospitalaria Capacitação de enfermeiros em atendimento pré-hospitalar

The performance of nurses in prehospital care (PHC) assumes acquiring specific competences. The objectives of the present study were to verify nurses' opinion on theoretical knowledge and nursing skills necessary for the practice in pre-hospital setting and to analyze them according to their clinical practice. In this descriptive study, the opinion of nurses, from public pre-hospital care services of the City of São Paulo, was collected through a questionnaire and the data of the clinical practice using forms. Cardiopulmonary resuscitation was mentioned more often as basic knowledge (84%), and the most frequent procedure was oxygen therapy (15.5%). The analysis of nurses' opinion indicated that the basic topics were related to situations that demanded making decisions, readiness and skill under stress or caring for a specific population, making training important in this area.<br>La actuación del enfermero en el área de atención pre-hospitalaria (APH) presupone la adquisición de competencias específicas. Los objetivos de este estudio fueron verificar la opinión de los enfermeros sobre conocimientos teóricos y habilidades de enfermería necesarias para el ejercicio en la APH y analizarlas conforme su práctica clínica. En este estudio descriptivo, la opinión de los enfermeros de los servicios públicos de la APH del Municipio de San Pablo fue recolectada por medio de un cuestionario y los datos de la práctica clínica en un formulario. La resucitación cardiopulmonar fue más citada como conocimiento básico (84%) y el procedimiento más frecuente fue la oxigenoterapia (15,5 %). El análisis de las opiniones de los enfermeros reveló que los temas considerados básicos estaban relacionados a las situaciones que exigen una toma de decisión, rapidez y destreza bajo estrés o atención de una población específica, lo que refuerza la importancia de la capacitación en esa área.<br>A atuação do enfermeiro na área de atendimento pré-hospitalar (APH) pressupõe a aquisição de competências específicas. Os objetivos deste estudo foram verificar a opinião dos enfermeiros sobre conhecimentos teóricos e habilidades de enfermagem necessários para o exercício em APH e analisá-la de acordo com a prática clínica. Neste estudo descritivo, a opinião dos enfermeiros dos serviços públicos de APH do Município de São Paulo foi coletada por meio de questionário, e os dados da prática clínica em formulário. A ressuscitação cardiopulmonar foi mais citada como conhecimento básico (84%) e o procedimento mais freqüente foi a oxigenoterapia (15,5%). A análise das opiniões dos enfermeiros revelou que os temas considerados básicos relacionaram-se às situações que exigem tomada de decisão, prontidão e destreza sob estresse, ou atendimento de uma população específica, o que reforça a importância da capacitação nessa área

Arabidopsis CLAVATA1 and CLAVATA2 receptors contribute to Ralstonia solanacearum pathogenicity through a miR169-dependent pathway

Bacterial wilt caused by Ralstonia solanacearum is one of the most destructive bacterial plant diseases. Although many molecular determinants involved in R. solanacearum adaptation to hosts and pathogenesis have been described, host components required for disease establishment remain poorly characterized. Phenotypical analysis of Arabidopsis mutants for leucine-rich repeat (LRR)-receptor-like proteins revealed that mutations in the CLAVATA1 (CLV1) and CLAVATA2 (CLV2) genes confer enhanced disease resistance to bacterial wilt. We further investigated the underlying mechanisms using genetic, transcriptomic and molecular approaches. The enhanced resistance of both clv1 and clv2 mutants to the bacteria did not require the well characterized CLV signalling modules involved in shoot meristem homeostasis, and was conditioned by neither salicylic acid nor ethylene defence-related hormones. Gene expression microarray analysis performed on clv1 and clv2 revealed deregulation of genes encoding nuclear transcription factor Y subunit alpha (NF-YA) transcription factors whose post-transcriptional regulation is known to involve microRNAs from the miR169 family. Both clv mutants showed a defect in miR169 accumulation. Conversely, overexpression of miR169 abrogated the resistance phenotype of clv mutants. We propose that CLV1 and CLV2, two receptors involved in CLV3 perception during plant development, contribute to bacterial wilt through a signalling pathway involving the miR169/NF-YA module