Effect of two lytic bacteriophages against multidrug-resistant and biofilm-forming Salmonella Gallinarum from poultry.

1. Salmonella Gallinarum (SG) infections cause fowl typhoid, which leads to important economic losses. Multidrug resistance (MDR) and the capacity for bacteria to form biofilms could play an important role in the persistence of SG in poultry flocks resulting in intermittent disease outbreaks. The aim of the following study was to assess the lytic activity of two new bacteriophages (Salmonella phages UPF_BP1 and UPF_BP2) against MDR and biofilm-forming SG. 2. Forty-six strains of SG, isolated in 2015, were characterised by antimicrobial resistance, biofilm formation profiles and susceptibility to two new bacteriophages. 3. Of these strains, 24% were multidrug resistant and more than 80% formed biofilm, with no statistical difference between incubation temperatures (42°C or 22°C). With regard to the lytic activity of the phages, 85% of strains were susceptible to at least one phage. Of these, 74% were lysed by both phages, including MDR and biofilm producing strains. 4. The use of salmonella phages UPF_BP1 and UPF_BP2 were shown to be promising alternatives for the biological control of fowl typhoid.

Preliminary validation of an instrument to assess social support and tuberculosis stigma in patients' families.

SETTING: Ribeirão Preto, São Paulo, Brazil. OBJECTIVE: To develop and validate a preliminary instrument for assessing social support and tuberculosis (TB) stigma in families of TB patients. DESIGN: A literature review on social support and TB stigma was used to generate the theoretical domains for the instrument. A focus group was then conducted with TB patients and their families to revise the domains. Reviewers were invited to judge the appropriateness of the items in the instrument. A cross-sectional survey was carried out among 110 family members to assess the factorial structure using principal component analysis and confirmatory factor analysis to assess construct validity. Reliability was assessed in terms of internal consistency using Cronbach's alpha. RESULTS: After semantic validation and a pilot study, 23 items were selected for the scale. Examination of the factorial structure of the 16 items that were factorable using principal component analysis led to the extraction of two factors. The 16-item instrument was assessed for construct validity with confirmatory factor analysis, which confirmed a model with four items for each dimension. CONCLUSION: The study analysed the psychometric properties of an instrument that is still in its preliminary stages. Other studies on a similar scale in the Brazilian setting are required.

Contexte : Ribeirão Preto, Brésil.Objectif : Elaborer et valider un instrument préliminaire afin d'évaluer le soutien social et la stigmatisation liée à la tuberculose (TB) dans les familles des patients.Schéma : Une revue de littérature relative au soutien social et à la stigmatisation liée à la TB a permis de générer les domaines théoriques de l'instrument. Un groupe focal a ensuite été réalisé avec des patients tuberculeux et leurs familles afin de revoir ces domaines. Les réviseurs ont été invités à juger le caractère approprié des éléments de l'instrument. Une enquête traversable auprès de 110 membres des familles a été effectuée afin d'évaluer la structures factorielles grâce à l'analyse du composant principal, avec une analyse du facteur de confirmation qui a permis de vérifier la validité de la construction. La fiabilité a été évaluée par la cohérence interne grâce au coefficient α de Cronbach.Résultats : Vingt-trois éléments composaient l'échelle après la validation sémantique et l'étude pilote. L'exploration de la structure factorielle des 16 items qui étaient favorables grâce à l'analyse du composant principal a extrait deux facteurs. L'instrument à 16 items a été évalué en termes de validité de la construction avec une analyse du facteur de confirmation qui a confirmé un modèle à quatre items pour chaque dimension.Conclusion : L'étude a démontré les propriétés psychométriques d'un instrument encore au stade préliminaire. Cette échelle doit être testée à travers d'autres études dans le contexte brésilien.

Marco de referencia: Ribeirão Preto, en Brasil.Objetivo: Validar una herramienta preliminar de evaluación del apoyo social y los estigmas relacionados con la tuberculosis (TB) en las familias de los pacientes.Método: Mediante una recensión bibliográfica sobre el apoyo social y los estigmas relacionados con la TB se definieron los dominios teóricos de la herramienta. Luego, en un grupo de opinión conformado por pacientes con diagnóstico de TB y sus familiares se verificaron los dominios. Se invitaron revisores con el objeto de juzgar la idoneidad de los elementos de la escala. Se llevó a cabo una encuesta transversal a 110 miembros de las familias de pacientes con el propósito de evaluar la estructura factorial, mediante un análisis de componentes principales y se aplicó un análisis factorial confirmatorio a fin de apreciar la validez conceptual de la escala. Mediante un análisis de la consistencia interna se examinó la fiabilidad de la escala con medición del coeficiente α de Cronbach.Resultados: Tras la validación semántica y el estudio preliminar, la escala estaba compuesta por 23 elementos. Se exploró la estructura factorial de los 16 elementos factorizables mediante el análisis de componentes principales y se extrajeron dos factores. La validez conceptual del instrumento de 16 elementos se verificó mediante un análisis factorial confirmatorio, el cual ratificó un modelo con cuatro elementos en cada dimensión.Conclusión: El estudio puso en evidencia las propiedades psicométricas de un instrumento que se encuentra en fases preliminares de desarrollo. Es necesario poner a prueba esta escala en otros estudios en el contexto del Brasil.

Acute renal failure potentiates methylmalonate-induced oxidative stress in brain and kidney of rats.

Tissue methylmalonic acid (MMA) accumulation is the biochemical hallmark of methylmalonic acidemia. The disease is clinically characterized by progressive neurological deterioration and kidney failure, whose pathophysiology is still unclear. In the present work we investigated the effects of acute MMA administration on various parameters of oxidative stress in cerebral cortex and kidney of young rats, as well as the influence of acute renal failure on MMA-elicited effects on these parameters. Acute renal failure was induced by gentamicin, an aminoglycoside antibiotic whose utilization over prolonged periods causes nephrotoxicity. The administration of gentamicin alone increased carbonyl content and inhibited superoxide dismutase (SOD) activity in cerebral cortex, as well as increased thiobarbituric acid-reactive substances (TBA-RS) and sulfhydryl levels and diminished glutathione peroxidase activity in kidney. On the other hand, MMA administration increased TBA-RS levels in cerebral cortex and decreased SOD activity in kidney. Furthermore, the simultaneous administration of MMA and gentamicin to the rats provoked an augment in TBA-RS levels and superoxide generation in cerebral cortex and in TBA-RS, carbonyl and sulfhydryl levels in kidney, while diminished SOD activity in both studied tissues. Finally, nitrate/nitrite content, reduced glutathione levels, 2',7'-dihydrodichlorofluorescein oxidation and catalase activity were not affected by this animal treatment in either tissue. In conclusion, our present data are in line with the hypothesis that MMA acts as a toxin in brain and kidney of rats and suggest that renal injury potentiates the toxicity of MMA on oxidative stress parameters in brain and peripheral tissues.

Bone remodelling analysis of a bovine femur for a veterinary implant design.

The response of bovine bone to the presence of an implant is analysed with the aim of simulating bone remodelling in a developing model of a polymeric intramedullary interlocking nail for veterinary use. A 3-D finite element model of the femur diaphysis is built based on computed tomography images and using a CAD-based modelling pipeline. The bone remodelling process after the surgery is analysed and compared with the healthy bone. The remodelling law assumes that bone adapts to the mechanical environment. For the analyses a consistent set of loads is determined for the bovine walk cycle. The remodelling results reproduce the morphologic features of bone and provide evidence of the difference on the bone behaviour when comparing metallic and polymeric nails. Our findings indicate that an intramedullary polymeric nail has the advantage over the metallic one of improving long-term bone healing and possibly avoiding the need of the implant removal.

Occurrence and characterization of Campylobacter in the Brazilian production and processing of broilers.

Twenty-two commercial broiler flocks and their carcasses, totaling 546 samples (450 collected from a poultry farm and 96 from a slaughterhouse), were surveyed for the presence of Campylobacter. The positive results for Campylobacter among the analyzed samples were homogeneous, yielding 81.8% for cecal droppings, 80.9% for feces, and 80.4% for cloacal swabs. Pre-enrichment and direct plating showed that 77.85% and 81.8% of cloacal swabs, respectively, were positive for Campylobacter compared to 99.0% and 97.9% of carcasses testing positive with the pre-enrichment and direct plating methods. The Campylobacter count averaged 7.0 log10 colony-forming units (CFU)/g in cecal droppings, 5.15 log10 CFU/carcass after defeathering, and 4.24 log10 CFU/carcass after chilling. The samples were identified by the API Campy system as Campylobacter jejuni subsp. jejuni (68.8%), Campylobacter coli (8.3%), Campylobacter jejuni subsp. doylei (6.3%), Campylobacter upsaliensis (4.2%), and Campylobacter fetus subsp. fetus (2.1%). The analyzed broiler flocks were positive for Campylobacter in 81.8% of the cases, thus characterizing the occurrence of this pathogen in a broiler-producing region in southern Brazil. These results highlight the importance of programs targeted at the reduction of Campylobacter in poultry products, in order to minimize the risks for consumers.