Dissemination of three coliphages in chicken’s organism

Fundação para a Ciência e a Tecnologia (FCT

Obtenção de chips de caju por osmose seguida de fritura.

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In vivo toxicity study of phage lysate in chickens

1. Bacteriophage (phage) crude lysate of Gram-negative bacteria often contains bacterial debris, including lipopolysaccharides found in the outer membrane of the cell wall, which are potentially toxic. 2. In this study, an in vivo evaluation of the toxicity of a suspension of three phages to control pathogenic Escherichia coli strains in poultry was performed. 3. Eighteen commercial layers, 7 weeks old, were intramuscularly injected with phage lysate (8.21x10 4 Endotoxin Units/dose). The control group was injected with sterile Luria Bertani (LB) broth. 4. Bird prostration and decrease in body weight gain and water intake per gram of body weight were observed only on the day of the inoculation in the challenged group. Over the following 6 d, no differences were observed in the chickens’ activity. 5. These results support the view that phage crude lysate carrying endotoxins are not toxic for chickens.Fundação para a Ciência e a Tecnologia (FCT

Uso de RMN no Estado Estacionário para Aumento de Sensibilidade de Análises Químicas.

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Revisiting phage therapy: new applications for old resources

The success of phage therapy is dependent on the development of strategies able to overcome the limitations of bacteriophages as therapeutic agents, the creation of an adequate regulatory framework, the implementation of safety protocols, and the acceptance by the general public. Many approaches have been proposed to circumvent phages intrinsic limitations but none have proved to be completely satisfactory. In this review we present the major hurdles of phage therapy and the solutions proposed to circumvent them. A thorough discussion on the advantages and drawbacks of these solutions is provided and special attention is given to genetic modification of phages as an achievable strategy to shape bacteriophages to exhibit desirable biological properties.The authors thank the FCT Strategic Project PEst-OE/EQB/LA0023/2013 and the Project 'BioHealth - Biotechnology and Bioengineering approaches to improve health quality, Ref. NORTE-07-0124-FEDER-000027' cofunded by the Programa Operacional Regional do Norte (ON.2 - O Novo Norte), QREN, and FEDER. F.L.N. also acknowledges the FCT for grant SFRH/BD/86462/2012

Metodologia de medida da difusividade térmica por RMN-CWFP.

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In vivo efficiency evaluation of a phage cocktail in controlling severe colibacillosis in confined conditions and experimental poultry houses

Infections caused by avian pathogenic Escherichia coli (APEC) cause important economic losses to poultry industry. The studies presented herein, aimed at investigating the in vivo performance of a cocktail of three phages in treating severe respiratory E. coli infections in experimentally contaminated birds and naturally infected flocks. Three lytic coliphages, phi F78E (Myoviridae), phi F258E (Siphoviridae) and phi F61E (Myoviridae) were combined in a 5.0 × 107 PFU/ml cocktail to be used in naturally APEC infected flocks (refractive to antibiotherapy). Experimentally infected birds were treated with phi F78E at two different titres (107 PFU/ml and 109 PFU/ml). Phage administration was performed orally and by spray, in a single application. The morbidity, mortality and pathology scores were compared with control birds not receiving phage therapy. The results revealed that the success of phage therapy in experimental rooms was dosage dependent, being 107 PFU/ml not enough to treat the infected chickens whereas a concentration of 109 PFU/ml of phi F78E allowed a decrease of 25% and 43% in chickens’ mortality and morbidity, respectively. In the large scale experiments, the results obtained showed a remarkable efficacy of the low titre phage cocktail (107 PFU/ml) in decreasing the flocks’ mortality to levels below 0.5% in no more than 3 weeks, with no recidivism. Based on the results we can conclude that phage treatment is a valuable alternative to control APEC infections in poultry

Medida Rápida e Simultânea dos Tempos de Relaxação Longitudinal e Transversal por RMN-CWFP.

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