RESUMO
Salmonella enterica serovars are zoonotic bacterial that cause foodborne enteritis. Due to bacteria's antibiotic resistance, using bacteriophages for biocontrol and treatment is a new therapeutic approach. In this study, we isolated, characterized, and analyzed the genome of vB_SenS_TUMS_E19 (E19), a broad host range Salmonella bacteriophage, and evaluated the influence of E19 on liquid eggs infected with Salmonella enterica serovar Enteritidis. Transmission electron microscopy showed that the isolated bacteriophage had a siphovirus morphotype. E19 showed rapid adsorption (92% in 5 min), a short latent period (18 min), a large burst size (156 PFU per cell), and a broad host range against different Salmonella enterica serovars. Whole-genome sequencing analysis indicated that the isolated phage had a 42 813 bp long genome with 49.8% G + C content. Neither tRNA genes nor those associated with antibiotic resistance, virulence factors, or lysogenic formation were detected in the genome. The efficacy of E19 was evaluated in liquid eggs inoculated with S. Enteritidis at 4 and 25 °C, and results showed that it could effectively eradicate S. Enteritidis in just 30 min and prevented its growth up to 72 h. Our findings indicate that E19 can be an alternative to a preservative to control Salmonella in food samples and help prevent and treat salmonellosis.
RESUMO
Salmonella enteritidis is one of the most important foodborne pathogens that cause numerous outbreaks worldwide. Some strains of Salmonella have become progressively resistant to antibiotics, so they could represent a critical threat to public health and have led to the use of alternative therapeutic approaches like phage therapy. In this study, a lytic phage, vB_SenS_TUMS_E4 (E4), was isolated from poultry effluent and characterized to evaluate its potential and efficacy for bio-controlling S. enteritidis in foods. Transmission electron microscopy revealed that E4 has a siphovirus morphotype, with an isometric head and non-contractile tail. Determining the host range showed that this phage can effectively infect different motile as well as non-motile Salmonella enterica serovars. The biological characteristics of E4 showed that it has a short latent period of about 15 min and a large burst size of 287 PFU/cell, and is also significantly stable in a broad range of pHs and temperatures. The E4 whole genome contains 43,018 bp and encodes 60 coding sequences (CDSs) but no tRNA genes. Bioinformatics analysis revealed that the genome of E4 lacks any genes related to lysogeny behavior, antibiotic resistance, toxins, or virulence factors. The efficacy of phage E4 as a bio-control agent was assessed in various foodstuffs inoculated with S. enteritidis at 4°C and 25°C, and the resulting data indicated that it could eradicate S. enteritidis after a very short time of 15 min. The findings of the present study showed that E4 is a hopeful candidate as a bio-control agent against S. enteritidis and has the potential to be used in various foodstuffs.
Assuntos
Bacteriófagos , Fagos de Salmonella , Animais , Bacteriófagos/genética , Genoma Viral , Especificidade de Hospedeiro , Fagos de Salmonella/genética , Salmonella enteritidis/genéticaRESUMO
Pseudomonas aeruginosa is an opportunistic human pathogen that can lead to nosocomial infections which are in turn life threatening. The increase in antibiotic resistance, at an alarming rate, has resulted in a pressing need for alternative therapeutic approaches such as phage therapy, which hold promise according to several studies. This study featured the isolation and characterization of vB_PaeS_TUMS_P81, a new lytic Pseudomonas phage. The whole-genome sequencing indicated that it has a genome of 73,167 bp containing 93 predicted coding sequences. Genes involved in virulence or lysogeny pathway were nowhere to be found in the genome, so it is potentially safe when it comes to therapeutic applications. Genomic and phylogenetic analysis indicated that vB_PaeS_TUMS_P81 is a member of the genus Litunavirus, belonging to Schitoviridae family. The present study lays the groundwork for further research on treatment of P. aeruginosa infections.
Assuntos
Bacteriófagos , Fagos de Pseudomonas , Humanos , Bacteriófagos/genética , Pseudomonas aeruginosa/genética , Filogenia , Genômica , Fagos de Pseudomonas/genética , Genoma Viral/genéticaRESUMO
Pseudomonas aeruginosa is an opportunistic human pathogen that can cause life-threatening nosocomial infections. The alarming increase in antibiotic resistance has led to an urgent need for alternative therapeutic approaches, such as phage therapy, which has shown promising results in many studies. In this study, P121, a new lytic Pseudomonas phage, was isolated and characterized. Whole-genome sequencing showed that it has a genome of 73,001 bp that contains 91 predicted coding sequences. No genes involved in virulence or lysogeny were found in the genome, thus making it potentially safe for therapeutic applications. Genomic and phylogenetic analysis indicated that P121 is a member of the genus Litunavirus, family Schitoviridae. The present study provides some basic information for further research on treatment of P. aeruginosa infections.
Assuntos
Bacteriófagos , Fagos de Pseudomonas , Humanos , Bacteriófagos/genética , Pseudomonas aeruginosa , Filogenia , Genoma Viral , Genômica/métodos , Fagos de Pseudomonas/genéticaRESUMO
OBJECTIVE: With respect to the high cost and limited availability of albumin, its use must be restricted to indications strongly supported by solid scientific evidence. It was anticipated that with the implementation of the National Health Reform Plan (NHRP), the consumption of albumin would increase as the result of decreasing patients' out-of-pocket costs. This study aimed to evaluate the efficacy of protocol implementation on the rationalization of albumin use in surgery wards of Cancer Institute of Imam Khomeini Hospital Complex, Tehran, Iran. METHODS: This pre-post interventional study was conducted in 32-month phases from January to November 2014 in an Iranian University hospital. The first phase was before the implementation of NHRP, the second phase was after NHRP, and the last one was after the intervention. The first and second phases were conducted retrospectively. Data extraction was performed by a hospital pharmacist. During the third phase, the physicians were mandated to adhere to a local albumin protocol which had been prepared by clinical pharmacy service and approved by drug and therapeutic committee. Appropriateness of prescriptions regarding indication, dose, and duration based on local guideline was compared among groups. FINDINGS: Although hospital bed-days of care remained consistent among phases, albumin was prescribed for 40, 45, and 8 patients during first, second, and third phases, respectively. This shows about 80% reduction of drug prescriptions in the last phase. The mean duration/dose of albumin in inappropriate indications reduced significantly from 11.3 ± 8.2 days/24.7 ± 21.2 vials in the second phase to 2.6 ± 1.7 days/5.6 ± 3.5 vials in the third phase, respectively (P = 0.001 and P = 0.003). CONCLUSION: Interactive collaboration through guideline implementation seems effective in rationalizing the use of high-cost medications such as albumin.