RESUMO
Rapid detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in infected patients is critical for infection control. Loop-mediated isothermal amplification (LAMP) has been demonstrated to be a rapid, simple, reliable, cost-effective and sensitive method to detect SARS-CoV-2 in a variety of samples in considerably less time than Real-Time PCR. In this study, we developed and optimized a rapid detection method for SARS-CoV-2 based on RT-LAMP method utilizing a specific primer set targeting the ORF1a gene and then examined its sensitivity and efficiency using a serially diluted viral RNA sample with a known concentration. Furthermore, the sensitivity of the RT-LAMP to detect SARS-CoV-2 in direct swab samples with varying Ct values were compared to a commercial molecular RT-qPCR based detection kit. According to our findings the optimal incubation time for RT-LAMP assay was 45 min. There was a complete agreement between RT-LAMP and RT-qPCR in diagnosing the viral genome in the diluted extracted RNA sample. However, it had a lower sensitivity (71%) to detect the viral genome in direct swab samples compared to RT-qPCR. In conclusion, due to its simplicity, rapidness, sensitivity, and specificity, RT-LAMP has tremendous potential as a point-of-care tool; nevertheless, more research is needed to utilize it for detecting SARS-CoV-2, particularly in direct swab samples.
Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , Técnicas de Laboratório Clínico/métodos , Teste para COVID-19 , Sensibilidade e Especificidade , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , RNA Viral/genéticaRESUMO
Gram-negative bacteria are infectious and life-threatening agents after hematopoietic stem cell transplantation (HSCT). So, this study aimed to investigate the prevalence of Pseudomonas aeruginosa and its antibiotic resistance in patients who have received Hematopoietic Stem-Cell Transplantation through a systematic review. The systematic search was done with key words; Pseudomonas aeruginosa, hematopoietic stem cell transplantation from 2000 to the end of July 2023 in Google Scholar and PubMed/Medline, Scopus, and Web of Science. Twelve studies were able to include our study. Quality assessment of studies was done by Appraisal tool for Cross-Sectional Studies. The most of the included studies were conducted as allo-HSCT. Infections such as respiratory infection, urinary infection and bacteremia have occurred. The rate of prevalence with P. aeruginosa has varied between 3 and 100%. The average age of the participants was between 1 and 74 years. The rate of prevalence of P. aeruginosa resistant to several drugs has been reported to be variable, ranging from 20 to 100%. The highest antibiotic resistance was reported against cefotetan (100%), and the lowest was related to tobramycin (1.8%) followed by amikacin, levofloxacin and ciprofloxacin with the prevalence of 16.6%. Our findings showed a high prevalence and antibiotic resistance rate of P. aeruginosa in Hematopoietic stem cell transplantation. Therefore, more serious health measures should be taken in patients after transplantation.
Assuntos
Farmacorresistência Bacteriana Múltipla , Transplante de Células-Tronco Hematopoéticas , Pseudomonas aeruginosa , Humanos , Antibacterianos/farmacologia , Estudos Transversais , Prevalência , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/isolamento & purificação , Infecções por Pseudomonas/epidemiologiaRESUMO
Background and Objectives: Biosurfactants are amphiphilic surface-active agents that mainly produced by various microorganisms. In this study, the anti-biofilm and inhibition of bacterial adhesion activities of two bacterial biosurfactants were investigated. Materials and Methods: After extraction and evaluation of Bacillus cereus and Serratia nematodiphila biosurfctants, inhibition of bacterial adhesion and anti-biofilm effects of them on Staphylococcus aureus and Pseudomonas aeruginosa were determined. Results: On average, the synergistic effect of two bacterial biosurfactants, caused about 60% decrease in adhesion and about 80% decrease in biofilm formation of S. aureus and P. aeruginosa. Conclusion: The results of this study showed that combination of B. cereus and S. nematodiphila biosurfactants would increase the potential of attachment inhibition and biofilm eradication with very low toxicity.