The Status of Carbapenem Resistance in Cystic Fibrosis: A Systematic Review and Meta-Analysis.

Background: Antibiotic resistance in cystic fibrosis (CF) is a well-known phenomenon. However, the comprehensive epidemiological impact of antibiotic resistance in CF is not clearly documented. So, this meta-analysis evaluated the proportion rates of carbapenem resistance (imipenem, meropenem, and doripenem) in CF based on publication date (1979-2000, 2001-2010, and 2011-2021), continents, pathogens, and antimicrobial susceptibility testing (AST). Methods: We searched studies in PubMed, Scopus, and Web of Science (until April 2021). Statistical analyses were conducted using STATA software (version 14.0). Results: The 110 studies included in the analysis were performed in 25 countries and investigated 13,324 pathogens associated with CF. The overall proportion of imipenem, meropenem, and doripenem resistance in CF were 43% (95% CI 36-49), 48% (95% CI 40-57), 28% (95% CI 23-33), and 45% (95% CI 32-59), respectively. Our meta-analysis showed that trends of imipenem, meropenem, and doripenem-resistance had gradual decreases over time (1979-2021). This could be due to the limited clinical effectiveness of these antibiotics to treat CF cases over time. Among the opportunistic pathogens associated with CF, the highest carbapenem resistance rates were shown in Stenotrophomonas maltophilia, Burkholderia spp., Pseudomonas aeruginosa, and Staphylococcus aureus. The highest and lowest carbapenem resistance rates among P. aeruginosa in CF patients were shown against meropenem (23%) and doripenem (39%). Conclusions: We showed that trends of carbapenem resistance had decreased over time (1979-2021). This could be due to the limited clinical effectiveness of these antibiotics to treat CF cases over time. Plans should be directed to fight biofilm-associated infections and prevent the emergence of mutational resistance. Systematic surveillance for carbapenemase-producing pathogens in CF by molecular surveillance is necessitated.

Polymorphism detection of promoter region of IFN-γ and IL-2 genes and their association with productive traits in Mazandaran native breeder fowls.

To identify polymorphism in interferon gamma (IFN-γ) and interleukin-2 (IL-2) genes, blood samples were collected from 380 breeder hens of the Mazandaran native fowls breeding station. DNA extraction was performed through a modified saltingout method and fragments of 670 and 659 bp from the promoter regions of IFN-γ and IL-2 genes were amplified by using specific primers, respectively. Following genotyping in the IFN-γ gene using the Tsp509I restriction enzyme, two alleles of A and G with the frequencies of 0.55 and 0.45 and three genotypes of AA, AG and GG were observed with the frequencies of 0.32, 0.46 and 0.22, respectively. For the IL-2 gene, two alleles of A and G were also detected using the MnlI restriction enzyme with the frequencies of 0.58 and 0.42 and three genotypes of AA, AG and GG with the frequencies of 0.33, 0.50 and 0.17, respectively. Statistical analysis revealed significant associations between IL-2 gene single-nucleotide polymorphism and productive traits including the average egg weight (EW) at 345-375 days of age, egg number (EN) at 345-375 days of age and body weight (BW) at 8weeks of age traits (P<0.05). Further, in a mean comparison analysis, there were also significant differences between different genotypes of the IL-2 gene in average EWat 28 and 30weeks of age, in which AG genotypes showed higher performance. Additionally, for the IFN-γ gene, a significant difference was found between the genotypes in average EW at 28 weeks of age trait. Therefore, it can be concluded that the above-mentioned polymorphisms could be considered as the pivotal geneticmakers to improveMazandaran native fowl breeding programmes to achieve the optimum performance in productive traits more efficiently.