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Objective:To investigate the imaging quality of CBCT under different exposure parameters and the relationship between subjective and objective evaluation.Methods:CBCT scanners of 6 different suppliers[3D Accuitomo(Morita),i-mCAT(Kavo),5G(NewTom),Smart3D(Beijing Langshi),DCT Pro(Vatech),Vgi(NewTom)]were used to scan the spatial resolution models and head simulators under typical exposure conditions(different device with different tube voltage and current for exposure).The visibility of SedentexCT IQ phantom and anatomical structures generated by different CBCT scanners were compared.For objective evaluation,7 professional evaluators scored CBCT imaging qualities.For subjective evaluation,the resolution(LP/mm)of the images were com-pared among the devices.Results:No significant difference was found by 7 evaluators either intra or inter of the teams.By objective e-valuation,the score of NewTom 5G was 2,that of i-CAT was 5 and that of the others was 4.By subjective evaluation,the LP/mm of i-CAT was 1.8,that of Smart3D was 2.0 and that of the others was 1.0-1.7.The subjective evaluation of image quality obtained un-der different tube voltages and tube currents were significantly different.Conclusion:The subjective and objective evaluations of image quality are approximately consistent.The difference of the subjective image quality may be produced by the different tube voltage and current for exposure.
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Objective To explore the in vitro and in vivo antimicrobial activity of antipsychotic agent pimozide against Staphylococcus aureus(S.aureu).Methods The minimal inhibitory concentration(MIC)and minimum bactericidal concentration(MBC)of pimozide were determined by micro-dilution assay.Biofilm was cultured in 96-well cell culture plate,and the anti-biofilm activity of pimozide was detected by turbidimetry.The effect of pimozide on biofilm was further observed through laser confocal microscopy and SYTO9/PI staining.Combined antimicrobial effect of pimozide and other antimicrobial agents was detected by chessboard dilution method,and cytotoxicity of pimozide was detected by CCK-8 assay kit.A model of skin abscess was constructed,in vivo antimicrobial activity and toxicity of pimozide was tested.Results Pimozide showed significant dose-dependent antimicrobial activity against S.aureu,with a MIC of 8-16 μg/mL.It could significantly inhibit the formation of S.aureu biofilm and disperse the formed biofilm.The combination of pimozide and doxycycline has a synergistic antimicrobial effect in vitro,with a synergistic antimicrobial index of 0.5.It can significantly reduce the bacterial load in mouse abscess tissue in vivo,and reduce the live bacterial count from(8.25±0.13)lgarithmic value of CFU/abscess to(3.31± 0.81)logarithmic value of CFU/abscess(q=3.74,P＜0.05).The cytotoxicity of pimozide was extremely low,with a half inhibitory concentration of 64 μg/mL on cells.Conclusion Pimozide exhibits significant antimicrobial activity in vitro and in vivo with extremely low toxicity,thus is promising for the treatment of S.aureu-related local infection in psychiatric patients.
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OBJECTIVES@#Staphylococcus epidermidis (S. epidermidis) is a Gram-positive opportunistic pathogen that often causes hospital infections. With the abuse of antibiotics, the resistance of S. epidermidis gradually increases, and drug repurposing has become a research hotspot in the treating of refractory drug-resistant bacterial infections. This study aims to study the antimicrobial and antibiofilm effects of simeprevir, an antiviral hepatitis drug, on S. epidermidis in vitro.@*METHODS@#The micro-dilution assay was used to determine the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of simeprevir against S. epidermidis. Crystal violet staining assay was used to detect the biofilm inhibitory effect of simeprevir. The antimicrobial activity of simeprevir against S. epidermidis and its biofilm were explored by SYTO9/PI fluorescent staining. The combined effect between simeprevir and gentamycin was assessed by checkerboard assay and was confirmed by time-inhibition assay.@*RESULTS@#Simeprevir showed significant antimicrobial effects against S. epidermidis type strains and clinical isolates with the MIC and MBC at 2-16 μg/mL and 4-32 μg/mL, respectively. The antimicrobial effects of simeprevir were confirmed by SYTO9/PI staining. Simeprevir at MIC could significantly inhibit and break the biofilm on cover slides. Similarly, simeprevir also significantly inhibit the biofilm formation on the surface of urine catheters either in TSB [from (0.700±0.020) to (0.050±0.004)] (t=54.03, P<0.001), or horse serum [from (1.00±0.02) to (0.13±0.01)] (t=82.78, P<0.001). Synergistic antimicrobial effect was found between simeprevir and gentamycin against S. epidermidis with the fractional inhibitory concentration index of 0.5.@*CONCLUSIONS@#Simeprevir shows antimicrobial effect and anti-biofilm activities against S. epidermidis.
Subject(s)
Humans , Simeprevir , Antiviral Agents , Anti-Bacterial Agents/pharmacology , Cross Infection , GentamicinsABSTRACT
Bloodstream infection (BSI) is a systemic infectious disease. The incidence and mortality of BSI caused by carbapenem-resistant Klebsiella pneumoniae (CRKP) remain high, which brought severe challenges into clinical anti-infection treatment and enormous economic burdens for the patients. This article reviews the current research progress on risk factors of BSI caused by CRKP, hoping to provide reference for the early diagnosis and treatment of this disease.
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Exogenous calcium can enhance the resistance of certain plants to abiotic stress. However,the role of calcium insaltstressed honeysuckle is unclear. The study is aimed to investigate the effects of exogenous calcium on the biomass,chlorophyll content,gas exchange parameters and chlorophyll fluorescence of honeysuckle under salt stress. The results showed that the calcium-treated honeysuckle had better photochemical properties than the salt-stressed honeysuckle,such as PIABS,PItotal,which represents the overall activity of photosystemⅡ(PSⅡ),and related parameters for characterizing electron transport efficiency φP0,ψE0,φE0,σR,and φR are significantly improved. At the same time,the gas exchange parameters Gs,Ci,Trare also maintained at a high level. In summary,exogenous calcium protects the activity of PSⅡ,promotes the transmission of photosynthetic electrons,and maintains a high Ci,therefore enhances the resistance of honeysuckle under salt stress.