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ObjectiveTo study the virulence and biofilm inhibition effect of Fufang Huangbai Fluid Paint （FFHBFP） on methicillin-resistant Staphylococcus aureus （MRSA）， and to explore the antibacterial effect of FFHBFP on MRSA， which provides a theoretical basis and reference for clinical medication. MethodFirstly， the microdilution method and time–growth curve were used to determine the minimum inhibitory concentration （MIC） of FFHBFP and vancomycin （VAN） against MRSA and the effect on bacterial growth. The effects of FFHBFP and VAN on the inhibition of MRSA virulence factor lipase and restoration of hydrogen peroxide （H2O2） sensitivity were detected under sub-minimum inhibitory concentration （sub-MIC）. The inhibitory effect of FFHBFP and VAN on MRSA biofilm formation and maturation was detected by the microplate method. The morphological changes of mature biofilms before and after administration were observed under a scanning electron microscope （SEM）. Real-time polymerase chain reaction （Real-time PCR） was utilized to detect the effect of 50.600 g·L-1 concentration of FFHBFP on the expression of MRSA virulence gene crtM and biofilm-forming genes fnbA and icaA. Finally， molecular docking technology was used to predict the mechanism of potential antibacterial active ingredients of FFHBFP in inhibiting the virulence and biofilm of MRSA. ResultThe MIC of VAN was 2 mg·L-1， and VAN below 1 mg·L-1 exerted no effect on MRSA growth. The MIC of FFHBFP was not determined， while the 101.200-202.400 g·L-1 original solution inhibited MRSA growth. Compared with the blank group and the VAN group， sub-MIC （25.300-50.600 g·L-1 original solution） inhibited lipase and recovered MRSA sensitivity to H2O2 （P<0.01）. The results of the microplate method showed that FFHBFP （25.300-202.400 g·L-1 original solution） inhibited biofilm formation and maturation （P<0.05， P<0.01）. The SEM exhibited that FFHBFP made the structure of biofilm loose and the size of the bacteria varied. FFHBFP at 50.600 g·L-1 concentration can inhibit the expression of related virulence genes and biofilm-forming genes （P<0.05， P<0.01）， and molecular docking results also showed that the main antibacterial active ingredients in FFHBFP have good binding ability to the target. ConclusionFFHBFP that cannot directly kill MRSA exerts clinical efficacy by impairing virulence expression， biofilm formation， and other pathogenic properties.
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Objective::To explore the feasibility of the rapid identification system(MALDI-Biotyper System) of microorganisms for rapid identification of Pseudomonas aeruginosa and clinical isolation of Staphylococcus aureus. Method::Identification quality control and clinical isolation were conducted for drug resistance of S. aureus by microbial rapid identification system and broth dilution method. The scores of microbial rapid identification system were compared with the MIC value of broth dilution method. The drug resistance of P. aeruginosa was simultaneously identified to determine the accuracy and applicability of the rapid identification system of microorganisms. Result::The scores of the microbial rapid identification system showed that the score of sensitive quality control strain S. aureus was higher than 2.000, and the that of resistant strain of methicillin-resistant S. aureus(methicillin-resistant S. aureus, MRSA)was between 1.700 and 2.000.The score of clinically isolated S. aureus was between 1.700 and 2.000, which suggested the drug resistance and was consistent with the MIC value of the broth dilution method. At the same time, the systemic identification value of the P. aeruginosa, which is independent of the quality control sensitive strain, was greater than 2.000, showing sensitivity and it was a sensitive strain itself, which was consistent with the results. Conclusion::The microbial rapid identification system scoring method can be used for the rapid identification of the drug resistance of S. aureus and P. aeruginosa.
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Objective:To observe the effect of combination of Tanreqing injection(Tanreqing) and imipenem-cilastatin on extensively-drug resistant Pseudomonas aeruginosa (XDPA), and study the mechanism of the combination. Method:The minimum inhibitory concentrations (MICs) of Tanreqing and imipenem-cilastatin against planktonic XDPA strain isolated in clinic were determined by the broth microdilution method. The checkerboard method was used to evaluate the combination effect. The bacterial metabolic activity in mature biofilm was studied by microtiter-plate test. The destructive effect of combination drugs on dynamic biofilm was observed by using BioFlux system, and viable cells were examined by confocal laser scanning microscope (CLSM) after treatment. The scanning electron microscopy (SEM) was used for observing Pseudomonas aeruginosa and length measurement. Result:The MIC values of imipenem-cilastatin and Tanreqing were 512 mg·L-1 and more than 16 500 mg·L-1. The checkerboard analysis showed that Tanreqing could enhance the sensitivity of imipenem-cilastatin, while the combination drugs synergistically inhibited the growth of bacteria. Compared with the control group or the imipenem-cilastatin individual group, the combined drugs significantly reduced the amount of living bacteria in the biofilm (PPPConclusion:Tanreqing and imipenem-cilastatin synergistically inhibit the bacterial growth in planktonic and biofilm states, and destruct biofilms.
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Specificity of acupoints is one of the basic theories of the acupuncture and moxibustion sciences and is a very important basis to guide the clinical treatment of acupuncture and moxibustion. However, the scientific foundation of specificity of acupoints is still unclear, which has greatly restricted to the clinical effect improvement of acupuncture and moxibustion and has influenced to academic status of acupuncture and moxibustion sciences both in China and abroad. In this paper, the recent related researches are reviewed and then the key effects and mechanism that the tissue structure of acupoints can decide and affect specificity of acupoints-organs effects are analyzed and explored. It is held that acupuncture at the different tissue structure of the different depth in the different or the same acupoints will cause changes of varying qualities or degrees of visceral function because of stimulation of the different receptors in the different tissues followed by excitation of varying afferent nerve fibers.
Subject(s)
Animals , Humans , Acupuncture Points , Acupuncture Therapy , Treatment OutcomeABSTRACT
<p><b>AIM</b>There are many factors affecting hybridization in cDNA chip: DNA concentration immobilized on glass surface, spotting solution dissolving DNA, the concentration and purity of fluorescence-labeled probe, hybridization solution, hybridization temperature, hybridization time, Cy3- and Cy5-labeled probes, etc. In order to improve hybridization efficiency, tests were designed to optimize these factors.</p><p><b>METHODS</b>Factors are changed one by one. Optimal values are selected by comparing those of different groups.</p><p><b>RESULTS AND CONCLUSION</b>The efficient hybridization condition is as follows: 0.50 microgram.microL-1 DNA fragments resolved in 1 x Micro Spotting Solution (ArrayIt) hybridize with purified fluorescent probe in 0.5% SDS/10 x SSC at 42 degrees C.</p>