1.Clinical distribution and drug resistance analysis of 415 strains of Klebsiella pneumonia
International Journal of Laboratory Medicine 2014;(22):3076-3077
Objective To analyze the distribution and drug resistance of the isolated strains of K lebsiella pneumonia .Methods The strains of K lebsiella pneumonia were isolated from specimens from clinical departments ,and the drug resistance was tested . The results were analyzed .Results There were 415 strains of K lebsiella pneumonia were isolated .The isolated strains distributed mainly in Department of Neurosurgery (36 .1% ) ,Department of Respiratory Medicine (27 .7% ) ,and ICU (16 .9% ) .74 .7% of the strains were isolated from sputum specimens .30 .0% of the isolated strains were ESBLs positive .The drug resistance rates of K leb‐siella pneumonia to meropenem and imipenem were both low to 0 .5% .Conclusion Monitoring the drug resistance of K lebsiella pneumonia is very important to guide the treatment .
2.Effects of continuous light exposure on muscle fiber remodeling and lipid metabolism in mice
Haohao ZHANG ; Lu ZHENG ; Guijun QIN ; Saifei WANG ; Jing WU ; Qian QIN ; Ang LI ; Xiao HAO ; Hongfei JI
Chinese Journal of Endocrinology and Metabolism 2021;37(3):221-227
Objective:To observe the effects of continuous light exposure on skeletal muscle fiber type transformation and lipid metabolism, and to explore its internal relationship.Methods:Mice were randomly divided into normal light group and 24-hour continuous light group by random number table. The serum and skeletal muscle lipid content and urine 6-sulfatoxymelatonin(6-SML)level were detected by ELISA. The expression of circadian clock and lipid metabolism related genes mRNA were observed by realtime PCR. The muscle fiber type and lipid deposition were evaluated by tissue immunofluorescence as well as oil red O staining.Results:Compared with the normal light group, the level of 6-SML in urine at night decreased( P<0.05), and the expression level and rhythm of brain and muscle ARNT-like protein 1(Bmal1), circadian locomotor output cycles protein kaput(Clock), and period 2(Per2)mRNA in the skeletal muscle changed in continuous light group. In addition, the body weight, blood lipid, free fatty acid, and triglyceride contents of skeletal muscle in continuous light group increased significantly( P<0.05 or P<0.01), the expression of carnitine palmitoyltransferase 1b (Cpt1b)mRNA, the key enzyme of fatty acid oxidation, decreased significantly( P<0.05), while the expression of stearoyl-CoA desaturase(Scd1)mRNA, a lipid synthesis related gene, increased significantly( P<0.01). Further immunofluorescence analysis showed that the proportion of slow muscle fibers decreased and that of fast muscle fibers increased in continuous light group(both P<0.05). Conclusion:The process of ectopic deposition of lipid in skeletal muscle in mice induced by continuous light exposure may be related to the remodeling of skeletal muscle fibers.
3.Activation of PXR causes drug interactions with Paxlovid in transgenic mice.
Saifei LEI ; Alice GUO ; Jie LU ; Qian QI ; Aaron S DEVANATHAN ; Junjie ZHU ; Xiaochao MA
Acta Pharmaceutica Sinica B 2023;13(11):4502-4510
Paxlovid is a nirmatrelvir (NMV) and ritonavir (RTV) co-packaged medication used for the treatment of coronavirus disease 2019 (COVID-19). The active component of Paxlovid is NMV and RTV is a pharmacokinetic booster. Our work aimed to investigate the drug/herb-drug interactions associated with Paxlovid and provide mechanism-based guidance for the clinical use of Paxlovid. By using recombinant human cytochrome P450s (CYPs), we confirmed that CYP3A4 and 3A5 are the major enzymes responsible for NMV metabolism. The role of CYP3A in Paxlovid metabolism were further verified in Cyp3a-null mice, which showed that the deficiency of CYP3A significantly suppressed the metabolism of NMV and RTV. Pregnane X receptor (PXR) is a ligand-dependent transcription factor that upregulates CYP3A4/5 expression. We next explored the impact of drug- and herb-mediated PXR activation on Paxlovid metabolism in a transgenic mouse model expressing human PXR and CYP3A4/5. We found that PXR activation increased CYP3A4/5 expression, accelerated NMV metabolism, and reduced the systemic exposure of NMV. In summary, our work demonstrated that PXR activation can cause drug interactions with Paxlovid, suggesting that PXR-activating drugs and herbs should be used cautiously in COVID-19 patients receiving Paxlovid.