RESUMO
Bronchopulmonary dysplasia(BPD)is a common chronic lung disease in preterm infants, which seriously affects the survival rate of preterm infants.Its etiology and pathogenesis are complex and unclear.Therefore, the prevention, diagnosis and treatment of BPD have become an important clinical issue.With the rapid development of high-throughput sequencing technology, it has been found that the respiratory tract flora can act as an early biomarker of BPD risk, and then judge the progress of BPD and the timing of treatment, so as to achieve the purpose of early treatment and improved prognosis.This article mainly describes the changes in the diversity and abundance of the respiratory tract flora of BPD in premature infants, the mechanism of action of the flora on BPD, and the future treatment methods based on the flora.
RESUMO
OBJECTIVE:To establish a method for determining the plasma concentration of paeoniflorin and phillyrin and phar-macokinetic study before and after intragastric administration of Qianliean granules. METHODS:LC-MS/MS method was adopted. The column was Waters C18 with mobile phase consisted of acetonitrile(A)-2 mmol/L ammonium acetate(containing 0.05% formic acid)(B)(0-9 min:15%A→50%A;9-11 min:50%A→90%A;11-17 min:90%A;17-19 min:90%A→15%A;19-20 min:15%A),at the flow rate of 0.6 ml/min;column temperature was 35 ℃ and the volume was 20 μl;quantitative ions were paeoniflorin m/z 525.2 → m/z 449.0,phillyrin m/z 552.3 → m/z 355.3. 7 SD male rats were docked to collect blood 0.5 ml from angular vein 0.25,0.5,0.75,1,1.5,2,3,4,6,8,10,12,24 h after administration Qianliean granule solution 1 g(medicinal materials)/kg to determine the blood concentration of drugs. DAS 2.1.1 software was employed to calculate pharmacokinetic parameters. RE-SULTS:The linear range of paeoniflorin and phillyri were 5.0-2500.0 μg/L(r=0.9979)and 2.0-2000.0 μg/L(r=0.9982),re-spectively;RSD of precision test was less than 5.5%(n=5);the method recovery were 96.0%-104.0% and 92.0%-107.0%,the extration recovery were 71.4%-83.5% and 81.5%-92.3% and RSD of stability test was less than 5.0%(n=3). The pharmacokinet-ic parameters of paeoniflorin and phillyrin were as follows as t1/2 of (2.206 ± 0.631) and (1.355 ± 0.317) h;cmax of (1504.069 ± 620.885) and (79.043 ± 15.568)μg/L;tmax of (1.000 ± 0.250) and (1.214 ± 0.267) h;AUC0-24 h of (4897.645 ± 2207.577) and (263.475±54.795)μg·h/L;CL of(5.025±2.773)and(76.253±13.986)L/(h·kg). CONCLUSIONS:The method is highly sensi-tive,exclusive,simple,accurate and reliable,and can be applied to study the pharmacokinetic characteristics of paeoniflorin and phillyrin in rats in vivo.