To observe the clinical efficacy and safety of different doses of poractant alfa injection combined with mechanical ventilation in the treatment of children with very low body mass and neonatal respiratory distress syndrome (NRDS).

According to cohort method, children with very low body mass and NRDS were divided into control group and treatment group. On basis of mechanical ventilation, control group were treated with 100 mg·kg^-1 poractant alfa injection; treatment group were treated with 200 mg·kg^-1 poractant alfa injection. The clinical curative effect, recovery related indexes, ventilation function, blood gas indexes [partial pressure of carbon dioxide (PaCO₂), pH, partial pressure of oxygen (PaO₂)], inflammatory factors [interleukin (IL)-6, C-reactive protein (CRP)] and complications in the two groups were compared, and the safety was evaluated.

There were 43 cases in control group and 43 cases in treatment group. After treatment, there was significant difference in total response rate between treatment group and control group [93.02% (40 cases/43 cases) vs 76.74% (33 cases/43 cases), P<0.05]. After treatment, injection frequencies in treatment group and control group were (1.02±0.15) and (1.47±0.50) times, oxygen inhalation time was (90.45±7.31) and (116.72±10.24) h, mechanical ventilation time were (81.27±6.81) and (99.69±9.05) h, hospitalization time was (12.15±2.07) and (16.29±2.53) d, fraction of inspired oxygen were (36.39±4.07)% and (40.54±5.13)%, positive end-expiratory pressure were (3.64±0.53) and (4.05±0.69) cmH₂O, peak inspiratory pressure were (20.12±1.45) and (22.69±1.62) cmH₂O, PaCO₂ were (31.45±4.21) and (37.72±5.06) mmHg, pH were 7.36±0.30 and 7.21±0.27, PaO₂ were (83.46±6.45) and (78.58±5.93) mmHg, levels of serum IL-6 were (36.21±4.03) and (54.83±5.69) ng·L^-1, CRP levels were (8.03±2.11) and (11.28±3.06) mg·L^-1, and the differences were statistically significant (all P<0.05). There was significant difference in incidence of complications between treatment group and control group [9.31% (4 cases/43 cases) vs 25.57% (11 cases/43 cases), P<0.05]. The adverse drug reactions were mainly on rash, gastrointestinal dysfunction and irritability in treatment group, while which in control group were rash and gastrointestinal dysfunction. There was no significant difference in total incidence of adverse drug reactions between treatment group and control group [9.30% (4 cases/43 cases) vs 6.98% (3 cases/43 cases), P>0.05].

200 mg·kg^-1 poractant alfa injection combined with mechanical ventilation can promote the recovery of children with very low body mass and NRDS, improve ventilation function and blood gas indexes, alleviate inflammatory response and reduce complications, and the safety is good.

To establish a ultra-high performance liquid chromatography-tandem mass spectrometer (UPLC-MS/MS) method for determining the concentration of sotagliflozin in rat plasma and apply it to pharmacokinetic studies in rats.

Electrospray negative ion multi-reaction ion detection was used. Chromatographic column: EXT-C₁₈ (2.1 mm×100.0 mm, 2.7 μm); column temperature: 45 ℃; mobile phase: 5 mmol·L^-1 ammonium acetate aqueous solution-acetonitrile; flow rate: 0.35 mL·min^-1; ion pairs: sotagliflozin m/z 483.3→315.1, dapagliflozin m/z 467.4→329.2; injection volume: 6 μL, plasma samples were processed using methyl tert-butyl ether liquid-liquid extraction. Six male SD rats were administered a single oral dose of sogliflozin at 40 mg·kg^-1, and detected the concentration of sogliflozin in plasma. Pharmacokinetic parameters were calculated using Drug And Statistics (DAS) 2.1.1.

Sotagliflozin showed good linearity within the range of 5-2 000 ng·mL^-1, with intra-day and inter-day precision both less than 15%. The recovery rate, matrix effect, and stability were all within the specified range. Pharmacokinetic parameters: C_max was (3 716.67±568.28) ng·mL^-1, t_max was (1.00±0.32) h, t_1/2 was (2.28±0.45) h, AUC_0-t was (1.70×10⁴±2 075.87) ng·mL^-1·h.

This study established a method for determining the concentration of sotagliflozin in rat plasma, which is characterized by high sensitivity, rapid detection, and good repeatability. It is suitable for the determination of sotagliflozin concentration in plasma and pharmacokinetic studies.

To evaluate the pharmacokinetics (PK) and pharmacodynamics (PD) of propofol injectable emulsion, and to assess the bioequivalence of test and reference formulations in healthy Chinese adult volunteers.

Thirty-two healthy Chinese adult volunteers were recruited and randomly assigned to a fasting. single-dose, two-period and double-crossover study. Propofol was given to eligible subjects at a speed of 30 μg·kg^-1·min^-1 for 30 min. The concentration of propofol in plasma was determined by avalidated high performance liquid chromatography-tandem mass spectrometery (HPLC-MS/MS) method. The PK parameters of the two preparations were calculated. Bispectral index (BIS) was measured to calculate the PD parameters of two formulations. Adverse events during the trial were recorded.

Thirty-one volunteers were included in the pharmacokinetic parameter set. The mean values of PK parameters of test andreference formulations were as follows: C_max were (660.87±110.25) and (683.13±125.75)ng·mL^-1; AUC_0-t were (473.50±86.03) and (478.40±80.25)h·ng·mL^-1; AUC_0-∞ were (500.45±96.49) and (507.84±88.00)h·ng·mL^-1; t_max were 0.47(0.25,0.53) and 0.50(0.40, 0.54)h; t_1/2 were (2.97±1.74) and (3.08±1.82)h. Thirty-one volunteers were included in the bioequivalence set. The 90% confidence intervals (CI) for the geometric mean ratios of C_max, AUC_0-t, AUC_0-∞ were 92.64%-101.39%, 96.43%-101.00%, 95.67%-100.70%, respectively. The mean values of PD parameters of test and reference formulations were as follows: BIS_min were (75.94±13.66) and (74.39±12.32); BIS_{AUC 0-60 min} were 5 569.85±182.78 and 5 575.68±166.19; T-BIS_min were 23.00 and 29.00 min, respectively. There were no serious adverse events.

Two formulations of propofol injectable emulsion were bioequivalent and both of them exhibited good safety.

To investigate the effect and mechanism of methyl oxofulnonone A (META) on high glucose (HG)-induced H9c2 cell injury.

H9c2 cells were divided into control group (normal culture), model group (55 mmol·L^-1 glucose) and experimental -L, -M, -H groups (55 mmol·L^-1 glucose+12.5, 25.0, 50.0 μmol·L^-1 META). Cell viability was detected by cell counting kit-8; intracellular reactive oxygen species (ROS) level was detected by DCFH-DA fluorescent probe; intracellular adenosine triphosphate (ATP) content was detected by luciferase; and autophagy-related protein expression was detected by Western blotting.

The optical density values of 72-hour cells in the control group, model group and experimental -M, -H groups were 0.91±0.03, 0.61±0.01, 0.69±0.02 and 0.72±0.03; the ROS levels were (40.75±1.53)%, (43.73±1.30)%, (30.87±1.27)% and (28.28±1.43)%; the ATP contents were (8.16±0.71), (4.03±0.29), (5.29±0.31) and (5.83±0.31) nmol·mg^-1; the relative expression levels of autophagy-related gene 5 protein were 1.05±0.06, 1.46±0.09, 0.98±0.11 and 0.89±0.09; the relative expression levels of ubiquitin-binding protein were 1.05±0.10, 0.55±0.13, 0.89±0.04 and 0.98±0.04; the ratios of microtubule-associated protein 1 light chain 3 Ⅱ/Ⅰ protein were 1.09±0.09, 1.82±0.05, 1.67±0.29 and 1.09±0.15, respectively. Among the above indicators, there were statistically significant differences between the model group and the control and experimental -M, -H groups (P<0.05, P<0.01).

META significantly ameliorates H9c2 cardiomyocyte damage caused by high glucose, ameliorates oxidative stress, protects mitochondrial respiration and inhibits autophagy.

To establish a method for determining the concentration of contezolid in human cerebro spinal fluid (CSF) using ultra high performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS).

Linezolid as the internal standard (IS) and acetonitrile as the protein precipitant. Waters ACQUITY UPLC^® BEH C₁₈ (2.1 mm×50.0 mm, 1.7 μm) chromatographic column was used for separation, with a mobile phase of 0.1% formic acid aqueous solution-0.1% formic acid acetonitrile solution, gradient elution method, flow rate was 0.4 mL·min^-1, column temperature was 40 ℃, automatic sampler temperature was 10 ℃, the analysis time was 4 minutes. Electrospray ion source, positive ion mode, and multi-reaction monitoring scanning mode were used. The monitoring and analysis ion pairs for contezolid were m/z 409.15→269.14, and the monitoring ion pairs for linezolid were m/z 338.14→195.10. The specificity, standard curve and lower limit of quantification (LLOQ), precision and recovery rate, matrix effect, residual effect, dilution effect and stability of the method were investigated.

The endogenous substances in CSF do not interfere with the determination of the analyte contezolid and the internal standard linezolid, and the method has good specificity. Satisfactory linearity was observed within the concentration range of 20-5 000 ng·mL^-1 for contezolid in CSF, the calibration curve was y=8.97×10^-4x+1.95×10^-2 (r=0.999 1), and the LLOQ was 20 ng·mL^-1. Precision of the intra-batch and inter-batch relative standard deviation (RSD)<15%, and the extraction recovery were 90.96%-98.71%. The average normalized matrix effect factor of the quality control CSF sample were 94.39%-100.25%. The RSD of dilution effect<15%. The CSF samples of contezolid were stored at room temperature, in the automatic sampler for 72 hours, -20 ℃ and -80 ℃ for 90 days, and subjected to repeated freezing and thawing three times, were stable with all of which the RSD<10%.

This method is high sensitivity, rapid, simple and accurate, which is very suitable for the therapeutic drug monitoring of contezolid in human CSF.

To investigate whether O6-methylguanine-DNA methyltransferase (MGMT) interference combined with temozolomide (TMZ) could enhance the therapeutic effect of temozolomide on human drug-resistant melanoma cells A375/TMZ.

A375/TMZ cells were randomly divided into 4 groups, control group (normal culture), MGMTsiRNA group (200 nmol·L^-1 MGMTsiRNA), experimental group (1 600 μmol·L^-1 TMZ) and combined group (transfection of MGMTsiRNA followed by addition of 1 600 μmol·L^-1 TMZ). After 24 h of culture, the proliferation of cells in each group was analyzed by cell counting kit-8 method. Western blotting was used to detect the expression levels of poly ADP-ribose polymerase (PARP), cleaved PARP(cleaved-PARP), DNA-dependent protein kinase catalytic subunit(DNA-PKcs) and nuclear factor kappa-B(NF-κB) proteins in the cells. The expression and distribution of NF-κB proteins in the cells were detected by immunofluorescence.

Cell inhibition rates of control, MGMTsiRNA, experimental and combined groups were 0, (3.45±1.53)%, (51.24±2.73)% and (70.69±4.48)%; the relative expression levels of PARP protein were 0.45±0.08, 0.47±0.06, 0.33±0.04, 0.14±0.03; the relative expression levels of the cleaved-PARP protein were 0.01±0.02、0.01±0.01、0.18±0.03 and 0.36±0.04; the relative expression levels of DNA-PKcs protein were 0.09±0.03, 0.07±0.02, 0.32±0.02 and 0.39±0.04; the relative expression levels of NF-κB protein were 0.35±0.04, 0.36±0.05, 0.20±0.02 and 0.15±0.02. Compared with experimental group or control group, the differences of above indexes were all statistically significant (all P<0.05). Immunofluorescence analysis showed that the average fluorescence intensity of NF-κB in control group, MGMTsiRNA group, experimental group and combined group were (5.26±1.05)%, (7.58±1.18)%, (10.56±1.99)% and (15.47±2.61)%; and compared with the cells in control group and MGMTsiRNA group, combined group showed NF-κB was significantly increased in the nucleus of tumor cells, and the difference was statistically significant (all P<0.01).

MGMTsiRNA combined with TMZ further promotes proliferation inhibition and apoptosis of drug-resistant melanoma A375/TMZ cells by TMZ.

To explore the brain damage of SD rats under different time points of hypobaric hypoxia exposure.

A rat high-altitube cerebral edema (HACE) model was constructed by simulating an altitude of 6 000 m in a hypobaric hypoxia animal experimental chamber. Thirty-six SD male rats were randomly divided into the control group and the hypobaric hypoxia exposure 3, 7 and 14 d groups, with 9 rats in each group. Except for the control group, the rats in each group were continuously exposed to hypobaric hypoxia for 3, 7, and 14 d. At the end of the modeling period, serum was collected by blood sampling via the abdominal aorta, and brain tissue samples were taken. The wet-to-dry ratio (W/D) of brain tissue was calculated, and the levels of relevant oxidative enzymes in serum and brain tissue were measured. The expression levels of hypoxia-inducible factor-1α (HIF-1α) and aquaporin 4 (AQP4) mRNAs in brain tissue were detected by real-time fluorescence quantitative polymerase chain reaction.

The W/D of brain tissues in the control group and the group exposed to hypobaric hypoxia for 3, 7 and 14 d were 4.46±0.12, 4.98±0.16, 5.07±0.18 and 4.95±0.07; the superoxide dismutase contents were (111.86±2.45), (90.73±1.48), (79.64±2.56) and (55.33±1.45) U·g^-1; the glutathione contents were (126.91±5.18), (125.26±1.53), (56.20±2.17) and (122.73±1.78) μg·mL^-1; the malondialdehyde contents were (230.94±2.00), (362.65±3.28), (407.34±3.47) and (237.50±1.59) nmol·g^-1; the relative expression levels of HIF-1α mRNA were 1.00±0, 2.99±0.49, 4.72±0.49 and 1.91±0.28; the relative expression levels of AQP4 mRNA were 1.00±0, 2.62±0.34, 8.38±0.84 and 5.27±0.42, respectively. Statistically significant differences were found between the above indexes in the 3, 7 and 14 d of hypobaric hypoxia exposure group compared with the control group (P<0.05, P<0.01).

Different time of hypobaric hypoxia exposure can up-regulate the expression of AQPs proteins in HACE rats and cause the disruption of the blood-brain barrier, and the HACE model constructed in the hypobaric hypoxia chamber with 6 000 m intervention for 7 d was more stable.

To investigate the effect of epifriedelanol (Epi) on gene expression of P-glycoprotein (P-gp) in human colorectal adenocarcinoma cell line LS174T and its mechanism.

LS174T cells were divided into control group and experimental -L, -M, -H groups. Experimental -L, -M, -H groups were treated with 5, 10, 20 μmol·L^-1 Epi, respectively. Control group was treated with 0.1% dimethyl sulfoxide. Polymerase chain reaction was used to detect the mRNA expression level of P-gp. The effect of Epi on multidrug resistance protein 1 (MDR1/P-gp) luciferase activity was investigated by pregnane X receptor (PXR)-MDR1/P-gp dual luciferase reporter gene assay. In addition, Western Blot was used to detect the protein expression level of P-gp and the nuclear factor-κB (NF-κB) pathway related proteins.

The relative expression levels of P-gp mRNA in experimental -M, -H groups and control group were 52.24±5.19, 23.00±3.52 and 100.00±9.00; the relative expression levels of P-gp protein were 86.37±9.96, 74.85±15.92 and 100.00±12.91; the relative activities P-gp luciferase were 230.19±41.32, 203.10±52.84 and 279.67±19.20; the relative expression levels of p65 (RelA/p65) in nucleus were 132.36±23.93, 145.96±25.15 and 100.00±10.88; the relative expression levels of phosphorylation NF-κB inhibits protein kinase α/β (p-IKKα/β) in cytoplasm were 184.00±54.82, 290.10±49.59 and 100.00±15.34; the relative expression levels of phosphorylated NF-κB inhibitory protein α (p-IκBα) in cytoplasm were 125.73±18.77, 133.69±20.25 and 100.00±8.12; the relative expression levels of IκBα in cytoplasm were 78.36±14.83, 70.44±14.57 and 100.00±22.82, respectively. The above indexes of experimental -M and experimental -H groups were compared with control group, and the differences were statistically significant (P<0.05, P<0.01, P<0.001).

Epi can down-regulate the gene expression of P-gp in human colorectal adenocarcinoma cell line LS174T, and the mechanism may be related to activation of NF-κB and suppression of PXR.