Objective To investigate whether Heshouwuyin can delay the aging of Leydig cells in rat testis through DNA methyltransferase 1(DNMT1).Methods Totally 40 male Wistar rats were randomly divided into 4 groups,with 10 rats in each group.Immunohistochemistry was used to detect the expression levels of DNMT1 in testis tissue of rats.Testosterone content in serum of rats in each group was detected by ELISA test.A rat Leydig cell aging model was established by free radical oxidative damage.DNMT1 was knocked down by lentivirus in Leydig cells,and the cell senescence status and the testosterone content and testosterone synthesis key enzyme 3β-hydroxysteroid dehydrogenase(3β-HSD),cytochrome P450 family member 11A1(CYP11A1)content secreted by cells were detected by β-galactosidase(β-GAL)staining,immunofluorescenct staining and ELISA.Results Compared with the young control group(YCG),the expression of P16 protein and the positive rate of β-GAL in the testis tissue of rats in the natural aging group(NAG)increased significantly,and the expression of DNMT1 and serum testosterone levels decreased(P＜0.05).However,after Heshouwuyin intervention,the expression of P16 protein and the positive rate of β-GAL in the testis of aging rats were reduced,and DNMT1 expression and the serum testosterone levels increased(P＜0.05).The same trend was observed in Leydig cells.Knockdown of DNMT1 in Leydig cells,β-GAL positivity and P16 protein expression increased significantly,and testosterone secretion and testosterone synthesis key enzymes 3β-HSD,CYP11A1 content from Leydig cells decreased significantly,compared with the normal control group(NCG)(P＜0.05).When Heshouwuyin was added,the above phenomenon was improved.Conclusion Heshouwuyin can delay the aging of rat Leydig cells through DNMT1.

Aim To explore the mechanism of Bushen Tongfu decoction(BSTF)improving the learning and memory ability of APP/PS1 mice.Methods The APP/PS1 mice were administered by BSTF for eight weeks.The spatial learning and memory ability of all mice were detected by Morris water maze.The changes in the intestinal microbiota and gut metabolites of mice were detected by 16S rDNA and LC-MS/MS technolo-gy.Results Compared with the model group,the es-cape latency and swimming path in BSTF-H,BSTF-M and BSTF-L groups were shortened and the times of target crossings after removing the platform increased significantly(P＜0.01).The 16S rDNA results showed that BSTF could increase the abundance of beneficial bacteria of Firmicutes and reduce the abun-dance of harmful bacteria of Bacteroidota in APP/PS1 mice.A total of 25 differential metabolites were identi-fied by LC-MS/MS,including sphingolipid metabo-lism,lysine metabolism and tyrosine metabolism.KEGG enrichment analysis showed that the therapeutic effect of BSTF was mainly through inflammation-related signaling pathways such as NF-κB pathways and Apelin pathways.Conclusions The mechanism of BSTF im-proving the learning and memory ability of APP/PS1 mice may be related to the improvement of intestinal flora composition,the effect of sphingolipid metabo-lism,lysine metabolism and tyrosine metabolism and the regulation of inflammation-related signaling path-ways such as NF-κB and Apelin pathways.

Heart failure with preserved ejection fraction(HFpEF)may be a main form of heart failure,with a high mortality and an increasing incidence,which is a significant problem in cardiovascular disease.Although some important advancements in HFpEF has been made in recent years,its pathogenesis remains unclear,and the prognosis and mortality of patients have not significantly improved.Due to a large number of complications and complex pathological mechanism of HFpEF,and traditional treatment medicines of heart failure cannot effectively improve the prognosis of HFpEF patients,it is still lack of accurate diagnostic methods and effective clinical treatment strategies.Exploring and developing effective diagnostic and therapeutic approaches are of great clinical significance.This review summarizes the progress and future research direction in the diagnosis and treatment of HFpEF.

Objective: To development the prognostic nomogram for malignant pleural mesothelioma (MPM). Methods: Two hundred and ten patients pathologically confirmed as MPM were enrolled in this retrospective study from 2007 to 2020 in the People's Hospital of Chuxiong Yi Autonomous Prefecture, the First and Third Affiliated Hospital of Kunming Medical University, and divided into training (n=112) and test (n=98) sets according to the admission time. The observation factors included demography, symptoms, history, clinical score and stage, blood cell and biochemistry, tumor markers, pathology and treatment. The Cox proportional risk model was used to analyze the prognostic factors of 112 patients in the training set. According to the results of multivariate Cox regression analysis, the prognostic prediction nomogram was established. C-Index and calibration curve were used to evaluate the model's discrimination and consistency in raining and test sets, respectively. Patients were stratified according to the median risk score of nomogram in the training set. Log rank test was performed to compare the survival differences between the high and low risk groups in the two sets. Results: The median overall survival (OS) of 210 MPM patients was 384 days (IQR=472 days), and the 6-month, 1-year, 2-year, and 3-year survival rates were 75.7%, 52.6%, 19.7%, and 13.0%, respectively. Cox multivariate regression analysis showed that residence (HR=2.127, 95% CI: 1.154-3.920), serum albumin (HR=1.583, 95% CI: 1.017-2.464), clinical stage (stage Ⅳ: HR=3.073, 95% CI: 1.366-6.910) and the chemotherapy (HR=0.476, 95% CI: 0.292-0.777) were independent prognostic factors for MPM patients. The C-index of the nomogram established based on the results of Cox multivariate regression analysis in the training and test sets were 0.662 and 0.613, respectively. Calibration curves for both the training and test sets showed moderate consistency between the predicted and actual survival probabilities of MPM patients at 6 months, 1 year, and 2 years. The low-risk group had better outcomes than the high-risk group in both training (P=0.001) and test (P=0.003) sets. Conclusion: The survival prediction nomogram established based on routine clinical indicators of MPM patients provides a reliable tool for prognostic prediction and risk stratification.
Humans ; Mesothelioma, Malignant ; Prognosis ; Nomograms ; Retrospective Studies ; Proportional Hazards Models

A sensitive and simple high-performance liquid chromatographic tandem mass spectrometric (LC-MS/MS) method for the determination of verapamil and norverapamil in human plasma was established and utilized in a pharmacokinetic study in healthy patients. Protein was precipitated by methanol in plasma samples, and the analytes and internal standard were separated on an Agilent Zorbax Eclipse C₁₈ column (50 mm×4.6 mm, 5 μm) with a gradient procedure using methanol-acetonitrile (50∶50) as the organic phase and 0.1% formic acid - 5% acetonitrile - 10 mmol·L^-1 ammonium formate solution as the mobile phase at flow rate of 0.5 mL·min^-1. Electrospray ionization (ESI) and multiple reaction monitoring (MRM) detection modes were used for quantitative detection of verapamil, norverapamil and verapamil-d₆ (IS). In the mode of multiple reaction monitoring of positive-ions, the monitoring ion pairs of verapamil, norverapamil and the verapamil-d₆ were m/z 445.0→165.2, m/z 441.0→165.2 and m/z 461.1→165.2, respectively. The quantitative lower limit (LLOQ) for the determination of verapamil and norverapamil concentrations in human plasma can reach 0.1 ng·mL^-1 in this assay. The calibration curve concentration ranged from 0.1 to 50 ng·mL^-1 with high linearity (r² > 0.997). The matrix effect of verapamil and norverapamil was 99.2%-100% and 101%-102%, respectively. The recovery of verapamil and norverapamil was 86.8%-95.9% and 87.4%-94.8%, respectively. This method has good specificity and high sensitivity. The determination of the verapamil and norverapamil was not subject to the matrix effect and stable extraction recovery was achieved in this assay. This method could be used to determine the concentration of verapamil and norverapamil in human plasma and suitable for human pharmacokinetic studies after approved by ethics committee.

A sensitive and efficient liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for quantitative determination of diflucortolone in rabbit plasma after dermal administration of diflucortolone valerate cream to rabbits. After extraction with ethyl acetate, the chromatographic separation was performed on Zorbax Eclipse XDB-C18 (50 mm×4.6 mm, 5 μm) with a gradient mobile phase consisting of 50% acetonitrile-50% methanol and 0.1% formic acid-5% methanol-5 mmol·L^-1 ammonium formate at a flow rate of 0.35 mL·min^-1. The quantitative analysis was carried out using multiple reaction monitoring (MRM) at specific ion transitions of m/z [M+H]⁺ 395.2→m/z 355.2 for diflucortolone and m/z [M+H]⁺ 258.1→m/z 120.9 for ethoxyphenylethylamine (internal standard) in positive ion mode with electrospray ionization (ESI) source. This validated LC-MS/MS method had a linearity over the concentration range of 0.01-10 ng·mL^-1 with the lower limit of quantification (LLOQ) at 0.01 ng·mL^-1. At level of LLOQ, the inter and intra-assay precision (RSD) were no greater than 9.82% and 11.0%, respectively. The main pharmacokinetic parameters of the diflucortolone including t_max, C_max, AUC_{0-72 h}, and t_1/2 were as follows: (6.33±1.21) h, (0.168±0.080 0) ng·mL^-1, (3.15±0.834) h·ng·mL^-1, (32.0±17.4) h. The method was validated in the pharmacokinetic study of diflucortolone in rabbit following dermal administration of diflucortolone valerate cream at dose of 0.01 g·cm^-2. In this study, the program of animal testing had been approved by Committee on the management and usage of experimental animal in the Evaluation Company of Innovative Drug, Tianjin Institute of Pharmaceutical Research.

A LC-MS/MS method for quantification of norfloxacin in human plasma had been developed. This method was applied to the pharmacokinetics study of norfloxacin in the human. The plasma sample was precipitated by methanol and ciprofloxacin was used as the internal standard (IS). Chromatographic separation was performed on a Symmetry® C₁₈ column(100 mm×4.6 mm, 5 μm). Mobile phase contains 0.3% formic acid and 5% methanol in deionized water at a flow rate of 0.45 mL·min^-1. Norfloxacin and ciprofloxacin (IS) were ionized with an ESI source and operated in positive ion mode. The detected ions were m/z 320.3→302.1 (norfloxacin), m/z 332.3→314.1 (ciprofloxacin). This LC-MS/MS method yielded a linearity over the range of 10-1 000 ng·mL^-1 with the lower limit of quantitation (LLOQ) of 10 ng·mL^-1. The intra and inter-assay precisions (RSD%) were within the range of 2.64%-7.23% and the accuracy (RE%) was less than ±5.00%. The pharmacokinetic parameters t_max, C_max, AUC_0-t, and t_1/2 were 1.28±0.364 h, 627±171 ng·mL^-1, 2 938±850 h·ng·mL^-1, and 6.01±1.36 h, respectively. This LC-MS /MS method was proven simple, sensitive, rapid and suitable for pharmacokinetics study of norfloxacin in the human and Approved by the Medical Ethics Committee of Liuzhou Workers' Hospital.

A simple and sensitive method was developed for quantitation of obeticholic acid in rat plasma with liquid chromatography-tandem mass spectrometry (LC-MS/MS). After liquid-liquid extraction by methyl tert-butyl ether, the chromatographic separation was carried out on an ACE Excel 2 Super C18 column (50 mm×2.1 mm ID, 1.7 μm) with a gradient mobile phase consisting of acetonitrile and 2 mmol·L^-1 ammonium formate at a flow rate of 0.2 mL·min^-1. The quantitation analysis was performed using multiple reaction monitoring (MRM) at the specific ion transitions of m/z 418.9[M-H]^-→401.2 for obeticholic acid and m/z 469.0[M-H]^-→ 425.2 for glycyrrhetinic acid (internal standard) in the negative ion mode with electrospray ionization (ESI) source. This validated LC-MS/MS method yielded a good linearity over the range of 5 -5 000 ng·mL^-1 with the lower limit of quantitation (LLOQ) of 5 ng·mL^-1. The intra and inter-assay precisions (RSD) were all less than 9.82% and the accuracy (RE) was within ±6.90%. The extraction recovery of obeticholic acid was from 85.4% to 88.5%, and the matrix effect of obeticholic acid ranged from 78.9% to 82.5%. Stability test suggest that obeticholic acid in rat plasma was stable for 24 h on workbench, up to 1 month at -70℃, and after three cycles of freeze-thaw. Extracted samples were stable for more than 24 h in an auto-sampler at 6℃. The precision was less than 7.25%, and the accuracy was within ±11.2%, after being diluted 10 times by blank rat plasma. The method has been successfully applied to a pharmacokinetic study of obeticholic acid in rats following oral administration at the dose of 2.5 mg·kg^-1.

A pre-column derivatization method combined with UHPLC-MS/MS was developed for the simultaneous determination of salidroside and tyrosol in Beagle dog plasma. After protein precipitation by acetonitrile, the liquid supernatant was treated with dansyl chloride under dark conditions at 60℃ for 30 min, and then, the sample solution was extracted using methyl tertiary butyl ether. The multiple reaction monitoring in positive ion mode was used for MS detection of the tested analytes with the specific ion transitions of m/z 534.2→372.0 for salidroside derivative, m/z 372.0→171.0 for tyrosol derivative and m/z 506.0→171.0 for arbutin derivative. The chromatograph separation was achieved on an ACQUITY UPLC^® BEH C₁₈ column (100 mm×2.1 mm, 1.7 μm) with a gradient mobile phase consisting of acetonitrile (0.1% formic acid)-water (10% acetonitrile, 0.1% formic acid) for 9 min. The assay showed a good linearity over the range of 0.02/0.1-20/10 μmol·L^-1 with a lower limit of quantitation of 0.02 and 0.1 μmol·L^-1 for salidroside and tyrosol in dog plasma, respectively. The intra-and inter-day precisions were all less than 8.68%, and the accuracy was within ±11.4%. The established method with a high sensitivity, good specificity and reliability was appropriate for simultaneous determination of salidroside and tyrosol in dog plasma and successfully applied to a pharmacokinetic study after intragastric administration of salidroside to Beagle dogs.

Bentysrepinine (Y101), a derivative of phenylalanine dipeptide, is a novel drug candidate for the treatment of hepatitis B virus (HBV) infection. Our previous preclinical pharmacokinetic study showed that its in vivo absorption and distribution characteristics were probably related to transmembrane transport after Y101 was administered intragastically in rats. In this study, Caco-2 and MDCK-MDR1 cell models were used to investigate interactions between Y101 and P-gp through the apparent permeation coefficient (P_app) and efflux ratio (R_E); the results showed that Y101 was a substrate of P-gp. In addition, gene-transfected cell models, HEK293-hOATP1B1, HEK293-hOATP2B1 and CHO-PEPT1 were used to evaluate the affinity to OATP1B1,