Clinical efficacy and safety of tigecycline based on therapeutic drug monitoring for carbapenem-resistant Gram-negative bacterium pneumonia in intensive care units.

BACKGROUND: We investigated the associations between the different doses of tigecycline, its efficacy and safety, and the role of tigecycline therapeutic drug monitoring for patients in the intensive care unit. METHODS: This study was a single-center cohort including patients infected with multidrug-resistant Acinetobacter baumannii (MDR-AB) and multidrug-resistant Klebsiella pneumoniae (MDR-KP) causing pulmonary infections. The steady-state plasma concentration after tigecycline administration was determined by High-Performance Liquid Chromatography (HPLC) in patients admitted to the ICU between October 2020 and December 2021. Multivariate analyses of tigecycline's clinical efficacy and safety were performed to control confounding factors. RESULTS: For this study, we included 45 patients and 45 blood samples to determine steady-state trough concentrations of tigecycline. All patients were divided into the High Dose (HD) and Standard Dose (SD) groups. The median trough concentration of tigecycline was 0.56 µg/mL in the HD group, which was higher than in the SD group (0,21 µg/mL), p = 0.000. There was no significant difference between the two groups of patients in terms of bacterial eradication rate, mortality rate, and clinical efficacy. Multiple regression analysis showed that the ICU days were correlated with mortality OR 1.030(1.005-1.056), p = 0.017. APACHE II was significantly associated with clinical efficacy OR 0.870(0.755-1.002), p = 0.045. The level of fibrinogen decline in the HD group was significantly higher than in the SD group (-3.05 ± 1.67 vs -1.75 ± 1.90), p = 0.038. We identified that age and tigecycline treatment duration influenced fibrinogen decline. CONCLUSIONS: Tigecycline plasma concentrations are significantly increased when using a high dose. However, the plasma concentration of tigecycline is not correlated with clinical efficacy and adverse reactions. Fibrinogen decline appears to be related to the patient's age and days of tigecycline. Large sample data are still needed to confirm the clinical guidance significance of tigecycline TDM.

Tetrahydroxystilbene glucoside protects against sodium azide-induced mitochondrial dysfunction in human neuroblastoma cells.

Objective: Mitochondrial dysfunction is evident in the early stage of Alzheimer's disease (AD). Therefore development of drugs that protect mitochondrial function is a promising strategy for AD. The present work was to investigate the effects of 2, 3, 5, 4'-Tetrahydroxystilbene-2-O-ß-d-glucosides (TSG) on a mitochondrial dysfunction cell model induced by sodium azide and elucidate the underlying mechanisms. Methods: Mitochondrial membrane potential (MMP) was detected by a fluorescence method. Cellular adenosine triphosphate (ATP) level was measured using a firefly luciferase-based kit. Reactive oxygen species (ROS) was detected using dichlorofluorescin diacetate (DCFH-DA). The expression levels of Bcl-2 and Bax were measured by Western blotting assay. Flow cytometry was utilized to measure apoptosis. Results: Pretreatment of TSG (25-200 µmol/L) for 24 h significantly elevated MMP and ATP content, reduced ROS level and Bax/Bcl-2 ratio, and inhibited apoptosis in SH-SY5Y cells exposed to sodium azide. Conclusion: These results suggest that TSG protects SH-SY5Y cells against sodium azide-induced mitochondrial dysfunction and apoptosis. These findings are helpful to understand the protective effect of TSG on mitochondria, which are involved in the early stage of AD.

[Difference in intestinal absorption of Wuzhuyu decoction between normal and migraine model rats].

To compare the intestinal absorption of Wuzhuyu decoction(WZYD) between normal rats and migraine model rats, and investigate the optimized WZYD from aspect of absorption. The rat single pass intestinal perfusion test(SPIP) was adopted for optimized sample and un-optimized sample in normal and migraine model rats induced by nitroglycerin and reserpine. The contents of 8 ingredients were determined by high performance liquid chromatography(HPLC), and 4 absorption parameters for each ingredient were calculated and compared: unit area absorption(Mper area), absorption rate constant(Ka), apparent coefficient(Papp) and relative absorption rate(RA). The results showed that there was a great difference between normal rats and model rats in the intestinal absorption of the same WZYD. As compared with normal rats, the absorption parameters of most ingredients in optimized sample were increased in migraine model rats induced by nitroglycerin; Similar phenomena were also found in migraine model rats induced by reserpine. However, the absorption parameters of most ingredients were decreased in un-optimized sample. Therefore, pathological model rats shall be used for effective ingredient recognition based on the correlation between intestinal absorption spectra and pharmacological effects. As compared with the un-optimized samples, the absorption of effective ingredients was faster, easier and more adequate in the optimized samples, revealing their mechanism on better efficacy from the aspect of absorption.

[Study on pharmacological ingredients of wuzhuyu tang treating migraine by correlating absorption ingredients in everted intestinal sac and pharmacodynamics].

Wuzhuyu Tang is a classical formula for treating migraine, but its' pharmacological ingredients is unclear yet. Present study employed the everted intestinal sac model to collect the absorption samples of 10 kinds of Wuzhuyu decoction, and then analyzed the contents of 9 ingredients in Wuzhuyu Tang and absorption samples quantitatively or semi-quantitatively by HPLC-DAD method. Reserpine was used to establish the mice model of migraine, and then the contents and activities of 5-hydroxytryptamine, noradrenaline, dopamine, nitric oxide and nitricoxide synthase in brain tissues and serums were determined respectively after oral administration of Wuzhuyu Tang. Using the partial least squares regression method to correlate the total absorption quantity of 9 ingredients and pharmacodynamics. The result shows that limocitrin-3-O-beta-D-glucoside, ginsenoside Rg1 and Rb1, rutaevine, limonin, evodiamine and rutaecarpine are the main ingredients influenced the effects in absorption samples in everted intestinal sacs, especially ginsenoside Rg1, rutaevine, evodiamine and rutaecarpine among them have obvious improving effects to most pharmacodynamics index, might be the pharmacological ingredients influenced the therapeutical effects of Wuzhuyu Tang treating migraine.