案例分析与情景模拟在急诊护理教学的效果

目的探讨分案例分析法结合情景模拟法在急诊护理学生教学中的应用价值。方法以2016年10月-2017年10月本院纳入的46例急诊科实习护士为例展开研究,以教学方式的不同将46例急诊科实习护士分成观察组(n=23,接受案例分析法结合情景模拟法教学)和对照组(n=23,接受传统法教学),教学结束后对比分析两组急诊科实习护士的学习情况以及评判性思维能力。结果教学结束后,经考核发现,观察组实操成绩以及理论成绩均高于对照组(P <0.05);观察组寻求真相、求知欲、系统化能力以及分析能力等评判性思维能力均高于对照组(P <0.05)。结论在急诊护理学生教学中应用案例分析法结合情景模拟法进行教学,有利于急诊科实习护士掌握理论知识以及实操知识,同时还可以提高其评判性思维能力,可实现有效教学。     

Dose optimization of moxifloxacin and linezolid against tuberculosis using mathematical modeling and simulation

Introduction

There is an urgent need for new anti-tuberculosis (TB) drugs and optimization of current TB treatment. Moxifloxacin and linezolid are valuable options for the treatment of drug-resistant TB; however, it is crucial to find a dose at which these drugs not only show high efficacy but also suppress the development of further drug resistance.

Population Pharmacokinetics and Dosing Simulations of Ceftazidime in Chinese Neonates

An accurate dosage determination is required in neonates when antibiotics are used. The adult data cannot be simply extrapolated to the pediatric population due to significant individual differences. We aimed to identify factors impacting ceftazidime exposure in neonates and to provide drug dosing guidance to clinicians. Forty-three neonates aged less than 60 days with proven or suspected infections were enrolled in this study. After intravenous administration, blood samples were collected, and plasma ceftazidime concentration was determined using a HPLC method. Pharmacokinetic data were fitted using a nonlinear mixed-effects model approach. One-compartmental model could nicely characterize the ceftazidime in vivo behavior. The covariate test found that the postmenstrual age (day) was strongly associated with systemic drug clearance (L/h), and the effect of body weight (kg) was identified as the covariate on distribution volume (L). Compared with the base model, the addition of covariates improved the goodness-of-fit of the final model. Model validation (bootstrap, visual predictive check, and prediction-corrected visual predictive check) suggested a robust and reliable pharmacokinetic model was developed. Personalized dosage regimens were provided based on model simulations. The intravenous dose should be adjusted according to postmenstrual age, body weight, and minimum inhibitory concentration.     

A Mathematical Model and Experimental Verification of Optimal Nozzle Diameter in Needle-Free Injection

Needle-free injection (NFI), as an alternative drug delivery strategy, owns great potential. It is able to reduce complaints about needle phobia and avoid the occurring of accidental needle stick injuries. The nozzle diameter is inherently important in determining the injection dose, injection depth, and pain associated with NFIs. In this work, needle-free injectors with nozzle diameters of 0.17, 0.20, 0.30, 0.40, and 0.50 mm were studied in the simulation and experiment. This article optimizes the mathematical model for spring-powered NFI by considering the hydraulic loss due to the abrupt change in the nozzle exit area and the friction force between the piston and ampoule. We explore the dispersion pattern in gels with different nozzle diameters. Mice insulin injection was conducted to investigate the pharmacological effect of different injection methods. The experimental results show that there is the best dispersion effect and available injection depth while the nozzle diameter is 0.30 mm, which is in agreement with the result predicted by the mathematical model. Also, there is a satisfactory pharmacological effect on the mice insulin injection under the same injection condition. Undoubtedly, the mathematical model is capable of predicting the suitable nozzle diameter under the given conditions.     

Characterization of CYP2C Induction in Cryopreserved Human Hepatocytes and Its Application in the Prediction of the Clinical Consequences of the Induction

CYP2C enzymes play key roles in drug metabolism, and clinical drug-drug interactions caused by CYP2C induction have been reported. The aim of this study was to establish a method to predict the potency of CYP2C inductions considering the mechanism. We first investigated the relations of CYP2C induction with CYP3A4 or CYP2B6 induction in human hepatocytes after 48-h exposure with 19 inducers. The fold-induction values of CYP2C8 and CYP2C9 were well correlated with those of CYP3A4, whereas the inducers were separated into 2 groups showing different correlations with CYP2B6 induction for CYP2C8 and CYP2C9 induction. In the regression models established, the fold-induction values of CYP2C8 and CYP2C9 were well expressed as the functions of those of CYP3A4 and CYP2B6, while no such obvious correlation was observed for CYP2C19 induction. These results suggest that CYP2Cs are not simply coinduced with CYP3A4 and that CYP2C8 and CYP2C9 inductions are regulated by both pregnane X receptor and constitutive androstane receptor with different contributions. Finally, simple correlations were proposed using the experimental E_max values obtained and plasma concentrations of CYP2C9 substrates from the literature, and positive correlations were observed. These data provide methods to estimate the clinical impact of CYP2C9 induction from in vitro data.     

腹主动脉瘤计算机仿真研究进展

腹主动脉瘤(abdominal aortic aneurysm,AAA)是腹主动脉较常见的疾病,破裂之后致死率极高,因此,及时发现和评估AAA破裂的风险就具有重要意义。近年来随着医学影像、计算机及血流动力学等理论和技术的快速发展,利用计算机模拟技术对AAA进行仿真研究已成为研究的热点,其模拟的结果趋于人体真实的动脉瘤,并在揭示AAA的发生及演变的机制方面发挥了重要作用。本文介绍了AAA仿真研究的原理及模型分类,详细地阐述了瘤体形态、瘤壁的结构及属性、血液及血流的属性、腔内血栓等相关因素在仿真研究中的作用,并对其目前的进展及局限性予以综述。     

Modeling Clinical Outcomes in Prostate Cancer: Application and Validation of the Discrete Event Simulation Approach

Objectives

Treatment landscape in prostate cancer has changed dramatically with the emergence of new medicines in the past few years. The traditional survival partition model (SPM) cannot accurately predict long-term clinical outcomes because it is limited by its ability to capture the key consequences associated with this changing treatment paradigm. The objective of this study was to introduce and validate a discrete-event simulation (DES) model for prostate cancer.

Three-dimensional finite-element model of the human temporomandibular joint disc during prolonged clenching

In the temporomandibular joint (TMJ), overloading induced by prolonged clenching appears to be important in the cascade of events leading to disc displacement. In this study, the effect of disc displacement on joint stresses during prolonged clenching was studied. For this purpose, finite-element models of the TMJ, with and without disc displacement, were used. Muscle forces were used as a loading condition for stress analysis during a time-period of 10 min. The TMJ disc and connective tissue were characterized as a linear viscoelastic material. In the asymptomatic model, large stresses were found in the central and lateral part of the disc through clenching. In the retrodiscal tissue, stress relaxation occurred during the first 2 min of clenching. In the symptomatic model, large stresses were observed in the posterior part of the disc and in the retrodiscal tissue, and the stress level was kept constant through clenching. This indicates that during prolonged clenching the disc functions well in the asymptomatic joint, meanwhile the retrodiscal tissue in the symptomatic joint is subject to excessive stress. As this structure is less suitable for bearing large stresses, tissue damage may occur. In addition, storage of excessive strain energy might lead to breakage of the tissue.     

唇腭裂患者牙槽嵴数字化模型建立及分析的初步探讨

目的 通过三维激光扫描建立唇腭裂患者牙槽嵴的数字化模型，为唇腭裂患者的模型分析建立科学方法。方法 唇裂修复术前于全麻状态下对1例右侧完全性唇腭裂患者的上颌无牙颌制取模型，用激光扫描仪扫描，通过计算机逆向工程软件进行模型重建。结果 此法可在重建模型上设定测量参考点9个，并可测出各标志点间的距离；模型可切割后测量和计算。结论 激光扫描三维分析方法是分析唇腭裂患者牙槽嵴形态及方向改变的一种理想方法，应用此模型可量化分析唇腭裂患者随生长发育而变化的上颌牙槽嵴形态。