关节滑液检测在关节假体周围感染诊断中的研究进展

关节假体周围感染(periprosthetic joint infection,PJI)是人工关节置换术后可能发生的一种严重并发症,其导致的严重后果,无论对于医生还是患者来说,都很难接受。目前,由于多种不确定因素的存在,PJI诊断的准确性较低。传统的血清学检查、影像学检查有一定的价值,但是易受全身情况的影响,导致特异性不高。为了正确诊断关节假体周围感染,不同学科的研究人员采用各种不同的方法进行了大量的诊断研究,并取得了丰富的成果。近年来,关节滑液炎性标志物检测、分子生物学方法等被研究证实具有较高的敏感性和特异性。因此,关节滑液CRP、-防御素、白细胞酯酶、PCR技术等被广泛研究,期望能从中找到诊断关节假体周围感染的特异性指标,提高临床诊断的准确性。     

Computer-aided design of dry powder inhalers using computational fluid dynamics to assess performance

Dry powder inhalers (DPIs) are gaining popularity for the delivery of drugs. A cost effective and efficient delivery device is necessary. Developing new DPIs by modifying an existing device may be the simplest way to improve the performance of the devices. The aim of this research was to produce a new DPIs using computational fluid dynamics (CFD). The new DPIs took advantages of the Cyclohaler® and the Rotahaler®. We chose a combination of the capsule chamber of the Cyclohaler® and the mouthpiece and grid of the Rotahaler®. Computer-aided design models of the devices were created and evaluated using CFD. Prototype models were created and tested with the DPI dispersion experiments. The proposed model 3 device had a high turbulence with a good degree of deagglomeration in the CFD and the experiment data. The %fine particle fraction (FPF) was around 50% at 60?L/min. The mass median aerodynamic diameter was around 2.8–4?μm. The FPF were strongly correlated to the CFD-predicted turbulence and the mechanical impaction parameters. The drug retention in the capsule was only 5–7%. In summary, a simple modification of the Cyclohaler® and Rotahaler® could produce a better performing inhaler using the CFD-assisted design.     

脑脊液降钙素原及乳酸测定在早期诊断颅脑术后颅内感染的意义

目的研究降钙素原(PCT)及乳酸水平在早期诊断颅脑术后颅内感染的意义。方法颅脑术后颅内感染患者(n=20)和非颅内感染患者(n=20)的脑脊液和血液样本,检测脑脊液和血清PCT,脑脊液和血液乳酸水平等指标并进行统计分析。结果感染组脑脊液和血清PCT、乳酸水平较非感染组显著升高,差异有统计学意义(P0.05)。脑脊液PCT和乳酸水平诊断敏感性及特异性均较血清PCT和乳酸水平高。结论脑脊液PCT、乳酸在颅脑手术术后颅内感染的诊断中均有意义,其中脑脊液PCT较乳酸敏感性更高,临床应用价值更大。     

Use of a Checklist During Observation of a Simulated Cardiac Arrest Scenario Does Not Improve Time to CPR and Defibrillation Over Observation Alone for Subsequent Scenarios

Theory: Immersive simulation is a common mode of education for medical students. Observation of clinical simulations prior to participation is believed to be beneficial, though this is often a passive process. Active observation may be more beneficial. Hypotheses: The hypothesis tested in this study was that the active use of a simple checklist during observation of an immersive simulation would result in better participant performance in a subsequent scenario compared with passive observation alone. Methods: Medical students were randomized to either passive or active (with checklist) observation of an immersive simulation involving cardiac arrest prior to participating in their own simulation. Performance measures included time to cardiopulmonary resuscitation (CPR) and time to defibrillation and were compared between first and second scenarios as well as between passive and active observers. Results: Seventy-nine simulations involving 232 students were conducted. Mean time to CPR was 18 seconds (SD = 11.6) for those using the checklist and 24 seconds (SD = 15.8) for those who observed passively (M difference = 6 seconds), t(35) = 1.46, p =.153. Time to defibrillation was 94 seconds (SD = 26.4) for those using the checklist and 92 seconds (SD = 23.8) for those who observed passively (M difference = –2 seconds), t(38) =.21, p =.837. Time to CPR was 24 seconds (SD = 15.8) for passive observers and 31 seconds (SD = 21.0; M difference = 7 seconds), t(35) = 1.13, p =.265, for their first scenario counterparts. Time to CPR was 18 seconds (SD = 11.6) for active observers and 36 seconds (SD = 26.2; M difference = 18 seconds), t(24) = 2.81, p =.010, for their first scenario counterparts. Time to defibrillation was 92 seconds (SD = 23.8) for passive observers and 125 seconds (SD = 32.2; M difference = 33 seconds), t(33) = 3.63, p =.001, for their first scenario counterparts. Time to defibrillation was 94 seconds (SD = 26.4) for the active observers and 132 seconds (SD = 52.9; M difference = 38 seconds), t(28) =.46, p =.008, for their first scenario counterparts. Conclusions: Observation alone leads to improved performance in the management of a simulated cardiac arrest. The active use of a simple skills-based checklist during observation did not appear to improve performance over passive observation alone.     

Impact of bystander-performed ventilation on functional outcomes after cardiac arrest and factors associated with ventilation-only cardiopulmonary resuscitation: A large observational study

AimTo determine the effectiveness of ventilations in bystander cardiopulmonary resuscitation (BCPR) and to identify the factors associated with ventilation-only BCPR.MethodsFrom out-of-hospital cardiac arrest (OHCA) data prospectively collected from 2005 to 2011 in Japan, we extracted data for 210,134 bystander-witnessed OHCAs with complete datasets but no prehospital involvement of physician [no BCPR, 115,733; ventilation-only, 2093; compression-only, 61,075; and conventional (compressions+ventilations) BCPR, 31,233] and determined the factors associated with 1-month neurologically favourable survival using simple and multivariable logistic regression analyses. In 91,885 patients with known BCPR durations, we determined the factors associated with ventilation-only BCPR.ResultsThe rate of survival in the no BCPR, ventilation-only, compression-only and conventional group was 2.8%, 3.9%, 4.5% and 5.0%, respectively. After adjustment for other factors associated with outcomes, the survival rate in the ventilation-only group was higher than that in the no BCPR group (adjusted OR; 95% CI, 1.29; 1.01–1.63), but lower than that in the compression-only (0.76; 0.59–0.96) or conventional groups (0.70; 0.55–0.89). Conventional CPR had the highest OR for survival in almost all OHCA subgroups. The adjusted OR (95% CI) for survival after dividing BCPR into ventilation and compression components was 1.19 (1.11–1.27) and 1.60 (1.51–1.69), respectively. Older guidelines, female sex, younger patient age, bystander-initiated CPR without instruction, early BCPR and short BCPR duration were associated with ventilation-only BCPR.ConclusionsVentilation is a significant component of BCPR, but alone is less effective than compression in improving neurologically favourable survival after OHCAs.     

Association of the time to first epinephrine administration and outcomes in out-of-hospital cardiac arrest: SOS-KANTO 2012 study

Objective

This study assessed the association between the timing of first epinephrine administration (EA) and the neurological outcomes following out-of-hospital cardiac arrests (OHCAs) with both initial shockable and non-shockable rhythms.

Understanding the Influence of Nanocarrier-Mediated Brain Delivery on Therapeutic Performance Through Pharmacokinetic-Pharmacodynamic Modeling

This study aimed at evaluating how encapsulation in a regular nanocarrier (NC) (providing extended circulation time) or in a brain-targeting NC (providing prolonged circulation time and increased brain uptake) may influence the therapeutic index compared with the unformulated drug and to explore the key parameters affecting therapeutic performance using a model-based approach. Pharmacokinetic (PK) models were built with chosen PK parameters. For a scenario where central effect depends on area under the unbound brain concentration curve and peripheral toxicity relates to peak unbound plasma concentration, dose-effect and drug-side effect curves were constructed, and the therapeutic index was evaluated. Regular NC improved the therapeutic index compared with the unformulated drug due to reduced peripheral toxicity, while brain-targeting NC enhanced the therapeutic index by lowering peripheral toxicity and increasing central effect. Decreasing drug release rate or systemic clearance of NC with drug still encapsulated could increase the therapeutic index. Also, a drug with shorter half-life would therapeutically benefit more from a NC encapsulation. This work provides insights into how a NC for brain delivery should be optimized to maximize the therapeutic performance and is helpful to predict if and to what extent a drug with certain PK properties would obtain therapeutic benefit from nanoencapsulation.     

贵阳地区儿童重症社区获得性肺炎肺泡灌洗液病原及药敏分析

目的分析贵阳地区儿童重症社区获得性肺炎支气管肺泡灌洗液（BALF）病原学分布及耐药特点。方法收集989例重症社区获得性肺炎患儿临床资料，将支气管肺泡灌液采用支气管镜取出进行细菌培养、病毒以及肺炎支原体(MP)检测。结果（1）989例重症社区获得性肺炎患儿病原检出阳性716例，阳性率72.40%，细菌、病毒、支原体检出率分别33.27% （329例）、22.45%（222例）、31.45%（311例）。（2）细菌感染中的肺炎链球菌、金黄色葡萄球菌为最为常见的革兰阳性菌株(G+)；而肺炎克雷伯菌、大肠埃希菌为最为常见的革兰阴性菌株(G-)。培养菌株对青霉素类、红霉素、第1、2、3代头孢类抗生素有较高的耐药性，对头孢吡肟、拉氧头孢、哌拉西林、左氧氟沙星有较高的敏感性，对亚胺培南、万古霉素、利奈唑烷均无耐药发生。（3）病毒感染检出222例，其中呼吸道合胞病毒131例，腺病毒检测49例，流感病毒6例（A型2例，B型4例），副流感病毒36例（1型3例、2型4例、3型29例），病毒检出率以0～12月龄组最高，RSV、ADV感染主要集中在冬春季节。（4）肺炎支原体检出阳性率31.45%（311例），肺炎支原体检出率以3～5岁组最高。结论贵阳地区重症肺炎中肺炎克雷伯杆菌、肺炎链球菌、大肠埃希菌、金黄色葡萄球菌为重要的细菌病原。重要病毒为腺病毒和呼吸道病毒为主，1～12月龄组的病毒感染检出率比较高。