轻度二氧化碳潴留慢性阻塞性肺疾病肺功能和CT的特征

目的探讨轻度CO₂潴留慢性阻塞性肺疾病人群的肺功及影像特征,为监测和治疗提供依据。 方法选择147例慢性阻塞性肺疾病急性加重期患者,分为非CO₂潴留组61例PaCO₂＝40～44.9 mmHg;轻度CO₂潴留组48例PaCO₂＝45～50 mmHg;呼吸衰竭组38例PaCO₂>50 mmHg,比较3组在肺功能和容积CT参数的异同。 结果轻度潴留组在肺功能参数如一秒率(FEV₁%pred)等和肺气肿参数如肺气肿平均密度(MED)、肺密度分布直方图中第15百分位点所对应的CT值(PD15)等,与呼吸衰竭组存在明显差异(P<0.05),与非潴留组无统计学差异(P>0.05)。spearman相关分析显示PaCO₂与FEV₁%Pred、FVC%pred呈中度负相关(r分别是-0.536,-0.576,P<0.001),与PD15和MED存在弱负相关(r＝-0.325,P＝0.002)。 结论轻度CO₂潴留COPD肺结构和功能特征与非潴留COPD相似;呼吸衰竭组COPD具有更严重的病理和肺功能损害;CO₂轻度潴留向Ⅱ型呼吸衰竭进展中,FEV₁%pred等肺功能指标联合PD15和MED影像参数从功能和结构上能更好地反应病情。     

机械通气的慢性阻塞性肺疾病急性加重期患者气道分泌物的细菌学特点

正慢性阻塞性肺疾病(chronic obstructive pulmonary disease,COPD)是我国慢性疾病重要组成部分之一,目前我国COPD患者约1亿人[1]。COPD急性加重期是导致COPD患者住院治疗、死亡的主要原因,感染是引起COPD急性加重的最常见原因,随病情逐渐进展,伴有呼吸衰竭发生,而机械通气是救治AECOPD合并呼吸衰竭的有效治疗措施,但是随之而来的是巨大的经济负担。另外气管插管的患者气道自然防御机制破坏,细菌更易进入下呼吸道并加重感染,气管插管是发生呼吸相关肺炎的危险因素之一[2-3]。因此对AECOPD患者行有创机械通气治疗细菌学及耐药性分析对于AECOPD感染的早期治疗极为重要。     

Percutaneous coronary intervention for acute coronary syndrome due to graft failure

Objectives : To describe clinical outcome after percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS) due to graft failure. Background : Limited data are available on outcome after PCI for graft failure‐induced ACS in the drug‐eluting stent (DES) era. Methods : Patients were identified who underwent PCI either with DES or BMS for ACS due to graft failure between January 2003 and December 2008. Follow‐up was performed at 1 year and April 2011. The primary endpoint was the composite of death, myocardial infarction (MI), or target vessel revascularization (TVR). Kaplan–Meier estimates were calculated at 1 and 5‐year follow‐up. Predictors were identified by backward selection in Cox proportional hazards models. Results : A total of 92 patients underwent PCI, of which 77 were treated with bare metal stents (BMS) and 15 with DES. Patient and procedural characteristics were similar in both groups. Mean follow‐up was 3.2 years. Five‐year composite event rate was 65.9% after BMS vs. 43.4% after DES implantation (P = 0.17). Individual endpoints were comparable in both groups. Recurrence of angina, hospitalization, and repeat interventions were similar. After multivariable adjustment, the use of DES was not associated with a significant reduction in the primary endpoint (HR = 0.44, 0.18–1.04, p = 0.06). Conclusion : In patients presenting with ACS due to acute graft failure, long‐term outcomes remain poor. In a nonrandomized comparison with BMS, DES use was not associated with significant improved long‐term clinical outcomes. © 2012 Wiley Periodicals, Inc.     

Hepatitis E virus re-infection accelerates hepatocellular carcinoma development and relapse in a patient with liver cirrhosis: A case report and review of literature

BACKGROUNDHepatitis E virus (HEV) superinfection is a suspected promoting factor for hepatocellular carcinoma (HCC) in patients with chronic hepatitis and cirrhosis. However, to date, very few cases of HEV-related HCC have been reported. Nevertheless, the role of HEV re-infection in cirrhotic liver without other chronic hepatitis infections has rarely been explored.CASE SUMMARYA 53-year-old male farmer was diagnosed with liver cirrhosis and splenomegaly in August 2016, accompanied with negative HEV-IgM and positive HEV-IgG. No evidence of hepatitis B virus or hepatitis C virus infection was found. Since then the patient was evaluated for liver function and viral parameters every 3 mo. In June 2017, the patient presented severe fatigue with whole body itching and was diagnosed with HCC. Afterwards this patient experienced quick HCC development, progression, relapse, and metastasis in the following 8 mo, and presented persistent dual positivity of HEV-IgM and HEV-IgG. This patient had a long history of smoking and alcohol consumption.CONCLUSIONThis unique case invokes the importance of HEV surveillance and treatment among cirrhotic patients, HCC cases, and blood donors.     

An Amphipathic Alpha-Helix Domain from Poliovirus 2C Protein Tubulate Lipid Vesicles

Positive-strand RNA viruses universally remodel host intracellular membranes to form membrane-bound viral replication complexes, where viral offspring RNAs are synthesized. In the majority of cases, viral replication proteins are targeted to and play critical roles in the modulation of the designated organelle membranes. Many viral replication proteins do not have transmembrane domains, but contain single or multiple amphipathic alpha-helices. It has been conventionally recognized that these helices serve as an anchor for viral replication protein to be associated with membranes. We report here that a peptide representing the amphipathic α-helix at the N-terminus of the poliovirus 2C protein not only binds to liposomes, but also remodels spherical liposomes into tubules. The membrane remodeling ability of this amphipathic alpha-helix is similar to that recognized in other amphipathic alpha-helices from cellular proteins involved in membrane remodeling, such as BAR domain proteins. Mutations affecting the hydrophobic face of the amphipathic alpha-helix severely compromised membrane remodeling of vesicles with physiologically relevant phospholipid composition. These mutations also affected the ability of poliovirus to form plaques indicative of reduced viral replication, further underscoring the importance of membrane remodeling by the amphipathic alpha-helix in possible relation to the formation of viral replication complexes.     

Effects of Parkinson’s disease on optic flow perception for heading direction during navigation

Visuoperceptual disorders have been identified in individuals with Parkinson’s disease (PD) and may affect the perception of optic flow for heading direction during navigation. Studies in healthy subjects have confirmed that heading direction can be determined by equalizing the optic flow speed (OS) between visual fields. The present study investigated the effects of PD on the use of optic flow for heading direction, walking parameters, and interlimb coordination during navigation, examining the contributions of OS and spatial frequency (dot density). Twelve individuals with PD without dementia, 18 age-matched normal control adults (NC), and 23 young control adults (YC) walked through a virtual hallway at about 0.8 m/s. The hallway was created by random dots on side walls. Three levels of OS (0.8, 1.2, and 1.8 m/s) and dot density (1, 2, and 3 dots/m²) were presented on one wall while on the other wall, OS and dot density were fixed at 0.8 m/s and 3 dots/m², respectively. Three-dimensional kinematic data were collected, and lateral drift, walking speed, stride frequency and length, and frequency, and phase relations between arms and legs were calculated. A significant linear effect was observed on lateral drift to the wall with lower OS for YC and NC, but not for PD. Compared to YC and NC, PD veered more to the left under OS and dot density conditions. The results suggest that healthy adults perceive optic flow for heading direction. Heading direction in PD may be more affected by the asymmetry of dopamine levels between the hemispheres and by motor lateralization as indexed by handedness.