EPP:一个与表情特征加工相关的ERPs晚期正成分

目的 研究与表情特征加工相关的事件相关脑电位（event-related potentials，ERPs）成分。方法 被试者为12名（7男5女）右利手健康大学生。刺激包括3种卡通面孔（中性、微笑、愤怒）和3种非面孔。要求被试者进行面孔识别（face recognition，FR）和面孔表情分类（facial expression classification，FEC）2种作业。记录32导脑电。结果 1）与FR任务相比，FEC任务产生明显的P580成分；2）FEC的ERP与FR的ERP的差异波形，表现出一个非常明显的中央一顶区分布的正差异（450～850ms），命名为表性加工正成分（expression processing positivity，EPP）；3）EPP的峰值潜伏期表现出明显的表情特征主效应，以愤怒面孔EPP的潜伏期最短，微笑面孔EPP的潜伏期最长。结论 EPP可能反映了表情特征的晚期加工。     

Agreement between Emergency Physicians and Psychiatrists Regarding Admission Decisions

Objective: To determine the level of agreement between emergency physicians (EPs) and psychiatrists regarding the need for acute psychiatric hospitalization and treatment for patients presenting with alleged psychiatric complaints.
Methods: A prospective, cross-sectional assessment of concordance between EPs and psychiatrists in psychiatric admission decisions was performed at an urban county, teaching hospital ED. The participants had been brought to the ED for psychiatric evaluation. The patients were interviewed by an attending EP or a senior-level resident, and a tentative impression and disposition were determined pfior to an independent examination and final disposition by a psychiatrist. Strength of physician group agrement was determined using the k statistic.
Results: The patient mean age was 37.5 ± 15 years; 51% were men. The most common reasons for evaluation were disruptive behavior (28%), overdose (24%), and danger to self (23%). Of the 156 patients, 47 (28.7%) were sent home without treatment, 10 (6.3%) were determined to need only medical treatment, and 6 (3.7%) were released with outpatient psychiatric treatment. There were 84 (55.7%) patients admitted for psychiatric treatment. The EPs and psychiatrists had only moderate agreement regarding danger to self (k = 0.44), danger to others (k = 0.40). substance abuse as the primary problem (k = 0.50), and need for psychiatric hospitalization (k = 0.54).
Conclusion: Moderate agreement between EPs and psychiatrists in key impressions and admission decisions suggests that shared training in psychiatric decision making, especially during residency training, is desired in this setting.     

Methodological challenges to control for immortal time bias in addressing drug effects in type 2 diabetes

There are multiple biases in using observational studies to examine treatment effects such as those from prevalent drug users, immortal time and drug indications. We used renin angiotensin system (RAS) inhibitors and statins as reference drugs with proven efficacies in randomized clinical trials (RCTs) and examined their effectiveness in the prospective Hong Kong Diabetes Registry using adjustment methods proposed in the literature. Using time-dependent exposures to drug treatments yielded greatly inflated hazard ratios (HR) regarding the treatment effects of these drugs for cardiovascular disease (CVD) in type 2 diabetes. These errors were probably due to changing indications to use these drugs during follow up periods, especially at the time of drug commencement making time-dependent analysis extremely problematic. Using time-fixed analysis with exclusion of immortal time and adjustment for confounders at baseline and/or during follow-up periods, the HR of RAS inhibitors for CVD was comparable to that in RCT. The result supported the use of the Registry for performing pharmacoepidemiological analysis which revealed an attenuated low low-density lipoprotein cholesterol related cancer risk with RAS inhibitors. On the other hand, time-fixed analysis with including immortal time and adjustment for confounders at baseline and/or during follow-up periods, the HR of statins for CVD was similar to that in the RCT. Our results highlight the complexity and difficulty in removing these biases. We call for validations of the methods to cope with immortal time and drug use indications before applying them to particular research questions, so to avoid making erroneous conclusions.     

Resolvin D1 controls inflammation initiated by glutathione-lipid conjugates formed during oxidative stress

Background and purpose:

Inflammation is associated with oxidative stress and local generation of lipid peroxidation-derived aldehydes, such as 4-hydroxy-trans-2-nonenal (HNE). In most tissues, HNE is readily conjugated with glutathione and presently it is unknown whether glutathionyl-HNE (GS-HNE) plays a functional role in inflammation. Here, we sought to determine whether GS-HNE is a mediator of oxidative stress-initiated inflammation and if its actions can be regulated by the anti-inflammatory and pro-resolving lipid mediator, resolvin D1 (RvD1).

Experimental approach:

GS-HNE was administered intraperitoneally to mice and peritoneal lavages were assessed for leukocyte infiltration and lipid mediators were targeted by mediator-lipidomics. RvD1 was administered to mice treated with GS-HNE and leukocyte infiltration was assessed in the peritoneum. Superoxide production and CD11b modulation were measured in isolated human polymorphonuclear leukocytes incubated with GS-HNE.

Key results:

GS-HNE (1–10 µg) evoked infiltration of Gr-1⁺ leukocytes into the peritoneum to form an inflammatory exudate. With isolated human polymorphonuclear leukocytes, GS-HNE stimulated both superoxide generation and CD11b expression. Among the lipid mediators, both cyclooxygenase- and lipoxygenase-derived pro-inflammatory eicosanoids, including prostaglandin E₂, leukotriene B₄ and cysteinyl leukotrienes, were generated in exudates of mice injected intraperitoneally with GS-HNE. RvD1, given i.v. in doses as low as 0.01–10.0 ng, sharply reduced GS-HNE-stimulated leukocyte infiltration (∼30–70%).

Conclusions and implications:

Glutathione conjugates of HNE, derived during oxidative stress, are pro-inflammatory in vivo. RvD1 protects against this oxidative stress-initiated inflammation.This article is part of a themed issue on Mediators and Receptors in the Resolution of Inflammation. To view this issue visit http://www3.interscience.wiley.com/journal/121548564/issueyear?year=2009     

Frozen Red Blood Cells in Transfusion

Red blood cells (RBCs) can be cryopreserved with shelf life of 10 years. However, shelf life of deglycerolized RBCs in conventional open system is just 24 hours, resulting in sporadic use of Frozen RBC (FS-RBC). Recently Naval Blood Research Laboratory (NBRL) method using ACP 215 (ACP^™ 215 Haemonetics Cell Processing System) has been introduced, where shelf life of deglycerolized RBC is 14 days. FS-RBC unit is prepared from single blood donation, which needs to be glycerolized and deglycerolized. NBRL method using ACP 215 in FS-RBC is described. Deglycerolized unit weighed between 325–350 gm with haemoglobin of 15–18 gm/dl and freeze- thaw- wash RBC recovery of 87%. Transfusion of deglycerolized RBC offered advantages such as elimination of need of crossmatching in emergent situations and reduction of transfusion reactions. FS-RBC by NBRL method using ACP 215 has advantages such as long shelf life, meeting unexpected high blood demand in mass casualties situations or availability of rare blood group requirement of individual patient. FS-RBC can be a potential candidate for Indian Armed Forces Blood programme for uninterrupted blood supply during peace and war.Key Words: Frozen red blood cell, Cryopreservation, Blood transfusion, Armed forces blood programme     

Seroprevalence of Cytomegalovirus among Voluntary Blood Donors

Background

Primary cytomegalovirus (CMV) infection in immunocompetent host is self limiting infection, leading to latency of virus. However congenital CMV and CMV infections in immunocompromised patients are associated with high morbidity and mortality. Transfusion transmitted-cytomegalovirus (TT-CMV) infection in low birth weight neonate and immunocompromised transfusion recipients is being increasingly reported. Studies recommended transfusion of CMV free or CMV safe blood in prevention of TT-CMV. In this background, the study was undertaken to assess the CMV seroprevalence in blood donor.

Methods

A prospective study was conducted in which 431 voluntary blood donors were screened for CMV IgG and IgM by EIA (Enzyme Immuno Assay).

Result

A total of 379 (87.9 %) voluntary blood donors were seropositive for CMV IgG. There was no statistical difference of CMV seropositivity and age. Further, seven (1.6%) subjects were both CMV IgM and IgG seropositive.

Conclusion

High seroprevalence of CMV in our donor population is a threat to the blood safety. Strategies in reducing the risk of TT- CMV are discussed. Use of prestorage leucodepleted ‘CMV safe’ blood components along with judicious use of blood is recommended in prevention of TT-CMV in high risk recipients.Key Words: Cytomegalovirus, Transfusion transmitted infections, Blood donors, Leucodepletion     

Co-immunization with interlukin-18 enhances the protective efficacy of liposomes encapsulated recombinant Cu-Zn superoxide dismutase protein against Brucella abortus

Brucellosis is a worldwide zoonotic disease caused by Brucella abortus and a number of closely related species. Brucellosis has severe impact on the health and economic prosperity of the developing countries due to the persistent nature of infection and unavailability of effective control measures. The Cu-Zn superoxide dismuatse (SOD) protein of Brucella have been extensively studied as a major antigen involved in bacterial evading mechanism of host defence. Being a critical pro-inflammatory cytokine interleukin-18 (IL-18) plays key role in induction of immune mediated protection against intracellular pathogens. In the present study, we aimed to investigate the immunogenic potential of fusogenic liposomes (escheriosomes) encapsulated recombinant Cu-Zn SOD (rSOD) protein alone or in combination with recombinant IL-18 (rIL-18). Escheriosomes encapsulated rSOD mediated immune responses were further increased upon co-immunization with rIL-18. Furthermore, immunization with escheriosomes encapsulated rSOD alone or in combination with rIL-18, increased resistance in mice against challenge with B. abortus 544.