Assessment of classification improvement in patients with Alzheimer's disease based on magnetoencephalogram blind source separation

OBJECTIVES: In this pilot study, we intended to assess whether a procedure based on blind source separation (BSS) and subsequent partial reconstruction of magnetoencephalogram (MEG) recordings might enhance the differences between MEGs from Alzheimer's disease (AD) patients and elderly control subjects. MATERIALS AND METHODS: We analysed MEG background activity recordings acquired with a 148-channel whole-head magnetometer from 21 AD patients and 21 control subjects. Artefact-free epochs of 20 s were blindly decomposed using the algorithm for multiple unknown signals extraction (AMUSE), which arranges the extracted components by decreasing linear predictability. Thus, the components of diverse epochs and subjects could be easily compared. Every component was characterised with its median frequency and spectral entropy (denoted by fmedian and SpecEn, respectively). The differences between subject groups in these variables were statistically evaluated to find out which components could improve the subject classification. Then, these significant components were used to partially reconstruct the MEG recordings. RESULTS: The statistical analysis showed that the AMUSE components which provided the largest differences between demented patients and control subjects were ordered together. Considering this analysis, we defined two subsets, denoted by BSS-{15,35} and BSS-{20,30}, which included 21 components (15-35) and 11 components (20-30), respectively. We partially reconstructed the MEGs with these subsets. Then, the classification performance was computed with a leave-one-out cross-validation procedure for the case where no BSS was applied and for the partial reconstructions BSS-{15,35} and BSS-{20,30}. The BSS and component selection procedure improved the classification accuracy from 69.05% to 83.33% using f(median) with BSS-{15,35} and from 61.91% to 73.81% using SpecEn with BSS-{20,30}. CONCLUSION: These preliminary results lead us to think that the proposed procedure based on BSS and selection of significant components may improve the classification of AD patients using straightforward features from MEG recordings.     

咪哒唑仑用于颌面外科清醒盲探插管的研究

目的 为咪哒唑仑用作清醒插管辅助用药提供临床资料。方法 选择４０例颌面外科手术病例,随机分为两组,每组２０例,采用盲探气管插管装置施行清醒插管。在清醒插管前５ｍｉｎ,Ｉ组给予芬太尼４μｇ／ｋｇ和咪哒唑仑０．０４ｍｇ／ｋｇ静注;Ⅱ组仅用芬太尼４μｇ／ｋｇ静注。观察比较两组在用药前（Ｔ１）、操作开始前即刻（Ｔ２）、食管气管引导管就位时（Ｔ３）、光索进入气管时（Ｔ４）和气管导管进入气管时（Ｔ５）的镇静评     

Tips and tricks to increase the success rate of blind tracheal intubation through the Air-Q™ versus the intubating laryngeal mask airway Fastrach™

BackgroundThe Air-Q intubating laryngeal airway is a new supraglottic airway device which overcomes some of the limitations inherent to the intubating laryngeal mask airway (ILMA Fastrach^™) for tracheal intubation. Previous studies showed lower success rate of the Air-Q^™ versus ILMA Fastrach^™. This study was conducted to illustrate new maneuvers for increasing the success rate of Air-Q^™ versus ILMA Fastrach^™ and compare between both devices.MethodsOne-hundred and seventy adult patients, ASA I or II, aged >16 years old undergoing elective surgery under general anesthesia were divided randomly into 2 equal groups (85 each). Group A: using Air-Q ILA size 3.5 or size 4.5 Group B: using ILMA size 4 or size 5 according to the manufacturer’s recommendations for body weight in both groups. The time and the total success rate of blind intubation through them in 2 attempts only were recorded. In Group A, extension of the head with cricoid pressure was applied. The hemodynamic response to devices insertion and the complications related to both devices were compared.ResultsIn Group A, the total success rate in 2 attempts was 94.12%, while in Group B, it was 96.47%. However, this difference was not statistically significant. The first attempt success rate was 81.18% in Group A, while it was 82.35% in Group B. The total time to intubate the hemodynamic response to device insertion and the incidence of complications (sore throat, trauma and hoarseness of voice) showed no statistically significant difference between both groups.ConclusionThis study showed that extension of the head with cricoid pressure greatly increases the success rate of blind intubation through the Air-Q to 94.12% versus the ILMA Fastrach 96.47% with no statistically significant difference between both devices.     

盲人青年学生的心理特点与施教原则

本文根据多年观察研究和对6所盲人培训机构共463名盲人青年学生的问卷调查,分析了盲人青年学生在认知、情感与情绪、意志、人际交往等方面的心理特点,并针对这些特点提出了“师生互信”、“针对性”、“正常化”、“环境适应”等施教原则。     

Diagnosis of nosocomial pneumonia in mechanically ventilated patients by the blind protected telescoping catheter

Objectives To demonstrate that blind insertion of the protected telescoping catheter (PTC-NB) through the orotracheal tube can provide reliable pulmonary samples for the diagnosis of nosocomial pneumonia (NP) in ventilated patients.Design We performed a random comparison between the protected telescoping catheter intoduced through a bronchofiberscope (PTC-B) and the PTC-NB to diagnose NP.Setting: A general intensive care unit of a University Hospital.Patients 40 consecutive patients on mechanical ventilation and with suspicion of NP. The diagnosis of NP was suspected by clinical and chest X-ray findings.Measurements and results NP was confirmed microbiologically in 26 (65%) patients and maintained in 8 patients by clinical and radiological criteria. PTC-NB confirmed the microbiological diagnosis of PN in 21 (80%) patients. The use of antibiotics prior taking respiratory samples reduced the sensitivity of PTC-NB and PTC-B from 100–74% and from 94–70% (p=0.001). Both techniques agreed in 24 of 33 (73%) patients but such agreement was better when PN was on the right lung. Two patients developed a self-limiting hemoptysis after the PTC-B procedure.Conclusions PTC-NB is as sensitive as specific as PTC-B for diagnosing PN in mechanically ventilated patients, being a much easier technique to use.     

两种方法检测LGC盲样及效果探讨

目的：检测LGC盲样中的小肠结肠炎耶尔森氏菌并对过程和结果进行探讨。方法①分离培养法。②实时荧光PCR法。结果两者均检出小肠结肠炎耶尔森氏菌。结论两种方法的有效结合对目标菌检出有更重要的意义。     

深圳市低视力和盲患者的生活质量分析

目的通过对深圳市低视力和盲人群进行问卷调查,了解低视力和盲患者的生活质量及影响生活质量的因素。为科学的制定低视力和盲康复方案提供一定的依据。方法对低视力和盲的患者进行低视力康复调查问卷一般检查评估表和生存质量的问卷调查,根据得分评估低力和盲对患者生存质量的影响。主要指标：低视力患者生活质量得分;盲患者生活质量得分。结果共联系了100名低视力和盲患者,完成问卷调查100份。其中低视力患者50例,盲50例。低视力患者生活质量得分为36．78±5．02。影响生活质量的因素主要有：经济状况、社交能力、活动能力。均P ＜0．01。盲患者生活质量得分为25．25±3．65;影响生活质量的因素主要有：经济状况、心理状况、自理能力。均P ＜0．01。结论低视力和盲患者都处于低质量生活水平,影响低视力和盲患者生活质量的相关因素大致相同,又不尽相同,要提高低视力和盲患者的生活质量水平,需要针对不同的主要影响因素。     

The Use of Key Informant Method for Identifying Children with Blindness and Severe Visual Impairment in Developing Countries

Purpose: An estimated 19 million children are visually impaired; of these, 1.4 million are irreversibly blind. A key challenge is to identify them early in life to benefit maximally from visual rehabilitation, and/or treatment. This aggregative review and structured literature analysis summarizes evidence of what it is about the key informant (KI) approach that works to identify children with blindness or severe visual impairment (B/SVI) in the community (for whom, to what extent, in what circumstances, in what respect, how and why).

Methods: Peer-reviewed (PubMed, hand search) and grey literature (Google, World Health Organization website, academic theses, direct requests) were included, and methods and criteria used for identification, productivity (number of children referred per KI), accuracy of referrals (positive predictive value, PPV), age of children with B/SVI, KI definition, sex, information about cost and comparisons aggregated.

Results: We included 31 documents describing 22 unique KI programs. Mostly KIs identified children with B/SVI in 1–3 weeks, i.e. “campaign mode.” In 60%, KIs were community volunteers, others formal health sector workers (FHSW). Around 0.02–1.56 children per KI (median = 0.25) were successfully recruited. PPV ranged from 12 to 66%. In two studies comparing FHSWs and community KIs, the latter were 8 and 10 times more productive.

Conclusion: KIs working in campaign mode may provide an effective approach to identifying children with B/SVI in communities. Including identification of ocular problems and/or other impairments has been recommended. Research on factors that influence effectiveness and on whether KIs continue to contribute could inform programs.     

Hand and joint paths during reaching movements with and without vision

 This study examines whether the kinematics of pointing movements are altered by the sensory systems used to select spatial targets and to guide movement. Hand and joint paths of visually guided reaching movements of human subjects were compared with two non-visual conditions where only proprioception was available: (1) movements of the same subjects with blindfolds, and (2) movements by congenitally blind subjects. While hand-path curvatures were overall quite small, sighted subjects wearing a blindfold showed a statistical increase in hand-path curvature compared with their visually guided movements. Blindfolded subjects also showed greater hand-path curvature than blind subjects. These increases in hand-path curvature for blindfolded subjects did not always lead to a decrease in joint-path curvature. While there were differences between blind subjects and sighted subjects using vision for some movement directions, there was no systematic difference between these two groups. The magnitude of joint-path curvature showed much greater variation than hand-path curvature across the movement directions. We found variation in joint-path curvature to be correlated to two factors, one spatial and one geometrical. For all subject groups, joint-path curvature tended to be smaller for sagittal-plane movements than for transverse or diagonal movements. As well, we found that the magnitude of joint-path curvature was also related to the relative motion at each joint. Joint-path curvature tended to increase when movements predominantly involved changes in shoulder angle and was minimal when movements predominantly involved elbow motion. The consistently small curvatures of hand trajectory across blind and sighted subjects emphasize the powerful tendency of the motor system to generate goal-directed reaching movements with relatively straight hand trajectories, even when deprived of visual feedback from very early in life. Received: 16 July 1997 / Accepted: 20 May 1998     

2011年微生物实验室质控盲样结果分析

目的通过质量控制考核评价实验室的检测能力,提高实验室的检测水平,保证检测结果准确、可靠。方法依据《中华人民共和国国家标准食品卫生微生物检验方法》及河南省和洛阳市下发的《卫生微生物质控作业指导书》对4份盲样菌株进行检验。结果从4份盲样菌株中检出1株志贺氏菌、2株金黄色葡萄球菌、1株阪崎肠杆菌,检测结果正确率为100%。结论实验室质控有助于提高检验水平。