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71.
Gaëlle Dzangué-Tchoupou Kuberaka Mariampillai Loïs Bolko Damien Amelin Wladimir Mauhin Aurélien Corneau Catherine Blanc Yves Allenbach Olivier Benveniste 《Autoimmunity reviews》2019,18(4):325-333
Background
Myositis is a heterogeneous group of muscular auto-immune diseases with clinical and pathological criteria that allow the classification of patients into different sub-groups. Inclusion body myositis is the most frequent myositis above fifty years of age. Diagnosing inclusion body myositis requires expertise and is challenging. Little is known concerning the pathogenic mechanisms of this disease in which conventional suppressive-immune therapies are inefficacious.Objectives
Our aim was to deepen our understanding of the immune mechanisms involved in inclusion body myositis and identify specific biomarkers.Methods
Using a panel of thirty-six markers and mass cytometry, we performed deep immune profiling of peripheral blood cells from inclusion body myositis patients and healthy donors, divided into two cohorts: test and validation cohorts. Potential biomarkers were compared to myositis controls (anti-Jo1-, anti-3-hydroxyl-3-methylglutaryl CoA reductase-, and anti-signal recognition particle-positive patients).Results
Unsupervised analyses revealed substantial changes only within CD8+ cells. We observed an increase in the frequency of CD8+ cells that expressed high levels of T-bet, and containing mainly both effector and terminally differentiated memory cells. The senescent marker CD57 was overexpressed in CD8+T-bet+ cells of inclusion body myositis patients. As expected, senescent CD8+T-bet+ CD57+ cells of both patients and healthy donors were CD28nullCD27nullCD127null. Surprisingly, non-senescent CD8+T-bet+ CD57- cells in inclusion body myositis patients expressed lower levels of CD28, CD27, and CD127, and expressed higher levels of CD38 and HLA-DR compared to healthy donors. Using classification and regression trees alongside receiver operating characteristics curves, we identified and validated a frequency of CD8+T-bet+ cells >51.5% as a diagnostic biomarker specific to inclusion body myositis, compared to myositis control patients, with a sensitivity of 94.4%, a specificity of 88.5%, and an area under the curve of 0.97.Conclusion
Using a panel of thirty-six markers by mass cytometry, we identify an activated cell population (CD8+T-bet+ CD57- CD28lowCD27lowCD127low CD38+ HLA-DR+) which could play a role in the physiopathology of inclusion body myositis, and identify CD8+T-bet+ cells as a predominant biomarker of this disease. 相似文献72.
目的探讨上海市宝山城区初、高中学生的心理特点及相关因素。方法以整群抽样的方法调查了上海市宝山区6所重点和非重点中学的学生共1289名,其中初中组544名,高中组745名,使用自编"中学生成长情况调查表"(共37题),均以"是"、"否"选择作答,由学生当场独立完成并立即收回。结果社会支持和家庭、学校、自身等方面都有较多的因素对中学生成长有重要影响,高中组和初中组部分项目存在显著性差异(P<0.05)。结论现代社会、家庭学校教育背景下中学生的健康成长与良好的社会支持、综合性教育、家长的正确参与密切相关,针对不同年龄阶段的学生应采取不同的教育、干预方式。 相似文献
73.
Electromyographic activity of m. rectus femoris at submaximal and maximal voluntary contractions was quantified by conventional integration technique and also be a more “qualitative” procedure of automated motor unit averaging and frequency spectrum analysis. By relating the EMG parameters to produced muscle tension it was observed that the integrated EMG increased in a slightly nonlinear fashion with the increase in muscle force. The other EMG variables also showed clear changes as a function of muscle tension. The averaged motor unit potential (AMUP) and its specific parameters (number of spikes, amplitude, rise time and amplitude-rise time ratio) showed such changes with muscle tension that they may be useful in estimation of the recruitment pattern of the different types of motor units. 相似文献
74.
Summary In single-fibre preparations the afferent discharges from prepolarized ampullae of Lorenzini responding to graded temperature steps were investigated in the dogfish (Scyliorhinus canicula).The transformation characteristics of the ampullary receptors, especially their differential thermosensitivity interfering with electrosensitivity, were analyzed. Prepolarization significantly influenced the dynamic component of differential thermosensitivity, while the static component remained practically unchanged. Hyperpolarization reduced positive and negative dynamic thermal responses: depolarization amplified them.Biological consequences of this bimodal interference for receptor transformation of superimposed thermal and electric stimuli and for decoding afferent ampullary impulse patterns are discussed.This investigation was supported by the Deutsche Forschungsgemeinschaft 相似文献
75.
神经症的研究进展 总被引:1,自引:1,他引:1
目的探讨神经症的病因,防御机制,应对方式,心理治疗及药物治疗的研究进展,以便为其研究、预防和治疗工作提供科学依据。方法以最近20年国内外有关神经症研究的成果为基础,采用文献研究法分析总结了近50余篇有关的研究论文的研究成果。结果神经症患者多内向,情绪明显不稳定,神经质影响心理症状最大;他们的父母较正常人的父母对子女缺乏情感温暖,并有过度的拒绝和过度保护,家庭不和睦,其在发病前一年内负性生活事件数目与严重程度均高于对照组(P<0.01);情绪表达受限,生活单调乏味,父母采取不良教养方式,人际关系紧张等。患者存在防御上的不适当,多使用不成熟或中间型防御机制,缺乏良好的应对方式。心理疗法主要有支持心理治疗,森田疗法,认知领悟疗法和精神分析疗法;而药物以三环类药物,苯二氮卓类为主。药物与心理疗法相结合的疗效比单纯应用心理治疗或药物治疗要好。结论神经症的病因主要有人格特征,家庭环境,生活事件,教养方式,人际关系等。采用心理干预与药物治疗相结合的方法是目前比较公认的。 相似文献
76.
颞叶癫痫的临床特点与脑电图分析 总被引:1,自引:0,他引:1
王建茹 《现代电生理学杂志》2003,10(2):65-66
目的:分析颞叶癫痫患的临床特点及脑电图定位的意义。方法:回顾分析92例颞叶癫痫患的脑电图。结果:左颞有癫痫样波42例,右颞有癫痫样波29例,双颞有癫痫样波21例,临床表现与癫痫样波发放部位有关,癫痫波的传导主要有容积传导和神经传导方式。结论:结合患临床表现与脑电图癫痫样波起始部位分析有助于致痫灶的定位。 相似文献
77.
The actual size and sites for puncture of the cisterna magna in adult Wistar rats were estimated on acrylic models. We proposed a new method for obtaining cerebrospinal fluid from narcotized rats. This method consists in controlled introduction of a needle into the cisterna magna through the skin and/or dura mater above this structure using a stereotactic micromanipulator. Experiments on rats with focal and global cerebral ischemia showed that this technique ensures single and repeated sampling of at least 50 microl liquor not containing blood admixtures. 相似文献
78.
BACKGROUND: Exposure to fungi is often assessed by culturing floor dust or air samples. Our objective was to evaluate the relationships between dustborne and airborne fungi and to identify factors that modify these relationships. METHODS: From November 1994 to September 1996 sequential duplicate 45-l air samples were collected in bedrooms of 496 homes in the Boston area, using a Burkard culture plate sampler. After air sampling, bedroom floors were sampled with a vacuum cleaner that was modified to collect dust in a cellulose extraction thimble. Dust was sieved, and the fine dust was dilution-plated onto DG-18 media. RESULTS: Concentrations of total culturable fungi per gram of bedroom-floor dust were correlated weakly, but significantly, with those of indoor air (r = 0.13, P < 0.05). Concentrations of some individual taxa in the dust and indoor air were also weakly associated. Adjusting for the concentrations of fungi in outdoor air, dustborne fungal concentrations were positively associated with those in indoor air for the taxa Cladosporium and Penicillium, but not for total fungi. The indoor air fungal levels were often predicted by different covariates to those predicting fungal levels in dust. The type of housing (house or apartment) and the presence of carpeting were often predictive factors for dust fungi. In contrast, outdoor fungal levels were often predictive of the indoor air fungal levels. CONCLUSIONS: Because our data do not indicate a strong overall relationship between culturable fungi in dust and indoor air, the results from these two methods (dust and air sampling) likely represent different types of potential fungal exposures to residents. It may be essential to collect both air and dust samples, as well as information on housing characteristics, as indicators for fungal exposure. 相似文献
79.
We used volumetric magnetic resonance imaging to examine sex differences in prefrontal tissue volumes of healthy aged and patients with Alzheimer’s disease (AD). Healthy subjects had greater total prefrontal volume than AD, and men had greater total prefrontal volume than women (ps ≤ 0.02). This was true for both gray and white matter volumes. There were no interactions between group and sex for total prefrontal volume. An exploratory analysis of each group suggested that sex differences in both gray and white matter in healthy aging are not sustained in AD. 相似文献
80.
J. Smolander V. Louhevaaral P. Oja 《International archives of occupational and environmental health》1984,54(4):295-302
Summary Ninety to ninety-five men (aged 27 to 46 years) from the police academy were the study subjects. Their prior habits of physical excercise, estimated aerobic capacity (
), muscular performance, and thickness of subcutaneous fat were determined. The policemen were taller (181 cm vs 175 cm) and heavier (84 kg vs 74 kg) than the average 20- to 40-year-old Finnish man, and their
(1 · min–1) was higher (3.41 1 · min–1 vs 2.96 1 min–1 The frequency of prior physical exercise significantly correlated with most of the variables studied. Those policemen who did not exercise at all (n = 12) were inferior to the average 20- to 40-year-old Finnish man on all the physical fitness tests, whereas the results of the most active policemen (n = 23) were clearly higher. The results indicate that the selection of heavier and taller men for police training guarantees a certain absolute level of physical performance capacity. However, the physical activity involved in police work is insufficient to maintain a high level of physical fitness, which must be achieved through participation in regular and effective physical training. 相似文献