Acute Effects of Individual Exposure to Fine Particulate Matter on Pulmonary Function in Schoolchildren

Objective This panel study aimed to determine the acute effects of exposure to fine particulate matter(PM_(2.5)) on schoolchildren's pulmonary function.Methods We selected 51 schoolchildren aged 9–12 years attending a full-time boarding school in Beijing, China, measured the indoor and outdoor PM_(2.5) concentrations for five consecutive days,calculated the PM_(2.5) time-weighted individual exposure levels based on the school micro-environmental concentrations and the time activity pattern recorded by schoolchildren, measured schoolchildren's pulmonary function on the fifth day. The survey was performed three times from December 2018 to April 2019. We used a linear mixed-effects model to evaluate the associations between PM_(2.5) and pulmonary function.Results During the three surveys, the median PM_(2.5) time-weighted individual exposure concentrations were 15.30 μg/m3, 48.92 μg/m3, and 42.89 μg/m3, respectively. There was a significant difference between the three surveys in vital capacity(VC), forced vital capacity(FVC), forced expiratory volume in one second(FEV_1) and forced expiratory volume in one second/forced vital capacity(FEV1/FVC)(P 0.05). The relevance analysis found that PM_(2.5) had lag effect on schoolchildren's pulmonary function,each 10 μg/m~3 increase in PM_(2.5) could cause largest decreases in FEF25%–75%, FEV_1/FVC, FEF75%, and FEV1 on lag 0–1 d(80.44 m L/s, 35.85%, 78.58 m L/s, and 61.34 m L, respectively), and largest decreases in FEF25% on lag 1 d(83.68 m L/s), in VC on lag 4 d(32.34 m L), and in FVC on lag 0–4 d(37.76 m L). Gender subgroup analysis revealed that the increase in PM_(2.5) caused a decrease in FEV_1/FVC and VC on the day of physical examination only in boys, and on lag days it caused changes in different pulmonary function indicators, both for boys and girls, but most of the pulmonary function indicators decreased more in boys than in girls.Conclusion Our findings show that acute PM_(2.5) exposure has significant effects on pulmonary function within 0–4 d, on both small airway indicators and large airway indicators. Boys' pulmonary function is more sensitive to PM_(2.5) than girls.     

Diagnosis and prognostic value of restrictive ventilatory disorders in the elderly: a systematic review of the literature

Although less extensively studied compared to pulmonary obstructive diseases, restrictive lung disease (RLD) is highly prevalent and frequently disabling in the adult and, more, the elderly population. The underlying conditions may be either primarily pulmonary diseases, such as idiopathic pulmonary fibrosis, or non respiratory conditions secondarily affecting the lung, e. g. congestive heart failure, or else conditions affecting the lung expansion, e. g. obesity or rib cage deformity. The diagnosis is frequently based on the measurement of surrogate indexes such as the forced vital capacity (FVC) used as a proxy for total lung capacity (TLC). As a consequence, diagnosis of RLD is often characterized by poor specificity. In the elderly, worsening in the quality of life and poor prognosis are variably, but significantly, associated to RLD, being the underlying condition an important source of variability. Several causes of RLD are preventable and treatable conditions. A prompt identification of these conditions may allow to slow the decline of respiratory reserve and, thus, to preserve both personal independence and resistance to acute respiratory infections. This review gives an update on the latest evidence available on the prevalence and the prognosis of RLD in the elderly. Studies were identified through systematic searches of the electronic database MEDLINE. Reference list of eligible papers were also manually searched.     

基于坐位平衡的虚拟康复训练系统软件设计

摘要：目的：为了克服脑卒中患者在坐位康复训练过程中因重复训练所产生的厌倦心理。本研究设计了一种用于坐位平衡功能训练的虚拟康复训练系统软件,旨在增加患者坐位康复训练的趣味性,激发患者主动训练的积极性,使康复训练可以取得更好的治疗效果;方法：本系统采用上下位机结构,上下位机之间通过蓝牙串口进行通信,软件基于Microsoft的Di-rectX接口进行设计,采用vc＋＋进行编程,使用纹理映射技术实现了地面场景的加载和渲染,并从．x文件中加载人物网格信息并对其渲染,根据下位机坐板上四个压力传感器的压力控制虚拟人的运动;结果：实现了患者通过调整身体重心来控制虚拟训练环境中虚拟人沿指定路径行走的功能。能同时给与病人视觉和听觉的双重刺激;结论：本系统软件可以提高病人坐位平衡康复训练的积极性,对需要进行长期康复训练的病人能起到更好的治疗效果。     

A ventromedial prefrontal dysrhythmia in obsessive-compulsive disorder is attenuated by nucleus accumbens deep brain stimulation

BackgroundObsessive-compulsive disorder (OCD) has consistently been linked to abnormal frontostriatal activity. The electrophysiological disruption in this circuit, however, remains to be characterized.Objective/hypothesisThe primary goal of this study was to investigate the neuronal synchronization in OCD patients. We predicted aberrant oscillatory activity in frontal regions compared to healthy control subjects, which would be alleviated by deep brain stimulation (DBS) of the nucleus accumbens (NAc).MethodsWe compared scalp EEG recordings from nine patients with OCD treated with NAc-DBS with recordings from healthy controls, matched for age and gender. Within the patient group, EEG activity was compared with DBS turned off vs. stimulation at typical clinical settings (3.5 V, frequency of stimulation 130 Hz, pulse width 60 μs). In addition, intracranial EEG was recorded directly from depth macroelectrodes in the NAc in four OCD patients.ResultsCross-frequency coupling between the phase of alpha/low beta oscillations and amplitude of high gamma was significantly increased over midline frontal and parietal electrodes in patients when stimulation was turned off, compared to controls. Critically, in patients, beta (16–25 Hz) -gamma (110–166 Hz) phase amplitude coupling source localized to the ventromedial prefrontal cortex, and was reduced when NAc-DBS was active. In contrast, intracranial EEG recordings showed no beta-gamma phase amplitude coupling. The contribution of non-sinusoidal beta waveforms to this coupling are reported.ConclusionWe reveal an increased beta-gamma phase amplitude coupling in fronto-central scalp sensors in patients suffering from OCD, compared to healthy controls, which may derive from ventromedial prefrontal regions implicated in OCD and is normalized by DBS of the nucleus accumbens. This aberrant cross-frequency coupling could represent a biomarker of OCD, as well as a target for novel therapeutic approaches.     

Autoschizis: a novel cell death

Vitamin C (VC) and vitamin K(3) (VK(3)) administered in a VC:VK(3) ratio of 100:1 exhibit synergistic antitumor activity and preferentially kill tumor cells by autoschizis, a novel type of necrosis characterized by exaggerated membrane damage and progressive loss of organelle-free cytoplasm through a series of self-excisions. During this process, the nucleus becomes smaller, cell size decreases one-half to one-third of its original size, and most organelles surround an intact nucleus in a narrow rim of cytoplasm. While the mitochondria are condensed, tumor cell death does not result from ATP depletion. However, vitamin treatment induces a G(1)/S block, diminishes DNA synthesis, increases H(2)O(2) production, and decreases cellular thiol levels. These effects can be prevented by the addition of catalase to scavenge the H(2)O(2). There is a concurrent 8- to 10-fold increase in intracellular Ca(2+) levels. Electrophoretic analysis of DNA reveals degradation due to the caspase-3-independent reactivation of deoxyribonuclease I and II (DNase I, DNase II). Redox cycling of the vitamins is believed to increase oxidative stress until it surpasses the reducing ability of cellular thiols and induces Ca(2+) release, which triggers activation of Ca(2+)-dependent DNase and leads to degradation of DNA. Recent experiments indicate that oral VC:VK(3) increases the life-span of tumor-bearing nude mice and significantly reduces the growth rate of solid tumors without any significant toxicity by reactivating DNase I and II and inducing autoschizis. This report discusses the mechanisms of action employed by these vitamins to induce tumor-specific death by autoschizis.     

米瓦罐的营养成分分析

米瓦罐(S．ilene conoideaL．)，又称麦瓶草、面条棵，属石竹科，蝇子草属。一年生草本，高25～60cm，全株密生腺毛。在我国主要分布于黄河流域和长江流域各省区，西至新疆和西藏。常生于麦田中或荒地草坡，为麦田普遍生长的一种杂草。近年来由于麦田除草剂的使用，野生米瓦罐在大田较难见到。米瓦罐幼苗可作为野菜，徐淮地区有食用野生米瓦罐幼嫩植株的习惯，多以蒸食为主，也可以炒食，凉拌、做汤。全草药用，     

Comparison of relative forced expiratory volume of one second with dynamic magnetic resonance imaging parameters in healthy subjects and patients with lung cancer

PURPOSE: To assess relative forced expiratory volume in one second (FEV1/vital capacity (VC)) in healthy subjects and patients with a lung tumor using dynamic magnetic resonance imaging (dMRI) parameters. MATERIALS AND METHODS: In 15 healthy volunteers and 31 patients with a non-small-cell lung carcinoma stage I (NSCLC I), diaphragmatic length change (LE1) and craniocaudal (CC) intrathoracic distance change within one second from maximal inspiration (DE1) were divided by total length change (LE(total), DE(total)) as a surrogate of spirometric FEV1/VC using a true fast imaging with steady-state precession (trueFISP) sequence (TE/TR = 1.7/37.3 msec, temporal resolution = 3 images/second). Influence of tumor localization was examined. RESULTS: In healthy volunteers FEV1/VC showed a highly significant correlation with LE1/LE(total) and DE1/DE(total) (r > 0.9, P < 0.01). In stage IB tumor patients, comparing tumor-bearing with the non-tumor-bearing hemithorax, there was a significant difference in tumors of the middle (LE1/LE(total) = 0.63 +/- 0.05 vs. 0.73 +/- 0.04, DE1/DE(total) = 0.66 +/- 0.05 vs. 0.72 +/- 0.04; P < 0.05) and lower (P < 0.05) lung region. Stage IA tumor patients showed no significant differences with regard to healthy subjects. CONCLUSION: dMRI is a simple noninvasive method to locally determine LE1/LE(total) and DE1/DE(total) as a surrogate of FEV1/VC in volunteers and patients. Tumors of the middle and lower lung regions have a significant influence on these MRI parameters.     

Modification of motor activity,passive avoidance conditioning and evoked potentials by microinjections of strychnine in both caudate nuclei in cats

Passive avoidance conditioning (PAC) seems to depend on inhibitory actions within the caudate nucleus (CN). Thus topical application of strychnine could block those influences. In cats, with permanently implanted cannulae in the head of the CN, bilateral microinjections of 100 μg of strychnine produced a stereotyped behavior of grooming and running with the extremities flexed to dark places. When placed into a two compartment chamber for a PAC acquisition they would not move from the dark compartment to the illuminated one. After decreasing the illumination some cats crossed and the acquisition test was performed. Twenty four hours later they showed the learned response. A second retention test was not modified by another strychnine application. These results contrast with those obtained by picrotoxin microinjections with disrupt the retention of a PAC. However, strychnine affect the evoked potentials (EP) recorded in CN by n. centralis medialis (NCM) stimulation by decreasing a positive peak, which probably represents post-synaptic inhibition and increasing the late positive component. In the lateral geniculate body strychnine affected a late positive wave and in the occipital cortex it increased the initial negative peaks and decreased the late positive ones of the potentials evoked by flash stimulation. These findings suggest a more subtle role of the CN in the regulation of visual information,which is probably related with the attention processes.     

VC＋＋与MATLAB混合编程技术在生物电阻抗断层图像重建中的应用

目的：为满足电阻抗断层成像（EIT）过程中数据实时处理要求,开发肺呼吸过程电阻抗图像重建应用软件并阐述实现方法。方法：将MATLAB C＋＋数学库及Mathtools绘图函数库嵌入VC＋＋高级编程语言,实现动态调用图像重建算法、二维绘图函数及矩阵计算函数等,使其满足实时电阻抗断层成像数据处理与图像重构要求。结果：软件成功实现了肺呼吸过程的电阻抗断层动态成像与数据处理。结论：为电阻抗图像重建过程的实时数据处理提供了新方法。