Skin permeation and metabolism of di(2-ethylhexyl) phthalate (DEHP)

Phthalates are suspected to be endocrine disruptors. Di(2-ethylhexyl) phthalate (DEHP) is assumed to have low dermal absorption; however, previous in vitro skin permeation studies have shown large permeation differences. Our aims were to determine DEHP permeation parameters and assess extent of skin DEHP metabolism among workers highly exposed to these lipophilic, low volatile substances.     

Virtual planning in orthognathic surgery

Numerous publications regarding virtual surgical planning protocols have been published, most reporting only one or two case reports to emphasize the hands-on planning. None have systematically reviewed the data published from clinical trials. This systematic review analyzes the precision and accuracy of three-dimensional (3D) virtual surgical planning of orthognathic procedures compared with the actual surgical outcome following orthognathic surgery reported in clinical trials. A systematic search of the current literature was conducted to identify clinical trials with a sample size of more than five patients, comparing the virtual surgical plan with the actual surgical outcome. Search terms revealed a total of 428 titles, out of which only seven articles were included, with a combined sample size of 149 patients. Data were presented in three different ways: intra-class correlation coefficient, 3D surface area with a difference <2 mm, and linear and angular differences in three dimensions. Success criteria were set at 2 mm mean difference in six articles; 125 of the 133 patients included in these articles were regarded as having had a successful outcome. Due to differences in the presentation of data, meta-analysis was not possible. Virtual planning appears to be an accurate and reproducible method for orthognathic treatment planning. A more uniform presentation of the data is necessary to allow the performance of a meta-analysis. Currently, the software system most often used for 3D virtual planning in clinical trials is SimPlant (Materialise). More independent clinical trials are needed to further validate the precision of virtual planning.     

稳态视觉诱发脑机接口特征提取方法的研究

目的为有效提取稳态视觉诱发脑机接口(SSVEP-based brain-computer interface)中的脑电特征,提出一种基于独立成分分析(independent component analysis,ICA)与希尔伯特黄变换(HilbertHuang transform,HHT)的特征提取方法。方法对采集得到的脑电信号进行带通滤波,得到预处理的脑电信号,将滤波后的脑电信号作为ICA的输入,经过ICA实现独立成分的快速获取。引入HHT对独立成分进行经验模态分解(EMD),分解获取固有模态函数(intrinsic mode function,IMF),通过对IMF的频域分析,即可提取出特征。将ICA和HHT法同WT法、ICA法以及HHT法等常用的特征提取方法在频域、功率谱估计、在时间消耗等多方面进行比对分析。结果频域分析和功率谱估计中,本文提出的方法明显优于WT法和ICA法,略优于HHT法。时间消耗方面,本文提出的方法略优于HHT法。结论基于ICA和HHT的特征提取方法在稳态视觉诱发脑机接口的特征提取中是可行的,并有效去除了脑电信号中的噪声。     

‘The team for both sides?’ A qualitative study of change in heart failure services at three acute NHS Trusts

Heart failure (HF) is an increasingly prevalent long‐term condition that affects around 900,000 people in the United Kingdom (National Institute for Health and Clinical Excellence). The study examined how HF services in the English National Health Service (NHS) were changing, focusing particularly on the primary/secondary care interface. The maintenance of continuity in care in the face of increasing demand and financial pressures on health and social care was a key concern. Semi‐structured interviews were conducted with 22 members of staff working in HF services in three NHS acute Trusts in the West Midlands of England. Interviews were conducted between April and December 2011 with purposively selected participants and data were analysed using the Framework Method. Four main themes emerged from the analysis: service context, capacity, the primary/secondary interface and communication across boundaries. Barriers to, and facilitators of, continuity of care for patients with HF were identified within these themes. The findings provide insights into the structure, management and work of HF services in the acute and community settings. They highlight how local systems for the management of HF patients are developing in ways which are not necessarily consistent with national policy.     

弓形虫感染对小鼠和人子宫自然杀伤细胞的影响

目的　观察弓形虫感染对小鼠和人子宫自然杀伤细胞（uterine natural killer cells, uNK cells）比例、数量、分化和功能的影响,探讨uNK细胞在弓形虫感染致早孕流产中的作用。方法　妊娠第6.5天给予孕鼠腹腔注射弓形虫速殖子,建立孕早期弓形虫感染致流产小鼠模型,妊娠第9.5天分离小鼠子宫淋巴细胞。取人正常妊娠孕早期流产新鲜蜕膜组织,分离人子宫淋巴细胞,与弓形虫RH株速殖子体外共培养48 h（弓形虫与子宫淋巴细胞比例分别为0.5∶1、1∶1、2∶1）。采用流式细胞术检测小鼠uNK细胞表型（CD122、NK1.1、DX5）、人uNK细胞表型（CD3、CD56、CD11b、CD27）及胞内细胞因子γ⁃干扰素（interferon⁃γ, IFN⁃γ）和肿瘤坏死因子⁃α（tumor necrosis factor⁃α, TNF⁃α）表达水平。磁珠分选小鼠和人uNK细胞,以小鼠YAC⁃1或人K562细胞作为靶细胞、以小鼠或人uNK细胞作为效应细胞,采用乳酸脱氢酶（lactate dehydrogenase, LDH）释放法检测效应细胞/靶细胞比例分别为1∶1、5∶1、10∶1、20∶1时uNK细胞的杀伤功能。结果　妊娠第9.5天,弓形虫感染组小鼠流产率较对照组显著上升（83.02% vs. 3.51%;[χ2] = 71.359,P < 0.001）。与对照组比较,弓形虫感染组小鼠uNK细胞绝对数量显著降低[（4 547 ± 1 610）个/只 vs.（8 978 ± 3 339）个/只;U = 2.000,P < 0.05]、细胞表面NK1.1表达水平显著下降[（74.53 ± 8.37）% vs.（93.00 ± 1.11）%;U = 0.000,P < 0.05]、NK1.1⁃DX5⁃细胞比例显著上升[（20.10 ± 8.03）% vs.（5.04 ± 0.68）%;U = 0.000,P < 0.05]、NK1.1+DX5+细胞比例显著下降[（21.70 ± 12.48）% vs.（45.75 ± 2.26）%;U = 0.000,P < 0.05]、IFN⁃γ表达水平显著升高[（16.74 ± 1.36）% vs.（8.13 ± 1.90）%;U = 0.000,P < 0.05],但TNF⁃α表达水平无显著改变[（67.98 ± 9.20）% vs.（52.93 ± 10.42）%;U = 2.000,P > 0.05]。弓形虫感染组小鼠uNK细胞表现出较强杀伤能力,且杀伤作用随着效应细胞/靶细胞比例升高逐渐增强;效应细胞/靶细胞比例为1∶1、5∶1、10∶1、20∶1时,感染组uNK细胞对YAC⁃1细胞的杀伤活性分别为2.30%、4.32%、8.12%和12.65%,对照组分别为1.21%、1.63%、2.51%和3.22%。将人子宫淋巴细胞与弓形虫RH株速殖子共培养48 h后,弓形虫感染组人uNK细胞在子宫淋巴细胞中所占比例较对照组显著降低[弓形虫2∶1组 vs. 对照组：（6.61 ± 1.75）% vs.（17.48 ± 4.81）%;F = 7.307,P < 0.01]、绝对数量显著减少[弓形虫2∶1组vs. 对照组：（12 104 ± 5 726）个/孔 vs.（65 285 ± 21 810）个/孔;H =11.540,P < 0.01]。弓形虫感染组uNK细胞中,CD56brightCD16⁃调节型NK细胞亚群比例较对照组减少（弓形虫2∶1组vs. 对照组：（25.25 ± 5.90）% vs.（36.03 ± 4.51）%;F = 3.213,P > 0.05]、CD56dimCD16+杀伤型NK细胞亚群比例增加[弓形虫2∶1组vs. 对照组：（11.15 ± 2.15）% vs.（7.09 ± 2.24）%,F = 2.992,P > 0.05],两者比值显著降低[弓形虫2∶1组vs. 对照组：（2.37 ± 0.92）vs.（5.58 ± 2.39）;H = 8.228,P < 0.05];CD11b+CD27⁃细胞比例显著上升[弓形虫2∶1组vs. 对照组：（30.28 ± 6.91）% vs.（17.48 ± 4.67）%;H = 6.556,P < 0.05],IFN⁃γ [弓形虫2∶1组vs. 对照组：（14.13 ± 1.28）% vs.（15.19 ± 1.64）%;F = 1.639,P > 0.05]、TNF⁃α表达水平无显著改变[弓形虫2∶1组vs. 对照组：（54.76 ± 10.02）% vs.（50.33 ±3.67）%;F = 0.415,P > 0.05]。弓形虫感染组人uNK细胞具有较强杀伤能力,且杀伤作用随着效应细胞/靶细胞比例升高逐渐增强;效应细胞/靶细胞比例为1∶1、5∶1、10∶1、20∶1时,感染组uNK细胞对K562细胞的杀伤活性分别为11.90%、28.11%、49.91%和73.35%,对照组分别为11.21%、21.63%、33.51%和48.22%。结论　弓形虫感染对小鼠和人uNK细胞分化和分泌功能产生了不同影响,但均可引起小鼠和人uNK细胞绝对数量减少、杀伤功能增强。     

应用气-液界面染毒技术研究柴油机尾气对16HBE细胞的毒性作用

[目的]应用气-液界面染毒技术探索柴油机尾气对人支气管上皮(16HBE)细胞急性毒性作用. [方法]在流速为20 mL/min,37℃的条件下,用柴油机尾气分别对生长在多孔膜上的16HBE细胞持续染毒5、10、15、20、30 min,分别使用CCK-8(Cell Counting Kit-8)检测法、乳酸脱氢酶(LDH)释放法、中性红摄入法(NRU)检测柴油机尾气对细胞存活率的影响;对细胞存活率约50％以上的染毒组用流式细胞术检测柴油机尾气对细胞凋亡率的影响;同时对每个染毒组分别设置用滤膜过滤的洁净空气作为对照组,暴露时间和检测方法均与染毒组-致. [结果]3种存活率检测方法的结果表明,染毒组与对照组相比,柴油机尾气持续染毒15 min及更长时间以后,细胞存活率降低,差异有统计学意义(P＜ 0.05),且呈随染毒时间延长而逐渐降低的趋势.3种方法比较表明,低流速短时间柴油机尾气对16HBE细胞的损伤作用以细胞膜损伤最为显著,其次是线粒体损伤.用柴油机尾气持续染毒10、15 min,染毒组细胞早期凋亡率、晚期凋亡及坏死率较对照组均升高,差异均有统计学意义(P＜ 0.05).10、15 min染毒组的晚期凋亡及坏死细胞多于早期凋亡细胞(P＜0.05). [结论]气-液界面染毒技术可以应用于柴油机尾气等气溶胶有害物质的体外毒性研究;同时发现柴油机尾气导致的16HBE细胞急性毒性为细胞膜损伤、线粒体损伤及细胞凋亡.     

Closed-Loop Neurofeedback of α Synchrony during Goal-Directed Attention

α Oscillations in sensory cortex, under frontal control, desynchronize during attentive preparation. Here, in a selective attention study with simultaneous EEG in humans of either sex, we first demonstrate that diminished anticipatory α synchrony between the mid-frontal region of the dorsal attention network and ventral visual sensory cortex [frontal-sensory synchrony (FSS)] significantly correlates with greater task performance. Then, in a double-blind, randomized controlled study in healthy adults, we implement closed-loop neurofeedback (NF) of the anticipatory α FSS signal over 10 d of training. We refer to this closed-loop experimental approach of rapid NF integrated within a cognitive task as cognitive NF (cNF). We show that cNF results in significant trial-by-trial modulation of the anticipatory α FSS measure during training, concomitant plasticity of stimulus-evoked α/θ responses, as well as transfer of benefits to response time (RT) improvements on a standard test of sustained attention. In a third study, we implement cNF training in children with attention deficit hyperactivity disorder (ADHD), replicating trial-by-trial modulation of the anticipatory α FSS signal as well as significant improvement of sustained attention RTs. These first findings demonstrate the basic mechanisms and translational utility of rapid cognitive-task-integrated NF.SIGNIFICANCE STATEMENT When humans prepare to attend to incoming sensory information, neural oscillations in the α band (8–14 Hz) undergo desynchronization under the control of prefrontal cortex. Here, in an attention study with electroencephalography, we first show that frontal-sensory synchrony (FSS) of α oscillations during attentive preparation significantly correlates with task performance. Then, in a randomized controlled study in healthy adults, we show that neurofeedback (NF) training of this α FSS signal within the attention task is feasible. We show that this rapid cognitive NF (cNF) approach engenders plasticity of stimulus-evoked neural responses, and improves performance on a standard test of sustained attention. In a final study, we implement cNF in children with attention deficit hyperactivity disorder (ADHD), replicating the improvement of sustained attention found in adults.