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81.
Persistent pain remains a major health issue: common treatments relying on either repeated local injections or systemic drug administration are prone to concomitant side-effects. It is thought that an alternative could be a multifunctional cargo system to deliver medicine to the target site and release it over a prolonged time window. We nano-engineered microcapsules equipped with adjustable cargo release properties and encapsulated the sodium-channel blocker QX-314 using the layer-by-layer (LbL) technology. First, we employed single-cell electrophysiology to establish in vitro that microcapsule application can dampen neuronal excitability in a controlled fashion. Secondly, we used two-photon excitation imaging to monitor and adjust long-lasting release of encapsulated cargo in target tissue in situ. Finally, we explored an established peripheral inflammation model in rodents to find that a single local injection of QX-314-containing microcapsules could provide robust pain relief lasting for over a week. This was accompanied by a recovery of the locomotive deficit and the amelioration of anxiety in animals with persistent inflammation. Post hoc immunohistology confirmed biodegradation of microcapsules over a period of several weeks. The overall remedial effect lasted 10–20 times longer than that of a single focal drug injection. It depended on the QX-314 encapsulation levels, involved TRPV1-channel-dependent cell permeability of QX-314, and showed no detectable side-effects. Our data suggest that nano-engineered encapsulation provides local drug delivery suitable for prolonged pain relief, which could be highly advantageous compared to existing treatments. 相似文献
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《Journal of clinical neuroscience》2014,21(8):1409-1412
To evaluate the feasibility and accuracy of using the Acute Physiology, Age and Chronic Health Evaluation II (APACHE II) scoring system for predicting the risk of nosocomial infection in the neurological intensive care unit (NICU), 216 patients transferred to NICU within 24 hours of admission were retrospectively evaluated. Based on admission APACHE II scores, they were classified into three groups, with higher APACHE II scores representing higher infectious risk. The device utilization ratios and device-associated infection ratios of NICU patients were analyzed and compared with published reports on patient outcome. Statistical analysis of nosocomial infection ratios showed obvious differences between the high-risk, middle-risk and low-risk groups (p < 0.05). The area under the receiver operating characteristic curve of the APACHE II model in predicting the risk of nosocomial infection was 0.81, which proved to be reliable and consistent with the expectation. In addition, we found statistical differences in the duration of hospital stay (patient-days) and device utilization (device-days) between different risk groups (p < 0.05). Thus the APACHE II scoring system was validated in predicting the risk of nosocomial infection, duration of patient-days and device-days, and providing accurate assessment of patients’ condition, so that appropriate prevention strategies can be implemented based on admission APACHE II scores. 相似文献
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目的:探讨注意缺陷多动障碍(ADHD)儿童体内IL-1β、IL-6、TNF-α含量变化及可能的发病机制;分析IL-1β、IL-6、TNF-α与ADHD症状特征及行为问题的关系。方法:对35例符合DSM-Ⅳ诊断标准的ADHD和25例正常儿童进行血清IL-1β、IL-6、TNF-α浓度测定,选用Achenbach儿童行为量表(CBCL)进行行为评定,比较两组IL-1β、IL-6、TNF-α浓度水平,并与DSM-Ⅳ诊断标准和CBCL得分进行相关分析。结果:ADHD儿童IL-1β较对照组增高,差异有统计学意义(χ2=4.239,P=0.041;Z=2.051,P=0.040);IL-6较对照组增高,但差异不具统计学意义(χ2=3.138,P=0.074;Z=1.892,P=0.058);TNF-α较对照组降低,差异有统计学意义(χ2=5.173,P=0.023;Z=2.792,P=0.005);TNF-α与注意缺陷因子、多动/冲动因子负相关(r=-0.377,P=0.003;r=-0.274,P=0.034);IL-1β与注意缺陷因子正相关(r=0.273,P=0.035);TNF-α与CBCL注意问题、违纪行为、攻击行为、外向性、行为问题总分负相关(r=-0.325,P=0.011;r=-0.396,P=0.002;r=-0.306,P=0.017;r=-0.324,P=0.011;r=-0.346,P=0.007)。结论:ADHD儿童存在高水平的IL-1β和低水平的TNF-α;IL-1β尤其是TNF-α与ADHD注意缺陷症状及某些行为问题间存在关联性。 相似文献
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《Radiography》2018,24(4):366-369
IntroductionTo analyse the objective structured examination (OSE) results of the first cohorts of radiographers (n = 13) who successfully completed an accredited postgraduate programme in clinical reporting of neurological magnetic resonance imaging (MRI) examinations of the head and cervical spine.MethodsForty MRI examinations were used in the OSE which included a range of abnormal cases (prevalence of abnormal examinations approximated 50%) and included: haemorrhage, infarction, demyelination disease, abscess, mass lesions (metastatic deposits, meningioma, glioma, astrocytoma); and disc disease, cord compression, stenosis, ligament rupture, syringomyelia appearances on patients referred from a range of referral sources. Normal variants and incidental findings were also included. True/false positive and negative fractions were used to mark the responses which were also scored for agreement with the previously agreed expected answers based on agreement between three consultant radiologists' reports.ResultsThe mean sensitivity, specificity and agreement rates for all head and cervical spine investigations (n = 520) combined were 98.86%, 98.08% and 88.37%, respectively. The highest scoring cases were cases which included astrocytoma, disc protrusion with cord compression and glioma. The most common errors were related to syringomyelia, ligament rupture and vertebral fracture.ConclusionsThese OSE results suggest that in an academic setting, and following an accredited postgraduate education programme, this group of radiographers has the ability to correctly identify normal MRI examinations of the head/cervical spine and are able to provide a report on the abnormal appearances to a high standard. Further work is required to confirm the clinical application of these findings. 相似文献
88.
目的 比较SHR、WKY、SD大鼠行为学特征,探寻研究SHR大鼠注意缺陷多动障碍(ADHD)理想的对照模型。方法 运用旷场实验统计大鼠运动距离、运动速度、穿格数及理毛次数来评价SHR、WKY、SD大鼠自主运动情况;运用水迷宫实验检测三组大鼠的学习记忆能力。结果 旷场实验结果显示,SHR大鼠在总运动量、平均运动速度及穿格次数上较WKY及SD大鼠均显著增加(P<0.01);与WKY大鼠相比,SD大鼠运动距离显著高于WKY组(P<0.01),其运动速度及穿格数略高于WKY组(P<0.05);水迷宫隐匿站台实验中,与SHR大鼠相比,SD大鼠潜伏期较长(P<0.05),在潜伏期运动距离上,SD大鼠在训练第1天、第3天及第4天运动距离较SHR大鼠延长(P<0.05或P<0.01);比较WKY组,SD大鼠潜伏期及潜伏期运动距离较WKY在各个训练时间均有不同程度的下降(P<0.05或P<0.01)。在空间探索阶段,SD大鼠穿台次数及目标象限运动时间、距离比率等均较SHR大鼠有所减少(P<0.05),而较WKY大鼠则有不同程度的升高(P<0.05或P<0.01)。结论 WKY大鼠与SHR大鼠行为学差异过大,两者的比较存在一定的不足,增设SD大鼠作为SHR大鼠的对照组能够提升SHR大鼠行为学特征的可比性,更为客观的反映SHR大鼠的行为学特征。 相似文献
89.
Claire O’Driscoll Caroline Heary Eilis Hennessy Lynn McKeague 《Journal of child psychology and psychiatry, and allied disciplines》2012,53(10):1054-1062
Background: Children and adolescents with mental health problems are widely reported to have problems with peer relationships; however, few studies have explored the way in which these children are regarded by their peers. For example, little is known about the nature of peer stigmatisation, and no published research has investigated implicit attitudes thus ensuring that stigma is not well understood. To address this issue, the current study explored patterns of explicit and implicit stigmatisation of peers with depression and attention deficit hyperactivity disorder (ADHD). Methods: The sample was 385 children (M = 10.21 years) and adolescents (M = 15.36 years). Participants completed a questionnaire assessing explicit stigma towards an age‐ and gender‐matched peer with ADHD or depression and another peer with ‘normal issues’ who were described in vignettes. They also completed a modified version of the Implicit Association Test (IAT) that explored implicit attitudes towards the target peers. Results: Questionnaire data indicated that the peer with ADHD was perceived more negatively than the peer with depression on all dimensions of stigma, except perceived dangerousness and fear. In contrast, the IAT findings suggest that some participants had more negative views of the peer with depression than the peer with ADHD. Specifically, the findings demonstrate that adolescent males demonstrated significantly stronger negative implicit evaluations of depression compared with younger males and adolescent females. Conclusions: Children and adolescents demonstrate stigmatising responses to peers with common mental health problems. The nature and extent of these responses depends on the type of problem and the type of measurement used. The findings highlight the importance of using both explicit and implicit measures of stigma. 相似文献
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