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21.
《药学学报(英文版)》2020,10(9):1634-1645
Systematic administration of anti-inflammatory cytokine interleukin 4 (IL-4) has been shown to improve recovery after cerebral ischemic stroke. However, whether IL-4 affects neuronal excitability and how IL-4 improves ischemic injury remain largely unknown. Here we report the neuroprotective role of endogenous IL-4 in focal cerebral ischemia–reperfusion (I/R) injury. In multi-electrode array (MEA) recordings, IL-4 reduces spontaneous firings and network activities of mouse primary cortical neurons. IL-4 mRNA and protein expressions are upregulated after I/R injury. Genetic deletion of Il-4 gene aggravates I/R injury in vivo and exacerbates oxygen-glucose deprivation (OGD) injury in cortical neurons. Conversely, supplemental IL-4 protects Il-4−/− cortical neurons against OGD injury. Mechanistically, cortical pyramidal and stellate neurons common for ischemic penumbra after I/R injury exhibit intrinsic hyperexcitability and enhanced excitatory synaptic transmissions in Il-4−/− mice. Furthermore, upregulation of Nav1.1 channel, and downregulations of KCa3.1 channel and α6 subunit of GABAA receptors are detected in the cortical tissues and primary cortical neurons from Il-4−/− mice. Taken together, our findings demonstrate that IL-4 deficiency results in neural hyperexcitability and aggravates I/R injury, thus activation of IL-4 signaling may protect the brain against the development of permanent damage and help recover from ischemic injury after stroke. 相似文献
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Activity of glutathione S-transferase (GST) in midgut of gypsy moth caterpillars exposed to 10 and 30 μg Cd/g dry food was examined. Based on the enzyme reaction through conjugation with glutathione, overall activity remained unaltered after acute and chronic treatment. No-observed-effect-concentration (10 μg Cd/g dry food) significantly increased activity only after 3-day recovery following cadmium administration. Almost all comparisons of the indices of phenotypic plasticity revealed statistically significant differences. Despite the facts that GST has important role in xenobiotic biotransformation, our results indicate that this enzyme in insect midgut does not represent the key factor in cadmium detoxification. 相似文献
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《Ultrasound in medicine & biology》2015,41(12):3172-3181
Fetal activity parameters such as movements, heart rate and the related parameters are essential indicators of fetal wellbeing, and no device provides simultaneous access to and sufficient estimation of all of these parameters to evaluate fetal health. This work was aimed at collecting these parameters to automatically separate healthy from compromised fetuses. To achieve this goal, we first developed a multi-sensor–multi-gate Doppler system. Then we recorded multidimensional Doppler signals and estimated the fetal activity parameters via dedicated signal processing techniques. Finally, we combined these parameters into four sets of parameters (or four hyper-parameters) to determine the set of parameters that is able to separate healthy from other fetuses. To validate our system, a data set consisting of two groups of fetal signals (normal and compromised) was established and provided by physicians. From the estimated parameters, an instantaneous Manning-like score, referred to as the ultrasonic score, was calculated and was used together with movements, heart rate and the associated parameters in a classification process employing the support vector machine method. We investigated the influence of the sets of parameters and evaluated the performance of the support vector machine using the computation of sensibility, specificity, percentage of support vectors and total classification error. The sensitivity of the four sets ranged from 79% to 100%. Specificity was 100% for all sets. The total classification error ranged from 0% to 20%. The percentage of support vectors ranged from 33% to 49%. Overall, the best results were obtained with the set of parameters consisting of fetal movement, short-term variability, long-term variability, deceleration and ultrasound score. The sensitivity, specificity, percentage of support vectors and total classification error of this set were respectively 100%, 100%, 35% and 0%. This indicated our ability to separate the data into two sets (normal fetuses and pathologic fetuses), and the results highlight the excellent match with the clinical classification performed by the physicians. This work indicates the feasibility of detecting compromised fetuses and also represents an interesting method of close fetal monitoring during the entire pregnancy. 相似文献
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脑部胶质瘤是临床中常见的一种原发性脑肿瘤,具有复发率高、死亡率高以及治愈率低的特点。常规临床诊断主要依靠计算机断层扫描(CT)和磁共振成像(MRI)检查技术进行鉴别。随着成像技术和机器学习方法的不断发展,多模态影像智能分析技术已经逐步成为研究热点,在脑胶质瘤的病灶分割测量、肿瘤分级、预后生存周期预测和基因型辨别等方面具有重要的应用前景。本文重点介绍基于机器学习和多模态影像在脑胶质瘤临床辅助诊断和预后评估中的应用进展。 相似文献
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《The Journal of foot and ankle surgery》2020,59(3):553-559
This case report describes posterior tibial tendon (PTT) tendinopathy, valgus deformity with tenosynovitis, and osteopenia at the medial malleolus as the primary symptoms of a young patient with celiac disease (CD) without gastrointestinal symptoms. CD is an autoimmune condition that is a chronic inflammatory disorder of the small intestine triggered by ingestion of gluten in individuals with a particular genetic background. Without typical gastrointestinal symptoms, CD patients are often misdiagnosed or undiagnosed. The patient was diagnosed with CD by duodenal biopsy. He underwent a surgical procedure, including medial displacement calcaneal osteotomy, tenosynovectomy of the PTT and flexor digitorum longus (FDL), FDL transfer to the navicular for a pes planovalgus deformity, and drilling of the medial malleolus for a stress reaction. The mechanism of the PTT tear and associated heel valgus deformity was assumed to be related to the fact that his heel alignment on the affected side changed gradually from normal to valgus and pes planus owing to CD and mechanical stress, because his normal-side heel alignment was neutral before surgery and at final follow-up. His operated ankle was pain-free, with full range of motion, 1.5 years after surgery. The patient was able to restart running and exercise gradually. Foot and ankle specialists should consider the possibility of CD in patients presenting with a PTT tear without injury or trauma and osteopenia with no obvious reason. 相似文献