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Arguably, the two most important causes of pathological healing in the skin are diabetes and ageing. While these factors have historically been considered independent modifiers of the healing process, recent studies suggest that they may be mechanistically linked. The primary contributor to diabetic pathology is hyperglycaemia, which accelerates the production of advanced glycation end products, a characteristic of ageing tissue. Indeed, advanced age also leads to mild hyperglycaemia. Here, we discuss emerging literature that reveals a hitherto unappreciated link between cellular senescence, diabetes and wound repair. Senescent cells cause widespread destruction of normal tissue architecture in ageing and have been shown to be increased in chronic wounds. However, the role of senescence remains controversial, with several studies reporting beneficial effects for transiently induced senescence in wound healing. We recently highlighted a direct role for senescence in diabetic healing pathology, mediated by the senescence receptor, CXCR2. These findings suggest that targeting local tissue senescence may provide a therapeutic strategy applicable to a broad range of chronic wound types.  相似文献   
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针对现有基于心冲击描记图进行心率检测存在的抗干扰性不足问题,提出一种鲁棒的心率检测模型,首先对原始信号中受干扰的片段进行补偿重构,然后将J峰作为特征波形,通过基于J峰频段的滤波与差分增强处理放大特征,并设计改进的峰值提取算法定位心跳点,进而得到心率估计值。实验结果表明,所用模型对于不同情形下的心冲击描记图信号均表现出良好的适应性,逐拍检测平均覆盖率为98.3%,平均准确率为98.4%。心率输出结果与金标准一致性高,误差范围控制在[±]5%以内,且运算实时性好,可以为临床或家庭保健提供良好的心率检测方案。  相似文献   
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IntroductionThe use of motor imagery (MI) has been shown to offer significant improvements in movement performance in sports, and is now receiving a lot of attention as a relatively new therapeutic approach which can be applied in rehabilitation. However, the effects of MI on the quality of movement is still unclear. This study explored the immediate effect of MI on reaching tasks in healthy subjects.Methods17 healthy individuals (33 ± 8.2 years) participated in the study. Surface electromyography (sEMG) and inertial measurement units (IMU) were used to identify muscle activity and angular velocity in both upper limbs. Participants performed a reach task using their dominant and non-dominant arms at their most comfortable speed, they were then asked to imagine themselves performing the same reaching task, and finally they were asked to repeat the reaching task.ResultsSignificant decreases were seen in the muscle activity between pre and post MI for Biceps Brachii, Anterior Deltoid and Triceps Brachii. In addition, a significant increase was seen in extension angular velocity post MI.DiscussionThe results indicate that the use of MI just after physical practice appears to have an immediate effect on the muscle activity and kinematics during a reaching task, which may suggest an improved quality of movement.ConclusionThis proof of concept study shows the potential for MI to improve the quality of performing reaching task and offers a possible therapeutic option for Stroke survivors and other neuromuscular disorders.  相似文献   
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Objective To observe the differential expression of high mobility group box-1 protein (HMGB1) in renal tissues of heat stroke mice models, and to explore its role in the pathogenesis of heat stroke associated acute kidney injury(HS-associated AKI). Methods According to random number table, 20 healthy male C57BL/6J mice were randomly divided into 2 groups, including normal control (n=10) and heat stroke group (n=10). The mice in heat stroke group were given with a 2-hour-exposure in biological simulation chamber (temperature 41℃, humidity 70%). Heat stroke was defined as anal temperature lasting more than 40 degrees Celsius. A 18F-deoxyglucose nuclide labeled vivo imaging was conducted with micro- positron emission tomography(PET)/computer tomography (CT). Serum creatinine was examined with blood example. In order to evaluate the pathological changes, HE stain was conducted with kidney tissue, and mitochondrial morphological changes in kidney tissue were observed by transmission electron microscopy. The expressions of HMGB1 and apoptosis inducing factor mitochondria associated 2 (Aifm2) were examined by immunohistochemical method, and the levels of HMGB1 and RAGE were examined by Western blotting. The cell apoptosis of renal tissue was detected by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay (TUNEL). The metabolomics of kidney tissue in mice were detected by liquid chromatography-mass spectrometry (LC-MS), and the pathway enrichment analysis was carried out by KEEG database. Results (1) The body temperature of the mice in heat shock group was significantly higher than that in normal control group 45 min after model establishment (P<0.05). The level of serum creatinine in heat shock group was significantly higher than that in normal control group (P<0.05), and the levels of 18F-deoxyglucose increased in skeletal muscle and visceral tissue of the mice in heat-shock group. (2) HE staining showed hemorrhage in collecting duct and tubular endothelial cell swelling, and mitochondrial swelling and deformation were observed by transmission electron microscopy in kidney tissue of the heat shock group. (3)Immunohistochemical method showed that the levels of Aifm2 and HMGB1 in heat shock group were higher (P<0.05). (4) Western blotting showed that the levels of HMGB1 and RAGE in heat shock group were higher than those in normal control group (P<0.05). (5) TUNEL showed that the number of cells with positive stain in kidney tissue of the heat shock group was higher than that in normal control group (P<0.05). (6) Between normal control group and heat shock group, 136 differential metabolites were detected in kidney tissues. After analysis by KEGG database, pathway abnormalities such as unsaturated fatty acid metabolism disorder may be associated with HS-associated AKI, and many differential metabolites such as adrenic acid may be important regulatory points in the pathogenesis. Conclusion Acute kidney injury is a common complication of heat shock. It may be related to the dysfunction of renal mitochondria and activation of apoptotic pathway caused by systemic hypercatabolism, which may be related to the disorder of unsaturated fatty acid metabolism and activation of HMGB1. Some differential metabolites may be of high value in HS- associated AKI studies.  相似文献   
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