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Interactions between remote ischemic conditioning and post-stroke sleep regulation

《医学前沿（英文）》 2021年第15卷第6期页码 867-876 doi: 10.1007/s11684-021-0887-9

摘要： Sleep disturbances are common in patients with stroke, and sleep quality has a critical role in the onset and outcome of stroke. Poor sleep exacerbates neurological injury, impedes nerve regeneration, and elicits serious complications. Thus, exploring a therapy suitable for patients with stroke and sleep disturbances is imperative. As a multi-targeted nonpharmacological intervention, remote ischemic conditioning can reduce the ischemic size of the brain, improve the functional outcome of stroke, and increase sleep duration. Preclinical/clinical evidence showed that this method can inhibit the inflammatory response, mediate the signal transductions of adenosine, activate the efferents of the vagal nerve, and reset the circadian clocks, all of which are involved in sleep regulation. In particular, cytokines tumor necrosis factor α (TNFα) and adenosine are sleep factors, and electrical vagal nerve stimulation can improve insomnia. On the basis of the common mechanisms of remote ischemic conditioning and sleep regulation, a causal relationship was proposed between remote ischemic conditioning and post-stroke sleep quality.

关键词： remote ischemic conditioning sleep regulation stroke

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心肌远程调节及其临床相关性：现在一起来！ Review

Kristin Luther,Yang Song,Yang Wang,Xiaoping Ren,W. Keith Jones

《工程（英文）》 2015年第1卷第4期页码 490-499 doi: 10.15302/J-ENG-2015117

摘要：

急性心肌梗死(AMI) 是世界上致死和致残的主要病因。及时再灌注法是AMI的标准疗法，能够缩小梗死面积，提高患者存活率和改善预后。然而，25 %的患者在患心肌梗死(Ml) 后会进一步发展成为心力衰竭(HF)，且其中50%的患者会在5年内死亡。由于梗死面积是预断病人病情( 包括HF的形成) 的主要指标，因此，改善心肌的治疗方法具有极大的应用前景。在过去30年中，研究者已发现多种能够刺激内源性心肌保护通道的刺激物，这些刺激物能在缺血预适应(IPC)和缺血后适应以及心肌缺血情况下启动保护机制。当在心肌缺血发生前、发生期间或发生后即刻使用刺激物，在远离心脏的血管床中发生的短暂、可逆性局部缺血就会即刻引发心肌保护机制——这种现象被分别称为远程缺血预适应，远程缺血期适应和远程缺血后适应。尽管目前的研究尚未完全阐明远程缺血预适应(RIPC) 的作用机制，但RIPC与IPC在机制上有很多共同之处。RIPC的发现使研究转向了远程非缺血刺激的应用，包括神经刺激( 脊髓刺激和迷走神经刺激) 以及电针(EA)。笔者与其他研究人员发现并阐述了非缺血现象的机制，并将其定义为远程创伤预适应(RPCT)。通过刺激皮肤感觉神经来启动RPCT，这与穴位处神经刺激和EA既有相似性又有一定差异性。笔者在此次研究中还发现，可通过采用腹中线电刺激(与EA疗法相似) 来模拟RPCT，而且作为预适应刺激和后适应刺激( 在应用再灌注法时)，这种激活心肌保护机制的模式是非常有效的。通过对这些心肌保护现象的研究，学术界对心肌保护机制形成了一种全面且综合的理解，而且在过去的5~10 年期间, 这种理解变得逐渐清晰，即无论是缺血性刺激诱导还是非缺血性刺激诱导，其机制均相似。通过对文献中多种数据的综合考虑，我们认为所有的这些心肌保护“适应”现象均表示心肌保护机制的启动是从心肌适应网(含有特定介质和心肌细胞生存感受器) 的不同切入点进行的，该切入点包括NF-κB、Stat3/5、蛋白激酶C、舒缓激肽和mitoK_ATP 通道。神经系统传导通路可能代表了一种激活心脏和其他器官适应的新机制。研究表明，由于IPC和RIPC存在一定风险并且无法应用于某些患者，所以它们很难被转化为临床应用。因此，近期又新兴了一种神经刺激和痛感刺激的应用，这是一种激活心肌适应的潜在的非缺血性无创方法。作为引起心脏保护作用众多方法之一的后适应重点强调了临床相关性，这种临床相关性有助于在现有成熟的药物与电子疗法中加速新的治疗方向的突破。

关键词：远程心肌保护心肌适应非缺血性适应末端疼痛性刺激神经和分子机制临床可行性电子疗法

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Adiponectin: mechanisms and new therapeutic approaches for restoring diabetic heart sensitivity to ischemicpost-conditioning

null

《医学前沿（英文）》 2013年第7卷第3期页码 301-305 doi: 10.1007/s11684-013-0283-1

摘要：

Systemic inflammatory response following myocardial ischemia-reperfusion injury (IRI) to a specific organ may cause injuries. Ischemic post-conditioning (IPostC) has emerged as a promising method for myocardial protection against IRI both in experimental and in clinical settings. Enhancement of endogenous nitric oxide (NO) is one of the major mechanisms by which IPostC confers cardioprotection. However, the sensitivity of the diabetic heart to IPostC is impaired and the underlying mechanism is unknown. Adiponectin (APN) is an adipocyte-derived plasma protein with anti-diabetic and anti-inflammatory properties. Plasma levels of APN are decreased in obese subjects and in patients with type 2 diabetes. APN supplementation has been shown to increase NO production and attenuate myocardial IRI in normal (non-diabetic) animals. However, the effect of APN on myocardial injury in diabetic subjects, especially its potential in restoring the sensitivity of the diabetic heart to IPostC has not been investigated. In the current paper, we discussed the possible reasons why the myocardium of diabetic subjects loses sensitivity to IPostC and also highlighted the potential effectiveness and mechanism of APN in restoring IPostC cardioprotection in diabetes. This review proposes to conduct studies that may facilitate the development of novel and optimal therapies to enhance cardioprotection in patients with severe diseases such as diabetes.

关键词： adiponectin ischemic post-conditioning ischemia reperfusion injury diabetes

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Genetics of ischemic and hemorrhagic stroke in Chinese population

Wei-Li ZHANG MD, PhD, Ru-Tai HUI MD, PhD,

《医学前沿（英文）》 2010年第4卷第1期页码 21-28 doi: 10.1007/s11684-010-0013-x

摘要： Stroke is a major cause of adult death and disability worldwide. Epidemiological and animal studies have provided strong evidence that the pathogenesis of stroke is multi-factorial and induced by a combination of environmental and genetic risk factors, but the identification of individual causative variants remains little known. Genetic influences are likely to be polygenic with small effect sizes, and stroke itself consists of a number of different subtypes which may each have different genetic profiles. In addition, various ethnic populations may have different stroke risk, such as Asian race. The reasons for high risk of stroke among the Chinese, especially hemorrhagic stroke, remain unknown. Most human studies have taken a candidate gene approach using case-control methodology. To be reliably detected, small relative risks require large sample sizes, probably 1000 patients or more. Genome-wide association (GWA) study is an unbiased and comprehensive approach to identify common risk alleles for complex diseases. Recently, a multistage GWA study has identified three loci on chromosomes 2q, 8q and 9p to be associated with intracranial aneurysm in European and Japanese populations. Another GWA finding is the identification of risk variants for cardioembolic stroke on chromosome 4q25 in European populations. In this review, we mainly focus on the results from case-control association studies on genetic factors that play a role in the risk of ischemic and hemorrhagic stroke in Chinese population. The combined effects of multiple susceptibility genes for stroke risk are also summarized.

关键词： genetics ischemic stroke hemorrhagic stroke association study

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Investigation on regeneration and energy storage characteristics of a solar liquid desiccant air-conditioning

SHI Mingheng, DU Bin, ZHAO Yun

《能源前沿（英文）》 2007年第1卷第1期页码 85-90 doi: 10.1007/s11708-007-0008-8

摘要： Solar liquid desiccant air-conditioner is a new air-conditioning system in which liquid desiccant can be regenerated by solar energy and energy can be stored in the form of chemical energy in the liquid desiccant. In this paper regeneration and energy storage characteristics were studied theoretically and experimentally. Two criterion equations for heat and mass transfer in the regeneration process were obtained. The main factors that influence the regeneration process were analyzed. A principal solar liquid desiccant air-conditioning system under energy storage operating mode is proposed.

关键词： desiccant air-conditioning regeneration process air-conditioning system energy regeneration

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Implantation of human umbilical cord mesenchymal stem cells for ischemic stroke: perspectives and challenges

null

《医学前沿（英文）》 2015年第9卷第1期页码 20-29 doi: 10.1007/s11684-014-0371-x

摘要：

Ischemic stroke is a focal cerebral insult that often leads to many adverse neurological complications severely affecting the quality of life. The prevalence of stroke is increasing throughout the world, while the efficacy of current pharmacological therapies remains unclear. As a neuroregenerative therapy, the implantation of human umbilical cord mesenchymal stem cells (hUC-MSCs) has shown great possibility to restore function after stroke. This review article provides an update role of hUC-MSCs implantation in the treatment of ischemic stroke. With the unique “immunosuppressive and immunoprivilege” property, hUC-MSCs are advised to be an important candidate for allogeneic cell treatment. Nevertheless, most of the treatments are still at primary stage and not clinically feasible at the current time. Several uncertain problems, such as culture conditions, allograft rejection, and potential tumorigenicity, are the choke points in this cellular therapy. More preclinical researches and clinical studies are needed before hUC-MSCs implantation can be used as a routinely applied clinical therapy.

关键词： cellular therapy transplantation human umbilical cord mesenchymal stem cells ischemic stroke

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Quantitative proteomics revealed extensive microenvironmental changes after stem cell transplantation in ischemic

《医学前沿（英文）》 2022年第16卷第3期页码 429-441 doi: 10.1007/s11684-021-0842-9

摘要： The local microenvironment is essential to stem cell-based therapy for ischemic stroke, and spatiotemporal changes of the microenvironment in the pathological process provide vital clues for understanding the therapeutic mechanisms. However, relevant studies on microenvironmental changes were mainly confined in the acute phase of stroke, and long-term changes remain unclear. This study aimed to investigate the microenvironmental changes in the subacute and chronic phases of ischemic stroke after stem cell transplantation. Herein, induced pluripotent stem cells (iPSCs) and neural stem cells (NSCs) were transplanted into the ischemic brain established by middle cerebral artery occlusion surgery. Positron emission tomography imaging and neurological tests were applied to evaluate the metabolic and neurofunctional alterations of rats transplanted with stem cells. Quantitative proteomics was employed to investigate the protein expression profiles in iPSCs-transplanted brain in the subacute and chronic phases of stroke. Compared with NSCs-transplanted rats, significantly increased glucose metabolism and neurofunctional scores were observed in iPSCs-transplanted rats. Subsequent proteomic data of iPSCs-transplanted rats identified a total of 39 differentially expressed proteins in the subacute and chronic phases, which are involved in various ischemic stroke-related biological processes, including neuronal survival, axonal remodeling, antioxidative stress, and mitochondrial function restoration. Taken together, our study indicated that iPSCs have a positive therapeutic effect in ischemic stroke and emphasized the wide-ranging microenvironmental changes in the subacute and chronic phases.

关键词： ischemic stroke microenvironment induced pluripotent stem cells (iPSCs) positron emission tomography (PET) quantitative proteomics

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New developments in mobile air conditioning systems in China

Jiangping CHEN, Yu ZHAO, Zhaogang QI

《能源前沿（英文）》 2011年第5卷第1期页码 53-58 doi: 10.1007/s11708-010-0137-3

摘要： Global warming poses serious global concerns, and the mobile air conditioning (MAC) industry must be promoted to reduce greenhouse gas emissions. In this paper, the development of the MAC system and components for new energy vehicles, low global warming potential (GWP) refrigerants, methods to control refrigerant leakage, and new energy-saving technologies in China are introduced.

关键词： global warming potential mobile air conditioning (MAC) energy saving new developments

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Experimental investigation on desiccant air-conditioning system in India

Vijay MITTAL, B. Kant KHAN,

《能源前沿（英文）》 2010年第4卷第2期页码 161-165 doi: 10.1007/s11708-009-0070-5

摘要： An experimental investigation in India was presented to evaluate the performance and energy saving capacity of a desiccant air-conditioning system composed of a silica gel bed, a split type air-conditioner (1.0 ton refrigeration) installed in a room with a volume of 86.4 m, air ducts and a blower. The experiment was made in such a way that the percentages of return air, outdoor air and indoor air mixed with the air leaving the desiccant and desiccant bed thickness could be adjusted. Tests were conducted on several days with relatively similar ambient conditions. Under the test conditions in this experiment, a 7cm bed thickness is recommended with a maximum adsorption rate of 403g/h. The optimum percentages of air ratios were as follows: 10% of outdoor air, 10% of return air (mixed together at the desiccant bed inlet) and 80% of indoor air mixed with the dry air leaving the desiccant. The corresponding electricity saving was about 19%. As expected, simple economic analysis indicates that the desiccant air-conditioning is not viable for smaller cooling capacities.

关键词： air ratios ambient conditions desiccant air-conditioning silica gel

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Research progress in liquid desiccant air-conditioning devices and systems

Xiaohua LIU, Yi JIANG, Shuanqiang LIU, Xiaoyang CHEN,

《能源前沿（英文）》 2010年第4卷第1期页码 55-65 doi: 10.1007/s11708-009-0082-1

摘要： The developments on liquid desiccant air-conditioning systems were illustrated and summarized in this paper. In order to obtain a better dehumidification (or humidification) performance, liquid desiccant should be cooled (or heated) rather than air. Two fundamental modules were proposed, including basic spray module with extra heat exchanger and total heat recovery device, which could be combined to set up various kinds of liquid desiccant air processors. The operating principle of heat pump-driven outdoor air processor as well as heat-driven outdoor air processor was analyzed. The COP of the heat pump (or power)-driven outdoor air processor could be as high as 5.0 both in summer and in winter operating conditions. The COP of the hot water-driven processor (65°C–80°C) was 1.19 and 0.93, respectively, using evaporative indoor exhaust air or cooling water to cool the dehumidification process. The liquid desiccant air processor-based temperature and humidity-independent control air-conditioning system could save 20%–30% operating energy compared with the conventional air-conditioning system.

关键词： liquid desiccant heat and mass transfer performance air-conditioning

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Engine-driven hybrid air-conditioning system

Chaokui QIN , Hongmei LU , Xiong LIU , Gerhard SCHMITZ ,

《能源前沿（英文）》 2009年第3卷第1期页码 109-116 doi: 10.1007/s11708-009-0003-3

摘要： A hybrid air-conditioning system that combines an engine-driven chiller with desiccant dehumidification was configured and experimentally tested to provide reliable data for energy consumption and operation cost. The engine performance and the desiccant wheel performance were measured and a numeric model previously set up for dehumidification capacity prediction was validated. For a reference building, the results based upon measured data show that under present electricity/gas price ratio, more than 40% of operation cost can be saved by the hybrid system.

关键词： engine-driven chiller desiccant wheel hybrid air-conditioning system energy consumption

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Predication of increased plasma homocysteine level on the prognosis of Chinese patients with first-onset ischemic

YAN Jiangtao, SHAO Jiaomei, WANG Daowen, YUE Zhengliang, HUI Rutai

《医学前沿（英文）》 2008年第2卷第4期页码 352-355 doi: 10.1007/s11684-008-0067-1

摘要： Epidemiological studies show that increased plasma total homocysteine (tHcy) level was an independent risk factor of cardiovascular diseases. This study was aimed to investigate the relationship between tHcy level and prognosis of first-onset stroke in Chinese people. One hundred ninety six patients with first-onset ischemic stroke and ninety-five patients with first-onset hemorrhagic stroke were enrolled in this study. The patients were divided into two groups in terms of tHcy level (< 18 ?mol/L and ≥ 18 ?mol/L). The plasma tHcy level was detected by a high performance liquid chromatography method with fluorescence detection. All the patients underwent a 5-year follow-up. Survival analysis shows that the probability of death or new vascular events in the ischemic stroke patients with high tHcy level (≥ 18 ?mol/L) was significantly higher than that in the counterparts with lower tHcy level (< 18 ?mol/L) (50.9% and 28.7%, respectively, = 0.004). The relative risk of death or new vascular events was 2.363 (95% CI, 1.209 to 4.617, = 0.012) in ischemic stroke patients with high tHcy levels(≥ 18 ?mol/L) compared to those with a lower tHcy level (< 18 ?mol/L). The increased tHcy level was significantly associated with the risk of death or new vascular events (, 2.492, 95% CI, 1.148 to 5.407, = 0.021) in patients with ischemic stroke in the exclusion of the influence of other risk factors such as gender, age, body mass index, plasma cholesterol level, the history of hypertension, diabetes or smoking. However, in the patients with hemorrhagic stroke, there was no significant difference in the probability of death or new vascular events between patients with a high tHcy level and those with a lower tHcy level (33.3% and 28.2%, respectively, = 0.546). Increased tHcy level was an independent risk factor for a worse outcome in patients with first-onset ischemic stroke, but not in hemorrhagic stroke patients.

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concept of capillary active, dynamic insulation integrated with heating, cooling and ventilation, air conditioning

Mark BOMBERG

《结构与土木工程前沿（英文）》 2010年第4卷第4期页码 431-437 doi: 10.1007/s11709-010-0071-9

摘要： When a historic fa?ade needs to be preserved or when the seismic considerations favor use of a concrete wall system and fire considerations limit exterior thermal insulation, one needs to use interior thermal insulation systems. Interior thermal insulation systems are less effective than the exterior systems and will not reduce the effect of thermal bridges. Yet they may be successfully used and, in many instances, are recommended as a complement to the exterior insulation. This paper presents one of these cases. It is focused on the most successful applications of capillary active, dynamic interior thermal insulation. This happens when such insulation is integrated with heating, cooling and ventilation, air conditioning (HVAC) system. Starting with a pioneering work of the Technical University in Dresden in development of capillary active interior insulations, we propose a next generation, namely, a bio-fiber thermal insulation. When completing the review, this paper proposes a concept of a joint research project to be undertaken by partners from the US (where improvement of indoor climate in exposed coastal areas is needed), China (indoor climate in non-air conditioned concrete buildings is an issue), and Germany (where the bio-fiber technology has been developed).

关键词： capillary active insulation integrated heating cooling and ventilation air conditioning (HVAC) and building enclosure dynamic insulation switchable thermal resistance variable U-value walls

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Experimental investigation on oil-gas separator of air-conditioning systems

Dianbo XIN,Shuliang HUANG,Song YIN,Yuping DENG,Wenqiang ZHANG

《能源前沿（英文）》 2019年第13卷第2期页码 411-416 doi: 10.1007/s11708-017-0447-9

摘要： The oil-return system plays an important role in the variable refrigerant flow (VRF) systems because it ensures the reliable operation of the VRF systems. The oil-gas separator is the most essential component of the oil-return system, and the separation efficiency of the separator directly influences the performance of the VRF systems. Therefore, in this paper, a test rig was built to measure the oil discharge ratio of the compressor and the separation efficiency of the oil-gas separator. A sound velocity transducer was used to measure the oil mass concentration instantaneously, because the sound velocity was changed with the mass ratio of oil to refrigerant. The separation efficiency of the separator could be obtained by comparing the mass fraction of oil to refrigerant before and after the separator was connected to the system.

关键词： variable refrigerant flow system oil-gas separator separation efficiency

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Design and realization of a remote monitoring and diagnosis and prediction system for large rotating

Shaohong WANG, Tao CHEN, Jianghong SUN

《机械工程前沿（英文）》 2010年第5卷第2期页码 165-170 doi: 10.1007/s11465-009-0090-1

摘要： Traditional on-site fault diagnosis means cannot meet the needs of large rotating machinery for its performance and complexity. Remote monitoring and diagnosis technology is a new fault diagnosis mode combining computer technology, communication technology, and fault diagnosis technology. The designed remote monitoring and diagnosis and prediction system for large rotating machinery integrates the distributed resources in different places and breaks through shortcomings as the offline and decentralized information. The system can make further implementation of equipment prediction technology research based on condition monitoring and fault diagnosis, provide on-site analysis results, and carry out online actual verification of the results. The system monitors real-time condition of the equipment and achieves early fault prediction with great significance to guarantee safe operation, saves maintenance costs, and improves utilization and management of the equipment.

关键词： large rotating machinery remote monitoring fault diagnosis prediction system