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期刊论文 3

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2007 3

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Cooling strategies and transport theories for brain hypothermia resuscitation

LIU Jing

《能源前沿（英文）》 2007年 第1卷 第1期   页码 32-57 doi: 10.1007/s11708-007-0004-z

摘要： The brain is one of the most important organs in a biological body whose normal function depends heavily on an uninterrupted delivery of oxygen. Unlike skeletal muscles that can survive for hours without oxygen, neuron cells in the brain are easily subjected to an irreversible damage within minutes from the onset of oxygen deficiency. With the interruption of cardiopulmonary circulation in many cardiac surgical procedures or accidental events leading to cerebral circulation arrest, an imbalance between energy production and consumption will occur which causes a rapid depletion of oxygen due to the interrupted blood-flow to the brain. Meanwhile, the cooling function of the blood flow on the hot tissue will be stopped, while metabolic heat generation in the tissues still keeps running for awhile. Under such adverse situations, the potential for cerebral protection through hypothermia has been intensively investigated in clinics by lowering brain temperature to restrain the cerebral oxygen demands. The reason can be attributed to the decreased metabolic requirements of the cold brain tissues, which allows a longer duration for the brain to endure reduced oxygen delivery. It is now clear that hypothermia would serve as the principal way for neurologic protection in a wide variety of emergency medicines, especially in cerebral damage, anoxia, circulatory arrest, respiratory occlusion, etc. However, although brain cooling has been found uniquely significant in clinical practices, the serious lack of knowledge on the mechanisms involved prevents its further advancement in brain resuscitation. Compared with the expanded trials in clinics, only very limited efforts were made to probe the engineering issues involved, which turns out to be a major obstacle for the successful operation of brain hypothermia resuscitation. From the viewpoint of biothermal medical engineering, the major theories and strategies for administering brain cooling can generally be classified into three categories: heat transfer, oxygen transport and cooling strategy. Aiming to provide a complete overview of the brain hypothermia resuscitation, this article comprehensively summarizes the recent progresses made in theoretical, practical and experimental techniques in the area. Particularly, attention is paid to the mathematical models to quantify the heat and oxygen transport inside the cerebral tissues. Typical cooling strategies to effectively lower brain temperature and thus decrease oxygen consumption rate in the cerebral tissues are analyzed. Approaches to deliver oxygen directly to the target tissues are discussed. Meanwhile, some future efforts worth pursuing within the area of brain cooling are suggested.

关键词： mathematical     interruption     hypothermia     metabolic     generation    

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Kinetic analysis of anaerobic phosphorus release during biological phosphorus removal process

DOU Junfeng, LIU Xiang, LUO Guyuan

《环境科学与工程前沿（英文）》 2007年 第1卷 第2期   页码 233-239 doi: 10.1007/s11783-007-0040-2

摘要： Enhanced biological phosphorus removal (EBPR) is a commonly used and sustainable method for phosphorus removal from wastewater. Poly-β-hydroxybutyrate (PHB), polyphosphate, and glycogen are three kinds of intracellular storage polymers in phosphorus accumulation organisms. The variation of these polymers under different conditions has an apparent influence on anaerobic phosphorus release, which is very important for controlling the performance of EBPR. To obtain the mechanism and kinetic character of anaerobic phosphorus release, a series of batch experiments were performed using the excessively aerated sludge from the aerobic unit of the biological phosphorus removal system in this study. The results showed that the volatile suspended solid (VSS) had an increasing trend, while the mixed liquid suspended sludge (MLSS) and ashes were reduced during the anaerobic phosphorus release process. The interruption of anaerobic HAc-uptake and phosphorus-release occurs when the glycogen in the phosphorus-accumulating-organisms is exhausted. Under the condition of lower initial HAc-COD, HAc became the limiting factor after some time for anaerobic HAc uptake. Under the condition of higher initial HAc-COD, HAc uptake was stopped because of the depletion of glycogen in the microorganisms. The mean ratio of ΔρP/Δρ, Δρ/ΔρPHB, ΔρP/ΔCOD, and ΔρPHB/ΔCOD was 0.48, 0.50, 0.44, and 0.92, respectively, which was nearly the same as the theoretical value. The calibrated kinetic parameters of the HAc-uptake and phosphorus-release model were evaluated as follows: Q was 164 mg/(g °h), Q was 69.9 mg/(g °h), K was 0.005, and KCOD was 3 mg/L. An apparently linear correlation was observed between the ratio of ΔρP/ΔCOD and pH of the solution, and the equation between them was obtained in this study.

关键词： interruption     process     ΔρP/Δρ     Enhanced biological     Poly-β-hydroxybutyrate    

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Impact of siRNA targeting pirh2 on proliferation and cell cycle control of the lung adenocarcinoma cell line A549

SU Yuan, JIN Yang, ZHANG Xiaoju, ZHOU Qiong, BAI Ming, ZHU Liping

《医学前沿（英文）》 2007年 第1卷 第4期   页码 359-363 doi: 10.1007/s11684-007-0069-4

摘要： The aim of this study was to investigate the role of pirh2 (p53-induced RING-H2) protein in the proliferation, apoptosis and cell cycle control of the lung cancer cell line A549. Pirh2 expression was detected by immunofluorescence, Western blot analysis and real-time polymerase chain reaction (PCR). Cell proliferation was assessed by cell counting kit-8 (CCK-8). Cell cycle control and apoptosis were analyzed by flow cytometry. The results showed that pirh2 was expressed in the cytoplasm of A549 cells. The inhibition of pirh2 expression by siRNA (psiRNA-pirh2) resulted in reduced cell proliferation and increased apoptosis. In addition, the number of G/G phase cells was increased but G/M cells were not affected significantly. Taken together, the inhibition of pirh2 expression in the lung adenocarcinoma cell line A549 resulted in reduced tumor cell growth via the inhibition of cell proliferation, the activation of apoptosis and the interruption of cell cycle transition.

关键词： control     interruption     cytoplasm     number     growth    

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标题 作者 时间 类型 操作

Cooling strategies and transport theories for brain hypothermia resuscitation

LIU Jing

期刊论文

Kinetic analysis of anaerobic phosphorus release during biological phosphorus removal process

DOU Junfeng, LIU Xiang, LUO Guyuan

期刊论文

Impact of siRNA targeting pirh2 on proliferation and cell cycle control of the lung adenocarcinoma cell line A549

SU Yuan, JIN Yang, ZHANG Xiaoju, ZHOU Qiong, BAI Ming, ZHU Liping

期刊论文