Monitoring Of Dynamic Changes Research Articles

A Moving Weighted Harmonic Analysis Method for Reconstructing High-Quality SPOT VEGETATION NDVI Time-Series Data

Global or regional environmental change is of wide concern. Extensive studies have indicated that long-term vegetation cover change is one of the most important factors reflecting environmental change, and normalized difference vegetation index (NDVI) time-series data sets have been widely used in vegetation dynamic change monitoring. However, the significant residual effects and noise levels impede the application of NDVI time-series data in environmental change research. This study develops a novel and robust filter method, i.e., the moving weighted harmonic analysis (MWHA) method, which incorporates a moving support domain to assign the weights for all the points, making the determination of the frequency number much easier. Additionally, a four-step process flow is designed to make the data approach the upper NDVI envelope, so that the actual change in the vegetation can be detected. A total of 487 test pixels selected from SPOT VEGETATION 10-day MVC NDVI time-series data from January 1999 to December 2001 were used to illustrate the effectiveness of the new method by comparing the MWHA results with the results of another four existing methods. Finally, the long-term SPOT VEGETATION 10-day maximum-value compositing (MVC) NDVI time series for China from April 1998 to May 2014 was reconstructed by the use of the proposed method, and a test region in China was utilized to validate the effectiveness of the proposed MWHA method. All the results indicate that the reconstructed high-quality NDVI time series fits the actual growth profile of the vegetation and is suitable for use in further remote sensing applications.

Measurement of Cellular Redox in Pollen with Redox-Sensitive GFP (roGFP) Using Live Cell Imaging

Redox homeostasis is a fundamental property of living cells and responds actively to both cellular metabolism and external stimulus. The development of redox-sensitive GFP (roGFP) enables dynamic monitoring of changes in cellular redox poise (Hanson et al., 2014). When excited alternatively at 405 nm and 488 nm, these probes exhibit significant opposing shifts at the emission spectra (505-530 nm), which enables ratiometric measurement of relative redox values. A more oxidized environment results in a higher 405/488 ratio. Previously, successful application of roGFPs in leaf epidermis or root cells has been reported. Here we provide a protocol describing the application of roGFP1 imaging in growing pollen tubes by confocal laser scanning microscopy.

Peptide-bridged dinuclear Ru(II) complex for mitochondrial targeted monitoring of dynamic changes to oxygen concentration and ROS generation in live mammalian cells.

A novel mitochondrial localizing ruthenium(II) peptide conjugate capable of monitoring dynamic changes in local O2 concentrations within living cells is presented. The complex is comprised of luminescent dinuclear ruthenium(II) polypyridyl complex bridged across a single mitochondrial penetrating peptide, FrFKFrFK-CONH2 (r = D-arginine). The membrane permeability and selective uptake of the peptide conjugate at the mitochondria of mammalian cells was demonstrated using confocal microscopy. Dye co-localization studies confirmed very precise localization and preconcentration of the probe at the mitochondria. This precision permitted collection of luminescent lifetime images of the probe, without the need for co-localizing dye and permitted semiquantitative determination of oxygen concentration at the mitochondria using calibration curves collected at 37 °C for the peptide conjugate in PBS buffer. Using Antimycin A the ability of the probe to respond dynamically to changing O2 concentrations within live HeLa cells was demonstrated. Furthermore, based on lifetime data it was evident that the probe also responds to elevated reactive oxygen species (ROS) levels within the mitochondria, where the greater quenching capacity of these species led to luminescent lifetimes of the probe at longer Antimycin A incubation times which lay outside of the O2 concentration range. Although both the dinuclear complex and a mononuclear analogue conjugated to an octaarginine peptide sequence exhibited some cytotoxicity over 24 h, cells were tolerant of the probes over periods of 4 to 6 h which facilitated imaging. These metal-peptide conjugated probes offer a valuable opportunity for following dynamic changes to mitochondrial function which should be of use across domains in which the metabolic activity of live cells are of interest from molecular biology and drug discovery.

Advances in research on wetlands of the Tibetan Plateau

About 80% of the global wetlands are being degraded or lost, and wetland ecosystem has become one of the most endangered ecosystems in the world. As a sensitive area to global change and protective barrier for the security of ecosystems in Asia, the Tibetan Plateau has a wetland area of about 13.19×104km2, which is an important part of the wetland ecosystem in China. With increasingly more remote sensing technology applied, Tibetan Plateau wetland research entered a new period of rapid development. This article summarizes remote sensing research literature of the Tibetan Plateau from 1992 to 2013, aiming to provide a reference for Tibetan Plateau wetland research in the future. The following aspects of research are reviewed: monitoring methods, research topics, and existing problems. The analysis shows that:(1) In the past 30 years, the research on Tibetan Plateau wetlands was focused on dynamic change monitoring of wetland area, landscape patterns, and ecological environment based on remote sensing technology. Attention was paid to building models to analyze the trend of change of the wetlands in three dimensions, taking an ecological system perspective.(2) Such research concludes that: 1) From 1990 to 2006, the wetland area generally decrease at an annual rate of 0.13%, and the landscape diversity decline at an annual rate of 0.17%. 2) In contrast, from 2003 to 2009, the depth of the lakes on the Tibetan Plateau had increased at an annual rate of 0.20 m; from 1970 to 2011, water storage of the lakes increased at an annual rate of 2.2 km3; from 1976 to 2009, lake area of the interior drainage area of the plateau increased at an annual rate of 0.83%. 3) From 1965 to 2002, change of the Tibetan Plateau wetlands was controlled by the climate. Wetland degradation and change around areas of human activity are a result of increased human activities. The existing problems of remote sensing research of the Tibetan Plateau wetlands are that: accuracy of digital analysis of remote sensing images and cloud removal need to be improved; a comprehensive perspective is needed for the research of the Tibetan Plateau wetland system. Based on the review, this article identifies the following key areas of future research:(1) Taking full advantage of remote sensing monitoring of wetlands characterized by multidate, multispectral, real- time, dynamic, and repeated coverage. Strengthening comprehensive research and remote sensing research of areas lacking conventional data;(2) Establishing a regional specific wetland remote sensing classification system that is technically operable, and conducting basic research on improving the Tibetan Plateau wetland remote sensing classification system and applications;(3) Focusing more on quantitative study on ecosystem functions of wetlands and decision support system for wetland ecosystem management;(4) Discussing responses and adaptation mechanisms of the Tibetan Plateau wetland ecosystem under the background of global change, especially the differences in responses and adaptation mechanisms under the impacts of different temporal and spatial scales. Coupling the models of hydrology, ecology, meteorology, soil, and environment to predict the trend of wetland degradation and revealing regional differences of response between different areas of the plateau in the face of global change;(5) Advancing remote sensing methods for Tibetan Plateau wetland research, strengthening the integration of RS, GIS, and GPS methods, and promoting the construction of a Tibetan Plateau wetland information platform.

Dual tracer evaluation of dynamic changes in intratumoral hypoxic and proliferative states after radiotherapy of human head and neck cancer xenografts using radiolabeled FMISO and FLT.

BackgroundRadiotherapy is an important treatment strategy for head and neck cancers. Tumor hypoxia and repopulation adversely affect the radiotherapy outcome. Accordingly, fractionated radiotherapy with dose escalation or altered fractionation schedule is used to prevent hypoxia and repopulation. 18F-fluoromisonidazole (FMISO) and 18F-fluorothymidine (FLT) are noninvasive markers for assessing tumor hypoxia and proliferation, respectively. Thus, we evaluated the dynamic changes in intratumoral hypoxic and proliferative states following radiotherapy using the dual tracers of 18F-FMISO and 3H-FLT, and further verified the results by immunohistochemical staining of pimonidazole (a hypoxia marker) and Ki-67 (a proliferation marker) in human head and neck cancer xenografts (FaDu).MethodsFaDu xenografts were established in nude mice and assigned to the non-radiation-treated control and two radiation-treated groups (10- and 20-Gy). Tumor volume was measured daily. Mice were sacrificed 6, 24, and 48 hrs and 7 days after radiotherapy. 18F-FMISO, and 3H-FLT and pimonidazole were injected intravenously 4 and 2 hrs before sacrifice, respectively. Intratumoral 18F-FMISO and 3H-FLT levels were assessed by autoradiography. Pimonidazole and Ki-67 immunohistochemistries were performed.ResultsIn radiation-treated mice, tumor growth was significantly suppressed compared with the control group, but the tumor volume in these mice gradually increased with time. Visual inspection showed that intratumoral 18F-FMISO and 3H-FLT distribution patterns were markedly different. Intratumoral 18F-FMISO level did not show significant changes after radiotherapy among the non-radiation-treated control and radiation-treated groups, whereas 3H-FLT level markedly decreased to 59 and 45% of the non-radiation-treated control at 6 hrs (p < 0.0001) and then gradually increased with time in the 10- and 20-Gy-radiation-treated groups. The pimonidazole-positive hypoxic areas were visually similar in both the non-radiation-treated control and radiation-treated groups. No significant differences were observed in the percentage of pimonidazole-positive cells and Ki-67 index.ConclusionIntratumoral 18F-FMISO level did not change until 7 days, whereas 3H-FLT level markedly decreased at 6 hrs and then gradually increased with time after a single dose of radiotherapy. The concomitant monitoring of dynamic changes in tumor hypoxia and proliferation may provide important information for a better understanding of tumor biology after radiotherapy and for radiotherapy planning, including dose escalation and altered fractionation schedules.

基于RS与GIS的农村居民点空间变化特征与景观格局影响研究

PDF HTML阅读 XML下载 导出引用 引用提醒 基于RS与GIS的农村居民点空间变化特征与景观格局影响研究 DOI: 10.5846/stxb201307291976 作者: 作者单位: 四川师范大学 西南土地资源评价与监测教育部重点实验室,四川师范大学 西南土地资源评价与监测教育部重点实验室,四川师范大学,四川师范大学 西南土地资源评价与监测教育部重点实验室 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目（41301196）；国家社会科学基金项目（11XJY019）；国家973项目（2009CB421105） A study of spatial evolution characteristics of rural settlements and influences of landscape patterns on their distribution using GIS and RS Author: Affiliation: Key Lab of Land Resources Evaluation and Monitoring in Southwest,Ministry of Education,Sichuan Normal University,Key Lab of Land Resources Evaluation and Monitoring in Southwest,Ministry of Education,Sichuan Normal University,,Key Lab of Land Resources Evaluation and Monitoring in Southwest,Ministry of Education,Sichuan Normal University Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:农村居民点作为乡村地域空间人口聚居形态，是乡村聚落景观重要组成部分，其空间布局、演变特征受自然、社会、经济多重因素的影响。利用都江堰市2005年和2010年两期遥感影像提取农村居民点、坡度、道路、河流等矢量数据，借助RS、GIS空间分析技术，定量研究都江堰市农村居民点的空间变化过程、格局和趋势，并选取景观格局指数对影响农村居民点布局特征的因素进行深入分析。结果表明：（1）2005年和2010年都江堰市农村居民点的空间分布总体上均表现出显著的聚集趋势，2010年农村居民点的聚集程度要比2005年高，但居民点集聚的空间态势没有发生明显变化，仍然集中在都江堰市的东南部；（2）坡度、道路和河流对都江堰市农村居民点的布局有显著影响，其中超过80%的居民点分布在0-10°坡度范围内，超过50%的居民点分布在道路500 m范围内，近60%居民点分布在河流1000 m范围内；（3）农村居民点空间布局除了受地形因素影响外，还与国家级风景名胜区、世界文化遗产区等保护政策，农村土地综合整治和灾后重建等规划因素密切相关。该研究以期为农村居民点动态变化监测、农村土地整理效果评价、新农村规划等理论和实践提供重要决策参考和技术支撑。 Abstract:Forms of human habitation within rural settlements are a major component of rural landscapes. The spatial patterns and evolutionary characteristics of rural settlements are influenced by multiple factors, including natural, social, and economic elements. It is, therefore, important not only to properly identify and assess the spatial distribution patterns and evolutionary modes of rural settlements, but also to uncover causative laws and influential factors behind their evolution. This can facilitate scientific rural planning and enhance optimal distribution of urban and rural land resources. Our study is based on a series of digitalized vector data, including the locations of rural settlements, land slopes, rivers, and road networks obtained from remote sensing (RS) images of the city of Dujiangyan in Sichuan Province for 2005 and 2010. We applied analytical techniques derived from Geographic Information Systems (GIS) and RS to quantitatively analyze the processes, patterns, and trends of spatial evolution in rural settlements. Specifically, we explored landscape pattern indexes to examine in depth the factors influencing the distribution characteristics of rural settlements in the study area. Our results showed that: 1) In general, while there was significant clustering in the spatial distribution of rural settlements in Dujiangyan during both 2005 and 2010, this settlement pattern was even more significant in 2010. Along with an increase in the spatial scale, the degree of the clustering tendency also increased, reaching a maximum value at a scale of 13 km. 2) The presence of land slopes, roads, and rivers significantly influenced the distribution of rural settlements in Dujiangyan as evidenced by the following findings. More than 80% of settlements were located in areas with slopes of less than 10 degrees; over 50% of settlements were located within 500 m from a road network; and almost 60% were distributed within 1000 m of a river. 3) In 2005 as well as 2010, there was no obvious change in the concentrated locations of clusters, which were consistently found in the southeastern region of Dujiangyan City. However, during both time periods, fewer settlements were found in the townships of Hongkou, Longchi, and Qingcheng Mountain. The reason for this imbalance in the spatial distribution of rural settlements was that besides the influence by natural factors such as the landscape, the distribution patterns of rural settlements in Dujiangyan were also closely associated with several planning elements. These included a policy of protecting national regions of scenic interest and a World Cultural Heritage site located in the city, the rural land comprehensive consolidation projects and post-earthquake reconstruction planning. 4) Based on the above findings on factors that influence the distribution of rural settlements, our research suggests that comprehensive consideration of topographical and geological conditions is required for optimal adjustment of rural settlement patterns. Scientific planning procedures can promote the relocation of rural residents from villages to townships and urban areas, and help to lessen disruption in environmentally protected regions. They can also reinforce the effective use of land resources and increase land supporting capabilities. We expect our research to provide a methodological reference for similar research conducted in the future. It can also provide a theoretical and practical reference for rural land-related decision-making and technical support, for example, dynamic monitoring of changes in rural settlements, assessments of rural land consolidation, and the "New Socialist Countryside" rural planning policy. 参考文献 相似文献 引证文献

Online Electrochemical Monitoring of Dynamic Change of Hippocampal Ascorbate: Toward a Platform for In Vivo Evaluation of Antioxidant Neuroprotective Efficiency against Cerebral Ischemia Injury

Effective monitoring of cerebral ascorbate following intravenous antioxidant treatment is of great importance in evaluating the antioxidant efficiency for neuroprotection because ascorbate is closely related to a series of ischemia-induced neuropathological processes. This study demonstrates the validity of an online electrochemical system (OECS) for ascorbate detection as a platform for in vivo evaluation of neuroprotective efficiency of antioxidants by studying the dynamic change of hippocampal ascorbate during the acute period of cerebral ischemia and its responses to intravenous administration of antioxidants including ascorbate and glutathione (GSH). The OECS consists of a selective electrochemical detector made of a thin-layer electrochemical flow cell integrated with in vivo microdialysis. With such a system, the basal level of hippocampal ascorbate is determined to be 5.18 ± 0.60 μM (n = 20). This level is increased by 10 min of two-vessel occlusion (2-VO) ischemia treatment and reaches 11.51 ± 3.43 μM (n = 5) at the time point of 60 min after the ischemia. The 2-VO ischemia-induced hippocampal ascorbate increase is obviously attenuated by immediate intravenous administration of ascorbate (2.94 g/kg) or glutathione (5.12 g/kg) within 10 min after ischemia and the ascorbate level remains to be 3.75 ± 1.66 μM (n = 4) and 5.30 ± 0.79 μM (n = 5), respectively, at the time point of 60 min after ischemia. To confirm if the attenuated hippocampal ascorbate increase is attributed to the antioxidant-induced oxidative stress alleviation, we further study the immunoreactivity of 8-hydroxy-2-deoxyguanosine (8-OHdG) in the ischemic hippocampus and find that the 8-OHdG immunoreactivity is decreased by the administration of ascorbate or GSH as compared to the ischemic brain without antioxidant treatment. These results substantially demonstrate that the OECS for ascorbate detection could be potentially used as a platform for evaluating the efficiency of antioxidant neuroprotection in cerebral ischemia treatment.

Remote sensing monitoring of dynamic changes of vegetation information in Tangshan City

This paper aims at analyzing greenbelt distribution and change in Tangshan City and providing scientific basis and technical support for urban planning.In this paper,the authors provided a method for the extraction of the vegetation information in Tangshan City based on TM and ETM+ data.Vegetation information graph was calculated firstly by normalized difference vegetation index(NDVI),then through setting up the actual NDVI threshold parameter and the near infrared band threshold parameter,the accurate vegetation pixels were obtained,and vegetation information diagrams for several areas in Tangshan City were compiled.Using 3 periods of vegetation information diagrams during 1999—2009,a synthetic dynamic change diagram was computed.The diagram shows that,in the past 10 years,the park greenbelt as the mainly covering area of the city vegetation in Tangshan City has been increased.The effect of the South Lake ecological construction is obvious,and the city limits of Tangshan City have experienced expansion toward the peripheral area.

Remote sensing monitoring of dynamic changes of surface environment in Shizuishan mining area

In this paper,aerial images of the 1970s,SPOT5 satellite images of 2003 and RapidEye images of 2009 were respectively selected to establish interpretation keys based on field survey data.Then three phase remote sensing images with different sensors were interpreted by ArcGIS,and land change maps from 1970s to 2003 and from 2003 to 2009 were obtained by overlapping interpretation results.The change and mutual transformation of lands were analyzed,and their change rules and causes were obtained.The analytical results are summarized as follows: Firstly,from 1970s to 2003,the main change of lands in the Shizuishan mining area was that the vegetation coverage area and the cultivated land were transformed to residential area and wasteland as a result of infrastructure construction and soil erosion.In addition,the areas of gangues,coal piles and water increased because of mining activities.Secondly,the area of vegetation coverage showed the fastest increasing rate from 2003 to 2009.On the contrary,the areas of surface features of the mine,such as gangues and coal piles,decreased sharply,which was closely related to integrated renovation of the mining geo-environment.

Abstract 3048: The genome-wide contribution of microRNAs to gene regulation in Ewing sarcoma.

Abstract The identification of microRNA (miR) targets within a given cellular context still poses a largely unsolved problem. MiR targets are predicted based on the presence of seed sequences in the 3'UTR of mRNAs. Target candidate lists are filtered assuming mRNA destabilization, and validated by artificially forcing ectopic expression of miR analogs, or by interfering with miR expression by antagomirs. However, the expression level and amplitude of physiological miR variations is much smaller than experimentally induced miR perturbations. Crosslinking and immuno precipitation (CLIP) followed by sequencing of bound RNA allows monitoring of dynamic changes in miR/mRNA occupancy of RISC. However, it is unclear if increased miR activity will lead to increased target read counts due to elevated RISC occupancy or to decreased read counts as a consequence of target destabilization. Ewing sarcoma (ES) expresses an oncogenic transcription factor, EWS/FLI1.To study the impact of miRs to the gene regulatory network downstream of EWS/FLI1, we used a combination of mRNA and miR expression profiling, ChIP-seq, PAR-CLIP of AGO2, AGO2 knockdown, and SILAC monitoring of proteome changes in an inducible EWS/FLI1 knockdown ES cell line. Our data suggest that EWS/FLI1 perturbs gene regulation primarily on the transcriptional level and miRs play only a modulatory role for gene expression. Furthermore EWS/FLI1 affects the expression of many miR biogenesis and miR activity as well as RISC associated proteins. Knockdown of EWS/FLI1 results in pronounced changes of miR specific PAR-CLIP spectra. Disabled RISC activity lead to only minor changes in genome-wide mRNA expression. Our results are consistent with a complex role of the miRNome in the fine tuning of gene regulatory networks in Ewing sarcoma. Supported by grants EU-FP7 259348 and Austrian Science Fund FWF 24708-B21. Citation Format: David Herrero-Martin, Maximilian Kauer, Kristina B. Emdal, Grzegorz Sienski, Argyrou Fourtouna, Robert Kralovics, Jesper V. Olsen, Heinrich Kovar. The genome-wide contribution of microRNAs to gene regulation in Ewing sarcoma. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 3048. doi:10.1158/1538-7445.AM2013-3048

Cerebral blood flow velocity in sleep

Sleep is the most conspicuous alteration of cerebral function during the circadian rhythm. It is composed of a cyclic sequence of stages defined on the basis of electrophysiological parameters. The underlying functional activity of the human brain is reflected by sleep correlated changes of cerebral blood flow (CBF), CBF velocity and cerebral metabolism (CM). Transcranial Doppler sonography (TCD) allows to analyze the rapid adaptation processes of cerebral hemodynamics due to TCD capabilities for high temporal resolution and continuous recording during sleep using modern ultrasonic probes with special fixation devices. After the onset of sleep there is a significant progressive reduction of CBF velocity from the waking state to slow wave sleep. The beginning of REM sleep is accompanied by a marked increase in CBF velocity. Furthermore, TCD enables the assessment of perfusion changes in pathological sleep conditions. In sleep apnea syndrome an apnea-associated increase in CBF velocity occurs, which is attributed to apnea-related hypercapnia, whereas a rapid normalization of flow velocity occurs at the end of each apneic episode. TCD is a useful method for long-term and on-line monitoring of dynamic changes in cerebral perfusion during normal sleep and in sleep disorders.

Research on Poyang Lake Wetland Information Extraction and Change Monitoring Based on Spatial Data Mining

Abstract Poyang Lake wetland is the largest “kidney of the mainland”. It plays an important role in many aspects such as water storage, flood control, climate mediation and biological diversity protection. This paper first reviews the development of wetland RS monitoring and probes RS classification methods based on Spatial Data Mining; secondly gives analysis on spectrum features of RS images of Poyang Lake wetland, and sets up the Decision Trees Model; and then classified RS image by Decision Trees Model in Expert Classifier module of Erdas Imagine 2010 software, and achieves a relatively high precision. Finally it gives dynamic change monitoring on Poyang Lake Wetland based on multi-temporal RS image and grasps the changed situation to provide scientific proof for government decision making.

Quantitative Evaluation of Retinal Response to Laser Photocoagulation Using Dual-Wavelength Fundus Autofluorescence Imaging in a Small Animal Model

To demonstrate the usefulness of dual-wavelength fundus autofluorescence (FAF) imaging for noninvasive, quantitative monitoring of dynamic changes associated with healing of retinal photocoagulation lesions in a small animal model. Brown Norway rats, exhibiting substantial age-dependent lipofuscin autofluorescence, were used to characterize the kinetics of FAF recovery after retinal photocoagulation. An argon laser with a beam diameter of 100 μm, exposure duration of 0.1 seconds, and a range of laser powers (8-22 mW) were used to create subthreshold, threshold, and suprathreshold lesions. A modified retinal angiograph was used to obtain dual-wavelength FAF images at 488 and 514 nm to quantify and monitor changes in retinal fluorescence up to 6 months. Compared to white light funduscopy, the FAF images exhibited heightened definition and clarity of lesion boundaries immediately after laser exposure. No significant reduction in FAF was measured at or below laser powers of 8 mW. Furthermore, a linear, dose-dependent decrease in FAF (R(2) = 0.9605) was observed immediately after laser exposures of 13 to 22 mW. Complete recovery of baseline FAF was observed for 13.5 and 16 mW exposures at 3 weeks and 4 months, respectively. However, retinal damage was still evident at 6 months after suprathreshold exposure induced using 22 mW laser power. The accumulation of lipofuscin in the aged Brown Norway rat makes it a suitable small animal model for the characterization of laser-induced injury in the retina based on FAF. Dual-wavelength FAF measurements provide a sensitive, quantitative, noninvasive means of monitoring recovery of laser-induced retinal injury.

Dual energy CT monitoring of the renal corticomedullary sodium gradient in swine

To evaluate the feasibility of dual-energy CT (DECT) for monitoring dynamic changes in the renal corticomedullary sodium gradient in swine. This study was approved by our Institutional Animal Care and Use Committee. Four water-restricted pigs were CT-scanned at 80 and 140 kVp at baseline and at 5 min intervals for 30 min during saline or furosemide diuresis. The renal cortical and medullary CT numbers were recorded. A DECT basis material decomposition method was used to quantify renal cortical and medullary sodium concentrations and medulla-to-cortex sodium ratios at each time point based on the measured CT numbers. The sodium concentrations and medulla-to-cortex sodium ratios were compared between baseline and at 30 min diuresis using paired Student t-tests. The medulla-to-cortex sodium ratios were considered to reflect the corticomedullary sodium gradient. At baseline prior to saline diuresis, the mean medullary and cortical sodium concentrations were 103.8±8.7 and 65.3±1.7 mmol/l, respectively, corresponding to a medulla-to-cortex sodium ratio of 1.59. At 30 min of saline diuresis, the medullary and cortical sodium concentrations decreased to 72.3±1.0 and 56.0±1.4 mmol/l, respectively, corresponding to a significantly reduced medulla-to-cortex sodium ratio of 1.29 (P<0.05). At baseline prior to furosemide diuresis, the mean medullary and cortical sodium concentrations were 110.5±3.6 and 66.7±4.1 mmol/l, respectively, corresponding to a medulla-to-cortex sodium ratio of 1.66. At 30 min of furosemide diuresis, the medullary and cortical sodium concentrations decreased to 68.5±0.3 and 58.9±4.0 mmol/l, respectively, corresponding to a significantly reduced medulla-to-cortex sodium ratio of 1.16 (P<0.05). One of the 4 pigs developed acute tubular necrosis likely related to prolonged hypoxia during intubation prior to the furosemide diuresis experiment. The medulla-to-cortex sodium ratio for this pig, which was excluded from the mean medulla-to-cortex ratio above, was 1.07 at baseline and 1.15 at 30 min following the administration of furosemide. DECT monitoring of dynamic changes in the renal corticomedullary sodium gradient after physiologic challenges is feasible in swine.

Dynamic monitoring of changes of thrombomodulin and von Willebrand factor in patients with severe brain injury

Objective To investigate the changes of thrombomodulin （TM） and von Willebrand factor （vWf） and their clinical significance in patients with severe brain injury. Methods The study involved 62 patients with severe brain injury who were divided into diffuse axonal injury group （28 patients） and focal brain injury group （34 patients）. Then, the 62 patients were divided into young group （16-30 years old, 20 patients）, middle-aged group （31-65 years old, 20 patients） and elderly group （ 〉65 years old, 22 patients）. The serum levels of TM and vWf were determined at days 1 and 7 after injury respectively. ELISA method was employed to determine the serum levels of TM and vWf.Results The vWf in focal brain injury group was significantly higher than that of diffuse axonal injury group at days 1-7 after injury （ P 〈 0.05 ）. Compared with the young and middle-aged groups, the TM and vWf levels in the elderly group at day 1 after injury were significantly elevated （ P 〈 0. 05 ）. The TM levels in patients with delayed traumatic intracerebral hematoma （DTICH） were significantly higher than that in patients without DTICH （P 〈 0. 05）. Conclusions In the acute stage of severe brain injury,injury severity and activation of endothelial cells varies in patients with different types of injury and at different ages. TM is one of sensitive indicators to reflect the cerebal vascular endothelial cell injury. It is very meaningful to assess the prognosis of severe brain injury by measuring serum levels of TM and vWf and take TM as a predictive indicator for DTICH. Key words: Brain injuries; Thrombomodulin; von Willebrand factor

Transfusion medicine and proteomics. Alliance or coexistence?

Transfusion of blood components is one of the most frequently performed clinical operations1,2. Beginning with the discovery of the AB0-blood group system by Karl Landsteiner3, the clinical relevance of transfusing blood, blood derived cells or proteins has increased constantly. Today transfusion medicine is a medical discipline and blood transfusion is embedded into one of the most advanced and regularized quality management systems in clinical medicine. In this system collection, production, storage, and administration of blood products are events separated in time and location, thus facilitating the existence of networks of donation sites and blood banks and the treatment of patients with human blood derived therapeutics even in far off areas. Today blood processing allows the provision of separate blood constituents such as cellular blood products e.g. red blood cell concentrates, platelet concentrates and stem cells, as well as plasma derived therapeutics such as fresh frozen plasma, coagulation factor concentrates, or immunoglobulins. Such blood products are either obtained by fractionation following donation of whole blood or they are selectively obtained from the blood donor using cell separators and apheresis procedures to obtain either cellular subfractions of the blood or plasma. These advances in the production of blood components enable storage of blood products under different conditions e.g. platelets at 20 °C and red blood cells at 4 °C. Blood fractionation also facilitates the targeted selection of specific blood components in order to provide patients with distinct blood functions. Thus, the different blood components are administered according to special indications such as the need for oxygen carriers or the maintenance of blood coagulation. Moreover, transfusion medicine achieved a remarkable reduction in the risk of pathogen transmission with blood products such as human immunodeficiency virus (HIV), hepatitis C, and hepatitis B4. While transmission of these pathogens has become a rare event in the Western world, bacterial contamination of blood products is still an issue, especially for platelet concentrates5. Despite the achievements just mentioned, transfusion medicine still faces a number of challenges with potential great impact on medical care systems. First the blood supply to demand ratio will change tremendously in the Western world due to the demographic changes with a growing older population and a declining birth rate2. This will require further reduction of waste of blood products e.g. by improvement of storage conditions and prolongation of storage time. Second, new emerging pathogens, which may not necessarily be known today or considered as a relevant transfusion transmissible agent, could easily thwart the blood supply. Prions causing variant Creutzfeld-Jacob-Disease (vCJD) are one recent example illustrating the need for ongoing activities to prevent pathogen transmission via blood products6. All approaches to reduce pathogen transmission or to extend storage of blood components have to maintain the integrity and function of blood cells and plasma proteins. In view of the complex composition of blood products and the constantly increasing regulatory requirements in transfusion medicine, monitoring of the effects of different maneuvers and interventions on the integrity of a blood product is becoming an issue of increasing importance. This will likely also require the application of more sensitive technologies. Technology advancements in the field of proteomics but particularly mass spectrometry have provided an entirely new view on the protein inventory of cells and cellular compartments by allowing fast and highly sensitive identification and analysis of thousands of proteins, both qualitatively and quantitatively. Such a comprehensive monitoring of dynamic changes of the protein levels but also of post-translational modifications7 is particularly useful for blood plasma and cells without a nucleus such as red blood cells and platelets. Although de novo protein synthesis has been convincingly demonstrated in platelets8 it occurs to a limited extend and is confined to pre-existing RNA. Application of proteomic technologies to different blood cells and plasma proteins has been subject of some excellent review articles9–12. Most of these studies have been performed for research questions not directly related to transfusion medicine. Only within the last five years, researchers in transfusion medicine have started to adopt proteomics to a larger extent to analyze blood products for patient care13. This review does focus on the potential of proteomics to address some of the current issues in transfusion medicine and provides a current status of proteomics in transfusion medicine.

The Monitoring of Dynamic Changes of Soil Salinization in the Downstream Oasis of the Kaidu River Based on Remote Sensing Technology

The Monitoring of Dynamic Changes of Soil Salinization in the Downstream Oasis of the Kaidu River Based on Remote Sensing Technology

Dynamic monitoring of changes in endothelial cell-substrate adhesiveness during leukocyte adhesion by microelectrical impedance assay

Adhesion of leukocytes to endothelial cells in inflammation processes leads to changes of endothelial cell-substrate adhesiveness, and understanding of such changes will provide us with important information of inflammation processes. In this study, we used a noninvasive biosensor system referred to as real-time cell electronic sensor (RT-CES) system to monitor the changes in endothelial cell-substrate adhesiveness induced by human monoblastic cell line U937 cell adhesion in a dynamic and quantitative manner. This assay, which is based on cell-substrate impedance readout, is able to monitor transient changes in cell-substrate adhesiveness as a result of U937 cell adhesion. The U937 cell adhesion to endothelial cells was induced by lipopolysaccharide (LPS) in a dose-dependent manner. Although the number of adherent U937 cells to the endothelial cells was verified by a standard assay, the adhesiveness of endothelial cells after addition of U937 cells was monitored by the RT-CES system. Furthermore, focal adhesion kinase protein decrease and F-actin rearrangement in endothelial cells were observed after addition of U937 cells. Our results indicated that the adhesion of U937 cells to LPS-treated endothelial cells reduced the cell adhesiveness to the substrate, and such reduction might facilitate infiltration of leukocytes.

Specific Expression of Optically Active Reporter Gene in Arginine Vasopressin‐Secreting Neurosecretory Cells in the Hypothalamic‐Neurohypophyseal System

The anti-diuretic hormone arginine vasopressin (AVP) is synthesised in the magnocellular neurosecretory cells (MNCs) in the paraventricular nucleus (PVN) and the supraoptic nucleus (SON) of the hypothalamus. AVP-containing MNCs that project their axon terminals to the posterior pituitary can be identified using immunohistochemical techniques with specific antibodies recognising AVP and neurophysin II, and by virtue of their electrophysiological properties. Recently, we generated transgenic rats expressing an AVP-enhanced green fluorescent protein (eGFP) fusion gene in AVP-containing MNCs. In this transgenic rat, eGFP mRNA was observed in the PVN and the SON, and eGFP fluorescence was seen in the PVN and the SON, and also in the posterior pituitary, indicating transport of transgene protein down MNC axons to storage in nerve terminals. The expression of the AVP-eGFP transgene and eGFP fluorescence in the PVN and the SON was markedly increased after dehydration and chronic salt-loading. On the other hand, AVP-containing parvocellular neurosecretory cells in the PVN that are involved in the activation of the hypothalamic-pituitary adrenal axis exhibit robust AVP-eGFP fluorescence after bilateral adrenalectomy and intraperitoneal administration of lipopolysaccharide. In the median eminence, the internal and external layer showed strong fluorescence for eGFP after osmotic stimuli and stressful conditions, respectively, again indicating appropriate transport of transgene traslation products. Brain slices and acutely-dissociated MNCs and axon terminals also exhibited strong fluorescence, as observed under fluorescence microscopy. The AVP-eGFP transgenic animals are thus unique and provide a useful tool to study AVP-secreting cells in vivo for electrophysiology, imaging analysis such as intracellular Ca(2+) imaging, organ culture and in vivo monitoring of dynamic change in AVP secretion.

Vegetation index analysis of multi‐source remote sensing data in coal mine wasteland

Thirty‐six soil samples were collected and their hyperspectral data used to calculate vegetation indices such as a normalised difference vegetation index (NDVT) and a difference vegetation index (DVT). These were evaluated for typical surface object features within the wastelands around Haizhou Opencast Coal Mine in Fuxin city. Aprincipal component analysis to the hyperspectral data was performed, and the result showed that the first and the second principal components satisfactorily accounted for the multi‐spectral image information. The panchromatic and multi‐spectral images of SPOT5 were then merged. The panchromatic image replaced the first principal component to improve spatial resolution of the image. In addition, the multispectral images and the NDVT image were classified into six types using the unsupervised classification method. The linear quantitative models were built up and the highest correlation coefficients were obtained between the hyperspectral vegetation index and the vegetation index data from the SPOT5 image. The results show that the hyperspectral data and remote sensing images can be used for quantitative estimation of soil nutrients in coal mine wasteland. They can also provide large area surface information for fast and effective decision making regarding revegetation and the monitoring of dynamic change.