Expression of tropomyosin alpha 4 chain is increased in esophageal squamous cell carcinoma as evidenced by proteomic profiling by two-dimensional electrophoresis and liquid chromatography-mass spectrometry/mass spectrometry

To identify proteins associated with esophageal carcinogenesis, we performed protein profiling of 16 esophageal squamous cell carcinomas (ESCCs) and paired noncancerous tissues by 2-DE and MS/MS. In cancerous tissues, three spots showed significant up-regulation in the amount of protein, while eight spots were significantly down-regulated. The identities of the spots were determined by PMF with LC-MS/MS and were confirmed by immunoblotting. The up-regulated proteins were tropomyosin alpha 4 chain, transgelin, and pyruvate kinase. The down-regulated proteins were serum albumin precursor, isoforms of annexin A1, tropomyosin beta chain, 14-3-3 protein sigma, and isoforms of serotransferrin precursor. In all 16 cases, up-regulation of the tropomyosin alpha 4 chain was confirmed by immunoblotting. Localization of the tropomyosin alpha 4 chain in ESCC cells and adjacent fibroblasts was confirmed by immunohistochemistry.     

Important options available — from start to finish — for translating proteomics results to clinical chemistry

In the realm of clinical chemistry, the field of clinical proteomics, that is, the application of proteomic methods for understanding mechanisms and enabling diagnosis, prediction, measurement of activity, and treatment response in disease, is first and foremost a discovery and research tool that feeds assay development downstream. Putative new assay candidates generated by proteomics discovery projects compete with well-established assays with known indications, well-described performance, and of known value in specific clinical settings. Careful attention to the many options available in the design, execution, and interpretation of clinical proteomics studies is thus necessary for translation into clinical practice. We here review and discuss important options associated with clinical proteomics endeavors stretching from the planning phases to the final use in clinical chemistry.     

二维自适应有限元网格生成

自适应有限元网格生成是基于误差估计，自动进行有限元网格优化的一种策略。本文提出了一种基于单元误差估计的二维自适应有限元网格生成算法，并讨论了其实现过程。     

The Story of the GeoToolKit—An Object-Oriented Geodatabase Kernel System

The quickly increasing number of spatio-temporal applications in fields like environmental monitoring, geology and mobile communication is a new challenge to the development of geodatabases. However, the query functionality of today's geo-information systems is still limited to the thematic attributes of spatial objects and to spatial 2-D objects. This article reports on GeoToolKit, an object-oriented geo-database kernel system developed at Bonn University to support 3-D/4-D geological applications. GeoToolKit is not a GIS-in-a-box package, but rather a library of C ++ classes that allows the incorporation of spatio-temporal functionality within an application. Being a component toolkit, it encourages the development and deployment of re-usable and open software. The history, concepts and implementation of GeoToolKit are discussed in detail. Performance tests underline the practicability of the concepts. Extensions to and experiences with GeoToolKit applications like GeoStore, GeoWeb and WellStore are presented. Finally, we give an outlook on our future research introducing GeoToolKit as a 3-D/4-D database component within a network of distributed and mobile geo-information services.     

A catalogue of proteins released by colorectal cancer cells in vitro as an alternative source for biomarker discovery

Improved methods for the early diagnosis of colorectal cancer by way of sensitive and specific tumour markers are highly desirable. Therefore, efficient strategies for biomarker discovery are urgently needed. Here we present an approach that is based on the direct experimental access to proteins released by SW620 human colorectal cancer cells in vitro. A 2-D map and a catalogue of this subproteome - here termed the secretome - were established comprising more than 320 identified proteins which translate into approximately 220 distinct genes. As the majority of the secretome constituents were nominally cellular proteins, we directly compared the secretome and the total proteome by 2-D-DIGE analysis. We provide evidence that unspecific release through cell death, classical secretion, ectodomain shedding, and exosomal release contribute to the secretome in vitro, presumably reflecting the mechanisms in vivo which lead to the occurrence of tumour-specific proteins in the circulation. These data together with the fact that the SW620 secretome catalogue, as presented here, does comprise a large number of known and novel biomarker candidates, validates our approach to isolate and characterize the tumour cell secretome in vitro as a rich source for tumour biomarkers.     

基于平面图像实现三维仿真场景的技术方法研究

利用Windows操作系统平台正的DirectX多媒体接口技术,本文提出了利用平面图像实现三维仿真场景的相关实用技术方法。