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Purpose: Tetrandrine (Tet), a bis-benzylisoquinoline alkaloid that was isolated from the dried root of Hang-Fang-Chi (Stephania tetrandra S. Moore), is well known as processing a marked antitumor effect in vitro and in vivo. The aim of this study was to assess the interaction between tetrandrine and chemotherapeutic agents widely used in gastric cancer treatment, and to investigate the influence of tetrandrine on chemotherapeutic agent-associated gene expression and apoptosis., Methods: Synergistic interaction on human gastric cancer BGC-823 and MKN-28 cells was evaluated using the combination index (CI) method. The double staining with both Annexin-V-FITC and PI was employed to distinguish the apoptotic cells from living cells. Expression of chemotherapeutic agent-associated genes, i.e., excision repair cross-complementing 1 (ERCC1), thymidylate synthase (TS), class III beta-tubulin (beta-tubulin III) and tau, of BGC-823 cells with or without tetrandrine treatment were measured by real-time quantitative PCR., Results: Tetrandrine had a synergistic effect on the cytotoxicity of chemotherapeutic agents in both two gastric cancer cell lines. The combination of tetrandrine and chemotherapeutic agents could also induce apoptosis in a synergistic manner. Tetrandrine could suppress the mRNA expression of ERCC1, TS, beta-tubulin III and tau. Most prominently, ERCC1, TS and beta-tubulin III mRNA levels were markedly suppressed at 0.29-, 0.12- and 0.60-fold, respectively, by the presentation of tetrandrine., Conclusion: Tetrandrine appears a promising candidate for combining with three chemotherapeutic agents. The possible mechanisms might be the synergistic apoptotic effect and the downregulation of chemotherapeutic agent-associated genes.

Targeted delivery of antitumor drugs triggered by hyperthermia has significant advantages in clinical applications, since it is easy to implement and side effects are reduced. To release drugs site-specifically upon local heating often requires the drugs to be loaded into a thermosensitive polymer matrix with a low critical solution temperature (LCST) between 37 and 42 degrees C. However, the LCSTs of most thermosensitive materials were below 37 degrees C, which limits their application in clinic because they would precipitate once injected into human body and lost thermal targeting function. Herein, we prepared a novel thermosensitive copolymer (poly(N-isopropylacrylamide-co-acrylamide)-b-poly (DL-lactide)) that exhibits no obvious physical change up to 41 degrees C when heated. Docetaxel loaded micelles made of such thermosensitive polymer were prepared by dialysis method and the maximum loading content was found to be up to 27%. The physical properties, such as structure, morphology, and size distribution of the micelles with and without docetaxel were investigated by NMR, X-ray diffraction, dynamic light scattering, atomic force microscopy, etc. The efficacy of this drug delivery system was also evaluated by examining the proliferation inhibiting activity against different cell lines in vitro. After hyperthermia, the cytotoxicity of docetaxel-loaded micelles increased prominently. Our results demonstrated that this copolymer could be an ideal candidate for thermal targeted antitumor drug delivery., ((c) 2007 Wiley Periodicals, Inc.)

Most traditional designs of otoacoustic emissions (OAEs) detecting system adopt the model of "sensor + sound signal sampler / generator + personal computer". This kind of model has shortcomings that it is apt to introduce exterior noises and lacks system integration, which often brings much inconvenience into the process of measuring. There are also some other OAEs detecting systems that use a digital signal processor (DSP) to collect and process the OAEs response signals, but a DSP is not a best choice to perform as a control unit on a portable device for that they usually do not have many peripheral hardware interfaces and are relatively demanding in cost. Different from the fore-mentioned two kinds of control unit, ARM is a kind of elegant new design, with a complete set of common system peripherals, to provide hand-held devices with low-cost and high-performance microcontroller solution in small die size. In this article, a novel design of a highly integrated and network-accessed portable otoacoustic emissions detecting system based on ARM (mainly for TEOAE and DPOAE) is presented. In addition, a comparison of the differences in the system's real-time performance based on different microcontroller units is provided to justify the use of ARM.

The biomedical imaging and image processing course in Shanghai Jiao Tong University is a core course in the Department of Biomedical Engineering. We have taken many measures in the course system, student practice, classroom teaching, and active and creative learning. The effectiveness of the measures and the results are reported. The course is highly appraised by teachers and students and won many awards. The measures and experience of our course may enrich the teaching and learning method bank in Biomedical Engineering (BME) education.

There are many noise disturbances in ultrasound image, and the surgical treatments are in great request for medical image, but the three dimensional image based on traditional surface graphics method cannot satisfy the request. Nevertheless, researches on visualization technology involves the denotation, operation and vision of the volume data the object contains, and the volume data contains ampler and more intact information than does the surface, therefore visualization technology will be widely used in the field of three dimensional medical image.