Locally applied cilostazol suppresses neointimal hyperplasia by inhibiting tenascin-C synthesis and smooth muscle cell proliferation in free artery grafts

AbstractObjectiveAccumulation of smooth muscle cells and extracellular matrix in the intima of artery bypass grafts induces neointimal hyperplasia, resulting in graft failure. We investigated the inhibitory effect of locally applied cilostazol, an inhibitor of cyclic adenosine monophosphate phosphodiesterase III, on neointimal hyperplasia and the role of tenascin-C synthesis and smooth muscle cell proliferation in free artery grafts.Methods and resultsWe established a distal anastomotic stricture model of free artery graft stenosis using rat abdominal aorta. In this model, neointimal hyperplasia was observed not only in the distal anastomotic site but also in the graft body at postoperative day 14 and was markedly progressed at day 28. Strong expression of tenascin-C was found in the media and neointima of the graft body. When cilostazol was locally administered around the graft using Pluronic gel, neointimal hyperplasia of the graft was significantly suppressed in comparison with gel-treated control graft. The mean neointima/media area ratio was reduced by 86.6% for the graft body and by 75.8% for the distal anastomotic site versus the control. Cilostazol treatment decreased cell proliferation and tenascin-C expression in the neointima. In an in vitro experiment using cultured smooth muscle cells isolated from rat aorta, cilostazol completely suppressed the tenascin-C mRNA expression induced by platelet-derived growth factor-BB.ConclusionA single topical administration of cilostazol may suppress neointimal hyperplasia by inhibiting cell proliferation and tenascin-C synthesis in free artery grafts, presenting the potential for clinical use in vascular surgery

Adenovirus vector-mediated assay system for hepatitis C virus replication

The efficient delivery of the hepatitis C virus (HCV) RNA subgenomic replicon into cells is useful for basic and pharmaceutical studies. The adenovirus (Ad) vector is a convenient and efficient tool for the transduction of foreign genes into cells in vitro and in vivo. However, an Ad vector expressing the HCV replicon has never been developed. In the present study, we developed Ad vector containing an RNA polymerase (pol) I-dependent expression cassette and a tetracycline-controllable RNA pol I-dependent expression system. We prepared a hybrid promoter from the tetracycline-responsive element and the RNA pol I promoter. Ad vector particles coding the hybrid promoter-driven HCV replicon could be amplified, and interferon, an inhibitor of HCV replication, reduced HCV replication in cells transduced with the Ad vector coding HCV replicon. This is the first report of the development of an Ad vector-mediated HCV replicon system

The relationship between fatty acid composition of dinoflagellate and environmental stresses

第2回極域科学シンポジウム　共通セッション「海氷圏の生物地球化学」 11月16日（水） 統計数理研究所 3階リフレッシュフロ

Bacterial Long-Chain Polyunsaturated Fatty Acids: Their Biosynthetic Genes, Functions, and Practical Use

The nutritional and pharmaceutical values of long-chain polyunsaturated fatty acids (LC-PUFAs) such as arachidonic, eicosapentaenoic and docosahexaenoic acids have been well recognized. These LC-PUFAs are physiologically important compounds in bacteria and eukaryotes. Although little is known about the biosynthetic mechanisms and functions of LC-PUFAs in bacteria compared to those in higher organisms, a combination of genetic, bioinformatic, and molecular biological approaches to LC-PUFA-producing bacteria and some eukaryotes have revealed the notably diverse organization of the pfa genes encoding a polyunsaturated fatty acid synthase complex (PUFA synthase), the LC-PUFA biosynthetic processes, and tertiary structures of the domains of this enzyme. In bacteria, LC-PUFAs appear to take part in specific functions facilitating individual membrane proteins rather than in the adjustment of the physical fluidity of the whole cell membrane. Very long chain polyunsaturated hydrocarbons (LC-HCs) such as hentriacontanonaene are considered to be closely related to LC-PUFAs in their biosynthesis and function. The possible role of LC-HCs in strictly anaerobic bacteria under aerobic and anaerobic environments and the evolutionary relationships of anaerobic and aerobic bacteria carrying pfa-like genes are also discussed

Mobile phone based acoustic localization for wireless sensor networks

In wireless sensor networks, localization techniques are required for finding physical location of the sensor nodes. Most of the existing 2D and 3D localization schemes are reference based. Finding physical locations of sensor nodes in an application field with only 2D or 3D physical topology map or logical topology map is arduous and tedious. This paper refers to mobile phone based acoustic localization technique for wireless sensor networks, which can be used along with physical topology map or logical topology map. In our proposed method, deployer searches the sensor node by using Doppler effect of acoustic wave, which is generated by his mobility. The proposed method helps in quick localizing of the sensor nodes without consuming much time and it has been implemented, tested by using mobile phone and HTH motes, the in-house developed sensor nodes

Novel Carotenoid-Based Biosensor for Simple Visual Detection of Arsenite: Characterization and Preliminary Evaluation for Environmental Application▿ †

A novel whole-cell arsenite biosensor was developed using the photosynthetic bacterium Rhodopseudomonas palustris no. 7 and characterized. A sensor plasmid containing the operator-promoter region of the ars operon and arsR gene from Escherichia coli and the crtI gene from R. palustris no. 7 was introduced into a blue-green mutant with crtI deleted, R. palustris no. 711. The biosensor changed color in response to arsenite, and the change was obvious to the naked eye after 24 h without further manipulation. Real-time reverse transcription-PCR showed that the crtI mRNA was induced 3-fold at 3 h and 2.5-fold at 6 h after addition of 50 μg/liter arsenite compared with the no-arsenite control, and consistent with this, the relative levels of lycopene and rhodopin also increased compared with the control. Colorimetric analysis of the bacteria showed that the hue angle had clearly shifted from green-yellow toward red in an arsenic dose-dependent manner at 24 h after arsenite addition. This obvious shift occurred irrespective of the culture conditions before arsenite was added, indicating that the color change of the biosensor is stable in water samples containing various concentrations of dissolved oxygen. Finally, assays using samples prepared in various types of mineral water indicated that this biosensor could be used to screen groundwater samples for the presence of arsenite in a variety of locations, even where electricity is not available