Shruti Dhingra, Masamune Morita, Tsuyoshi Yoda, Mun'delanji C. Vestergaard, T. Hamada, M. Takagi
{"title":"Dynamic transformation of a cell-sized liposome containing ganglioside","authors":"Shruti Dhingra, Masamune Morita, Tsuyoshi Yoda, Mun'delanji C. Vestergaard, T. Hamada, M. Takagi","doi":"10.1109/MHS.2011.6102232","DOIUrl":"https://doi.org/10.1109/MHS.2011.6102232","url":null,"abstract":"It is important to understand the physicochemical mechanisms that are responsible for the morphological changes in the cell membrane in the presence of various stimuli such as osmotic pressure. Role of micro domains such as lipid rafts in cellular processes is now beginning to unfold. In this study, we examined how constituent molecules affect the dynamical movement of liposomes. We used cell sized lipid vesicles to enable direct observation of these changes. We observed the effect of ganglioside (GM1) to osmotic stress induced membrane transformation in homogeneous and heterogeneous liposomes. Interestingly, it was observed that for the formation of sphero-stomatocyte there exists particular critical cut-off concentration. Also in the case of heterogeneous liposomes it was observed that at 10% molar ratio of GM1 almost all domains pinched out from the vesicles, forming their own homogeneous liposomes. Incorporation of GM1 into membrane leads to an increase of the line tension. Thus, necessary proteins can find themselves in one common raft and start the corresponding cascade of reactions.","PeriodicalId":286457,"journal":{"name":"2011 International Symposium on Micro-NanoMechatronics and Human Science","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129910950","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Masahiro Nakano, J. Teramoto, T. Shimada, Kaneyoshi Yamamoto, A. Ishihama
{"title":"Single molecule analysis of transcription factor-DNA complexes using atomic force microscopy","authors":"Masahiro Nakano, J. Teramoto, T. Shimada, Kaneyoshi Yamamoto, A. Ishihama","doi":"10.1109/MHS.2011.6102240","DOIUrl":"https://doi.org/10.1109/MHS.2011.6102240","url":null,"abstract":"Transcription of the Escherichia coli genome is under the control of approximately 300 species of transcription factor. However, the regulatory roles remain unidentified for about 100 species of the transcription factor. As an approach to identify their regulation modes, we analyzed the dynamics of DNA-transcription factor interactions using the atomic force microscopy (AFM). Here we examined the DNA-binding mode of two types of transcription factor in the presence and absence of RNA polymerase: a novel growth-specific nucleoid protein Dan (DNA-binding protein under anaerobic growth conditions); and global regulators, CRP (cAMP receptor protein) and Cra (catabolite repressor and activator), for control of transport and metabolism of carbon sources.","PeriodicalId":286457,"journal":{"name":"2011 International Symposium on Micro-NanoMechatronics and Human Science","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126554345","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Spheroid array formation by non-label cell manipulation using magneto-Archimedes effect","authors":"Y. Akiyama, K. Morishima","doi":"10.1109/MHS.2011.6102156","DOIUrl":"https://doi.org/10.1109/MHS.2011.6102156","url":null,"abstract":"This paper demonstrates spheroid array formation by a label-free three-dimensional (3D) cell assembly method which is based on the magneto-Archimedes effect. A paramagnetic salt (Gd-DOTA) is added to the culturing medium to enhance the diamagnetic property of the cells, by which label-free magnetic manipulation becomes possible. In this study, a chamber including cells suspended in the paramagnetic medium was placed on a magnet array, and spots with low (that is, almost zero) magnetic flux densities were formed on the array with the magnet array, on which the cells aggregated. These cell aggregates became spheroids after one day of culture. The result suggests that this 3D cell assembly method is a promising approach to construct micro 3D tissues in a closed small space.","PeriodicalId":286457,"journal":{"name":"2011 International Symposium on Micro-NanoMechatronics and Human Science","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125611694","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Giant liposomes as microcapsules with large trapping volumes: Downsizing through various membrane filters and analysis with a calcein quenching method","authors":"K. Tsumoto, Yuki Nakamura, M. Yamazoe, M. Tomita","doi":"10.1109/MHS.2011.6102228","DOIUrl":"https://doi.org/10.1109/MHS.2011.6102228","url":null,"abstract":"Giant unilamellar vesicles (GUVs), or giant liposomes, are very similar to actual cells about the size (∼1 – 100 µm); therefore, GUVs have much larger trapping volumes than conventional liposomes (large unilamellar vesicles, LUVs; ∼100 nm). Albeit having such large trapping volumes, GUVs are rarely employed as microcapsules for biomedical purposes because of their difficulties of the preparation in physiological buffer solutions in large quantities with the narrow size distributions. Here, we comparatively downsized giant liposomes by making them filtrated through various membrane filters including polycarbonate, polytetrafluoroethylene and nitrocellulose/cellurose acetate membranes, and measured their trapping volumes using a calcein quenching method. Any filters with around 1–5 µm pore sizes were useful to reduce the size from more than 10 µm to less than 5 µm, and their trapping volumes were estimated to be around ten times higher than those of 100-nm LUVs, which are reasonable values; however, somewhat large fractions of vesicles that were much smaller than the pore sizes remained in the sample.","PeriodicalId":286457,"journal":{"name":"2011 International Symposium on Micro-NanoMechatronics and Human Science","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130880219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Inchworm type microrobot using friction force control mechanisms","authors":"Yukihiro Itatsu, A. Torii, A. Ueda","doi":"10.1109/MHS.2011.6102192","DOIUrl":"https://doi.org/10.1109/MHS.2011.6102192","url":null,"abstract":"We studied inchworm type microrobots using piezoelectric elements. When the microrobot moves, friction between the microrobot and an operation surface disturbs the displacement of the microrobot. We propose the inchworm type microrobot which can control the friction force. The friction force is controlled by the use of squeeze film effect. The microrobot is composed of three friction force control mechanisms, two horizontal piezoelectric elements, and leaf springs. The friction force control mechanism is composed of a metal plate, a weight, and a stacked type piezoelectric element. When a vertical piezoelectric element vibrates vertically, the squeeze film effect occurs and the friction force control mechanism levitates. The leaf springs are used as vibration isolators. The friction force control mechanism levitating in air moves by the push and pull of the horizontal piezoelectric elements. In this study, first, the height of a bottom plate of the levitation mechanism is measured. Then we changed the control frequency and waveforms, and measured the velocity of the microrobot.","PeriodicalId":286457,"journal":{"name":"2011 International Symposium on Micro-NanoMechatronics and Human Science","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132925366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yusuke Kiyama, Yoshiyuki Tominaga, T. Kanda, K. Suzumori, Yoshiaki Yamada, Norihisa Seno
{"title":"Micro droplet generation using micropore plates oscillated by ultrasonic torsional transducers","authors":"Yusuke Kiyama, Yoshiyuki Tominaga, T. Kanda, K. Suzumori, Yoshiaki Yamada, Norihisa Seno","doi":"10.1109/MHS.2011.6102165","DOIUrl":"https://doi.org/10.1109/MHS.2011.6102165","url":null,"abstract":"Monodisperse droplets have been an important subject in fields such as electronic materials, cosmetics productions and medical science. The goal of this study is to generate micro and uniform droplets in various viscosity liquids by using a micropore plate oscillated by an ultrasonic torsional transducer. When the micropore plate was not oscillated, droplets were generated irregularly. On the other hand, when the micropore plate was oscillated by the ultrasonic torsional transducer, droplets were generated regularly by ruffling liquid surface. We have generated droplets in the air by using pure water and silicone oil of various viscosities and evaluated droplets. We have designed the ultrasonic torsional transducer and a droplet generation device to apply a high pressure for the use of higher viscosity liquids. We have succeeded in generating droplets by using pure water when we used the ultrasonic torsional transducer. The average diameter of droplets was 30.0µm and the standard deviation was 0.98. We have also succeeded in generating 50cSt silicone oil droplets using the droplet generation device. The average diameter of droplets was 98.0µm and the standard deviation was 0.76.","PeriodicalId":286457,"journal":{"name":"2011 International Symposium on Micro-NanoMechatronics and Human Science","volume":"103 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132936832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
K. Matsuura, Koyo Watanabe, Mieko Kodama, Yuka Kuroda, K. Naruse
{"title":"Development of observation system to investigate both intracellular calcium concentration and mechanical stimuli to mammalian embryos","authors":"K. Matsuura, Koyo Watanabe, Mieko Kodama, Yuka Kuroda, K. Naruse","doi":"10.1109/MHS.2011.6102167","DOIUrl":"https://doi.org/10.1109/MHS.2011.6102167","url":null,"abstract":"Using an air-actuating device, we investigated the cellular response to mechanical stimuli (MS) in mouse blastocysts. Both MS and intracellular calcium concentration ([Ca2+]i) were quantified based on time-resolved confocal microscopy images in the polydimethylsiloxane (PDMS) microfluidic channels by deforming a 0.1-mm membrane. [Ca2+]i was measured in a stained mouse embryo with Fluo-4 AM using confocal fluorescence microscopy. We captured a z-series stack of sections encompassing the entire embryo. When translocation velocities of the embryo and shear stress were 40 µm/s and 0.01 dyne/cm2, respectively, a 10% increase in the sum of fluorescent intensities (FI) was observed. When blastocysts were compressed, FI also increased in response to the applied MS. Compressive force estimated from the shape of the blastocysts was approximately 0.5–2.0 µN according to a force deformation curve for the mouse embryo. The average FI and sum of FIs increased by a factor of 1.1–1.2 times compared with those observed before MS. The increase in the sum of FI indicated that enhancement of [Ca2+]i would be induced by these MS.","PeriodicalId":286457,"journal":{"name":"2011 International Symposium on Micro-NanoMechatronics and Human Science","volume":"420 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133021850","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R. Takeuchi, K. Fukumori, Katsuhisa Sakaguchi, Y. Terajima, Tatsuya Shimizu, T. Okano, M. Umezu
{"title":"Novel device for transplantation of cell sheet and evaluation of thin polymer films by atomic force microscopy","authors":"R. Takeuchi, K. Fukumori, Katsuhisa Sakaguchi, Y. Terajima, Tatsuya Shimizu, T. Okano, M. Umezu","doi":"10.1109/MHS.2011.6102201","DOIUrl":"https://doi.org/10.1109/MHS.2011.6102201","url":null,"abstract":"Cell therapy is expected to a new tool to treat refractory diseases. In heart regeneration, it has been firstly conducted with needle injection of cell suspensions. Recently, cell sheet engineering emerged as another method of cell therapy. Cell sheet is prepared with a temperature responsive dish by temperature reduction. It is a thin-patch-like tissue construct and its thickness is several tens of micrometers. It is composed of cells and intrinsic extra cellular matrix only. The transplantation of the cell sheet has been already conducted in animal experiments and even in clinical trials. The cell sheet is transplanted at the surface of the heart, but it is difficult to transplant the cell sheet under the beating heart. To overcome this difficulty, we designed a device that was composed of two thin polymer films that have different friction. The films were made of polyurethane, polyethylene, or polypropylene. The cell sheet was set up on the device by sandwiching it with the less frictional film and the more frictional film. In this paper, using two different films having the different friction, the cell sheet was successfully transplanted to the static round polymer surface, the harvested heart, and even the beating heart of pig by removing the films step by step using the difference in friction. Also, surface properties such as friction, adhesion force and roughness of the films were studied by an atomic force microscopy (AFM). From the results of the study, the friction of the film was found to be likely proportional to the adhesion force and the inverse of roughness.","PeriodicalId":286457,"journal":{"name":"2011 International Symposium on Micro-NanoMechatronics and Human Science","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115012126","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Virtual building blocks using a 2.5D-display generating of tactile and force sensations","authors":"S. Tsuboi, M. Ohka","doi":"10.1109/MHS.2011.6102219","DOIUrl":"https://doi.org/10.1109/MHS.2011.6102219","url":null,"abstract":"To develop new equipment for virtual reality, we study a combined display capable of stimulating the muscles and tendons of the forearms and tactile receptors in fingers to investigate tactile and force effects on simultaneous presentation. We arranged the handle of the display like a mouse so that anyone could comfortably use it without a priori knowledge. The present display is comprised of a master arm with a tactile display with a 4-by-12 array of stimulus pins driven by micro-actuators and an articulated manipulator to stimulate the muscles and tendons of the forearms and tactile receptors in fingers. Vertical movement of the virtual tactile pad in the virtual world is controlled in proportion to compressive force applied on the display pad, so that operators don't get tired during manipulations in 3D-space because their hands are supported by the manipulator. The compressive force is measured by a pressure sensor installed under the actuator array. Operators can work in 3D-space in spite of their manipulations in 2.5D-space. Evaluation experiments are performed using the display to verify its presentation capability. In the experiments, subjects try to build up virtual blocks in a line using the display. A precise building task is impossible for the force-only display because of no relative motion between the hands and the blocks, while the building task is completed by the combined display of tactile and force sensations with higher precision.","PeriodicalId":286457,"journal":{"name":"2011 International Symposium on Micro-NanoMechatronics and Human Science","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121994814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Fabrication of a dynamic compression stimulus microdevice to cells for evaluating real-time cellular response","authors":"Y. Nakashima, Y. Yang, K. Minami","doi":"10.1109/MHS.2011.6102212","DOIUrl":"https://doi.org/10.1109/MHS.2011.6102212","url":null,"abstract":"This paper presents a microdevice intended to evaluate the real-time response of cells to compression stimulus for dynamic cell differentiation induction. This device was realized by the micro three-dimensional structure fabrication process using multiple exposures to photoresist. The microdevice consists of microchannels, a pressure inlet port, cell culture chambers and a diaphragm on the culture chamber for applying compressive pressure to cells. Compression stimulus to cells can be controlled by regulating of the diaphragm expansion with the pressure control. This device can make it to observe the behavior of cellular response stimulated by compressive pressure because this device is made of transparency materials and stimulates the cells without deforming the cell culture surface observed by an optical microscope. We demonstrated the validity of the fabrication process, and evaluated the performance of the test device. As a result of operation test, the diaphragm was deformed quickly by applied negative/positive pressure, and the diaphragm displacement became larger with increasing of the applied pressure. These results indicate that this device can control the intensity and the profile of cell stimulus by regulating the applied pressure.","PeriodicalId":286457,"journal":{"name":"2011 International Symposium on Micro-NanoMechatronics and Human Science","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117081549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}