Developments in methodological and technological aspects for biomolecular imaging are highly expected. We developed a novel design of split GFP and split luciferase; the principle is based on reconstitution of the split-reporter fragments when they are brought sufficiently close together. The usefulness of the split-reporter reconstitution has been demonstrated such as imaging of endogenous mRNA, protease activities, protein-protein interactions and protein transport into a specific organelle. This review introduces the basic principle of the reconstitution technology and its wider application in the fields of biology and basic medicine.
The rat represents an excellent mammalian model for broadening medical knowledge, and a wealth of information on its physiology has been obtained from its use as an experimental organism. Its ample body size allows various surgical manipulations that cannot be performed on a mouse. Many rat models mimic human diseases and have therefore been used in a variety of biomedical studies. In an effort to create specifically designed rats for new biomedical research and the field of regenerative medicine, we developed an engineered rat system on the basis of transgenic technology and have succeeded in establishing unique rats that possess genetically encoded color probes. In this review, we describe the potential of the photogenic transgenic rat that expresses fluorescent and/or luminescent proteins, and focus on the characteristic migration of MSCs to injury and tumor sites. In addition, we will discuss an efficient delivery method for targeting the injured site. Synergized with modern advances in optical imaging, the photogenic rat system provides innovative preclinical tools and a new platform on which to further our understanding of matters concerning stem cell biology.
High-dimensional medical image processing is explained by concretely introducing our researches in this paper. Highdimensional medical images become to be available by integrating a medical image with other ones and can provide quantitative and multilateral information to diagnose a patient's disease and decide therapy strategies by using image processing computers in recent years. The process of their clinical applications is similar to virtual reality systems' one and each of the processing techniques can be mapped on the transition diagram of virtual reality systems. We introduce our researches whose aims are to acquire high-dimensional medical images and integrate different modality images and explain high-dimensional image processing techniques by referring the processing stages of virtual reality computer systems.
The microsterolithography, which was one of the pioneering 3D-microfabrication technology, was developed by Ikuta in 1992. In microstereolithography, 3D structures were made by micro solidification of photo curable resin irradiated by ultraviolet laser. But commercial resin for microsterolithography had a lack of biocompatibility, so it was impossible to apply the microsterolithography to biomedical devices which touched directly cells or living organisms. In this paper, new type photo curable resins were not developed, but new methods applying cytocompatibility to commercial photo curable resin which stably had a precise resolution were challengingly investigated. The cytotoxicity was examined on various conditions, and the cytocompatibility was evaluated quantitatively. Eventually, parameters of the process that cell culture even in microstereolithographic wells could proliferate in equal rate with a commercial tissue culture polystylene dishes were discovered. This process did not limited a shape of structures. Moreover, although the transformation under heat-treatment of macro structures would happen, the advantage of scaling law for microstructures in which transformation under heat-treatment did not happen was taken. It was shown to applied to various photo curable resin. This process could be a basic key technology to accelerate expotentialy application researches in biochemistry, biology and biomedical field of microstereolithography.
In glioma resection, accurate detection of tumor region is absolutely imperative because most of malignant glioma has a property of infiltration to normal brain tissues. At the same time, since there is a high relationship between tumor resection rate and patient prognosis, it is required to extirpate tumor as much as possible. We developed an intraoperative spectrum measurement system for 5-aminolaevulinic acid induced protoporphrin IX (PpIX) fluorescence, which includes a semiconductor LASER, a CCD spectrometer, a personal computer and a fluorescence measurement probe which weight is about 25g. In the probe, fluorescence and an excitation light path are completely coaxial using a dichroic mirror. We evaluated performances of the probe using agar gels that have similar optical properties to brain tissues. Results showed that the probe possesses sufficient ability to measure PpIX fluorescence with a spatial resolution of about 0.8mm around working-distance. 7 examinee measured error distance from working distance to evaluate positional stability with handheld. The result showed that there were fluctuations less than 5mm from appropriate probe location, such a little positional error doesn' t affect fluorescence measurement.
The malpractice is a social issue. In this research, to propose the equipment that supported the medical treatment person's vein injection by showing the position of the injection, the design process was applied. The concept of the equipment became clear by the concept design sketch. Next, an infrared sensor and a printer device was selected by using the design sketch. A 45 mm in the radius arc shape was decided from the analysis of the shape of the equipment and the relation of the patient- system relation by prototyping. As a result of the an ergonomic analysis on the equipment operation, we could decide its shape inclining about 30 mm of the rear side of the equipment by 15 deg. It is thought that the maintenance of the quality of medical care can be achieved with vein injection support equipment. In addition, the application development of the equipment can be expected of management and the medical education of the medicine with the proposed equipment. On the other hand, it is thought that it leads to the presentation of an appropriate solution when medical equipment is developed by executing the design that considers the form.
Surgical mechatronics systems in a MRI environment promise a popular strategy for minimize invasive treatment. We developed an image guided MRI compatible manipulator with ultrasound motors used inside the MRI gantry. MRI compatibility is important in the development of a manipulator, since the effects of magnetic materials and the influence of electromagnetic wave leakage on MRI images should be considered. We evaluated the effect of electromagnetic waves on MR images and clarified the RF immunity level of the image. We also describe an electromagnetic wave shield required for MRI compatibility. We measured the leakage of electromagnetic waves as a novel way of evaluating MRI compatibility based on the results of our findings of RF immunity on images. We also quantified the MR compatibility of the manipulator based on MR images and electromagnetic wave measurements. The decrease in the signal-to-noise ratio (SNR) and distortion, caused by the manipulator inside a 0.2 T MRI gantry, and electromagnetic wave leakage to the actuator were evaluated. The results showed that MR images were only distorted for less than 2 pixels, and that the SNR decreased by 0.6%. Electromagnetic wave leakage at a resonance frequency band of 0.2 T MRI was undetectable. Therefore, the manipulator has high MRI compatibility and could be driven while acquiring MR images. This evaluation method is effective for developing novel MRI compatible mechatronics systems for use during the acquisition of MR images.