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Copyright of Journal of the Society of Japanese Women Scientists / Nihon Josei Kagakusha no Kai Gakujutsushi is the property of Society of Japanese Women Scientists and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Optical measurement techniques have many features suitable for biomedical applications. This reviewpaper summarizes the fundamental principles and techniques of optical measurement with a focus on biomedical applications. First, the physical properties and parameters of light are presented. Next, the basic elements of optical measurement, such as units, light sources, photodetectors, image sensors, lenses, optical fibers, integrating spheres, and lock-in amplifiers, are described. Then, the basic techniques of optical measurement, such as spectroscopy, optical interferometry, time-resolved measurement, and scattering measurement, are explained. Examples of applied optical measurement are introduced as laboratory test instruments, pulse oximeters, optical fiber sensors, structural imaging, and functional imaging. [ABSTRACT FROM AUTHOR]

Stratified flow in liquid-liquid two-phase flow of water-perfluorocarbon (PFC) system is expected to be utilized in biomedical engineering. In particular, the stratified flow is considered to be used for the research of cell sorting and transporting method for cell treatment process of transplantation. This method can transport cells without any damages and supply oxygen to cells. However, studies on liquid-liquid two-phase flows have been conducted mainly in oil-water systems, and there have been few studies under the condition where water is the upper layer. There is also little research on the shape of the interface for stratified flow, which is required for living cells sorting. In this study, we investigated the conditions for the formation of stratified flow in a waterPFC system using experimental and numerical simulation. The volume of fluid (VOF) method was employed to predict the interface shape of the stratified flow depending on the Weber number and the Eötvös number. As a result, the formation of stratified flow was observed in the range of We≥1 and in the range of We≥0.05 and Eo≥4. From the analysis, no significant difference in the interface shape was observed in this experimental condition range. Therefore, we can employ this flow system for cell treatment process to develop novel devices for cell therapy. [ABSTRACT FROM AUTHOR]

A novel method to measure the deformation of a urethane-foam object using an X-ray computed tomography (X-ray CT) technique was proposed and examined. The proposed method is made up of following two steps. First, X-ray sensitive ‘contrast media’ were drawn in lattice-like manner on top and bottom surfaces and internal planes of urethane-foam, which enabled visualization of the drawn positions in CT images. Second, position data of contrast media were then converted into the numerical values in a prescribed coordinate to measure the deformation. It was found that the contrast media successfully visualized outer and internal displacement with the urethane-foam deformation, and the comprehensive error of measurement was 0.3 mm in root mean square. As a trial for further practical purpose, the deformation of the urethane-foam mattress with a human-body model on it was measured using this method. A urethane-foam mattress with contrast media was prepared, a human trunk model was set on the mattress, and the mattress with the model was subjected to X-ray CT. The deformation state at surface of, and especially inside of, the mattress could be visualized and measured. We concluded that the proposed method could bring us an information on deformation state of the urethane-foam and the urethane-foam mattress as numerical values.

Control technique of orientation of a biological cell is expected to be applied to tissue engineering. It is known that morphology of the scaffold affects the cell behavior. For example, the micro stripe pattern can control cell orientation. The effect of aspect ratio of the micro checkered pattern on cell orientation has been investigated in the present study. The dimension of each unit of the micro checkered pattern is as follows: the length is 10 μm, and the height is 0.7 μm. Variation has been made on the width of the micro pattern: 5 μm (A), 8 μm (B) and 10 μm (C). Each type of repeated micro pattern was formed in the square area of 500 μm × 500 μm. The micro pattern was made of the negative photoresist material (SU-8 2) coated on a glass plate by the photolithography technique. C2C12 (mouse myoblast cell) was cultured for 24 hours on the micro pattern. The angle between the longitudinal axis of each cell and the width of the micro pattern was measured on the microscopic image. In each pattern, the average angle was as follows: 62.8 degrees on A, 50.2 degrees on B and 41.2 degrees on C. The experimental results show that the aspect ratio of micro checkered pattern controls cell orientation.

Separation technique of the circulating tumor cell (CTC), which would be a sample for diagnostics of cancer, is important. In the present study, a micro flow device, which has gaps between micro-cylinders, has been fabricated by photolithography technique to distinguish between cancer cells and red blood cells. Two kinds of cells were used in the test: Hepa1-6 and swine red blood cell. The mean diameters of two kinds of cells measured by ImageJ were 21 μm and 6 μm. Variation was made on the dimension of the gap: 10, 15, 20 and 25 μm. The micro cylindrical pattern was fabricated on the slide glass with a photomask of titanium film. The negative resist material (SU-8) was coated on the glass plate to make the 60 μm height of the micro cylindrical pattern. A micro flow channel was made between the glass plate with the micro cylindrical pattern and the flat polydimethylsiloxane (PDMS) disk. Swine blood was diluted 100 times by the saline solution. The concentration of Hepa1-6 was adjusted to 5000 cells/ml by the physiological saline solution or by the swine blood. The cell suspension of 30 μl was injected into the channel by a micropipette, and the trap rate at the gap of the micro pattern was measured. The experimental result shows that trap rates of micro cylindrical pattern gap of 10, 15, 20 and 25 μm are 100, 80, 37 and 26%, respectively. Most of the swine red blood cells can pass through the 10 μm gap. The result shows that the microchannel device developed in the present study is effective for the separation of the CTC.

Acetabular dysplasia describes an underdeveloped or shallow, upwardly sloping acetabulum, which may occur with varying degrees of deformity of the proximal femur such as excessive femoral neck anteversion, coxa valga or femoral neck cam deformity. Numerous stabilising procedures have been described, one of the first being the shelf acetabuloplasty. Shelf procedure improves coverage of the femoral head, without changing orientation of the acetabulum.This will improve the range of movement in the hip and protect the femoral head. In this study, we investigated the effect of shelf acetabuloplasty for load distribution of acetabular roof and femoral head using the finite element method (FEM). A three-dimensional (3D) generic musculoskeletal model was developed based on computed tomographic (CT) to estimate joint reaction force. As a result, we funded load distribution decreased on the top of the ace tabular rim and femoral head. Shelf acetabuloplasty may effective procedure for acetabular dysplasia because of improvement for load distribution.

Biomedical engineers have traditionally developed technologies in response to the needs of the developed world's medical community. Because "smart" polymers can respond to small changes in external stimuli with large discontinuous changes in their physical properties, development of smart polymer-based technologies will impact medical treatment in multiple ways, providing health delivery services and new options for conventional therapies, particularly in the resource-limited environments such as in developing world. We report here smart polymer technologies for global health, which make it possible to develop point-of-care diagnostics or systems with accurate 'on-off' switching to display their highly desirable properties without the requirement of an external power supply. [ABSTRACT FROM AUTHOR]

Progress in medical care strongly depends on the development of pharmaceutical and medical technologies. Multi-disciplinary care by a medical team is required for the diversity of medical care. "Clinical engineering technician (CET) " is one of the national medical licenses in Japan. Many CETs are engaged in blood purification therapies. Team medical care, involving medical doctors, nurses, CETs, etc., in the hemodialysis field is useful for the early detection of complications in dialysis patients and provision of appropriate treatments. In some medical facilities, for example, progressive approaches such as appropriate nutritional guidance by a dietitian or exercise therapy by a physical therapist are practiced in advance. Clinical laboratory technologists (CLTs), furthermore, play an important role in team medical care for dial- ysis therapy. They can use ultrasonic equipment for vascular access management. Based on the results of the ABI and SPP measurements by CLTs, medical doctors can diagnose PAD in dialysis patients. [Review].

It has been 22 years since clinical engineers first made their appearance as experts in medical equipment used to save patients' lives. At that time, legal revisions, ministerial ordinances, and regulations were established, with the final step awaiting a change in the medical environment. The pressing problem of a serious shortage of physicians is now apparent. The role of clinical engineers can be seen as providing one solution to this problem from the viewpoint of team medical treatment. A study is currently underway to determine how clinical engineers, who are co-medical members of the team, might also be expected to contribute a type of new militant power" to the medical field. In current surgical procedures, clinical engineers are necessary to operate various high-risk therapeutic equipment such as therapeutic surgical and life support devices. Clinical engineers work not only in the control of life support devices but also in expanded fields in perioperative care. A revision of the clinical engineer's role in perioperative care and work guidelines is needed so that their fundamental strengths can promote such goals as improved medical safety and a reduction in the burden on physicians and other medical personnel.

Recently, medical applications of nanotechnology have received much attention. Among them, advances in polymer chemistry have significantly contributed to this field. Here, we review nano-engineering of functional polymers for diagnostic and therapeutic purposes, which have been carried out mainly by our group. Functional polymer-coated nanoparticles can be used for quick detection of biomarkers and DNA separation. Multiarray of hepatocyte spheroids on a microfabricated polymer-brush surface can maintain the hepatocyte viability and liver-specific functions, offering a new high-throughput screening method of pharmacologically and toxicologically active compounds for drug discovery. Polymeric micelles are promising drug carriers, of which the critical parameters such as the size, drug loading and release can be controlled by engineering the constituent block copolymers. Thus, polymeric nano-device will be the leading technology in this field.

During the past three decades, significant advances have been made in the field of transplantation. However, clinical obstacles such as donor scarcity, cost, infection and life-long immunosuppression(especially within the pediatric age group) have become the major limitations for organ transplantation. This article discusses the recent progresses as well as the remaining challenges in tissue engineering that may enable such technology to replace organ transplantation. Additionally, we describe a practical method for tissue engineering in the field of cardiovascular surgery.

Human genome project will be completed in 2003 and we will soon obtain the information of the whole DNA sequence of the human genome. This should affect the therapy of progressive renal diseases since we have no effective remedy to cure the renal diseases. Gene therapy, renal engineering and generation of new drug can be achieved by using the information of human genome. In this context, we described our recent endeavors concerning the gene therapy of transplant kidney, seeking the renal stem cells and reprogramming factors, and exploring genes related to renal fibrosis. Completion of bioinformatics, can facilitate the above post-genome project.

Methods for the selective determination of organic compounds in biological fluids, such as blood, are very important in clinical analyses. Most analyses of organic compounds can be performed by spectrophotometric methods, based on specific enzyme-catalyzed reactions. However, because of the complicated procedure, these methods cannot be applied directly to bed-side monitoring. Alternatively, biosensors based on enzymes and electrochemical transducers possess excellent sensitivity for biological substrates and can determine a single compound in a biological fluid directly without need for a prior separation step. Therefore, in the past several years, many kinds of biosensors have been developed, and implantable microbiosensors for a body organ have also been reported.