Reductive removal of selenate (VI) in aqueous solution using rhodium metal particles supported on TiO.

Selenium and its compounds in high concentration are toxic for humans, especially selenate (VI) is the most toxic due to its high solubility in water. To promote the reductive reaction of Se(vi) to Se(iv) or Se(0), which is relatively easy to remove in water, noble metal particles were added as reaction sites with a reductant. The highest removal performance of selenate in aqueous solution was achieved using rhodium particles supported on TiO (Rh/TiO).

A bioartificial liver device based on three-dimensional culture of genetically engineered hepatoma cells using hollow fibers.

The bioartificial liver (BAL) device is an extracorporeal liver support system incorporating living hepatocytes. A major problem in BAL device development is to obtain a high number of functional cells. In this study, we focused on a genetically engineered mouse hepatoma cell line, Hepa/8F5, in which elevated liver functions are induced via overexpression of liver-enriched transcription factors activated by doxycycline (Dox) addition.

Effects of viscoelasticity on shear-thickening in dilute suspensions in a viscoelastic fluid.

We investigate previously unclarified effects of fluid elasticity on shear-thickening in dilute suspensions in an Oldroyd-B viscoelastic fluid using a novel direct numerical simulation based on the smoothed profile method. Fluid elasticity is determined by the Weissenberg number Wi and by viscosity ratio 1 - β = ηp/(ηs + ηp) which measures the coupling between the polymer stress and flow: ηp and ηs are the polymer and solvent viscosity, respectively. As 1 - β increases, while the stresslet does not change significantly compared to that in the β → 1 limit, the growth rate of the normalized polymer stress with Wi was suppressed.

Expansion and differentiation of human iPS cells in a three-dimensional culture using hollow fibers and separation of the specific population by magnetic-activated cell sorting.

In order to employ pluripotent stem cells in the field of regenerative medicine, it is necessary to establish a large-scale culture system for cell differentiation. We have developed a novel three-dimensional method for culturing human induced pluripotent stem (iPS) cells, using hollow fibers (HFs). The cells immobilized inside HFs can proliferate and form multicellular aggregates, capable of achieving a high cell density and promoting further spontaneous cell differentiation.

Evaluation of hollow fiber culture for large-scale production of mouse embryonic stem cell-derived hematopoietic stem cells.

Hematopoietic stem cells (HSCs) have the ability to differentiate into all types of blood cells and can be transplanted to treat blood disorders. However, it is difficult to obtain HSCs in large quantities because of the shortage of donors. Recent efforts have focused on acquiring HSCs by differentiation of pluripotent stem cells.

Fabrication of a fiber-type hepatic tissue by bottom-up method using multilayer spheroids.

Liver regenerative medicine, a therapy using cultured hepatocytes or hepatic tissues, has the potential to replace liver transplantation. However, this therapeutic strategy has challenges to overcome, including in construction of the hepatic tissues. As an approach to fabricating functional 3D hepatic tissues, we focused on hepatocyte spheroids, which have high cell density and maintain high liver-specific functions.

Early repair of necrotic lesion of the femoral head after high-degree posterior rotational osteotomy in young patients-a study evaluated by volume measurement using magnetic resonance imaging.

We investigated the repair of femoral head necrosis with extensive necrotic lesions treated by high-degree posterior rotational osteotomy (HDPRO) in young adults and adolescents (mean age; 30.8 years) using magnetic resonance imaging (MRI). HDPRO was performed on 72 hips from 66 cases, and of those, 60 hips from 60 cases were included in this study for data analysis.

Formation of three-dimensional hepatic tissue by the bottom-up method using spheroids.

Liver regenerative medicine has attracted attention as a possible alternative to organ transplantation. To address the challenge of liver regenerative medicine, the development of a construction method has been proposed for liver tissue in vitro with a high cell density and high functionality for transplantation into patients with severe liver failure. In this study, we fabricated highly functional three-dimensional hepatic tissue by a bottom-up method using spheroids.

Evaluation of a hybrid artificial liver module based on a spheroid culture system of embryonic stem cell-derived hepatic cells.

Hybrid artificial liver (HAL) is an extracorporeal circulation system comprised of a bioreactor containing immobilized functional liver cells. It is expected to not only serve as a temporary liver function support system, but also to accelerate liver regeneration in recovery from hepatic failure. One of the most difficult problems in developing a hybrid artificial liver is obtaining an adequate cell source.

Hepatic differentiation of mouse embryonic stem cells and induced pluripotent stem cells during organoid formation in hollow fibers.

We have focused on pluripotent stem cells as a potential source of a hybrid-type artificial liver (HAL) and tried to develop a method for differentiating the pluripotent stem cells into cells of a hepatic lineage. In this study, we investigated the hepatic differentiation of mouse embryonic stem (ES) cells and induced pluripotent stem (iPS) cells by applying hollow fiber (HF)/organoid culture method, in which cultured cells form a cellular aggregate called an "organoid" in the lumen of the HF. ES and iPS cells were injected into HFs to induce organoid formation, and cells were cultured.

In vitro reconstruction of a three-dimensional mouse hematopoietic microenvironment in the pore of polyurethane foam.

Hematopoietic stem cells exist in specific niches in the bone marrow, and generate either more stem cells or differentiated hematopoietic progeny. In such microenvironments, cell-cell and cell-matrix interactions are as important as soluble factors such as cytokines. To provide a similar environment for in vitro studies, a three-dimensional culture technique is necessary.

Evaluation of instability after transtrochanteric anterior rotational osteotomy for nontraumatic osteonecrosis of the femoral head.

Background: Transtrochanteric anterior rotational osteotomy results in improvement of joint congruity and prevention of progressive collapse and osteoarthritic changes in patients with femoral head osteonecrosis. However, this procedure remains controversial for patients with extensive collapse due to potential osteoarthritis caused by postoperative instability. The purpose of this study was to evaluate hip instability after osteotomy and determine the relation between instability and radiological and clinical outcomes.

Evaluation of a bioreactor with stacked sheet shaped organoids of primary hepatocytes.

Hepatocyte organoids have an in vivo-like cell morphology and maintain cell viability and function in vitro. On the other hand, the oxygen supply to hepatocytes is sometimes limited in the core of organoids that are more than 100 mum in thickness. In this study, we designed and examined a new bioreactor using sheet-shaped organoids (organoid-sheets) in which the thickness was controlled to prevent hepatocyte death in the core of organoid due to limitation of oxygen supply.

Respherical contour with medial collapsed femoral head necrosis after high-degree posterior rotational osteotomy in young patients with extensive necrosis.

Osteonecrosis of the femoral head often occurs in patients under the age of 50 years. In this study, the authors evaluated the effectiveness of high-degree posterior rotation in terms of regaining the spherical contour of severely collapsed necrotic femoral head that was moved medially. They also investigated whether or not subchondral fracture disappeared on the medial femoral head on postoperative anteroposterior radiographs as a result of remodeling after this procedure.

An approach for formation of vascularized liver tissue by endothelial cell-covered hepatocyte spheroid integration.

Tissue vascularization in vitro is necessary for cell transplantation and is a major challenge in tissue engineering. To construct large and regularly vascularized tissue, we focused on the integration of endothelial cell-covered spheroids. Primary rat hepatocytes were cultured on a rotary shaker, and 100-150 mum spheroids were obtained by filtration.

Reconstruction of cartilage tissue using scaffold-free organoid culture technique.

We applied the scaffold-free culture method to chondrocytes and attempted to reconstitute articular cartilage grafts. Primary rat costal chondrocytes were immobilized into hollow fibers by centrifugation at a density of 3 x 10(8) cells/cm(3) to induce the formation of cylindrical-shaped multicellular aggregates (organoids) and cultured for one month. The organoids were evaluated by histological and gene expression analyses.

Hepatic differentiation of mouse embryonic stem cells in a three-dimensional culture system using polyurethane foam.

Embryonic stem (ES) cells are a type of pluripotent stem cell line isolated from the inner cell mass of blastocysts and characterized by an almost unlimited self-renewal capacity and differentiation potential in vitro into multiple cell lineages. Therefore the use of ES cells has recently received much attention as a novel cell source for various hybrid artificial organs. To use ES cells, it is necessary to be able to produce functional matured cells from ES cells in large quantities.

A new culture technique for hepatocyte organoid formation and long-term maintenance of liver-specific functions.

To develop a useful hybrid artificial liver, it is important to use cultured hepatocytes that maintain liver-specific functions for a long time. These requirements were achieved recently by the use of a hepatocyte multicellular aggregate (organoid) with a tissue-like structure. In this study, we developed a three-dimensional culture of hepatocytes that formed an organoid.

[Transtrochanteric rotational osteotomy for the treatment of non-traumatic osteonecrosis of the femoral head].

Non-traumatic osteonecrosis involving the femoral head frequently occurs in young patients especially due to steroids administration or other some reasons. In cases of extensive lesion of the weight-bearing area, collapse is usually progressive. Preservation of the joint in young patients to avoid joint replacement procedures is important and widely accepted.

Posterior rotational osteotomy for nontraumatic osteonecrosis with extensive collapsed lesions in young patients.

Background: In young patients with nontraumatic femoral head osteonecrosis with extensive and collapsed lesions, joint preservation is a goal if total joint arthroplasty is to be avoided. We evaluated the effectiveness of a posterior rotational osteotomy in this patient population.

Methods: We reviewed thirty-five hips in twenty-eight young patients with nontraumatic femoral head osteonecrosis treated by posterior femoral neck rotational osteotomy.