Papers by Author: Akitaka Nonomura

Paper TitlePage

Authors: Takafumi Yoshikawa, Y. Ueda, Takahito Ohmura, Yasunori Sen, Jin Iida, M. Koizumi, K. Kawate, Yoshinori Takakura, Akitaka Nonomura
Authors: Noriko Okumura, Takafumi Yoshikawa, Akitaka Nonomura, Yoshinori Takakura
Abstract: HA has a high affinity for bone as well as various tissues. In the present study, we investigated an affinity for abdominal organs. Coralline hydroxyapatite ceramic (HA, cubic structure 4x4x4mm, Interpore 500) was used in this experiment. We made two incisions in the lower back of a 5-week-old male nude mouse, and implanted HA blocks. One was placed around the liver at the right side and another one was placed around the kidney at the left side. The organ fibrous capsule was not removed. At 6 weeks after implantation, mice were sacrificed under overanesthesia and HA blocks were retrieved and prepared for histological analysis. In the HE stain of HA blocks around liver, liver tissue is invaded into the HA pore areas. Hepatocyte proliferation in trabecular pattern was seen in contact with the surfaces of many HA pores. Within some pores, hepatic lobular pattern, Glisson sheath or central vein could be detected. In the HA around kidney, renal tissue was observed in many pores. The pore areas of HA were fullfilled with grumerulus and urinary tube tissues. In contact with the surfaces of some HA blocks, the tissue invasion of pancreas and spleen tissue were recognized. These results indicate that porous HA has a high affinity for the celiac organs, and has a stimulatory effect on celiac organ regeneration. Especially, concerning the regeneration of kidney, it has not been reported yet, so this report is very interesting. HA is also very useful as a scaffold of the organ regeneration.
Authors: N. Satoh, Takafumi Yoshikawa, A. Muneyasu, Jin Iida, Akitaka Nonomura, Yoshinori Takakura
Authors: Noriko Okumura, Takafumi Yoshikawa, Jin Iida, Akitaka Nonomura, Yoshinori Takakura
Abstract: The effect of genistein, a soybean isoflavone, on new bone formation by bone marrow cells from mature humans was examined. After informed consent was obtained from a 55-year-old woman with osteoporosis and lumbar spondylosis deformans,bone marrow cells were collected from her ilium, cultured in the standard medium of MEM containing fetal calf serum and then cultured with or without the addition of genistein to the bone-forming medium containing dexamethasone etc.. In humans, when genistein was added to the bone-forming medium, genistein (10-7 M and 10-8 M)caused a significant increase in the levels of alkaline phosphatase avtivity and DNA content compared with cells not cultured in genistein. In conclusion,genistein was found to promote bone formation at lower concentrations,and thus may be useful as a bone formation-promoting factor.
Authors: Noriko Okumura, Takafumi Yoshikawa, Jin Iida, Akitaka Nonomura, Yoshinori Takakura
Authors: Takafumi Yoshikawa, Y. Ueda, M. Koizumi, Jin Iida, Kazuhide Miyazaki, Hideki Shigematsu, N. Satoh, Akitaka Nonomura, Yoshinori Takakura
Abstract: Posterolumbar fusion, which involves placing a bone graft in the posterolateral portion of the spine, has been applied to patients with lumbar instability due to structural defects or regressive degeneration. However, harvesting cancellous bone from the ilium is associated with severe postoperative pain, and patients experience more pain at the harvest site than at the graft site, thus resulting in poor patient satisfaction. If a tissue engineering approach was used to produce autogenous bone ex vivo with culture techniques, spinal fusion could be performed without damaging normal tissues. In all patients, 10 to 20 mL of bone marrow fluid was collected from the ilium and cultured in MEM containing autologous serum or fetal bovine serum and an antibiotic. After two weeks in primary culture, the marrow mesenchymal cells were seeded onto porous beta-TCP block, and tissue engineered bone were fabricated as we reported previously. Decompressive laminectomy and posterolateral lumbar fusion with use of the tissue engineered bone thus obtained were then done. In all patients, the implanted artificial bone survived and bone regeneration was detected radiographically, and the clinical symptoms were improved. Short term follow-up has shown that the bone implants were effective in all of the patients. There were no adverse reactions related to implantation. The use of this tissue engineered bone makes it possible to perform osteogenetic treatment without harvesting autogenous bone, thus avoiding pain and pelvic deformity at the site of bone collection and reducing the burden on the patient.
Authors: Takafumi Yoshikawa, Y. Ueda, Takahito Ohmura, Yasunori Sen, Jin Iida, M. Koizumi, Kazuhide Miyazaki, Yoshinori Takakura, Akitaka Nonomura
Abstract: Subjects were graft patients with pseudoarthrosis (average age, 60.3 years; range, 17-85 years). Pseudoarthrosis affected the thoracolumbar spine, the femur, the clavicle, the humerus and the metatarsal. From the ilium (tibia in one patient), 10-20 ml of bone marrow fluid was collected, and then, it was immediately transferred to the culture room and incubated in a flask containing MEM with 15% autologous or fetal bovine serum, etc.. After 2 weeks in primary culture, cells were released by trypsin treatment and were subsequently incubated with porous beta-TCP in order to prepare tissue-engineered artificial bone, according to the previously reported modified culturing technique. Tissue-engineered artificial bone was grafted around the non-union site of each affected long bone, while tissue-engineered artificial bone was grafted via the pedicle of each affected vertebral body. In all patients, favorable bone formation was seen at three months after surgery. In the patients with pseudoarthrosis of the spine, CT and MRI confirmed favorable vertebral body formation. In the patients with pseudoarthrosis of a long bone, the artificial bone was remodeled and favorable bone union was confirmed. In 2 patients in whom bone biopsy was performed during pin removal, bone regeneration was confirmed histologically. With present type of tissue-engineered artificial bone, an artificial material with a high bone regeneration capacity can be prepared by aspiration, which is minimally invasive, and thus when compared to iliac bone grafts, it is possible to radically reduce postoperative pain without damage of autologous bone.
Showing 1 to 7 of 7 Paper Titles