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Dive into the research topics where Tominaga Shimizu is active.

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Featured researches published by Tominaga Shimizu.


Journal of Bone and Mineral Research | 2001

Colocalization of Noggin and Bone Morphogenetic Protein‐4 During Fracture Healing

Yasuo Yoshimura; Shintaro Nomura; Satoshi Kawasaki; Takahiro Tsutsumimoto; Tominaga Shimizu; Kunio Takaoka

The regulation of callus formation during fracture repair involves the coordinate expression of growth factors and their receptors. This article describes the temporal and spatial expression of noggin gene, an antagonist to bone morphogenetic protein (BMP), during the fracture repair process. Noggin expression was examined by means of Northern blotting and in situ hybridization and compared with the expression pattern of BMP‐4 in a model of fracture repair in adult mice. Expression levels of noggin messenger RNA (mRNA) were enhanced in the early phase of fracture callus formation. The localization of the noggin mRNA was similar to that of BMP‐4 mRNA. Distinct noggin mRNA signals were located predominantly in cells lining the periosteum and the cortical endosteum near the fracture site at 2 days after fracture. At 5, 10, and 21 days after fracture, noggin mRNA was detected in the chondrocytes and osteoblasts in the newly formed callus. The pattern of localization was indistinguishable from that of BMP‐4. These results suggest that the noggin/BMP‐4 balance could be an important factor in the regulation of callus formation during fracture healing.


Bone | 1998

Sequential expression of bone morphogenetic protein, tumor necrosis factor, and their receptors in bone-forming reaction after mouse femoral marrow ablation

Tominaga Shimizu; R Mehdi; Yasuo Yoshimura; Hideki Yoshikawa; Shintaro Nomura; Kohei Miyazono; Kunio Takaoka

Tumor necrosis factor-alpha (TNF-alpha) is considered a promoter of bone resorption and a suppressor of osteogenesis, whereas bone morphogenetic protein (BMP) is a promoter of bone formation. In the present study, the osteogenic potential of the medullary cavity after bone marrow ablation was evaluated in association with the pattern of BMP, bone morphogenetic protein receptor (BMPR), TNF-alpha, and tumor necrosis factor receptor (TNFR) expression. Immunostaining, in situ hybridization, and TRAP staining were performed following marrow ablation. By day 4, BMP-4 mRNA was detected by in situ hybridization in growing undifferentiated cells and, on day 7, the osteoblastic cells that covered abundant woven bone also showed evidence of BMP-4 expression. BMPR-IA and BMPR-II were immunolocalized from days 4 to 10 after ablation, and became negative on days 21 and 28. At 10 days postablation, osteoclasts were revealed by TRAP staining. TNF-alpha expression disappeared transiently after ablation and then reappeared on day 7, predominantly in osteoblastic cells. On days 7, 10, and 14, immunostaining for TNFR-I was observed in osteoblasts lining the woven bone and later disappeared. No evidence of TNFR-II staining was observed on osteoblastic cells throughout the reaction. From day 14, newly formed bone decreased in quantity and was replaced by hematopoietic cells and, by day 28, the bone marrow had regenerated to its original state. This study suggests that TNF-alpha is produced and secreted by the osteoblast and acts on these cells in an autocrine manner to suppress osteoblastic function. TNF-alpha may also play a role in the recruitment of osteoclasts because TRAP-positive osteoclasts appeared after TNF-alpha expression.


Bone | 1999

Advantages of concurrent use of anabolic and antiresorptive agents over single use of these agents in increasing trabecular bone volume, connectivity, and biomechanical competence of rat vertebrae

Shinsuke Kobayashi; Tominaga Shimizu; R Mehdi; Masashi Nawata; Seiichi Kojima; Takahiro Tsutsumimoto; Richard Iorio; Kunio Takaoka

The purpose of this study was to evaluate the usefulness of a combination regimen of anabolic and antiresorptive agents in increasing skeletal quantity and quality in comparison to a single-drug regimen with these agents. We examined histomorphometrically and biomechanically the effects of separate and combined administration of intermittent parathyroid hormone (PTH) and estrogen or bisphosphonate on both axial and appendicular skeletons of male Wistar rats, which were 4 months old and weighed approximately 300 g at the beginning of the treatment. The animals were untreated or injected with vehicle, recombinant human PTH(1-84) (PTH; 100 microg/kg daily), 17beta-estradiol (E2, 500 microg/kg every other day), incadronate disodium (YM175, 80 microg/kg every other day), combined PTH and E2 (PTH + E2), or a combination of PTH and YM175 (PTH + YM175). After 1 month of treatment, the three groups in which PTH was administered (PTH, PTH + E2, and PTH + YM175) had significantly higher trabecular bone volume and connectivity in the proximal tibial metaphyses (PTMs) compared with the untreated and vehicle-treated groups, whereas only combination groups (PTH + E2 and PTH + YM175) showed significant increases in these indices in the lumbar vertebrae. This site-related discrepancy was attributed to the fact that PTH significantly elevated bone resorption not in the PTMs but in the vertebrae. This increased bone resorption in the vertebrae was suppressed by the addition of an antiresorptive agent. As a result, trabecular bone mass, connectivity, and mechanical strength of the vertebrae were significantly increased from control levels only in the concurrent treatment groups (PTH + E2 and PTH + YM175). The superior skeletal effects of PTH cotherapy over PTH monotherapy were not seen with regard to bone mass, but with increased connectivity and mechanical strength. The concurrent use of PTH and an antiresorptive agent has been shown to be superior to the single use of PTH for enhancing these properties of rat vertebrae, which encourages future research, especially in larger animals.


Journal of Clinical Neuroscience | 2005

Meningioma arising in Werner syndrome confirmed by mutation analysis.

Yukio Nakamura; Tominaga Shimizu; Youji Ohigashi; Nobuo Itou; Yuichi Ishikawa

OBJECTIVE AND IMPORTANCE Meningioma arising in Werner syndrome has been described previously, but never in association with a mutation analysis. We present the first reported case of meningioma in a patient with Werner syndrome and a confirmed major mutation. In addition, we review 27 previously reported patients with meningioma associated with Werner syndrome. CLINICAL PRESENTATION We report a 56-year-old Japanese woman with Werner syndrome and a meningioma. She presented with pain and redness of the right eye and a headache. Cranial CT revealed a tumor the in right frontal and temporal lobes. Pathological examination after surgical removal confirmed meningioma. She displayed typical features of Werner syndrome including juvenile cataract, short stature and low weight, a bird-like face, a hoarse voice, and dry, atrophic, pigmented skin. INVESTIGATION To confirm the clinical diagnosis, a mutation analysis based on the mutant allele-specific amplification (MASA) method was performed. CONCLUSION Mutation analysis of peripheral blood leukocyte DNA showed amplification of the mutation 4/4. There were 22 patients with Werner syndrome and meningioma reported from Japan and 5 from outside Japan. There was only one malignant meningioma. Meningiomas in Werner syndrome have a higher frequency in males and occur at a younger age than those of the general population.


Clinical Orthopaedics and Related Research | 2004

Low-voltage electrochemotherapy with low-dose methotrexate enhances survival in mice with osteosarcoma.

Kenichi Isobe; Tominaga Shimizu; Toshio Nikaido; Kunio Takaoka

Methotrexate plays a key role in adjuvant chemotherapy for treatment of osteosarcoma, but is used at a high dose because it can pass through a cell membrane only with difficulty. Therefore, if the drug delivery of methotrexate to the tumor could be enhanced, antitumor effect and survival would improve. We examined whether enhancement of the antitumor effect of electrochemotherapy was feasible by using low-dose methotrexate in mice with osteosarcoma. The tumor-bearing mice were divided into four groups: no treatment, methotrexate treatment alone, electroporation alone, and methotrexate treatment followed by electroporation. In single-treatment series, the size of the tumors in mice treated with electrochemotherapy decreased substantially 6 days after treatment, whereas continuous growth was observed in the other groups. In the series of treatments repeated three times at 6-day intervals, the original tumors in the electrochemotherapy group decreased consistently and the tumors disappeared in four of seven animals within 16 days. In the other groups, the tumors continued to grow and all host animals died within 58 days. These results show the usefulness of electroporation to enhance the effects of low-dose methotrexate and the potential benefits of electrochemotherapy for the treatment of human osteosarcoma.


Journal of Hand Surgery (European Volume) | 2002

Callus resection for brachial plexus compression following stress-induced first rib fracture.

Hiroshi Seki; Satoru Saitoh; Yukihiko Hata; Narumichi Murakami; Tominaga Shimizu; Kunio Takaoka

A 27-year-old man presented with a lower trunk brachial plexus injury due to excessive callus formation following a stress-induced first rib fracture. The callus, but not the first rib, was resected through a supraclavicular approach. His symptoms resolved in 2 months, and no recurrence was seen at 2 years follow-up.


Foot & Ankle International | 2003

Three-dimensional starch model for simulation of corrective osteotomy for a complex bone deformity: a case report.

Tominaga Shimizu; Fumio Fujioka; Hiroki Gomyo; Kenichi Isobe; Kunio Takaoka

The complex valgus deformity of the right ankle of a 24-year-old Maffucci syndrome man was corrected by three-dimensional osteotomy followed by limb lengthening. Before surgical correction of the deformity, we used computed tomography data to make a life-size three-dimensional plastic model of the deformed ankle for an accurate understanding of the anatomical deformity. We then used this model to perform a simulated osteotomy. The real osteotomy was performed immediately afterwards and valgus and recurvatum deformities were corrected accurately. We recommend simulated surgery using a three-dimensional plastic model which will improve the pre-operative planning technique and the accuracy of the end results.


Journal of Orthopaedic Science | 2009

Serum soluble interleukin-2 receptor levels in patients with malignant lymphoma of bone

Tsutomu Akahane; Tominaga Shimizu; Kenichi Isobe; Yasuo Yoshimura; Hiroyuki Kato

BackgroundThe reliability of selected serum markers and radiological features for distinguishing malignant lymphoma of the bone from other osteolytic bone lesions was examined in an effort to improve the differential diagnosis.MethodsA total of 23 patients with histologically verified malignant lymphoma of the bone, 57 patients with other osteolytic malignancies (35 males, 22 females; mean age 62.8 years, range 13–89 years), and 13 patients with benign bone lesions that resemble malignant tumor radiographically (6 men, 7 women; mean age 48.1 years, range 20–73 years) were retrospectively reviewed. We evaluated the serum levels of soluble interleukin-2 receptor (sIL-2R), lactate dehydrogenase, and C-reactive protein in addition to radiographic examination and gallium-67 scanning.ResultsAlthough every clinical feature examined was found to show significant differences between lymphoma and the other two groups, the feature most highly suggestive of malignant lymphoma is a high serum sIL-2R level (sensitivity 0.95, specificity 0.70, accuracy 0.81).ConclusionsThe serum sIL-2R level can be a valuable marker for diagnosing malignant lymphoma of the bone.


Acta Orthopaedica | 2005

Serum total acid phosphatase for monitoring the clinical course of giant cell tumors of bone—26 patients with 5 local recurrences

Tsutomu Akahane; Kenichi Isobe; Tominaga Shimizu

Background Giant cell tumor of bone (GCT) is a bone-destroying tumor that sometimes recurs locally after treatment. A recent study showed increased levels of serum total acid phosphatase (TACP). Methods We assessed TACP in the serum of 26 patients with primary GCT, and in 5 of them who developed a local recurrence. Results We found a correlation between TACP level in serum and tumor size. TACP levels that were elevated preoperatively in patients with GCT became normalized after surgery, but increased in 3 of the 5 patients with local recurrence. Interpretation TACP could be used as a tumor marker for monitoring response to treatment of GCT.


Foot & Ankle International | 2005

Recurrence potential of diffuse-type giant cell tumor in the foot : Radiologic and pathologic features

Tominaga Shimizu; Takeshi Uehara; Tsutomu Akahane; Kenichi Isobe; Hideki Arai

Background: Aggressive musculoskeletal tumors in the foot, such as diffuse-type giant cell tumors or extra-abdominal desmoid tumors, are difficult to treat because the foot does not have enough soft tissue to allow wide tumor resection. We reviewed the clinical behavior of diffuse-type giant cell tumor in the foot and evaluated the recurrence potential of these tumors from radiologic and pathologic perspectives. Methods: Six patients with a mean age of 37.6 years were included in this study. Radiologic studies, including sonography, computed tomography (CT), magnetic resonance imaging (MRI), and bone and gallium citrate scintigraphy, were obtained followed by surgical treatment and histologic evaluation of the tumor. Results: Recurrence occurred in three patients. Although CT and MRI findings were similar in the recurrent and nonrecurrent tumors, marked differences were found between the two by scintigraphy; positive radiotracer uptake to the affected foot with gallium citrate scintigraphy was noted only in recurrent tumors, although positive accumulation was seen in all patients with bone scintigraphy. Histologically, the necrotic area and mitotic activity were more apparent in recurrent than in the nonrecurrent tumors, and tumor cell dyscohesion was noted in the former, (the intercellular space was increased). Conclusions: Repeated recurrence with tumor invasion into tarsal bone resulted in breakage of the tarsal arch that supports the bodys weight. Amputation would be necessary for patients in whom the disease had progressed to obtain local cure and relief of pain. In the present study, we found two features of the recurrence potential of diffuse-type giant cell tumors: sparse cell to cell contact on pathologic examination and positive accumulation in the tumor on gallium citrate scintigraphy. We concluded that giant cell tumors with these two features have a strong potential for local recurrence, and thus require intensive followup.

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