Biomedical subjects

Satoru Ozeki

Publications and source records attributed to Satoru Ozeki.

11 recordsLinked to original sources

PubMed2006

Transcription promoter activity of the human S100A7 gene in oral squamous cell carcinoma cell lines.

The S100A7 (psoriasin) gene has been shown to be markedly over-expressed in squamous cell carcinomas (SCCs) as well as in psoriasis. We herein examined the S100A7 gene promoter activity in human oral SCC cell lines to identify the putative SCC-specific regulatory regions for the S100A7 transcription. Functional deletion assays of 5'-flanking region demonstrated that the segments, (-1513 to -988), (-1954 to -1513) and (-3040 to -2578), play important roles in the transcription activity in the oral SCCs. The internal deletion of the short segments, (-1248 to -1110), (-1109 to -988) and (-1248 to -988), decreased this activity. These segments cloned upstream of the heterologous promoter increased the promoter activity in oral SCC cell line. Electrophoretic mobility shift assays, using the sequence segmental probes, (-1248 to -1110) and (-1109 to -988), showed different DNA-protein complex patterns depending on the types of used cell lines. One of the complexes was only observed in the oral SCCs. These data suggested that the segment from -1513 to -988 contains up-regulatory elements for the transcription activity of the S100A7 gene in oral SCCs.

Calcium-Binding Proteins↗

PubMed2006

Devastating massive knee defect reconstruction using the cornucopian chimera flap from the subscapular axis: two case reports.

Two cases of successful reconstruction of massive defects around the knee with multiple-island combined flaps based on the subscapular axis are reported. Both defects resulted from aggressive debridement for acute osteomyelitis after open fixation of high-energy fractures around the knee. In Case 1, a four-island combined flap consisting of the scapular flap, the lattissimus dorsi muscle flap, the serratus anterior muscle flap, and the scapular osseous flap, based on the same subscapular axis, was used. Partial bone transport using the Ilizarov apparatus was added as reinforcement of arthrodesis. In Case 2, a five-island combined flap, consisting of the scapular, parascapular flap, the lattissimus dorsi muscle flap, the serratus anterior fascial flap, and the scapular osseous flap, was used. Consequent ankylosis of the knee joint afforded the patient painless full weight bearing without secondary arthrodesis. Multiple-island combined flaps based on the subscapular axis can provide three-dimensional reconstruction of destructive knee defects.

Adult↗

PubMed2006

Ankle ligament tensile forces at the end points of passive circumferential rotating motion of the ankle and subtalar joint complex.

BACKGROUND: Ankle ligament injuries and instability are commonly observed. Knowledge of the relationship between the foot position and tensile forces of the ankle ligaments could be useful for treatment of ankle ligament disorders. The aim of this study was to measure the tensile forces of the ankle ligaments at the end points of passive circumferential rotating motion of the ankle and subtalar joint complex in various foot positions. METHODS: Ligament tensile forces of the anterior talofibular (ATF), calcaneofibular (CF), posterior talofibular (PTF), and tibiocalcaneal (TC) ligaments were measured simultaneously in eight cadaver specimens, with a force probe in each ligament in a custom-made ankle ligament testing device. Weights of 0.5 kg and 1 kg were applied to the foot through a loading arm to provide axial compression and a bending moment to the foot and ankle. The position of the loading arm was changed circumferentially in 10-degree increments. RESULTS: Maximal tensile force in the ATF ligament was observed in supination with plantarflexion (108 +/- 62.8 N at 0.5 kg and 130 +/- 39.1 N at 1 kg). The maximal tensile force in the CF ligament was observed in pronation with plantarflexion (68 +/- 48.6 N at 0.5 kg and 135 +/- 92.9 N at 1 kg). The maximal tensile force in the PTF ligament was observed in dorsiflexion (131 +/- 80.1 N at 0.5 kg and 109 +/- 36.3 N at 1 kg). The maximal tensile force of the TC ligament was observed in pronation with plantarflexion (49.0 +/- 80.1 N at 0.5 kg and 67.4 +/- 69.6 N at 1 kg). Relatively high magnitudes of tensile force were observed in the ankle ligaments, and the peak forces were related to the anatomic position of individual ligaments. CONCLUSIONS: The ATF ligament has an important role in the supination position in plantarflexion, CF and TC ligaments also are important for pronation in plantarflexion, and the PTF is an important stabilizer in dorsiflexion. This study provides baseline information for further research related to ligament instability and reconstruction operations.

Aged↗

PubMed2005

Oral squamous cell carcinoma cells induce osteoclast differentiation by suppression of osteoprotegerin expression in osteoblasts.

The invasion of oral squamous cell carcinoma (SCC) cells into the mandibular bone is a common clinical problem. It has been reported that BHY cells, a human oral SCC cell line, are capable of invading mandibular bone of nude mice. These results led us to examine possible mechanisms of osteoclastogenesis induced by BHY cells using in vitro culture systems. When BHY cells were cocultured with mouse bone marrow cells (BMCs), only few osteoclasts were formed, even though BHY cells express the receptor activator of NF-kappaB ligand (RANKL). However, adding BHY cells to a coculture of mouse primary osteoblasts (POBs) and BMCs markedly induced osteoclastogenesis in the absence of osteotropic factors. Furthermore, another oral SCC cell line, HSC-2, which does not express RANKL, also induced osteoclastogenesis in our cocultures. These effects were significantly, but not completely, inhibited by adding osteoprotegerin (OPG). In addition, we also found that TNFalpha released from these cells partially contributes to osteoclastogenesis via a RANKL-independent mechanism. Adding BHY or HSC-2 cells suppressed mouse OPG mRNA expression and protein production by POBs in cocultures of POBs and human oral SCC cells. This finding is consistent with the result that BHY cells and HSC-2 cells did not enhance osteoclastogenesis in cocultures of BMCs and POBs from OPG-deficient mice. Immunohistochemical analysis showed a reduction of OPG expression in osteolytic lesions as compared to normal lesions from oral SCC patients. Therefore, oral SCC-induced suppression of OPG expression in POBs appears critical for osteoclastogenesis, rather than expression of RANKL in SCC cells.

Animals↗

PubMed2005

Effect of SCCA1 and SCCA2 on the suppression of TNF-alpha-induced cell death by impeding the release of mitochondrial cytochrome c in an oral squamous cell carcinoma cell line.

This study examined the effect of squamous cell carcinoma antigen 1 (SCCA1) and SCCA2 on TNF-alpha-induced cell death in human oral squamous cell carcinoma cell lines. The viability of MISK81-5 and sMISK cells treated with TNF-alpha dose-dependently decreased. The sMISK cells which stably overexpressed SCCA1 and SCCA2 cDNA showed a greater resistance against the cell death induced by TNF-alpha than the controls. Immunocytochemical staining for cytochrome c showed a punctate pattern in the cytoplasm of the TNF-alpha-untreated cells. After treatment with TNF-alpha, the punctate staining pattern was preserved in the transfectants, while this pattern disappeared in the controls. In the transfectants, the release of cytochrome c from the mitochondria to cytosol after TNF-alpha treatment was lower than in the controls. A decreased level of active caspase-9 was also observed in the transfectants. These results suggest that both SCCA1 and SCCA2 play a role in the prevention of TNF-alpha-induced cell death in vitro, by inhibiting the release of mitochondrial cytochrome c to some degree.

Antigens, Neoplasm↗

PubMed2005

Development and reliability of a standard rating system for outcome measurement of foot and ankle disorders I: development of standard rating system.

BACKGROUND: The aim of this study was to report the five scales comprising the rating system that the Japanese Society for Surgery of the Foot (JSSF) devised (JSSF standard rating system) and the newly offered interpretations and criteria for determinations of each assessment item. METHODS: We produced the new scales for the JSSF standard system by modifying the clinical rating systems established by the American Orthopaedic Foot and Ankle Society (AOFAS scales) and the Japanese Orthopaedic Association's foot rating scale (JOA scale). We also provided interpretations of each assessment item and the criteria of determinations in the new standard system. RESULTS: We improved the ambiguous expressions and content in the conventional standard rating systems so they would be easily understood by Japanese people. The result was five scales in total. Four were designed for use specifically for ankle-hindfoot, midfoot, hallux metatarsophalangeal-interphalangeal, and lesser metatarsophalangeal-ineterphalangeal sites; and the fifth was for the foot and ankle with rheumatoid arthritis. Furthermore, we described interpretations and criteria for determinations with regard to evaluation items in each scale. CONCLUSIONS: Conventionally, the AOFAS scales or the JOA scale have been separately applied depending on the sites or disorders concerned, but it was often difficult to decide on scores during practical evaluations because of differing expressions in different languages and also because of ambiguity in the interpretation of each evaluation item and in scoring standards as well. JSSF improved these scales and added definite interpretations of evaluation items as well as criteria for the rating (to be reported here in part I). Because these steps were expected to improve the reliability of outcomes assessed by each scale, we examined the reliability in scores of the newly developed scales, which are reported in part II (in this issue).

Ankle↗

PubMed2005

Development and reliability of a standard rating system for outcome measurement of foot and ankle disorders II: interclinician and intraclinician reliability and validity of the newly established standard rating scales and Japanese Orthopaedic Association rating scale.

BACKGROUND: This study evaluated the validity and inter- and intraclinician reliability of (1) the Japanese Society of Surgery of the Foot (JSSF) standard rating system for four sites [ankle-hindfoot (AH), midfoot (MF), hallux (HL), and lesser toe (LT)] and the rheumatoid arthritis (RA) foot and ankle scale and (2) the Japanese Orthopaedic Association's foot rating scale (JOA scale). METHODS: Clinicians from the same institute independently evaluated participating patients from their institute by two evaluations at a 1- to 4-week interval. Statistical evaluation was as follows. (1) The intraclass correlation coefficient (ICC) was calculated from data collected from at least two examinations of each patient by at least two evaluating clinicians (Data A). (2) Total scores for the two evaluations were determined from the distribution of differences in data between the two evaluations (Data B); each item was evaluated by determining Cohen's coefficient of agreement. (3) The relation between patient satisfaction and total score was investigated only for patients who underwent surgery (Data C). Spearman's rank correlation coefficient was obtained. RESULTS: Participants were 65 clinicians and 610 patients, including those with disorders of the AH (313), MF (47), HL (153), and LT (50) and those with RA (47). From Data A, the ICC was high for AH and HL by JSSF scales and for AH, MF, and LT by the JOA scale. From Data B, the coefficient showed high validity for both scales for AH, with almost no difference between the two scales; the validity for HL was higher with the JOA scale than with the JSSF scale. From Data C, correlations were significant between patient satisfaction and outcome for AH and HL by the JSSF scales and for AH, HL, and LT by the JOA scale. CONCLUSIONS: The validity of both scales was high. Clinical evaluation of the therapeutic results using these scales would be highly reliable.

Ankle↗

PubMed2003

Central acinic cell carcinoma of the mandible. Case report.

Central acinic cell carcinoma (of the mandible) is rare, and, to our knowledge, only seven cases of this disease have been reported in the literature. A case in a 67-year-old Japanese woman is presented. Clinical examination revealed a 10.0x6.0mm mass located on the buccal aspect of the gingiva of the second molar in the left mandible. Radiographic examination revealed a radiolucency from the second to the third molar of the left mandible. Computed tomography disclosed destruction of the lingual cortical bone of the third molar region. The preliminary diagnosis was of odontogenic tumour. The patient was admitted, and removal of the tumour and of the involved teeth were carried out. Histological examination disclosed the diagnosis of acinic cell carcinoma. Subsequently, the tumour area was widely excised from the second premolar region to the coronoid process, and radical neck dissection was performed. A lymph node metastasis was found in the submandibular region. No recurrence or metastasis was observed during the 34-month follow-up.

Aged↗

PubMed2003

The correlation of histologic features with a panoramic radiography pattern and a computed tomography pattern of bone destruction in carcinoma of the mandibular gingiva.

OBJECTIVE: We sought to clarify the correlation among a computed tomography (CT) or a panoramic radiography (PR) pattern of bone destruction, a histologic pattern of bone destruction, and a mode of invasion in carcinoma of the mandibular gingiva. STUDY DESIGN: CT images, panoramic radiographs, and decalcified, hematoxylin-eosin-stained preparations of the excised mandibular bone of 62 patients with carcinoma of the mandibular gingiva were retrospectively evaluated. Each computed tomograph, panoramic radiograph, and the histologic pattern of bone destruction was classified as 1 of 5 types: erosive, erosive and partly mixed, mixed, mixed and partly invasive, or invasive. The mode of invasion of the tumor was also assessed with a hematoxylin-eosin-stained preparation of the initial biopsy specimen. The relationships among the CT pattern, the PR pattern, the histologic pattern of bone destruction, and the mode of invasion of the tumor were statistically analyzed by using the Spearman rank correlation test. RESULTS: The CT pattern (P =.005) and the PR pattern (P =.003) were significantly correlated with the histologic pattern with respect to the bone destruction. The CT pattern (P =.996), the PR pattern (P =.997), and the histologic pattern (P =.521) of bone destruction were not correlated with the mode of invasion seen in the biopsy specimen. CONCLUSION: The CT pattern and the PR pattern of bone destruction reflect the histologic pattern of bone destruction caused by carcinoma of the mandibular gingiva but are not associated with the mode of invasion of the tumor.

Adult↗

PubMed2002

Primary neck management among patients with cancer of the oral cavity without clinical nodal metastases: A decision and sensitivity analysis.

BACKGROUND: A standardized neck management strategy for oral cancer patients without clinical nodal metastases remains to be established. Consequently, a decision and sensitivity analysis of two neck management protocols, involving either prophylactic neck dissection or careful observation, was conducted using the Oral Cancer Registry of Kyushu, Japan. METHODS: We calculated probabilities of subclinical nodal metastases and 5-year survival using the registry data. A two-way sensitive analysis was conducted using the probabilities and parameters of the complete nodal metastasis resection rate (x) and a utility rating that describes the health state induced by dissection (y) compared with the neck condition in a careful-observation group. RESULTS: We solved the threshold curve for y and x for the expected utility between the two groups. The results showed that prophylactic neck dissection must guarantee a complete resection of subclinical nodal metastases with no disadvantage to health state to be evaluated as equally satisfactory as careful observation. CONCLUSIONS: Careful observation involving standardized systematic preoperative and postoperative screening of the neck seems preferable to prophylactic neck dissection for oral cancer patients without subclinical nodal metastases.

Carcinoma, Squamous Cell↗

PubMed2002

Simultaneous strain measurement with determination of a zero strain reference for the medial and lateral ligaments of the ankle.

The strain changes of the central part of the anterior talofibular ligament (ATFL), the posterior talofibular ligament (PTFL), the calcaneofibular ligament (CFL), and the tibiocalcaneal ligament (TCL) were measured simultaneously for a full range of ankle motion. Twelve fresh frozen amputated ankles were used. To measure the strain changes of the ligaments, a Galium-Indium-filled silastic strain transducer was implanted in the center of each ligament. The zero strain reference was determined immediately after the measurement of strain changes in five of the 12 ankles by tensile testing of each bone-ligament-bone preparation. The maximum strain change of the ATFL, the PTFL, the CFL and the TFL were 7.9%, 5.9%, 5.3% and 5.2%, respectively. The ATFL was elongated in plantar flexion and shortened in dorsiflexion. The PTFL and the CFL were shortened in plantar flexion and elongated in dorsiflexion. The TCL was the longest around the neutral position and became shorter in planter flexion and dorsiflexion. The results showed that the ATFL was taut in plantar flexion over 16.2 degrees, the PTFL and the CFL were taut in dorsiflexion over 18 degrees and 17.8 degrees respectively, and the TCL was taut between 9.5 degrees of dorsiflexion and 9.5 degrees of plantar flexion. The length change pattern was different among the ankle ligaments, although there was only a slight difference between that of the PTFL and the CFL. This study provides fundamental data useful in studying ankle ligament reconstruction.

Adolescent↗