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Featured researches published by Masahito Hatori.


Journal of Orthopaedic Science | 2005

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

Hisateru Niki; Haruhito Aoki; Suguru Inokuchi; Satoru Ozeki; Mitsuo Kinoshita; Hideji Kura; Yasuhito Tanaka; Masahiko Noguchi; Shigeharu Nomura; Masahito Hatori; Shinobu Tatsunami

BackgroundThe 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.MethodsWe 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.ResultsWe 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.ConclusionsConventionally, 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).


Journal of Orthopaedic Science | 2005

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

Hisateru Niki; Haruhito Aoki; Suguru Inokuchi; Satoru Ozeki; Mitsuo Kinoshita; Hideji Kura; Yasuhito Tanaka; Masahiko Noguchi; Shigeharu Nomura; Masahito Hatori; Shinobu Tatsunami

BackgroundThis 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).MethodsClinicians 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.ResultsParticipants 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.ConclusionsThe validity of both scales was high. Clinical evaluation of the therapeutic results using these scales would be highly reliable.


Clinical Science | 2004

Sex steroid receptors in rheumatoid arthritis.

Masato Ishizuka; Masahito Hatori; Takashi Suzuki; Yasuhiro Miki; Andrew D. Darnel; Chika Tazawa; Takashi Sawai; Miwa Uzuki; Yasuhisa Tanaka; Shoichi Kokubun; Hironobu Sasano

Rheumatoid arthritis (RA) is a disease characterized primarily by chronic inflammatory synovitis and is well-known to be associated with significant sex differences in its prevalence and clinical features. Sex steroids have been proposed to be involved in the pathogenesis of RA, but details pertaining to the expression of sex steroid receptors in RA synovial tissue have yet to be fully characterized. In the present study, we examined oestrogen receptor (ER) alpha, ERbeta, progesterone receptor (PR) and androgen receptor (AR) mRNA expression using real-time reverse transcriptase-PCR (RT-PCR) in eight female RA synovial tissues and six female synovial tissues without inflammation, and determined immunolocalization of ERalpha, ERbeta, PR-A, PR-B and AR using immunohistochemistry in synovial tissues obtained from 22 RA patients. Real-time RT-PCR analysis demonstrated the expression of ER, PR and AR mRNAs in both RA and non-inflamed synovial tissues. Relative abundance of ER mRNAs was significantly higher in RA synovial tissue than non-inflamed synovial tissue (P<0.05). In addition, the relative ERalpha/ERbeta mRNA expression ratio was significantly lower in RA than non-inflamed synovial tissue (RA, 2.34 +/- 1.60; and non-inflamed, 20.7 +/- 19.1; P<0.05). There were no significant differences in relative abundance of PR mRNA. Relative abundance of AR mRNA was significantly lower in RA (P<0.05). Immunoreactivity for ERalpha, ERbeta, PR-B and AR was detected in the lining cells, inflammatory cells and fibroblasts in all the patients examined. The labelling indices for ERbeta and PR-B were more abundant in both lining cells (ERbeta, 54.2 +/- 12.2%; PR-B, 73.6 +/- 18.9%) and inflammatory cells (ERbeta, 74.6 +/- 16.2%; PR-B, 75.9 +/- 16.1%) than in fibroblasts (ERbeta, 36.5 +/- 15.6%; PR-B, 49.4 +/- 18.0%). Labelling indices for ERalpha and AR were significantly higher in lining cells (ERalpha, 14.4 +/- 8.6%; AR, 31.2 +/- 11.3%) and fibroblasts (ERalpha, 12.1 +/- 7.5%; AR, 20.1 +/- 9.6%) than those in inflammatory cells (ERalpha, 5.7 +/- 3.3%; AR, 9.2 +/- 4.4%). There were significant differences (P<0.05) in the labelling indices for ERalpha, ERbeta and PR-B between men and women under 50 years of age in fibroblasts of RA synovial tissues. These results indicate that sex steroid receptors are present in RA and non-inflamed synovial tissues, including inflammatory cells in RA, and suggest that sex steroids may play important roles in the regulation of inflammation of RA synovial tissue.


Skeletal Radiology | 1999

Peritumoral edema in osteoid osteoma on magnetic resonance imaging

Shigeru Ehara; Daniel I. Rosenthal; Jun Aoki; Kunihiko Fukuda; Hideharu Sugimoto; Hirokazu Mizutani; Kyoji Okada; Masahito Hatori; Masataka Abe

Abstract Objective.To determine whether there is a relationship between the peritumoral edema caused by osteoid osteoma seen on magnetic resonance (MR) imaging and the patient’s age, duration of symptoms, or location of the lesion. Design and patients. All histologically proven osteoid osteomas seen in our institutions during a 5-year period in patients with known age, gender, duration of symptoms, and available radiological and MR imaging examinations were included in this study. The extent of the edema in the bone marrow and extraosseous soft tissue around the nidus of osteoid osteoma on T2-weighted MR imaging were graded from 1 (nonexistent) to 4 (extensive) by two masked observers. The relationships between the patient’s age, duration of symptoms, and location of lesions were evaluated by Pearson’s correlation coefficient and analysis of variance. Results.Twenty-seven cases met the inclusion criteria. The observer agreement on grading was good. Patients of 15 years of age or younger had significantly higher grades than patients older than 15 years. There was a moderate negative linear correlation between the patient’s age and peritumoral edema. No significant relationship was identified between edema and the duration of symptoms or the location of lesions. Conclusion. Osteoid osteomas in younger patients tend to be associated with more extensive peritumoral edema.


Archives of Orthopaedic and Trauma Surgery | 2001

Twenty-six-years' survival with multiple bone metastasis of malignant pheochromocytoma

Shuichi Yoshida; Masahito Hatori; Takao Noshiro; Noriko Kimura; Shoichi Kokubun

Abstract The prognosis of metastatic pheochromocytoma is poor in general. There have been few instances of long-term survival reported. We report a case of a 44-year-old woman who has survived for 26 years after bone metastasis. She was diagnosed as having pheochromocytoma arising in the left adrenal medulla in 1974. Metastasis of pheochromocytoma in the first and third lumbar vertebrae and the right ilium was observed at the same time. The primary lesion was removed, and posterior lumbar spinal fusion was performed for immobilization. The metastatic lesion in the ilium was left untouched. After 26 years, she is well despite a recurrence of the tumors in the skull and a new metastasis in the left abdomen.


Annals of Surgical Oncology | 2004

Osteosarcomas after the age of 50: a clinicopathologic study of 64 cases--an experience in northern Japan.

Kyoji Okada; Tadashi Hasegawa; Jun Nishida; Akira Ogose; Takahiro Tajino; Toshihisa Osanai; Michiro Yanagisawa; Masahito Hatori

Background: The clinicopathologic profile and prognostic factors of osteosarcomas after the age of 50 years have been obscure.Methods: Clinicopathologic features were analyzed in 645 patients with osteosarcoma who were registered at the Tohoku Musculoskeletal Tumor Society and National Cancer Center in Tokyo between 1972 and 2002.Results: Sixty-four patients (9.9%; 34 men and 30 women) were more than 50 years old. The most common location was the distal femur (n = 13), followed by the pelvis (n = 10), proximal femur (n = 9), and proximal fibula (n = 6). Seven (11%) patients had lung metastasis at initial presentation. On radiographs, an osteolytic appearance without periosteal reactions was a common and characteristic feature. Forty-eight tumors (75%) were classified as conventional osteosarcomas. Fourteen cases (22%) were secondary; postradiation osteosarcoma was most common in these patients, but there was no Paget’s sarcoma. At the initial presentation, misdiagnoses without biopsy were made in 15 (23%) of the 64 cases. Preoperative chemotherapy was given to 22 patients, but the effect was poor in 18 cases (82%). Fifty-four patients underwent surgery, whereas the other 10 patients were treated without surgery because of systemic or inoperable local conditions. The overall survival rate at 5 years was 55.5%. Multivariate analysis showed initial pulmonary metastasis, axial tumor location, and larger tumors as significant prognostic factors.Conclusions: In northern Japan, most patients with osteosarcoma after the age of 50 had primary osteosarcoma. Careful radiological examination and biopsy are mandatory for correct diagnosis. Current systemic chemotherapy is not effective for this age group. Alternative treatment strategies should be considered.


Histopathology | 2009

Histogenesis-specific expression of fibroblast activation protein and dipeptidylpeptidase-IV in human bone and soft tissue tumours.

Osamu Dohi; Haruo Ohtani; Masahito Hatori; Elichi Sato; Masami Hosaka; Hiroshi Nagura; Eiji Itoi; Shoichi Kokubun

Aims:  Fibroblast activation protein (FAP)/seprase and dipeptidylpeptidase‐IV (DPP‐IV)/CD26 are serine integral membrane proteases. They are involved in tissue remodelling, cancer invasion and metastases, mechanisms that are controversial. The aim was to identify cell types that express FAP and DPP‐IV in human bone and soft tissue tumours, and to determine whether there are any correlations between the expression of FAP and DPP‐IV and the malignant potential of tumours.


Cancer Science | 2008

Sex steroid receptors expression and hormone‐induced cell proliferation in human osteosarcoma

Osamu Dohi; Masahito Hatori; Takashi Suzuki; Katsuhiko Ono; Masami Hosaka; Jun-ichi Akahira; Yasuhiro Miki; Shuji Nagasaki; Eiji Itoi; Hironobu Sasano

Sex steroid receptors including estrogen receptors (ER), progesterone receptors (PR), and androgen receptors (AR) have been sporadically reported in human osteosarcoma or its cell lines. Therefore, sex steroids have been considered to play some roles in human osteosarcoma, but no systematic and detailed studies regarding the correlation between the status of these receptors in sarcoma cells and clinicopathological parameters have been reported. We examined the existence of ER, PR and AR in 28 cases of osteosarcoma using immunohistochemistry. We then characterized the potential influence of sex steroids on cell proliferation of osteosarcoma cells using MG‐63 human osteosarcoma cell line, which expressed all of these receptors. ER‐β and PR were detected in the great majority of the cases (23 and 24 cases, respectively) but ER‐α and aromatase were not detected in all the cases, and AR was detected only in eight cases. There was a significant positive correlation between ER‐β and Ki‐67 (MIB1) labeling indexes. The absence of aromatase in tumors also suggests the relative importance of concentrations of circulating sex steroids. Proliferation of MG‐63 cells was significantly stimulated by estradiol, progesterone, and 5α‐dihydrotestosterone (DHT), and was significantly suppressed by the addition of fulvestrant (ICI), mifepristone (RU), and hydroxiflutamide, blockers for ER, PR and AR, respectively. Sex steroids, particularly estrogen and progesterone, are considered to play important roles in the regulation of cell proliferation in human osteosarcoma. In addition, these data suggest the potential for a novel endocrine therapy in osteosarcoma using clinically available inhibitors of progesterone and estrogen actions. (Cancer Sci 2008; 99: 518–523)


Molecular and Cellular Endocrinology | 2012

Sex steroid synthesis in human skin in situ: The roles of aromatase and steroidogenic acute regulatory protein in the homeostasis of human skin

Takayoshi Inoue; Yasuhiro Miki; Keiko Abe; Masahito Hatori; Masami Hosaka; Yoshiyuki Kariya; Shingo Kakuo; Tsutomu Fujimura; Akira Hachiya; Seijiro Honma; Setsuya Aiba; Hironobu Sasano

Sex steroids have been known to play important roles in the homeostasis of human skin, but little is known about their biosyntheses in that tissue. In this study, we characterized the correlation between the concentrations of sex steroids and the expression levels of the factors involved in their synthesis or metabolism in human skin. The expression levels of aromatase (ARO) and steroidogenic acute regulatory protein (StAR) were positively correlated with estrogens and testosterone concentrations, respectively. We demonstrated that estrogen synthesis was markedly decreased by ARO inhibitor and that skins with higher ARO expression had thicker elastic fibers than those with lower ARO expression. While pregnenolone and testosterone concentrations were increased by cholesterol administration to epidermal keratinocytes. Scalp skin with higher StAR expression was cleared to have significantly fewer hair follicles than that with lower expression. Our results suggest that the status of ARO and StAR contribute to estrogen synthesis in situ, especially for the regulation of elastic fiber formation, and to testosterone synthesis, which may be associated with hair growth, respectively.


Upsala Journal of Medical Sciences | 2005

Skeletal Muscle Metastasis Secondary to Cancer - A Report of Seven Cases

Yoichi Koike; Masahito Hatori; Shoichi Kokubun

Cancer metastasis to the skeletal muscle is very rare. In this report, we describe 7 cases (6 males, 1 female, age 55-76, mean 66 y.o.) with unusual presentation of cancer metastasis to the skeletal muscle, illustrating the principal clinical, radiographic and histologic features. The primary tumors were lung cancer in 4 cases (3 adenocarcinomas, 1 squamous cell carcinoma) and renal cell carcinoma, esophageal carcinoma, hepatocellular carcinoma in each one. The metastatic sites were the adductors, iliopsoas, rectus femoris, biceps bracii, triceps bracii, deltoid, and paravertebral muscle in each one. The unusual sites of metastases were visualized by CT and/or MRI and confirmed by needle or trocar biopsy. Five patients died in 2 to 24 months with the average of 8 months after initial examination.

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Takashi Yokota

Kyoto Prefectural University of Medicine

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Shigeru Ehara

Iwate Medical University

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