Evaluation of the Microvascular Research Center Training Program for Assessing Microsurgical Skills in Trainee Surgeons

Seiji Komatsu,Kiyoshi Yamada,Shuji Yamashita,Narushi Sugiyama,Eijiro Tokuyama,Kumiko Matsumoto1,Ayumi Takara,Yoshihiro Kimata 대한성형외과학회 2013 Archives of Plastic Surgery Vol.40 No.3

Background We established the Microvascular Research Center Training Program (MRCP)to help trainee surgeons acquire and develop microsurgical skills. Medical students were recruited to undergo the MRCP to assess the effectiveness of the MRCP for trainee surgeons. Methods Twenty-two medical students with no prior microsurgical experience, who completed the course from 2005 to 2012, were included. The MRCP comprises 5 stages of training,each with specific passing requirements. Stages 1 and 2 involve anastomosing silicone tubes and blood vessels of chicken carcasses, respectively, within 20 minutes. Stage 3 involves anastomosing the femoral artery and vein of live rats with a 1-day patency rate of >80%. Stage 4 requires replantation of free superficial inferior epigastric artery flaps in rats with a 7-day success rate of >80%. Stage 5 involves successful completion of one case of rat replantation/transplantation. We calculated the passing rate for each stage and recorded the number of anastomoses required to pass stages 3 and 4. Results The passing rates were 100% (22/22) for stages 1 and 2, 86.4% (19/22) for stage 3, 59.1% (13/22) for stage 4, and 55.0% (11/20) for stage 5. The number of anastomoses performed was 17.2±12.2 in stage 3 and 11.3±8.1 in stage 4. Conclusions Majority of the medical students who undertook the MRCP acquired basic microsurgical skills. Thus, we conclude that the MRCP is an effective microsurgery training program for trainee surgeons.

A Proposal of Wheel/Rail Contact Model for Friction Control

Kosuke Matsumoto,Yoshihiro Suda,Hisanao Komine,Takuji Nakai,Masao Tomeoka,Kunihito Shimizu,Masuhisa Tanimoto,Yasushi Kishimoto,Takashi Fujii 대한기계학회 2005 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.19 No.1S

Controlling the friction between wheel and rail is direct and very effective measures to Improve the curving performances of railway trucks, because the curving performances depend much on friction characteristics Authors have proposed a method, "fllction control", which utilizes friction modifier (KELTRACKTM HPF) with onboard spraying system With the method, not only friction coefficient, but also fuction characteristics can be controlled as expected In this study, MBD simulation is very valuable tool to foresee the effect of the contiol In advance of experiment With real car And the creep characteristics of wheel/rail contact With the friction modifier takes very Important role In the simulation In this paper, authors propose a theoretical model of wheel/rat I contact condition considering the creep characteristics of friction modifier, Which is derived the application of principle tribological theories<br/>

Comparison of Effects of Alendronate and Raloxifene on Lumbar Bone Mineral Density, Bone Turnover, and Lipid Metabolism in Elderly Women with Osteoporosis

Jun Iwamoto,Yoshihiro Sato,Mitsuyoshi Uzawa,Tsuyoshi Takeda,Hideo Matsumoto 연세대학교의과대학 2008 Yonsei medical journal Vol.49 No.1

Purpose: To compare the effects of alendronate and raloxifene on lumbar bone mineral density (BMD), bone turnover, and lipid metabolism in elderly women with osteoporosis. Subjects and Methods: One hundred twenty- two postmenopausal women with osteoporosis (mean age: 69.4 years) were randomly divided into 2 groups of 61 patients: the alendronate group and the raloxifene group. BMD of the lumbar spine, urinary level of cross-linked N-terminal telopeptides of type I collagen (NTX), and serum levels of alkaline phosphatase (ALP), total cholesterol (TC), high and low density lipoprotein cholesterols (LDL-C and HDL-C, respectively), and triglycerides (TG) were measured during the 12-month-treatment period. Results: The trial in 50 patients in the alendronate group and 52 patients in the raloxifene group could be completed. Both alendronate and raloxifene increased lumbar BMD (+8.0% and +2.4% at 12 months, respectively), followed by reductions of urinary NTX level and serum ALP level; however, the effects of alendronate were more pronounced than those of raloxifene. Only raloxifene reduced the serum levels of TC and LDL-C (-3.9% and -7.7% at 12 months, respectively), without any significant effect on the serum HDL-C and TG levels. Conclusion: The present study confirmed the efficacy of alendronate greater than raloxifene in increasing lumbar BMD through its effect on marked reduction of the bone turnover more than by raloxifene, and some beneficial effects of raloxifene on lipid metabolism in elderly women with osteoporosis.

Comparison of the Effects of Alendronate and Alfacalcidol on Hip Bone Mineral Density and Bone Turnover in Japanese Men Having Osteoporosis or Osteopenia with Clinical Risk Factors for Fractures

Jun Iwamoto,Yoshihiro Sato,Mitsuyoshi Uzawa,Tsuyoshi Takeda,Hideo Matsumoto 연세대학교의과대학 2009 Yonsei medical journal Vol.50 No.4

Purpose: The comparative effects of alendronate and alfacalcidol on bone mineral density (BMD) and bone turnover have already been established in postmenopausal women with osteoporosis. An open-labeled prospective study was conducted to compare the treatment effects of alendronate and alfacalcidol on hip BMD and bone turnover in Japanese men with osteoporosis or osteopenia with clinical risk factors for fractures. Materials and Methods: One hundred twelve men with osteoporosis or osteopenia with clinical risk factors for fractures (mean age: 71.4 years) were randomly divided into two groups of 56 patients each: the alendronate (5 mg daily) and alfacalcidol (1 μg daily) groups. The BMD of the total hip, urinary level of cross-linked N-terminal telopeptides of type I collagen (NTX), and serum levels of bone-specific alkaline phosphatase (BSAP) were measured during the 12-month-treatment period. Results: Forty-five patients in the alendronate group and 42 patients in the alfacalcidol group completed the trial. Alendronate increased BMD (+2.3% at 12 months) following reductions in the urinary level of NTX (-46.4% at 3 months) and serum level of BSAP (-34.1% at 12 months), while alfacalcidol sustained BMD (-1.9% at 12 months) as well as the urinary level of NTX (+13.2% at 3 months) and serum level of BSAP (+1.8% at 12 months). Conclusion: The present study confirmed that alendronate has better efficacy than alfacalcidol (active control) in increasing hip BMD and reducing bone turnover in Japanese men with osteoporosis or osteopenia with clinical risk factors for fractures. Purpose: The comparative effects of alendronate and alfacalcidol on bone mineral density (BMD) and bone turnover have already been established in postmenopausal women with osteoporosis. An open-labeled prospective study was conducted to compare the treatment effects of alendronate and alfacalcidol on hip BMD and bone turnover in Japanese men with osteoporosis or osteopenia with clinical risk factors for fractures. Materials and Methods: One hundred twelve men with osteoporosis or osteopenia with clinical risk factors for fractures (mean age: 71.4 years) were randomly divided into two groups of 56 patients each: the alendronate (5 mg daily) and alfacalcidol (1 μg daily) groups. The BMD of the total hip, urinary level of cross-linked N-terminal telopeptides of type I collagen (NTX), and serum levels of bone-specific alkaline phosphatase (BSAP) were measured during the 12-month-treatment period. Results: Forty-five patients in the alendronate group and 42 patients in the alfacalcidol group completed the trial. Alendronate increased BMD (+2.3% at 12 months) following reductions in the urinary level of NTX (-46.4% at 3 months) and serum level of BSAP (-34.1% at 12 months), while alfacalcidol sustained BMD (-1.9% at 12 months) as well as the urinary level of NTX (+13.2% at 3 months) and serum level of BSAP (+1.8% at 12 months). Conclusion: The present study confirmed that alendronate has better efficacy than alfacalcidol (active control) in increasing hip BMD and reducing bone turnover in Japanese men with osteoporosis or osteopenia with clinical risk factors for fractures.

Retraction: Paper “Comparison of the Effects of Alendronate and Alfacalcidol on Hip Bone Mineral Density and Bone Turnover in Japanese Men Having Osteoporosis or Osteopenia with Clinical Risk Factors for Fractures” by Iwamoto J, et al. [Yonsei Med J 20

Jun Iwamoto,Yoshihiro Sato,Mitsuyoshi Uzawa,Tsuyoshi Takeda,Hideo Matsumoto 연세대학교의과대학 2023 Yonsei medical journal Vol.64 No.3

We have decided to retract the paper entitled “Comparison of the Effects of Alendronate and Alfacalcidol on Hip Bone Mineral Density and Bone Turnover in Japanese Men Having Osteoporosis or Osteopenia with Clinical Risk Factors for Fractures” [Yonsei Med J 2009 Aug;50(4):474-481] by Iwamoto J, Sato Y, Uzawa M, Takeda T, Matsumoto H. From information obtained after publication, we have recently become aware of a number of issues related to scientific misconduct.

Which Side-Bending X-ray Position is Better to Evaluate the Preoperative Curve Flexibility in Adolescent Idiopathic Scoliosis Patients, Supine or Prone?

Hirofumi Bekki,Katsumi Harimaya,Yoshihiro Matsumoto,Kenichi Kawaguchi,Mitsumasa Hayashida,Seiji Okada,Toshio Doi,Yasuharu Nakashima 대한척추외과학회 2018 Asian Spine Journal Vol.12 No.4

Study Design: Prospective cohort study. Purpose: The present study aimed to evaluate the difference in the preoperative curve fl exibility between the supine and prone positions in patients with adolescent idiopathic scoliosis (AIS). Overview of Literature: In AIS, a side-bending view is necessary to differentiate a structural curve from a nonstructural curve using the Lenke classifi cation system. However, there are no published studies about which position, supine or prone, is more effective when evaluating preoperative curve fl exibility using side-bending X-ray images in AIS patients. Methods: Radiographs were analyzed for 32 AIS patients (26 females, six males) who underwent posterior correction and fusion of their main thoracic (MT) curves. Cobb angles of MT, proximal thoracic (PT), and thoracolumbar/lumbar (TL/L) curves were measured preoperatively using upright, supine (anteroposterior and side-bending), and prone (posteroanterior and side-bending) X-rays. Results: The average Cobb angles of PT, MT, and TL/L curves on preoperative upright/supine/prone X-rays were 29.1°/26.7°/26.6°, 60.7°/48.5°/48.2°, and 41.0°/32.6°/33.1°, respectively. The average Cobb angles of PT, MT, and TL/L curves on supine/prone sidebending X-rays were 19.2°/20.3°, 36.3°/36.4°, and 13.9°/15.7°, respectively. The fl exibility rates of PT, MT, and TL/L curves in supine/ prone positions were 35.3%/32.5%, 40.6%/40.2%, and 71.7%/68.2%, respectively. Comparing fl exibility rates in the prone position with those in the supine position in each case, the average ratios of PT, MT, and TL/L curves were found to be 1.0, 1.0, and 0.9, respectively. There were no statistically signifi cant differences between supine and prone side-bending X-ray measurements. However, the Lenke classifi cation in six of 32 patients (18.8%) differed between supine and prone positions because the TL/L curve in the supine position was slightly more fl exible than in the prone position. Conclusions: Supine side-bending fi lms may be suitable for the evaluation of preoperative curve fl exibility in AIS, especially for lumbar modifi er C.

Comparison of the Effect of Vitamin K2 and Risedronate on Trabecular Bone in Glucocorticoid-Treated Rats: A Bone Histomorphometry Study

Jun Iwamoto,Hideo Matsumoto,Tsuyoshi Tadeda,Yoshihiro Sato,James K. Yeh 연세대학교의과대학 2009 Yonsei medical journal Vol.50 No.2

Purpose: To compare the effect of vitamin K2 and risedronate on trabecular bone in glucocorticoid (GC)-treated rats. Materials and Methods: Forty-eight Sprague-Dawley female rats, 3 months of age, were randomized by the stratified weight method into 5 groups according to the following treatment schedule: age-matched control, GC administration, and GC administration with concomitant administration of vitamin K2, risedronate, or vitamin K2 + risedronate. GC (methylprednisolone sodium succinate, 5.0 mg/kg) and risedronate (10 μg/kg) were administered subcutaneously three and five times a week, respectively. Vitamin K2 (menatetrenone, 30 mg/kg) was administered orally three times a week. At the end of the 8-week experiment, bone histomorphometric analysis was performed on trabecular bone of the tibial proximal metaphysis. Results: GC administration decreased trabecular bone mass compared with age-matched controls because of decreased bone formation (mineralizing surface, mineral apposition rate, and bone formation rate) and increased bone erosion. Vitamin K2 attenuated GC-induced trabecular bone loss by preventing GC-induced decrease in bone formation (mineralizing surface) and subsequently reducing GC-induced increase in bone erosion. Risedronate prevented GC-induced trabecular bone loss by preventing GC-induced increase in bone erosion although it also suppressed bone formation (mineralizing surface, mineral apposition rate, and bone formation rate). Vitamin K2 mildly attenuated suppression of bone formation (mineralizing surface) and bone erosion caused by risedronate without affecting trabecular bone mass when administered in combination. Conclusion: The present study showed differential effect of vitamin K2 and risedronate on trabecular bone in GC-treated rats. Purpose: To compare the effect of vitamin K2 and risedronate on trabecular bone in glucocorticoid (GC)-treated rats. Materials and Methods: Forty-eight Sprague-Dawley female rats, 3 months of age, were randomized by the stratified weight method into 5 groups according to the following treatment schedule: age-matched control, GC administration, and GC administration with concomitant administration of vitamin K2, risedronate, or vitamin K2 + risedronate. GC (methylprednisolone sodium succinate, 5.0 mg/kg) and risedronate (10 μg/kg) were administered subcutaneously three and five times a week, respectively. Vitamin K2 (menatetrenone, 30 mg/kg) was administered orally three times a week. At the end of the 8-week experiment, bone histomorphometric analysis was performed on trabecular bone of the tibial proximal metaphysis. Results: GC administration decreased trabecular bone mass compared with age-matched controls because of decreased bone formation (mineralizing surface, mineral apposition rate, and bone formation rate) and increased bone erosion. Vitamin K2 attenuated GC-induced trabecular bone loss by preventing GC-induced decrease in bone formation (mineralizing surface) and subsequently reducing GC-induced increase in bone erosion. Risedronate prevented GC-induced trabecular bone loss by preventing GC-induced increase in bone erosion although it also suppressed bone formation (mineralizing surface, mineral apposition rate, and bone formation rate). Vitamin K2 mildly attenuated suppression of bone formation (mineralizing surface) and bone erosion caused by risedronate without affecting trabecular bone mass when administered in combination. Conclusion: The present study showed differential effect of vitamin K2 and risedronate on trabecular bone in GC-treated rats.

Effects of Risedronate on Osteoarthritis of the Knee

Jun Iwamoto,Tsuyoshi Takeda,Yoshihiro Sato,Hideo Matsumoto 연세대학교의과대학 2010 Yonsei medical journal Vol.51 No.2

The purpose of the present study was to discuss the effects of risedronate on osteoarthritis (OA) of the knee by reviewing the existing literature. The literature was searched with PubMed, with respect to prospective, double-blind,randomized placebo-controlled trials (RCTs), using the following search terms: risedronate, knee, and osteoarthritis. Two RCTs met the criteria. A RCT (n = 231) showed that risedronate treatment (15 mg/day) for 1 year improved symptoms. A larger RCT (n = 1,896) showed that risedronate treatment (5 mg/day, 15 mg/day, 35 mg/week, and 50mg/week) for 2 years did not improve signs or symptoms, nor did it alter radiological progression. However, a subanalysis study (n = 477) revealed that patients with marked cartilage loss preserved the structural integrity of subchondral bone by risedronate treatment (15 mg/day and 50 mg/week). Another subanalysis study (n = 1,885)revealed that C-terminal crosslinking telopeptide of type II collagen (CTX-II) decreased with risedronate treatment in a dose-dependent manner, and levels reached after 6 months were associated with radiological progression at 2 years. The results of these RCTs show that risedronate reduces the marker of cartilage degradation (CTX-II), which could contribute to attenuation of radiological progression of OA by preserving the structural integrity of subchondral bone. The review of the literature suggests that higher doses of risedronate (15 mg/day) strongly reduces the marker of cartilage degradation (CTX-II), which could contribute to attenuation of radiological progression of OA by preserving the structural integrity of subchondral bone.

Kinetics and Mechanism for the Scavenging Reaction of the 2,2-Diphenyl-1-picrylhydrazyl Radical by Synthetic Artepillin C Analogues

Kawashima, Tomonori,Manda, Sushma,Uto, Yoshihiro,Ohkubo, Kei,Hori, Hitoshi,Matsumoto, Ken-ichiro,Fukuhara, Kiyoshi,Ikota, Nobuo,Fukuzumi, Shunichi,Ozawa, Toshihiko,Anzai, Kazunori,Nakanishi, Ikuo The Chemical Society of Japan 2012 Bulletin of the Chemical Society of Japan Vol.85 No.8

Influence of Ovariectomy on Bone Turnover and Trabecular Bone Mass in Mature Cynomolgus Monkeys

Jun Iwamoto,Azusa Seki,Masao Matsuura,Yoshihiro Sato,Tsuyoshi Takeda,Hideo Matsumoto,James K. Yeh 연세대학교의과대학 2009 Yonsei medical journal Vol.50 No.3

Purpose: To examine the influence of ovariectomy (OVX) on bone turnover and trabecular bone mass at the 3 clinically important skeletal sites in mature cynomolgus monkeys. Materials and Methods: Six female cynomolgus monkeys, aged 17-21 years, were randomized into 2 groups by the stratified weight: the OVX and sham-operation groups (n = 3 in each group). The experimental period was 16 months. Lumbar bone mineral density (BMD) in vivo and serum and urinary bone turnover markers were longitudinally measured, and peripheral quantitative computed tomographic and bone histomorphometric analyses were performed on trabecular bone of the lumbar vertebra, femoral neck, and distal radius at the end of the experiment. Results: OVX induced in a reduction in lumbar BMD compared with the sham controls and the baseline, as a result of increased serum levels of bonespecific alkaline phosphatase and urinary levels of cross-lined N- and C-terminal telopeptides of type I collagen. Furthermore, OVX induced reductions in trabecular volumetric BMD and trabecular bone mass compared with the sham controls, with increased bone formation rate at the lumbar vertebra, femoral neck, and distal radius. Conclusion: The results indicated that OVX in mature cynomolgus monkeys (17-21 years of age) increased bone turnover and induced trabecular bone loss at the three skeletal sites compared with the sham controls. Thus, mature cynomolgus monkeys could be utilized for preclinical studies to examine the effects of interventions on bone turnover and trabecular bone mass at the 3 clinically important skeletal sites. Purpose: To examine the influence of ovariectomy (OVX) on bone turnover and trabecular bone mass at the 3 clinically important skeletal sites in mature cynomolgus monkeys. Materials and Methods: Six female cynomolgus monkeys, aged 17-21 years, were randomized into 2 groups by the stratified weight: the OVX and sham-operation groups (n = 3 in each group). The experimental period was 16 months. Lumbar bone mineral density (BMD) in vivo and serum and urinary bone turnover markers were longitudinally measured, and peripheral quantitative computed tomographic and bone histomorphometric analyses were performed on trabecular bone of the lumbar vertebra, femoral neck, and distal radius at the end of the experiment. Results: OVX induced in a reduction in lumbar BMD compared with the sham controls and the baseline, as a result of increased serum levels of bonespecific alkaline phosphatase and urinary levels of cross-lined N- and C-terminal telopeptides of type I collagen. Furthermore, OVX induced reductions in trabecular volumetric BMD and trabecular bone mass compared with the sham controls, with increased bone formation rate at the lumbar vertebra, femoral neck, and distal radius. Conclusion: The results indicated that OVX in mature cynomolgus monkeys (17-21 years of age) increased bone turnover and induced trabecular bone loss at the three skeletal sites compared with the sham controls. Thus, mature cynomolgus monkeys could be utilized for preclinical studies to examine the effects of interventions on bone turnover and trabecular bone mass at the 3 clinically important skeletal sites.