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.

Retraction: Paper “Efficacy of Oral Etidronate for Skeletal Diseases in Japan” by Iwamoto J, et al. [Yonsei Med J 2005 Jun;46(3):313-320]

Jun Iwamoto,Tsuyoshi Takeda,Yoshihiro Sato 연세대학교의과대학 2023 Yonsei medical journal Vol.64 No.5

We have decided to retract the paper entitled “Efficacy of Oral Etidronate for Skeletal Diseases in Japan” [Yonsei Med J 2005 Jun;46(3):313-320.] by Iwamoto J, Takeda T, Sato Y. From information obtained after publication, we have recently become aware of a number of issues related to scientific misconduct.

광 디스크기술을 사용한 소형 우주 광통신 모듈의 연구개발

Iwamoto, Kyohei 한국광학기기산업협회 2019 光學世界 Vol.175 No.-

Prognostic factors for maxillary sinus mucosal thickening following Le Fort I osteotomy: a retrospective analysis

Iwamoto, Masashi,Watanabe, Miki,Yamamoto, Masae,Narita, Masato,Kamio, Takashi,Takaki, Takashi,Shibahara, Takahiko,Katakura, Akira Korean Association of Maxillofacial Plastic and Re 2019 Maxillofacial Plastic Reconstructive Surgery Vol.41 No.-

Background: Le Fort I osteotomy is one of the surgical procedures now routinely and safely performed. It is possible to move the maxilla in three dimensions, but it is necessary to separate the bones around the maxillary sinus. Therefore, with surgery, maxillary sinus mucosal thickening occurs. By knowing the changes in the sinus mucosa after surgery and the factors affecting it, it is possible to better predict the outcomes of surgery and contribute to safer surgery. In this study, thickening of maxillary sinus mucosa before and after surgery in Le Fort I osteotomy was evaluated using multidetector-row computed tomography (MDCT) images, and the changes in mucosal thickening and the related factors were examined. Methods: Using MDCT images, the maxillary sinus mucosa of 125 patients who had undergone Le Fort I osteotomy was retrospectively evaluated before surgery, 1 month after surgery, and 1 year after surgery. On the MDCT images, the maxillary sinus was judged as mucosal thickening and classified into three grades according to the proportion occupying the maxillary sinus. In the evaluation of factors related to mucosal thickening, the following eight factors were examined: sex, age, diagnosis, operating time, amount of postoperative bleeding, with/without bone graft, with/without multisegmental osteotomy, and with/without macrolide therapy after surgery. Results: The mean age at the time of surgery was 25.6 ± 8 years. Of all 125 patients, 66 had bilateral thickening, 19 had unilateral thickening, and 40 had no thickening. Factors that were significantly related to mucosal thickening were the operative time for the maxilla, bone grafts, and macrolide therapy after surgery. Conclusions: Operative time for the maxilla, bone grafts, and macrolide therapy after surgery were found to be related to mucosal thickening. In addition, MDCT scanning 1 month after surgery was considered to be appropriate for evaluation of maxillary sinus mucosal thickening.

Molecular Orientation of Individual Lu@C₈₂ Molecules Demonstrated by Scanning Tunneling Microscopy

Iwamoto, Masachika,Ogawa, Daisuke,Yasutake, Yuhsuke,Azuma, Yasuo,Umemoto, Hisashi,Ohashi, Kazunori,Izumi, Noriko,Shinohara, Hisanori,Majima, Yutaka American Chemical Society 2010 The Journal of Physical Chemistry Part C Vol.114 No.35

<P>We identified the orientation of individual Lu@C<SUB>82</SUB> molecules on alkanethiol self-assembled monolayers (SAMs) by scanning tunneling microscopy (STM) at a molecular resolution. STM images of Lu@C<SUB>82</SUB> on alkanethiol SAMs at 65 K showed a striped structure corresponding to the molecular orbitals of the Lu@C<SUB>82</SUB> molecule, suggesting that thermal rotation of Lu@C<SUB>82</SUB> on alkanethiol SAMs is prevented at 65 K. By comparing these molecular-resolution STM images with Kohn−Sham molecular orbitals of Lu@C<SUB>82</SUB> calculated by density functional theory (DFT), we identified the molecular orientation of Lu@C<SUB>82</SUB>. Spatial mapping of the differential conductance on individual Lu@C<SUB>82</SUB> molecules revealed that the local conductivity within a molecule became large around the Lu atom at a negative sample bias voltage. From spatial mapping of the differential conductance measurements, we also evaluated the HOMO−LUMO gap of Lu@C<SUB>82</SUB> to be 0.47 eV. From the results of the spatial mapping of the differential conductance and DFT calculations, the locally high conductivity around the Lu atom was attributed to the HOMO-2 level orbital concentrated on the Lu atom and its six nearest C atoms at 0.055 eV below the HOMO level. We demonstrated changes in the molecular orientation of Lu@C<SUB>82</SUB> by applying a high electric field (about 1 × 10<SUP>7</SUP> V/cm) with a large tunneling current (1.5 nA).</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jpccck/2010/jpccck.2010.114.issue-35/jp1023394/production/images/medium/jp-2010-023394_0007.gif'></P>

Effect of Asp193 on Proton Affinity of the Schiff Base in pharaonis phoborhodopsin

Iwamoto, Masayuki,Furutani, Yuji,Sudo, Yuki,Shimono, Kazumi,Kandori, Hideki,Kamo, Naoki Korean Society of Photoscience 2002 Journal of Photosciences Vol.9 No.2

Spectroscopic titration of D 193N and D 193E mutants of pharaonis phoborhodopsin (ppR) were performed to evaluate the pK$_{a}$ of the Schiff base Asp 193 corresponds to Glu204 of bacteriorhodopsin (bR). The pK$_{a}$ of the Schiff base (SBH$^{+}$) of D193N was 10.1~10.0 (at XH$^{+}$) and 11.4~11.6 (at X) depending on the protonation state of a certain residue (designated by X) and independent on CI$^{[-10]}$ , while those of the wild-type and D193E were> 12. pK$_{a}$ of XH$^{+}$ were; 11.8~11.2 at the state of SB, 10.5 at SBH$^{+}$ state in the presence of CI$^{[-10]}$ , and 9.6 at SBH$^{+}$ without CI$^{[-10]}$ These imply the presence of a long-range interaction in the extracellular channel.r channel.

Conformations of Ring Polystyrenes in Semidilute Solutions and in Linear Polymer Matrices Studied by SANS

Iwamoto, Takuro,Doi, Yuya,Kinoshita, Keita,Takano, Atsushi,Takahashi, Yoshiaki,Kim, Eunhye,Kim, Tae-Hwan,Takata, Shin-ichi,Nagao, Michihiro,Matsushita, Yushu American Chemical Society 2018 Macromolecules Vol.51 No.17

<P>Conformations of highly purified ring polystyrene, R-70, with the molar mass of 70 kg/mol, in a good solvent and in linear polymer homologue matrices were examined by small-angle neutron scattering (SANS) measurements. The radii of gyration <I>R</I><SUB>g</SUB> of R-70 were estimated by the Guinier’s approximation from the SANS profiles obtained, and the polymer volume fraction Φ dependence of <I>R</I><SUB>g</SUB><SUP>2</SUP> was discussed. In deuterated toluene as a good solvent, R-70 exhibits the <I>R</I><SUB>g</SUB><SUP>2</SUP> ∼ Φ<SUP>-0.29±0.01</SUP> dependence at high Φ above the overlap volume fraction, Φ<SUB>0</SUB>* (i.e., 1 < Φ/Φ<SUB>0</SUB>* < 20). This exponent −0.29 shows stronger Φ dependence than that for semidilute solutions of linear polymers, −0.25, predicted from the scaling theory, suggesting that the ring expands more sensitively than linear chains when Φ decreases in semidilute regime. In contrast, the Φ dependence of <I>R</I><SUB>g</SUB><SUP>2</SUP> of R-70 is evidently weaker than that of the recent simulation for ring polymer solutions (<I>R</I><SUB>g</SUB><SUP>2</SUP> ∼ Φ<SUP>−0.59</SUP>) by Reigh et al. This difference is thought to originate from the difference in the ring chain length; i.e., the simulation treated much longer rings than the ring adopted in this study. Therefore, it is expected that the exponent −0.29 for the ring polymer solutions obtained in this study is not a limiting value but is a transit one toward higher Φ/Φ<SUB>0</SUB>* region. The size of R-70 is also increased when the ring was diluted with linear polystyrenes. However, the degree of expansion of the rings in linear polymer matrices is considerably lower than that in toluene solutions. Moreover, the molar masses of the linear chains added hardly effect the expansion behavior of the rings. In fact, the dimension of rings gets closer to that of the Gaussian rings as a larger amount of linear chains is added.</P> [FIG OMISSION]</BR>

Effect of deflected inflow on flows in a strongly-curved 90 degree elbow

Iwamoto, Yukiharu,Kusuzaki, Ryo,Sogo, Motosuke,Yasuda, Kazunori,Yamano, Hidemasa,Tanaka, Masaaki Korean Society for Fluid machinery 2017 International journal of fluid machinery and syste Vol.10 No.1

Wall pressure measurements and flow visualization were conducted for a 90 degree elbow with an axis curvature radius the same as its inner diameter (125 mm). Reynolds numbers 320,000 and 500,000, based on the inner diameter and bulk velocity, were examined. A deflected inflow, having an almost constant velocity slope and a faster velocity at the inside, was introduced. Ensemble averaged pressure distributions showed that no difference of normalized pressure could be found in both the Reynolds number cases. Power spectral density functions of pressures exhibited that the fluctuation having the Strouhal number (based on the inner diameter and bulk velocity) of 0.6 existed in the downstream region of the elbow, which was 0.1 larger than that of the uniform inflow case [1]. Results of numerical calculations qualitatively coincided with the experimental ones.

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.

Study of interfacial polarization phenomena in organic films by MDC, SHG and surface potential measurement

Mitsumasa Iwamoto,Takaaki Manaka,Kei Yoshiz 한국물리학회 2005 Current Applied Physics Vol.5 No.4

Carrier injection, carrier separation, and carrier transport in the films are key processes in organic devices. Therefore, the understanding of interfacial electrostatic phenomena is of crucial importance. From the view point of dielectric physics, we have been studying the surface polarization phenomena. Using Maxwell displacement current (MDC) measurement, optical second harmonic generation (SHG) measurement, and Kelvin-probe surface potential measurement, surface polarization phenomena at the interfaces have been elucidated experimentally and theoretically. This paper describes how the surface polarization phenomena can be clarified by these measurements. Finally, our experiment on evaporated Alq3 film is shown.