Hiroshi Nakamura

Publications (125)403.74 Total impact

• Article: Expression and regulation of a disintegrin and metalloproteinase-8 and -17 in development of rat periradicular lesion.

  Tsuyoshi Tanaka, Nobuaki Ozeki, Rie Kawai, Ichiro Imaizumi, Kazuhiko Nakata, Hiroshi Nakamura
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  ABSTRACT: A disintegrin and metalloproteinases (ADAMs) are a family of transmembrane proteins that share a common domain structure. However, little is known about the possible involvement of ADAM-8 and ADAM-17 in the development of periradicular lesions. Here we demonstrated the expression of ADAM-8 and ADAM-17 in rat periradicular lesions. We induced experimentally periradicular lesions in rats. The animals were killed at 0, 2, 4, 6, and 8 weeks after pulp exposure. The left molars underwent immunofluorescence analysis for both ADAMs and for neutrophil elastase, and right molars were used for reverse transcription-polymerase chain reaction analysis of ADAM-8 and ADAM-17. The areas of these lesions were measured histometrically, and the numbers of all antigen-positive cells in the periapical portion were counted per unit area. The area of the periradicular lesions gradually expanded from 0 to 4 weeks, showing a large increase from week 2 to week 4. Both ADAM-8-positive and ADAM-17-positive cells gradually increased in number from 0 to 4 weeks and then decreased from 4 to 8 weeks. There were more ADAM-17-expressing cells than ADAM-8-expressing ones at all experimental periods except at 4 weeks. The highest expression of ADAM-8 mRNA was observed at 4 weeks, and there were significant differences between 0 and 2 weeks and between 4 and 6 weeks. The expression of ADAM-17 mRNA increased from 0 to 4 weeks and subsequently decreased from 4 to 8 weeks, with a significant difference between 4 and 6 weeks. Our results suggest that ADAM-8 and ADAM-17 may be related to the development of rat periradicular lesions.
  Journal of endodontics 05/2013; 39(5):638-42. · 2.95 Impact Factor
• Article: Sphingosine-1-phosphate modulates expression of vascular endothelial growth factor in human articular chondrocytes: a possible new role in arthritis.

  Kayo Masuko, Minako Murata, Moroe Beppu, Hiroshi Nakamura, Tomohiro Kato, Kazuo Yudoh
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  ABSTRACT: Although sphingosine-1-phosphate (S1P) is suggested to have an important role in arthritis, its function in chondrocytes remains unknown. In contrast, vascular endothelial growth factor (VEGF) has been speculated to contribute to the pathogenesis of osteoarthritis (OA), most likely by regulating angiogenesis. We here investigated the in vitro effect of S1P on VEGF expression in human articular chondrocytes from OA patients. Human articular cartilage samples were obtained from patients with OA under informed consent. Chondrocytes were isolated by an enzymatic procedure, grown in monolayer culture, and then stimulated with S1P in the presence or absence of mitogen-activated protein kinase (MAPK) inhibitors or the Gi protein inhibitor pertussis toxin (PTX). VEGF expression and secretion in culture supernatants were analyzed using real-time polymerase chain reaction and enzyme-linked immunosorbent assay. Although S1P did not enhance basal secretion of matrix metalloproteinase (MMP)-1 and MMP-13, it stimulated VEGF expression in human articular chondrocytes, both at the messenger RNA and protein levels. MAPK inhibitors SB203580 and PD98059 were not effective at suppressing VEGF induction; rather, blocking extracellular signal-regulated kinase (ERK) MAPK enhanced VEGF expression. The Gi protein inhibitor PTX partially attenuated S1P-induced VEGF secretion. Our results suggest that S1P may contribute to the regulation of VEGF expression in human chondrocytes. S1P may therefore play a unique role in the pathophysiology of OA by regulating VEGF expression in chondrocytes.
  International Journal of Rheumatic Diseases 08/2012; 15(4):366-73. · 0.81 Impact Factor
• Article: Layilin, a talin-binding hyaluronan receptor, is expressed in human articular chondrocytes and synoviocytes and is down-regulated by interleukin-1β

  Minako Murata, Kazuo Yudoh, Hiroyuki Shimizu, Moroe Beppu, Hiroshi Nakamura, Tomohiro Kato, Kayo Masuko
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  ABSTRACT: OBJECTIVE: Layilin (LAYN), a 55-kDa transmembrane protein with homology to C-type lectins, has been identified as a receptor of hyaluronan (HA). Interestingly, LAYN does not share any sequence homology with CD44, a primary HA receptor. The primary aim of our study was to examine the expression and potential function of LAYN in human articular chondrocytes and synoviocytes. METHODS: Samples were obtained from patients undergoing joint arthroplasty. Cells were grown in vitro, then stimulated with interleukin (IL)-1β or tumor necrosis factor alpha (TNFα) for 24 h and the expression of LAYN was analyzed. To assess the function of LAYN, we transfected chondrocytes with siRNA against LAYN, treated them with HA and IL-1β, and then analyzed the production of matrix metalloproteinase (MMP)-1 and MMP-13 in the treated chrondrocytes. RESULTS: The results showed that LAYN was constitutively expressed in human articular chondrocytes and synoviocytes and that IL-1β significantly suppressed the expression of LAYN in these cells. HA repressed IL-1β-induced MMP-1 and MMP-13 production in chondrocytes, but this was significantly abrogated in chondrocytes transfected with siRNA against LAYN. CONCLUSIONS: Our results show that human chondrocytes express LAYN, a novel HA receptor, and that LAYN may contribute to the regulation of HA functions in the arthritic condition. Further investigation of the HA receptor may lead to the development of novel therapeutics to regulate HA signaling in inflammatory arthritis.
  Modern Rheumatology 06/2012; · 1.58 Impact Factor
• Article: Effects of medium composition on optical properties and microstructures of non-close-packed colloidal crystalline arrays

  Hiroshi Nakamura, Masahiko Ishii
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  ABSTRACT: The effects of medium composition on the optical properties and microstructures of non-close-packed silica colloidal crystalline arrays have been demonstrated. Water–alcohol mixtures were used as dispersion media for these arrays. Optical properties and microstructures were examined using angle-resolved reflection spectra measurements. The Bragg diffraction peaks of the colloidal crystalline arrays shifted with changing of concentration or hydrocarbon number of alcohol. With an increase in concentration or hydrocarbon number of alcohol, the effective refractive index of the dispersion increased and the interplanar spacing of the colloidal crystalline array decreased. The increase in effective refractive index was caused by an increase in the refractive index of the mixed medium with the change in solvent. The decrease in interplanar spacing of the array was caused by decreased electrostatic repulsions between the silica spheres with decreasing dielectric constant. The current work suggests new possibilities for the control of optical properties and microstructures of colloidal crystalline arrays.
  Colloid and Polymer Science 04/2012; 285(7):833-837. · 2.33 Impact Factor
• Article: Proteomic analysis of bone marrow-adherent cells in rheumatoid arthritis and osteoarthritis.

  Toshikazu Kamada, Manae S Kurokawa, Tomohiro Kato, Kenji Takenouchi, Kenji Takahashi, Takuya Yoshioka, Teisuke Uchida, Hiroyuki Mitsui, Naoya Suematsu, Kazuki Okamoto, Kazuo Yudo, Yasuo Katayama, Hiroshi Nakamura
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  ABSTRACT: To elucidate the pathophysiology of rheumatoid arthritis (RA) as well as osteoarthritis (OA), we analyzed protein profiles of bone marrow-derived adherent cells (BMACs) from patients with these diseases. Proteins, extracted from BMACs from three RA and three OA patients, were comprehensively analyzed by 2-dimensional differential image gel electrophoresis (2D-DIGE). Then a part of the detected proteins, differently expressed between the two diseases, were identified by mass spectrometric analysis. 2D-DIGE analysis detected more than 1600 protein spots in both RA and OA BMACs. Out of these, expression of 340 spots was significantly altered between the diseases (more than 1.5-fold: RA > OA, 26 spots; OA > RA, 314 spots; P < 0.05). Eleven protein spots the intensity of which were significantly altered by more than 2.0-fold were identified, which included vimentin and annexin A5 as increased proteins in RA rather than in OA. As increased proteins in OA compared to RA, alpha chain of collagen VI, a membrane anchor for acetylcholine esterase, heat shock protein 27, caldesmon and cytoskeletal proteins, such as beta actin and alpha tubulin, were identified. We here report different protein profiles of BMACs between RA and OA for the first time. BMACs possessing differently expressed proteins may be involved in the pathophysiology of the two diseases.
  International Journal of Rheumatic Diseases 04/2012; 15(2):169-78. · 0.81 Impact Factor
• Article: Newly developed mineral trioxide aggregate containing polyvinyl alcohol.

  Mitsunori Yamamoto, Harumasa Wanibe, Kazuhiko Nakata, Shozo Tsuruta, Tatsushi Kawai, Hiroshi Nakamura
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  ABSTRACT: The purpose of this study was to examine the apatite-formation ability and the viscosity of a mineral trioxide aggregate (MTA)polyvinyl alcohol (PVA) paste prepared. The MTA-PVA paste immersed in an artificial body fluid generated carbon apatite containing magnesium. The MTA-PVA paste exhibited fluidity and increased compressive strengths. It was considered possible to adjust the apparent viscosity of MTA paste by changing the concentration of the PVA solution. The MTA-PVA paste obtained using a 3-10 wt% PVA solution displayed a structural viscosity. The use of MTA may be elevated by the MTA-PVA paste with syringes in the field of endodontic treatment in order to improve MTA's operability.
  Dental Materials Journal 01/2012; 31(6):1014-20. · 1.14 Impact Factor
• Article: Expression of Angiotensin II Receptor-1 in Human Articular Chondrocytes.

  Yuki Kawakami, Kosuke Matsuo, Minako Murata, Kazuo Yudoh, Hiroshi Nakamura, Hiroyuki Shimizu, Moroe Beppu, Yutaka Inaba, Tomoyuki Saito, Tomohiro Kato, Kayo Masuko
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  ABSTRACT: Background. Besides its involvement in the cardiovascular system, the renin-angiotensin-aldosterone (RAS) system has also been suggested to play an important role in inflammation. To explore the role of this system in cartilage damage in arthritis, we investigated the expression of angiotensin II receptors in chondrocytes. Methods. Articular cartilage was obtained from patients with osteoarthritis, rheumatoid arthritis, and traumatic fractures who were undergoing arthroplasty. Chondrocytes were isolated and cultured in vitro with or without interleukin (IL-1). The expression of angiotensin II receptor types 1 (AT1R) and 2 (AT2R) mRNA by the chondrocytes was analyzed using reverse transcription-polymerase chain reaction (RT-PCR). AT1R expression in cartilage tissue was analyzed using immunohistochemistry. The effect of IL-1 on AT1R/AT2R expression in the chondrocytes was analyzed by quantitative PCR and flow cytometry. Results. Chondrocytes from all patient types expressed AT1R/AT2R mRNA, though considerable variation was found between samples. Immunohistochemical analysis confirmed AT1R expression at the protein level. Stimulation with IL-1 enhanced the expression of AT1R/AT2R mRNA in OA and RA chondrocytes. Conclusions. Human articular chondrocytes, at least partially, express angiotensin II receptors, and IL-1 stimulation induced AT1R/AT2R mRNA expression significantly.
  Arthritis. 01/2012; 2012:648537.
• Article: Increased expression of S100 calcium binding protein A8 in GM-CSF-stimulated neutrophils leads to the increased expressions of IL-8 and IL-16.

  Masayoshi Katano, Kazuki Okamoto, Naoya Suematsu, Manae S Kurokawa, Hiroshi Nakamura, Kayo Masuko, Kazuo Yudoh, Tomohiro Kato
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  ABSTRACT: In our previous proteomic surveillance, we found that at least 11 proteins in neutrophils were increased more than 2.5-fold by the stimulation of GM-CSF. In this paper, focusing on one of the 11 proteins, S100 calcium binding protein A8 (S100A8), we tried to elucidate the effect of S100A8 and the cooperative effect of S100A8 and GM-CSF on production and secretion of cytokines of neutrophils. S100A8 in neutrophil was detected by western blotting, and concentrations of S100A8 in synovial fluid (SF) from patients with rheumatoid arthritis (RA) and osteoarthritis (OA) were measured by ELISA. Cytokine levels in the culture medium of neutrophils incubated with and without S100A8 were measured by an antibody array. IL-8 and IL-16 levels in the culture medium of neutrophils stimulated with S100A8, GM-CSF, and the combination of S100A8 and GM-CSF were measured by ELISA. The mRNA levels of IL-8 and IL-16 in the stimulated neutrophils were analysed by real-time PCR. The western blotting analysis confirmed that S100A8 is up-regulated in neutrophil by the stimulation of GM-CSF. Furthermore, the ELISA analysis confirmed that S100A8 was significantly elevated in SF of patients with RA compared to SF of patients with OA. S100A8 induced mRNA expression and secretion of IL-8 and IL-16. S100A8 further enhanced production of IL-8 by GM-CSF but not that of IL-16. These data suggest that S100A8 may be involved in the exacerbation of RA, and that S100A8 may be a therapeutic target of RA.
  Clinical and experimental rheumatology 09/2011; 29(5):768-75. · 2.15 Impact Factor
• Article: Sarcoidosis with pulmonary hypertension exacerbated by Takayasu-like large vessel vasculitis.

  Aya Ishii, Yoshinobu Hoshii, Tadaaki Nakashima, Seiji Umemoto, Hiroshi Nakamura, Nobuyuki Tanaka, Masunori Matsuzaki, Eiji Ikeda
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  ABSTRACT: A 72-year-old male visited the hospital with a complaint of dyspnea. Under the diagnosis of pulmonary hypertension (PH) due to chronic thrombotic and/or embolic disease, this patient received anti-coagulant therapy. Unfortunately, the respiratory state deteriorated and died 34 days after admission. At autopsy, noncaseating granulomas, which were diagnostic of sarcoidosis, were found in bilateral enlarged hilar lymph nodes, lungs, heart, liver, spleen, testis and epididymis. In pulmonary vasculature, the following three kinds of lesions were observed; (i) sarcoid granulomatous vasculitis at the peripheral arteries and veins, (ii) intimal fibrous lesions ubiquitously found in proximal and peripheral arteries which were thought to be organized thromboemboli, (iii) Takayasu-like large vessel vasculitis with a huge fresh mural thrombus narrowing the lumen of most proximal portion of right pulmonary artery. Autopsy findings indicate that chronic sustained PH state in this patient was attributable to thrombotic and/or thromboembolic disease, and Takayasu-like vasculitis with thrombus played a role in the final deterioration of respiratory state through exacerbation of PH. In sarcoidosis patients, vasculitic lesions which can be formed in both small and large pulmonary arteries must be raised as the differential diagnosis for the initial cause of PH as well as the accelerating factor of PH.
  Pathology International 09/2011; 61(9):546-50. · 1.62 Impact Factor
• Article: Elevation of serum KL-6 levels in 3 patients with rheumatoid arthritis treated with adalimumab.

  Masahito Koiwa, Susumu Goto, Kenji Takenouchi, Kenji Takahasi, Toshikazu Kamada, Hiroshi Nakamura
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  ABSTRACT: We describe 3 cases of rheumatoid arthritis presenting with elevated serum KL-6 levels during treatment with adalimumab, which was discontinued because of suspected onset of complications. However, no complications were observed following discontinuation despite comprehensive assessments, and KL-6 levels subsequently returned to baseline levels. In our institutes, 3 out of 29 cases treated with adalimumab showed elevated KL-6 levels. The baseline levels were 445, 347, and 547 U/ml, while the peak levels were 1010, 546, and 2007 U/ml, respectively. The elevated KL-6 levels seem to have been innocuous; nevertheless, further careful observation is deemed necessary.
  Modern Rheumatology 07/2011; 22(1):147-51. · 1.58 Impact Factor
• Article: The effects of radiofrequency hyperthermia on pain and function in patients with knee osteoarthritis: a preliminary report.

  Kenji Takahashi, Hiromasa Kurosaki, Sanshiro Hashimoto, Kenji Takenouchi, Toshikazu Kamada, Hiroshi Nakamura
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  ABSTRACT: The clinical evidence of the efficacy of hyperthermia on osteoarthritis (OA) has not yet been clearly established. In addition, the application of a modality that can control the temperature inside the joints has not been reported. The purpose of this study was to investigate the effect of percutaneous radiofrequency hyperthermia, which could safely raise the temperature of the body core, in patients with OA knees. Temperature changes inside the knee joint without OA were measured during exposure to radiofrequency. Radiofrequency hyperthermia was performed on 12 OA knees by exposure to 8 MHz and 200 W for 20 min, 3 times, at 1-week intervals. The clinical outcome was evaluated by use of the Lequesne index (LI) and the Japan Orthopaedic Association (JOA) scale. The osteoarthritis research society international (OARSI) responder criteria were also analyzed. Radiofrequency hyperthermia of 8 MHz and 200 W for 20 min increased the temperature inside the joint from 34.4 to 39.4°C. The LI decreased by 3.55 points from baseline during the 3 weeks. The JOA scale improved significantly during the period, reaching 86.25 points at the final examination from baseline of 67.5 points. 67% of patients had a response to the therapy according to OARSI criteria. No side effects were observed. Radiofrequency hyperthermia can safely increase the temperature inside the knee joint. Radiofrequency hyperthermia on OA knees provides a remarkable pain relief effect and can improve the patients' daily life. In the future, clinical studies should be performed with a protocol containing more cases, with appropriate control groups.
  Journal of Orthopaedic Science 05/2011; 16(4):376-81. · 0.84 Impact Factor
• Article: Arthritogenicity of annexin VII revealed by phosphoproteomics of rheumatoid synoviocytes.

  Kosuke Matsuo, Mitsumi Arito, Koji Noyori, Hiroshi Nakamura, Manae S Kurokawa, Kayo Masuko, Kazuki Okamoto, Kouhei Nagai, Naoya Suematsu, Kazuo Yudoh, Moroe Beppu, Tomoyuki Saito, Tomohiro Kato
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  ABSTRACT: To identify novel proteins involved in the pathogenesis of rheumatoid arthritis (RA) and to characterise the identified proteins based on pathogenic and therapeutic aspects. The authors applied differential phosphoproteomic analysis to articular synoviocytes between RA and osteoarthritis (OA) to identify proteins differently phosphorylated between RA and OA. Focusing on annexin VII (Anx7), one of the highly phosphorylated proteins in RA, the authors prepared Anx7-transgenic C57BL/6 (Anx7-Tg-B6) mice to evaluate their susceptibility to collagen-induced arthritis (CIA). In addition, the authors examined the effect of anti-Anx7 antibodies (Abs) on CIA and serum levels of cytokines in wild-type DBA/1J mice, which are known to be susceptible to CIA, and in Anx7-Tg-B6 mice. In vitro, the authors examined the effect of the Anx7 knockdown by small interfering RNA on the secretion of cytokines in rheumatoid synoviocytes and the human synovial sarcoma cell line SW982. The Anx7 transgene altered the CIA-resistant B6 mice to CIA-susceptible ones. The Abs treatment suppressed CIA even in the wild-type DBA/1J mice. The serum levels of cytokines including interleukin 6 (IL-6) and TNFα were not altered by the Abs treatment in vivo. On the other hand, the knockdown of Anx7 by small interfering RNA caused downregulation of IL-8 secretion in vitro. These results indicate that Anx7 participates in the pathogenesis of RA partly through the secretion of IL-8. The study data have demonstrated the pathogenic roles and therapeutic significance of Anx7 in RA for the first time.
  Annals of the rheumatic diseases 05/2011; 70(8):1489-95. · 8.11 Impact Factor
• Article: Tunable angle-independent structural color from a phase-separated porous gel.

  Naomi Kumano, Takahiro Seki, Masahiko Ishii, Hiroshi Nakamura, Yukikazu Takeoka
  Angewandte Chemie International Edition 03/2011; 50(17):4012-5. · 13.45 Impact Factor
• Article: A hybrid two-component system of Tannerella forsythia affects autoaggregation and post-translational modification of surface proteins.

  Daisuke Niwa, Kiyoshi Nishikawa, Hiroshi Nakamura
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  ABSTRACT: Tannerella forsythia is a Gram-negative oral anaerobe closely associated with both periodontal and periapical diseases. The ORF TF0022 of strain ATCC 43037 encodes a hybrid two-component system consisting of an N-terminal histidine kinase and a C-terminal response regulator. Disruption of the TF0022 locus enhanced autoaggregation of the broth-cultured cells. Comparative proteome analyses revealed that two S-layer proteins in the TF0022 mutant exhibited decreased apparent masses by denaturing gel electrophoresis, suggesting a deficiency in post-translational modification. Furthermore, the mutant decreased the production of a glycosyltransferase encoded by TF1061 that is located in a putative glycosylation-related gene cluster. Quantitative real-time PCR revealed reduced transcription of TF1061 and the associated genes in the TF0022 mutant. These results indicate that TF0022 upregulates the expression of the glycosylation-related genes and suggest modulation of the autoaggregation of T. forsythia cells by a possible post-translational modification of cell-surface components.
  FEMS Microbiology Letters 03/2011; 318(2):189-96. · 2.04 Impact Factor
• Article: LIQUID-CRYSTAL COMPOSITES: Multicolor Polymer-Dispersed Liquid Crystal (Adv. Mater. 7/2011).

  Naomi Kumano, Takahiro Seki, Masahiko Ishii, Hiroshi Nakamura, Tomonari Umemura, Yukikazu Takeoka
  Advanced Materials 02/2011; 23(7):883. · 13.88 Impact Factor
• Article: Multicolor polymer-dispersed liquid crystal.

  Naomi Kumano, Takahiro Seki, Masahiko Ishii, Hiroshi Nakamura, Tomonari Umemura, Yukikazu Takeoka
  Advanced Materials 02/2011; 23(7):884-8. · 13.88 Impact Factor
• Article: Recent trends in orthopedic surgery performed in Japan for rheumatoid arthritis.

  Shigeki Momohara, Sakae Tanaka, Hiroshi Nakamura, Junya Mibe, Takuji Iwamoto, Katsunori Ikari, Jinju Nishino, Yuho Kadono, Tetsuro Yasui, Kenji Takahashi, Kenji Takenouchi, Kenzo Hashizume, Ryuichi Nakahara, Ayako Kubota, Takashi Nakamura, Keiichiro Nishida, Toru Suguro
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  ABSTRACT: The aim of this report was to review the use of orthopedic surgeries performed to manage rheumatoid arthritis (RA). Our review of studies published in English indicates that there has been a decrease in RA-associated surgeries in Western countries. Improvements in medical treatment may partly explain the reduction in numbers of orthopedic joint surgeries, which also suggests a worldwide trend toward improved long-term outcomes. However, the results of our multicenter study in Japan indicate that the number of RA-associated operations has not decreased, and that the numbers of operations performed annually have been relatively stable from 1998 to 2008. Although there definitely has been a decline in the numbers of synovectomy surgeries, the numbers of operations on the upper limbs and foot arthroplasties have increased. With the trend toward milder disease because of improved medical treatment, we speculate that RA patients may want and need better function for the activities of daily living. The combination of medical treatment and surgical intervention is thought to improve outcomes in RA patients who will develop joint destruction. Additional studies, including analyses of RA databases containing long-term data on a variety of surgical interventions, are needed.
  Modern Rheumatology 02/2011; 21(4):337-42. · 1.58 Impact Factor
• Article: Selected physical properties of a PEMA-based resin for possible use in a root canal filling material.

  Harumasa Wanibe, Mitsunori Yamamoto, Kazuhiko Nakata, Tatsushi Kawai, Hiroshi Nakamura
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  ABSTRACT: The purpose of this study was to examine the physical properties of PEMA-TA/HX-based resins including 20 to 100% ethanol, for a root canal filling material. The values of the elastic modulus in the samples including ethanol were more than 250 MPa, being higher than the approximately 40 MPa of Gutte-percha (GP). The values of compressive strain in the samples increased in an ethanol concentration-dependent manner. The weight of samples including ethanol decreased gradually. In the adhesiveness test, the values of PEMA-TA/HX-based resins including ethanol were significantly higher than that of GP (p<0.01). Cohesive fractures were observed in Super-Bond SEALER in the samples including ethanol except for 20%. The results suggest that the new PEMA-TA/HX-based resin cone in combination with resin-based sealer might facilitate "monoblock obturation". The new PEMA-TA/HX-based resin cone developed in the present study may be effective root canal filling material for vertical root fractures.
  Dental Materials Journal 01/2011; 30(1):52-7. · 1.14 Impact Factor
• Article: Collagenolytic activity in sonic extracts of Tannerella forsythia.

  Norio Kawase, Jun-ichi Kishi, Hiroshi Nakamura, Taro Hayakawa
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  ABSTRACT: The purpose of the present study was to characterize the collagenolytic activity in a sonicated extract of Tannerella forsythia and to investigate the activation of proMMMP-2 and -9 by the T. forsythia extract. The T. forsythia extract was incubated with type I collagen. The cleaved products were then analyzed by SDS-PAGE using the method of Laemmli. We studied the effects of cysteine, DTT, CaCl(2), and various proteinase inhibitors on collagenolytic activity. A HT1080 cell culture supernatant containing proMMP-2 and -9 was incubated with the T. forsythia extract and analyzed for the activation of proMMP-2 and -9 by gelatin zymography. The T. forsythia extract degraded type I collagen. Cysteine increased the collagenolytic activity of the extract, and 5mM CaCl(2) was required for this activity. The collagenolytic activity of T. forsythia was inhibited by N-ethylmaleimide, iodoacetamide, iodoacetic acid, EDTA, and leupeptin, but not by PMSF, E-64, TLCK, or TPCK. When proMMP-2 and -9 were incubated with the T. forsythia extract, gelatinases with the relative molecular masses of MMP-2 and -9 were produced. The present study suggests that T. forsythia extract is able to degrade type I collagen and activate proMMP-2 and -9.
  Archives of oral biology 08/2010; 55(8):545-9. · 1.65 Impact Factor
• Article: Angle-independent structural color in colloidal amorphous arrays.

  Mohammad Harun-Ur-Rashid, Abu Bin Imran, Takahiro Seki, Masahiko Ishii, Hiroshi Nakamura, Yukikazu Takeoka
  ChemPhysChem 02/2010; 11(3):579-83. · 3.41 Impact Factor