Clinical importance of regeneration or
reconstruction medicine for hard tissues in aging societies.
Manabu Ito
Dept. of Orthopaedic Surgery, Hokkaido University Graduate School of Medicine.
Japan is now moving to a super-aging society with
the highest speed in the world. Population statistics show that more than 40%
of the population in Japan will exceed 65 years of age by the middle
of this century. In order to maintain the quality of life of the elderly,
regeneration or reconstruction medicine of hard tissue is becoming of highest
clinical importance. Through my clinical experience treating senile patients
with osteoporotic spinal fractures and spinal
deformities, I would like to introduce the current status of surgical
treatment for spinal fractures in osteoporotic
collapsing spine and to discuss the future directions of treatment of human
hard tissues.
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Effects of Carbonic Anhydrase
Inhibitor acetazolamide (AZ) on osteoclasts
and bone texture
Chihiro Shinohara1), Fumiaki Kawano1)
and Kikuji Yamashita2)
1)Comprehensive Dentistry1), Institute of Health Biosciences, The
University of Tokushima Graduate School
2)Oral and Maxillofacial Anatomy, Institute of Health Biosciences, The
University of Tokushima Graduate School
Osteoclast-targeting pharmaceutical products have
been developed for the treatment of abnormal bone metabolism. We investigated
the effects of carbonic anhydrase inhibitor acetazolamide (AZ) on osteoclasts
to design a new drug. Bone resorption activity and
the number of osteoclasts decreased by AZ in a doze
dependent manner, showing morphological apoptotic characteristics in bone
marrow culture. The area of trabecular bone was
increased and the density of osteoclasts was
decreased in the AZ-treated rats. These results suggested that AZ is useful
for regulation of bone metabolism as pharmaceutical products.
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Regeneration induction therapy based on
functional biomaterials with growth factor delivery
Masaya Yamamoto and Yasuhiko Tabata
Department of Biomaterials, Institute for Frontier Medical Sciences, Kyoto University
Tissue engineering is a newly emerging biomedical form to create a local
environment which enables stem cells to promote their proliferation and
differentiation for induction of tissue regeneration. Growth factor is a biosignaling protein that can regulate those cell
functions in the local environment to regulate and accelerate tissue
regeneration. For the successful growth factor-induced tissue regeneration,
it is important to develop functional biomaterials which can function not
only as a scaffold to support the proliferation and differentiation of stem
cells but also as a drug delivery system (DDS) to achieve the appropriate
timing and concentration of growth factors at a body site to be regenerated.
This paper overviews the recent development and clinical application of
functional biomaterials with growth factor delivery necessary to realize the
induction therapy of tissue regeneration.
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Development of apatite-fiber scaffolds and
their application to bone regeneration
Mamoru Aizawa1) and Morio Matsumoto2)
1)Department of Applied Chemistry, School of Science and Technology, Meiji
University
2)Department of Orthopaedic Surgery, School of
Medicine, Keio University
We have successfully developed the apatite-fiber scaffolds (AFS) with
inter-connected pores of 100-250 ?m for tissue engineering of bone. The cells
three-dimensionally cultured using the present scaffolds indicated higher
cell activities, such as cell proliferation and differentiation than the
two-dimensionally cultured cells. An in vivo study using rat models showed
that the AFS had higher ability to perform the bone formation than
commercially available, porous apatite ceramics. In this symposium, we will
describe the development of the AFS with enhanced mechanical property and the
results of in vivo evaluation using rabbit model as our recent works,
together with the explanation of the current AF.
[1] M. Aizawa, H. Shinoda, H. Uchida,
I. Okada, T. J. Fujimi, N. Kanazawa, H. Morisue, M. Matsumoto and Y. Toyama, Phosphorus Res.
Bull., 17 262-268(2004).
[2] H. Morisue, M. Matsumoto, K. Chiba, H.
Matsumoto, Y. Toyama, M. Aizawa, N. Kanzawa, T. J. Fujimi, H.
Uchida, I. Okada, Spine, 31, 1194-2000(2006).
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Enhancement of osteoconductivity
and bioabsorbability of bone substitutes using
partial dissolution-precipitation treatment
Yuichiro Abe
Department of Orthopaedic Surgery, Hokkaido University Graduate School of Medicine
Bone grafting is a commonly used procedure in orthopedic surgeries, and
synthesized hydroxyapatite is mainly used as a bone
substitute. Synthesized hydroxyapatite has a lower osteoconductivity and bioabsorbability
compared to autologous bone graft, however, remains
a serious problem. In this session, I show the favorable effect of partial
dissolution-precipitation treatment on osteoconductivity
and bioabsorbability of hydroxyapatite
materials using animal models.
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Dentin as biomaterial- A case of immediate autograft of dentin and tooth -
Masaru Murata
Oral and Maxillofacial Surgery, School of Dentistry, Health Sciences
University of Hokkaido.
Demineralized dentin matrix (DDM) is an osteoinductive, insoluble collagenous
material. DDM granules derived from a vital tooth were absorbed and remodeled
by new bone in tooth cavity revealing osteosclerosis.
The basic researches of human DDM and a clinical study of immediate autograft of DDM granules and a tooth, using our
developed machines, will be introduced in this symposium.
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Reconstruction of tissue-engineered bone
using an apatite-fiber scaffold and a radial-flow bioreactor and its
biological evaluation
Jun Fukasawa1), Yumiko Nakada1),
Haruka Maehashi2), Tomokazu
Matsuura2), and Mamoru Aizawa1)
1)Department of Applied Chemistry, School of Science and Technology, Meiji
University
2)Division of Central Clinical Laboratory, Jikei
University Hospital
We have successfully developed porous apatite-fiber scaffolds (AFSs) which have three-dimensional (3D) inter-connected
pores using single-crystal apatite fibers and carbon beads; subsequently, we
have clarified that the AFSs have an excellent
bioactivity on the basis of both in vitro and in vivo evaluations [1, 2]. In
present study, in order to create the tissue-engineered bone with three-dimensional
(3D) structure, we carried out 3D-cell culture of mesenchymal
stem cells derived from rat bone marrow using the AFS settled into the
radial-flow bioreactor. Some properties of the resulting tissue-engineered
bone was examined through the histological and
biochemical evaluations.
[1] M. Aizawa, H. Shinoda,
H. Uchida, I. Okada, T. J. Fujimi, N. Kanazawa, H. Morisue, M. Matsumoto and Y. Toyama, Phosphorus Res.
Bull., 17 262-268(2004).
[2] H. Morisue, M. Matsumoto, K. Chiba, H.
Matsumoto, Y. Toyama, M. Aizawa, N. Kanzawa, T. J. Fujimi, H.
Uchida, I. Okada, Spine, 31, 1194-2000(2006).
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Bone formation by porous chitosan
/HAp nanocomposites with
BMP-2 on rat parietal bone
Naoki Harada1), Haruhiko Kashiwazaki1), Tadashi Iizuka2
), Makoto Demura3), Tomoyasu Aizawa3), Masaru
Murata4), Junzo Tanaka5) and
Nobuo Inoue1)
1) Department of Gerodontology,Hokkaido University
2) Support Section for Education and Research, Division of Oral Health
Science, Graduate School of Dental Medicine,Hokkaido
University
3)Faculty of Advanced Life Science, Hokkaido University,
Division of Oral and Maxillofacial Surgery,Hokkaido
University
4)Department of Human Biology and Pathophysiology,
Health Sciences University of Hokkaido ,
5)Department of Metallurgy and Ceramics Science, Tokyo Institute of
Technology
Porous chitosan /HAp nanocomposites with BMP-2 were implanted beneath the
cranial periosteum of 4-week-old SD rats to assess
bone development. At 4 weeks after implantation, the composites with BMP-2
resulted in active bone formation, whereas the composites alone showed no
bone formation. These results suggested that the nanocomposite
with BMP-2 was an effective biomaterial with osteoinductivity
as an onlay graft substitute.
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Interaction between proteins and carbon nanotubes: analyses by column chromatography and
aggregation meter
Yoshinori Kuboki1), Hiroko Takita2), Ryuichi
Fujisawa3), Takamitsu Koshikawa4), Shigeaki Abe4), Tsukasa Akasaka4), Motohiro
Uo4), Fumio Watari4) Min-ho Lee 5),
1)Emeritus Professor, Hokkaido University
2)Support Section for Education and Research, Hokkaido University
3)Department of Oral Biochemistry and Molecular Biology,
Hokkaido University
4)Department of Biomedical Material and Engineering, Graduate School of
Dental Medicine, Hokkaido University, Japan,Hokkaido
University
5)Institute of oral Bioscience, Chonbuk National
University, Korea
Type I collagen molecules and carbon nanotubes
(CNT) share in their rod-like geometrical structures of nano-scale
level. This similarity suggested us the unique interactions between both
substances under certain circumstances. Actually, we previously discovered
that strong aggregation occurred when native collagen was mixed CNT, but not
the denature collagen (gelatin) (Bio-Medical Materials and Engineering 19:
3-9, 2009). This phenomenon was further analyzed in the present study by
applying chromatographic methods, leading many interesting findings.
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Clinical evaluation of masticatory
restration with dental implant for total edentulous
maxilla and mandible.
Eizaburo Kobayashi1),Kazuhisa Mori1),Izumi
Mataga1),Fumihiko Watanabe2)
1)Department of Oral and Maxillofacial Surgery, School of Life Dentistry
at Niigata,The Nippon Dental University
2)Department of Crown and Bridge, School of Life Dentistry at Niigata,The Nippon Dental University
In recent, masticatory function become better by
improvement of stability of proshtetic devices
placed on the dental implant. In this report, clinical evaluation for these
patients who were treated in our department by prosthetic reconstruction
using dental implant were retrospectively performed.
Thirty-one total edentulous patients from total number of all 307 patients
who were installed dental implant in the Niigata Hospital, School of Life Dentistry at Niigata, The Nippon Dental
University for 19 years from 1989 through 2008 were respectively discussed.
In these 31 patients, 15 were males and 16 were females, aged from 42 to 70
years old, average of 60.7. According to a location installed implants,
maxilla was 12 and mandible was 23. Both edentulous maxilla and mandible was
4 patients.
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Clinical study of sinus floor augmentation
with b-tricalcium phosphate
Hiroyuki Kitajo, Takeo Maita, Hiroki Nagayasu, Junichi
Tazaki1), Masaru Murata2),Makoto Arisue2), Takanori
Shibata1)
1)Institute of personalized medical Science, Oral and Maxillofacial
Surgery, Health Sciences University of Hokkaido
2)Reconstructive Surgery for Oral and Maxillofacial Region, Health Sciences
University of Hokkaido
Maxillary sinus augumentation is a method of
attaining sufficient bone height for posterior maxillary implant placement.
The excellent biocompatibility of calcium phosphate ceramics has lead to
their extensive use as biomedical materials. Beta-tricalcium
phosphate (β-TCP) appears to be advantageous in comparison to HAp for the property of absorption with bone remodeling.
In this study, 52-year-old femalepresented with
atrophied upper jaw was performed sinus floor augmentation with β-TCP and Platelet Rich Plasma (PRP). At 6
months after implantation, the place of bone augmentation was trephined and investigated clinically and pathologically.
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Bisphosphonate-related Osteonecrosis
of the Jaw - case report -
Yu-Feng Huang1), Jie
Yang2), Ming-Yung Chou1)
1)Oral Medicine Center, Chung Shan Medical University Hospital, Taichung, Taiwan
2)Oral maxillofacial Radiology, School of Dentistry, Temple University,
Philadelphia, PA, USA
Bisphosphonates were developed in the 19th
century, but were first investigated in the 1960s for use in disorders of
bone metabolism. The initial rationale for their use in humans was their
potential in preventing the dissolution of hydroxylapatite,
the principal bone mineral, and hence arresting bone loss by inducing
apoptosis in osteoclasts and monocytic
precursor cells. After decades of use, many side effects have been reported
including osteonecrosis of the jaw. Here we
reported a case of bisphosphonate-related osteonecrosis which we analyzed with cone-beam CT.
Patient is a 76 y/o male who was diagnosed as prostate cancer 2 years ago
with bone metastasis. He has been receiving ZometaR
injection once a month for 12 months. He had had #43, #44 extracted at local
dental clinic due to severe mobility one month ago. A few days later, he developed
painful swelling at right mandibular body region.
At the time of examination, there was only #34 retained in the mouth.
Significant swelling of right mandible was noted with abscess draining from
the mandible. A bony hard swelling was observed at right inferior border of
chin. Cone-beam CT was performed and the images were analyzed
with Cybermed’s Ondemand
3D. All features are consistent with bisphosphonate-related
osteonecrosis with secondary infection. Continuous
antibiotic was provided for 10 days and pus discharge was reduced
significantly and not painful, but the swelling of mandible remained. Due to
the wide extent of the osteonecrosis and patient’s
status, surgical debridement was not recommended.
Patient is still on weekly follow up.
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Proteins in enamel lamella of porcine mature
enamel
Rumi Nakamura1), Ryuji Yamamoto2), Makoto Fukae2),
Yasuko Momoi1)
1)Department of Operative Dentistry, Tsurumi
University School of Dental Medicine
2)Department of Biochemistry, Tsurumi University School of Dental Medicine
The purpose of this study is to investigate the components and formation
processes of enamel lamella of porcine mature enamel after demineralization
with 0.5M acetic acid. SDS electrophoresis, Mass spectrometry and Western
blotting analysis showed that the structure contained a lot of proteins, in
which the blood derived proteins such as albumin, hemoglobin and their
degradation products were mainly resided. Since the degradation products were
observed in the low-molecular area after electrophoresis, it was considered
that the blood derived proteins were not contamination of
the blood during sample preparation, but were original component of
the products. In addition of them, there were a small amount of enamel
proteins, collagen and DSPP.
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Histological study of new CaTiO3-aC coating
material ?in vivo study-
Ryo Tamamura1), Miho Inoue1), Yasuhisa Hirata1),2), Midori Kubota1), Shin
Takagi2), Etsuo Kishimoto3), Tohru
Takagi1), Masahisa Inoue4), Hitoshi Nagatsuka1) and
Noriyuki Nagai1)
1)Department of Oral Pathology and Medicine, Tokushima Bunri
University
2)Department of Oral and Maxillofacial Reconstructive Surgery,Tokushima
Bunri University
3)Department of Oral Health, Tokushima Bunri
University
4)Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama
University, Laboratory for Structure and Function, Faculty of Pharmaceutical
Sciences, Tokushima Bunri University
In this study, the objective was to evaluate the effect of CaTiO3-aC
coating material on bone tissue by in vivo study. Titanium bars with
CaTiO3-aC coating or HA coating or without coating as a control were
implanted in rat tibias. After 1 and 2 weeks post implantation, implants were
removed with surrounding bone tissue and histological examination was performed.
In the experimental group, plenty of new bone formation
around titanium were observed as compared with control. Especially, in
CaTiO3-aC coating group, the implant was in contact with new bone. Our
results suggest that CaTiO3-aC plays a dominant effect on tissue response,
which could be considered as an important biomaterial for dental implants.
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The influences of Colloidal Platinum Nanoparticles on resin/ root dentin adhesion using
4-META/MMA-TBB resin.
Futami Nagano1), Kazuhiko Endo1), Masanori Hashimoto1),
Hidehiko Sano2), Yusei Miyamoto3), Hiroki Ohno1)
1)Biomaterials and Bioengineering, Health Sciences University of Hokkaido
2)Restorative Dentistry, Hokkaido University
3) Integrated Biosciences, Graduate School of Frontier Sciences, University of
Tokyo
Our previous studies showed that pre-treatments of coronal dentin surface
with Colloidal Platinum Nanoparticles (CPN)
significantly improved the bond strength between SuperBond
C&B (4-META/MMA-TBB) and coronal dentin. The aim of this study is to evaluate
the influence of the pre-treatment with CPN on resin/ root dentin adhesion
using SuperBond C&B. The pre-treatments were
performed as following. Control: Etching with 10-3 solution. Etch-CPN:
Etching then CPN application. CPN-Etch: CPN application then etching. After
PMMA blocks were adhered by SuperBond C&B,
specimens were kept in 37℃ water for 24 h and
they were exposed to the micro tensile bond strength test. The results of the
bond strength showed no significant difference between 3 groups.
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Nicotine and LPS increase MMPs and tPA production and
decrease TIMPs production in osteoblasts
Tomoko Katono1), Takayuki Kawato1),3), Natsuko
Tanabe1), 3), Hideki Tanaka*,Takafumi Iida1), Masafumi Motohashi1), 3), Naoto Suzuki2),3), Kichibee Otsuka2),3), Masao Maeno1),3)
1)Departments of Oral Health Sciences,Nihon
University School of Dentistry
2)Biochemistry, Nihon University School of Dentistry, Nihon University School
of Dentistry
3Division of Functional Morphology, Dental Research Center, Nihon University
School of Dentistry
The arm of this study is to investigate the effect of nicotine and/or LPS
on turnover in osteoid by osteoblasts.
Nicotine and/or LPS increased MMP-1, -2, and -3 and tPA
production; decreased TIMP-1, -3, and -4 production. In the presence of D-tubocurarine or polymyxin B,
neither nicotine nor LPS stimulated MMP-1 production. In the presence of
NS398 or celecoxib, the stimulatory effects of
nicotine and LPS on MMP-1 production were unchanged, but they were unable to
stimulate PGE2 production. These results suggest that nicotine and LPS
stimulate the resorption process that occurs during
turnover of osteoid. Furthermore, they suggest that
the stimulatory effect of nicotine and LPS on PGE2 production is independent
of their stimulatory effect on MMP-1 production.
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Mechanical stress induces osteoclast differentiation via PGE2 production in osteoblasts
Rina Sanuki1), Narihiro
Mitsui1), Masao Maeno2), 3), Naoto Suzuki3), 4), Kichibee
Otsuka3), 4), Hideki Tanaka2), Yuki Koyama1), Chieko Shionome1), Fan Zhang6),
Noriyoshi Shimizu, 1),5)
1)Departments of Orthodontics, Nihon University School of Dentistry
2)Oral Health Sciences,Nihon University School of
Dentistry
3)Biochemistry, Nihon University School of Dentistry
4)Divisions of Functional Morphology,Nihon
University School of Dentistry
5)Clinical Research, Nihon University School of Dentistry
6)Dental Research Center, Nihon University School of Dentistry and
Departments of Orthodontics, Shandong University School of Dentistry
The present study was undertaken to examine the effect of mechanical
stress (MS) on PGE2, COX-2, M-CSF, RANKL, and OPG production in osteoblasts, and to examine the indirect effect of MS on osteoclast differentiation. Osteoclast
differentiation was estimated using TRAP staining of osteoclast
precursors cultured with conditioned medium from MS-treated osteoblasts. As MS increased, PGE2, COX-2, M-CSF, and
RANKL production increased, whereas OPG production decreased. The number of
TRAP-positive cells increased as MS increased. Celecoxib
blocked the stimulatory effect of MS. These results suggest that MS induces osteoclast differentiation by increasing M-CSF and RANKL
production and decreasing OPG production via PGE2 in osteoblasts.
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Establishment of odontoblastic
stem cells producing extracellular matrix under in
vitro condition
Hidetsugu Tsujigiwa1), Naoki Katase2), Eiki Yamachika3), Hitoshi Nagatsuka2), Andrea P.
Rodriguez2), Hidemitsu Harada4), Masao Yamada1)
1)Department of Virology, Graduate School of Medicine, Dentistry and
Pharmaceutical Sciences, Okayama University
2)Department of Oral Pathology and Medicine,Graduate
School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University
3)Department of Oral and Maxillofacial Reconstructive Surgery,Graduate
School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University
4)Department of Oral Anatomy II, School of Dentistry, Iwate Medical
University
We have established odontoblastic stem cells (OSC)
from the dental pulp cells of GFP transgenic rats. OSC showed increased ALP
activity, production of dentin related proteins and positive reaction for
alizarin red staining, and produced extracellular
matrix when cultivated in the presence of b-GP. Co-culture of OSC and ameloblastic stem cells (ASC) demonstrated that OSC
facilitated calcification of ASC. Moreover, OSC formed dentin-like calcified
tissue in vivo when transplanted into dorsal subcutaneous tissue of
immune-deficient mice. All the results suggested that this established OSC
possessed same biological characters as OSC in vivo, and thought to be useful
for tooth regeneration researches and elucidation of cell differentiation
mechanism in odontogenesis.
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IL -1b suppresses the formation of osteoclasts by increasing OPG production via an autocrine mechanism involving celecoxib-related
PGs in chondrocytes
Yusuke Watanabe1), Yukiko Aida1, 4), Masao Maeno3),4) , Nakayama Go1),Naoto
Suzuki2), 4), Kichibee Otsuka2), 5), Hideo
Matsumura1), 4)
1)Departments of Fixed Prosthodontics, Nihon
University School of Dentistry
2)Biochemistry, Nihon University School of Dentistry
3)Oral Health Sciences, Nihon University School of Dentistry
4)Divisions of Advenced Dental Treatment, Nihon
University School of Dentistry
5)Functional Morphology, Dental Research Center, Nihon University School of
Dentistry
We examined the effect of IL-1β and/or celecoxib on
the expression of M-CSF, RANKL, and OPG in human chondrocytes,
and the indirect effect of IL-1β on osteoclast-like
cell formation using RAW264.7 cells. OPG and RANKL expression increased with
IL-1β, whereas M-CSF expression decreased. Celecoxib
blocked the stimulatory effect of IL-1β on OPG and RANKL expression.
Conditioned medium from IL-1β-treated chondrocytes
decreased TRAP staining. These results suggest that IL-1β suppresses the
formation of osteoclast-like cells via increased
OPG production and decreased M-CSF production in chondrocytes,
and OPG production may increase through an autocrine
mechanism involving celecoxib-related PGs.
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IL-17 suppresses the expression of proteases
and differentiation in osteoclast precursors
Satoshi Kitami1),
Hideki Tanaka1), Takayuki Kawato1),3), Natsuko
Tanabe1),3), Akiko Kuwabara1), Toyoko Morita1), Masafumi Motohashi1),3), Naoto Suzuki2),3), Kichibee Otsuka2), 3), Masao Maeno1), 3)
1)Departments of Oral Health Sciences, Nihon University School of
Dentistry
2)Biochemistry, Nihon University School of DentistryHealth
Sciences University of Hokkaido
3)Division of Functional Morphology, Dental Research Center, Nihon University
School of Dentistry
The arm of this study is to investigate the effect of IL-17 on osteoclast differentiation and the expression of carbonic
anhydrase II (CA2), MMP-9, and cathepsin
K (CK) using RAW264.7 cells as osteoclast
precursors. RAW264.7 cells were cultured with or without IL-17 in the
presence of soluble RANKL for up to 10 days. TRAP-positive cells were
detected on day 5 of culture, and the number of the cells decreased by the
addition of IL-17. The gene expression of CA2, MMP-9 and CK in the cells also
was decreased by the addition of IL-17 on day 5 of culture. These results
suggest that IL-17 suppresses osteoclast
differentiation and the function by decreasing of CA2, MMP-9, and CK.
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Mesenchymal stem cell-like potential of periodontal
ligament fibroblasts to construct vascular cell-specific marker-positive
blood vessel structure with a lumen
Naoto Okubo1),2),3), Masato Tamura2), Tadashi Iizuka4), Masaharu
Kamo1), Seiko Kyakumoto1), Naoyuki Chosa1), Noriko
Takahashi1), Yoshimasa Kitagawa2), and Akira
Ishisaki1)
1)Department of Biochemistry, Iwate Medical University, School of
Dentistry, Hokkaido University
2)Department of Oral Biochemistry and Molecular Biology, Division of Oral
Health Science,Hokkaido University
3)Department of Oral Diagnosis and Oral Medicine, Division of Oral Pathobiological Science, Hokkaido University
4)Support Section for Education and Research, Graduate School of Dental
Medicine, Hokkaido University
Objective: To evaluate whether fibroblasts derived from periodontal ligament
(PDL) retain the ability to differentiate into putative vascular cells and
construct blood vessel structures.
Methods: Single cell-derived cultures (SCDCs) were
established from primary rat PDL fibroblast cultures, and their expression of
mesenchymal stem cell (MSC)-
and endothelial cell (EC)-markers was evaluated by RT-PCR. The ability to
construct a blood vessel structure was evaluated in three-dimensional
cultures. The morphological and immunohistological
characteristics of the structure were then evaluated.
Results: Each SCDC expressed EC in addition to MSC markers. SCDC2 cells,
which abundantly expressed Tie-2, vigorously constructed a blood vessel
structure.
Conclusion: PDL fibroblasts have the potential to construct an EC
marker-positive blood vessel-like structure.
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Tissue regeneration using rhPDGF-BB with gelatin sponge
Atsushi Niida1), Yukito Hirose1), Morio Ochi1), Masaru Murata2), Tohru
Kaku3)
1)Division of Fixed Prosthodontics and Oral Implantology, Department of Oral Rehabilitation, Health
Sciences University of Hokkaido
2)Division of Oral and Maxillofacial Surgery, Health Sciences University of
Hokkaido
3)Division of Clinical Oral Pathology, Department of Human Biology and Pathophysiology, School of Dentistry, Health Sciences
University of Hokkaido
After bone augmentation using biomaterials, the failure of the suture
sometimes occurs. The aim of this study is to achieve the conglutinant
suture part, because there are troubles on the microcirculation and tension
between tissue of suture part and mucosa membrane. Three by 4 mm in size of
cross-linked gelatin sponges were inserted into Teflon tube. After that, 10?ng of diluted rhPDGF-BB was
dripped on them and implanted into the subcutaneous tissue of 8-month-male
rats’ back. After 2 weeks, the materials were explanted and microscopically
observed. In the PDGF group, the fibrous tissue invaded into sponge, while
the tissue invasion in the sponge alone group was not seen. In these results,
PDGF sponges may be useful for the tissue regeneration.
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Enhancement by the peptide hydrogel of osteogenesis
induced by rhBMP-2 in rats
Hiroko Takita1),
Tadashi Iizuka1), Yoshinori Kuboki2)
1)Support Section for Education and Research, Graduate ,Hokkaido
University
2)School of Dental Medicine, Hokkaido University
Hokkaido University
The aim of this study is to investigate the effect of the peptide hydrogel (PH) on BMP-induced ectopic
bone formation. The peptide hydrogel can compose
optimal 3D spaces. A fibrous glass membrane as a BMP carrier was mixed with
PH and BMP-2. The mixed composites were implanted into rats subcutaneously.
The results showed that Ca and osteocalcin contents
of PH/BMP implants were higher than those of BMP implants at 3 weeks after
implantation. It is concluded that the BMP-induced bone formation depends
upon the geometry of the carrier, which can be constructed with PH.
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A case of calcifying epithelioma
in cheek region with osteocyte and bone formation -
hard tissue-related genetic analysis-
Kaoru Kusano1), Katsutoshi Ito1), Jun Hino1),
Masaru Murata1), Hiroki Nagayasu2) , Yoshihiro Abiko2) , Tohru
Kaku3) Takanori Shibata4) and Makoto Arisue1)
1) Oral and Maxillofacial Surgery, Health Sciences University of Hokkaido
2) Institute of Personalized Medical Science, Health Sciences University of
Hokkaido
3 Clinical Oral Pathology, Health Sciences University of Hokkaido
4 Reconstructive Surgery for Oral and Maxillofacial Region, Health Sciences
University of Hokkaido
Calcifying epithelioma is a benign tumor derived
from hair-matrix cells, a rare lesion in the oral and maxillofacial regions.
The patient was a 33 years old female, who was aware of a consistent painless
tumor in the right cheek for 20 years. The tumor was of bone-like hardness
and immobile under the skin with the size of the tip of the little finger.
The clinical diagnosis was calcifying epithelioma,
and tumorectomy was performed under local
anesthesia and intravenous sedation. The histopathological
findings of the tumor revealed shadow cells with osteocytes
and bone formation. Based on clinical and histopathological
findings, the patient was diagnosed with a calcifying epithelioma.
Total RNA was extracted from the removed tumor. Hard tissue-related gene
expressions(BMP-2,ALP,OPN,OCN)were determined by RT-PCR, and hard tissue-related mRNA expressions
were observed in the removed tissue. These results indicated that hard
tissue-related mRNA is associ
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Application of the adipose tissue-derived
stem cell to the bone tissue engineering
Masanori Takekawa, Mituyoshi
Matsuda, Eiji Kondoh and Hiroya Ito
Department of Oral and Maxillofacial Surgery, Asahikawa Medical College
The aim of this study is to assess the usefulness of adipose tissue-derived
stem cells(ADSCs) for bone
tissue engineering. Collagen sponges(CS) with ADSCs were cultured in osteogenic
differentiation medium. At the 2nd week of the culture, the samples were
implanted to rat’s subcutaneous tissues. 4 weeks after implantation, samples
were examined. For the control, cells were cultured without osteogenic differentiation medium. A large quantity of
newly formed bone was observed in the inside of CS. In the control, new bone
formations were not observed. The results suggested that the adipose
tissue-derived stem cell was useful for bone regenerative medicine.
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Effects of IL-6 and sIL-6R on turnover of
bone and cartilage matrix proteins in chondrocytes
Kazuhiro Honda1), Yukiko Aida1),3), Masao Maeno2), 5), Yusuke Watanabe1), Shihoko Tanigawa1), Suzuki Naoto3),5), Kichibee Otsuka3), 5), Hideo Matsumura1), 4)
1)Departments of Fixed Prosthodontics, Nihon
University School of Dentistry
2)Oral Health Sciences,Nihon University School of
Dentistry
3)Biochemistry, Nihon University School of Dentistry
4)Nihon University School of Dentistry, Divisions of Advanced Dental Treatment,
Nihon University School of Dentistry
5)Functional Morphology, Dental Research Center, Nihon University School of
Dentistry
We examined the effect of IL-6 and soluble IL-6 receptor (sIL-6R) on the
expression of MMPs, PAs
and their inhibitors (TIMPs and PAI-1) in human chondrocytes. By the addition of IL-6 and sIL-6R, the
expression of MMP-1, -3, -13 and TIMP-1 increased for the culture period of
28 days; the expression of MMP-1, -13 and TIMP-1 increased markedly. The
expression of TIMP-2, -3 and -4 increased after days 7 or 14 of culture. On
the other hand, MMP-2 and uPA expression decreased
for the culture period of 28 days and tPA
expression decreased after day 14 of culture. These results suggest that IL-6
and sIL-6R stimulate turnover of bone and cartilage matrix proteins by
increasing collagenases and TIMP-1 in chondrocytes, and also that plasminogen/plasmin
systems in the cells are not related in the turnover.
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Compressive force stimulates the expression
of IL-17s and their receptors in osteoblastic
MC3T3-E1 cells
Fan Zhang1), Yuki Koyama1, Masao Maeno2),4), Narihiro
Mitsui1), Chieko Shininime1), Kotoe Mayahara1), 5),
Naoto Suzuki3),4), Kichibee Otsuka3),4), Noriyoshi Shimizu1), 5)
1)Departments of Orthodontics,Nihon University
School of Dentistry
2)Oral Health Sciences,Nihon University School of
Dentistry
3)Biochemistry, Nihon University School of Dentistry
4)Nihon University School of Dentistry, Divisions of Functional Morphology,Nihon University School of Dentistry
5)Clinical Research, Dental Research Center, Nihon University School of
Dentistry
Recently, interleukin (IL)-17 was found to stimulate osteoclastic
resorption via osteoblasts
by inducing RANKL expression. We examined the effect of compressive force on
the gene expressions of IL-17A, IL-17B, IL-17C, IL-17D, IL-17E, IL-17F, and
their receptors (IL-17RA, IL-17RB, IL-17RC, IL-17RD, and IL-17RE) using
MC3T3-E1 cells as osteoblasts. The expression
levels of IL-17s and their receptors increased depending on the compressive
force. These results indicate that mechanical stress induces the expression
of IL-17s and their receptors in osteoblasts, and
that IL-17s and their receptors produced in response to mechanical stress may
affect osteoclastgenesis via RANKL expression.
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Radiographic Demonstration of the Soft
Tissue Using the New Type of Source of X-ray PXR
Yasuko Numata1),Toshiro Sakae1), Hirotsugu
Yamamoto1), Takasi Kaneda1), Jin Yamamoto1), Isamu
Sato2),Yasushi Hayakawa3),Yumiko Takahashi3), Kyoko Nogami3)
1)Nihon University School of Dentistry at Matsudo,
2)Nihon University Graduated School,
3)Laboratory for Electron Beam Research and Application of Nihon University.
This study aimed to take X-ray photographs of soft tissue, which was
difficult to do with conventional X-rays, using a new X-ray source of PXR
(Parametric X-ray) generated in LEBRA. At first the hard tissue was
photographed by direct imaging and was able to get clear radiograph, showing
the PXR has ability for such purpose. Applying a phase contrast imaging for
soft tissues and/or materials composed of light elements using the PXR
resulted in good appearance of images, whereas it is difficult to do so by a
conventional white X-rays. In future, developing these characteristics of
LEBRA-PXR may introduce a great improvement in diagnosis and treatment in the
medical scene. (Supported in part by Nihon University Multidisciplinary
Research Grant for Sogo 09-024, 2009)
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Elemental Analysis of Arsenic Using a
Wavelength-Tunable Parametric X-ray
T. Sakae1), T. Hayakawa1), K. Suzuki1), Y. Tanimoto1), H. Nakada1), I. Sato2), T. Shintomi2),H.
Yamamoto3), K. Suzuki3), N. Iwata3), T. Tanaka4), K. Hayakawa4), Y.
Hayakawa4), Y. Takahashi4), T. Kuwada4)
1)Nihon Univ. Sch. Dent. at
Matsudo,
2)Nihon Univ. ARISH,
3)Nihon Univ. College of Science and Technology,
4)Nihon Univ. LEBRA,
Arsenic is known as not only valuable element used in GaAs
semiconductor, but as harmful for human body. Tolerance of human intake is
0.05 mg/kg/day. Analysis of As is usually carried out using Atomic Absorption
Analysis or LC-ICP/MS, but these techniques do not allow in vivo analysis.
Using a wavelength-tunable Parametric X-ray generated at LEBRA, Nihon University, the X-ray absorption edge for As in realgar was clearly detected. Applying this PXR for radiography
may be able to detect and quantify the harmful heavy metals in human body.
(Supported by Nihon University Multidisciplinary Research Grant for Sogo09-024, 2009)
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Studies on the distribution of acellular and cellular cementum
in human permanent teeth
Hitoshi Yamamoto, Toshihide Niimi,
Rumi Yokota-Ohta, Kunihiro Suzuki, Toshiro Sakae, Yukishige
Kozawa
Department of Histology, Cytology and Developmental Anatomy,
Nihon University School of Dentistry at Matsudo
Cementum is divided into acellular
and cellular cementum. It is generally known that acellular cementum is located
on the cervical portion and cellular cementum
distributes both on the apical portion and furcation
area. In fact, however, acellular and cellular cementum are
distributed irregularly. The authors observed grinding sections of extracted
human teeth (50 incisors and 78 molars) by light microscopy. As a result, the
distribution of acellular and cellular cementum showed a variety of patterns as well as the
typical distribution pattern.
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HSP27 expression in malignant transformation
of ameloblastoma
Keisuke Nakano1), Chong Huat
Siar2) and Toshiyuki Kawakami1)
1)Hard Tissue Pathology Unit, Matsumoto Dental
University Graduate School of Oral Medicine,
2)Department of Oral Pathology, Faculty of Dentistry, University of Malaya
Heat shock protein (HSP) expression caused by various kinds of stress and HSP
is responsible for cytological regulation of cell differentiation,
proliferation and/or morphogenesis. In this research, we examined HSP27
peptide in both ameloblastoma and ameloblastic carcinoma. After histopathological
examination, the distribution of HSP27 was examined by immunohistochemistry
(IHC) using anti-human HSP27 monoclonal antibody. Ameloblastoma
showed strong HSP27 reactivity in columner and polyhedral
tumor cells. In the other hand, ameloblastic
carcinoma showed HSP27 reactivity in atypical tumor cells. These results
suggest that HSP27 plays some role in cytological differentiation and
progression of malignant transformation in ameloblastoma.
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Expression of heparanase
in odontogenic cystic lesions
Hiroyuki Matsuda1), Naoki Katase1), Hidetsugu
Tsujigiwa2), Gul San Ara
Sathi1), Masae Fujii1), Mathieu Lefeuvre1), Han
Liu3), Ryo Tamamura1) and Hitoshi Nagatsuka1)
1)Department of Oral Pathology and Medicine ,, Okayama University
2)Department of Virology, Graduate School of Medicine, Dentistry and
Pharmaceutical Sciences, Okayama University,
3)Department of Oral Biology, College of Stomatology,
Dalian Medical University
The aim of this study was to clarify the expressions of heparanase
protein and gene in odontogenic cystic lesions. Heparanase expressions in follicular cysts (FC), radicular cysts (RC), keratocystic
odontogenic tumors (KCOT) and ameloblastomas
(unicystic type, A-U) were examined by immunohistochemistry and in situ hybridization. In all
cystic lesions except RC, the heparanase
expressions were observed in epithelial component. Intense gene expression
was observed in KCOT associated with naevoid basal
cell carcinoma syndrome compared with sporadic ones. These results suggest
that heparanase may play a role of tumor growth
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Effect of oral administration of statin on bone regeneration process in ovariectomized rat
Hata Saya1), Tohru
Hayakawa2), Makiko Ono1), Hirotsugu Yamamoto3),
Yoshiaki Akimoto1)
1)Department of Oral Surgery,Nihon Univeresity School of Dentistry at Matsudo
2)Department of Dental Biomaterials,Nihon Univeresity School of Dentistry at Matsudo
3)Department of Oral Pathology, Nihon Univeresity
School of Dentistry at Matsudo
It has been reported that simvastatin (SV),
which is a cholesterol synthesis inhibitor and a therapeutic drug for hypercholesteremia. The purpose of this study is to
evaluate the efficacy of oral administration of SV on the bone healing
process in the cortical bone defects of the tibiae of ovariectomized
(OVX) rats. In conclusion, the present results revealed that oral
administration of SV might provide a beneficial effect on bone healing
process for OVX rats.
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