Role of interleukin-6 in orthodontically induced inflammatory root resorption in humans

Ryuichi Kunii,Masaru Yamaguchi,Yasuhiro Tanimoto,Masaki Asano,Kunihiko Yamada,Takemi Goseki,Kazutaka Kasai 대한치과교정학회 2013 대한치과교정학회지 Vol.43 No.6

Objective: To determine the interleukin (IL)-6 levels in gingival crevicular fluid (GCF) of patients with severe root resorption after orthodontic treatment and investigate the effects of different static compressive forces (CFs) on IL-6 production by human periodontal ligament (hPDL) cells and the influence of IL-6 on osteoclastic activation from human osteoclastic precursor (hOCP) cells in vitro. Methods: IL-6 levels in GCF samples collected from 20 patients (15 and 5 subjects without and with radiographic evidence of severe root resorption, respectively) who had undergone orthodontic treatment were measured by ELISA. The levels of IL-6 mRNA in hPDL cells and IL-6 protein in conditioned medium after the application of different uniform CFs (0, 1.0, 2.0, or 4.0 g/㎠ for up to 72 h) were measured by real-time PCR and ELISA, respectively. Finally, the influence of IL-6 on mature osteoclasts was investigated by using hOCP cells on dentin slices in a pit-formation assay. Results: Clinically, the IL-6 levels were significantly higher in the resorption group than in the control group. In vitro, IL-6 mRNA expression significantly increased with increasing CF. IL-6 protein secretion also increased in a time- and magnitude-dependent manner. Resorbed areas on dentin slices were significantly greater in the recombinant human IL-6-treated group and group cultured in hPDL cell-conditioned medium with CF application (4.0 g/㎠) than in the group cultured in hPDL cell-conditioned medium without CF application. Conclusions: IL-6 may play an important role in inducing or facilitating orthodontically induced inflammatory root resorption.

Effect of caspases and RANKL induced by heavy force in orthodontic root resorption

Yukari Minato,Masaru Yamaguchi,Mami Shimizu,Jun Kikuta,Takuji Hikida,Momoko Hikida,Masaaki Suemitsu,Kayo Kuyama,Kazutaka Kasai 대한치과교정학회 2018 대한치과교정학회지 Vol.48 No.4

Objective: Orthodontic root resorption (ORR) due to orthodontic tooth movement is a difficult treatment-related adverse event. Caspases are important effector molecules for apoptosis. At present, little is known about the mechanisms underlying ORR and apoptosis in the cementum. The aim of the present in vivo study was to investigate the expression of tartrate-resistant acid phosphatase (TRAP), caspase 3, caspase 8, and receptor activator of nuclear factor kappa-B ligand (RANKL) in the cementum in response to a heavy or an optimum orthodontic force. Methods: The maxillary molars of male Wistar rats were subjected to an orthodontic force of 10 g or 50 g using a closed coil spring. The rats were sacrificed each experimental period on days 1, 3, 5, and 7 after orthodontic force application. And the rats were subjected to histopathological and immunohistochemical analyses. Results: On day 7 for the 50-g group, hematoxylin and eosin staining revealed numerous root resorption lacunae with odontoclasts on the root, while immunohistochemistry showed increased TRAP- and RANKL-positive cells. Caspase 3- and caspase 8-positive cells were increased on the cementum surfaces in the 50-g group on days 3 and 5. Moreover, the number of caspase 3- and caspase 8-positive cells and RANKL-positive cells was significantly higher in the 50-g group than in the 10-g group. Conclusions: In our rat model, ORR occurred after apoptosis was induced in the cementum by a heavy orthodontic force. These findings suggest that apoptosis of cementoblasts is involved in ORR.[Korean J Orthod 2018;48(4):253-261]

Comparisons of orthodontic root resorption under heavy and jiggling reciprocating forces during experimental tooth movement in a rat model

Takuji Hikida,Masaru Yamaguchi,Mami Shimizu,Jun Kikuta,Tomokazu Yoshino,Kazutaka Kasai 대한치과교정학회 2016 대한치과교정학회지 Vol.46 No.4

Objective: Root mobility due to reciprocating movement of the tooth (jiggling) may exacerbate orthodontic root resorption (ORR). “Jiggling” describes mesiodistal or buccolingual movement of the roots of the teeth during orthodontic treatment. In the present study, buccolingual movement is described as “jiggling.” We aimed to investigate the relationship between ORR and jiggling and to test for positive cell expression in odontoclasts in resorbed roots during experimental tooth movement (jiggling) in vivo. Methods: Male Wistar rats were divided into control, heavy force (HF), optimal force (OF), and jiggling force (JF) groups. The expression levels of cathepsin K, matrix metalloproteinase (MMP)-9 protein, interleukin (IL)-6, cytokine-induced neutrophil chemoattractant 1 (CINC-1; an IL-8-related protein in rodents), receptor activator of nuclear factor κB ligand (RANKL), and osteoprotegerin protein in the dental root were determined using immunohistochemistry. Results: On day 21, a greater number of root resorption lacunae, which contained multinucleated odontoclasts, were observed in the palatal roots of rats in the JF group than in rats from other groups. Furthermore, there was a significant increase in the numbers of cathepsin K-positive and MMP-9-positive odontoclasts in the JF group on day 21. Immunoreactivities for IL-6, CINC-1, and RANKL were stronger in resorbed roots exposed to jiggling than in the other groups on day 21. Negative reactivity was observed in the controls. Conclusions: These results suggest that jiggling may induce ORR via inflammatory cytokine production during orthodontic tooth movement, and that jiggling may be a risk factor for ORR.

Short-Term Changes in Gut Microflora and Intestinal Epithelium in X-Ray Exposed Mice

Tsujiguchi, Takakiyo,Yamaguchi, Masaru,Yamanouchi, Kanako The Korean Association for Radiation Protection 2020 방사선방어학회지 Vol.45 No.4

Background: Gut microflora contributes to the nutritional metabolism of the host and to strengthen its immune system. However, if the intestinal barrier function of the living body is destroyed by radiation exposure, the intestinal bacteria harm the health of the host and cause sepsis. Therefore, this study aims to trace short-term radiation-induced changes in the mouse gut microflora-dominant bacterial genus, and analyze the degree of intestinal epithelial damage. Materials and Methods: Mice were irradiated with 0, 2, 4, 8 Gy X-rays, and the gut microflora and intestinal epithelial changes were analyzed 72 hours later. Five representative genera of Actinobacteria, Firmicutes, and Bacteroidetes were analyzed in fecal samples, and the intestine was pathologically analyzed by Hematoxylin-Eosin and Alcian blue staining. In addition, DNA fragmentation was evaluated by the TdT-mediated dUTP nick-end labeling (TUNEL) assay. Results and Discussion: The small intestine showed shortened villi and reduced number of goblet cells upon 8 Gy irradiation. The large intestine epithelium showed no significant morphological changes, but the number of goblet cells were reduced in a radiation dose-dependent manner. Moreover, the small intestinal epithelium of 8 Gy-irradiated mice showed significant DNA damaged, whereas the large intestine epithelium was damaged in a dose-dependent manner. Overall, the large intestine epithelium showed less recovery potential upon radiation exposure than the small intestinal epithelium. Analysis of the intestinal flora revealed fluctuations in lactic acid bacteria excretion after irradiation regardless of the morphological changes of intestinal epithelium. Altogether, it became clear that radiation exposure could cause an immediate change of their excretion. Conclusion: This study revealed changes in the intestinal epithelium and intestinal microbiota that may pave the way for the identification of novel biomarkers of radiation-induced gastrointestinal disorders and develop new therapeutic strategies to treat patients with acute radiation syndrome.

Comparison of energy expenditure and substrate oxidation between walking and running in men and women

Akitoshi Makino,Keiichi Yamaguchi,Daichi Sumi,Masaru Ichikawa,Masumi Ohno,Kazushige Goto 한국운동영양학회 2022 Physical Activity and Nutrition (Phys Act Nutr) Vol.26 No.1

[Purpose] The present study compared energy metabolism between walking and running at equivalent speeds during two incremental exercise tests. [Methods] Thirty four university students (18 males, 16 females) were recruited. Each participant completed two trials, consisting of walking (Walk) and running (Run) trials on different days, with 2-3 days apart. Exercise on a treadmill was started from initial stage of 3 min (3.0 k/m in Walk trial, 5.0 km/h in Run trial), and the speed for walking and running was progressively every minute by 0.5 km/h. The changes in metabolic variables, heart rate (HR), and rating of perceived exertion (RPE) during exercise were compared between the trials. [Results] Energy expenditure (EE) increased with speed in each trial. However, the Walk trial had a significantly higher EE than the Run trial at speeds exceeding 92 ± 2 % of the maximal walking speed (MWS, p < 0.01). Similarly, carbohydrate (CHO) oxidation was significantly higher in the Walk trial than in the Run trial at above 92 ± 2 %MWS in males (p < 0.001) and above 93 ± 1 %MWS in females (p < 0.05). [Conclusion] These findings suggest that EE and CHO oxidation during walking increase non-linearly with speed, and walking at a fast speed causes greater metabolic responses than running at the equivalent speed in young participants.

Color stability of laboratory glass-fiber-reinforced plastics for esthetic orthodontic wires

Toshihiro Inami,Yasuhiro Tanimoto,Naomi Minami,Masaru Yamaguchi,Kazutaka Kasai 대한치과교정학회 2015 대한치과교정학회지 Vol.45 No.3

Objective: In our previous study, glass-fiber-reinforced plastics (GFRPs) made from polycarbonate and glass fibers were prepared for esthetic orthodontic wires using pultrusion. These laboratory GFRP wires are more transparent than the commercially available nickel-titanium wire; however, an investigation of the color stability of GFRP during orthodontic treatment is needed. Accordingly, in the present study, the color stability of GFRP was assessed using colorimetry. Methods: Preparation of GFRP esthetic round wires (diameter: 0.45 mm [0.018 inch]) using pultrusion was described previously. Here, to investigate how the diameter of fiber reinforcement affects color stability, GFRPs were prepared by incorporating either 13-mm (GFRP-13) or 7-mm glass (GFRP-7) fibers. The color changes of GFRPs after 24 h, and following 1, 2, and 4 weeks of coffee immersion at 37℃, were measured by colorimetry. We evaluated the color stability of GFRPs by two evaluating units: the color difference (ΔE*) and National Bureau of Standards (NBS). Results: After immersion, both GFRPs showed almost no visible color change. According to the colorimetry measurements, the ΔE* values of GFRP-13 and GFRP-7 were 0.73?1.16, and 0.62?1.10, respectively. In accordance with NBS units, both GFRPs showed “slight” color changes. As a result, there were no significant differences in the ΔE* values or NBS units for GFRP-13 or GFRP-7. Moreover, for both GFRPs, no significant differences were observed in any of the immersion periods. Conclusions: Our findings suggest that the GFRPs will maintain high color stability during orthodontic treatment, and are an attractive prospect as esthetic orthodontic wires.

Isolated Tuberculoma Mimicking Foramen Magnum Meningioma in the Absence of Primary Tuberculosis: A Case Report

Manish Kolakshyapati,Masaaki Takeda,Takafumi Mitsuhara,Satoshi Yamaguchi,Masaru Abiko,Shingo Matsuda,Kaoru Kurisu 대한척추신경외과학회 2018 Neurospine Vol.15 No.3

Central nervous system tuberculosis is a devastating complication of systemic tuberculosis. Intradural extramedullary (IDEM) tuberculoma at the foramen magnum is rare, and mimics en plaque meningioma. We report the case of a 53-year-old woman who presented with dysesthesia of the tongue and lower cranial nerve (CN) palsy, with onset 4 months prior to admission. The neurologic examination revealed left upper-limb weakness and hypoesthesia on the sole and dorsum of the left foot. Other physical examinations revealed no features of tubercular infection. Laboratory investigations likewise showed no signs of infection or inflammation. Magnetic resonance imaging of the brain showed an IDEM mass originating from the left intradural surface at the foramen magnum extending to the C2 segment and compressing the brainstem and upper cervical cord. The mass was isointense/hypointense on T1- and T2-weighted images and homogeneously-enhanced on postcontrast images. The lesion also exhibited the dural-tail sign and was preoperatively diagnosed as en plaque meningioma. The patient underwent surgery via the left transcondylar fossa approach with partial laminectomy of the atlas. Intraoperatively, the mass exhibited a dural origin and encased the vertebral artery and lower CNs, with strong adhesions. While the histopathological study of the mass was strongly suggestive of tuberculoma with multifocal granulomas, caseous necrosis, and Langerhans giant cells, extensive diagnostic studies failed to detect Mycobacterium tuberculosis itself. Although the patient had recurrence with multisystem involvement, she responded well to antitubercular treatment. IDEM tuberculoma of the foramen magnum may present as en plaque meningioma. Histopathology is required for a definitive diagnosis. Prompt surgical resection and decompression with adequate antitubercular treatment yield better neurological outcomes.

Structural Characteristics of Epitaxially a- and b-axis-oriented (Bi_(3.25)Nd_(0.75))Ti_3O_(12) Films Fabricated on Conductive Nb:TiO_2 Substrates by High-temperature Sputtering

Akihiro Tamura,Masafumi Kobune,Kazuki Imagawa,Hisashi Oshima,Yusuke Daiko,Atsushi Mineshige,Tetsuo Yazawa,Hiroshi Nishioka,Hironori Fujisawa,Masaru Shimizu,Hideshi Yamaguchi,Koichiro Honda 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.59 No.31

3.0-mm-thick a- and b-axis-oriented (Bi_(3.25)Nd_(0.75))Ti_3O_(12) (BNT-0.75) films were fabricated on conductive Nb:TiO_2(101) (Nb = 0, 0.048, 0.46, 0.79 mass%) single crystal substrates by high-temperature sputtering. A BNT films grown on undoped TiO_2 substrates have no orientation, whereas BNT films deposited on Nb:TiO_2 substrates with 0.46-0.79 mass% Nb show strong (h00/0k0) diffractions and grow with a heteroepitaxial relationship to the underlying Nb:TiO_2 substrates. The BNT-0.75 film deposited on Nb:TiO_2(101) substrate with 0.79 mass% Nb was indicated the peculiar shape of approximately 100-150-nm-thick nanoplates. We speculate that the driving force for producing a plate-like structure for BNT films is attributed to the large anisotropy of linear expansion coefficients for Bi_4Ti_3O12, and the comparatively small lattice matching between Nb:TiO_2 substrate and BNT film.

Fabrication and Characterization of Perovskite (Bi,Sm)(Ni,Ti)O3 Thin Films by Rf Magnetron Sputtering

Hideto Tada,Masafumi Kobune,Koji Fukushima,Hisashi Oshima,Daisuke Horit,Akihiro Tamura,Yusuke Daiko,Atsushi Mineshige,Tetsuo Yazawa,Hironori Fujisawa,Masaru Shimizu,Hideshi Yamaguchi,Koichiro Honda 한국물리학회 2009 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.55 No.2

The structural characteristics, the mechanism of crystal growth, and the ferroelectric properties of partially Sm-substituted perovskite bismuth-samarium-nickel-titanate [(Bi1−xSmx)(Ni0.5Ti0.5)- O3; BSNT, x = 0− 0.9] thin films deposited on Pt(100)/MgO(100) substrates by rf sputtering have been investigated using X-ray diffraction, transmission electron microscope, and polarization - electric field hysteresis loop measurements. The fabricated BSNT samples with x≥0.6 were confirmed to have a single-phase perovskite structure. Of the four samples (x = 0.6 0.7, 0.8, and 0.9) with a single-phase perovskite structure, the c-axis-oriented epitaxial BSNT film with x = 0.9 exhibited the best hysteresis loop, with a remanent polarization of 2 μC/cm2 and a coercive field of 100 kV/cm. The structural characteristics, the mechanism of crystal growth, and the ferroelectric properties of partially Sm-substituted perovskite bismuth-samarium-nickel-titanate [(Bi1−xSmx)(Ni0.5Ti0.5)- O3; BSNT, x = 0− 0.9] thin films deposited on Pt(100)/MgO(100) substrates by rf sputtering have been investigated using X-ray diffraction, transmission electron microscope, and polarization - electric field hysteresis loop measurements. The fabricated BSNT samples with x≥0.6 were confirmed to have a single-phase perovskite structure. Of the four samples (x = 0.6 0.7, 0.8, and 0.9) with a single-phase perovskite structure, the c-axis-oriented epitaxial BSNT film with x = 0.9 exhibited the best hysteresis loop, with a remanent polarization of 2 μC/cm2 and a coercive field of 100 kV/cm.