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Harrison A.,Bioventus | Lin S.,Rutgers University | Pounder N.,Bioventus | Mikuni-Takagaki Y.,Kanagawa Dental University
Ultrasonics | Year: 2016

It has been 30 years since the first level one clinical trial demonstrated low intensity pulsed ultrasound (LIPUS) could accelerate fracture repair. Since 1994 numerous investigations have been performed on the effect of LIPUS. The majority of these studies have used the same signal parameters comprised of an intensity of 30 mW/cm2 SATA, an ultrasound carrier frequency of 1.5 MHz, pulsed at 1 kHz with an exposure time of 20 minutes per day. These studies show that a biological response is stimulated in the cell which produces bioactive molecules. The production of these molecules, linked with observations demonstrating the enhanced effects on mineralization by LIPUS, might be considered the general manner, or mode, of how LIPUS stimulates fractures to heal. We propose a mechanism for how the LIPUS signal can enhance fracture repair by combining the findings of numerous studies. The LIPUS signal is transmitted through tissue to the bone, where cells translate this mechanical signal to a biochemical response via integrin mechano-receptors. The cells enhance the production of cyclo-oxygenese 2 (COX-2) which in turn stimulates molecules to enhance fracture repair. The aim of this review is to present the state of the art data related to LIPUS effects and mechanism. © 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license.

Suzuki H.,Fukuoka University of Education | Yamamoto T.,Kanagawa Dental University
Tissue and Cell | Year: 2014

In this study, we used immunohistochemical techniques to determine the cell type of leucine-enkephalin (Leu-ENK)-immunoreactive cells in the axolotl (Ambystoma mexicanum) pituitary. Immunoreactive cells were scattered throughout the pars distalis except for the dorso-caudal portion. These cells were immuno-positive for luteinizing hormone (LH), but they were immuno-negative for adrenocorticotrophic, growth, and thyroid-stimulating hormones, as well as prolactin. Immunoelectron microscopy demonstrated that Leu-ENK-like substance and LH co-localized within the same secretory granules. Leu-ENK secreted from gonadotrophs may participate in LH secretion in an autocrine fashion, and/or may participate in the release of sex steroids together with LH. © 2013 Elsevier Ltd.

Suzuki H.,Fukuoka University of Education | Yamamoto T.,Kanagawa Dental University
Tissue and Cell | Year: 2014

In this study, we investigated the presence of ovoid or ellipsoidal amylin-immunoreactive cells of the pancreatic islets of the black-spotted frog Rana (Pelophylax) nigromaculata. Using double immunofluorescent staining, all amylin-immunoreactive cells were shown to be immuno-negative for insulin, glucagon, and somatostatin, and they were often observed in peripheral regions of clusters of insulin-immunoreactive cells. Under immunoelectron microscopy, amylin-immunoreactive signals were detected on the secretory granules in a specific type of endocrine cells. From our results, we conclude that the amylin-immunoreactive cells correspond to X cells among the 4 distinct types of endocrine cells (B, A/PP, D, and X) previously identified in the frog. Amylin secreted from X cells may regulate the hormone secretion from A/PP cells and/or B cells through a paracrine mechanism. © 2014 Elsevier Ltd.

Mitsushima D.,Yokohama City University | Mitsushima D.,Kanagawa Dental University | Mitsushima D.,Yamaguchi University | Sano A.,Yokohama City University | Takahashi T.,Yeshiva University
Nature Communications | Year: 2013

Learning induces plastic changes in synapses. However, the regulatory molecules that orchestrate learning-induced synaptic changes are largely unknown. Although it is well established that cholinergic inputs from the medial septum modulate learning and memory, evidence for the cholinergic regulation of learning-induced synaptic plasticity is lacking. Here we find that the activation of muscarinic acetylcholine (ACh) receptors (mAChRs) mediates the contextual fear learning-driven strengthening of hippocampal excitatory pyramidal synapses through the synaptic incorporation of AMPA-type glutamate receptors (AMPARs). Contextual fear learning also enhances the strength of inhibitory synapses on hippocampal pyramidal CA1 neurons, in a manner mediated by the activation of, not mAChRs, but, nicotinic AChRs (nAChRs). We observe a significant correlation between the learning-induced increases in excitatory and inhibitory synaptic strength at individual pyramidal neurons. Understanding the mechanisms underlying cholinergic regulation of learning-induced hippocampal synaptic plasticity may help the development of new therapies for cognitive disorders. © 2013 Macmillan Publishers Limited. All rights reserved.

Iwata T.,Kanagawa Dental University | Kawata T.,Kanagawa Dental University
American Journal of Orthodontics and Dentofacial Orthopedics | Year: 2016

A patient came with left-side temporomandibular arthralgia, limited mandibular opening, frontal facial asymmetry, and a significant anterolateral open bite. Severe alterations in the occlusal and maxillofacial anatomy resulted from an osteochondroma associated with the mandibular condyle. We describe the changes associated with extirpation of the mandibular condylar osteochondroma and subsequent orthodontic treatment. These clinical changes resulted in improved facial symmetry and a satisfactory functional occlusion. © 2016 American Association of Orthodontists.

Kawata T.,Kanagawa Dental University
Biomedical Research (India) | Year: 2015

The effects of long-term, artificially created, hypofunctional occlusion and its recovery on the morphology of the first molar root in mice have been investigated. C57BL/6J (Jackson Laboratory, Bar Harbor ME, USA) mice were randomly divided according to their periodontal conditions into normal, hypofunctional, and recovery groups (n = 4). In the experimental hypofunctional and recovery groups, a bite-raising appliance was set to produce hypofunction at the molar region. All groups were analyzed at 16 weeks of age using a light microscope. Root length, width, and area as well as the thickness and the area of the periodontal ligament (PDL) space of the maxillary first molar were calculated. Roots were longer and narrower in the hypofunctional group than in the control group. The mesial root in particular was markedly affected. Root area was significantly smaller in the hypofunctional group than in the other groups. PDL thickness and area were also significantly less in the hypofunctional group than in the control group, but were greater in the recovery group than in the hypofunctional group. These results suggest that root size and the PDL structure may be reduced by disuse atrophy resulting from a defect in occlusal function, but may be recovered following the gain of occlusal stimuli. © 2015, Scientific Publishers of India. All rights reserved.

The aim of the present study was to determine whether occlusal hypofunction and its recovery affected the structure of the Periodontal Ligament (PDL) and expression of Vascular Endothelial Growth Factor (VEGF) in mice. Five-week-old C57BL/6J mice (Jackson Laboratory, Bar Harbor ME, USA) were used and randomly divided into three groups: a Hypofunctional Group (HG), Recovery Group (RG), and Control Group (CG). In HG and RG, appliances were attached to the maxillary and mandibular incisors. These appliances were set for 11 weeks in HG and 7 weeks in RG. Appliances were then removed offer 0, 7, 14, and 28 days. Untreated mice served as CG. Histological sections were prepared and immunohistochemically stained for VEGF. The PDL area and the number of VEGF immunopositive cells in the PDL were evaluated in the 3 groups. The number of VEGF immunopositive cells and PDL area were significantly larger in CG white the RG than in HG, while the PDL area in RG was similar to that in CG. In the recovery process, the PDL area and number of VEGF positive cells in the PDL increased from days 0 to 7 and decreased from days 7 to 28. The results of the present study suggest that occlusal stimuli regulate the PDL area through the expression of VEGF in the mouse PDL. The clinical relevance of occlusal stimuli is their ability to regulate the expression of VEGF in PDL cells and these growth factors may lead to alveolar bone remodeling in the PDL. © 2016, Scientific Publishers of India. All rights reserved.

Kato Y.,Ohu University | Ozawa S.,Kanagawa Dental University | Miyamoto C.,Kanagawa Dental University | Maehata Y.,Kanagawa Dental University | And 3 more authors.
Cancer Cell International | Year: 2013

Acidic extracellular pH is a major feature of tumor tissue, extracellular acidification being primarily considered to be due to lactate secretion from anaerobic glycolysis. Clinicopathological evidence shows that transporters and pumps contribute to H+ secretion, such as the Na+/H+ exchanger, the H+-lactate co-transporter, monocarboxylate transporters, and the proton pump (H+-ATPase); these may also be associated with tumor metastasis. An acidic extracellular pH not only activates secreted lysosomal enzymes that have an optimal pH in the acidic range, but induces the expression of certain genes of pro-metastatic factors through an intracellular signaling cascade that is different from hypoxia. In addition to lactate, CO2 from the pentose phosphate pathway is an alternative source of acidity, showing that hypoxia and extracellular acidity are, while being independent from each other, deeply associated with the cellular microenvironment. In this article, the importance of an acidic extracellular pH as a microenvironmental factor participating in tumor progression is reviewed. © 2013 Kato et al.; licensee BioMed Central Ltd.

Nihei T.,Kanagawa Dental University
Journal of Oral Science | Year: 2016

Silane coupling agents alter the properties of material surfaces, which are modified by means of an organic functional group of specific silanes. This review describes the use of hydrophobic silane compounds for surface modification of silica-based and other materials. © 2016, Nihon University, School of Dentistry. All rights reserved.

Fujibayashi T.,Kanagawa Dental University
Japanese Journal of Clinical Radiology | Year: 2014

There are three major criteria for diagnosing Sjögren's syndrome today ; these are Japanese revised criteria (JPN) (1999), AECG criteria (2002), and ACR criteria (2012). JPN has been most commonly used in Japan including 4 diagnostic items with high diagnostic accuracy to Japanese patients. AECG criteria includes 6 items based on European criteria (1993) and had been most internationally used. ACR criteria was proposed by SICCA group in 2012, which is composed of 3 items of histopathology, ocular staining and serology. Comparison of these three criteria including diagnostic accuracy, diagnostic examination items, differences in histopathology especially in detail definition of focus are described.

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