ガクガンメン リョウイキ ニオケル コツチユ ニ タイスル テイシュツリョク チョウオンパ パルス ショウシャ ノ シヨウ ケイケン

Fracture healing has traditionally been thought to be a naturally optimized process with predetermined time-course for bone metabolism, and no one had had an idea that fracture healing may be manipulated to occur at a faster rate. In 1980s, the use of low-intensity pulsed ultrasound (LIPUS) was demonstrated with a significant promotion of bone healing and LIPUS has been used extensively for bone fractures in the limbs. On the other hand, the effectiveness of LIPUS for maxillofacial bone fractures has not been studied yet. In clinical orthodontics, there are many cases closely related to bone healing: the traumatic bone fracture in maxillofacial region, the osteotomy of jaw deformity, and the bone grafting in to alveolar cleft. The purpose of this study was to examine the benefit of LIPUS to the acceleration of maxillofacial bone healing. Thirty-five patients received LIPUS after surgery served as subjects. Of total subjects, 11 patients had surgery for maxillofacial bone fracture fixation, 7 patients with jaw deformity had orthognathic surgery, and 17 patients affected by cleft lip and palate underwent alveolar cleft bone grafting. Five-seven days after surgery, the patient received 15 minutes of LIPUS (BR sonic-pro, ITO Co., Tokyo, Japan) per day for 14 days. A LIPUS signal was transmitted at a frequency of 1.0 MHz with a spatial-average intensity of 160 mW and pulsed 1: 4. In addition, we used the visual analogue scale (VAS) for pain assessment, and simple radiographs and computed tomography (CT) for evaluation of the bone healing. In most cases, pain disappeared within one week after surgery. In the patients with bone fracture fixation or jaw osteotomy, bone healing was validated by plain radiographs and/or CT taken at 3 months after surgery, leading to stable occlusion. In the cases with alveolar bone grafting, early bone formation was observed from CT taken at 3 months after surgery. In addition, the catabolic effects of LIPUS exposure were not found at all. In conclusion, LIPUS application might involve in acceleration of maxillofacial bone healing after surgery. Therefore, LIPUS may be a promising therapeutic tool for bone healing in maxillofacial region

Molecular Landscape of the Ribosome Pre-initiation Complex during mRNA Scanning: Structural Role for eIF3c and Its Control by eIF5

Citation: Obayashi, E., Luna, R. E., Nagata, T., Martin-Marcos, P., Hiraishi, H., Singh, C. R., . . . Asano, K. (2017). Molecular Landscape of the Ribosome Pre-initiation Complex during mRNA Scanning: Structural Role for eIF3c and Its Control by eIF5. Cell Reports, 18(11), 2651-2663. doi:10.1016/j.celrep.2017.02.052During eukaryotic translation initiation, eIF3 binds the solvent-accessible side of the 40S ribosome and recruits the gate-keeper protein eIF1 and eIF5 to the decoding center. This is largely mediated by the N-terminal domain (NTD) of eIF3c, which can be divided into three parts: 3c0, 3c1, and 3c2. The N-terminal part, 3c0, binds eIF5 strongly but only weakly to the ribosome-binding surface of eIF1, whereas 3c1 and 3c2 form a stoichiometric complex with eIF1. 3c1 contacts eIF1 through Arg-53 and Leu-96, while 3c2 faces 40S protein uS15/S13, to anchor eIF1 to the scanning pre-initiation complex (PIC). We propose that the 3c0:eIF1 interaction diminishes eIF1 binding to the 40S, whereas 3c0:eIF5 interaction stabilizes the scanning PIC by precluding this inhibitory interaction. Upon start codon recognition, interactions involving eIF5, and ultimately 3c0:eIF1 association, facilitate eIF1 release. Our results reveal intricate molecular interactions within the PIC, programmed for rapid scanning-arrest at the start codon

The 2G allele of promoter region of Matrix metalloproteinase-1 as an essential pre-condition for the early onset of oral squamous cell carcinoma

<p>Abstract</p> <p>Background</p> <p>Matrix metalloproteinase (<it>MMP</it>) is known to be involved in the initial and progressive stages of cancer development, and in the aggressive phenotypes of cancer. This study examines the association of single nucleotide polymorphisms in promoter regions of <it>MMP-1 </it>and <it>MMP-3 </it>with susceptibility to oral squamous cell carcinoma (OSCC).</p> <p>Methods</p> <p>We compared 170 Japanese OSCC cases and 164 healthy controls for genotypes of <it>MMP-1 </it>and <it>MMP-3</it>.</p> <p>Results</p> <p>The frequency of the <it>MMP-1 </it>2G allele was higher and that of the 1G homozygote was lower in the OSCC cases (<it>p </it>= 0.034). A multivariate logistic regression analysis revealed that subjects who were 45 years old or older had a significantly increased (2.47-fold) risk of OSCC (95%CI 1.47–4.14, <it>p </it>= 0.0006), and those carrying the <it>MMP-1 </it>2G allele had a 2.30-fold risk (95%CI 1.15–4.58, <it>p </it>= 0.018), indicating independent involvement of these factors in OSCC. One of the key discoveries of this research is the apparent reduction of the <it>MMP-1 </it>1G/1G and 1G/2G genotype distributions among the early onset OSCC cases under the ages of 45 years. It should be noted that the tongue was the primary site in 86.2% of these early onset cases. This could suggest the specific carcinogenic mechanisms, i.e. specific carcinogenic stimulations and/or genetic factors in the tongue.</p> <p>Conclusion</p> <p>Since the 2G allele is a majority of the <it>MMP-1 </it>genotype in the general population, it seems to act as a genetic pre-condition in OSCC development. However this report suggests a crucial impact of the <it>MMP-1 </it>2G allele in the early onset OSCC.</p

Analgesia mediated by the TRPM8 cold receptor in chronic neuropathic pain

SummaryBackgroundChronic established pain, especially that following nerve injury, is difficult to treat and represents a largely unmet therapeutic need. New insights are urgently required, and we reasoned that endogenous processes such as cooling-induced analgesia may point the way to novel strategies for intervention. Molecular receptors for cooling have been identified in sensory nerves, and we demonstrate here how activation of one of these, TRPM8, produces profound, mechanistically novel analgesia in chronic pain states.ResultsWe show that activation of TRPM8 in a subpopulation of sensory afferents (by either cutaneous or intrathecal application of specific pharmacological agents or by modest cooling) elicits analgesia in neuropathic and other chronic pain models in rats, thereby inhibiting the characteristic sensitization of dorsal-horn neurons and behavioral-reflex facilitation. TRPM8 expression was increased in a subset of sensory neurons after nerve injury. The essential role of TRPM8 in suppression of sensitized pain responses was corroborated by specific knockdown of its expression after intrathecal application of an antisense oligonucleotide. We further show that the analgesic effect of TRPM8 activation is centrally mediated and relies on Group II/III metabotropic glutamate receptors (mGluRs), but not opioid receptors. We propose a scheme in which Group II/III mGluRs would respond to glutamate released from TRPM8-containing afferents to exert an inhibitory gate control over nociceptive inputs.ConclusionsTRPM8 and its central downstream mediators, as elements of endogenous-cooling-induced analgesia, represent a novel analgesic axis that can be exploited in chronic sensitized pain states

Expression of Transient Receptor Potential Ankyrin 1 (TRPA1) and Its Role in Insulin Release from Rat Pancreatic Beta Cells

<div><h3>Objective</h3><p>Several transient receptor potential (TRP) channels are expressed in pancreatic beta cells and have been proposed to be involved in insulin secretion. However, the endogenous ligands for these channels are far from clear. Here, we demonstrate the expression of the transient receptor potential ankyrin 1 (TRPA1) ion channel in the pancreatic beta cells and its role in insulin release. TRPA1 is an attractive candidate for inducing insulin release because it is calcium permeable and is activated by molecules that are produced during oxidative glycolysis.</p> <h3>Methods</h3><p>Immunohistochemistry, RT-PCR, and Western blot techniques were used to determine the expression of TRPA1 channel. Ca²⁺ fluorescence imaging and electrophysiology (voltage- and current-clamp) techniques were used to study the channel properties. TRPA1-mediated insulin release was determined using ELISA.</p> <h3>Results</h3><p>TRPA1 is abundantly expressed in a rat pancreatic beta cell line and freshly isolated rat pancreatic beta cells, but not in pancreatic alpha cells. Activation of TRPA1 by allyl isothiocyanate (AITC), hydrogen peroxide (H₂O₂), 4-hydroxynonenal (4-HNE), and cyclopentenone prostaglandins (PGJ₂) and a novel agonist methylglyoxal (MG) induces membrane current, depolarization, and Ca²⁺ influx leading to generation of action potentials in a pancreatic beta cell line and primary cultured pancreatic beta cells. Activation of TRPA1 by agonists stimulates insulin release in pancreatic beta cells that can be inhibited by TRPA1 antagonists such as HC030031 or AP-18 and by RNA interference. TRPA1-mediated insulin release is also observed in conditions of voltage-gated Na⁺ and Ca²⁺ channel blockade as well as ATP sensitive potassium (K_ATP) channel activation.</p> <h3>Conclusions</h3><p>We propose that endogenous and exogenous ligands of TRPA1 cause Ca²⁺ influx and induce basal insulin release and that TRPA1-mediated depolarization acts synergistically with K_ATP channel blockade to facilitate insulin release.</p> </div

Analysis of free radical reaction in a sample irradiated by heaby-ion beam

The oxygen effect is severe problem in radiation therapies for hypoxic tumors using low linear energy transfer (LET) irradiation, such as X-ray and gamma-ray. Recent researches showed a fact that the around 2-fold oxygen effect was also obtained using high LET irradiation, such as heavy-ion beams. Although the carbon ion beam has been utilized to cancer therapy in Japan from 1994, detail mechanisms of interactions between the heavy ion beams and the biological systems were still in progress. When living tissue was irradiated by low LET irradiation, the redox status in the tissue can be changed due to several reactive species occurred in the cell during and after the irradiation. The oxygen consumption in the tissue may be changed by the damaging cells and/or its recovery process. The change of oxygen consumption also can affect to the redox status in the tissue. Since the oxygen effect has been considered as that is caused by free radical reactions of initial reactive species caused by ionization of water with oxygen to provide several reactive oxygen species (ROS), detection of free radical reactions in the sample irradiated by heavy-ion beams is important to understand the oxygen effect of high LET irradiation. Nitroxyl radicals are oxidized to the corresponding oxoammonium cation by ROS, such as hydroxyl radical and/or superoxide, which are generated directly by ionization of water and/or indirectly by sequential oxygen-mediated reactions. The oxoammonium cation can be reduced to the corresponding hydroxylamine by obtaining a hydrogen atom from hydrogen donor, such as GSH, HADH, and/or NADPH. When beta-ray, X-ray or gamma-ray is irradiated to a solution including TEMPOL and glutathione (GSH), the EPR signal intensity of the TEMPOL is decreased depending on the radiation doses. The reduction of TEMPOL does not occur without GSH. In this paper, detection of free radical reactions in a sample irradiated by a heavy-ion beam was tested. 10 g of gelatin was dissolved into 100 mL of 100 mM PBS (pH7) including 0.05 mM DTPA at 80degC. Another 200 mL of the PBS buffer (room temperature) was added to that hot gelatin solution. The gelatin solution was cool down to room temperature. Then, TEMPOL and GSH were added into the gelatin solution to make those concentrations 0.1 mM and 1 mM, respectively. This reaction mixture with gelatin was transferred into a 8.3 x 12.0 x 4.2 cm plastic container and fixed in a refrigerator for 2 hr. After the gelatin was fixed, the one side wall of the plastic container was opened. 290 MeV carbon beam was irradiated with parameters below; thickness of binary filter was 100 mm (Bragg peak will be 5 cm depth), size of collimator window was 1 x 1 cm, dose at surface was 16 Gy (5.99 x 10-5 Gy/count x 269898 count), and irradiation time was 127.3 s. The gelatin was sampled using glass capillary from several locations on and off the beam track after the irradiation. The gelatin sample was measured by X-band EPR.The EPR signals of TEMPOL in the samples from surface to Bragg peak on the beam track decreased compared with other locations. The EPR signal at the location 1 cm deeper from Bragg peak, however, decreased much lesser. The EPR signal at 2.5 cm deeper of Bragg peak showed almost no decreasing. The EPR signals from location off the beam track also showed almost no decreasing. Decreasing of EPR signal occurred continuously after irradiation. Extrapolated value of signal intensity to time 0 min from end of irradiation was almost the same for all locations. The free radical reactions may occurred in the sample after irradiation of heavy-ion beam within a very limited volume, where was from surface to Bragg peak on the beam track.A Joint Conference of the 12th In Vivo EPR Spectroscopy and Imaging and the 9th International EPR Spin Trapping/Spin Labelin

Visualization of free radical reactions in an aqueous sample irradiated by 290 MeV carbon beam

The detection of free radical reactions in a gelatin sample irradiated by heavy-ion beam was tested using electron paramagnetic resonance (EPR) spectroscopic and MRI methods. Geometry and the amount of free radical eneration in a sample are described. A reaction mixture containing glutathione and a nitroxyl radical, TEMPOL, was caked with gelatin, and then irradiated with a 290 MeV carbon beam. The amount of free radical generation in a solic sample was almost flat from the surface to the beam end, except for a small peak, the peak radioactivation profile, and then steeply decrased approaching the beam end. Total free radical reactions obtained with carbon-beam irradication were expected to be less than one-third of X-ray irradiation, when the same dose for a deeper target was considered. Both EPR and MRI are useful tools to visualize free radical generation in samples irradiated by a heavy-ion beam. The EPR-based method is more sensitive and quantitative than the MRI-based method; however, the MRI method can achieve high spatial resolution. This study gives the rationale for a redox regulation trial using antioxidant drugs to reduce the side effects on normal tissues in carbon-beam therapy