Publications by authors named "Kei Wada"

Nd:YAG laser is in common clinical use for the treatment of tissue incision, transpiration, and haemostasis in soft tissues. However, few studies have reported the effects of low-level laser therapy (LLLT) from Nd:YAG laser on bone healing. The aim of this study was to perform three-dimensional (3D) morphological evaluation of the photobiomodulation of Nd:YAG laser in bone defects in rat tibiae using micro-computed tomography CT (micro-CT) imaging.

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Article Synopsis
  • Heterosigma akashiwo virus (HaV) is a dsDNA virus that infects the raphidoflagellate Heterosigma akashiwo, with both exhibiting diverse infection characteristics.* -
  • The study involved cross-infectivity tests with 60 H. akashiwo and 22 HaV strains to explore their infection specificity and lysis rates.* -
  • Results indicated that not all host-virus combinations led to algal lysis, and variations in viral concentration suggested differences in infection efficiency among strains.*
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The Acetaminophen Detection Kit® (Kanto Chemical Company Co. Inc., Tokyo, Japan) is a colorimetric test based on an indophenol reaction.

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PcyA, a ferredoxin-dependent bilin pigment reductase, catalyzes the site-specific reduction of the two vinyl groups of biliverdin (BV), producing phycocyanobilin. Previous neutron crystallography detected both the neutral BV and its protonated form (BVH) in the wildtype (WT) PcyA-BV complex, and a nearby catalytic residue Asp105 was found to have two conformations (protonated and deprotonated). Semiempirical calculations have suggested that the protonation states of BV are reflected in the absorption spectrum of the WT PcyA-BV complex.

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Heterocapsa circularisquama RNA virus (HcRNAV) is the only dinoflagellate-infecting RNA virus that has been isolated to date. We herein investigated the diversity of the major capsid protein gene of HcRNAV and related viruses using degenerate PCR and in silico ana-lyses. Diverse sequences related to HcRNAV were successfully amplified from marine sediments.

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Background/aim: The aim of this study was to evaluate the effect of low-intensity pulsed ultrasound (LIPUS) on bone metabolism during the healing period in rat tibiae bone defects using micro-computed tomography (micro CT) imaging for three-dimensional morphological evaluation.

Materials And Methods: The right tibia received ultrasound exposure (US group) every day, whereas the opposite side served as a control (Control group). At 1, 2, and 3 weeks after the operation, micro CT was performed, and the volume and surface area of new bone formation in the bone defects was evaluated three-dimensionally.

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Cyanobacteriochromes (CBCRs) are bilin-binding photosensors of the phytochrome superfamily that show remarkable spectral diversity. The green/red CBCR subfamily is important for regulating chromatic acclimation of photosynthetic antenna in cyanobacteria and is applied for optogenetic control of gene expression in synthetic biology. It is suggested that the absorption change of this subfamily is caused by the bilin C15/C15- photoisomerization and a subsequent change in the bilin protonation state.

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Hydroxymethylbilane synthase (HMBS), which is involved in the heme biosynthesis pathway, has a dipyrromethane cofactor and combines four porphobilinogen (PBG) molecules to form a linear tetrapyrrole, hydroxymethylbilane. Enzyme kinetic study of human HMBS using a PBG-derivative, 2-iodoporphobilinogen (2-I-PBG), exhibited noncompetitive inhibition with the inhibition constant being 5.4 ± 0.

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A bivalve-killing marine dinoflagellate, Heterocapsa circularisquama, is susceptible to the infectious single-stranded RNA virus, Heterocapsa circularisquama RNA virus (HcRNAV). The ecological relationship between H. circularisquama and HcRNAV was intensively studied from 2001 through 2005; however, only limited data are available for the ecological dynamics of HcRNAV before 2001.

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IscU is a central component of the ISC machinery and serves as a scaffold for de novo assembly of Fe-S clusters. The dedicated chaperone system composed of the Hsp70-chaperone HscA and the J-protein cochaperone HscB synergistically interacts with IscU and facilitates cluster transfer from IscU to recipient apo-proteins. Here, we report that the otherwise essential roles of HscA and HscB can be bypassed in vivo by a number of single amino acid substitutions in IscU.

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Purpose: The purpose of this retrospective computed tomography study was to evaluate bone availability for dental implant placement, frequency of bone augmentation procedures, frequency of anatomical structures that compromise implant placement, and frequency of implant dimensions, and to determine which edentulous sites would benefit from the use of a sloped implant versus a traditional flat design.

Materials And Methods: Recorded parameters included the width of the ridge, the buccal and lingual/palatal alveolar bone height in reference to different anatomical landmarks, determination of implant placement, selection of an implant with a flat or sloped top, and need for a secondary bone augmentation procedure.

Results: One thousand three hundred seventy edentulous sites were evaluated in 216 patients.

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Arterial thrombus formation is thought to be initiated by platelet adhesion to the subendothelial matrix, but ruptured atherosclerotic plaques are characterized by substantial reduction of matrix proteins compared with stable plaques. Intraplaque erythrocytes and/or fibrin have been reported in high-risk coronary plaques. The aims of the current study were to identify factors that provide scaffolds for platelets at the sites of ruptured coronary plaques and investigate depositions of iron and bilirubin as hemoglobin catabolites in the ruptured plaques.

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Phytochromobilin (PΦB) is a red/far-red light sensory pigment in plant phytochrome. PΦB synthase is a ferredoxin-dependent bilin reductase (FDBR) that catalyzes the site-specific reduction of bilins, which are sensory and photosynthesis pigments, and produces PΦB from biliverdin, a heme-derived linear tetrapyrrole pigment. Here, we determined the crystal structure of tomato PΦB synthase in complex with biliverdin at 1.

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ChlR is a MarR-type transcriptional regulator that activates the transcription of the operon in response to low oxygen conditions in the cyanobacterium sp. PCC 6803. Upon exposure to low oxygen conditions, ChlR activates transcription of the operon that encodes enzymes critical to tetrapyrrole biosynthesis under low oxygen conditions.

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IscU is a central component of the ISC machinery and serves as a scaffold for the de novo assembly of iron-sulfur (Fe-S) clusters prior to their delivery to target apo-Fe-S proteins. However, the molecular mechanism is not yet fully understood. In this study, we have conducted mutational analysis of E.

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In mammals, the green heme metabolite biliverdin is converted to a yellow anti-oxidant by NAD(P)H-dependent biliverdin reductase (BVR), whereas in O-dependent photosynthetic organisms it is converted to photosynthetic or light-sensing pigments by ferredoxin-dependent bilin reductases (FDBRs). In NADP-bound and biliverdin-bound BVR-A, two biliverdins are stacked at the binding cleft; one is positioned to accept hydride from NADPH, and the other appears to donate a proton to the first biliverdin through a neighboring arginine residue. During the FDBR-catalyzed reaction, electrons and protons are supplied to bilins from ferredoxin and from FDBRs and waters bound within FDBRs, respectively.

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Heme oxygenase-1 (HMOX1) catalyzes heme degradation utilizing reducing equivalents supplied from NADPH-cytochrome P450 reductase (CYPOR). Recently, we determined the complex structure of NADP -bound open-conformation stabilized CYPOR and heme-HMOX1, but the resolution was limited to 4.3 Å.

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In mammals, catabolism of the heme group is indispensable for life. Heme is first cleaved by the enzyme Heme Oxygenase (HO) to the linear tetrapyrrole Biliverdin IXα (BV), and BV is then converted into bilirubin by Biliverdin Reductase (BVR). HO utilizes three Oxygen molecules (O2) and seven electrons supplied by NADPH-cytochrome P450 oxidoreductase (CPR) to open the heme ring and BVR reduces BV through the use of NAD(P)H.

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The objective of this study was to evaluate the effectiveness of precise three-dimensional hydroxyapatite printed micro- and macrochannel devices for alveolar ridge augmentation in a canine model. All grafts induced minimal inflammatory and fibrotic reactions. Examination of undecalcified sections revealed that both types of grafts demonstrated bone ingrowth.

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2-Amino-4-{[3-(carboxymethyl)phenoxy](methoxy)phosphoryl}butanoic acid (GGsTop) is a potent, highly selective, nontoxic, and irreversible inhibitor of γ-glutamyl transpeptidase (GGT). GGsTop has been widely used in academic and medicinal research, and also as an active ingredient (Nahlsgen) in commercial anti-aging cosmetics. GGsTop consists of four stereoisomers due to the presence of two stereogenic centers, i.

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Biogenesis of iron-sulfur (Fe-S) clusters is an indispensable process in living cells. In Escherichia coli, the SUF biosynthetic system consists of six proteins among which SufB, SufC and SufD form the SufBCD complex, which serves as a scaffold for the assembly of nascent Fe-S cluster. Despite recent progress in biochemical and structural studies, little is known about the specific regions providing the scaffold.

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Telomeric repeat-containing RNA is a new noncoding RNA molecule that performs various biofunctions. Heterogeneous nuclear ribonucleoprotein (hnRNP) A1 is an RNA-binding protein involved in the telomere maintenance machinery. To date, little is known about how hnRNPA1 binds to telomeric RNA.

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Biliverdin reductase catalyses the last step in haem degradation and produces the major lipophilic antioxidant bilirubin via reduction of biliverdin, using NAD(P)H as a cofactor. Despite the importance of biliverdin reductase in maintaining the redox balance, the molecular details of the reaction it catalyses remain unknown. Here we present the crystal structure of biliverdin reductase in complex with biliverdin and NADP.

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Phycocyanobilin:ferredoxin oxidoreductase (PcyA) catalyzes the reduction of biliverdin (BV) to produce phycocyanobilin, a linear tetrapyrrole pigment used for light harvesting and light sensing. Spectroscopic and HPLC analyses inidicate that BV bound to the I86D mutant of PcyA is fully protonated (BVH ) and can accept an electron, but I86D is unable to donate protons for the reduction; therefore, compared to the wild-type PcyA, the I86D mutant stabilizes BVH . To elucidate the structural basis of the I86D mutation, we determined the atomic-resolution structure of the I86D-BVH complex and the protonation states of the essential residues Asp105 and Glu76 in PcyA.

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