コンメン ヒフクジュツ ニツイテ

Localized gingival recession and root exposure may cause an esthetic problem, root dentin hypersensitivity, root caries, and difficulties in plaque control. To solve the problems, root coverage procedures have been developed since 1950s. These surgical procedures are classified as pedicle soft tissue graft procedures, free soft tissue graft procedures, and regenerative procedures. Pedicle soft tissue graft procedures include the laterally repositioned flap procedure, the double papilla flap, the oblique rotational flap, the coronally advanced flap procedure, and a semi-lunar coronally repositioned flap procedure. Free soft tissue graft procedures contain the free gingival graft and the connective tissue graft. Regenerative procedures are the modifications of coronally advanced flap utilizing barrier membranes or enamel matrix derivatives. Histological observations of the human root surface treated with soft tissue graft showed that new connective tissue attachment was formed in some areas, and epithelial attachment was found in other areas. Based on the literatures, the connective tissue graft results in superior root coverage comparing with other procedures. Similarly, complete root coverage was expected in highest predictability in the connective tissue graft, especially in class I or II recession defects. The color match of the grafted area to the adjacent gingiva is esthetically more favorable with the connective tissue graft than that of a free gingival graft. However, only partial coverage may be expected in class III or IV recession defects

Time to revise COPD treatment algorithm

Parallel approach; Treatable traits; ICSEnfoque paralelo; Rasgos tratables; ICSEnfocament paral·lel; Trets tractables; ICSIn 2017, a new two-step algorithm for the treatment of COPD was proposed. This algorithm was based on the severity of symptoms and phenotypes or treatable traits, and patient-specialised assessment targeting eosinophilic inflammation, chronic bronchitis, and frequent infections is recommended after exacerbation occurs despite maximal bronchodilation therapy. However, recent studies have revealed the clinical characteristics of patients who should have second controllers added, such as ICS. We again realized that treatable traits should be assessed and intervened for as early as possible. Moreover, the treatment algorithm is necessary to be adapted to the situation of clinical practice, taking into account the characteristics of the patients. The time to revise COPD treatment algorithm has come and we propose a new 3-step parallel approach for initial COPD treatment. After the diagnosis of COPD, the first assessment is to divide into two categories based on the usual clinical characteristics for patients with COPD and the specific clinical characteristics for each patient with concomitant disease. In the former, the assessment should be based on the level of dyspnea and the frequency of exacerbations. After the assessment, mono- or dual bronchodilator should be selected. In the latter, the assessment should be based on asthma characteristics, chronic bronchitis, and chronic heart failure. After the assessment, patients with asthmatic characteristics may consider treatment with ICS, while patients with chronic bronchitis may consider treatment with roflumilast and/or macrolide, while patients with chronic heart failure may consider treatment with selective β1-blocker. The 3-step parallel approach is completed by adding an additional therapy for patients with concomitant disease to essential therapy for patients with COPD. In addition, it is important to review the response around 4 weeks after the initial therapy. This COPD management proposal might be considered as an approach based on patients’ clinical characteristics and on personalized therapy

Electronic state analysis of Li2RuO3 positive electrode for lithium ion secondary battery

An investigation was made on the electronic structure of 4d transition metal layered oxide material of Li2RuO3 using X-ray photoelectron spectroscopy (XPS) and X-ray absorption spectroscopy (XAS). The intensity of O K pre-edge peak increased for Li ion extracted samples, suggesting increased ligand holes. The Ru 3d XPS spectrum suggested the variation of local structure around Ru ions by extraction of Li ions. We conclude that the delithiation from Li2RuO3 is charge-compensated by O anions, and that the creation of the ligand holes reorganizes electronic structures composed of highly hybridized Ru 4d and O 2p orbitals

Adaptive Cation Pillar Effects Achieving High Capacity in Li-Rich Layered Oxide, Li₂MnO₃-LiMeO₂ (Me = Ni, Co, Mn)

リチウムイオン電池正極の低結晶層状構造を支える2種類の支柱. 京都大学プレスリリース. 2022-09-05.Intensive research is underway to further enhance the performance of lithium-ion batteries (LIBs). To increase the capacity of positive electrode materials, Li-rich layered oxides (LLO) are attracting attention but have not yet been put to practical use. The structural mechanisms through which LLO materials exhibit higher capacity than conventional materials remain unclear because their disordered phases make it difficult to obtain structural information by conventional analysis. The X-ray total scattering analysis reveals a disordered structure consisting of metal ions in octahedral and tetrahedral sites of Li layers as a result of cation mixing after the extraction of Li ions. Metal ions in octahedral sites act as rigid pillars. The metal ions move to the tetrahedral site of the Li layer, which functions as a Li-layer pillar during Li extraction, and returns to the metal site during Li insertion, facilitating Li diffusion as an adaptive pillar. Adaptive pillars are the specific structural features that differ from those of the conventional layered materials, and their effects are responsible for the high capacity of LLO materials. An essential understanding of the pillar effects will contribute to design guidelines for intercalation-type positive electrodes for next-generation LIBs

Disordered Cubic Spinel Structure in the Delithiated Li2MnO3 Revealed by Difference Pair Distribution Function Analysis

An archetypical Li-rich layered oxide, Li2MnO3, shows a large initial charge capacity of ~350 mAh g-1 with little oxidation of the constituent Mn ions, yet, the crystal structure of delithiated Li2MnO3 is still unclarified because the structural disorder induced by the considerable Li extraction makes the analysis challenging. X-ray pair distribution function (PDF) analysis is a powerful tool to experimentally elucidate the structure of the disordered phase. Here, we conducted a comprehensive analysis with a focus on PDF analysis in combination with the X-ray powder diffraction (XRPD), transmission electron microscopy (TEM), and X-ray absorption spectroscopy (XAS) to reveal the disordered crystalline structure of the electrochemically delithiated Li2MnO3. The XRPD and TEM analyses clarified the formation of a low-crystallinity phase in the light of the average structure. The XAS and PDF analyses further revealed that the MnO6–based framework was rearranged with maintaining the MnO6 octahedral coordination after the initial charge. The difference pair distribution function (d-PDF) technique was therefore employed to extract the structural information of the low-crystallinity disordered phase. The delithiated phase was found to have a structure similar to the cubic spinel, LiMn2O4, rather than that of delithiated LiMn2O4 (λ-MnO2). In addition, the middle-range order of the delithiated phase deteriorated after the charge, indicating a decrease of coherent domain size to a single nm order. The composite structure formed after the first charge, therefore, consists of the disordered cubic spinel structure and unreacted Li2MnO3. The formation of the composite structure “activates” the electrode material structurally and eventually induces characteristic large capacity of this material

Adaptive Cation Pillar Effects Achieving High Capacity in Li-Rich Layered Oxide, Li2MnO3-LiMeO2 (Me = Ni, Co, Mn)

Intensive research is underway to further enhance the performance of lithium-ion batteries (LIBs). To increase the capacity of positive electrode materials, Li-rich layered oxides (LLO) are attracting attention but have not yet been put to practical use. The structural mechanisms through which LLO materials exhibit higher capacity than conventional materials remain unclear because their disordered phases make it difficult to obtain structural information by conventional analysis. The X-ray total scattering analysis reveals a disordered structure consisting of metal ions in octahedral and tetrahedral sites of Li layers as a result of cation mixing after the extraction of Li ions. Metal ions in octahedral sites act as rigid pillars. The metal ions move to the tetrahedral site of the Li layer, which functions as a Li-layer pillar during Li extraction, and returns to the metal site during Li insertion, facilitating Li diffusion as an adaptive pillar. Adaptive pillars are the specific structural features that differ from those of the conventional layered materials, and their effects are responsible for the high capacity of LLO materials. An essential understanding of the pillar effects will contribute to design guidelines for intercalation-type positive electrodes for next-generation LIBs

ヒロシマ ダイガク シガクブ リンショウ ジッシュウ シサツ ホウコク

We made a field trip to Hiroshima University Hospital to observe its clinical training practices on February 22, 2013. Distinctive features of the clinical training system were as follows. 1) Training schedule. Learning objectives and clinical cases required are established in each specialty clinics. Students can make training schedules in each specialty clinic for themselves in accordance with the progress of required cases of their own. They can move from a clinic to other clinic in a day in order to follow their cases. 2) The small group system and the tutor system for the group. Students are assigned to a group consisting of 3 to 4 persons. They get a clinical training together and share clinical experiences with each other. They hold the group meeting every other Wednesday. The tutor checks the progress on their cases and discusses about next training objectives with each person. 3) The stepwise training and evaluation system. The clinical training are given in 3 terms. Learning objectives in each term are established in stepwise setting. Students are evaluated for their levels of attainment at the end of each term. 4) Morning meeting and mini-lecture. Students attend morning meeting and a mini-lecture before the clinical training everyday. 5) Clinical clerkship. Clinical clerkship has been performed with support of patients. Patients in the hospital are informed for the clinical clerkship. Participants provide written informed consent prior to entry into the system. However, the number of patients for clinical clerkship were not enough. These features are informative and helpful for us to improve our clinical training system. And recruitment of patients who kindly support the clinical clerkship may be the biggest problem to solve in both universities

Direct observation of reversible oxygen anion redox reaction in Li-rich manganese oxide, Li2MnO3, studied by soft X-ray absorption spectroscopy

Li-rich layered oxides have attracted attention as promising positive electrode materials for next-generation lithium-ion secondary batteries because of their high energy storage capacity. The participation of the oxygen anion has been hypothesized to contribute to these oxides' high capacity. In the present study, we used O K-edge and Mn L-edge X-ray absorption spectroscopy (XAS) to study the reversible redox reactions that occur in single-phase Li-rich layered manganese oxide, Li2MnO3. We semiquantitatively analyzed the oxygen and manganese reactions by dividing the charge/discharge voltage region into two parts. The O K-edge XAS indicated that the electrons at the oxygen site reversibly contributed to the charge compensation throughout the charge/discharge processes at operating voltages between 2.0 and 4.8 V vs. Li+/Li0. The Mn L-edge XAS spectra indicated that the Mn redox reaction occurred only in the lower-voltage region. Thus, at higher potentials, the electrons, mainly at the oxygen site, contributed to the charge compensation. Peaks whose energies were similar to peroxide appeared in and then disappeared from the O K-edge spectra obtained during the reversible redox cycles. These results indicate that the reorganization of the oxygen network in the crystal structure affects the redox components. By using two kinds of detection modes with different probing depths in XAS measurements, it was found that these redox reactions are bulk phenomena in the electrode

The Aggregation Inhibitor Peptide QBP1 as a Therapeutic Molecule for the Polyglutamine Neurodegenerative Diseases

Misfolding and abnormal aggregation of proteins in the brain are implicated in the pathogenesis of various neurodegenerative diseases including Alzheimer's, Parkinson's, and the polyglutamine (polyQ) diseases. In the polyQ diseases, an abnormally expanded polyQ stretch triggers misfolding and aggregation of the disease-causing proteins, eventually resulting in neurodegeneration. In this paper, we introduce our therapeutic strategy against the polyQ diseases using polyQ binding peptide 1 (QBP1), a peptide that we identified by phage display screening. We showed that QBP1 specifically binds to the expanded polyQ stretch and inhibits its misfolding and aggregation, resulting in suppression of neurodegeneration in cell culture and animal models of the polyQ diseases. We further demonstrated the potential of protein transduction domains (PTDs) for in vivo delivery of QBP1. We hope that in the near future, chemical analogues of aggregation inhibitor peptides including QBP1 will be developed against protein misfolding-associated neurodegenerative diseases