Discotic liquid crystals of transition metal complexes 51(dagger): Synthesis and mesomorphism of flat-pumpkin-shaped phthalocyanine-fullerene dyads

We have synthesized a novel type of donor-acceptor liquid crystalline material, phthalocyanine-fullerene (Pc-C-60) dyad, [m,p,m'-(C14O)(3)PhO](6)PcCu-C-60 (7), and the Pc precursors, [m,p,m'-(C14O)(3)PhO](6)PcCu-OFBA (6) and [m,p,m'-(C14O)(3)PhO](6)PcCu-OH (5), and established their mesomorphism by using a polarizing optical microscope, a differential scanning calorimeter and a small angle X-ray diffractometer. Very interestingly, their corresponding previous parent Pc derivative, [m,p,m'-(C14O)(3)PhO](8)PcCu (4), shows a very wide temperature region ca. 90 degrees C of a bicontinuous Cub(Pn3m) mesophase, whereas the present children Pc precursors (5 and 6) and Pc-C-60 dyad 7 show not the Cub mesophase but a Col(ho) mesophase. It is also noteworthy that the staking distance in the Col(ho) mesophase of the Pc-C-60 dyad 7 was a very big value of ca. 9.1 angstrom, which is the biggest in discotic liquid crystals to our best knowledge. It may be originated from the biggest excluded volume caused by thermal fluctuation of peripheral long alkoxy chains at m, m'-positions. The excluded volume caused by thermal fluctuation of the peripheral long chains is so big that the molecular shape of the Pc derivative 4 and the Pc-C-60 dyad 7 very resembles a flat pumpkin.ArticleJOURNAL OF PORPHYRINS AND PHTHALOCYANINES. 18(10-11):856-868 (2014)journal articl

Dual role for alkali metal cations in enhancing the low-temperature radical polymerization of N,N-dimethylacrylamide

The radical polymerization of N,N-dimethylacrylamide (DMAAm) has been investigated in the presence of several alkali metal salts, including lithium bis(trifluoromethanesulfonyl)imide (LiNTf2). The addition of an alkali metal salt led to a significant increase in the yield and molecular weight of the resulting polymer. NMR analysis of mixtures of DMAAm and LiNTf2 suggested that DMAAm was being activated by the coordination of Li+ to its C=O group. Electron spin resonance analysis of the DMAAm polymerization in the presence of LiNTf2 suggested that the propagating radical was being stabilized by Li+ through a single-electron lithium bond, because a signal for the propagating radical of the acrylamide derivatives was observed for the first time in solution when LiNTf2 was added. Based on these results, we have proposed a mechanism for this polymerization, where the propagation steps occur between a lithium ion-stabilized propagating radical and a lithium ion-activated incoming monomer. Furthermore, polymers with a wide range of stereoregularities, such as isotactic, syndiotactic and heterotactic systems, were successfully prepared using this method by carefully selecting the appropriate combination of solvent and alkali metal salt

Syndiotactic- and heterotactic-specific radical polymerization of N-n-propylmethacrylamide complexed with alkali metal ions

We investigated the radical polymerization of N-n-propylmethacrylamide (NNPMAAm) in the presence of alkali metal bis(trifluoromethanesulfonyl)imides (MNTf2), in particular LiNTf2. The addition of MNTf2 led to a significant improvement in the yield and molecular weight of the resulting poly(NNPMAAm)s. Furthermore, the solvent employed influenced stereospecificity in the presence of LiNTf2. The stoichiometry of the NNPMAAm–Li+ complex appeared to be critical to determining the stereospecificity in the NNPMAAm polymerization. The 1:1-complexed monomer in protic polar solvents provided syndiotactic-rich polymers, whereas the 2:1-complexed monomer in aprotic solvents gave heterotactic-rich polymers. Stereochemical analyses revealed that m-addition by an r-ended radical was the key step in the induction of heterotactic specificity in the aprotic solvents. Spectroscopic analyses suggested that the Li+ cation played a dual role in the polymerization process, with Li+ stabilizing the propagating radical species and also activating the incoming monomer. Kinetic studies with the aid of electron spin resonance spectroscopy revealed that the addition of LiNTf2 caused a significant increase in the kp value and a decrease in the kt value. The stereoregularity of poly(NNPMAAm)s was found to influence the phase transition behavior of their aqueous solutions. In a series of syndiotactic-rich polymers, the phase-transition temperature decreased gradually with increase in rr triad content. Furthermore, heterotactic-rich poly(NNPMAAm) exhibited high hysteresis, which increased in magnitude with increasing mr triad content

Thermally induced cationic polymerization of isobutyl vinyl ether in toluene in the presence of solvate ionic liquid

Radical polymerization of isobutyl vinyl ether (IBVE) was attempted with the aid of the interaction between the corresponding propagating radical and lithium cation (Li+). LiN(SO2CF3)2 (LiNTf2) and ester compounds, such as methyl methacrylate (MMA) and vinyl acetate (VAc), were added as a Li+ source and dissolving agent for LiNTf2, respectively. Homopolymers of cationically polymerizable IBVE were obtained despite the presence of radically polymerizable monomers such as MMA and VAc. Contrary to our expectation, the polymerization proceeded via not a radical mechanism but a cationic mechanism. However, this cationic polymerization was found to be unusual. In particular, the polymer yield increased with the polymerization temperature; successful polymerization was observed at 100 °C, whereas no polymerization occurred at lower temperatures such as at 0 °C. The behavior of the present system was therefore defined as “thermally induced cationic polymerization”. The mechanism of thermally induced cationic polymerization is still not clear, but it is assumed that the propagating cation is markedly stabilized through its interaction with the solvate ionic liquid formed between LiNTf2 and the Lewis base

Ycf12 is a core subunit in the photosystem II complex

AbstractThe latest crystallographic model of the cyanobacterial photosystem II (PS II) core complex added one transmembrane low molecular weight (LMW) component to the previous model, suggesting the presence of an unknown transmembrane LMW component in PS II. We have investigated the polypeptide composition in highly purified intact PS II core complexes from Thermosynechococcus elongatus, the species which yielded the PS II crystallographic models described above, to identify the unknown component. Using an electrophoresis system specialized for separation of LMW hydrophobic proteins, a novel protein of ∼5 kDa was identified as a PS II component. Its N-terminal amino acid sequence was identical to that of Ycf12. The corresponding gene is known as one of the ycf (hypothetical chloroplast reading frame) genes, ycf12, and is widely conserved in chloroplast and cyanobacterial genomes. Nonetheless, the localization and function of the gene product have never been assigned. Our finding shows, for the first time, that ycf12 is actually expressed as a component of the PS II complex in the cell, revealing that a previously unidentified transmembrane protein exists in the PS II core complex

セルフアーカイブしよう! :KURA と金沢大学教員総覧

DRFIC2008 Poster Session Recap one-minute oral presentation No.3DRFIC2008 ポスターセッションまとめ 口頭プレゼンテーション資料 3

Thoracoscopic Resections of Bronchogenic Cysts Arising in the Posterior Mediastinum: A Report on 3 Patients

We report 3 cases of patients with bronchogenic cyst arising in the posterior mediastinum. The patients were a 19-year-old male, a 36-year-old female and a 33-year-old female, whose cysts were detected as abnormal shadows in the chest. In 2 of them, neurogenic tumors were suspected preoperatively. We performed thoracoscopic resection for the 3 tumors. Bronchogenic cysts may occur ectopically, and the posterior mediastinum must be sufficiently recognized as a rare but possible ectopic site

Mediastinal Malignant Lymphoma Difficult to Diagnose : A Patient Report

We report a 58-year-old man who suffered from shortness of breath on exertion with wheezing. A chest enhanced computed tomography (CT) scan showed an irregular tumor in the middle mediastinum involving the right main pulmonary artery, vena cava superior and right main bronchus. Transbronchial lung biopsy and endobronchial ultrasoundguided transbronchial needle aspiration yielded no evidence for a pathological diagnosis of malignancy. We employed mediastinoscopy, which led to a diagnosis of lymphoid reactive change. 18F-fluorodeoxyglucose-positron emission omography (FDG-PET) scan revealed a high FDG uptake in the tumor lesion. Because the CT scan and FDG-PET findings led to a marked suspicion of malignancy, we decided to attempt biopsy by a video-assisted thoracoscopic surgery (VATS) approach. Flow cytometry showed a monoclonal pattern, and the final diagnosis was mediastinal follicular lymphoma both pathologically and immunohistologically. The patient achieved a complete remission by following chemotherapy. Lowgrade malignancy type of lymphoma such as follicular lymphoma that generally contains small-cell components often presents a diagnostic challenge and the VATS approach was effective for the diagnosis of such type of mediastinal lymphoma

使用者中心の福祉機器臨床評価手法 : プロトタイプロボティックベッドの評価

首都大学東京, 2015-03-25, 博士（作業療法学）, 甲第476号首都大学東

Case Report: Unresectable pulmonary metastases of a giant cell tumor of bone treated with denosumab: a case report and review of literature

Giant cell tumors of bone (GCTB) sometimes metastasize to distant organs. In this case report, we present pulmonary metastases of GCTB mimicking malignancies. A 49-year-old man underwent two surgical treatments for a GCTB of the right proximal radius. At the time of the second surgery, no lesions were observed on chest radiography. Three years after surgery, the patient presented with cough and dyspnea, and chest radiography and computed tomography (CT) revealed multiple lung nodules. Positron emission tomography/CT revealed a high accumulation of 18F-fluoro-2-deoxy-D-glucose (18F-FDG) in multiple lesions. Based on the rapid growth and accumulation of 18F-FDG, a metastatic malignant tumor was suspected. CT-guided needle biopsy was performed, and the histology showed proliferation of spindle cells and multinuclear giant cells without malignant changes. Denosumab was administered because multiple lung lesions were unresectable. One month after denosumab treatment, CT showed marked shrinkage of the lesions, and the symptoms significantly improved. Eighteen months after the initial treatment with denosumab, the patient had no symptoms or tumor growth. Although its long-term efficacy and safety remain unclear, denosumab may be a treatment option for patients with unresectable pulmonary GCTB