142 research outputs found

    Product analysis of caffeic acid oxidation by on-line electrochemistry/electrospray ionization mass spectrometry

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    AbstractOn-line electrochemistry/electrospray ionization mass spectrometry (EC/ESI-MS) was developed using a microflow electrolytic cell. This technique was applied to electrochemical oxidation of caffeic acid (CAF) which is known to be a highly antioxidative agent. Effects of electrolytic potentials on ion intensities of product ions and on electrolytic currents were examined at different pHs. Dimer products were detected at electrolytic potentials of E = 0.7 V (vs. Ag/AgCl) and trimer products at 1.0 V at pH 9. Dimer products were distinguished from hydrogen-bonded complexes by MS/MS experiments. Hydrogen/deuterium exchange experiments determined the number of hydroxyl and carboxyl groups in the Dimers formed by electrolysis. The mechanism of oxidative polymerization of CAF is discussed with speculation as to the structure of the dimer product

    How Viscous Is the Solidlike Structure at the Interface of Ionic Liquids? A Study Using Total Internal Reflection Fluorescence Spectroscopy with a Fluorescent Molecular Probe Sensitive to High Viscosity

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    Aiming at the evaluation of the viscosity of the interfacial solidlike structure of ionic liquids (ILs), we performed total internal reflection fluorescence (TIRF) spectroscopy for N, N-diethyl-N′-phenyl-rhodamine (Ph-DER), a fluorescent probe that is sensitive to viscosity in a high-viscosity range. TIRF spectra at the glass interface of trioctylmethylammonium bis(nonafluorobutanesulfonyl)amide (TOMAC4C4N), a hydrophobic IL, showed that the fluorescence intensity of Ph-DER increases with the decrease of the evanescence penetration depth, suggesting that there exists a high-viscosity region at the interface. In contrast, glycerol, which is a molecular liquid with a bulk viscosity similar to that of TOMAC4C4N, did not show such a fluorescence increase, supporting that the formation of a highly viscous solidlike structure at the interface is intrinsic to ILs. A model analysis suggested that the high viscous region at the glass interface of TOMAC4C4N is at least twice thicker than the ionic multilayers at the air interface, implying that the solid substrate enhances the ordering of the interfacial structure of ILs. The viscosity at the glass interface of TOMAC4C4N was found to be at least 40 times higher than that of the liquid bulk

    Laparoscopic extra-abdominal suturing technique for the repair of Larrey’s diaphragmatic hernia using the port closure needle (Endo Close®): A case report

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    AbstractIntroductionMorgagni’s or Larrey’s diaphragmatic hernias are relatively uncommon. If the defect is too large for primary closure, the use of a mesh is inevitable. Although primary closure is adaptable for relatively small defects, it is difficult to suture the hernial orifice in which the anterior rim is absent. Herein, we present the case of a patient with Larrey’s diaphragmatic hernia that was easily and securely repaired using the recently developed laparoscopic extra-abdominal suturing technique via the port closure needle (Endo Close®; Medtronic, Minneapolis, USA).Presentation of caseAn 89-year-old woman complaining of vomiting was transferred to our hospital. Computed tomography scan showed Larrey’s diaphragmatic hernia. Laparoscopic repair was performed after gastric decompression. We diagnosed Larrey’s hernia on the left side of the falciform ligament. The transverse colon was herniated through the defect. Since the hernial defect was located below the substernal space, there was no tissue to stitch at the anterior rim of the hernial orifice. We performed the extra-abdominal suturing technique, suturing the posterior rim of the hernia to the full thickness of the anterior abdominal wall using the port closure needle (Endo Close®) without the need for a mesh. The patient was discharged on the 8th postoperative day. There was no evidence of recurrence at 8 months postoperatively.DiscussionThe recently developed extra-abdominal suturing technique using Endo Close® to suture the full thickness of the anterior abdominal wall achieved secure mattress suture and easy extra-abdominal tying.ConclusionThis method may be useful in terms of easiness and security of suture

    Nonextensive Entropies derived from Form Invariance of Pseudoadditivity

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    The form invariance of pseudoadditivity is shown to determine the structure of nonextensive entropies. Nonextensive entropy is defined as the appropriate expectation value of nonextensive information content, similar to the definition of Shannon entropy. Information content in a nonextensive system is obtained uniquely from generalized axioms by replacing the usual additivity with pseudoadditivity. The satisfaction of the form invariance of the pseudoadditivity of nonextensive entropy and its information content is found to require the normalization of nonextensive entropies. The proposed principle requires the same normalization as that derived in [A.K. Rajagopal and S. Abe, Phys. Rev. Lett. {\bf 83}, 1711 (1999)], but is simpler and establishes a basis for the systematic definition of various entropies in nonextensive systems.Comment: 16 pages, accepted for publication in Physical Review

    Antioxidant capacity of albumin-bound quercetin metabolites after onion consumption in humans

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    Quercetin is a major dietary flavonoid found in onions and other vegetables. It is known that dietary quercetin is metabolized in the intestinal mucosa and the liver and is present as its glucuronide/sulfate conjugates with or without methylation. Although quercetin is known to possess strong antioxidant activity, there are only limited reports on the antioxidant activity of its metabolites. In this study, the antioxidant capacity of quercetin metabolites under physiological conditions was investigated. After consumption of cooked onion, more than 80% of quercetin metabolites were localized in the human plasma fraction containing concentrated serum albumin. Other lipoprotein fractions contained only small amounts of quercetin metabolites. Addition of quercetin 3-O-β-glucuronide to the lipoprotein-eliminated plasma fraction generated antioxidant activity against LDL oxidation in a dose-dependent manner. However, onion consumption failed to enhance the antioxidant activity of the lipoprotein-eliminated plasma fraction against LDL oxidation, probably because the amount of quercetin metabolites bound to albumin was less than the effective level in an ex vivo study. The physiological role of plasma albumin in retaining quercetin metabolites needs to be further clarified

    CIPRO 2.5: Ciona intestinalis protein database, a unique integrated repository of large-scale omics data, bioinformatic analyses and curated annotation, with user rating and reviewing functionality

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    The Ciona intestinalis protein database (CIPRO) is an integrated protein database for the tunicate species C. intestinalis. The database is unique in two respects: first, because of its phylogenetic position, Ciona is suitable model for understanding vertebrate evolution; and second, the database includes original large-scale transcriptomic and proteomic data. Ciona intestinalis has also been a favorite of developmental biologists. Therefore, large amounts of data exist on its development and morphology, along with a recent genome sequence and gene expression data. The CIPRO database is aimed at collecting those published data as well as providing unique information from unpublished experimental data, such as 3D expression profiling, 2D-PAGE and mass spectrometry-based large-scale analyses at various developmental stages, curated annotation data and various bioinformatic data, to facilitate research in diverse areas, including developmental, comparative and evolutionary biology. For medical and evolutionary research, homologs in humans and major model organisms are intentionally included. The current database is based on a recently developed KH model containing 36 034 unique sequences, but for higher usability it covers 89 683 all known and predicted proteins from all gene models for this species. Of these sequences, more than 10 000 proteins have been manually annotated. Furthermore, to establish a community-supported protein database, these annotations are open to evaluation by users through the CIPRO website. CIPRO 2.5 is freely accessible at http://cipro.ibio.jp/2.5

    Hemangiopericytoma in the sacrococcygeal space: a case report

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    <p>Abstract</p> <p>Introduction</p> <p>A hemangiopericytoma is a rare, soft-tissue tumor of vascular origin derived from a pericyte of Zimmerman, which is a modified smooth muscle cell that surrounds the small blood vessels. Hemangiopericytomas can occur wherever there are vascular capillaries. However, there are no previous reports of a hemangiopericytoma in the sacrococcygeal space.</p> <p>Case presentation</p> <p>We describe the first reported case of a hemangiopericytoma found in the sacrococcygeal space. A 47-year-old Japanese woman presented with a palpable tumor on the left side of her anus. Preoperative imaging indicated that the tumor was in the sacrococcygeal space without invasion of other organs. A complete resection was performed via a parasacral incision. The histological and immunohistochemical staining patterns supported the diagnosis of a hemangiopericytoma.</p> <p>Conclusion</p> <p>A complete resection without piecemeal excision is the best way to treat a hemangiopericytoma. Recognizing the presence of a hemangiopericytoma in the sacrococcygeal space requires appropriate surgery.</p
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