348 research outputs found

    Effect of moisture in κ-carrageenan films on their tensile and relaxation behavior studied by correlation between stress and birefringence

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    A picture on the molecular level describing the deformation and the following relaxation of κ-carrageenan chains has been proposed based on the three-domain structural model for κ-carrageenan films and on the idea of the modified stress-optical rule. The uniaxial tensile and the relaxation behavior for dry and moist κ-carrageenan films has been examined by using a homemade apparatus available for the simultaneous mechanical and birefringence measurements. It has been suggested that the continuous amorphous phase of κ-carrageenan in the dry film is deformed together with the local glass component, and only the glass component relaxes in the following process. On the other hand, concerning the moist film, the crosslinks of κ-carrageenan aggregates in addition to the continuous phase are movable with deformation, while the following relaxation is attributed only to the unbridged κ-carrageenan chains in the continuous phase

    Effects of gelation concentration on cyclic deformation behavior of κ-carrageenan hydrogels

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    The aim of this study is to elucidate the relationship between the network structure of κ-carrageenan hydrogels and their mechanical properties. First κ-carrageenan hydrogels have been prepared at different gelation concentrations, and then the mechanical behavior during four cyclic deformations has been examined at the same κ-carrageenan concentration. Young's modulus is higher for the gel prepared at 5 gL⁻¹ (C05) compared to that for the gel prepared at 30 gL⁻¹ (C30). C30 shows almost linear relation between the stress and the strain like an ideal rubber, while a residual strain appears in each cyclic deformation for C05. The extent of the residual strain depends on the maximum strain and the deformation speed, indicating that C05 deforms plastically to some extent. The residual strain for C05 decreases gradually even after a cyclic deformation and disappears in the case of a small strain as if there were a memory of the structure. The effects of the gelation concentration on the mechanical properties have been explained based on the network structure specific to κ-carrageenan hydrogels. The higher modulus for C05 has been attributed to the higher helix content and the plastic deformation of C05 to the loosely-aggregated crosslinks

    Effect of p-d hybridization and structural distortion on the electronic properties of AgAlM2 (M = S, Se, Te) chalcopyrite semiconductors

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    We have carried out ab-initio calculation and study of structural and electronic properties of AgAlM2 (M = S, Se, Te) chalcopyrite semiconductors using Density Functional Theory (DFT) based self consistent Tight binding Linear Muffin Tin orbital (TB-LMTO) method. Calculated equlibrium values of lattice constants, anion displacement parameter (u), tetragonal distortion ({\eta} = c/2a) and bond lengths have good agreement with experimental values. Our study suggests these semiconductors to be direct band gap semiconductors with band gaps 1.98 eV, 1.59 eV and 1.36 eV respectively. These are in good agreement with experimental value within the limitation of local density approximation (LDA). Our explicit study of the effects of anion displacement and p-d hybridization show that band gap increases by 9.8%, 8.2% and 5.1% respectively for AgAlM2 (M = S, Se, Te) due to former effect and decreases by 51%, 47% and 42% respectively due to later effect.Comment: 15 pages, 17 figures, This article has been communicated to Solid State Communication

    難治性の良性発作性頭位めまい症はヘッドアップした姿勢で就寝することにより治り得る:6ヶ月間のランダム化比較試験

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    Objectives: The aim of the present study was to assess head-position management for intractable idiopathic benign paroxysmal positional vertigo (BPPV) when lying down. We hypothesized that head-up sleep (HUS) could prevent free-floating otoliths from entering the semicircular canals. Study design: A prospective two-arm multicenter randomized controlled trial. Methods: BPPV was diagnosed in 611 patients (611/1,520; 40.2%) according to the 2015 diagnostic guidelines issued by the International Classification of Vestibular Disorders. Among them, 201 patients were intractable (201/611; 32.9%), 88 of whom were idiopathic and subsequently enrolled in the study. Patients randomly received intervention with HUS at greater than 45° (n = 44) or head-down sleep (HDS; n = 44) when lying down. Before treatment, they completed several examinations, including subjective visual vertical (SVV). The specific diagnoses for the 88 patients with BPPV included horizontal type cupula (n = 40), horizontal type canal (n = 13), posterior type (n = 26), and probable and/or atypical BPPV (n = 9). Results: Patient backgrounds did not differ significantly between the HUS and HDS groups. Visual analog scale (VAS) scores of vertiginous sensation were significantly lower in the HUS group than in the HDS group at both the third month and sixth month post-treatment. Positional/positioning nystagmus observed just before treatment disappeared significantly more often in the HUS group than in the HDS group until the sixth post-treatment month. Further, especially in HUS group, VAS scores in SVV- group (n = 24) were significantly lower than those in the SVV+ group (n = 20) sixth month post-treatment. Conclusions: Controlling free-floating otoliths is not easy due to aging of the otolith organs. Repeatedly returning the endless free-floating debris from the canals to the utricle through physical means is not a good strategy. Therefore, HUS when lying down at home could be recommended as an initial treatment for patients with intractable idiopathic BPPV. Level of evidence: 1b.博士(医学)・甲第764号・令和3年3月15日© 2019 The Authors. Laryngoscope Investigative Otolaryngology published by Wiley Periodicals, Inc. on behalf of The Triological Society. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License (http://creativecommons.org/licenses/by-nc-nd/4.0/), which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made

    Chalcones and Dihydrochalcones Augment TRAIL-Mediated Apoptosis in Prostate Cancer Cells

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    Chalcones and dihydrochalcones exhibit chemopreventive and antitumor activity. TRAIL (tumor necrosis factor-related apoptosis-inducing ligand) is a natural endogenous anticancer agent. We examined the cytotoxic and apoptotic effect of chalcones and dihydrochalcones on TRAIL-mediated apoptosis in LNCaP prostate cancer cells. The cytotoxicity was evaluated by the MTT and LDH assays. The apoptosis was detected using annexin V-FITC by flow cytometry and fluorescence microscopy. The ΔΨm was evaluated using DePsipher staining by fluorescence microscopy. Our study showed that two tested chalcones (chalcone and 2’,6’dihydroxy-4’-methoxychalcone) and three dihydrochalcones (2’,6’-dihydroxy-4’4-dimethoxydihydrochalcone, 2’,6’-dihydroxy-4’-methoxydihydro- chalcone,  and 2’,4’,6’-trihydroxydihydrochalcone, called phloretin) markedly augmented TRAIL-induced apoptosis and cytotoxicity in LNCaP cells and confirmed the significant role of chalcones in chemoprevention of prostate cancer

    Predictive Value of the Cardio-Ankle Vascular Index for Cardiovascular Events in Patients at Cardiovascular Risk

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    BACKGROUND: Arterial stiffness is an important predictor of cardiovascular events; however, indexes for measuring arterial stiffness have not been widely incorporated into routine clinical practice. This study aimed to determine whether the cardio-ankle vascular index (CAVI), based on the blood pressure-independent stiffness parameter beta and reflecting arterial stiffness from the origin of the ascending aorta, is a good predictor of cardiovascular events in patients with cardiovascular disease risk factors in a large prospective cohort. METHODS AND RESULTS: This multicenter prospective cohort study, commencing in May 2013, with a 5-year follow-up period, included patients (aged 40-74 years) with cardiovascular disease risks. The primary outcome was the composite of cardiovascular death, nonfatal stroke, or nonfatal myocardial infarction. Among 2932 included patients, 2001 (68.3%) were men; the mean (SD) age at diagnosis was 63 (8) years. During the median follow-up of 4.9 years, 82 participants experienced primary outcomes. The CAVI predicted the primary outcome (hazard ratio, 1.38; 95% CI, 1.16-1.65; P CONCLUSIONS: This large cohort study demonstrated that the CAVI predicted cardiovascular events

    Chalcones Enhance TRAIL-Induced Apoptosis in Prostate Cancer Cells

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    Chalcones exhibit chemopreventive and antitumor effects. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a naturally occurring anticancer agent that induces apoptosis in cancer cells and is not toxic to normal cells. We examined the cytotoxic and apoptotic effect of five chalcones in combination with TRAIL on prostate cancer cells. The cytotoxicity was evaluated by the MTT and LDH assays. The apoptosis was determined using flow cytometry with annexin V-FITC. Our study showed that all five tested chalcones: chalcone, licochalcone-A, isobavachalcone, xanthohumol, butein markedly augmented TRAIL-mediated apoptosis and cytotoxicity in prostate cancer cells and confirmed the significant role of chalcones in chemoprevention of prostate cancer

    A phase II study of S-1 monotherapy administered for 2 weeks of a 3-week cycle in advanced gastric cancer patients with poor performance status

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    Systemic chemotherapy for gastric cancer is often associated with treatment-related toxicity, which is particularly severe in patients with a poor performance status. In this paper, we describe the first study to evaluate S-1 monotherapy as an option for advanced gastric cancer patients who are not candidates for combination chemotherapy due to poor clinical condition. Fifty-two patients with Eastern Cooperative Oncology Group (ECOG) performance scale 2–3, whose general condition had made use of combination chemotherapy impossible, were enrolled. S-1 was administered to 30 patients as second- or third-line therapy. The initial dose of S-1 was 35 mg m−2, administered b.i.d for 14 days every 3 weeks. With a median follow-up period of 33 weeks, the median progression-free survival, and overall survival were 11 weeks (95% CI, 8–14) and 33 weeks (95% CI, 19–47), respectively. The overall 1-year survival rate was 29% by intent-to-treat analysis. The overall response rate was 12% (95% CI, 3–21), and the percentage of stable disease was 35%, resulting in the disease control rate of 47% (95% CI, 32–60). Significant drug-related toxicity included grade 3 diarrhoea (14%), anorexia (14%), fatigue (10%), neutropenia (10%), and leucopenia (6%). In conclusion, this study indicated the modest activity of S-1 in gastric cancer patients with poor performance status
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