The conventional hydration number, λ, of a polymer electrolyte membrane (PEM) is estimated by the gravimetric measurement of the total water uptake in the membrane. This is the overall water molecules divided by the number of ionic groups covering the water distribution from the macroscale to the molecular level. For a more precise evaluation of the local ion-water interactions and ion transport efficiency in hydrophilic channels, in contrast to λ, we here propose an index, local hydration number (λ), defined as the number of water molecules located adjacent to and interacting with ionic groups in a PEM, per ionic group in the hydrophilic channels.
View Article and Find Full Text PDFThe structural features of a polymer electrolyte membrane (PEM), consisting of polystyrene sulfonic acid (PSSA) grafted onto poly(ethylene--tetrafluoroethylene) (ETFE), can be characterized semiquantitatively by atomic force microscopy (AFM). The cross-sectional AFM phase images are converted to the binarized image by fitting two Gaussian functions. The domains correspond to hydrophilic PSSA domains and hydrophobic ETFE crystalline and amorphous regions, respectively, at lower and higher phase shift values.
View Article and Find Full Text PDFTo develop and assess new dosage forms for the alternative to existing oral medication for peripheral neuropathy, a hydrogel film in the skin patch formation containing tramadol hydrochloride (TRA), a water-soluble drug used as an analgesic, was prepared and evaluated. A hydrogel film composed of 20%(w/w) hydroxypropyl methylcellulose (HPMC) irradiated with electron beams had high transparency and elasticity similar to commercially available wound dressings and soft tissues, suggesting that it is a suitable substrate for TRA. The inclusion of TRA was enabled by immersing the HPMC hydrogel film in TRA aqueous solution.
View Article and Find Full Text PDFBackground: TP0473292 (the active ingredient of TS-161) is a prodrug of a novel metabotropic glutamate (mGlu) 2/3 receptor antagonist being developed for the treatment of patients with depression. This study evaluated the safety, tolerability, and pharmacokinetics of orally administered TS-161 in healthy subjects.
Methods: This was a first-in-human, phase 1, randomized, double-blind, placebo-controlled, single-ascending dose (15-400 mg TS-161) and 10-day multiple-ascending dose (50-150 mg TS-161) study in healthy subjects, conducted from June 2019 through February 2020.
Newly designed styrylimidazolium-based grafted anion-exchange membranes (StIm-AEMs), in which imidazolium ionic groups are attached to styrene at the far side from the graft chains, were prepared by radiation-induced graft polymerization of p-(2-imidazoliumyl) styrene onto poly(ethylene-co-tetrafluoloethylene) (ETFE) films, followed by N-alkylation and ion-exchange reactions. StIm-AEM having an ion exchange capacity (IEC) of 0.54 mmol g-1 with a grafting degree (GD) of ∼18%, possesses practical conductivity (>50 mS cm-1) even with a very low water uptake (∼10%) and high stability over 600 h in a 1 M KOH solution at 80 °C.
View Article and Find Full Text PDFWe found unprecedented reverse relationships in anion-exchange membranes (AEMs) for Pt-free alkaline fuel cell systems, i.e., the increase in hydrophobicity increased water uptake and susceptibility to hydrolysis.
View Article and Find Full Text PDFWe have proposed a novel polymer gel dosimeter containing of 2-hydroxyethyl methacrylate (HEMA), nonaethylene glycol dimethacrylate (9G), and tetrakis (hydroxymethyl) phosphonium chloride (THPC) with radiation-crosslinked hydroxypropyl cellulose (HPC) gel sheet. The transparent sheet-type dosimeters became white and cloudy by irradiation with gamma-rays and heavy ions such as He ions (150 MeV/u), C ions (290 MeV/u), Fe ions (500 MeV/u). The cloudiness increased with increasing dose.
View Article and Find Full Text PDFIn our previous study (Soft Matter, 2016, 12, 1567), the relationship between the morphology and properties of graft-type imidazolium-based anion exchange membranes (AEMs) was revealed, in that the semi-crystalline features of the polymer matrix maintain its mechanical properties and the formation of interconnected hydrophilic domains promotes the membrane conductivity. Here, we report a novel ionic structure of the same graft-type AEMs with different grafting degrees, analyzed using a small-angle X-ray scattering method under different relative humidity (RH) conditions. The characteristic "ionomer peak" with a corresponding correlation distance of approximately 1.
View Article and Find Full Text PDFWe performed studies on pulse radiolysis of highly transparent and shape-stable hydrogels of hydroxypropyl cellulose (HPC) that were prepared using a radiation-crosslinking technique. Several fundamental aspects of radiation-induced chemical reactions in the hydrogels were investigated. With radiation doses less than 1 kGy, degradation of the HPC matrix was not observed.
View Article and Find Full Text PDFPhys Med Biol
October 2013
New polymer gel dosimeters consisting of 2-hydroxyethyl methacrylate (HEMA), triethylene glycol monoethyl ether monomethacrylate (TGMEMA), polyethylene glycol 400 dimethacrylate (9G), tetrakis (hydroxymethyl) phosphonium chloride as an antioxidant, and gellan gum as a gel matrix were prepared. They were optically analyzed by measuring absorbance to evaluate a dose response. The absorbance of the polymer gel dosimeters that were exposed to (60)Co γ-rays increased with increasing dose.
View Article and Find Full Text PDFA 43-year-old man with schizophrenia presented to our hospital with appetite loss and general fatigue lasting 1-2 months. His face was flared and swollen, and he shed tears of pus. He could answer any questions, but never complained of pain.
View Article and Find Full Text PDFProper instruction is essential for evaluating muscular endurance with high reliability. This study aimed to examine the influence of instruction conditions on the evaluation of rhythmic repeated muscular endurance based on muscle oxygenation kinetics. Fifteen healthy young men performed repeated maximal rhythmic grips for 6 minutes under the following 3 instruction conditions: (1) "Squeeze as hard as you can during 2 seconds freely (Ex1)"; (2) "Squeeze as hard as you can quickly at the cue of a beep every 2 seconds (Ex2)"; and (3) "Squeeze as hard as you can quickly at the cue of a beep every 2 seconds, and then hold the exertion for 1 second (Ex3)".
View Article and Find Full Text PDFThe thermal decomposition of hydrogen peroxide, H(2)O(2), was determined in aqueous suspensions of SiO(2), Al(2)O(3), TiO(2), CeO(2), and ZrO(2) nanometer-sized particles. First-order kinetics were observed for the decomposition in all cases. Temperature dependence studies found that the activation energy was 42 +/- 5 kJ/mol for the overall decomposition of H(2)O(2) independent of the type of oxide.
View Article and Find Full Text PDFThe depsipeptide Boc(1)-Leu(2)-Leu(3)-Ala(4)-Leu(5)-Leu(6)-Lac(7)-Leu(8)-Leu(9)-Lac(10)-Leu(11)-Leu(12)-Lac(13)-Leu(14)-Leu(15)-OEt(16) (1) (Boc = tert-butyloxycarbonyl, Lac = L-lactic acid residue) has been synthesized from the peptide Boc-Leu-Leu-Ala-OEt (2) and a depsipeptide, Boc-(Leu-Leu-Lac)(3)-Leu-Leu-OEt (3). Single crystals of 1 were successfully obtained and the structure has been solved by direct methods (such as Sir2002 and Shake-and-Bake). Interestingly, 1 adopts an alpha/3(10)-conjugated helix containing a kink at the junction of peptide and depsipeptide segments, Leu3-Lac7.
View Article and Find Full Text PDFBiomed Pharmacother
October 2003
We set up a screening system to detect low-molecular-weight compounds that induce insulin expression in pancreatic acinar carcinoma AR42J cells. They can differentiate into insulin-producing cells with neuron-like morphological change when treated with activin A. We employed this morphological change for the screening of beta-cell inducers among various signal transduction inhibitors.
View Article and Find Full Text PDFEt-3,4-dephostatin, a protein-tyrosine phosphatase (PTPase) inhibitor, potentiates insulin-dependent signal transduction and shows an antidiabetic effect in mice. However, it contains a nitrosamine moiety that is often mutagenic and carcinogenic. Therefore, we previously designed and synthesized methoxime-3,4-dephostatin as a nitrosamine-free analogue of dephostatin.
View Article and Find Full Text PDFIn order to clarify the relationship between the crosslinked structure of thermo-responsive polymer and drug release profile, polymer gels based on acryloyl-L-proline methyl ester (A-ProOMe) were synthesized in a mixture of water and acetone by the following two methods: a simultaneously occurring process of radiation-induced polymerization and crosslinking without a crosslinker (self-bridging method), and radiation-induced polymerization in the presence of the crosslinker tetradecaethylene glycol dimethacrylate (crosslinker method). The pronounced gap in thermo-response between two A-ProOMe gels, with an apparent degree of crosslinking of 11 for 1-propanol, shows a different shrinking pattern in the initial stage of time. The gels, which were obtained with the self-bridging method and the crosslinker method, were kept constant at a swelling ratio of 17 in water at 0 degree C for all systems.
View Article and Find Full Text PDFWe previously isolated dephostatin from Streptomyces as a novel inhibitor of CD45-associated protein-tyrosine phosphatase. We prepared Et-3,4-dephostatin as a stable analogue and found it to inhibit PTP-1B and SHPTP-1 protein-tyrosine phosphatases selectively but not to inhibit CD45 and leukocyte common antigen-related phosphatase ones effectively. Et-3,4-dephostatin increased the tyrosine phosphorylation of the insulin receptor and insulin receptor substrate-1 with or without insulin in differentiated 3T3-L1 mouse adipocytes.
View Article and Find Full Text PDFSwelling-controlled drug delivery copolymer gels were newly synthesized by introducing thermo- and pH-responsive methacryloyl-glycine (MA-Gly) or pH-responsive methacrylic acid (MA-Ac) for comparison with thermoresponsive acryloyl-L-proline ethyl ester (A-ProOEt). A homopolymer gel of A-ProOEt was kept at degrees of swelling that were less than 0.5 at a pH from 2.
View Article and Find Full Text PDFOral Surg Oral Med Oral Pathol Oral Radiol Endod
November 1996
We examined 37 patients who had undergone an allogeneic bone marrow transplantation and compared their oral findings to their systemic involvement with chronic graft-versus-host disease. Among the clinical signs and symptoms in their oral region, only the presence of oral lichenoid lesions had a statistically significant relationship to the diagnosis of chronic graft-versus-host disease. The histologic findings in the labial salivary glands and buccal mucosa closely reflected the status of chronic graft-versus-host disease.
View Article and Find Full Text PDFCancer Immunol Immunother
September 1996
Oral squamous cell carcinomas (SCC) are often infiltrated by a large number of T lymphocytes. To clarify the nature of the tumour-infiltrating lymphocytes (TIL), we examined T cell receptor (TCR) V alpha and V beta gene usage by TIL and peripheral blood mononuclear cells (PBMC) obtained from 10 patients with oral SCC. We obtained RNA from TIL and PBMC, synthesized complementary DNA, and used the polymerase chain reaction (PCR) method with a panel of primers specific for the V gene segment subfamily (V alpha 1-18/V beta 1-20).
View Article and Find Full Text PDFInt J Oral Maxillofac Surg
August 1996
Patients with chronic graft-versus-host disease (cGVHD) occasionally suffer from symptoms of xerostomia and xerophthalmia, which are also features of Sjógren's syndrome (SS). To identify differences in the glandular involvement between cGVHD and SS, we measured the proportions of infiltrating lymphocyte subsets and the expression of HLA-DR antigen and cell adhesion molecules in labial salivary glands (LSG). In cGVHD, more than 90% of the infiltrating lymphocytes were T cells with a slight predominance of CD8+ over CD4+ cells.
View Article and Find Full Text PDFObjective: To characterize the initiation and progress of localized autoimmune damage in Sjögren's syndrome (SS), an autoimmune disease that is also considered to be a lymphoaggressive disorder, by examining the pattern of cytokine production at the site of autoimmune damage.
Methods: Using a polymerase chain reaction-based method, cytokine messenger RNA (mRNA) expression in the labial salivary glands of 15 patients with SS was investigated. In addition, the infiltrating lymphocytes in the labial salivary glands were examined immunohistochemically.
The major histocompatibility complex (MHC) class II antigens have been reported to play an important role in antigen presentation to T cells and influence the susceptibility to several autoimmune diseases, including Sjögren's syndrome (SS). In this paper, an aberrant expression of MHC class II antigens, especially HLA-DR antigens, on salivary glands of SS is described. HLA-DR antigens were immunohistochemically detected on acinar and ductal epithelial cells of SS patients but not those of healthy controls.
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