Deformation Behavior of Body-Centered Cubic Lattice in Polymers.

A body-centered cubic (BCC) lattice is a crystal unit cell structure observed in metals, inorganics, and polymers. The deformation behavior of the BCC lattice in metals has been well elucidated, whereas that of polymers remains unclear. We used a microphase-separated copolymer with randomly oriented grains wherein spherical phases are packed in the BCC lattice.

Specific deformation behavior of isotactic polypropylene films under a multiaxial stress field.

The specific deformation behavior of crystalline polymer films, namely unoriented crystallized isotactic polypropylene ( PP) films, was investigated under a multiaxial stress field. Changes in the aggregation structure of the films were investigated during the bulge deformation process using small-angle X-ray scattering, wide-angle X-ray diffraction (WAXD) measurements, and polarized high-speed-camera observations. The films had a thickness of approximately 10 μm.

Primary Aldosteronism with Parathyroid Hormone Elevation: A Single-center Retrospective Study.

Objective Primary aldosteronism (PA) is a major cause of secondary hypertension. The association between PA and other hormone disorders is unclear. The present study aimed to evaluate whether the parathyroid hormone (PTH) value is associated with PA subtypes or specific treatments.

Effect of sodium glucose cotransporter 2 inhibitors on obstructive sleep apnea in patients with type 2 diabetes.

Obstructive sleep apnea syndrome (OSAS) is often associated with metabolic disorders such as obesity and type 2 diabetes and may contribute to cardiovascular events. A novel class of antidiabetic drugs, the sodium glucose cotransporter 2 inhibitors (SGLT2i) reduce body weight (BW), although there is limited data on their impact on OSAS. We therefore evaluated the effect of SGLT2i on OSAS in patients with type 2 diabetes.

In situ synchrotron radiation X-ray diffraction studies on molecular aggregation structure of nylon 12 films during bulge testing.

It is desirable to establish a method for evaluating mechanical properties, such as modulus and strength, of micrometer and sub-micrometer thick polymer films. Bulge tests, where bulge deformation is imposed on films by the pressure of an inert gas, are suitable for satisfying this demand. However, very few studies on polymer films exist in the literature.

High frequency of type 2 diabetes and impaired glucose tolerance in Japanese subjects with the angiopoietin-like protein 8 R59W variant.

Background: Angiopoietin-like protein 8 (ANGPTL8) is considered to be metabolically multifunctional. One notable function still to be elucidated definitively is a betatrophic role in protecting and preserving pancreatic beta-cell function. There is, however, a paucity of data regarding the role of ANGPTL8 in the etiology of type 2 diabetes (T2D), but some findings of human research have suggested the potential for significant involvement.

Biobased Polymer Coating Using Catechol Derivative Urushiol.

We have investigated the mechanism of the superior mechanical robustness of coated thin films of the catechol derivative urushiol. We synthesized hydrogenated urushiol (h-urushiol) by hydrogenating the double bonds in the long alkyl side chain of urushiol, and the physical properties of thin films of mixtures of urushiol and h-urushiol were evaluated. Atomic force microscopy observations revealed that these coated thin films have a homogeneous surface with no phase separation, regardless of the h-urushiol content, arising from the similarity of the chemical structures.

Spray-assisted nanocoating of the biobased material urushiol.

We have demonstrated the spray-assisted coating of the catechol derivative, urushiol. Spraying a mixture of urushiol and iron(II) acetate formed a uniform coating about 10 nm thick, as confirmed by AFM observations. XPS measurements revealed that various substrates, including polyolefins and thermosetting resins, were successfully coated with urushiol.

Surface functionalization by decal-like transfer of thermally cross-linked urushiol thin films.

We have demonstrated surface functionalization through the decal-like transfer of thermally cross-linked urushiol thin films onto various substrates. Tensile adhesive strength measurements showed that the film adheres strongly to the surface of various substrates including chemically inert materials, such as polyolefins and thermosetting resins, because of the properties of urushiol. Furthermore, the highly cross-linked structure of urushiol made the films mechanically robust.

Scaffold for growing dense polymer brushes from a versatile substrate.

We have demonstrated a universal approach to growing polymer brushes from various substrates. Urushiol was mixed with initiator-containing catechol, and it was spin-coated or cast on various substrates. Because urushiol is strongly adhered to various substrates, the thin film can serve as a general scaffold for grafting polymer brushes from various substrates.

Robust liquid marbles stabilized with surface-modified halloysite nanotubes.

We have demonstrated the fabrication of fluorine-free liquid marbles from halloysite nanotube. Halloysite is a naturally occurring inorganic nanotube that has a high aspect ratio, and the surface was modified with octadecyltrimethoxysilane. The surface-modified halloysite formed pincushion agglomerates on the surface of the liquid droplets, which create superhydrophobic surface similar to that of the plant gall surface prepared by aphids.

Chemical evidence for the synergistic effect of a cysteinyl thiol on the antioxidant activity of caffeic and dihydrocaffeic esters.

Antioxidant activity of methyl caffeate and methyl dihydrocaffeate in the presence of a cysteinyl thiol was measured in an azo-initiator-induced lipid oxidation system. The coexistence of the thiol was observed to display a synergistic effect on the antioxidant activity of both caffeates. The synergism was observed mainly with respect to the elongation of the induction period, rather than the inhibition rate for lipid oxidation.

Concealing surface topography by attachment of nanometer-thick film.

Concealing of surface topology of substrates by decal-like attachment of nanomembrane is demonstrated. The nanomembrane attachment provides a flat surface on various substrates, including porous substrates, and the surface property such as wettability was changed to that of the nanomembrane. The monitoring of drying process revealed that a nanomembrane with certain thickness tolerates their flexural deflection during the procedure.

Curcumin: from chemistry to chemistry-based functions.

Curcumin is a yellow pigment found in the spice turmeric and a main functional constituent of the rhizomes of Curcuma longa. The multi-functionality of curcumin has recently attracted much attention in various fields, including food, medicinal, and clinical industries. Three major curcuminoids, curcumin, demethoxycurcumin, and bis-demethoxycurcumin, are distributed in not only Curcuma, but also the Zingiber species; however, distribution of other curcuminoids is very limited in nature.

Chemical interaction between polyphenols and a cysteinyl thiol under radical oxidation conditions.

Chemical interaction between polyphenols and thiols was investigated under radical oxidation conditions using a model cysteinyl thiol derivative, N-benzoylcysteine methyl ester. The radical oxidation was carried out with a stoichiometric amount of 2,2-diphenyl-1-picrylhydrazyl (DPPH), and the decreases in the amounts of polyphenols and the thiol were measured by HPLC analysis. Cross-coupling products between various polyphenols and the thiol were examined by LC-MS in reactions that showed decreases in both the polyphenols and the thiol.

Synthesis of manzacidin A and C: efficient construction of quaternary carbon stereocenters bearing nitrogen substituents.

An efficient synthetic method for stereoselective construction of asymmetric quaternary carbon stereocenters, bearing nitrogen in the form of Boc-protected allyl amines, has been developed. This methodology is employed in the synthesis of marine alkaloids, manzacidin A and C.

Structure and function of the oxidation products of polyphenols and identification of potent lipoxygenase inhibitors from Fe-catalyzed oxidation of resveratrol.

Polyphenols have recently attracted much attention as potent antioxidants and related bioactive substances. These potent antioxidative polyphenols are very oxidizable due to their chemical properties, and their oxidation products must accumulate in the oxidizing foods when they are contained as the active ingredients. In this investigation, 30 polyphenols and related phenolics were oxidized with oxygen in the presence of a catalytic amount of Fe ions.

Syntheses of secocyclolignanes and comparative antioxidative activity between secocyclolignane and the dibenzyl type of lignan.

The antioxidative activity of secocyclolignanes was compared with that of the corresponding dibenzyl lignans for the first time. The radical scavenging activity of the secocyclolignanes was weaker than that of the corresponding dibenzyl lignans, the butane diol type showing the highest activity. The butane type of secocyclolignane exhibited the highest antioxidant activity of the unsaturated fatty acid.

A novel ring-expanded product with enhanced tyrosinase inhibitory activity from classical Fe-catalyzed oxidation of rosmarinic acid, a potent antioxidative Lamiaceae polyphenol.

The iron-ion catalyzed oxidation of the ethanol solution of rosmarinic acid, a potent antioxidant polyphenol of Lamiaceae (Labiatae) plants, afforded a highly tyrosinase-inhibitory active product. The structure of the active product in the oxidation product mixture was determined using extensive NMR spectroscopy to have a novel oxygen-containing seven-membered ring system. The formation mechanism of the unique ring structure from the catechol part of the rosmarinic acid was proposed.

Identification of cytotoxic dimers in oxidation product from sesamol, a potent antioxidant of sesame oil.

Phytophenols of edible plants have recently attracted much attention as potent antioxidants and related bioactive substances. These antioxidative phytophenols are very oxidizable due to their chemical properties, and their oxidation products must accumulate in the oxidizing foods when they are contained as active ingredients. In this investigation, several phytophenols, which are well known as potent antioxidants in food science, were oxidized by oxygen in the presence of a catalytic amount of Ferric ion.

Apoptosis-inducing action of two products from oxidation of sesamol, an antioxidative constituent of sesame oil: a possible cytotoxicity of oxidized antioxidant.

Many effects of sesamol, an antioxidative constituent of sesame oil, have been reported for human health benefits due to its antioxidative action. However, we recently isolated two cytotoxic products, trimer and tetramer of sesamol, from oxidation of sesamol by an assay-guided purification. In this study, we have revealed some cytotoxic characteristics of these products in rat thymocytes and human leukemia K562 cells.

Phenolic inhibitors of chemical and enzymatic oxidation in the leaves of Myrica rubra.

Potent inhibitory activity of the leaves of Myrica rubra against both chemical and enzymatic (tyrosinase and lipoxygenase) oxidation was found in our project to develop utility of unused and rarely used plant resources in the local area. A constituent analysis of the most active ethyl acetate-soluble part of a methanol extract of the leaves clarified the structures of eight major compounds. The tyrosinase and lipoxygenase inhibitory activities and DPPH radical scavenging activity of the isolated compounds were measured as indicators of the inhibitory capacity against the enzymatic and chemical oxidation of food.

Cytometric analysis of cytotoxicity of polyphenols and related phenolics to rat thymocytes: potent cytotoxicity of resveratrol to normal cells.

The chemopreventive and chemotherapeutic actions of polyphenols and related phenolics have received considerable attention since these compounds induce apoptosis in several types of cancer cells in vitro. A plausible criterion for the use of such compounds is that they should not exert any toxic effect on normal cells. However, information about the toxicity of polyphenols and related phenolics to normal cells is limited.