339 research outputs found

    Effect of heat treatment on the chemical structure and thermal properties of softwood-derived glycol lignin

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    A large-scale glycol lignin (GL) production process (50 kg wood meal per batch) based on acid-catalyzed polyethylene glycol (PEG) solvolysis of Japanese cedar (JC) was developed at the Forestry and Forest Products Research Institute (FFPRI), Tsukuba, Japan. JC wood meal with various particle size distributions (JC-S < JC-M < JC-L) (average meal size, JC-S (0.4 mm) < JC-M (0.8 mm) < JC-L (1.6 mm)) and liquid PEG with various molecular masses are used as starting materials to produce PEG-modified lignin derivatives, namely, GLs, with various physicochemical and thermal properties. Because GLs are considered a potential feedstock for industrial applications, the effect of heat treatment on GL properties is an important issue for GL-based material production. In this study, GLs obtained from PEG400 solvolysis of JC-S, JC-M, and JC-L were subjected to heating in a constant-temperature drying oven at temperatures ranging from 100 to 220 °C for 1 h. All heat-treated GL series were thermally stable, as determined from the Klason lignin content, TMA, and TGA analyses. SEC analysis suggests the possibility of condensation among lignin fragments during heat treatment. ATR-FTIR spectroscopy, thioacidolysis, and 2D HSQC NMR demonstrated that a structural rearrangement occurs in the heat-treated GL400 samples, in which the content of α–PEG-β–O-4 linkages decreases along with the proportional enrichments of β–5 and β–β linkages, particularly at treatment temperatures above 160 °C

    Intermodal Network Accessibility in Eastern Asia: System Building and Case Studies

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    Building a GIS Platform for the Quantitative Approach to Regional Studies in Northeast Asi

    Supplementation of protein-free diet with whey protein hydrolysates prevents skeletal muscle mass loss in rats

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    AbstractMuscle mass loss is induced by aging, several catabolic diseases, and malnutrition. It is well known that ingestion of whey protein and its hydrolysates (WPH) is effective in stimulating muscle protein synthesis. However, these studies focused on the acute up-regulation of muscle protein synthesis, and few studies have investigated the effect of whey protein and WPH on muscle mass during chronic malnutrition. The aim of the present study was to investigate the effect of 7 days supplementation of whey protein and WPH on muscle reduction in Wistar rats fed a protein-free (PF) diet. Wistar rats were fed either a standard diet (containing 20% protein) or a PF diet during the experimental period. Those fed a PF diet received a dietary supplement containing an amino acid mixture, whey protein, or WPH for 7 days. The weight of the extensor digitorum longus decreased in rats fed a PF diet supplemented with the amino acid mixture or the whey protein. However, this decrease was partially but significantly suppressed in the group fed the WPH supplement. Additionally, administration of WPH induced a postprandial increase in plasma essential amino acids, branched-chain amino acids, and leucine concentration compared with animals fed the amino acid mixture or the whey protein. These results suggest that 7 days supplementation of the diet with WPH suppressed muscle weight loss in rats fed a PF diet

    Characteristics of dissolved organic matter in a water purification plant and distribution pipes

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    Dissolved organic matter (DOM) needs to be characterized todetermine the ability of a water treatment unit to reduce organic matter andits relationship to the levels of chlorine required for disinfection. Weinvestigated water quality parameters, including DOM, in a waterpurification plant and distribution pipes located in central Japan. Thedissolved organic carbon (DOC) concentration decreased from 0.73 mg/Lin raw water to 0.50 mg/L in purified water by conventional treatmentprocesses. The DOC of purified water decreased slightly in the pipesdownstream of the plant. The three-dimensional excitation-emission matrixfluorescence spectra showed some specific peaks for humic-like substancesand protein-like substances in all water samples, and the compositions ofDOM in purified water were close to those in raw water. However, therewas a peak of protein-like substances in purified and returned water, whichwas not observed for raw water. The fluorescence intensities of humic-likesubstances in purified water decreased downstream of the plant, while thefluorescence intensities of protein-like substances increased in the pipes. The measured molecular weight distributions of DOM in water presentedsome specific peaks, and DOM with a smaller molecular weight was noteasily removed by water treatment processes. There were positiverelationships between decreases in the intensities of some peaks andresidual chlorine decay

    Effects of N,N-dimethyldodecylamine-N-oxide on some cellular parameters of rat thymocytes

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    N,N-Dimethyldodecylamine-N-oxide (DDAO) is an amphoteric surfactant used in many detergents for kitchens. In this study, the effects of DDAO (10–100 μM) on cell lethality, intracellular Ca2+ level, intracellular Zn2+ level, and cellular content of nonprotein thiol were examined in mammalian cells (rat thymocytes) to further characterize its cytotoxicity. DDAO at the concentration of 100 μM (22.9 mg/L) slightly, but significantly, increased the parameters described above, and it showed no significant effect at the concentrations of 30 μM (6.87 mg/L) or less. Therefore, it is unlikely that DDAO at environmentally-relevant concentrations (< 10–70 ng/L) exerts toxic actions on wild mammals and humans

    Effect of triclocarban on membrane potential of rat thymocytes : Assessment with bis-(1,3-dibutylbarbituric acid)trimethine oxonol

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    The effect of triclocarban (TCC), an environmental pollutant from household items and health care products, on membrane potential of rat thymocytes was examined by a flow cytometry with a fluorescent probe sensitive to membrane potential, bis-(1,3-dibutylbarbituric acid)trimethine oxonol, because TCC changes intracellular ionic circumstance that may affect the membrane potential. TCC at 0.3 μM or more (up to 3 μM) depolarized the membranes. This TCC-induced phenomenon was against our prediction because TCC increases intracellular Ca2+ concentration that activates Ca2+-dependent K+ channels, resulting in a hyperpolarization. The depolarization was still observed under Ca2+-free condition, but not under Na+-free condition. Furthermore, TCC hyperpolarized the membranes under Ca2+- and Na+-free condition. To see if TCC inhibits Ca2+-dependent hyperpolarization, the effect of A23187, a calcium ionophore, on the membrane potential was examined in the cells treated with TCC. A23187 induced large depolarization in the cells treated with 0.3–3 μM TCC. The A23187-induced depolarization in the presence of TCC was greatly attenuated under Na+-free or Ca2+-free condition whereas A23187 elicited hyperpolarization in the cells treated with 0.3–3 μM TCC under Ca2+- and Na+-free condition. Results suggest that 0.3–3 μM TCC increases membrane permeability of Na+ and Ca2+, resulting in the depolarization. Large depolarization induced by TCC in the presence of external Ca2+ and Na+ may mask the hyperpolarization elicited via the increase in intracellular Ca2+ concentration by TCC. Thus, there is a possibility that TCC depolarizes membranes of lymphocytes, resulting in alteration of cellular functions of lymphocytes

    Minute ampullary carcinoid tumor with lymph node metastases: a case report and review of literature

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    <p>Abstract</p> <p>Background</p> <p>Carcinoid tumors are usually considered to have a low degree of malignancy and show slow progression. One of the factors indicating the malignancy of these tumors is their size, and small ampullary carcinoid tumors have been sometimes treated by endoscopic resection.</p> <p>Case presentation</p> <p>We report a case of a 63-year-old woman with a minute ampullary carcinoid tumor that was 7 mm in diameter, but was associated with 2 peripancreatic lymph node metastases. Mild elevation of liver enzymes was found at her regular medical check-up. Computed tomography (CT) revealed a markedly dilated common bile duct (CBD) and two enlarged peripancreatic lymph nodes. Endoscopy showed that the ampulla was slightly enlarged by a submucosal tumor. The biopsy specimen revealed tumor cells that showed monotonous proliferation suggestive of a carcinoid tumor. She underwent a pylorus-preserving whipple resection with lymph node dissection. The resected lesion was a small submucosal tumor (7 mm in diameter) at the ampulla, with metastasis to 2 peripancreatic lymph nodes, and it was diagnosed as a malignant carcinoid tumor.</p> <p>Conclusion</p> <p>Recently there have been some reports of endoscopic ampullectomy for small carcinoid tumors. However, this case suggests that attention should be paid to the possibility of lymph node metastases as well as that of regional infiltration of the tumor even for minute ampullary carcinoid tumors to provide the best chance for cure.</p
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