Synthesis of thin titania coatings onto the inner surface of quartz tubes and their photoactivity in decomposition of methylene blue and rhodamine B

An evaporation-deposition coating method for coating the inner surface of long (>1 m) quartz tubes of small diameter has been studied by the introduction of two-phase (gas-liquid) flow with the gas core flowing in the middle and a thin liquid film of synthesis sol flowing near the hot tube wall. The operational window for the deposition of continuous titania coatings has been obtained. The temperature range for the deposition of continuous titania coatings is limited to 105–120 °C and the gas flow rate is limited to the range of 0.4–1.0 L min−1. The liquid flow rate in the annular flow regime allows to control the coating thickness between 3 and 10 micron and the coating porosity between 10% and 20%. By increasing the liquid flow rate, the coating porosity can be substantially reduced. The coatings were characterized by X-ray diffraction, N2 chemisorption, thermogravimetric analysis, and scanning electron microscopy. The coatings were tested in the photocatalytic decomposition of methylene blue and rhodamine B under UV-light and their activity was similar to that of a commercial P25 titania catalyst

Blast Brain Injury Elevates Catecholamine Biosynthesis in the Nucleus Tractus Solitaries and Oxidative Stress in the Hypothalamus in Rats

Introduction: Traumatic Brain Injury (TBI) produces major health problems impacting the lives of both military and civilian personnel. TBI disrupts autonomic function but the nature of this disruption is unknown. Following blast brain injury, we assessed selective biochemical markers for autonomic function in adult male Sprague Dawley rats. Methods: Rats were subjected to head-directed overpressure blast injury (OBI) of 358 kPa magnitude at the target. At the same time for sham controls, rats were anesthetized as the previous group but instead of OBI were exposed just to noise being placed at ~ 2 m distance from the shock tube nozzle. Sympathetic nervous system activation of nucleus tractus solitaries and in the hypothalamus was evaluated at 6 hours following blast injury by assessing the expression of catecholamine biosynthesizing enzyme, tyrosine hydroxylase (TH) in the nucleus tractus solitaries and NADPH oxidase activity, a marker of oxidative stress,in the hypothalamus. Results: Following OBI there was a significant elevation in TH protein expression by 49% compared with control (P\u3c0.05). In addition, NADPH oxidase activity was significantly increased by 36% following OBI (P\u3c0.05). Conclusions: Collectively, the increased catecholamine biosynthesis in nucleus tractus solitaries and oxidative stress in the hypotalamus suggest that OBI results in increased sympathoexcitation in the rat brain. Such effects may be one important factor contributing to autonomic dysfunction following OBI. Acknowledgements: Supported by Department of Veteran Affairs; Rehabilitation R&D, GRECC, Medical Research Services, Banyan Biomarkers Inc, University of Florida Brain Institute, NIA, and AH

Argininosuccinate synthetase as a plasma biomarker of liver injury after acetaminophen overdose in rodents and humans

Context: New biomarkers are needed in acetaminophen (APAP) hepatotoxicity. Plasma argininosuccinate synthetase (ASS) is a promising candidate. Objective: Characterize ASS in APAP hepatotoxicity. Methods: ASS was measured in plasma from rodents and humans with APAP hepatotoxicity. Results: In mice, ASS increased before injury, peaked before alanine aminotransferase (ALT) and decreased rapidly. Fischer rats had a greater increase in ASS relative to ALT. Patients with abnormal liver test results had very high ASS compared to controls. ASS appeared to increase early in some patients, and declined rapidly in all. Conclusions: ASS may be a useful biomarker of acute cell death in APAP hepatotoxicity. © 2014 Informa UK Ltd. All rights reserved: reproduction in whole or part not permitted

Hepatic oval (stem) cell expression of endothelial differentiation gene receptors for lysophosphatidic acid in mouse chronic liver injury.

Growth factor lysophosphatidic acid (LPA) regulates cell proliferation and differentiation and increases motility and survival in several cell types, mostly via G-protein-coupled receptors encoded by endothelial differentiation genes (EDG). We show herein that hepatic oval (stem) cell proliferation, induced by 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) in a mouse model of chronic liver injury, was associated with the expression of LPA1, LPA2, and LPA3 receptor subtypes; only LPA1 receptor protein was detectable in normal liver by western blot. In the injured liver, enhanced LPA1 receptor was identified predominantly in oval cells along the portal tract, proliferating ductular epithelial cells, and small cells, which were located in the nearby parenchyma and formed clusters. Interestingly, the LPA1 receptor was co-expressed in DDC-treated livers with the stem cell antigen SCA-1, suggesting that this receptor may be associated with bone marrow-derived progenitors. All three receptors for LPA were detected mostly in small cells in the vicinity of the portal tract, and co-localized with the A6 antigen, a marker of ductular oval cells. In addition, hepatic levels of endogenous LPA were significantly higher in DDC-fed mice compared to normal animals. We propose that the expression of diverse LPA receptors may be a necessary part of the mechanism responsible for activation of oval cells during liver injury. As a result, LPA and its analogs may represent critical endogenous mediators, which regulate survival, increase motility, and modulate proliferation and differentiation of hepatocyte progenitors in regenerating liver