scholarly journals An Essential Role of Polymeric Adhesives in the Reinforcement of Acidified Paper Relics

Polymers ◽  
2022 ◽  
Vol 14 (1) ◽  
pp. 207
Author(s):  
Jiaojiao Liu ◽  
Huiping Xing ◽  
Yajun Zhou ◽  
Xiaolian Chao ◽  
Yuhu Li ◽  
...  

Paper acidification causes paper relics to undergo embrittlement and decay, to form dregs, and even to break upon a single touch; therefore, reinforcement and deacidification treatments are essential steps for paper conservation and to retard the deterioration and prolong the life of objects. Polymeric adhesives play an essential role in reinforcement and deacidification treatments, although it is not well studied. In this work, the effect of polymeric adhesives on the conservation process and their protective effects on acidified paper relics were studied. Firstly, three polymeric adhesives, including wheat starch paste, polyvinyl butyral (PVB), and polyvinyl alcohol (PVA), were selected as research objects. Subsequently, their effects on four popular conservation methods were further discussed, including traditional mounting, hot-melt with silk net, alcohol-soluble cotton mesh, and water-soluble cotton mesh. Additionally, as an example, the reversibility and long-term durability of water-soluble adhesive PVA-217 were assessed. Using a computer measured and controlled folding endurance tester, pendulum tensile strength tester, tear tester, burst tester, FT-IR, video optical contact angle tester, and other instruments, the conservation application of water-soluble adhesives in paper relics was evaluated. This study provides a scientific basis and experimental data for the application of polymeric adhesives in the conservation of paper relics.

1999 ◽  
Vol 14 (4) ◽  
pp. 491-522
Author(s):  
Brady Coleman ◽  
Robert Beckman

AbstractIntegrated coastal management (ICM) programmes are being planned, formulated and implemented in coastal States all over the world. To date, however, ICM has been seen as more in the realm of policy-makers, managers, scientists, coastal resource economists, and others, rather than in the realm of lawyers. This article reveals how law and lawyers should play an absolutely essential role at all stages of the ICM process. Ideally, ICM legal consultants will have a broad range of knowledge and experience in both international legal treaties as well as in certain fundamental national law principles, so that coastal zone policies will be designed and carried out with a critical understanding of the laws and institutions needed for the long-term success of an integrated coastal management programme.


2006 ◽  
Vol 20 (4) ◽  
pp. 795-808 ◽  
Author(s):  
Chung S. Song ◽  
Ibtissam Echchgadda ◽  
Young-Kyo Seo ◽  
Taesung Oh ◽  
Soyoung Kim ◽  
...  

Abstract The vitamin D receptor (VDR) regulates steroid and drug metabolism by inducing the genes encoding phase I and phase II enzymes. SULT2A1 is a liver- and intestine-expressed sulfo-conjugating enzyme that converts the alcohol-OH of neutral steroids, bile acids, and drugs to water-soluble sulfated metabolites. 1α,25-Dihydroxyvitamin D3 [1,25-(OH)2D3] induces SULT2A1 gene transcription after the recruitment of VDR to the vitamin D-responsive chromatin region of SULT2A1. A composite element in human SULT2A1 directs the 1,25-(OH)2D3-mediated induction of natural and heterologous promoters. This element combines a VDR/retinoid X receptor-α-binding site [vitamin D response element (VDRE)], which is an imperfect inverted repeat 2 of AGCTCA, and a CAAT/enhancer binding protein (C/EBP)-binding site located 9 bp downstream to VDRE. The binding sites were identified by EMSA, antibody supershift, and deoxyribonuclease I footprinting. C/EBP-α at the composite element plays an essential role in the VDR regulation of SULT2A1, because 1) induction was lost for promoters with inactivating mutations at the VDRE or C/EBP element; 2) SULT2A1 induction by 1,25-(OH)2D3 in C/EBP-α-deficient cells required the expression of cotransfected C/EBP-α; and 3) C/EBP-β did not substitute for C/EBP-α in this regulation. VDR and C/EBP-α were recruited concurrently to the composite element along with the coactivators p300, steroid receptor coactivator 1 (SRC-1), and SRC-2, but not SRC-3. VDR and C/EBP-α associated endogenously as a DNA-dependent, coimmunoprecipitable complex, which was detected at a markedly higher level in 1,25-(OH)2D3-treated cells. These results provide the first example of the essential role of the interaction in cis between C/EBP-α and VDR in directing 1,25-(OH)2D3-induced expression of a VDR target gene.


2020 ◽  
Author(s):  
Yajing Wang ◽  
Bingxian Liu ◽  
Qingyue Han ◽  
Khalid Mehmood ◽  
Fazul Nabi ◽  
...  

Abstract Background: Fluorine is widespread in the environment, and the injurious impacts of fluoride underscore its significance for public health. The long-term presence of fluorine in environment could be a risk in hepatotoxicity for both human beings and animals. Important role of selenium in mitigation of heavy metal toxicity via regulating autophagy and apoptosis is well-known. Further, nano-Se is a common artificial nano material, with higher biological activity and lower toxicity. The aim of the current study was to examine whether nano-Se supplementation can reduce the effects of fluoride-induced hepatocytes autophagy and apoptosis. Results: Here, we report that fluoride exposure induces apoptosis and autophagy with nucleus broken, dissolved and disappeared of hepatocyte, contributing to its hepatotoxicity. More importantly, Cyt-C and Beclin-1/Bcl-2 pathways are involved in the regulation of autophagy and apoptosis via targeting Caspase-9, Caspase-3, P53, Bax, LC3, ATG-5, P62 and mTOR expressions. Conclusion: Nano-Se is capable to alleviate fluoride-induced hepatocyte damage, that selenium can be prefer to prevent chronic fluorosis-induced autophagy and apoptosis by regulating Cyt-C and Beclin-1/Bcl-2 signaling pathway. In precisely, NaF-induced the liver injury by activating autophagy and apoptosis, which indicate that fluorine exposure, pose an ecological risk to human beings and animals. Nano-Se has protective effects against fluoride-induced hepatocytes.


2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
H. M. Semchyshyn

There is compelling evidence that long-term intake of excessive fructose can have deleterious side effects in different experimental models. However, the role of fructosein vivoremains controversial, since acute temporary application of fructose is found to protect yeast as well as animal tissues against exogenous oxidative stress. This review suggests the involvement of reactive carbonyl and oxygen species in both the cytotoxic and defensive effects of fructose. Potential mechanisms of the generation of reactive species by fructose in the nonenzymatic reactions, their implication in the detrimental and protective effects of fructose are discussed.


1991 ◽  
Vol 36 (2) ◽  
pp. 85-92
Author(s):  
Bruce F. Miller ◽  
William Root

Pharmaceutics ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 745
Author(s):  
Ji Yeon Park ◽  
Dong Ho Oh ◽  
Sang-Wook Park ◽  
Bo Ram Chae ◽  
Chul Woo Kim ◽  
...  

Pelubiprofen (PEL), which is a commercialized non-steroidal anti-inflammatory drug (NSAID), is associated with the risk of gastrointestinal (GI) adverse events following long-term exposure and has poor water-soluble properties. Here, a new pelubiprofen tromethamine (PEL-T) with improved solubility, permeability, GI safety, and absorption, compared to PEL, has been developed. The nuclear magnetic resonance spectroscopy (NMR), differential scanning calorimetry (DSC), and Fourier transform infrared spectroscopy (FT-IR) results confirmed that the PEL-T was well formed. The powder of PEL-T showed the presence of additional 6H protons at δ 3.66–3.61 in the 1H NMR spectrum, and shifted the sharp endothermic peaks at 129 °C in DSC, and the spectrum of distinct absorption peaks in FT-IR. In addition, compared with PEL, PEL-T showed a significantly improved solubility in various media and an increased permeability coefficient (Kp) in Caco-2 cells. Furthermore, compared to PEL oral administration, PEL-T was found to significantly reduce the damaged area in an acute gastric damage rat model. The pharmacokinetic study of the PEL-T powder showed higher maximum plasma concentration (Cmax) and area under the plasma concentration–time curve from 0 h to the last time point (AUCt) than those of the PEL powder. Taken together, our data suggest that PEL-T is a recommendable candidate with enhanced gastrointestinal safety and better absorption compared with commercial PEL.


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