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961.
Michaela Kohlov Susana Rocha Clia Gomes Amorim Alberto de Nova Araújo Alice Santos‐Silva Petr Solich Maria Conceio Branco da Silva Montenegro 《Macromolecular bioscience》2020,20(7)
The reduction of free radicals by bioactive membranes used for hemodialysis treatment is an important topic due to the constant rise of oxidative stress‐associated cardiovascular mortality by hemodialysis patients. Therefore, it is urgent to find an effective solution that helps to solve this problem. Polysulfone membranes enriched with α‐lipoic acid, α‐tocopherol, and with both components are fabricated by spin coating. The antioxidant properties of these membranes are evaluated in vitro by determining the lipid‐peroxidation level and the total antioxidant status of the blood plasma. The biocompatibility is assessed by quantifying the protein adsorption, platelet adhesion, complement activation, and hemolytic effect. All types of membranes show in vitro antioxidant activity and a trend to reduce oxidative stress in vivo; the best results show membranes prepared with a combination of both compounds and prove to be nonhemolytic and hemocompatible. Moreover, the membrane specific separation ability for the main waste products is not affected by antioxidants incorporation. 相似文献
962.
963.
Sayonara Maria Calado Gonçalves Glória Najara Silva Ivan da Rocha Pitta Moacyr Jesus Barreto de Melo Rêgo Simone Cristina Baggio Gnoato 《Natural product research》2020,34(12):1702-1711
AbstractBetulin (BE) is a pentacyclic triterpenes, obtained from natural sources and with several biological activities described, such as anti-tumoral and anti-inflammatory activities. The BE esterification at hydroxyl group (C-3 and C-28) resulted in five new ester derivatives with different numbers of carbons or halogens (chlorine and fluorine). Among these BE derivatives, two (2a e 2c) were able to significantly decrease IFN-g (*p?=?0.0391; **p?=?0.0156) and 2c modulated the expression of COX-2 better than Dexamethasone (DEXA). Regarding to cytotoxic assay, the best results were obtained for BE without modifications, with emphasis on tumoral cell lines Raji and MCF-7. The derivatives 2a and 2c showed immunomodulation activity (for the cytokines IFN-g). The presence of chorine in BE seems to be important for the ability of modulate COX-2 expression, since the ester chloride derivative 2c at 100?μM is more powerful inhibitor of COX-2 than DEXA. 相似文献
964.
Luisa Pieroni Federica Iavarone Alessandra Olianas Viviana Greco Claudia Desiderio Claudia Martelli Barbara Manconi Maria Teresa Sanna Irene Messana Massimo Castagnola Tiziana Cabras 《Journal of separation science》2020,43(1):313-336
More than 300 different protein post‐translational modifications are currently known, but only a few have been extensively investigated because modified proteoforms are commonly present in sub‐stoichiometry amount. For this reason, improvement of specific enrichment techniques is particularly useful for the proteomic characterization of post‐translationally modified proteins. Enrichment proteomic strategies could help the researcher in the challenging issue to decipher the complex molecular cross‐talk existing between the different factors influencing the cellular pathways. In this review the state of art of the platforms applied for the enrichment of specific and most common post‐translational modifications, such as glycosylation and glycation, phosphorylation, sulfation, redox modifications (i.e. sulfydration and nitrosylation), methylation, acetylation, and ubiquitinylation, are described. Enrichments strategies applied to characterize less studied post‐translational modifications are also briefly discussed. 相似文献
965.
966.
Li-Bo Huang Maria Di Vincenzo Dr. Yuhao Li Dr. Mihail Barboiu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(7):2224-2239
Natural Aquaporin (AQP) channels are efficient water translocating proteins, rejecting ions. Inspired by this masterpiece of nature, Artificial Water Channels (AWCs) with controlled functional structures, can be potentially used to mimic the AQPs to a certain extent, offering flexible avenues toward biomimetic membranes for water purification. The objective of this paper is to trace the historical development and significant advancements of current reported AWCs. Meanwhile, we attempt to reveal important structural insights and supramolecular self-assembly principles governing the selective water transport mechanisms, toward innovative AWC-based biomimetic membranes for desalination. 相似文献
967.
Marco Angelucci Pierluigi Gargiani Carlo Mariani Maria Grazia Betti 《Journal of nanoparticle research》2011,13(11):5967-5973
Iron-Phthalocyanine molecules deposited on the Cu(119) vicinal surface form molecular chains along the vicinal surface steps,
as deduced by the low-energy electron diffraction (LEED) reconstruction pattern. The work-function lowers at the FePc single-layer
completion, due to the formation of an interface dipole. Further FePc deposition induces a different growth morphology, as
suggested by the slope discontinuity in the work function variation. Upon depositing potassium onto the FePc thin-film prepared
on Cu(119), the K-injected electrons fill up the Fe-d-associated and ligand-π-related orbitals, as observed by means of high-resolution
ultraviolet photoelectron spectroscopy. 相似文献
968.
Vivian?Regina?Trist?o Fernando?Felippe?de?Carvalho Cinthia?Zanini?Gomes Adriana?Regina?Miranda Cíntia?C.?Vequi-Suplicy Maria?Teresa?Lamy Nestor?Schor Maria?Helena?Bellini 《Journal of fluorescence》2010,20(3):665-669
The progression to end-stage renal failure is independent of the initial pathogenic mechanism. Metabolic acidosis is a common
consequence of chronic renal failure that results from inadequate ammonium excretion and decreased tubular bicarbonate reabsorption.
Protoporphyrin IX (PpIX) is the immediate metabolic precursor of the heme molecule. The purpose of this study was to evaluate
the levels of erythrocytes protoporphyrin IX at an animal model during progressive renal disease. A total of 36 eight-week-old
male Wistar rats were divided into six groups: Normal, 4 and 8 weeks after 5/6 nephrectomy (NX). Renal function was evaluated
by creatinine clearance and plasma creatinine levels. The autofluorescence of erythrocytes porphyrin of healthy and NX rats
was analyzed using fluorescence spectroscopy. Emission spectra were obtained by exciting the samples at 405 nm. Significant
differences between normal and NX rats autofluorescence shape occurred in the 600–700 nm spectral region. A correlation was
observed between emission band intensity at 635 nm and progression of renal disease. 相似文献
969.
The purpose of this study was to evaluate the influence of different light sources for in-office bleaching on surface microhardness
of human enamel. One hundred and five blocks of third molars were distributed among seven groups. The facial enamel surface
of each block was polished and baseline Knoop microhardness of enamel was assessed with a load of 25 g for 5 s. Subsequently,
the enamel was treated with 35% hydrogen peroxide bleaching agent and photo-activated with halogen light (group A) during
38 s, LED (group B) during 360 s, and high intensity diode laser (group C) during 4 s. The groups D (38 s), E (360 s), and
F (4 s) were treated with the bleaching agent without photo-activated. The control (group G) was only kept in saliva without
any treatment. Microhardness was reassessed after 1 day of the bleaching treatment, and after 7 and 21 days storage in artificial
saliva. The mean percentage and standard deviation of microhardness in Knoop Hardness Number were: A 97.8 ± 13.1 KHN; B 95.5
± 12.7 KHN; C 84.2 ± 13.6 KHN; D 128.6 ± 20.5 KHN; E 133.9 ± 14.2 KHN; F 123.9 ± 14.2 KHN; G 129.8 ± 18.8 KHN. Statistical
analysis (p < 0.05; Tukey test) showed that microhardness percentage values were significantly lower in the groups irradiated with light
when compared with the non-irradiated groups. Furthermore, the non-irradiated groups showed that saliva was able to enhance
the microhardness during the measurement times. The enamel microhardness was decreased when light sources were used during
the bleaching process and the artificial saliva was able to increase microhardness when no light was used. 相似文献
970.
Induced polarization forward modelling using finite element method and the fractal model 总被引:1,自引:0,他引:1
V.J. da C. Farias C.H. de M. Maranhão B.R.P. da Rocha N. de P.O. de Andrade 《Applied Mathematical Modelling》2010
The modeling of induced polarization data from 2D and 3D geological medium was developed. We applied the finite element method and the fractal model to complex resistivity of rocks as an intrinsic electrical property of geological medium. The LU factorization and pre-conditioned complex bi-conjugated gradient method were applied to solve the complex linear equation system. The modeling implemented in this work was efficient and prompt. In addition, the induced polarization survey using the fractal model as intrinsic property of the medium is a promising method for environmental investigation. 相似文献