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311.
Tryba B 《Journal of hazardous materials》2008,151(2-3):623-627
TiO2 and Fe-C-TiO2 photocatalysts have been immobilized on the cotton material and used in a flow photocatalytic reactor for phenol decomposition. The cotton material has been applied as a support for photocatalyst, because can be easily removed and replaced in a reactor, what facilitates the performance of the photocatalytic process. Fe-C-TiO2 photocatalyst has been prepared by modification of TiO2 fine particles of anatase structure with FeC2O4 through heating in Ar at 500 degrees C. The immobilized photocatalysts could efficiently decompose phenol in multiple use, Fe-C-TiO2 showed higher photocatalytic activity than TiO2, around 15-18 mg and 15-16 mg of phenol have been decomposed after 5 h of UV irradiation on Fe-C-TiO2 and TiO2, respectively. After addition of H2O2 the phenol decomposition and the mineralization degree have been accelerated, especially with immobilized Fe-C-TiO2 photocatalyst, in case of that the photo-Fenton reaction occurred. In the presence of H2O2 around 26-28 mg and 21-24 mg of phenol have been decomposed on Fe-C-TiO2 and TiO2 respectively, after 5 h of UV irradiation. 相似文献
312.
Jastrzebska M Mróz I Barwiński B Zalewska-Rejdak J Turek A Cwalina B 《Journal of materials science. Materials in medicine》2008,19(1):249-256
Pericardial tissue (bovine or porcine), chemically stabilized with glutaraldehyde (GA), is widely used in cardiovascular surgery
in the form of bioprosthetic valves. GA reacts with tissue proteins and creates inter- and intra-molecular cross-links, resulting
in improved durability. However, tissue calcification and mechanical damage are still unresolved problems. The purpose of
this study was to examine the surface topography of normal human aortic valve and GA-stabilized porcine pericardium tissue
in order to gain comparative insight into supramolecular structure of both tissues. The analysis was focused on morphologic
evaluation of collagen constituents of the tissues. Atomic force microscopy working in the contact mode in air was employed
in the study. Considerable diversity in the spatial orientation of collagen fibrils for the human aortic valve and pericardial
tissue were observed. It was found that different forms of collagen fibril packing, i.e. dense and “in phase” or loose, could
have an impact on the collagen D-banding pattern. Stabilization with GA introduced significant changes in the surface topography
of collagen fibrils and in their spatial organization on the tissue surface. Strong disturbance in the fibril’s D-spacing
was observed. It was also suggested, that the observed structural changes at the supramolecular level might make an important
contribution to the progressive damage and calcification of the tissue. The presented results demonstrate that the AFM method
can be useful for non-destructive structural characterization of heart valves and bioprosthetic heart valve material. 相似文献
313.
Flow injection high field asymmetric waveform ion mobility spectrometry (FAIMS)-mass spectrometry (MS) methodology was developed for the detection and identification of chemical warfare (CW) agents in spiked food products. The CW agents, soman (GD), sarin (GB), tabun (GA), cyclohexyl sarin (GF), and four hydrolysis products, ethylphosphonic acid (EPA), methylphosphonic acid (MPA), pinacolyl methylphosphonic acid (Pin MPA), and isopropyl methylphosphonic acid (IMPA) were separated and detected by positive ion and negative ion atmospheric pressure ionization-FAIMS-MS. Under optimized conditions, the compensation voltages were 7.2 V for GD, 8.0 V for GA, 7.2 V for GF, 7.6 V for GB, 18.2 V for EPA, 25.9 V for MPA, -1.9 V for PinMPA, and +6.8 V for IMPA. Sample preparation was kept to a minimum, resulting in analysis times of 3 min or less per sample. The developed methodology was evaluated by spiking bottled water, canola oil, cornmeal, and honey samples at low microgram per gram (or microg/mL) levels with the CW agents or CW agent hydrolysis products. The detection limits observed for the CW agents in the spiked food samples ranged from 3 to 15 ng/mL in bottled water, 1-33 ng/mL in canola oil, 1-34 ng/g in cornmeal, and 13-18 ng/g in honey. Detection limits were much higher for the CW agent hydrolysis products, with only MPA being detected in spiked honey samples. 相似文献
314.
Czarnecka B Deregowska-Nosowicz P Limanowska-Shaw H Nicholson JW 《Journal of materials science. Materials in medicine》2007,18(5):845-849
Summary The aim of this study was determine whether bonding of glass-ionomer cements to non-carious dentine differed from that to
carious dentine. Five commercial cements were used, namely Fuji IX GP, Fuji IX capsulated, Fuji IX Fast capsulated (all GC,
Japan), Ketac-Molar and Ketac-Molar Aplicap (both 3M-ESPE, Germany). Following conditioning of the substrate with 10% poly
(acrylic acid) for 10 s, sets of 10 samples of the cements were bonded to prepared teeth that had been removed for orthodontic
reasons. The teeth used had either sound dentine or sclerotic dentine. Shear bond strengths were determined following 24 h
storage. For the auto-mixed cements, shear bond strength to sound dentine was found not to differ statistically from shear
bond strength to sclerotic dentine whereas for hand-mixed cements, shear bond to sound dentine was found to be higher than
to carious dentine (to at least p < 0.05). This shows that the chemical effects arising from interactions of glass-ionomer cements with the mineral phase of
the tooth are the most important in developing strong bonds, at least in the shorter term. 相似文献
315.
Anna Gluba-Brzzka Beata Franczyk Magdalena Rysz-Grzyska Robert Rokicki Magorzata Koziarska-Rociszewska Jacek Rysz 《International journal of molecular sciences》2021,22(18)
Thalassemia, a chronic disease with chronic anemia, is caused by mutations in the β-globin gene, leading to reduced levels or complete deficiency of β-globin chain synthesis. Patients with β-thalassemia display variable clinical severity which ranges from asymptomatic features to severe transfusion-dependent anemia and complications in multiple organs. They not only are at increased risk of blood-borne infections resulting from multiple transfusions, but they also show enhanced susceptibility to infections as a consequence of coexistent immune deficiency. Enhanced susceptibility to infections in β-thalassemia patients is associated with the interplay of several complex biological processes. β-thalassemia-related abnormalities of the innate immune system include decreased levels of complement, properdin, and lysozyme, reduced absorption and phagocytic ability of polymorphonuclear neutrophils, disturbed chemotaxis, and altered intracellular metabolism processes. According to available literature data, immunological abnormalities observed in patients with thalassemia can be caused by both the disease itself as well as therapies. The most important factors promoting such alterations involve iron overload, phenotypical and functional abnormalities of immune system cells resulting from chronic inflammation oxidative stress, multiple blood transfusion, iron chelation therapy, and splenectomy. Unravelling the mechanisms underlying immune deficiency in β-thalassemia patients may enable the designing of appropriate therapies for this group of patients. 相似文献
316.
317.
Effect of supplementation of cows diet with linseed and fish oil and different variants of β‐lactoglobulin on fatty acid composition and antioxidant capacity of milk
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318.
Damila M. Bogusawska Micha Skulski Beata Machnicka Stanisaw Potoczek Sebastian Kraszewski Kazimierz Kuliczkowski Aleksander F. Sikorski 《International journal of molecular sciences》2021,22(20)
Hereditary spherocytosis (HS), the most commonly inherited hemolytic anemia in northern Europeans, comprises a group of diseases whose heterogeneous genetic basis results in a variable clinical presentation. High-throughput genome sequencing methods have made a leading contribution to the recent progress in research on and diagnostics of inherited diseases and inspired us to apply whole exome sequencing (WES) to identify potential mutations in HS. The data presented here reveal a novel mutation probably responsible for HS in a single Polish family. Patients with clinical evidence of HS (clinical symptoms, hematological data, and EMA test) were enrolled in the study. The examination of the resulting WES data showed a number of polymorphisms in 71 genes associated with known erythrocyte pathologies (including membranopathies, enzymopathies, and hemoglobinopathies). Only a single SPTB gene variant indicated the possible molecular mechanism of the disease in the studied family. The new missense mutation p.C183Y was identified using WES in the SPTB gene, which is most likely the cause of clinical symptoms typical of hereditary spherocytosis (membranopathy) due to structural and functional impairments of human β-spectrin. This mutation allows for a better understanding of the molecular mechanism(s) of one of the membranopathies, hereditary spherocytosis. 相似文献
319.
Beata Dbrowska-Bouta Lidia Struyska Marta Sidoryk-Wgrzynowicz Grzegorz Sulkowski 《International journal of molecular sciences》2021,22(21)
Experimental autoimmune encephalomyelitis (EAE) is an animal model most commonly used in research on the pathomechanisms of multiple sclerosis (MS). The inflammatory processes, glutamate excitotoxicity, and oxidative stress have been proposed as determinants accompanying demyelination and neuronal degeneration during the course of MS/EAE. The aim of the current study was to characterize the role of NMDA receptors in the induction of oxidative stress during the course of EAE. The effect of memantine, the uncompetitive NMDA receptor antagonist, on modulation of neurological deficits and oxidative stress in EAE rats was analyzed using several experimental approaches. We demonstrated that the expression of antioxidative enzymes (superoxide dismutases SOD1 and SOD2) were elevated in EAE rat brains. Under the same experimental conditions, we observed alterations in oxidative stress markers such as increased levels of malondialdehyde (MDA) and decreased levels of sulfhydryl (-SH) groups, both protein and non-protein (indicating protein damage), and a decline in reduced glutathione. Importantly, pharmacological inhibition of ionotropic NMDA glutamate receptors by their antagonist memantine improved the physical activity of EAE rats, alleviated neurological deficits such as paralysis of tail and hind limbs, and modulated oxidative stress parameters (MDA, -SH groups, SOD’s). Furthermore, the current therapy aiming to suppress NMDAR-induced oxidative stress was partially effective when NMDAR’s antagonist was administered at an early (asymptomatic) stage of EAE. 相似文献
320.
Aleksandra Rapacka-Zdonczyk Agata Wozniak Beata Kruszewska Krzysztof Waleron Mariusz Grinholc 《International journal of molecular sciences》2021,22(21)
Antimicrobial blue light (aBL) treatment is considered low risk for the development of bacterial resistance and tolerance due to its multitarget mode of action. The aim of the current study was to demonstrate whether tolerance development occurs in Gram-negative bacteria. We evaluated the potential of tolerance/resistance development in Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa and demonstrated that representative Gram-negative bacteria may develop tolerance to aBL. The observed adaption was a stable feature. Assays involving E. coli K-12 tolC-, tolA-, umuD-, and recA-deficient mutants revealed some possible mechanisms for aBL tolerance development. 相似文献