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1.
Gabriel A. Kurokawa Pedro T. Hamamoto Filho Jeany Delafiori Aline F. Galvani Arthur N. de Oliveira Flvia L. Dias-Audibert Rodrigo R. Catharino Maria Inês M. C. Pardini Marco A. Zanini Estela de O. Lima Adriana C. Ferrasi 《International journal of molecular sciences》2023,24(1)
Meningiomas (MGMs) are currently classified into grades I, II, and III. High-grade tumors are correlated with decreased survival rates and increased recurrence rates. The current grading classification is based on histological criteria and determined only after surgical tumor sampling. This study aimed to identify plasma metabolic alterations in meningiomas of different grades, which would aid surgeons in predefining the ideal surgical strategy. Plasma samples were collected from 51 patients with meningioma and classified into low-grade (LG) (grade I; n = 43), and high-grade (HG) samples (grade II, n = 5; grade III, n = 3). An untargeted metabolomic approach was used to analyze plasma metabolites. Statistical analyses were performed to select differential biomarkers among HG and LG groups. Metabolites were identified using tandem mass spectrometry along with database verification. Five and four differential biomarkers were identified for HG and LG meningiomas, respectively. To evaluate the potential of HG MGM metabolites to differentiate between HG and LG tumors, a receiving operating characteristic curve was constructed, which revealed an area under the curve of 95.7%. This indicates that the five HG MGM metabolites represent metabolic alterations that can differentiate between LG and HG meningiomas. These metabolites may indicate tumor grade even before the appearance of histological features. 相似文献
2.
Lipid metabolism was studied in rats fed diets containing corn oil, coconut oil, or medium-chain triglyceride (MCT), a glyceride
mixture containing fatty acids of 8 and 10 carbons in length. The ingestion of MCT-supplemented, cholesterolfree diets depressed
plasma and liver total lipids and cholesterol as compared with corn oil-supplemented diets. In rats fed cholesterol-containing
diets, plasma cholesterol levels were not influenced by dietary MCT, but liver cholesterol levels were significantly lower
than in animals fed corn oil. In vitro cholesterol synthesis from acetate-1-14C was lower in liver slices of rats that consumed MCT than in similar preparations from corn oil-fed rats. Studies of fatty
acid carboxyl labeling from acetate-1-14C and the conversion of palmitate-1-14C to C18 acids by liver slices showed that chain-lengthening activity is greater in the liver tissue of rats fed MCT than in the liver
of animals fed corn oil. The hepatic fatty acid desaturation mechanisms, evaluated by measuring the conversion of stearate-2-14C to oleate, was also enhanced by feeding MCT.
Adipose tissue of rats fed MCT converts acetate-1-14C to fatty acids at a much faster rate than does tissue from animals fed corn oil. Evidence is presented to show that the
enhanced incorporation of acetate into fatty acids by the adipose tissue of rats fed MCT represents de novo synthesis of fatty
acids and not chain-lengthening activity. Data are also presented on the fatty acid composition of plasma, liver, and adipose
tissue lipids of rats fed the different fats under study. 相似文献
3.
Effect of competitive ions on the arsenic removal by mesoporous hydrous zirconium oxide from drinking water 总被引:1,自引:0,他引:1
Adsorption properties of 302-type commercially available hydrous zirconium oxide (302-HZO) towards arsenic and some competitive anions and cations have been studied under batch and column conditions. Due to amphoteric properties, anion exchange performance of hydrous zirconium oxide is pH dependent. Media exhibits high affinity towards arsenic in a broad pH range, with high adsorption capacity at pH < 8. It was shown that silicate and phosphate ions are arsenic's main competitors affecting media adsorption capacity. Presence of transition metal cations in <1 ppm does not affect 302-HZO capacity on arsenic, whereas alkaline-earth cations improve arsenic removal. The possibility for significant increase of 302-HZO adsorption capacity on arsenic at pH > 8 by using “solid acidifier” technique is discussed. Results of 302-HZO field trials are presented. 相似文献
4.
Roberto Barbuti Andrea Maggiolo-Schettini Paolo Milazzo Giovanni Pardini Luca Tesei 《Natural computing》2011,10(1):3-16
We present Spatial P systems, a variant of P systems which embodies the concept of space and position inside a membrane. Objects
in membranes are associated with positions. Rules specify, in the usual way, the objects which are consumed and the ones which
are produced; in addition, they can specify the positions of the produced objects. Objects belong to two different sets: the
set of ordinary objects and the set of mutually exclusive objects. Every position inside a membrane can accommodate an arbitrary number of ordinary objects, but at most one mutually
exclusive object. We prove that Spatial P systems are universal even if only non-cooperating rules are allowed. We also show
how Spatial P systems can be used to model the evolution of populations in presence of geographical separations. 相似文献
5.
Synthesis and characterization of a mesoporous hydrous zirconium oxide used for arsenic removal from drinking water 总被引:1,自引:0,他引:1
Powder (20-50 μm) mesoporous hydrous zirconium oxide was prepared from a zirconium salt granular precursor. The effect of some process parameters on product morphology, porous structure and adsorption performance has been studied. The use of hydrous zirconium oxide for selective arsenic removal from drinking water is discussed. 相似文献
6.
Burke Jeffrey D.; Loeber Rolf; White Helene Raskin; Stouthamer-Loeber Magda; Pardini Dustin A. 《Canadian Metallurgical Quarterly》2007,116(2):249
The authors examined the prediction from inattention to tobacco use among 2 cohorts (ages 7 and 13) of a community sample followed to young adulthood. Changes in self-reported tobacco use were tested with marginal transitional regression models, using parent and teacher ratings of inattention, hyperactivity-impulsivity, and other psychopathology, along with other factors, as predictors. Inattention, but not hyperactivity-impulsivity, significantly predicted adolescent tobacco use and young adult daily tobacco use. Peer substance use, parental substance use, and conduct disorder also predicted increases in tobacco use. African American ethnicity was strongly protective against later tobacco use. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
7.
E.?C.?BotelhoEmail author M.?L.?Costa L.?C.?Pardini M.?C.?Rezende 《Journal of Materials Science》2005,40(14):3615-3623
Fiber reinforced epoxy composites are used in a wide variety of applications in the aerospace field. These materials have high specific moduli, high specific strength and their properties can be tailored to application requirements. In order to screening optimum materials behavior, the effects of external environments on the mechanical properties during usage must be clearly understood. The environmental action, such as high moisture concentration, high temperatures, corrosive fluids or ultraviolet radiation (UV), can affect the performance of advanced composites during service. These factors can limit the applications of composites by deteriorating the mechanical properties over a period of time. Properties determination is attributed to the chemical and/or physical damages caused in the polymer matrix, loss of adhesion of fiber/resin interface, and/or reduction of fiber strength and stiffness. The dynamic elastic properties are important characteristics of glass fiber reinforced composites (GRFC). They control the damping behavior of composite structures and are also an ideal tool for monitoring the development of GFRC’s mechanical properties during their processing or service. One of the most used tests is the vibration damping. In this work, the measurement consisted of recording the vibration decay of a rectangular plate excited by a controlled mechanism to identify the elastic and damping properties of the material under test. The frequency amplitude were measured by accelerometers and calculated by using a digital method. The present studies have been performed to explore relations between the dynamic mechanical properties, damping test and the influence of high moisture concentration of glass fiber reinforced composites (plain weave). The results show that the E’ decreased with the increase in the exposed time for glass fiber/epoxy composites specimens exposed at 80∘C and 90% RH. The E’ values found were: 26.7, 26.7, 25.4, 24.7 and 24.7 GPa for 0, 15, 30, 45 and 60 days of exposure, respectively. 相似文献
8.
Dietary menhaden oil enhances mitomycin C antitumor activity toward human mammary carcinoma MX-1 总被引:3,自引:0,他引:3
In the present study, we investigated the effects of high levels of dietary fish oil on the growth of MX-1 human mammary carcinoma
and its response to mitomycin C (MC) treatment in athymic mice. We found that high levels of dietary fish oil (20% menhaden
oil+5% corn oil, w/w) compared to a control diet (5% corn oil, w/w) not only lowered the tumor growth rate, but also increased
the tumor response to MC treatment. We also found that high levels of dietary fish oil significantly increased the activities
of tumor xanthine oxidase and DT-diaphorase, which are proposed to be involved in the bioreductive activation of MC. Since
menhaden oil is highly unsaturated, its intake caused a significant increase in the degree of fatty acid unsaturation in tumor
membrane phospholipids. This alteration in tumor membrane phospholipids made the tumor more susceptible to oxidative stress,
as indicated by the increased levels of both endogenous lipid peroxidation and protein oxidation after feeding the host animals
the menhaden oil diet. In addition, the tumor antioxidant enzyme activities, catalase (CAT), superoxide dismutase (SOD), glutathione
peroxidase (GPOx), and glutathione S-transferase peroxidase (GSTPx), were all significantly enhanced by feeding a diet high
in fish oil. MC treatment caused further increases in tumor lipid peroxidation and protein oxidation, as well as in the activities
of CAT, SOD, GPOx, and GSTPx, suggesting that MC causes oxidative stress in this tumor model which is exacerbated by feeding
a diet high in menhaden oil. Thus, feeding a diet rich in menhaden oil decreased the growth of human mammary carcinoma MX-1,
increased its responsiveness to MC, and increased its susceptibility to endogenous and MC-induced oxidative stress, and increased
the tumor activities of two enzymes proposed to be involved in the bioactivation of MC, that is, DT-diaphorase and xanthine
oxidase. These findings support a role of these two enzymes in the bioactivating of MC and indicate that the type of dietary
fat may be important in tumor response to therapy. 相似文献
9.
R. S. Almeida C. A. Damato E. C. Botelho L. C. Pardini M. C. Rezende 《Journal of Materials Science》2008,43(9):3173-3179
The tension–tension fatigue behavior of metal/fiber laminates (MFLs) has been investigated. These MFLs were produced with
carbon fiber and by treating the aluminum foil to promote adhesion bonding by two methods: sulfuric–boric–oxalic acid anodization
(SBOA) and chromic acid anodization (CAA). The surface treatments were evaluated by scanning electron microscopy (SEM) techniques
and roughness measurements. It was observed that MFL specimens produced with SBOA treatments presents comparable mechanical
results when compared with MFLs produced with CAA treatment. Microstructural observations of the fracture surfaces by SEM
show hackle formation is the predominant damage mechanism. 相似文献
10.
Lombardini F. Pardini M. Fornaro G. Serafino F. Verrazzani L. Costantini M. 《Radar, Sonar & Navigation, IET》2009,3(4):424-436
Three-dimensional (3-D) synthetic aperture radar (SAR) imaging is a recent technique, based on coherent SAR data combination, and aims to obtain a full 3-D analysis in space. It is a multibaseline extension of the SAR interferometry concept and offers new options for the analysis and monitoring of ground scenes by means of the capability of separating the scattering phenomena along the height dimension. In this work, the authors summarise and extend the results obtained by processing real ERS satellite urban data characterised by a long time span of acquisition and non-uniformly spaced satellite passes, comparing the performance in height focusing obtained with a singular value decomposition (SVD)-based method and adaptive beamforming. 相似文献