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41.
We studied changes in lipid composition of human promyelocytic leukemia cells (HL-60) on differentiation to the macrophage/monocytic
lineage by treatment with the phorbol ester, 12-O-tetradecanoyl-phorbol-13-acetate. Differentiation was accompanied by: (i)
a decrease in the level of phospholipids; (ii) a greater amount of triacylglycerols; (iii) an increase in 1-alk-1′-enyl-2-acyl-
and 1-alkyl-2-acyl-sn-glycero-3-phosphoethanolamine and a decrease in 1-alkyl-2-acyl-sn-glycero-3-phosphocholine; and (iv) an increase in the level of arachidonic acid in ethanolamine phospholipids. The increased
levels of ether-linked lipids and of arachidonic acid in ethanolamine phospholipids are consistent with an enhanced biosynthesis
of platelet-activating factor and eicosanoids, which are particularly important in the macrophage function. 相似文献
42.
43.
Qian Wang Chunfeng Hu Shu Cai Yoshio Sakka Salvatore Grasso Qing Huang 《International Journal of Applied Ceramic Technology》2014,11(5):911-918
High‐purity ternary laminated compound Ti3SiC2 was successfully synthesized by a microwave heating method in the flowing argon for the first time. The mixtures of titanium, silicon, and graphitic carbon (Cgc) or activated carbon (Cac) with different molar ratios were used to investigate the reaction mechanisms. It was confirmed that Ti3SiC2 with high purity of 98 vol.% was achieved without the aids of Al. The optimum experimental parameters were determined as Ti/Si/Cgc having the molar ratio of 3/2.2/2, first holding at 1480°C for 30 min, and subsequent dwelling at 1300°C for 60 min. 相似文献
44.
Lubomír Pospíšil Magdaléna Hromadová Jana Bulí?ková Salvatore Filippone Zhu Guan Yongmin Zhang 《Carbon》2010,48(1):153-1408
The formal redox potentials of electron transfer reactions of fullerene, methanofullerene, fullerene-cyclodextrin complex and methanofullerene conjugates with cyclodextrins in aqueous and dimethylsulfoxide solutions are reported. These new compounds are surface active and retain the redox activity of C60 even in aqueous medium. Compounds have been characterized by an electrochemical admittance technique, which offers an advantage of separating faradaic and capacitive properties. Observed difference of formal redox potentials of the free fullerene forms and their cyclodextrin-containing compounds were used to determine the binding enhancement. Results are interpreted in terms of inter-molecular host-guest interactions of C60-cyclodextrin conjugates. 相似文献
45.
46.
Chiara Maria Motta Emanuela Califano Rosaria Scudiero Bice Avallone Chiara Fogliano Salvatore De Bonis Anja Raggio Palma Simoniello 《International journal of molecular sciences》2022,23(4)
In aquatic organisms, cadmium exposure occurs from ovum to death and the route of absorption is particularly wide, being represented by skin, gills and gastrointestinal tract, through which contaminated water and/or preys are ingested. It is known that cadmium interferes with the gut; however, less information is available on cadmium effects on an important component of the gut, namely goblet cells, specialized in mucus synthesis. In the present work, we studied the effects of two sublethal cadmium concentrations on the gut mucosa of Danio rerio. Particular attention was paid to changes in the distribution of glycan residues, and in metallothionein expression in intestinal cells. The results show that cadmium interferes with gut mucosa and goblet cells features. The effects are dose- and site-dependent, the anterior gut being more markedly affected than the midgut. Cadmium modifies the presence and/or distribution of glycans in the brush border and cytoplasm of enterocytes and in the goblet cells’ cytoplasm and alters the metallothionein expression and localization. The results suggest a significant interference of cadmium with mucosal efficiency, representing a health risk for the organism in direct contact with contamination and indirectly for the trophic chain. 相似文献
47.
Maria Lisa Garavaglia Daniela Giustarini Graziano Colombo Francesco Reggiani Silvia Finazzi Marta Calatroni Lucia Landoni Nicola Marcello Portinaro Aldo Milzani Salvatore Badalamenti Ranieri Rossi Isabella Dalle-Donne 《International journal of molecular sciences》2022,23(5)
Thiols (sulfhydryl groups) are effective antioxidants that can preserve the correct structure of proteins, and can protect cells and tissues from damage induced by oxidative stress. Abnormal levels of thiols have been measured in the blood of patients with moderate-to-severe chronic kidney disease (CKD) compared to healthy subjects, as well as in end-stage renal disease (ESRD) patients on haemodialysis or peritoneal dialysis. The levels of protein thiols (a measure of the endogenous antioxidant capacity inversely related to protein oxidation) and S-thiolated proteins (mixed disulphides of protein thiols and low molecular mass thiols), and the protein thiolation index (the molar ratio of the S-thiolated proteins to free protein thiols in plasma) have been investigated in the plasma or red blood cells of CKD and ESRD patients as possible biomarkers of oxidative stress. This type of minimally invasive analysis provides valuable information on the redox status of the less-easily accessible tissues and organs, and of the whole organism. This review provides an overview of reversible modifications in protein thiols in the setting of CKD and renal replacement therapy. The evidence suggests that protein thiols, S-thiolated proteins, and the protein thiolation index are promising biomarkers of reversible oxidative stress that could be included in the routine monitoring of CKD and ESRD patients. 相似文献
48.
Salvatore Micali Gianmarco Isgro Giampaolo Bianchi Natalizia Miceli Gioacchino Calapai Michele Navarra 《Critical reviews in food science and nutrition》2014,54(8):1063-1075
Epidemiologic studies indicate that millions of people suffer from recurrent cystitis, a pathology requiring antibiotic prophylaxis and entailing high social costs. Cranberry is a traditional folk remedy for cystitis and, which, in the form of a variety of products and formulations has over several decades undergone extensive evaluation for the management of urinary tract infections (UTI). The aim of this retrospective study is to summarize and review the most relevant and recent preclinical and clinical studies on cranberries for the treatment of UTIs. The scientific literature selected for this review was identified by searches of Medline via PubMed. A variety of recent experimental evidence has shed light on the mechanism underlying the anti-adhesive properties of proanthrocyanidins, their structure–activity relationships, and pharmacokinetics. Analysis of clinical studies and evaluation of the cranberry efficacy/safety ratio in the prevention of UTIs strongly support the use of cranberry in the prophylaxis of recurrent UTIs in young and middle-aged women. However, evidence of its clinical use among other patients remains controversial. 相似文献
49.
Salvatore Rionero 《Acta Mechanica》2013,224(2):447-458
The presence of more than one chemical dissolved in fluid mixtures is very often requested for describing natural phenomena (contaminant transport, underground water flow, acid rain effects, worming of the stratosphere). In the present paper, a triple convective-diffusive fluid mixture saturating a porous horizontal layer, heated from below and salted from above and below, is studied. In closed forms, conditions sufficient for (i) inhibiting the onset of convection and (ii) guaranteeing the global nonlinear stability of the thermal conduction solution and the absence of subcritical instabilities are obtained. 相似文献
50.
Salvatore Ventre Flavio Calvano Grégoire Pichenot Pierre Calmon Antonello Tamburrino 《NDT & E International》2011,44(4):376-386
This paper is focused on the Eddy Current Testing (ECT) method applied to important industrial applications such as the inspection of tubes in nuclear power plants and the inspection of planar surface from aeronautical industry. Specifically, we consider the prediction of the signatures produced by small defects through two fully three-dimensional numerical models developed for ECT. In particular we consider the responses to small defects described in two experimental benchmarks from nuclear power industry and one experimental benchmark from aeronautical applications. Despite of the small size of the defects that, in some cases, is of the order of few millimetres, the numerical models reproduce correctly the experimental responses provided in the benchmarks, including the challenging case of a defect (in a tube) close to the support plate. 相似文献