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81.
Defibrotide, (D) an antithrombotic agent, when administered i.v. to cholesterol-fed rabbits decreased cholesterol in the aorta without changing total plasma cholesterol, triglyceride or phospholipid, nor the cholesterol, triglyceride, phospholipid and protein of plasma lipoproteins. Platelet aggregation was decreased in rabbits treated with D. There were fewer vascular lesions in the hearts and kidneys of animals treated with D than in animals fed cholesterol and treated with placebo. These data suggest that the antithrombotic activity of D and its ability to reduce platelet sensitivity could help to reduce the amount of cholesterol in the cardiovascular system in atherosclerosis-prone situations. 相似文献
82.
R Porta C Esposito V Gentile L Mariniello G Peluso S Metafora 《International journal of peptide and protein research》1990,35(2):117-122
One of the major proteins secreted from the rat seminal vesicle epithelium, namely SV-IV, was shown to act in vitro as acyl donor and acceptor substrate for transglutaminase from both guinea pig liver and rat anterior prostate secretory fluid. Electrophoretic and chromatographic experiments indicated that the enzyme catalyzed the formation of multiple modified forms of SV-IV. In the absence of small Mr amines, transglutaminase was able to produce at least six different molecular forms of the protein, half of which possessed an Mr higher than that of native SV-IV. These findings suggested that a variable number of intermolecular, and perhaps intramolecular, crosslinks were formed between one or both glutamine residues and one or more lysine residues occurring in the SV-IV polypeptide chain. In addition, at least three modified forms of the protein were produced by transglutaminase in the presence of high concentrations of spermidine, thus indicating the formation of different (gamma-glutamyl)polyamine derivatives of SV-IV. Rabbit uteroglobin and rat anterior prostate secretory protein(s) were also shown to be able to covalently bind spermidine in the presence of the enzyme. The possible biological significance of transglutaminase-mediated modifications of SV-IV, as well as of other proteins occurring in the mammal seminal fluid, are discussed. 相似文献
83.
Raffaele Porta Concetta Valeria L. Giosafatto Prospero di Pierro Angela Sorrentino Loredana Mariniello 《Amino acids》2013,44(1):285-292
Hen egg can cause food hypersensitivity in infants and young children, and ovomucoid is the most allergenic factor among proteins contained in egg white. Since proteinase treatment, a well-recognized strategy in reducing food allergenicity, is ineffective when applied to ovomucoid because of its ability to act as trypsin inhibitor, we investigated the possibility of reducing the ovomucoid antiprotease activity and antigenic properties by covalently modifying its structure. The present paper reports data showing the ability of the Gln115 residue of ovomucoid to act as an acyl donor substrate for the enzyme transglutaminase and, as a consequence, to give rise to a covalent monodansylcadaverine conjugate of the protein in the presence of both enzyme and the diamine dansylated derivative. Moreover, we demonstrated that the obtained structural modification of ovomucoid significantly reduced the capability of the protein to inhibit trypsin activity, also having impact on its anti-ovomucoid serum-binding properties. 相似文献
84.
R Porta D Moltrasio R Pescador E Lanzarotti M Mantovani G Prino 《Analytical biochemistry》1992,204(1):143-146
We describe an HPLC method for the determination of whole polydeoxyribonucleotides in animal plasma. This method was compared to a colorimetric method, which evaluates the sugar moiety of polydeoxyribonucleotides, and to an agarose gel electrophoresis method, which evaluates the whole polydeoxyribonucleotides as does the HPLC method, and was found to give results very close to those obtained with these two other methods. A pharmacokinetic study of the antithrombotic, profibrinolytic, polydeoxyribonucleotidic drug defibrotide was carried out by evaluating the plasma drug levels by these three methods. The pharmacokinetic parameters calculated from the data are very similar. 相似文献
85.
Emre Brookes Borries Demeler Camillo Rosano Mattia Rocco 《European biophysics journal : EBJ》2010,39(3):423-435
The interpretation of solution hydrodynamic data in terms of macromolecular structural parameters is not a straightforward
task. Over the years, several approaches have been developed to cope with this problem, the most widely used being bead modeling
in various flavors. We report here the implementation of the SOMO (SOlution MOdeller; Rai et al. in Structure 13:723–734,
2005) bead modeling suite within one of the most widely used analytical ultracentrifugation data analysis software packages, UltraScan
(Demeler in Modern analytical ultracentrifugation: techniques and methods, Royal Society of Chemistry, UK, 2005). The US-SOMO version is now under complete graphical interface control, and has been freed from several constraints present
in the original implementation. In the direct beads-per-atoms method, virtually any kind of residue as defined in the Protein
Data Bank (e.g., proteins, nucleic acids, carbohydrates, prosthetic groups, detergents, etc.) can be now represented with
beads whose number, size and position are all defined in user-editable tables. For large structures, a cubic grid method based
on the original AtoB program (Byron in Biophys J 72:408–415, 1997) can be applied either directly on the atomic structure, or on a previously generated bead model. The hydrodynamic parameters
are then computed in the rigid-body approximation. An extensive set of tests was conducted to further validate the method,
and the results are presented here. Owing to its accuracy, speed, and versatility, US-SOMO should allow to fully take advantage
of the potential of solution hydrodynamics as a complement to higher resolution techniques in biomacromolecular modeling. 相似文献
86.
Loredana Mariniello Maria Grazia Sommella Angela Sorrentino Marcello Forlani Raffaele Porta 《Biotechnology letters》2002,24(10):749-755
Nineteen cultivars of apricot (Prunus armeniaca) were distinguished using random amplified polymorphic DNA (RAPD) markers. One decamer out of 44 used was useful to differentiate cultivars of the Campania Region from those of Northern Italy, North America and Greece. A sequence characterized amplified region (SCAR) marker was obtained. The results provide a protocol to fingerprint DNA of apricots as an efficient way to quality control and fraud prevention. 相似文献
87.
USPIO‐labeling in M1 and M2‐polarized macrophages: An in vitro study using a clinical magnetic resonance scanner
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88.
Roney Fontes Guimarães Luciana Rodrigues Camillo Aurizangela Oliveira Sousa Luana Pereira Gonçalves Jamilly Costa Cardoso Macedo Giovano Sousa Siqueira Antônia Marlene Magalhães Barbosa Fátima Cerqueira Alvim Marcio Gilberto Cardoso Costa Carlos Priminho Pirovani 《Tree Genetics & Genomes》2018,14(6):90
Here, we report for the first time the genome-wide identification and expression analysis of the molecular chaperone BiP genes in Citrus. Six genes encoding the conserved protein domain family GPR78/BiP/KAR2 were identified in the genome of Citrus sinensis and C. clementina. Two of them, named here as CsBiP1 and CsBiP2, were classified as true BiPs based on their deduced amino acid sequences. Alignment of the deduced amino acid sequences of CsBiP1 and CsBiP2 with BiP homologs from soybean and Arabidopsis showed that they contain all the conserved functional motifs of BiPs. Analysis of the promoter region of CsBiPs revealed the existence of cis-acting regulatory sequences involved in abiotic, heat-shock, and endoplasmic reticulum (ER) stress responses. Publicly available RNA-seq data indicated that CsBiP1 is abundantly expressed in leaf, flower, fruit, and callus, whereas CsBiP2 expression is rarely detected in any tissues under normal conditions. Comparative quantitative real-time PCR (qPCR) analysis of expression of these genes between C. sinensis grafted on the drought-tolerant “Rangpur” lime (C. limonia) and -sensitive “Flying Dragon” trifoliate orange (Poncirus trifoliata) rootstocks showed that CsBiP1 was upregulated by drought stress on the former but downregulated on the latter, whereas the CsBiP2 mRNA levels were downregulated on drought-stressed “Flying Dragon,” but remained constant on “Rangpur.” CsBiP2 upregulation was only observed in C. sinensis seedlings subjected to osmotic and cold treatments. Taken together, these results indicate the existence of two highly conserved BiP genes in Citrus that are differentially regulated in the different tissues and in response to abiotic stresses. 相似文献
89.
90.
Blood flow interruption is associated with oxygen depletion and loss of factors for function and survival in downstream tissues or cells. Hypoxia and absence of gonadotropins trigger apoptosis and atresia in the ovary. We studied the antioxidant response of follicular cells to plasma deprivation in ovaries dissected from water buffalo. Aliquots of follicular fluid were aspirated from each antral follicle, before and during incubation of the ovaries at 39 degrees C. Urate, ascorbate, retinol and alpha-tocopherol in the fluid were, titrated by High Performance Liquid Chromatography (HPLC) with spectrophotometric or spectrofluorimetric detection. The total antioxidant capacity of follicular fluid was determined as absorbance decrease, following addition of a source of radical chromophores. The more the incubation progressed, the higher levels of urate, ascorbate and total antioxidant capacity were found. Conversely, changes in concentration of the liposoluble antioxidants were not observed. Ascorbate synthesizing activity in the follicle was demonstrated by detecting the enzyme L-gulono-gamma-lactone oxidase in microsomes prepared from granulosa cells. These cells were also analyzed for the expression of the enzyme CPP32. The enzyme level, measured as DEVD-p-nitroanilide cleaving activity, was found related with the immunoreactivity to anti-CPP32 antibodies. Negative correlation between the enzyme activity (which is known to be induced by peroxynitrite) and the follicular level of urate (which scavenges peroxynitrite) was also observed. The amount of nitrotyrosine, a product of peroxynitrite attack on proteins, was measured in follicular fluids by Enzyme Linked ImmunoSorbent Assay (ELISA). This amount was found positively correlated with the CPP32 activity, and negatively correlated with the urate level in follicular fluid. Alterations in concentrations of ascorbate or urate may be associated with oxidative stress during follicular atresia. 相似文献