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81.
Stefano Lancellotti Vincenzo De Filippis Nicola Pozzi Flora Peyvandi Roberta Palla Bianca Rocca Sergio Rutella Dario Pitocco Pier Mannuccio Mannucci Raimondo De Cristofaro 《Free radical biology & medicine》2010,48(3):446-456
An enhanced formation of reactive oxygen species and peroxynitrite occurs in several clinical settings including diabetes, coronary artery disease, stroke, sepsis, and chronic inflammatory diseases. Peroxynitrite oxidizes methionine and tyrosine residues to methionine sulfoxide (MetSO) and 3-nitrotyrosine (NT), respectively. Notably, ADAMTS-13 cleaves von Willebrand factor (VWF) exclusively at the Tyr1605–Met1606 peptide bond in the A2 domain. We hypothesized that peroxynitrite could oxidize either or both of these amino acid residues, thus potentially affecting ADAMTS-13-mediated cleavage. We tested our hypothesis using synthetic peptide substrates based on: (1) VWF Asp1596–Ala1669 sequence (VWF74) and (2) VWF Asp1596–Ala1669 sequence containing nitrotyrosine (VWF74-NT) or methionine sulfoxide (VWF74-MetSO) at position 1605 or 1606, respectively. The peptides were treated with recombinant ADAMTS-13 and the cleavage products analyzed by RP-HPLC. VWF74 oxidized by peroxynitrite underwent a severe impairment of its hydrolysis. Likewise, VWF74-MetSO was minimally hydrolyzed, whereas VWF74-NT was hydrolyzed slightly more efficiently than VWF74. Oxidation by peroxynitrite of purified VWF multimers inhibited ADAMTS-13 hydrolysis, but did not alter their electrophoretic pattern nor their ability to induce platelet agglutination by ristocetin. Moreover, VWF purified from type 2 diabetic patients showed oxidative damage, as revealed by enhanced carbonyl, NT, and MetSO content and was partially resistant to ADAMTS-13 hydrolysis. In conclusion, peroxynitrite may contribute to prothrombotic effects, hindering the proteolytic processing by ADAMTS-13 of high-molecular-weight VWF multimers, which have the highest ability to bind and activate platelets in the microcirculation. 相似文献
82.
83.
Monogeneans belonging to the genus Ligophorus Euzet & Suriano, 1977 are parasitic on the gills of several fish species of the family Mugilidae (mullets). At present, 12 species belonging to this genus have been described in the Mediterranean Sea and each host species is infected by a number of Ligophorus species that are not found on other mullets. A multivariate study using principal component and canonical variate analyses was carried out, with the aim of investigating the extent of morphometric variability within and between the 12 Mediterranean species of Ligophorus. Significant intraspecific morphometric variation was detected between two allopatric populations of L. angustus Euzet & Suriano, 1977 parasitic on Chelon labrosus from Sardinia; however, the existence of a new species of Ligophorus needs further evidence. Analysis of interspecific variation confirms the validity of the morphological keys used at present for the identification of Ligophorus at the species level and provides a picture of the relationships between species, indicating that the two species parasitising Mugil cephalus, L. chabaudi Euzet & Suriano, 1977 and L. mugilinus (Hargis, 1955) are the most differentiated. The hypothesis that strict host-parasite ecological relationships may be the result of co-speciation processes is briefly discussed. 相似文献
84.
Paolo Martini Gabriele Sales Mattia Brugiolo Alessandro Gandaglia Filippo Naso Cristiano De Pittà Michele Spina Gino Gerosa Francesco Chemello Chiara Romualdi Stefano Cagnin Gerolamo Lanfranchi 《PloS one》2014,9(4)
Background
Despite the economic and medical importance of the pig, knowledge about its genome organization, gene expression regulation, and molecular mechanisms involved in physiological processes is far from that achieved for mouse and rat, the two most used model organisms in biomedical research. MicroRNAs (miRNAs) are a wide class of molecules that exert a recognized role in gene expression modulation, but only 280 miRNAs in pig have been characterized to date.Results
We applied a novel computational approach to predict species-specific and conserved miRNAs in the pig genome, which were then subjected to experimental validation. We experimentally identified candidate miRNAs sequences grouped in high-confidence (424) and medium-confidence (353) miRNAs according to RNA-seq results. A group of miRNAs was also validated by PCR experiments. We established the subtle variability in expression of isomiRs and miRNA-miRNA star couples supporting a biological function for these molecules. Finally, miRNA and mRNA expression profiles produced from the same sample of 20 different tissue of the animal were combined, using a correlation threshold to filter miRNA-target predictions, to identify tissue-specific regulatory networks.Conclusions
Our data represent a significant progress in the current understanding of miRNAome in pig. The identification of miRNAs, their target mRNAs, and the construction of regulatory circuits will provide new insights into the complex biological networks in several tissues of this important animal model. 相似文献85.
Pasquale V Romano VJ Rupnik M Dumontet S Cižnár I Aliberti F Mauri F Saggiomo V Krovacek K 《Folia microbiologica》2011,56(5):431-437
This pilot study was carried out to evaluate the occurrence of Clostridium difficile in marine environments and in edible shellfish. Samples of seawater, sediment, and zooplankton were collected at five sampling
stations in the Gulf of Naples. Six samples of edible shellfish, furthermore, were obtained: two from mussel farms and four
from wholesalers. The isolation and the characterization of C. difficile strains were carried out using selective media and molecular techniques, respectively. C. difficile was isolated from nine of the 21 samples investigated. Shellfish and zooplankton showed the highest prevalence of positive
samples. No C. difficile was detected in marine sediment. Majority of the C. difficile isolates were toxin A/B positive. Six known different PCR ribotypes (003, 005, 009, 010, 056, and 066) were identified, whereas
one strain may represent a new PCR ribotype. C. difficile may be present in the marine environment in Southern Italy, including shellfish and zooplankton. This study is reporting
the isolation of C. difficile from zooplankton, clams, and mussels and pointing out a new possible route to exposure to C. difficile of healthy individuals in the community. 相似文献
86.
Pavan S Schiavulli A Appiano M Marcotrigiano AR Cillo F Visser RG Bai Y Lotti C Ricciardi L 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2011,123(8):1425-1431
The powdery mildew disease affects several crop species and is also one of the major threats for pea (Pisum sativum L.) cultivation all over the world. The recessive gene er1, first described over 60 years ago, is well known in pea breeding, as it still maintains its efficiency as a powdery mildew
resistance source. Genetic and phytopathological features of er1 resistance are similar to those of barley, Arabidopsis, and tomato mlo powdery mildew resistance, which is caused by the loss of function of specific members of the MLO gene family. Here, we describe the obtainment of a novel er1 resistant line by experimental mutagenesis with the alkylating agent diethyl sulfate. This line was found to carry a single
nucleotide polymorphism in the PsMLO1 gene sequence, predicted to result in premature termination of translation and a non-functional protein. A cleaved amplified
polymorphic sequence (CAPS) marker was developed on the mutation site and shown to be fully co-segregating with resistance
in F2 individuals. Sequencing of PsMLO1 from three powdery mildew resistant cultivars also revealed the presence of loss-of-function mutations. Taken together, results
reported in this study strongly indicate the identity between er1 and mlo resistances and are expected to be of great breeding importance for the development of resistant cultivars via marker-assisted
selection. 相似文献
87.
Bianchi FT Camera P Ala U Imperiale D Migheli A Boda E Tempia F Berto G Bosio Y Oddo S LaFerla FM Taraglio S Dotti CG Di Cunto F 《PloS one》2011,6(7):e22370
Alzheimer disease (AD) is a neurodegenerative disorder characterized by progressive decline of cognitive function that represents one of the most dramatic medical challenges for the aging population. Aβ peptides, generated by processing of the Amyloid Precursor Protein (APP), are thought to play a central role in the pathogenesis of AD. However, the network of physical and functional interactions that may affect their production and deposition is still poorly understood. The use of a bioinformatic approach based on human/mouse conserved coexpression allowed us to identify a group of genes that display an expression profile strongly correlated with APP. Among the most prominent candidates, we investigated whether the collagen chaperone HSP47 could be functionally correlated with APP. We found that HSP47 accumulates in amyloid deposits of two different mouse models and of some AD patients, is capable to physically interact with APP and can be relocalized by APP overexpression. Notably, we found that it is possible to reduce the levels of secreted Aβ peptides by reducing the expression of HSP47 or by interfering with its activity via chemical inhibitors. Our data unveil HSP47 as a new functional interactor of APP and imply it as a potential target for preventing the formation and/or growth amyloid plaques. 相似文献
88.
Mahdavinia M Bishehsari F Verginelli F Cumashi A Lattanzio R Sotoudeh M Ansari R Semeraro D Hormazdi M Fakheri H Rakhshani N De Lellis L Curia MC Cama A Piantelli M Malekzadeh R Iacobelli S Mariani-Costantini R 《Journal of cellular physiology》2008,216(2):543-550
CRC-associated P53 mutations have not been studied extensively in non-Western countries at relatively low CRC risk. We examined, for the first time, 196 paraffin-embedded CRC cases from Northern Iran for mutations in P53 exons 5-8 using PCR-direct sequencing. P53 status and mutation site/type were correlated with nuclear protein accumulation, clinicopathologic variables and data on K-ras mutations and high-level microsatellite instability (MSI-H). We detected 96 P53 mutations in 87 (44.4%) cases and protein accumulation in 84 cases (42.8%). P53 mutations correlated directly with stage and inversely with MSI-H. Distal CRCs were more frequently mutated at major CpG hotspot codons [248 (8/66, 12.1%), 175 (7/66, 10.6%), and 245 (7/66, 10.6%)], while in proximal tumors codon 213, emerged as most frequently mutated (5/28, 17.9% vs. 3/66, 4.5%, P = 0.048). Transitions at CpGs, the most common mutation type, were more frequent in non-mucinous (25% vs. 10.4% in mucinous, P = 0.032), and distal CRC (27% vs. 12.5% in proximal, P = 0.02), and correlated with K-ras transversions. Transitions at non-CpGs, second most common P53 mutation, were more frequent in proximal tumors (15.6% vs. 4.7% in distal, P = 0.01), and correlated with K-ras transitions and MSI-H. Overall frequency and types of mutations and correlations with P53 accumulation, stage and MSI-H were as reported for non-Iranian patients. However P53 mutation site/type and correlations between P53 and K-ras mutation types differed between proximal and distal CRC. The codon 213 P53 mutation that recurred in proximal CRC was previously reported as frequent in esophageal cancer from Northern Iran. 相似文献
89.
Stefano M. Candura Anna F. Castoldi Luigi Manzo Lucio G. Costa 《Neurochemical research》1992,17(11):1133-1141
Guanine nucleotide-, neurotransmitter-, and fluoride-stimulated accumulation of [3H]inositol phosphates ([3H]InsPs) was measured in [3H]inositol-labeled synaptoneurosomes from cerebral cortex of immature (7-day-old) and adult rats, in order to clarify the role of GTP-binding proteins (G-proteins) in modulating phosphoinositide (PtdIns) metabolism during brain development. GTP(S) [Guanosine 5-O-(3-thio)triphosphate] time- and concentration-dependently stimulated PtdIns hydrolysis. Its effect was potentiated by full (carbachol, metacholine) and partial (oxotremorine) cholinergic agonists through activation of muscarinic receptors. The presence of deoxycholate was required to demonstrate agonist protentiation of the guanine nucleotide effect. The response to GTP(S) was higher in adult than in immature rats, while the effect of cholinergic agonists was similar at the two ages examined. At both ages, histamine potentiated the effect of GTP(S), while norepinephrine was ineffective. At both ages, guanosine 5-O-(2-thio)diphosphate [GDP(S)] and pertussis toxin significantly decreased GTP(S)-induced [3H]InsPs formation. The phorbol ester phorbol 12-myristate 13-acetate (PMA), on the other hand, did not inhibit the guanine nucleotide response in synaptoneurosomes from immature rats. NaF mimicked the action of GTP(S) in stimulating PtdIns hydrolysis. Its effect was not affected by carbachol and was highly synergistic with that of AlCl3, according to the concept that fluoroaluminate (AlF4
–) is the active stimulatory species. No quantitative differences were found in the response to these salts between immature and adult animals. These results provide evidence that, in both the immature and adult rat brain, neuroreceptor activation is coupled to PtdIns hydrolysis through modulatory G-proteins. 相似文献
90.
Effects on interfacial properties and cell adhesion of surface modification by pectic hairy regions 总被引:1,自引:0,他引:1
Morra M Cassinelli C Cascardo G Nagel MD Della Volpe C Siboni S Maniglio D Brugnara M Ceccone G Schols HA Ulvskov P 《Biomacromolecules》2004,5(6):2094-2104
Polystyrene Petri dishes, aminated by a plasma deposition process, were surface modified by the covalent linking of two different enzymatically modified hairy regions (HRs) from pectin containing, for example, rhamnogalacturonan-I and xylogalacturonan structural elements. The two polysaccharide preparations share the same structural elements of apple pectin, but the relative amounts and lengths of the neutral side chains present differ. Surface analysis by X-ray photoelectron spectroscopy, contact angle measurement, and atomic force microscope (AFM) force-separation curves was used to characterize the effects on surface chemistry and interfacial forces of the surface modification process. Cell adhesion experiments using continuous L-929 fibroblasts and primary aortic smooth muscle cells were performed to evaluate the effect of the polysaccharide nature on cell adhesion. Results show that immobilization of the HR affects the interfacial field of forces and the cell behavior: "equilibrium" contact angles, obtained by a recently introduced vibrational approach, decrease after HR immobilization reaching a value close to 20 degrees . AFM force-separation curves show a more extended (or softer) interface in the case of the HR bearing longer side chains. Accordingly, depending on the HR preparation, cells shifted from spread morphology and adhesion behavior quantitatively comparable to that observed on conventional tissue culture polystyrene to rounded morphology and significantly lower adhesion. These data show that engineering of plant pectins can be a valuable tool to prepare novel and finely tuned polysaccharides having different chemico-physical and biological properties, to be used in the surface modification of medical devices and materials. 相似文献