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211.
Rosti V Bonetti E Bergamaschi G Campanelli R Guglielmelli P Maestri M Magrini U Massa M Tinelli C Viarengo G Villani L Primignani M Vannucchi AM Frassoni F Barosi G;AGIMM Investigators 《PloS one》2010,5(12):e15277
Increased mobilization of circulating endothelial progenitor cells may represent a new biological hallmark of myeloproliferative neoplasms. We measured circulating endothelial colony forming cells (ECFCs) in 106 patients with primary myelofibrosis, fibrotic stage, 49 with prefibrotic myelofibrosis, 59 with essential thrombocythemia or polycythemia vera, and 43 normal controls. Levels of ECFC frequency for patient''s characteristics were estimated by using logistic regression in univariate and multivariate setting. The sensitivity, specificity, likelihood ratios, and positive predictive value of increased ECFC frequency were calculated for the significantly associated characteristics. Increased frequency of ECFCs resulted independently associated with history of splanchnic vein thrombosis (adjusted odds ratio = 6.61, 95% CI = 2.54–17.16), and a summary measure of non-active disease, i.e. hemoglobin of 13.8 g/dL or lower, white blood cells count of 7.8×109/L or lower, and platelet count of 400×109/L or lower (adjusted odds ratio = 4.43, 95% CI = 1.45–13.49) Thirteen patients with splanchnic vein thrombosis non associated with myeloproliferative neoplasms were recruited as controls. We excluded a causal role of splanchnic vein thrombosis in ECFCs increase, since no control had elevated ECFCs. We concluded that increased frequency of ECFCs represents the biological hallmark of a non-active myeloproliferative neoplasm with high risk of splanchnic vein thrombosis. The recognition of this disease category copes with the phenotypic mimicry of myeloproliferative neoplasms. Due to inherent performance limitations of ECFCs assay, there is an urgent need to arrive to an acceptable standardization of ECFC assessment. 相似文献
212.
Jatinder Singh Carmine Graniello Yanyan Ni Laura Payne Qila Sa James Hester Brent J. Shelton Yasuhiro Suzuki 《Microbes and infection / Institut Pasteur》2010,12(14-15):1252-1257
Toxoplasma IgG and IgA, but not IgM, antibody titers were significantly higher in immunocompetent mice with cerebral proliferation of tachyzoites during the chronic stage of infection than those treated with sulfadiazine to inhibit the parasite growth. Their IgG and IgA antibody titers correlated significantly with the amounts of tachyzoite-specific SAG1 mRNA in their brains. In contrast, neither IgG, IgA, nor IgM antibody titers increased following two different doses of challenge infection in chronically infected mice. Increased antibody titers in IgG and IgA but not IgM may be a useful indicator suggesting an occurrence of cerebral tachyzoite growth in immunocompetent individuals chronically infected with Toxoplasma gondii. 相似文献
213.
Phosphoinositide signaling molecules control cellular growth, proliferation and differentiation, intracellular vesicle trafficking, and cytoskeletal rearrangement. The inositol polyphosphate 5-phosphatase family remove the D-5 position phosphate from PtdIns(3,4,5)P3, PtdIns(4,5)P2 and PtdIns(3,5)P2 forming PtdIns(3,4)P2, PtdIns(4)P and PtdIns(3)P respectively. This enzyme family, comprising ten mammalian members, exhibit seemingly non-redundant functions including the regulation of synaptic vesicle recycling, hematopoietic cell function and insulin signaling. Here we highlight recently established insights into the functions of two well characterized 5-phosphatases OCRL and SHIP2, which have been the subject of extensive functional studies, and the characterization of recently identified members, SKIP and PIPP, in order to highlight the diverse and complex functions of this enzyme family. 相似文献
214.
Gardini G Del Boccio P Colombatto S Testore G Corpillo D Di Ilio C Urbani A Nebbia C 《Proteomics》2006,6(9):2813-2822
The use of beta-agonists, sexual steroids, and corticosteroids as growth-promoting agents (GPAs) in veal calves is forbidden in the European Union (EU) and subjected to restrictions in the US because it may be potentially noxious for both treated animals and the consumer. Although official controls performed in the EU have revealed a limited number of positive samples, the analysis of seized preparations indicate that the use of illegal GPAs is far from being abandoned. The presence of these compounds in matrixes of biological origin often goes unnoticed because of the use of very low dosages and/or of molecules of unknown chemical structure. It is therefore necessary to develop screening methods based on the biological effects of these substances that allow the simultaneous screening of many components, as proteome analysis. When hepatic cytosols and microsomes from calves treated with a combination of GPAs were analyzed by 2-DE, we found changes in the expression of two proteins, which we identified as adenosine kinase and reticulocalbin. Our aim was not to speculate about molecular mechanisms, but to show the ability of the proteomic approach to find biomarkers of illicit treatments and to use it as a basis to develop large-scale screening methods. 相似文献
215.
De Rosa S Seizova K Kamenarska Z Petrova A Iodice C Stefanov K Popov S 《Zeitschrift für Naturforschung. C, Journal of biosciences》2006,61(1-2):129-134
The sterol and fatty acid composition of three Adriatic Sea sponges (Geodia cydonium and two unidentified Tedania sp.), collected at the same time and same place, was established. Twenty-four sterols and forty fatty acids were identified. The identical ecological conditions, including the diet, allowed us to apply the results obtained for taxonomical conclusions, based on the biodiversity of the investigated sponges. On the basis of the sterol composition they can be separated into two groups: Tedania and Geodia sponges. The sterol and fatty acid composition indicates that the two investigated Tedania samples might be different species or subspecies. 相似文献
216.
Hak‐Joon Sung Prafulla Chandra Matthew D. Treiser Er Liu Carmine P. Iovine Prabhas V. Moghe Joachim Kohn 《Journal of cellular physiology》2009,218(3):549-557
The role of reactive oxygen species (ROS)‐mediated cell signal transduction pathways emanating from engineered cell substrates remains unclear. To elucidate the role, polymers derived from the amino acid L ‐tyrosine were used as synthetic matrix substrates. Variations in their chemical properties were created by co‐polymerizing hydrophobic L ‐tyrosine derivatives with uncharged hydrophilic poly(ethylene glycol) (PEG, Mw = 1,000 Da), and negatively charged desaminotyrosyl‐tyrosine (DT). These substrates were characterized for their intrinsic ability to generate ROS, as well as their ability to elicit Saos‐2 cell responses in terms of intracellular ROS production, actin remodeling, and apoptosis. PEG‐containing substrates induced both exogenous and intracellular ROS production, whereas the charged substrates reduced production of both types, indicating a coupling of exogenous ROS generation and intracellular ROS production. Furthermore, PEG‐mediated ROS induction caused nuclear translocation of glyceraldehyde‐3‐phosphate dehydrogenase and an increase in caspase‐3 activity, confirming a link with apoptosis. PEG‐rich pro‐oxidant substrates caused cytoskeletal actin remodeling through β‐actin cleavage by caspase‐3 into fractins. The fractins co‐localized to the mitochondria and reduced the mitochondrial membrane potential. The remnant cytosolic β‐actin was polymerized and condensed, events consistent with apoptotic cell shrinkage. The cytoskeletal remodeling was integral to the further augmentation of intracellular ROS production. Conversely, the anti‐oxidant DT‐containing charged substrates suppressed the entire cascade of apoptotic progression. We demonstrate that ROS activity serves an important role in “outside‐in” signaling for cells grown on substrates: the ROS activity couples exogenous stress, driven by substrate composition, to changes in intracellular signaling. This signaling causes cell apoptosis, which is mediated by actin remodeling. J. Cell. Physiol. 218: 549–557, 2009. © 2008 Wiley‐Liss, Inc. 相似文献
217.
Angelo Rita Jesus Julio Camarero Angelo Nol Marco Borghetti Michele Brunetti Nicola Pergola Carmine Serio Sergio M. Vicente‐Serrano Valerio Tramutoli Francesco Ripullone 《Global Change Biology》2020,26(2):851-863
A major component of climate change is an increase in temperature and precipitation variability. Over the last few decades, an increase in the frequency of extremely warm temperatures and drought severity has been observed across Europe. These warmer and drier conditions may reduce productivity and trigger compositional shifts in forest communities. However, we still lack a robust, biogeographical characterization of the negative impacts of climate extremes, such as droughts on forests. In this context, we investigated the impact of the 2017 summer drought on European forests. The normalized difference vegetation index (NDVI) was used as a proxy of forest productivity and was related to the standardized precipitation evapotranspiration index, which accounts for the temperature effects of the climate water balance. The spatial pattern of NDVI reduction in 2017 was largely driven by the extremely warm summer for parts of the central and eastern Mediterranean Basin (Italian and Balkan Peninsulas). The vulnerability to the 2017 summer drought was heterogeneously distributed over Europe, and topographic factors buffered some of the negative impacts. Mediterranean forests dominated by oak species were the most negatively impacted, whereas Pinus pinaster was the most resilient species. The impact of drought on the NDVI decreased at high elevations and mainly on east and north‐east facing slopes. We illustrate how an adequate characterization of the coupling between climate conditions and forest productivity (NDVI) allows the determination of the most vulnerable areas to drought. This approach could be widely used for other extreme climate events and when considering other spatially resolved proxies of forest growth and health. 相似文献
218.
Maria De Risi Giulia Torromino Michele Tufano Stphanie Moriceau Annabella Pignataro Manon Rivagorda Nicol Carrano Silvia Middei Carmine Settembre Martine Ammassari‐Teule Fabrizio Gardoni Andrea Mele Franck Oury Elvira De Leonibus 《Aging cell》2020,19(9)
Autophagy agonists have been proposed to slow down neurodegeneration. Spermidine, a polyamine that acts as an autophagy agonist, is currently under clinical trial for the treatment of age‐related memory decline. How Spermidine and other autophagy agonists regulate memory and synaptic plasticity is under investigation. We set up a novel mouse model of mild cognitive impairment (MCI), in which middle‐aged (12‐month‐old) mice exhibit impaired memory capacity, lysosomes engulfed with amyloid fibrils (β‐amyloid and α‐synuclein) and impaired task‐induced GluA1 hippocampal post‐translation modifications. Subchronic treatment with Spermidine as well as the autophagy agonist TAT‐Beclin 1 rescued memory capacity and GluA1 post‐translational modifications by favouring the autophagy/lysosomal‐mediated degradation of amyloid fibrils. These findings provide new mechanistic evidence on the therapeutic relevance of autophagy enhancers which, by improving the degradation of misfolded proteins, slow down age‐related memory decline. 相似文献
219.
Roberto Erro Carmine Vitale Marianna Amboni Marina Picillo Marcello Moccia Katia Longo Gabriella Santangelo Anna De Rosa Roberto Allocca Flavio Giordano Giuseppe Orefice Giuseppe De Michele Lucio Santoro Maria Teresa Pellecchia Paolo Barone 《PloS one》2013,8(8)
Background
The variability in the clinical phenotype of Parkinson’s disease seems to suggest the existence of several subtypes of the disease. To test this hypothesis we performed a cluster analysis using data assessing both motor and non-motor symptoms in a large cohort of newly diagnosed untreated PD patients.Methods
We collected data on demographic, motor, and the whole complex of non-motor symptoms from 100 consecutive newly diagnosed untreated outpatients. Statistical cluster analysis allowed the identification of different subgroups, which have been subsequently explored.Results
The data driven approach identified four distinct groups of patients, we have labeled: 1) Benign Pure Motor; 2) Benign mixed Motor-Non-Motor; 3) Non-Motor Dominant; and 4) Motor Dominant.Conclusion
Our results confirmed the existence of different subgroups of early PD patients. Cluster analysis revealed the presence of distinct subtypes of patients profiled according to the relevance of both motor and non-motor symptoms. Identification of such subtypes may have important implications for generating pathogenetic hypotheses and therapeutic strategies. 相似文献220.
Michele Ciro Totaro Paola Cattani Francesco Ria Barbara Tolusso Elisa Gremese Anna Laura Fedele Sara D'Onghia Simona Marchetti Gabriele Di Sante Silvia Canestri Gianfranco Ferraccioli 《Arthritis research & therapy》2013,15(3):R66