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41.
The G protein-coupled receptor GPR55 has been proposed as a new cannabinoid receptor associated with bone remodelling, nervous system excitability, vascular homeostasis as well as in several pathophysiological conditions including obesity and cancer. However, its physiological role and underlying mechanism remain unclear. In the present work, we demonstrate for the first time its presence in human macrophages and its increased expression in ox-LDL-induced foam cells. In addition, pharmacological activation of GPR55 by its selective agonist O-1602 increased CD36- and SRB-I-mediated lipid accumulation and blocked cholesterol efflux by downregulating ATP-binding cassette (ABC) transporters ABCA1 and ABCG1, as well as enhanced cytokine- and pro-metalloprotease-9 (pro-MMP-9)-induced proinflammatory responses in foam cells. Treatment with cannabidiol, a selective antagonist of GPR55, counteracted these pro-atherogenic and proinflammatory O-1602-mediated effects. Our data suggest that GPR55 could play deleterious role in ox-LDL-induced foam cells and could be a novel pharmacological target to manage atherosclerosis and other related cardiovascular diseases. 相似文献
42.
43.
Michele Carbonelli Chiara La Morgia Giacomo Savini Maria Lucia Cascavilla Enrico Borrelli Filipe Chicani Carolina do V. F. Ramos Solange R. Salomao Vincenzo Parisi Jerry Sebag Francesco Bandello Alfredo A. Sadun Valerio Carelli Piero Barboni 《PloS one》2015,10(6)
Purpose
To investigate the thickness of the retinal layers and to assess the prevalence of macular microcysts (MM) in the inner nuclear layer (INL) of patients with mitochondrial optic neuropathies (MON).Methods
All patients with molecularly confirmed MON, i.e. Leber’s Hereditary Optic Neuropathy (LHON) and Dominant Optic Atrophy (DOA), referred between 2010 and 2012 were enrolled. Eight patients with MM were compared with two control groups: MON patients without MM matched by age, peripapillary retinal nerve fiber layer (RNFL) thickness, and visual acuity, as well as age-matched controls. Retinal segmentation was performed using specific Optical coherence tomography (OCT) software (Carl Zeiss Meditec). Macular segmentation thickness values of the three groups were compared by one-way analysis of variance with Bonferroni post hoc corrections.Results
MM were identified in 5/90 (5.6%) patients with LHON and 3/58 (5.2%) with DOA. The INL was thicker in patients with MON compared to controls regardless of the presence of MM [133.1±7μm vs 122.3±9μm in MM patients (p<0.01) and 128.5±8μm vs. 122.3±9μm in no-MM patients (p<0.05)], however the outer nuclear layer (ONL) was thicker in patients with MM (101.4±1mμ) compared to patients without MM [77.5±8mμ (p<0.001)] and controls [78.4±7mμ (p<0.001)]. ONL thickness did not significantly differ between patients without MM and controls.Conclusion
The prevalence of MM in MON is low (5-6%), but associated with ONL thickening. We speculate that in MON patients with MM, vitreo-retinal traction contributes to the thickening of ONL as well as to the production of cystic spaces. 相似文献44.
Andrea Madeo Paolo Piras Federica Re Stefano Gabriele Paola Nardinocchi Luciano Teresi Concetta Torromeo Claudia Chialastri Michele Schiariti Geltrude Giura Antonietta Evangelista Tania Dominici Valerio Varano Elisabetta Zachara Paolo Emilio Puddu 《PloS one》2015,10(4)
The assessment of left ventricular shape changes during cardiac revolution may be a new step in clinical cardiology to ease early diagnosis and treatment. To quantify these changes, only point registration was adopted and neither Generalized Procrustes Analysis nor Principal Component Analysis were applied as we did previously to study a group of healthy subjects. Here, we extend to patients affected by hypertrophic cardiomyopathy the original approach and preliminarily include genotype positive/phenotype negative individuals to explore the potential that incumbent pathology might also be detected. Using 3D Speckle Tracking Echocardiography, we recorded left ventricular shape of 48 healthy subjects, 24 patients affected by hypertrophic cardiomyopathy and 3 genotype positive/phenotype negative individuals. We then applied Generalized Procrustes Analysis and Principal Component Analysis and inter-individual differences were cleaned by Parallel Transport performed on the tangent space, along the horizontal geodesic, between the per-subject consensuses and the grand mean. Endocardial and epicardial layers were evaluated separately, different from many ecocardiographic applications. Under a common Principal Component Analysis, we then evaluated left ventricle morphological changes (at both layers) explained by first Principal Component scores. Trajectories’ shape and orientation were investigated and contrasted. Logistic regression and Receiver Operating Characteristic curves were used to compare these morphometric indicators with traditional 3D Speckle Tracking Echocardiography global parameters. Geometric morphometrics indicators performed better than 3D Speckle Tracking Echocardiography global parameters in recognizing pathology both in systole and diastole. Genotype positive/phenotype negative individuals clustered with patients affected by hypertrophic cardiomyopathy during diastole, suggesting that incumbent pathology may indeed be foreseen by these methods. Left ventricle deformation in patients affected by hypertrophic cardiomyopathy compared to healthy subjects may be assessed by modern shape analysis better than by traditional 3D Speckle Tracking Echocardiography global parameters. Hypertrophic cardiomyopathy pathophysiology was unveiled in a new manner whereby also diastolic phase abnormalities are evident which is more difficult to investigate by traditional ecocardiographic techniques. 相似文献
45.
Francesco M. Carpi Silvia Vincenzetti Daniela Micozzi Alberto Vita Valerio Napolioni 《Molecular biology reports》2010,37(7):3363-3368
Cytidine deaminase (CDA) is a pyrimidine salvage pathway enzyme that catalyzes the hydrolytic deamination of cytidine and deoxycytidine to their
corresponding uracil nucleosides. CDA also catalyzes the inactivation of some chemotherapeutic nucleoside analogues such as cytosine arabinoside and gemcitabine.
CDA 79A > C (K27Q, rs2072671) and 208G > A (A70T, rs60369023) were found to be associated either with clinical outcomes as well as with pharmacokinetics and toxicity of drugs administered
to different subsets of patients. In this paper we reported two PCR-based methods for CDA 79A > C (K27Q) and 208G > A (A70T) genotyping and tested their feasibility using DNA extracted from whole blood as well as
from buccal swabs. The aim of this study was also to assess the distribution of genotypic variants in a central Italy population.
The allele frequencies were 56.3% (K*) and 43.7% (Q*) for K27Q and 100% (A*) and 0% (T*) for A70T. The genotype frequencies
were 32.8% (K*/K*), 46.9% (K*/Q*) and 20.3% (Q*/Q*) for K27Q. The genotype frequencies did not deviate from Hardy–Weinberg
equilibrium. The results were compared with those of other reported populations. They showed marked ethnic group differences. 相似文献
46.
D'Antona G Ragni M Cardile A Tedesco L Dossena M Bruttini F Caliaro F Corsetti G Bottinelli R Carruba MO Valerio A Nisoli E 《Cell metabolism》2010,12(4):362-372
Recent evidence points to a strong relationship between increased mitochondrial biogenesis and increased survival in eukaryotes. Branched-chain amino acids (BCAAs) have been shown to extend chronological life span in yeast. However, the role of these amino acids in mitochondrial biogenesis and longevity in mammals is unknown. Here, we show that a BCAA-enriched mixture (BCAAem) increased the average life span of mice. BCAAem supplementation increased mitochondrial biogenesis and sirtuin 1 expression in primary cardiac and skeletal myocytes and in cardiac and skeletal muscle, but not in adipose tissue and liver of middle-aged mice, and this was accompanied by enhanced physical endurance. Moreover, the reactive oxygen species (ROS) defense system genes were upregulated, and ROS production was reduced by BCAAem supplementation. All of the BCAAem-mediated effects were strongly attenuated in endothelial nitric oxide synthase null mutant mice. These data reveal an important antiaging role of BCAAs mediated by mitochondrial biogenesis in mammals. 相似文献
47.
Colafranceschi M Capuani G Miccheli A Campo S Valerio M Tomassini A Giuliani A Arseni B Rossi S De Santis R Carminati P Ruggiero V Conti F 《Journal of biochemical and biophysical methods》2007,70(3):355-361
A combined application of high resolution (1)H NMR spectroscopy and multivariate statistical techniques focused on establishing a consistent statistical approach to metabonomic studies was tested. The data reduction, which is preliminary to the application of multivariate analysis to NMR spectra, was carried out by means of two complementary methods: pure Pattern Recognition (PR) and Assigned Signal Analysis (ASA). The simultaneous use of both approaches allowed us to obtain additional information in the analysis of metabonomic data, compared to the use of PR alone. This additional information consists in the possibility of a biochemical interpretation of the effects induced by treatment with xenobiotics, such as drugs or drug vehicles, on the metabolic networks of the systems under investigation. This approach allowed us to ascertain that a single-dose treatment with ST1959 vehicled by Sesame oil affects the production of hepatic glucose associated to an increment of the amino acid ketogenic process. 相似文献
48.
Euscorpius tergestinus (C.L. Koch, 1837), Euscorpius concinnus (C.L. Koch, 1837) and Euscorpius sicanus (C.L. Koch, 1837), three presumed closely related species belonging to the "carpathicus group", occur in the Italian peninsula with a largely parapatric distribution and some zones of range overlap. These areas of sympatry represent interesting opportunities to investigate species boundaries in natural populations. Here we report on a study exploring genetic variation in sympatric populations of the three species from central Tuscany. Additional collecting sites, from different localities across Italy, were also included in the analysis in order to explore the phylogeographic structure of the group. Species boundaries and evolutionary relationships were examined by sequence comparison of mitochondrial 16S rRNA and nuclear ITS-1 rRNA gene fragments. DNA sequence data show no evidence of genetic introgression between different evolutionary lineages from the area of range overlap, suggesting the absence of either past or ongoing inter-specific gene flow. It is therefore probable that reproductive barriers exist, preventing gene pools from amalgamating. Furthermore, our results support the recent morphological distinction of E. tergestinus, as traditionally classified, into two different species: E. tergestinus and E. concinnus. Both mitochondrial and nuclear sequence data clearly indicate that the two taxa represent well-supported and deeply divergent lineages. Euscorpius sicanus seems to represent a monophyletic taxon, but the high genetic variability observed within this taxon calls for future investigation. The present distribution patterns across the Italian peninsula were mainly interpreted as the consequence of climatic oscillations. 相似文献
49.
Giuseppe Maria Carpaneto Adriano Mazziotta Laura Valerio 《Diversity & distributions》2007,13(6):903-919
The decline of roller dung beetles (Coleoptera, Scarabaeidae) in Italy, at national and regional level, was described using a database of both literature and unpublished data, since the late of 19th century. The probability of finding roller species was assessed for each decade of the 20th century in order to detect changes in their distribution and status. An analysis of decline was performed using a complementary approach of different extinction indexes, according to IUCN criteria. During the 20th century, both the absolute number of records and the UTM cells where roller beetles were found increased clearly as a consequence of the escalation of entomological surveys. Nevertheless, comparing R species (rollers) with all the scarab dung beetles from the first to the last quarter of the 20th century, the relative frequency of roller records decreased by 31%, while the relative number of occupied UTM cells dropped by 23%. Six roller species showed a significant decline in Italy from the first to the second part of the 20th century, and nine in the last 30years. Other two species disappeared from the majority of the northern regions. Finally, the values of all the extinction indexes were strongly correlated and detected a high risk of extinction in Italy for six species. A gradual change in land use during the last three decades, consisting of a reduced extension of grasslands in favour of either intensive agriculture or reforestation after abandonment of livestock raising, was likely the main factor inducing decline and local extinction of roller species. 相似文献
50.
Sbragaglia Valerio Espasandín Lucía Coco Salvatore Felici Alberto Correia Ricardo A. Coll Marta Arlinghaus Robert 《Reviews in Fish Biology and Fisheries》2022,32(2):687-700
Reviews in Fish Biology and Fisheries - Fisheries are among the human activities that are most strongly affected by ongoing climate-related changes in the presence and abundance of fish species... 相似文献