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51.
AbstractBackground: With the rapid rise in opioid overdose-related deaths, state policy makers have expanded policies to increase the use of naloxone by emergency medical services (EMS). However, little is known about changes in EMS naloxone administration in the context of continued worsening of the opioid crisis and efforts to increase use of naloxone. This study examines trends in patient demographics and EMS response characteristics over time and by county urbanicity. Methods: We used data from the 2013–2016 National EMS Information System to examine trends in patient demographics and EMS response characteristics for 911-initiated incidents that resulted in EMS naloxone administration. We also assessed temporal, regional, and urban–rural variation in per capita rates of EMS naloxone administrations compared with per capita rates of opioid-related overdose deaths. Results: From 2013 to 2016, naloxone administrations increasingly involved young adults and occurred in public settings. Particularly in urban counties, there were modest but significant increases in the percentage of individuals who refused subsequent treatment, were treated and released, and received multiple administrations of naloxone before and after arrival of EMS personnel. Over the 4-year period, EMS naloxone administrations per capita increased at a faster rate than opioid-related overdose deaths across urban, suburban, and rural counties. Although national rates of naloxone administration were consistently higher in suburban counties, these trends varied across U.S. Census Regions, with the highest rates of suburban administration occurring in the South. Conclusions: Naloxone administration rates increased more quickly than opioid deaths across all levels of county urbanicity, but increases in the percentage of individuals requiring multiple doses and refusing subsequent care require further attention. 相似文献
52.
Chantal Loirat Fadi Fakhouri Gema Ariceta Nesrin Besbas Martin Bitzan Anna Bjerre Rosanna Coppo Francesco Emma Sally Johnson Diana Karpman Daniel Landau Craig B Langman Anne-Laure Lapeyraque Christoph Licht Carla Nester Carmine Pecoraro Magdalena Riedl Nicole C. A. J. van de Kar Johan Van de Walle Marina Vivarelli Véronique Frémeaux-Bacchi for HUS International 《Pediatric nephrology (Berlin, Germany)》2016,31(1):15-39
53.
54.
Hearnden Vanessa Powers Hilary J. Elmogassabi Abeir Lowe Rosanna Murdoch Craig 《European journal of nutrition》2018,57(4):1321-1332
European Journal of Nutrition - DNA methylation plays a fundamental role in the epigenetic control of carcinogenesis and is, in part, influenced by the availability of methyl donors obtained from... 相似文献
55.
Carolina Cefaliello Maria Eyman Dominique Melck Rosanna De Stefano Eugenia Ferrara Marianna Crispino Antonio Giuditta 《Journal of neuroscience research》2014,92(11):1573-1580
Synaptosomal protein synthesis from rat brain is selectively increased by learning and is massively enhanced during the recovery period from brain ischemia. To lay the groundwork for identification of the involved synaptic elements, we examined the effects induced by varying the concentrations of extracellular cations and endogenous calcium. Most of the recorded rate response curves exhibited biphasic profiles that suggested the presence of more than one translation system. Because comparable profiles were obtained by fully inhibiting mitochondrial translation, the data indicated the involvement of cytoplasmic translation systems present in different synaptosomal classes. Their properties may be individually investigated by exploiting the partially inhibited conditions we have described. The identification of the synaptic elements from which they originated and their newly synthesized proteins will significantly expand our understanding of the synaptic contribution to brain plastic events. © 2014 Wiley Periodicals, Inc. 相似文献
56.
Identification of the hemangioblast in postnatal life 总被引:28,自引:11,他引:28
Pelosi E Valtieri M Coppola S Botta R Gabbianelli M Lulli V Marziali G Masella B Müller R Sgadari C Testa U Bonanno G Peschle C 《Blood》2002,100(9):3203-3208
57.
Asselta R Spena S Duga S Peyvandi F Malcovati M Mannucci PM Tenchini ML 《Haematologica》2002,87(8):855-859
BACKGROUND AND OBJECTIVES: Congenital afibrinogenemia is a rare coagulation disorder whose molecular basis is still poorly characterized. Most mutations have been identified in the fibrinogen Aalpha- and gamma-chain genes, whereas only two missense mutations have been reported in the Bbeta-chain gene. The aim of this work was to widen knowledge about the mutational spectrum of this disease by analyzing the molecular bases of congenital afibrinogenemia in three unrelated Iranian patients. DESIGN AND METHODS: All patients showed unmeasurable levels of clottable fibrinogen in plasma. Mutational screening was performed by sequencing the whole coding region, including exon-intron boundaries and part of the promoter region of the three fibrinogen genes. RESULTS: Sequencing in one patient revealed the presence of a novel nonsense mutation (3282C-->T) in exon 2 of the fibrinogen Bbeta-chain gene, causing a severe truncation of the corresponding polypeptide (R17X). In the remaining probands, two already known small deletions (4209delA and 4220delT), both located in exon 5 of the fibrinogen Aalpha-chain gene, were identified, and their effect at the protein level explored by computer-assisted analysis. INTERPRETATION AND CONCLUSIONS: The identification of the first truncating mutation in the fibrinogen Bbeta-chain gene confirms the involvement of all three fibrinogen genes in the pathogenesis of congenital afibrinogenemia and widens the mutational spectrum of the disease. This knowledge is clinically essential in order to carry out prenatal diagnosis in families at risk. 相似文献
58.
Identification of a transient excision intermediate at the crossroads between DNA polymerase extension and proofreading pathways 总被引:4,自引:0,他引:4 下载免费PDF全文
Rosanna P. Baker Linda J. Reha-Krantz 《Proceedings of the National Academy of Sciences of the United States of America》1998,95(7):3507-3512
DNA polymerases achieve accurate DNA replication through a delicate balance between primer elongation and proofreading. While insufficient proofreading results in DNA replication errors, indiscriminate removal of correct along with incorrect nucleotides is wasteful and may prevent completion of DNA synthesis. The transition between polymerization and proofreading modes is proposed to be governed by a kinetic barrier that prevents proofreading unless the rate of primer elongation is significantly reduced by the presence of an incorrect base pair at the primer–terminus. We have used mutational analysis, coupled with a sensitive, fluorescence-based assay to characterize intermediate steps in the proofreading pathway. A highly fluorescent complex forms between the bacteriophage T4 DNA polymerase and DNA primer–templates labeled at the 3′ terminus with the base analog 2-aminopurine. Formation of the fluorescent complex appears to be a rate-determining step in the proofreading pathway and is impaired for several mutator T4 DNA polymerases with amino acid substitutions in the exonuclease domain. Although these mutant DNA polymerases are proficient in hydrolysis, their reduced ability to form the fluorescent complex imposes a higher kinetic barrier. As a consequence, the mutant DNA polymerases proofread less frequently, resulting in more DNA replication errors. 相似文献
59.
Paolo Bechi MD Dr. Paolo Romagnoli MD Pertti Panula MD Rosanna Dei BS Stefano Bacci BS Andrea Amorosi MD Emanuela Masini MD 《Digestive diseases and sciences》1995,40(10):2207-2213
Gastric mucosal histamine content, enterochromaffin-like cell density, and mast cell density were studied in 13 subjects under omeprazole therapy, 13 partially gastrectomized subjects with a Billroth II reconstruction, 10 partially gastrectomized subjects with a Roux-en-Y reconstruction, and 9 control subjects. Histamine content was significantly greater both in the subjects with higher gastrinemic levels (omeprazole-treated subjects) and those with more abundant enterogastric reflux (Billroth II subjects) than in controls. Enterochromaffin-like cell density was significantly greater in the omeprazole subjects than in each of the other groups. Mast cell density was significantly greater in Billroth II subjects than in controls. Serum gastrin levels, mucosal histamine content, and enterochromaffin-like cell density were positively correlated. Gastrin was not correlated to mast cell densilty. These results support the existence of different control pathways for enterochromaffin-like and mast cells. Moreover, they suggest that enterochromaffin-like cells and mast cells are involved in the regulation of gastric secretion and in gastric mucosal injury-repair mechanisms, respectively, due to histamine release. 相似文献
60.
Villa P Perri C Suriano R Cucinelli F Panunzi S Ranieri M Mele C Lanzone A 《The Journal of clinical endocrinology and metabolism》2005,90(8):4622-4629
CONTEXT: Hyperhomocysteinemia as well as alterations of glycemic and lipidic metabolism are recognized as risk factors for cardiovascular diseases. OBJECTIVE: The aim of this study was to examine the effect of L-folic acid supplementation on homocysteine (Hcy) and related thiols, such as cysteine (Cys) and Cys-glycine (Cys-Glyc) pathways and their relationship to glucose, insulin, and lipidic metabolism in normoinsulinemic postmenopausal women. DESIGN: This study was a randomized placebo, not double-blind, trial. SETTING: The study was performed in an academic research center. PATIENTS OR OTHER PARTICIPANTS: Twenty healthy postmenopausal women were selected. No patient was taking drugs known to affect lipid or glucose metabolism. INTERVENTION(S): Patients underwent two hospitalizations before and after 8 wk of L-acid folic (7.5 mg/d) or placebo administration. The glycemic metabolism was studied by an oral glucose tolerance test and a hyperinsulinemic euglycemic clamp. Hcy metabolism was studied by a standardized oral methionine-loading test. MAIN OUTCOME MEASURE(S): Hcy, Cys, and Cys-Glyc, basally and after a methionine loading test, were measured. Basal insulin, glucose, and peptide C levels as well as area under the curve for insulin, area under the curve for peptide, hepatic insulin extraction, and metabolic index were assayed. The total cholesterol, high-density lipoprotein (HDL) cholesterol, and low-density lipoprotein (LDL) cholesterol levels and the cholesterol/HDL and LDL/HDL ratios were also measured. RESULTS: The total basal Hcy concentration and the plasma postmethionine loading Hcy values were significantly decreased (P < 0.01) in L-folic acid-treated patients, whereas postmethionine loading Cys-Glyc levels were markedly increased (P < 0.02). Furthermore, L-folic acid intake induced a significant improvement in carbohydrate metabolism through an increase in fractional hepatic insulin extraction (P < 0.05) and peripheral insulin sensitivity (P < 0.02) in normoinsulinemic women. HDL levels considerably increased, inducing an improvement in other atherosclerotic indexes, such as cholesterol/HDL and LDL/HDL ratios (P < 0.03). CONCLUSIONS: These results show that folic acid supplementation lowers plasma Hcy levels and improves insulin and lipid metabolism, reducing the risk of cardiovascular disease. 相似文献