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991.
Clinical significance of the assessment of endothelial function] 总被引:1,自引:0,他引:1
Stefano Taddei Lorenzo Ghiadoni Agostino Virdis Daniele Versari Antonio Salvetti 《Italian heart journal. Supplement》2004,5(5):357-365
Endothelium-derived nitric oxide is not only a potent vasodilator but also inhibits platelet aggregation, vascular smooth muscle cell migration and proliferation, monocyte adhesion and adhesion molecule expression, thus protecting the vessel wall from the development of atherosclerosis and thrombosis. Major cardiovascular risk factors are associated with endothelial dysfunction, which involves enhanced production of oxygen free radicals, that can destroy nitric oxide and reduce its availability, and release of endothelium-derived contracting factors including prostanoids and endothelin-1. Endothelial dysfunction is a promoter of atherosclerotic and thrombotic damage and in prospective studies on patients with high cardiovascular risk impaired endothelium-dependent vasodilation is associated with an increased incidence of cardiovascular events. However, endothelial function cannot yet be included among the surrogate endpoints which need to be measured for cardiovascular risk stratification. This limitation springs from the fact that available tests to assess endothelium-dependent vasodilation are invasive or, if noninvasive, they have no sufficient sensitivity and specificity to be proposed for clinical practice. Moreover, no study is available demonstrating that reversal of endothelial dysfunction, which can be obtained by appropriate treatment, is independently associated with a better clinical outcome. However it is conceivable that in the future, by the utilization of a non-invasive method such as the determination of brachial artery flow-mediated dilation, large-scale multicenter trials might provide a definitive answer to the real prognostic value of endothelial dysfunction, in terms of cardiovascular risk and therapeutic approach. 相似文献
992.
Vittoria Murro Andrea Sodi Lorenzo Vannozzi Cinzia De Libero Gabriele Simonini 《Ophthalmic genetics》2017,38(6):555-558
Purpose: To report a case of CRB1-associated retinal dystrophy characterized by vitritis, retinal capillaritis, and cystoid macular edema (CME).
Methods: A case report.
Results: An 8-year-old boy was diagnosed with intermediate uveitis and treated with corticosteroids. He was subsequently diagnosed with retinal dystrophy and found to have two CRB1 mutations.
Conclusions: Retinal capillaritis, vitritis, and CME could be inflammatory features of CRB1 retinal dystrophy in our young patient. 相似文献
993.
Rosa Della Monica Mariella Cuomo Roberta Visconti Annabella di Mauro Michela Buonaiuto Davide Costabile Giulia De Riso Teodolinda Di Risi Elia Guadagno Roberto Tafuto Sabrina Lamia Alessandro Ottaiano Paolo Cappabianca Maria Laura Del Basso de Caro Fabiana Tatangelo Juergen Hench Stephan Frank Salvatore Tafuto Lorenzo Chiariotti 《Oncology research》2020,28(9):837-845
Unresectable neuroendocrine neoplasms (NENs) often poorly respond to standard therapeutic approaches.
Alkylating agents, in particular temozolomide, commonly used to treat high-grade brain tumors including glioblastomas, have recently been tested in advanced or metastatic NENs, where they showed promising response
rates. In glioblastomas, prediction of response to temozolomide is based on the assessment of the methylation
status of the MGMT gene, as its product, O6
-methylguanine-DNA methyltransferase, may counteract the damaging effects of the alkylating agent. However, in NENs, such a biomarker has not been validated yet. Thus, we
have investigated MGMT methylation in 42 NENs of different grades and from various sites of origin by two
different approaches: in contrast to methylation-specific PCR (MSP), which is commonly used in glioblastoma
management, amplicon bisulfite sequencing (ABS) is based on high-resolution, next-generation sequencing
and interrogates several additional CpG sites compared to those covered by MSP. Overall, we found MGMT
methylation in 74% (31/42) of the NENs investigated. A higher methylation degree was observed in welldifferentiated tumors and in tumors originating in the gastrointestinal tract. Comparing MSP and ABS results,
we demonstrate that the region analyzed by the MSP test is sufficiently informative of the MGMT methylation
status in NENs, suggesting that this predictive parameter could routinely be interrogated also in NENs. 相似文献
994.
Malignant thymoma in children: a 20-year review 总被引:1,自引:0,他引:1
N Spigland M Di Lorenzo S Youssef P Russo M Brandt 《Journal of pediatric surgery》1990,25(11):1143-1146
Malignant thymomas are extremely rare in children, with only 27 cases reported thus far in the pediatric surgical literature. We report four additional cases diagnosed at this institution over the past 20 years (ages 3 to 14 years). Clinical presentations included superior vena cava syndrome, cough, dyspnea, cyanosis, enlarging mediastinal mass, spontaneous pneumothorax, and pleuropericardial effusion. Three patients underwent incomplete resection of the mass or biopsy because of "unresectability" and were treated with radiotherapy and adjunctive chemotherapy. One patient underwent near complete macroscopic resection as well as radiotherapy and chemotherapy. All patients died at intervals ranging from 6 months to 2 1/2 years after diagnosis. Three patients were found to have metastatic disease prior to death or at autopsy. In one case, the initial pathological diagnosis was lymphocytic thymoma. After ultrastructural studies were performed, the diagnosis was changed to thymic T-cell lymphoma. This patient subsequently developed acute lymphoblastic leukemia 3 months after surgical resection followed by radiotherapy. Malignant thymomas are highly aggressive tumors in children. A radical surgical approach with complete excision of the tumor and contiguous structures in continuity, with adjunctive radiotherapy and chemotherapy remains the only hope for survival in children with these rare lesions. 相似文献
995.
Julia Menke Kerstin Amann Lorenzo Cavagna Maria Blettner Arndt Weinmann Andreas Schwarting Vicki R. Kelley 《Journal of the American Society of Nephrology : JASN》2015,26(2):379-389
A noninvasive means to predict the onset and recurrence of lupus nephritis (LN) before overt renal injury is needed to optimize and individualize treatment. Colony-stimulating factor-1 (CSF-1) is expressed by kidney tubules at the onset of LN, increases with disease progression, and spills into the circulation in lupus-prone mice. We tested the hypothesis that amplified expression of CSF-1 detected in the serum or urine correlates with intrarenal CSF-1 expression and histopathology (increased macrophage accumulation, activity indices) and clinical kidney disease activity and predicts the onset and recurrence of nephritis in patients with systemic lupus erythematosus (SLE). We found increased serum or urine CSF-1 levels in patients with cutaneous, serositis, and musculoskeletal disease; however, the increase in CSF-1 levels was far greater in LN. Moreover, an elevation in serum or urine CSF-1 levels correlated with increasing intrarenal CSF-1 expression and histopathology. By longitudinally tracking patients, we found that elevated serum CSF-1 heralded the initial onset of disease, and a rise in serum or urine CSF-1 predicted recurrences of LN before clinical evidence of glomerular dysfunction and conventional serologic measures, even in patients with other manifestations of SLE. These findings indicate that serial monitoring for a rise in serum or urine CSF-1 levels in patients with SLE reflects kidney histopathology and may predict renal disease activity and the onset and recurrence of LN more accurately than conventional laboratory measures. 相似文献
996.
Masi G Cupini S Marcucci L Cerri E Loupakis F Allegrini G Brunetti IM Pfanner E Viti M Goletti O Filipponi F Falcone A 《Annals of surgical oncology》2006,13(1):58-65
Background The prognosis of unresectable metastatic colorectal cancer might be improved if a radical surgical resection of metastases
could be performed after a response to chemotherapy.
Methods We treated 74 patients with unresectable metastatic colorectal cancer (not selected for a neoadjuvant approach) with irinotecan,
oxaliplatin, and 5-fluorouracil/leucovorin (FOLFOXIRI and simplified FOLFOXIRI). Because of the high activity of these regimens
(response rate, 72%), a secondary curative operation could be performed in 19 patients (26%).
Results Four patients underwent an extended hepatectomy, nine patients underwent a right hepatectomy, three patients underwent a left
hepatectomy, and three patients had a segmental resection. In five patients, surgical removal of extrahepatic disease was
also performed. In seven patients, surgical resection was combined with intraoperative radiofrequency ablation. The median
overall survival of the 19 patients who underwent operation is 36.8 months, and the 4-year survival rate is 37%. The median
overall survival of the 34 patients who were responsive to chemotherapy, but who did not undergo operation, is 22.2 months
(P = .0114).
Conclusions The FOLFOXIRI regimens we studied have significant antitumor activity and allow a radical surgical resection of metastases
in patients with initially unresectable metastatic colorectal cancer not selected for a neoadjuvant approach and also those
with extrahepatic disease. The median survival of patients with resected disease is promising. 相似文献
997.
Lorenzo Fuccio Douglas Rex Thierry Ponchon Leonardo Frazzoni Mário Dinis-Ribeiro Pradeep Bhandari Evelien Dekker Maria Pellisè Loredana Correale Jeanin van Hooft Rodrigo Jover Diogo Libanio Franco Radaelli Sergio Alfieri Franco Bazzoli Carlo Senore Jaroslaw Regula Thomas Seufferlein Cesare Hassan 《Gastroenterology》2019,156(5):1309-1323.e3
998.
Francesco Leo Paolo Scanagatta Pierangelo Baglio Davide Radice Giulia Veronesi Piergiorgio Solli Francesco Petrella Lorenzo Spaggiari 《European journal of cardio-thoracic surgery》2007,31(5):780-782
OBJECTIVE: A higher mortality has been reported after pneumonectomy over the age of 70. The aim of the study was to quantify the additional risk due to age after standard pneumonectomy for lung cancer by a case-control study. METHODS: Our clinical database was reviewed to search for patients aged 70 years or more who underwent standard pneumonectomy for lung cancer between 1998 and 2005. A control group of patients younger than 70 (one case/two controls) was matched for sex, cardiovascular disease, American Association of Anaesthetists score, respiratory function, side of pneumonectomy, induction chemotherapy and stage. Overall mortality and morbidity were compared. Long-term survival data were also analysed. RESULTS: During the considered period, 35 patients aged 70 years or more underwent pneumonectomy (30 males, median age 73 years, 15 right-sided procedures). The control group was composed of 70 patients. The two groups were homogeneous in the variables used for matching. Overall mortality and morbidity were 11.4 and 54.2% in the elderly group as compared to 4.3 and 41.6% in controls (p-value not significant). Elderly patients experienced a higher rate of respiratory complications (25.7%) as compared to controls (8.3%, p=0.01). At univariate analysis, the only risk factor for death was the occurrence of respiratory complications (OR 6.5, CI 1.8-18.2). At multivariate analysis, age >or=70 years (OR 5.36, CI 1.48-19.3) and preoperative chemotherapy (OR 7.65, CI 2.04-28.6) were confirmed as predictors of respiratory complications. Five-year survival was 17.5% in the elderly group and 53.6% in the control group (p=0.003). Elderly patients with a better respiratory function (FEV1>70%) had a 5-year survival of 45.4%. CONCLUSIONS: In the elderly patients, the risk of respiratory complications after pneumonectomy is increased as compared to younger patients with equivalent respiratory function. Age and preoperative chemotherapy are independent risk factors for respiratory complications. A lower mortality and a better long-term survival are obtained in elderly patients with a better respiratory function (FEV1>or=70%). 相似文献
999.
M.D. Pereda C. Alonso L. Burgos-Asperilla J.A. del Valle O.A. Ruano P. Perez M.A. Fernández Lorenzo de Mele 《Acta biomaterialia》2010,6(5):1772-1782
Pure Mg has been proposed as a potential degradable biomaterial to avoid both the disadvantages of non-degradable internal fixation implants and the use of alloying elements that may be toxic. However, it shows excessively high corrosion rate and insufficient yield strength. The effects of reinforcing Mg by a powder metallurgy (PM) route and the application of biocompatible corrosion inhibitors (immersion in 0.1 and 1 M KF solution treatments, 0.1 M FST and 1 M FST, respectively) were analyzed in order to improve Mg mechanical and corrosion resistance, respectively. Open circuit potential measurements, polarization techniques (PT), scanning electrochemical microscopy (SECM) and electrochemical impedance spectroscopy (EIS) were performed to evaluate its corrosion behavior. SECM showed that the local current of attacked areas decreased during the F? treatments. The corrosion inhibitory action of 0.1 M FST and 1 M FST in phosphate buffered solution was assessed by PT and EIS. Under the experimental conditions assayed, 0.1 M FST revealed better performance. X-ray photoelectron spectroscopy, energy dispersive X-ray and X-ray diffraction analyses of Mg(PM) with 0.1 M FST showed the presence of KMgF3 crystals on the surface while a MgF2 film was detected for 1 M FST. After fluoride inhibition treatments, promising results were observed for Mg(PM) as degradable metallic biomaterial due to its higher yield strength and lower initial corrosion rate than untreated Mg, as well as a progressive loss of the protective characteristics of the F?-containing film which ensures the gradual degradation process. 相似文献
1000.
Mauro Giordano Tiziana Ciarambino Pietro Castellino Lorenzo Malatino Alessandro Cataliotti Luca Rinaldi Giuseppe Paolisso Luigi Elio Adinolfi 《The American journal of emergency medicine》2017,35(5):749-752