23 research outputs found
Characterization of marble weathering through pore structure quantitative analysis
Y Stone weathering is strongly controlled by the intrinsic properties of the stone and by its use. Previous studies demonstrate that the response to natural or artificial ageing processes of the rocks seems to be strongly influenced by the pore structure of the stone. A better understanding of this phenomenon is provided by the study and characterization of porosity and of the pore structure at different degrees of alteration. The analysis of the evolution of the decay leads to the evaluation of the durability of marble in facades, and more generally in buildings, as well as for the protection and recovery of artistic and architectural heritage.In this paper, we apply a methodology for the geometrical characterization of the pore structure to quantify alteration induced by natural weathering on marble slabs. The approach is based on the application of a path-finding algorithm to 2D binary images representative of thin sections of marble at different degrees of alteration. Through the identification of the paths within the porous domain, the methodology allows the characterization of the pore structure in terms of pore radius distribution along the identified paths. Analysis of the results demonstrate a good agreement between the degree of alteration of the pore structure and the corresponding variation of the physical and mechanical properties of the rock samples under investigation
Application of an electronic nose coupled with fuzzy-wavelet network for the detection of meat spoilage
Food product safety is one of the most promising areas for the application of electronic noses. During the last twenty years, these sensor-based systems have made odour analyses possible. Their application into the area of food is mainly focused on quality control, freshness evaluation, shelf-life analysis and authenticity assessment. In this paper, the performance of a portable electronic nose has been evaluated in monitoring the spoilage of beef fillets stored either aerobically or under modified atmosphere packaging, at different storage temperatures. A novel multi-output fuzzy wavelet neural network model has been developed, which incorporates a clustering pre-processing stage for the definition of fuzzy rules. The dual purpose of the proposed modelling approach is not only to classify beef samples in the relevant quality class (i.e. fresh, semi-fresh and spoiled), but also to predict their associated microbiological population. Comparison results against advanced machine learning schemes indicated that the proposed modelling scheme could be considered as a valuable detection methodology in food microbiology
Comparative evaluation of seven resistance interpretation algorithms and their derived genotypic inhibitory quotients for the prediction of 48 week virological response to darunavir-based salvage regimens
Background: the darunavir genotypic inhibitory quotient (gIQ) has been suggested as one of the predictors of virological response to darunavir-containing salvage regimens. Nevertheless, which resistance algorithm should be used to optimize the calculation of gIQ is still debated. The aim of our study was to compare seven different free-access resistance algorithms and their derived gIQs as predictors of 48 week virological response to darunavir-based salvage therapy in the clinical setting.
Methods: patients placed on two nucleoside reverse transcriptase inhibitors\u200a+\u200a600/100 mg of darunavir/ritonavir twice daily \u200a\ub1\u200a enfuvirtide were prospectively evaluated. Virological response was assessed at 48 weeks. Darunavir resistance interpretation was performed according to seven different algorithms, of which two were weighted algorithms. Analysis of other factors potentially associated with virological response at 48 weeks was performed.
Results: fifty-six treatment-experienced patients were included. Overall, 35 patients (62.5%) had a virological response at 48 weeks. Receiver operator characteristic curve analysis showed that De Meyer's weighted score (WS) and its derived gIQ (gIQ WS) were the most accurate parameters defining virological response, and related cut-offs showed the best sensitivity/specificity pattern. In univariate logistic regression analysis, baseline log viral load (P = 0.028), optimized background score 65 2 (P = 0.048), WS >5 (P = 0.001) and WS gIQ 65 600 (P\u200a<\u200a0.0001) were independently associated with virological response. In multivariate analysis, only baseline log viral load (P = 0.008) and WS gIQ 65 600 (P < 0.0001) remained in the model.
Conclusions: in our study, although different resistance interpretation algorithms and derived gIQs were associated with virological response, gIQ WS was the most accurate predictive model for achieving a successful virological response
Average bioequivalence of single 500 mg doses of two oral formulations of levofloxacin: a randomized, open-label, two-period crossover study in healthy adult Brazilian volunteers
Metastasis to Subsegmental and Segmental Lymph Nodes in Patients Resected for Non-Small Cell Lung Cancer: Prognostic Impact.
BACKGROUND:
We investigated the prognostic significance of segmental and subsegmental (level 13 and 14) lymph nodes metastasis in patients with resected non-small cell lung cancer (NSCLC).
METHODS:
The pattern of lymph nodal metastasis was analyzed in 124 patients with pN1 NSCLC. Long-term outcomes were compared for 390 pN0, 124 pN1, and 82 pN2 consecutive patients submitted to planned pulmonary resection for NSCLC between 2000 and 2006. The pN1 status was stratified into 3 groups according to the highest level of lymph node involvement: level 10 (hilar); level 11+12 (lobar + interlobar); and level 13+14 (segmental + subsegmental).
RESULTS:
The 5-year overall survival (OS) rates for pN0, pN1, and pN2 patients were 93%, 66%, and 25%, respectively. The highest level of lymph node involvement was a significant prognostic indicator; the 5-year OS rate for level 13+14, level 11+12, level 10 pN1, and pN2 was 81%, 58%, 48%, and 25%, respectively. Significant differences were recorded in long-term outcome when pN0 and pN1 level 13+14, pN1 level 13+14, and pN1 level 11+12, pN1 level 11+12 and pN1 level 10 were compared (p < 0.05). The median number of examined level 13+14 lymph nodes was 2 (range 0 to 6) and 57% pN1 patients had metastasis at level 13+14 lymph nodes.
CONCLUSIONS:
The highest level of lymph node metastases may be used to stratify outcome of patients with pN1 disease. Routine examination of level 13+14 lymph nodes is to be recommended to correctly identify patients at risk of relapse and predict long-term prognosi
The solitary pulmonary nodule in patients with previous cancer history: Results of surgical treatment.
BACKGROUND:
The present study was carried out to evaluate the characteristics of solitary pulmonary nodule (SPN) in patients with previous cancer(s) and to analyse the outcome of its surgical treatment.
METHODS:
We retrospectively analysed 131 patients with history of previous malignancy submitted to lung surgery for new identified SPN between January 2004 and December 2009.
RESULTS:
The diagnosis was metastasis in 65 patients, primary lung cancer in 57, benign lesion in 9. Primary lung cancers were significantly larger, had higher maxSUV at CT-PET scanning, occurred after a longer disease-free interval in patients older and with worse lung function when compared with metastatic lesions. Overall survival at 5-year was 67% for benign lesions, 62% for primary lung cancer, 48% for metastatic disease. Histological subtype, SPN diameter less than 2 cm and DFI >36 months were factors influencing long-term prognosis of metastatic patients. Histological subtype and pathological staging were factors influencing long-term outcome of primary lung cancer patients.
DISCUSSION:
Surgical resection of solitary pulmonary nodule is essential in patients with history of previous cancer to rule out benign lesions, to offer diagnostic confirmation and local control of the disease in metastatic tumours and to correctly stage and treat primary lung cancer
Non-small cell lung cancer in surgically treated women.
AIM AND BACKGROUND: To determine whether female patients operated on for non-small cell lung cancer (NSCLC) have a survival advantage compared to male patients.
METHODS AND STUDY DESIGN: We analyzed data from 1,426 prospectively collected patients submitted to lung resection for NSCLC between 1999 and 2008.
RESULTS: Two groups, including 1,014 male and 412 female patients, were compared. Female patients were significantly younger, were more frequently asymptomatic, were less likely to be smokers, had better preoperative respiratory function, had a lower frequency of COPD, and were less commonly affected by cardiovascular comorbidity than men. Adenocarcinoma was more frequently present and early pathological stage (stage IA) more frequently detected in women at diagnosis. The operative mortality was significantly lower among women (1.6% vs 4.6%) (P = 0.012), and women underwent significantly more segmentectomies and fewer pneumonectomies (P = 0.001). The disease-related 5-year survival rate was significantly higher in women (66% vs 51%) (P = 0.0008). At univariate analysis the absence of symptoms at presentation, lower pathological stage, squamous cell type, and female gender were positive factors influencing long-term survival. At multivariate analysis low pathological stage, squamous cell type and female gender were confirmed as independent positive prognostic predictors. Women had a significant survival advantage irrespective of the histological subtype at pathological stage IA, IB, IIB and IIIA disease (P <0.05).
CONCLUSIONS: Female gender was confirmed to be a particular subset amongst patients affected by NSCLC and exerted a positive effect on disease-related survival of patients submitted to surgical resection. This important effect of gender should be cautiously kept in mind in analyzing the results of current and future trials for lung cancer therapy
Malignant pleural mesothelioma: Germline variants in DNA repair genes may steer tailored treatment
Malignant pleural mesothelioma: Germline variants in DNA repair genes may steer tailored treatment
Introduction: Malignant pleural mesothelioma (MPM) is a tumour associated with asbestos exposure. Approximately, 10% of patients with MPM carry a germline pathogenic variant (PV), mostly in DNA repair genes, suggesting the occurrence of inherited predispositions. Aim: This article aimed to 1) search for new predisposing genes and assess the prevalence of PVs in DNA repair genes, by next-generation sequencing (NGS) analysis of germline DNA from 113 unselected patients with MPM and 2) evaluate whether these patients could be sensitive to tailored treatments. Methods: NGS was performed using a custom panel of 107 cancer-predisposing genes. To investigate the response to selected drugs in conditions of DNA repair insufficiency, we created a three-dimensional-MPM cell model that had a defect in ataxia telangiectasia mutated (ATM), the master regulator of DNA repair. Results: We identified PVs in approximately 7% of patients with MPM (8/113) and a new PV in BAP1 in a further patient with familial MPM. Most of these PVs were in genes involved or supposedly involved in DNA repair (BRCA1, BRIP1, CHEK2, SLX4, FLCN and BAP1). In vitro studies showed apoptosis induction in ATM-silenced/inhibited MPM spheroids treated with an enhancer of zeste homologue 2 inhibitor (tazemetostat). Conclusions: Overall these data suggest that patients with MPM and DNA repair insufficiency may benefit from this treatment, which induces synthetic lethality