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We introduce a parametric dynamic factor specification for high-frequency financial data that simplifies considerably the estimation of the realized covariance matrix in high dimensions. The estimation method is tested in an empirical setting that emphasizes the effect of the curse of dimensionality. Compared to standard parametric approaches, our factor specification is computationally less demanding and provides statistically indistinguishable performances in standard risk management applications. The method is also assessed on Monte-Carlo simulations under several forms of misspecification. [ABSTRACT FROM AUTHOR]

Debris flows are among the most hazardous and unpredictable processes whose hazard evaluation requires an understanding of the processes that govern sediment supply, sediment bulking, flow volume, and deposition. In line with this challenge, we estimate the net soil redistribution rates in an area characterized by recurrent instability phenomena using Cs as a tracer for monitoring soil dynamics. An extension of this method by applying it to the case of major landslides is addressed. Specifically, surveys of soil Cs content at sites in the Pizzo d'Alvano massif (Italy), where a set of particularly damaging landslides occurred on 5-6 May 1998, are reported. Being this region prone to debris flows, two zero-order basins are examined, one of which experienced a landslide event. In that basin deposition is observed, whereas the other shows a net loss of soil. These results appear to be relevant, particularly because the rate of hollow filling could be correlated with the magnitude and/or frequency of debris flow occurrence or with some measure of the hazard presented by individual gullies. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine the prognostic significance of a high pretreatment serum CYFRA 21-1 level (a cytokeratin 19 fragment) adjusted for the effects of well-known co-variables in non-small-cell lung cancer (NSCLC). This meta-analysis based on individual updated data gathered comprehensive databases from published or unpublished controlled studies dealing with the prognostic effect of serum CYFRA 21-1 level at presentation in NSCLC of any stage (nine institutions, 2063 patients). Multivariate regression was carried out with the Cox model. The proportional hazard assumption for each of the selected variables retained in the final model was originally checked by log minus log plots baseline hazard ratio. The follow-up ranged from 25 to 78 months. A total of 1616 events were recorded. In the multivariate analysis performed at the 1-year end point, a high pretreatment CYFRA 21-1 level was an unfavourable prognostic determinant in all centres except one (Hazard ratio (95% confidence interval): 1.88 (1.64-2.15), P<10-4). Other significant variables were stage of the disease, age and performance status. Within the first 18 months, the procedure disclosed a nearly similar hazard ratio for patients having a high pretreatment serum CYFRA 21-1 level (1.62 (1.42-1.86), P<10-4). For patients who did not undergo surgery, the hazard ratio during the first year of follow-up was 1.78 (1.54-2.07), P<10-4. Finally, in the surgically treated population, at the 2-year end point, a high pretreatment CYFRA 21-1 and a locally advanced stage remained unfavourable prognostic determinants. In conclusion CYFRA 21-1 might be regarded as a putative co-variable in analysing NSCLC outcome inasmuch as a high serum level is a significant determinant of poor prognosis whatever the planned treatment.British Journal of Cancer (2004) 90, 2097-2105. doi:10.1038/sj.bjc.6601851 www.bjcancer.com Published online 4 May 2004 [ABSTRACT FROM AUTHOR]

A familial and personal history of cancer might be associated with a more aggressive cancerous disease. This study was carried out on 1277 consecutive lung cancer (LC) patients, seen from January 1989 to October 2002 in a single institution. A set of 31 clinical laboratory, radiological and pathological variables was recorded prospectively for all patients. In addition, both the number of first-degree blood-relatives with cancer (lung and non-lung cancers) and the personal history of previously cured cancers were noted. There were 368 patients (28.8% of the sample) who had one first-degree relative with cancer (112, 8.7% of the sample with LC), 100 (7.8%) had two first-degree relatives (six with LC) and 31 (2.4%) had three or more relatives affected (four with LC). In total, 1142 patients (89.4% of the sample) have never been treated for another cancer; the remaining 135 patients (10.6%) had already been diagnosed with a variety of tumours, including head and neck cancer (36 patients, 2.8%), bladder cancer (33 patients, 2.6%), colorectal cancer (24 patients, 1.9%), breast cancer (seven patients, 0.6%), melanoma (five patients, 0.4%), skin (five patients, 0.4%) and prostate cancer (five patients, 0.4%). Among the variables studied, none was found to be significantly associated with a personal and/or family history of cancer. Survival expectancy was similar among patients with or without a familial or personal history of cancer. A familial and a personal history of cancer are common features in LC, but are not of clinical significance. [ABSTRACT FROM AUTHOR]

Study Objectives: We have longstanding experience with tissue polypeptide antigen (TPA), a tumor marker of the cytokeratin (CK) family. In the mid-1990s, a new CK marker, CK 19 fragments (CYFRA 21-1), became popular and widely accepted. This is the first study specifically designed to compare the two markers.Design: Analysis of a single institution database over a 3-year period (ie, 1998 to 2000).Setting: Community-based hospital and second referral level institution for a province of 500,000 people.Patients: The study included 180 new consecutive patients (143 men) with pathologically documented non-small cell lung cancer (NSCLC), who were observed during and after treatment, and eventually were assessed for status.Interventions: Anthropometric, clinical, and laboratory data, including TPA and CYFRA 21-1 serum levels, were recorded prospectively. Standard nonparametric tests, Kaplan-Meyer survival analyses, Cox proportional hazards models, receiver-operating characteristic (ROC) curves, and estimates were used for statistical analysis.Measurements and Results: A total of 1,299 twin TPA and CYFRA 21-1 serum assays (180 performed at diagnosis and 1,119 performed during or after treatment) were obtained. Intermarker correlation tests revealed incredibly high Spearman rho indexes, ranging from 0.935 at diagnosis to 0.813 to 0.921 at the different follow-up times. The substantial equivalence of the two tests explained all the other results, as follows: their similar profile of correlation with the other variables (objective treatment response: TPA rho, 0.456; CYFRA 21-1 rho, 0.463; follow-up performance status: rho range, 0.424 to 0.435); their superimposable capability to predict important clinical situations (eg, recognizing a metastatic disease at diagnosis with areas under the ROC curve of 0.742 and 0.706, respectively); their nearly identical prognostic significance (the D statistic of the goodness-of-fit of a multivariate survival model: TPA, 851.0; CYFRA 21-1, 851.6).Conclusions: In most of their traditional clinical applications the two serum tests are equivalent because of their virtual identity. We strongly recommend using a CK test in the evaluation of each NSCLC patient. The choice between TPA and CYFRA 21-1 can be based on nonclinical factors, such as the laboratory experience or preference, and the cost of the two kits. [ABSTRACT FROM AUTHOR]

Several substances mark the course of lung cancer and may reliably help the clinician in decision-making. This is the first clinical study specifically designed to compare tissue polypeptide antigen and CA 125 tumour associated antigen. Three hundred and eighty-four new lung cancer patients (309 males) were studied at their first clinical presentation and then strictly followed-up. Anthropometric, clinical and laboratory data - including tissue polypeptide antigen and CA 125 tumour associated antigen serum levels - were prospectively recorded. A total of 1000 tissue polypeptide antigen and CA 125 tumour associated antigen serum assays (384 pre-treatment and 616 posttreatment assays) were performed. Both tissue polypeptide antigen and CA 125 tumour associated antigen correlated significantly with the T, N and M stage descriptors at diagnosis (Rho: 0.200, 0.203, 0.263 and 0.181, 0.240, 0.276, respectively), and then with the objective response to treatment (Rho: 0.388 and 0.207, respectively). A pleural neoplastic involvement was mainly associated to an increase of CA 125 tumour associated antigen (Rho: 0.397). Both tissue polypeptide antigen and CA 125 tumour associated antigen were strongly predictive of the patients' outcome, as assessed by the univariate analysis of survival (log-rank test: 37.24 and 29.01) and several Cox' proportional hazards regression models. The two marker tests are similarly helpful and appear complementary, given the low inter-marker correlation and their independent prognostic capability. [ABSTRACT FROM AUTHOR]

There is evidence that malnutrition is an important cause of morbidity and mortality in lung cancer patients and may have an impact on the clinical course of disease. The simplest way to assess nutritional status at the patient's bedside remains recourse to anthropometric measurements. This study was carried out in order to assess the clinical and prognostic significance of triceps skinfold thickness (TST), arm circumference (AC), and wrist circumference (WC) in lung cancer. The patient population was a consecutive series of 388 patients seen for a newly diagnosed primary non-small-cell lung cancer during the last 4 years. A set of 22 anthropometric, clinical, physical, laboratory, radiological, and pathological variables was prospectively recorded for all patients. Patients were carefully followed up, and their subsequent clinical course was recorded. The median values of TST, WC and AC were 8 mm (range 2-25 mm), 18 cm (range 10-27 cm), and 25 cm (range 15-35 cm), respectively. In 107 patients (27.6% of the total) TST values were below the reference value, and 37 of these patients also had a pathologically low small circumference. In all, AC was below the normality range in 60 of the 388 subjects (15.5%). Among the three variables, the strongest relationships were those between AC and WC (r(s)=0.541), and between TST and AC (r(s)=0.521). Univariate analyses of survival showed that TST was strongly predictive of a better prognosis (P<0.001), while WC was unrelated to outcome (P=0.101). Patients with higher values of AC had significantly longer survival than patients with lower values (P<0.018). The multivariate model, in contrast, did not confirm the prognostic capability of any of the anthropometric measures. These data indicate that the anthropometric measures may be significant predictors of survival, although not independently of the other prognostic factors. [ABSTRACT FROM AUTHOR]

Background: Thoracic computed tomography (CT) provides most of the staging information needed before operation for lung cancer and can reduce the number of exploratory thoracotomies. In recent years a new immunoscintigraphic technique with anti-carcinoembryonic antigen (CEA) monoclonal antibodies has been shown to be effective in lung cancer staging. This study compares the yields of CT scans and immunoscintigraphy in the preoperative evaluation of the medistinal lymph nodes of patients with non-small cell lung cancer.Methods: One hundred and thirty one patients believed on clinical grounds to have a operable non-small cell lung cancer were photoscanned with the indium-111 labelled F(ab')2 fragments of the antibody FO23C5. Both planar and single photoemission computed tomography (SPECT) thoracic views were recorded. CT scan of the thorax, abdomen, and brain were obtained in all patients. Seventy of the patients eventually underwent surgery, an additional seven underwent mediastinoscopy or mediastinotomy, and a further 10 had both cervical exploration and thoracotomy. Pathological evaluation of the mediastinal nodes was available in all 87 patients, but in only 80 of them was the diagnosis of lung cancer eventually confirmed.Results: The diagnostic accuracy of planar immunoscintigraphy, SPECT immunoscintigraphy, and CT scanning for N2 disease was 76%, 74%, and 71%, respectively. The corresponding sensitivity and specificity rates were 45%, 77%, 64% and 88%, 72%, and 74%. These were not significantly different.Conclusions: This study shows that anti-CEA immunoscintigraphy has no advantage over conventional CT scanning in assessing mediastinal lymphoadenopathy in patients with lung cancer. CT scanning remains the gold standard test in these patients. [ABSTRACT FROM AUTHOR]

The effects of propranolol 80 mg orally were compared with those of placebo on the response to a stepwise increasing exercise test in 17 healthy and physically untrained volunteers, of whom eight were female. Propranolol showed no significant effects on maximum work rate or perceived exertion rate. However, submaximal O2 uptake, CO2 output and minute ventilation tended to be lower after propranolol than after placebo. It is concluded that in subjects with a low work capacity, beta-adrenoceptor blockade does not impair maximal exercise capacity. The mechanisms underlying changes in respiratory response to exercise after propranolol are not fully explained. However, changes in substrate utilisation, the reduction in cardiac output and an alteration in respiratory drive may all be involved. [ABSTRACT FROM AUTHOR]

The article presents a preliminary study on the XVIth century cemetery of Castel San Pietro in Bologna, Italy as of January 2012. Also cited are the excavation activities by the Soprintendenza per i Beni Archeologici dell-Emilia Romagna and the Gruppo per la Valorizzazione della Valle del Sillaro in the late 1990s, which resulted in the discovery of a late antiquity basilical structure transformed during the Early Middle Ages.

Cardiovascular disease (CVD) is a major cause of morbidity and mortality in patients with chronic kidney disease (CKD), especially in end-stage renal disease (ESRD) patients and during the first year after transplantation. For these reasons, and due to the shortage of organs available for transplant, it is of utmost importance to identify patients with a good life expectancy after transplant and minimize the transplant peri-operative risk. Various conditions, such as severe pulmonary diseases, recent myocardial infarction or stroke, and severe aorto-iliac atherosclerosis, need to be ruled out before adding a patient to the transplant waiting list. The effectiveness of systematic coronary artery disease (CAD) treatment before kidney transplant is still debated, and there is no universal screening protocol, not to mention that a nontailored screening could lead to unnecessary invasive procedures and delay or exclude some patients from transplantation. Despite the different clinical guidelines on CAD screening in kidney transplant candidates that exist, up to today, there is no worldwide universal protocol. This review summarizes the key points of cardiovascular risk assessment in renal transplant candidates and faces the role of noninvasive cardiovascular imaging tools and the impact of coronary revascularization versus best medical therapy before kidney transplant on a patient's cardiovascular outcome.

Coronary artery aneurysm (CAA) is an abnormal dilatation of a coronary artery segment; those coronary artery aneurysms that are very large in size are defined as giant. However, a standardized dimension cut-off to define giant CAAs is still missing. The reported prevalence of coronary aneurysms in the population who underwent coronary angiography ranges from 0.3% to 5%, and often CAAs are found in patient with aneurysms in other sites, such as the ascending or abdominal aorta. In half of the cases an atherosclerotic etiology could be recognized; often, CAA is found in the context of acute coronary syndrome. Seldomly, CAA is found at the autopsy of patients who died due to sudden cardiac death. Currently, very few data exist about CAA management and their prognostic relevance; moreover, CAA treatment is still not clearly codified, but rather case-based. Indeed, currently there are no published dedicated studies exploring the best medical therapy, i.e., with antiplatelets or anticoagulant agents rather than an interventional approach such as an endovascular or surgical technique. In this review, through two clinical cases, the current evidence regarding diagnostic tools and treatment options of CAAs will be described.