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Identifying active galactic nuclei (AGN) and isolating their contribution to a galaxy's energy budget is crucial for studying the co-evolution of AGN and their host galaxies. Brightness temperature ($T_b$) measurements from high-resolution radio observations at GHz frequencies are widely used to identify AGN. Here we investigate using new sub-arcsecond imaging at 144 MHz with the International LOFAR Telescope to identify AGN using $T_b$ in the Lockman Hole field. We use ancillary data to validate the 940 AGN identifications, finding 83 percent of sources have AGN classifications from SED fitting and/or photometric identifications, yielding 160 new AGN identifications. Considering the multi-wavelength classifications, brightness temperature criteria select over half of radio-excess sources, 32 percent of sources classified as radio-quiet AGN, and 20 percent of sources classified as star-forming galaxies. Infrared colour-colour plots and comparison with what we would expect to detect based on peak brightness in 6 arcsec LOFAR maps, imply that the star-forming galaxies and sources at low flux densities have a mixture of star-formation and AGN activity. We separate the radio emission from star-formation and AGN in unresolved, $T_b$-identified AGN with no significant radio excess and find the AGN comprises $0.49\pm 0.16$ of the radio luminosity. Overall the non-radio excess AGN show evidence for having a variety of different radio emission mechanisms, which can provide different pathways for AGN and galaxy co-evolution. This validation of AGN identification using brightness temperature at low frequencies opens the possibility for securely selecting AGN samples where ancillary data is inadequate., Accepted for publication in MNRAS. 19 pages, 15 figures, 2 tables

BACKGROUND The aim of this study was to investigate the effects of vitamin D (VD) on the interaction among functional, echocardiographic and hormonal parameters in patients with heart failure (HF) and VD deficiency. METHODS In a randomized, double blind trial, 35 patients with HF and VD

Objectives To evaluate if screening and treatment of asymptomatic coronary artery disease (CAD) are effective in preventing first cardiac event in diabetics. Methods Diabetic patients without known CAD were randomly assigned to undergo a screening for silent myocardial ischemia followed by revascularization or to continue follow-up. The reduction of cardiac death (CD) or nonfatal myocardial infarction (MI) represented the primary aim; secondary aim was the prevention of heart failure (HF). Results From September 2007 to May 2012, 520 patients (62 years; 104 female) were enrolled. Silent CAD was found in 20 of 262 patients (7.6%), revascularization was performed in 12 (4.6%). After a mean follow-up of 3.6 years 12 events (4.6%) occurred in the study group and 14 (5.4%) in the follow-up (HR = 0.849, 95% CI: 0.393–1.827, P = 0.678). The occurrence of first HF episode did not differ between groups: 2 (0.8%) in screened and 7 (2.7%) in follow-up (HR = 0.273, 95% CI: 0.057–1.314, P = 0.083). Subgroup analysis revealed a significantly lower HF episodes among patients with intermediate cardiovascular risk (Log rank P = 0.022). Additionally, when CD and MI were analysed within subgroups, a significant lower number of CDs was observed among older than 60 years ( P = 0.044). Conclusion Screening and revascularization of silent CAD in diabetics, failed to demonstrate a significant reduction in cardiac events and HF episodes. However, our data indicate that further research is warranted in patients older than 60 years and those with an intermediate cardiovascular risk. ClinicalTrials.gov NCT00547872.

Right ventricular (RV) function impacts the outcome in cardiac and pulmonary diseases such as heart failure, pulmonary hypertension, myocardial infarction, valvular, and congenital heart diseases. To our knowledge, simultaneous evaluation of left ventricular (LV) and RV systolic and diastolic echocardiographic indices in outpatients with clinically stable cardiovascular diseases has never been performed. Thus, we designed a prospective cohort study to define the prognostic power of these parameters. One hundred and sixty-three patients were submitted to transthoracic echocardiography with multiparametric and tissue Doppler evaluation of the following indices: ejection fraction, MAPSE, TAPSE, RV presystolic peak, LV and RV diastolic function, pulmonary artery systolic pressure, and functional mitral regurgitation. All these parameters and clinical variables (age, sex, and prior cardiovascular events) were entered in a multivariable Cox regression model. The primary end point was the occurrence of major cardiovascular events (MACEs) during the follow-up period. Twenty-one MACEs were observed; in the final multivariable Cox regression model only prior cardiovascular events (B 1.305, p 0.004, 95% CI 1.523–8.933), age (B 0.067, p 0.005, 95% CI 1.020–1.121), and TAPSE (B −1.065, p 0.026, 95% CI 0.135–0.883) were associated with MACEs. TAPSE, a simple and reproducible echocardiographic index, may be viewed as an early echocardiographic marker of heart involvement in atherosclerosis. We believe that TAPSE may be useful in clinical practice for risk stratification.

Background Coronary artery disease is the leading cause of morbidity and mortality in patients with type 2 diabetes. Screening for asymptomatic coronary artery disease with treatment by means of revascularization seems to be an appealing option for prevention. The utility of such a strategy has never been challenged in a randomized trial. Methods/Design In the present study a cohort of diabetic patients without any symptoms and without known coronary artery disease will be screened at two diabetes outpatients services. Those with intermediate or high risk (equal or greater than 10% according to the Italian risk chart) will be asked to participate and enrolled. They will be seen and followed in order to provide the best adherence to medical therapy. Half of the patients will be randomized to undergo an exercise tolerance testing while the other group will continue to be regularly seen at diabetes outpatients services. Best medical/behavioral therapy will be offered to both groups. Those patients with a positive exercise tolerance testing will be studied by coronary angiography and treated according to the severity of coronary lesions by percutaneous stenting or surgery. The objective of the study is to evaluate the efficacy of the screening strategy aimed at revascularization. A cost-effectiveness analysis will be performed at the end of the follow up. Discussion The study will provide useful information about prevention and treatment of diabetic patients at high risk of coronary events. It will be made clearer if detection of silent coronary artery disease has to be recommended and followed by treatment. Given the simplicity of the study protocol, it will be easily transferable to the real world. Trial registration (ClinicalTrials.gov): NCT00547872

The aim of this prospective cohort study was to determine the incidence of dalteparin bioaccumulation (measured using anti-Xa levels), and bleeding during thromboprophylaxis in elderly patients with renal failure who were admitted to hospital with an acute medical illness. Patients who met the criteria for being at high thromboembolic risk received dalteparin 5,000 IU subcutaneously once daily while the other patients (low risk) received 2,500 IU daily. Thromboprophylaxis was administered for at least 6 days. Anti-Xa activity was determined before the first dalteparin dose and again on day 6, 4 hours after the administration of the dalteparin dose. Bleeding was assessed daily. Compression ultrasonography was performed to identify any deep vein thromboses. There was no evidence of bioaccumulation on day 6 of therapy, irrespective of renal function. No episodes of major bleeding or venous thromboembolism occurred. Larger, randomized studies are warranted to confirm the safety of dalteparin in this patient population.

Mastocytosis is a rare clonal disease characterized by an abnormal proliferation of mast cells, which accumulate in one or several organ systems such as skin, bone marrow, liver, spleen, lymph nodes and gastrointestinal tract. The heterogeneity of the clinical presentation is typically related to different disease burdens in various tissues and symptoms due to the release of mast cell mediators. The diagnosis is often difficult and delayed. Here we describe the case of a 70-year old patient with a past history of drug-induced anaphylactic shock whose clinical presentation was dramatic and required intensive support: the diagnosis of systemic mastocytosis was reached after the exclusion of diseases more commonly encountered in routine clinical practice (e.g. stroke, pulmonary embolism).

Purpose: To investigate the effects of cholecalciferol administration to chronic heart failure (CHF) patients with low vitamin D (VD) levels on physical performance, echocardiographic and hormonal parameters. Methods: From March to December 2012, in a randomized, double blind, placebo-controlled trial, 33 patients (age 78±7 - M 15) with stable CHF, VD≤30ng/ml and GFR≥30ml/min (latitude 45N), received 300000 U of oral cholecalciferol plus 50000 U/month for six months (17) or placebo (16). The primary end point was distance at 6 minute walking test (6MWT) at three and six months, secondary end points were hormonal (PTH, Renin, BNP, FGF23) and echocardiographic (chamber size, systolic/diastolic function) changes. Results: After six months VD levels significantly rose in both groups even if treated group reached higher levels (38.2±7.0 vs 14.3±7.2). In treated group PTH drop significantly at third month (from 76.8±50.5 to 50.2±20.3 p.025), but not at sixth, and 6MWT improved at three months (from 210±104 mt to 225±94 mt p.033) but not at sixth. Echocardiographic and hormonal parameters were unchanged in both groups. Among treated patients improvement of 6MWT was positively related to baseline PTH (p.027) and negatively to GFR (p.030); this was not seen in placebo group. View this table: Conclusion: In CHF our scheme of VD supplementation produced transient improvement of 6MWT and PTH but not of echocardiographic and hormonal parameters. Due to relation of 6MWT changes and basal PTH in treated patients, it might be possible that a more restrictive patient selection (hyperPTH) and higher VD doses, driven by PTH levels, would produce better and longer results.

Objectives: To study the incidence of bleeding complications during thromboprophylaxis with dalteparin in patients with acute medical illness and renal failure. Design: Prospective, cohort study. Setting: Community Hospital. Main outcome: The primary safety outcome was the incidence of major and minor bleeding, while the primary efficacy outcomes were objectively verified symptomatic DVT, pulmonary embolism, and objectively verified asymptomatic DVT detected on routine compression ultrasonography. Secondary outcomes included anti-Xa heparin levels. Patients: 56 consecutives patients (29 males, age 77.86±10.27 y, 27 females, age 84.60±6,78 y) admitted with acute medical illness were considered for the study. Eligible patients were 18 years or older and had none of the following: hepatic failure (prothrombin time 75 y, 44 of 56, 78%, active cancer, 5 of 56, 8.9%, previous venous thromboembolism, 1 of 56, 1.8%) received a dose of 5.000 IU daily; the other 12 received 2.500 IU daily. Dalteparin was given at 8 am for 6 days. The timing of anti-Xa activity determination and of compression ultrasound examination of leg veins is shown in table 1. Methods Results: there was 1 case (1 of 56, 1.8%) of nose bleeding at the third day of treatment in a patient with moderate renal failure. The bled was easily stopped. None of the following variables: dose of dalteparin, age, sex, creatinine clearance, and anti-Xa activity when entered in a regression model were able to predict the hemorrhagic complication. There were no cases of venous thromboembolism. Though, peak anti-Xa activity was higher in patients with marked renal impairment, it never reached therapeutic levels (>0.5 IU/mL). anti-Xa activity at day 6 Conclusions: The modest (and not significant) increase in anti-Xa activity in patients with reduced creatinine clearance was not associated with a clinically apparent risk of bleeding. Thromboprophylaxis with dalteparin appears safe even in acutely ill medical patients with renal failure. day 0 Creatinine Clearance anti-Xa activity before Dalteparin CUS day 6 Creatinine Clearance anti-Xa activity 4 h after Dalteparin CUS CrCl >90 ml/min CrCl >89–60 ml/min CrCl >59–30 ml/min CrCl