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Objective: In type 2 diabetes, prevalence of nonalbuminuric renal impairment is increasing worldwide, though its clinical significance remains unclear. This large-cohort study aimed at evaluating the association of this phenotype with cardiovascular risk factors and other complications. Methods: Type 2 diabetic patients from the Renal Insufficiency And Cardiovascular Events (RIACE) Italian Multicenter Study (n=15773), visiting consecutively 19 hospital-based Diabetes Clinics in years 2007-2008, were examined. Serum creatinine was assessed by the Jaffe method; albuminuria was measured by immunonephelometry or immunoturbidimetry. Results: Of patients with renal impairment, as identified by an estimated glomerular filtration rate (eGFR) less than 60ml/min per 1.73m, 56.6% were normoalbuminuric, 30.8% were microalbuminuric, and 12.6% were macroalbuminuric. Percentages were similar when GFR was estimated using the more accurate Chronic Kidney Disease Epidemiology Collaboration equation instead of the simplified Modification of Diet in Renal Disease formula, and were independent of age, thus indicating that the increasing prevalence of this phenotype does not reflects misclassification of elderly patients. Nonalbuminuric renal impairment was not associated with HbA1c and correlated less strongly with retinopathy and hypertension than albuminuria, either alone or associated with reduced eGFR. It was associated with a higher prevalence of cardiovascular disease (CVD) than albuminuria alone, but lower than albuminuric renal impairment. Female sex correlated with nonalbuminuric renal impairment and male sex with the albuminuric forms. Conclusion:S: These data show that type 2 diabetic patients with nonalbuminuric renal impairment exhibit distinct clinical features, suggesting predominance of macroangiopathy as underlying renal pathology, and that this phenotype is associated with significant CVD burden.

International Symposium Aquatic Mesocosm Research: Recent achievements and future directions in Aquatic Mesocosm Research, 16-19 October 2012, Heraklion, Crete, Greece

Summary Background Idiopathic pulmonary fibrosis is a fatal disease for which no effective treatment exists. We assessed whether treatment with interferon gamma-1b improved survival compared with placebo in patients with idiopathic pulmonary fibrosis and mild-to-moderate impairment of pulmonary function. Methods 826 patients with idiopathic pulmonary fibrosis were enrolled from 81 centres in seven European countries, the USA, and Canada. Patients were randomly assigned (double-blind) in a 2:1 ratio to receive 200 μg interferon gamma-1b (n=551) or equivalent placebo (n=275) subcutaneously, three times per week. Eligible patients were aged 40–79 years, had been diagnosed in the past 48 months, had a forced vital capacity of 55–90% of the predicted value, and a haemoglobin-corrected carbon monoxide diffusing capacity of 35–90% of the predicted value. The primary endpoint was overall survival time from randomisation measured at the second interim analysis, when the proportion of deaths had reached 75% of those expected by the study conclusion. This study is registered with ClinicalTrials.gov, number NCT00075998. Findings At the second interim analysis, the hazard ratio for mortality in patients on interferon gamma-1b showed absence of minimum benefit compared with placebo (1·15, 95% CI 0·77–1·71, p=0·497), and indicated that the study should be stopped. After a median duration of 64 weeks (IQR 41–84) on treatment, 80 (15%) patients on interferon gamma-1b and 35 (13%) on placebo had died. Almost all patients reported at least one adverse event, and more patients on interferon gamma-1b group had constitutional signs and symptoms (influenza-like illness, fatigue, fever, and chills) than did those on placebo. Occurrence of serious adverse events (eg, pneumonia, respiratory failure) was similar for both treatment groups. Treatment adherence was good and few patients discontinued treatment prematurely in either group. Interpretation We cannot recommend treatment with interferon gamma-1b since the drug did not improve survival for patients with idiopathic pulmonary fibrosis, which refutes previous findings from subgroup analyses of survival in studies of patients with mild-to-moderate physiological impairment of pulmonary function. Funding InterMune.

PURPOSE: The aim of this study was to evaluate the suitability of [11C]SCH442416 for the in vivo imaging of adenosine A2A receptors. METHODS: In rats and Macaca nemestrina, we evaluated the time course of the cerebral distribution of [11C]SCH442416. Furthermore, in rats we investigated the rate of metabolic degradation, the inhibitory effects of different drugs acting on adenosine or dopamine receptors and the modification induced by the intrastriatal administration of quinolinic acid (QA). RESULTS: The rate of metabolic degradation of [11C]SCH442416 in rats was slow; 60 min after tracer injection, more than 40% of total plasma activity was due to unmetabolised [11C]SCH442416. At the time of maximum uptake, radioactive metabolites represented only 6% of total extractable activity in the cerebellum and less than 1% in the striatum. In the striatum, the region with the highest expression of A2A receptors, the in vivo uptake of [11C]SCH442416 was significantly reduced only by drugs acting on A2A receptors or by QA, a neurotoxin that selectively reduces the number of intrastriatal GABAergic neurons. Position emission tomography (PET) studies in monkeys indicated that the tracer rapidly accumulates in brain, reaching maximum uptake between 5 and 10 min. Twenty minutes after the injection, radioactivity concentration in the striatum was two times that in the cerebellum. CONCLUSION: The specificity of binding, the rank order of regional distribution in the brain of rats and M. nemestrina, the good signal to noise ratios and the low amount of radioactive metabolites in brain and periphery indicate that [11C]SCH442416 is a promising tracer for the in vivo imaging of A2A adenosine receptors using PET.

The radiolabelling with the positron-emitter Carbon-11 and the biological evaluation in rats of3-[2-[4-(2-[11C]methoxyphenyl)piperazin-1-yl]ethyl] pyrimido[5,4-b]indole-2,4-dione([11C]RN5), a1-adrenoceptor antagonist (Ki= 0.21 nM), as a putative radioligand for the non-invasive assessment of alpha1-adrenoceptors with Positron Emission Tomography (PET) is reported. The radiosynthesis procedure consisted of O-methylation of des-methyl precursor with [11C]methyl iodide in the presence of potassium hydroxide in dimethylformamide (DMF) at 80°C. [11C]RN5 was obtained in >99% radiochemical purity in 25 min with a radiochemical yield in the 20-30% range, end of synthesis (EOS) (non-decay corrected) and a specific radioactivity of 92.5±18.5 GBq/mmol. Pre-clinical studies in rats showed a high uptake of [11C]RN5 in heart, spleen, adrenal gland, lung and kidney but not in the brain. Inhibition studies with high doses of different adrenergic antagonists indicate that more than 70% of myocardial uptake of [11C]RN5 is due to specific binding to alpha1-adrenoceptors. Our results indicate that [11C]RN5 is suitable to be further developed as a potential radioligand for the in vivo PET imaging of myocardial alpha1-adrenoceptors in humans.

The medical therapy of myocardial ischemia in elderly patients has not been well evaluated. We studied the age-related changes in 127 patients with proved coronary artery disease and stable effort angina the efficacy and the safety of diltiazem 120 mg tid, verapamil 120 mg tid and gallopamil 50 mg tid a medium term parallel, double blind cross-over placebo controlled study. All patients have been clinically and ergometrically evaluated. In middle-age patients diltiazem, verapamil and gallopamil induced a significant increasing of exercise duration and time to onset ST segment depressionor = 1 mm. In the elderly patients both verapamil and diltiazem as increased the exercise duration and ischemic threshold, while the diltiazem did not increased the exercise duration even if the time of onset ST segment depressionor = 1 mm is increased. At peak exercise the ST segment depression have been reduced both in middle-age and elderly patients after active drugs. Weekly angina and DNT consumption have been significantly reduced after diltiazem, verapamil and gallopamil in middle-age and elderly patients. Side effects have not been relevant even if gallopamil as a lower frequency of them in comparison to diltiazem and verapamil. No patients stopped the treatment because major side effects. Our experience suggests that diltiazem, verapamil and gallopamil have a similar efficacy and rare well tolerated. The choice of one instead of another must be suggested on the basis of side effects developing.

The selective dopamine D(3) receptor ligands N-4-[4-[(2,3-dichlorophenyl)piperazin-1-yl]butyl]1-methoxy-2-naphthalencarboxamide (1) and N-4-[4-[(2,3-dichlorophenyl)piperazin-1-yl]butyl]-7-methoxy-2-benzofurancarboxamide (2) were labeled with (11)C (t(1/2) = 20.4 min) as potential radioligands for the noninvasive assessment of the dopamine D(3) neurotransmission system in vivo with positron emission tomography (PET). The radiosynthesis consisted in an O-methylation of the des-methyl precursors N-[4-[4-(2,3-dichlorophenyl)piperazin-1-yl]butyl]-1-hydroxy-2-naphthalenecarboxamide (3) and N-[4-[4-(2,3-dichlorophenyl)piperazin-1-yl]butyl]-7-hydroxy-2-benzofurancarboxamide (4) with [(11)C]methyl iodide using tBuOK/HMPA and KOH/DMSO, respectively. The radiotracers [(11)C]1 and [(11)C]2 were obtained in 35 min with over 99% radiochemical purity, 74 +/- 37 GBq/mumol of specific radioactivity, 13% and 26% radiochemical yield (EOB, decay-corrected). Distribution studies in rats demonstrated that the new tracers [(11)C]1 and [(11)C]2 cross the blood-brain barrier and localize in the brain. However, the kinetics of cerebral uptake did not reflect the regional expression of the D(3) receptors. Despite their in vitro pharmacological profile, [(11)C]1 and [(11)C]2 do not display an in vivo behavior suitable to image D(3) receptor expression using PET.

The novel quinoline-2-carboxamide derivatives N-[methyl-C-11]-3-methyl-4-phenyl-N-(phenyl-methyl)quinoline-2-carboxamide ([C-11]4), (+/-)-N-[methyl-C-11]-3-methyl-N-(1-methylpropyl)-4- phenylquinoline-2-carboxamide ([C-11]5), and (+/-)-N-[methyl-C-11]-3-methyl-4-(2-fluorophenyl)-N-(1-methylpropyl)quinoline-2-carboxamide ([C-11]6) were labeled with carbon-11 (t(1/2) = 20.4 min, beta (+) = 99.8%) as potential radioligands for the noninvasive assessment of peripheral benzodiazepine type receptors (PBR) in vivo with positron emission tomography (PET). The radiosynthesis consisted of N-methylation of the desmethyl precursors 3-methyl-4-phenyl-N-(phenylmethyl)quinoline-2-carboxamide (4a), (+/-)-3-methyl-N-(1-methylpropyl)-4-phenylquinoline-2-carboxamide (5a), and (+/-)-4-(2-fluorophenyl)-3-methyl-N-(1-methylpropyl)quinoline-2-carboxamide (6a) with either [C-11]methyl iodide or [C-11]methyl triflate in the presence of tetrabutylammonium hydroxide or potassium hydroxide in dimethylformamide. The radioligands [C-11]4, [C-11]5, and [C-11]6 were synthesized with over 99% radiochemical purity in 30 min, 30 +/- 5% radiochemical yield, calculated at the end of synthesis (EOS) non-decay-corrected, and 2.5 +/- 1.2 Ci/mu mol of specific radioactivity. Inhibition studies in rats following intravenous pre-administration of 1-(2-chlorophenyl)-N-methyl-N-(1-methylpropyl)-3-isoquinolinecarboxamide (PK 11195, 1) showed high specific binding to PER of [C-11]4, [C-11]5, and [C-11]6 in heart, lung, kidney, adrenal gland, spleen, and brain. The biological data suggest that [C-11]5, [C-11]6, and particularly [C-11]4 are promising radioligands for PER imaging in vivo with PET.

We evaluated [ 11 C]fluvoxamine as a tracer for the serotonin re-uptake site. Studies of the distribution of the tracer in rat and primate brain showed adequate uptake of [ 11 C]fluvoxamine, but failed to reveal regions with known high density of serotoninergic re-uptake sites. Pretreatment with unlabeled fluvoxamine did not substantially change the distribution. In rat brain tissue, nearly all radioactivity represented intact [ 11 C]fluvoxamine. [ 11 C]Fluvoxamine does not function as a tracer for serotonin re-uptake sites, owing to high nonspecific binding in the brain.

The previous exploration of the structure-affinity relationships concerning 4-phenyl-2-quinolinecarboxamide peripheral benzodiazepine receptor (PBR) ligands 6 showed as an interesting result the importance of the presence of a chlorine atom in the methylene carbon at position 3 of the quinoline nucleus. The subnanomolar PBR affinity shown by N-benzyl-3-chloromethyl-N-methyl-4-phenyl-2-quinolinecarboxamide (6b) suggested its chlorine atom to be replaced with other halogens in order to optimize the interaction of the quinolinecarboxamide derivatives with PBR and to develop suitable candidates for positron emission tomography (PET) or single photon emission computed tomography (SPECT) studies. The binding studies led to the discovery of fluoromethyl derivative 6a, which showed an IC(50) value of 0.11nM and is, therefore, one of the most potent PBR ligands so far described. Fluoromethyl derivative 6a has been labeled with (11)C (t(1/2)=20.4min, beta(+)=99.8%) starting from the corresponding des-methyl precursor (14) using [(11)C]CH(3)I in the presence of tetrabutylammonium hydroxide in DMF with a 35-40% radiochemical yield (corrected for decay) and 1.5Ci/mumol of specific radioactivity. Ex vivo rat biodistribution and inhibition (following intravenous pre-administration of PK11195) studies showed that [(11)C]6a rapidly and specifically accumulated in PBR-rich tissues such as heart, lung, kidney, spleen, and adrenal, and at a lower level in other peripheral organs and in the brain. The images obtained in mouse with small animal YAP-(S)PET essentially confirmed the result of the ex vivo biodistribution experiments. The biological data suggest that [(11)C]6a is a promising radioligand for peripheral benzodiazepine receptor PET imaging in vivo.

The radiolabelling with the positron-emitter Carbon-11 and the biological evaluation in rats of 3-[2-[4-(2-[C-11]methoxyphenyl)piperazin-1 -yl]ethyl] pyrimido [5,4-b] indole-2,4-dione ([C-11]RN5), alpha(1)-adrenoceptor antagonist (K-i = 0.21 nM), as a putative radioligand for the noninvasive assessment of alpha(1)-adrenoceptors with positron emission tomography (PET) is reported. The radiosynthesis procedure consisted of O-methylation of des-methyl precursor with [C-11]methyl iodide in the presence of potassium hydroxide in dimethylformamide (DMF) at 80 degreesC. [C-11]RN5 was obtained in >99% radiochemical purity in 25 min with a radiochemical yield in the 20-30% range, end of synthesis (EOS) (non-decay corrected) and a specific radioactivity of 92.5 18.5 GBq/mumol. Pre-clinical studies in rats showed a high uptake of [C-11]RN5 in heart, spleen, adrenal gland. lung and kidney but not in the brain. Inhibition studies with high doses of different adrenergic antagonists indicate that more than 70% of myocardial uptake of [C-11]RN5 is due to specific binding to alpha(1)-adrenoceptors. Our results indicate that [C-11]RN5 is suitable to be further developed as a potential radioligand for the in vivo PET imaging of myocardial alpha(1)-adrenoceptors in humans. (C) 2002 Published by Elsevier Science B.V

(+/-)-1-[4-(2-Isopropoxyethoxymethyl)-phenoxy]-3-isopropylamino-2-propanol (bisoprolol) is a potent, clinically used beta(1)-adrenergic agent. (R)-(+) and (S)-(-) enantiomers of bisoprolol were labelled with carbon-11 (t(1/2)=20.4 min) as putative tracers for the non-invasive assessment of the beta(1)-adrenoceptor subtype in the human heart and brain with positron emission tomography (PET). The radiosynthesis consisted of reductive alkylation of des-iso-propyl precursor with [2-11C]acetone in the presence of sodium cyanoborohydride and acetic acid. The stereo-conservative synthesis of (R)-(+) and (S)-(-)-1-[4-(2-isopropoxyethoxymethyl)-phenoxy]-3-amino-2-propanol to be used as the precursors for the radiosynthesis of [11C]bisoprolol enantiomers was readily accomplished by the use of the corresponding chiral epoxide in three steps starting from the commercially available hydroxybenzyl alcohol. The final labelled product (either (+) or (-)-1-[4-(-isopropoxyethoxymethyl)-phenoxy]-3- [11C]isopropylamino-2-propanol) was obtained in 99% radiochemical purity in 30 min with 15+/-5% (EOS, non-decay corrected) radiochemical yield and 3.5+/-1 Ci/micromol specific radioactivity. Preliminary biological evaluation of the tracer in rats showed that about 30% of heart uptake of [11C](S)-bisoprolol is due to specific binding. The high non-specific uptake in lung might mask the heart uptake, thus precluding the use of [11C](S)-bisoprolol for heart and lung studies by PET. The remarkably high uptake of the tracer in rat brain areas rich of beta-adrenergic receptors such as pituitary (1.8+/-0.3% I.D. at 30 min) was blocked by pre-treatment with the beta-adrenergic antagonists propranolol (45%) and bisoprolol (51%, p

Erytro-(+/-)-1-[2,3-(dihydro-7-methyl-1H-inden-4-yl)oxy]-3-[ iso-propylamino]-2-butanol (ICI 118551) a potent clinically used beta2 adrenergic antagonist, was labelled with carbon-11 (t1/2 = 20.4 min) as a potential radioligand for the non-invasive assessment of beta2 adrenergic receptors in the lung with positron emission tomography (PET). The radiolabelled compound was prepared by reductive N-alkylation of its des-isopropyl precursor with [2-11C]acetone. (+/-)-[11C]ICI 118551 was obtained in greater than 98% radiochemical purity in 30 min with a radiochemical yield of 15 + 5% (non-decay corrected) and a specific radioactivity 2.5 +/- 0.5 Ci/micromol. The biological evaluation of racemic erythro (+/-)-[11C]ICI 118551 in rats and Macaca Nemestrina shows a high radioactivity uptake in lung and heart. However, in both animal models no detectable displacement of lung radioactivity concentration was observed after pre-treatment with propranolol or ICI 118551, which indicates that in this organ, radioligand uptake is mostly due to non-specific binding. The biological data suggest that erythro (+/-)-[11C]ICI 118551 is not adequate to be further developed as a tracer for beta2 adrenergic receptor imaging in vivo.