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Two groups of 30 outpatients took part in a 3-month study designed to compare the efficacy and tolerability of the dihydropyridine calcium antagonists amlodipine and nifedipine retard in patients with mild to moderate essential hypertension. Data from 24-hour ambulatory blood pressure monitoring confirmed that both drugs produced good blood pressure control, although more significant and persistent reductions were observed in amlodipine recipients. This superiority may be due to the sustained plasma concentrations produced by this drug. Patients treated with amlodipine also experienced fewer adverse events than the nifedipine group.

Ground-based Fourier Transform Spectrometer observations in the infrared, acquired during the Italian phase of the EAQUATE campaign, have been considered in this study and compared to calculations. Synthetic spectral radiances have been obtained using the 2000 and 2004 releases and the 2006 upgrade of HITRAN spectral databases. It has been found that synthetic radiance computations fit the data quite well, even though the goodness of the fit depends on the spectral database. Differences in the spectral residual behaviour appear to be mostly localized in the long-wave side of the Earth emission spectrum, i.e. in the spectral region 520-610 cm(-1), which is dominated by the water vapour rotational absorption band. In this range, computation performed with the latest updates provides almost the same results as those of HITRAN2000, while HITRAN2004 shows a mixed behaviour - better than the first two in a large region of the spectral range, but worse at very few specific wave numbers. Overall, HITRAN2006 yields the highest consistency with the observations. No sensitive differences appear at higher wave numbers.

Direct solar irradiance and IR atmospheric radiance have been measured during different measurements campaigns, conducted in three mountain sites in Italy, far from anthropogenic sources. Direct solar irradiance has been measured by a high resolution (1.5 nm) AVANTES radiometer, working in the spectral range 400 nm-900 nm, while down welling IR sky radiance measurements has been measured by an MR100 BOMEM Fourier Transform Spectrometer covering the spectral ranges 500 cm-1-5000 cm-1 and 1 cm-1 of resolution. At least two Radiosonde launches per day furnished temperature and water vapour profiles. The instruments were located on a mobile laboratory, specifically projected to host them. The parameters obtained from direct solar irradiance are Aerosol Optical Depth, Angstrom parameters and Aerosol Size Distributions retrieval, while from IR data water vapour and temperature profiles have been retrieved. Different orographic characteristics and different air-masses circulation on the measurement sites influenced Aerosol Optical Depth values and variation. Infrared radiances inversion allows the water vapour content retrieval and a correlation between aerosol effective radii and water vapour content has been looked for.

Calcitonin gene-related peptide (CGRP) is a neuropeptide with potent cardio vascular effects that include positive inotropic and chronotropic actions systemic vasodilation, and hypotension in animals and in man. The mechanism of action of CGRP is still, however, not clear, and in particular it is not known whether vasodilation by CGRP occurs by changes in cutaneous or in muscular blood flow, or both. The aim of the study was, therefore, to evaluate the cutaneous and muscular blood flow, at rest and after ischemic test, induced by an IV bolus 25 μg human CGRP infusion in 5 healthy normotensive volunteers, using a strain gauge plethysmographic procedure with venous occlusion. Human CGRP pro voked a transient but significant decrease in sistolic and diastolic blood pressure, associated with tachycardia, marked flushing, a significant increase in plasma noradrenaline, adrenaline, and cyclic AMP levels, and a slight, but significant, decrease in serum total calcium. Moreover, a significant increase in the carpal cutaneous blood flow at rest was observed, with no significant change in the lower extremity muscular blood flow at rest and after ischemic test. Finally human CGRP produced a significant increase in the venous partial 02 pressure and in the hematocrit and a significant decrease in the venous partial CO2 pressure. The results of the present study confirm the acute cardiovascular and meta bolic effects of CGRP. In fact, hypotension, tachycardia, flushing, and the increased cutaneous blood flow indicate a systemic vasodilation by the neuropep tide, with a secondary sympathetic response, as documented by the augmented catecholamine and cyclic AMP plasma levels. Moreover, the plethysmographic study suggests a blood flow redistribution, from the muscular tissues to the cutaneous surface, with a relative lower oxygen uptake and CO2 release and a partial hemoconcentration phenomenon. In conclusion, these results are in agreement with the hypothesis that the vasodilative action of human CGRP is stronger on the skin than on the muscles of the lower extremities, even if a concomitant involvement of other vascular beds such as the splanchnic territory, by CGRP, cannot be excluded.

Eleven centers in Tuscany, Italy, recruited 96 patients (aged 21-75 years) with mild-to-moderate essential hypertension [diastolic blood pressure (DBP) 95-115 mm Hg; systolic blood pressure (SBP) less than or equal to 200 mm Hg]. After a 4-week, single-blind, placebo run-in period, patients received lacidipine 4 mg once daily. If blood pressure was not controlled after 1 month (control = DBP less than or equal to 90 mm Hg, or less than or equal to 95 mm Hg if reduced by greater than or equal to 15 mm Hg from baseline), the dose was increased to lacidipine 8 mg once daily. Atenolol 50 mg once daily was added after 2 months' monotherapy, if required for blood pressure control. The study continued for 13 months. About 40% of patients were titrated to 8 mg lacidipine; only 7% required addition of atenolol. Lacidipine significantly reduced blood pressure, with 84% of patients showing control of pressure values 24 h after the previous dose on completion of 5 months' monotherapy (63% controlled with lacidipine 4 mg/day; 21% with lacidipine 8 mg/day). There was no clinically relevant difference in the first-dose effect between the two doses of lacidipine (4 mg and 8 mg); both smoothly reduced blood pressure, with maximum effect after 2 h. Lacidipine was well tolerated. Adverse events were those expected with dihydropyridines, were mainly mild and occurred early, disappearing without discontinuation of treatment. Results indicate that 4-8 mg of lacidipine, administered once daily, is effective and well tolerated in mildly to moderately hypertensive patients.