Two tectono-sedimentary domains, which were deformed during the Neogene and evolved into two large structural sectors, characterize the Sicilian Jurassic: the Maghrebides and Peloritani. Africa margin sediments, passing downward to Triassic successions and perhaps originally to Paleozoic deposits, characterize the former. The latter belongs to the European "Calabrian Arc", where the Jurassic transgressively rests on a continental substrate (i.e. the crystalline Variscan basement). These domains are characterized by four sedimentary facies: shallow platform-derived limestones; condensed seamount-type red limestones; nodular limestones with ammonites; deep radiolarites and shales. These facies are illustrated in a dozen of stratigraphic logs. The drowning of most Triassic-Liassic carbonate platforms or ramps and the deepening of adjacent basins came with inferred Jurassic strike-slip tectonics, connected to the relative movement of Africa (Gondwanan part) vs Europe (Laurasian part); the same strike-slip tectonics may have caused scattered intraplate volcanic seamounts found in Maghrebides. During the Jurassic the Maghrebide realm was characterized by the interfingering of basins and carbonate platforms. During the Early and Middle Liassic, carbonate platforms and ramps were dominant. Since Toarcian either radiolarites in some basins or Ammonite-bearing calcareous muds developed with intervening basaltic flows, and were accompanied by condensed pelagic carbonates on the ensialic seamount-type highs. The Peloritani realm displays similar characteristics, but with later transgression on the basement, several strike-slip basins and without any volcanoes.

They are: Reichelina sp., Schubertella paralnelonica, Toriyamaia (?) sp., Neofusidinella Iantenoisi, Yangchienia compressa, Rauserella staffi, Darvasites contractus, Chalaroschwagerina (Taiyuanella?) aff. davalensis, Levenella aff. evoluta, Pamirina darvasica, and Neoschwagerina ex gr. craticulifera. Small Permian foraminifers, as well as the calcispherid Asterosphaera pulchra also exist. The microfossils indicate reworking of different Permian stages, at different periods of time, and possibly also of the Mississippian (Early Carboniferous). All these resediments have been deposited within the Lercara Formation, a series definitely belonging to the Triassic period. Therefore. due to this reworking, Sicily appears as a controversial area for establishing biostratigraphic and palaeobiogeographic correlations in the Permian period. (C) 2004 Academie des sciences. Published by Elsevier SAS. All rights reserved.

The area of the Longi-Galati-S. Salvatore di Fitalia-Frazzano quadrangle in the Peloritani chain, already the subject of about ten conflicting chartographic interpretations, presents several different stratigraphic successions of the basement's cover, in spite of its limited areal extent. Analysis of these successions and comparison between them ad with those of neighbouring and distant zones has allowed a reconstruction of the palaeophysiography and of the facies palaeodomains and their original locations. During Early and Middle Liassic times the palaeodomains were characterised by physiographic and structural evolution, which forced them around rhombocasms from possible transtensions (e.g. the palaeodomain of Longi) surrounded by carbonate platforms. In the Middle Jurassic the platforms (e.g. of Galati) were drowned to become ensialic seamounts with condensed pelagic sedimentation; in the Late Cretaceous, following the sharp rotation of the Africa v/s Europe drift direction, «push-ups» and/or «flowers» structures developed; subsequent detachment of megabreccias, which were deposited in the adjacent depressions, and sedimentation of Scaglia occurred simultaneously. During the Early to Middle Miocene, the change in compressional regime from Alpine to Mediterranean (specifically to the Ionian trend related to emplacement of the whole Calabrian Arc) caused overthrusting of the materials of the mesozoic palaeodomains, in a system of three Nappes and two secondary tectonic units, respectively Galati, Longi, Fondachelli-Maudrazzi and Frazzano and P.so d'Armi. These units were thrust on to the Mesozoic-Cenozoic Argille Varicolori of the Sicilide domain. The Fondachelli-Mandrazzi Nappe would at least have supplied the detritus for the Oligocene-Aquitanian Frazzano Flysch on the palaedomain of Longi; the Aspromonte Nappe - probably already in place outside the Longi area - would have supplied the detritus for the so called Capo d'Orlando Flysch molasse that mantles previously emplaced nappes. The position of the «Sicilidi» materials occurring both under (as in the Longi area) and above the Calabride layers (in the latter case structurally designated the «Antisicilidi», as in the south-eastern-most zone under examination) will be attributed to the twisting course of the «Taormina line» during the migration of the Calabrian Arc towards the Ionian Basin. The proliferation of incompatible geological maps is considered to be the result of both the inadequacy of facies analysis on the varied and newly described stratigraphic columns, derived from lithoformational assemblages, and from the difficulty of discriminating between stratigraphic and structural parameters.

Diurnal change of plasma atrial natriuretic peptide (ANP) concentration was investigated in 12 patients with hypertension due to chronic renal failure (CRF) and in 12 patients with essential hypertension (EH) of comparable degree. Blood pressure (BP) monitoring was performed at 15-min intervals, while peripheral blood samples were obtained at 4-hour intervals starting from 8.00 h. The mean 24-hour plasma levels (+/- SEM) of ANP were 24.3 +/- 1.8 pmol/l in EH and 23.4 +/- 1.2 pmol/l in CRF. In EH, plasma ANP concentration was highest at 4.00 h (33.5 +/- 0.8 pmol/l) and lowest at 16.00 h (15.5 +/- 0.6 pmol/l). In CRF, no significant circadian change was present (22.2 +/- 3.1 and 20.4 +/- 3.6 pmol/l, respectively), and the nocturnal fall in BP was lost. Our data demonstrate that in CRF the loss and possible reversal of the nocturnal decline in BP is associated with the disappearance of any significant circadian variation in the circulating concentrations of ANP. These findings suggest a role for ANP in the alteration of BP variability of CRF, possibly mediated by autonomic dysfunction, and are further evidence for the existence of a relation between the circadian rhythms of ANP and BP.

12 Autologous bone marrow transplantation 168

The mechanisms underlying altered BP regulation in congestive heart failure are unknown. This study examines the possibility that differences in circadian blood pressure (BP) regulation between the normal and the failing heart correlate with changes in the circulating pattern of atrial natriuretic peptide (ANP). Twelve normotensive patients with coronary artery disease were studied over two separate 24-h periods, the first during acute exacerbation of congestive heart failure (radionuclide-determined ejection fraction at rest was less than 30%) and the second after therapy-induced functional recovery (ejection fraction was more than 40%). BP monitoring at 10-min intervals and intra-atrial blood samples for ANP assays at hourly intervals were obtained. Significant correlation between ejection fraction and the indexes of circadian BP variability (standard deviation of the 24-h pressure mean and day-night pressure difference) were found both before and after treatment. Ejection fraction was independent of the BP means (24-h, daytime and night-time). BP variability, 24-h mean and daytime mean were higher after treatment. ANP means were lower after treatment, whereas ANP variability was higher. The indexes of BP and ANP variability correlated both before and after treatment, whereas the BP and the ANP means were independent. These findings demonstrate that differences in BP regulation of CHF before and after effective treatment correlate with changes in the circulating pattern of ANP. We speculate that by modulating ANP release, the heart could be actively involved in BP regulation as part of the compensatory mechanisms aimed at protecting against circulatory overload.

The aim of this study was to assess the changes in atrial natriuretic peptide (ANP) levels before and after menopause and to test whether they depend on age or are an integral part of the hormonal changes in menopause. We measured plasma ANP, plasma renin activity (PRA), plasma aldosterone, serum estradiol-17 beta and progesterone concentrations in 103 normotensive women, either in premenopause (n = 35; mean age: 24 years), in physiological menopause (n = 34; mean age: 43 years) or surgically induced menopause (n = 34; mean age: 55 years). The last two groups were matched for duration of menopause and were comparable in their estrogen and progesterone status. PRA and plasma aldosterone concentrations decreased in postmenopausal women, whereas systolic blood pressure and ANP increased. These results were not confirmed after adjustment for age by covariance analysis. In all of the groups, plasma ANP concentrations were not significantly correlated with systolic or diastolic blood pressure, nor with plasma aldosterone, estrogen and progesterone concentrations. These correlations were not improved by correction for age. Plasma ANP concentrations were consistently correlated with age. These data suggest that the increase in plasma ANP levels found in postmenopausal women is related with age and that ANP does not play a direct role in the physiological hormonal changes of menopause.

The lack of reflex tachycardia observed after quinapril administration suggests some specific influence on autonomic function. Twelve healthy volunteers and 12 patients with essential hypertension were given a single oral 20-mg dose of quinapril and a single dose of matching placebo, in a double-blind crossover design. Blood pressure and heart rate were monitored noninvasively on a beat-to-beat basis for eight hours and indexes of autonomic function at the time of maximum effect were measured. Identical results were obtained in both normotensives and hypertensives. Neither the pressor nor the chronotropic responses to the isometric exercise and the cold pressor test were influenced by quinapril. During dynamic exercise the increments in heart rate and systolic blood pressure were unchanged by quinapril. In the orthostatic test quinapril did not significantly alter the heart rate ratio. Similarly, the heart rate response to deep breathing and apneic facial immersion showed no significant difference between quinapril and placebo, as well as the responses to the Valsalva maneuver. Our data indicate that sympathetic, parasympathetic, and baroreflex functions are unaltered by angiotensin converting enzyme inhibition with quinapril. The lack of reflex tachycardia following angiotensin-converting enzyme inhibition with quinapril remains unexplained.

The aim of this study was to assess the blood pressure profile of chronic renal failure in comparison with essential hypertension. Thirty hypertensive patients with chronic renal failure due to non-vascular nephropathies were matched by age, sex, and mean 24 h blood pressure, with 30 patients affected by uncomplicated mild-to-moderate essential hypertension. They were studied in an open hospital ward. Diet, meal times, sleep times, and activity schedules were standardized. Noninvasive, automatic, blood pressure recordings were performed for 48 h at sampling intervals of 15 min. The mean 24 h blood pressure almost coincided in the two groups. However, in essential hypertension a mean (+/- SD) nocturnal fall of systolic and diastolic blood pressure was found (12.7 +/- 3.8 and 12.9 +/- 4.8 mm Hg, respectively), while renal patients displayed an average nocturnal increase of 2.7 +/- 8.9 mm Hg and 3.7 +/- 7.8 (P less than .001). The renal patients had also higher heart rates, with a significantly blunted nocturnal fall (4.4 +/- 4.5 beats/min as compared to 9.3 +/- 3.1 beats/min of essential hypertension; P less than .001). Among the renal patients, the day-night blood pressure changes showed no significant correlation with age, creatinine clearance, hematocrit, nocturnal change in heart rate, or day or night mean blood pressure levels. These data suggest that an abnormal day-night pattern of blood pressure is present in chronic renal failure patients independently from external interfering factors. Hence, casual measurements of blood pressure confined to daytime may underestimate a hypertensive condition associated with chronic renal failure.

We demonstrated in previous works that the circadian rhythms of blood pressure (BP) and atrial natriuretic peptide (ANP) are antiphasic in normal subjects and in essential hypertension. The aim of the present study was to assess the circadian rhythms of BP and ANP in 20 patients with stable congestive heart failure (CHF), divided into two groups of 10 according to their New York Heart Association functional class. A matched control group of 10 normal volunteers was also studied. Noninvasive BP monitoring at 15-min intervals was performed for 24 h. Peripheral blood samples were also obtained at 4-h intervals starting from 08:00 h. The mean (+/- SEM) circadian mesors of ANP plasma levels were 13.4 +/- 1.7 pmol/L in the control group, 28.6 +/- 2.4 pmol/L in the group of 10 patients in class II, and 81.5 +/- 12 pmol/L in the group of 10 patients in class III-IV. In normal subjects, plasma ANP concentration was highest at 04:00 h (21.5 +/- 2.7 pmol/L) and lowest at 16:00 h (8.8 +/- 2.4 pmol/L; p less than 0.01). Both groups of patients with CHF showed no significant circadian change in the plasma levels of ANP and also a significantly blunted circadian rhythm of BP. Cosinor analysis confirmed the loss of the circadian rhythms of ANP and BP in CHF patients. Our findings support the existence of a causal relationship between the circadian rhythms of ANP and BP.

We studied the response of atrial natriuretic peptide to the hemodynamic and renin-aldosterone variations occurring in four patients who developed cardiac tamponade, either occurring in idiopathic fashion in one or secondary to metastatic involvement of the pericardium in three. Right atrial pressure, heart rate and arterial blood pressure were monitored and serial blood samples were taken before and over three hours after pericardiocentesis. During cardiac tamponade, normal levels of atrial natriuretic peptide (mean ± SEM: 54 ± 7.4 pg/ml) were observed in the plasma despite increased right atrial pressure (23 ± 3.8 cm H2O) and heart rates (98 ± 4.4). Removal of pericardial fluid (540 to 1160 ml) was associated at first with a 200% increase in plasma concentrations of atrial natriuretic peptide (108 ± 8.8 pg/ml; P < 0.001), then with a gradual decline toward normal levels, simultaneous with the normalization of right atrial pressure and heart rate. Activity of renin and concentrations of aldosterone in the plasma were increased during tamponade and returned gradually to normal after pericardiocentesis (3.8 ± 0.9 to 1.2 ± 0.3 ng/ml/h and 20 ± 4.2 to 9 ± 3.2 ng/dl, respectively; P < 0.01). These data confirm that atrial strain, not intracavitary pressure in itself nor heart rate, is the main determinant of the acute release of atrial natriuretic peptide, which is associated with a suppressing effect on the renin-aldosterone system. In addition, our data indicate that secretion of atrial natriuretic peptide during cardiac tamponade is not stimulated by secondary hyperal-dosteronism.