Fault tectonics of the Tuscan Nappe in the eastern sector of the Apuan Alps (Italy)

We present the geological-structural map of the Tuscan Nappe exposed on the eastern border of the Apuan Alps metamorphic dome (Tuscany, Italy). The 1:6,500 scaled Main Map covers an area of about 10 km(2). It contains the first detailed overview of the fault tectonics affecting the Tuscan Nappe during the exhumation and uplift of the Tuscan Metamorphic Units. We documented a polyphase fault tectonics that initially produced low-angle extensional faults and later high-angle faults. The latter started within a transtensional tectonic regime that produced left-lateral strike-slip faults. Lately a pure extensional tensor, indicating a switch of the maximum compression sigma 1 axis from sub-horizontal to sub-vertical, produced faults with a dominant dip-slip component. In our reconstruction the lateral thickness variations documented in several formations of the Tuscan Nappe is mainly controlled by tectonics and not by stratigraphy, as previously suggested

Syn-exhumation coupling of oceanic and continental units along the western edge of the alpine corsica: A review

The Alpine Corsica represents a segment of the Alpine collisional belt. In its western edge, it is characterized by the close association of continental units deformed under high-pressure metamorphic conditions (Lower Units) and oceanic units showing a metamorphism ranging from high-pressure (Schistes Lus-trés Complex) to very low-grade conditions (Upper Units). This paper provides a complete review of the relationships between the continental and oceanic units in selected five areas where the stratigraphic features, deformation history, metamorphic P-T path and tectonic setting are available for each unit. The collected data indicate that the oceanic units occur not only at the top of the continental ones, as generally proposed in the literature, but also intercalated within them. Such relationships were achieved at shallow structural level during the late stage of exhumation, when the continental units were tectonically coupled with the oceanic units which were dragged as slices from the orogenic wedge. The coupling probably occurred immediately before the transition from syn-to post-orogenic geodynamic regime that affected the whole Alpine-Apennine collisional system in the early Oligocene. After the coupling, the stack of oceanic and continental units experienced a further exhumation-related deformation before their final exposure at the surface

Evidences for a Late Cretaceous continental arc in the Central Pontides: new insights on alternative geodynamic reconstructions for the Neotethys in Northern Turkey

The Intra-Pontide Suture Zone (IPSZ) is the less known one among the suture zones present in Turkey. The IPSZ is well exposed along the Daday-Arac-Kursunlu and Tosya – Emirköy geotraverses where several tectonic units can be recognized. Most of these units are characterized by the occurrence of basic rocks reflecting distinct tectonic origins and geochemical signatures. The study of the basic rocks emerges as an important tool for the geodynamic reconstruction as it can reveal the occurrence of of different types of oceanic basins, the development of a magmatic arc or the presence of rifting-related magmatism. The study of the geotraverses indicates that the imbricate stack of the IPSZ consists of four distinct tectonic units whose successions bear basic rocks: the Aylı Dağ ophiolite Unit, the Arkot Dağ Mèlange and two metamorphic units, referred to as Daday and Devrekani Units. This imbricate stack is probably the result of several episodes of out-of-sequence thrusts that affected the whole IPSZ. The Aylı Dağ Unit includes an about 5 km-thick ophiolite sequence topped by the middle Bathonian to early Callovian radiolarian cherts. In addition, a metamorphic sole is present at the base of the serpentinized peridotites. The geochemical evaluation of pillow-basalts and dykes highlights subduction-related characteristics, similar to IAT- and BABB-type lavas generated above intra-oceanic subduction systems. The Arkot Dağ Mèlange consists of an assemblage of slide-blocks, with different size and lithology, enclosed in a Late Santonian sedimentary matrix. The slide-blocks also include ophiolitic lithologies, mainly represented by basalts, but gabbros and peridotites are also found. The slide-blocks of basalts display affinites to IAT- and BABB-type magmas, signifying the involvement of subduction component, whereas no MORB-like basalt have been found. The Daday unit is characterized by metasedimentary and metabasic rocks deformed under blueschist to subgreenschist metamorphic facies conditions. The metasedimentary rocks include mica-bearing schists, fine-grained marbles and black quartzites. The metabasic lithologies, on the other hand, comprise actinolite-bearing schists and Naamphibole- bearing varieties possibly derived from basaltic and gabbroic protoliths. The metabasic rocks have a wide range of chemical compositions, displaying N-MORB-, E-MORB-, OIB- BABB- and IAT-type signatures. The Devrekani Unit is represented by an assemblage of amphibolites, marbles and micaschists showing a metamorphic climax developed under upper amphibolite facies in the Late Jurassic time. The amphibolites display EMORB-, OIB- BABB- and IAT-type signatures. The geochemical signature of the studied basic rocks provide the evidence that all the basic rocks from the tectonic units of IPSZ are derived by a supra-subduction zone. This finding can provide new nsights for the recostruction of the sgeodynamic history of the Intra-Pontide domain

Burial and exhumation history of the Daday Unit (Central Pontides, Turkey): implications for the closure of the Intra-Pontide oceanic basin

In northern Turkey, the Intra-Pontide suture zone represents one of the first-order tectonic structures located between the Istanbul-Zonguldak and the Sakarya continental terranes. It consists of an east-west trending assemblage of deformed and variably metamorphosed tectonic units, including sedimentary rocks and ophiolites derived from a NeoTethyan oceanic basin, known as Intra-Pontide oceanic basin. One of these units is represented by the Daday Unit that consists of an assemblage of block-in-matrix derived from a supra-subduction oceanic crust and related deep-sea sedimentary cover of Middle Jurassic age. This setting has been acquired during the Late Jurassic by underplating at 26-38 km of depth associated with blueschist facies metamorphism (D1 phase). The following D2, D3 and D4 phases developed in a time span running from Albian to late Paleocene during the exhumation of the Daday Unit from 26-38 km to uppermost structural levels. The high geothermal gradient detected during the development of the D2 phase seems to be consistent with the exhumation of the Daday Units during a continent-arc collisional setting. The tectonic structures of the Intra-Pontide suture zone, resulting from the previously described tectonic history, are unconformably sealed by the late Paleocene - Eocene deposits. This tectonic setting was intensely reworked by the activity of the North Anatolian Fault Zone, producing the present-day geometrical relationships of the Intra-Pontide suture zone of central Pontides

Subpopulations of anti-β2glycoprotein I antibodies with different pathogenic potential: fine specificity against the domains of β2glycoprotein I

Objective: Anti-β2glycoprotein I antibodies (a-β2GPI) are a laboratory criterion for the antiphospholipid syndrome (APS) and were demonstrated to be involved in the pathogenesis of APS. However, they can also be detected in asymptomatic subjects. It has been suggested that a-β2GPI against Domain1 (D1) associate with thrombosis, while those recognizing Domain4/5 (D4/5) have been identified in non-thrombotic conditions. We evaluate the specificity of a- β2GPI in different clinical situations. Methods: We studied 39 one-year-old healthy children born to mothers with systemic autoimmune diseases (SAD) (15 (38.4%) were born to mothers who were a-β2GPI positive), 33 children with atopic dermatitis (AD) and 55 patients with APS (50 adults and 5 paediatrics). All subjects were IgG a-β2GPI positive. IgG a-β2GPI were performed by homemade ELISA, while IgG a-β2GPI D1 and D4/5 were tested on research ELISAs containing recombinant β2GPI domains antigens. Results: One-year-old children and AD children displayed preferential reactivity for D4/5; patients with APS recognized preferentially D1. We also found a good correlation between a-β2GPI and D4/5 in one-year-old (r=0.853) and AD children (r=0.879) and between a-β2GPI and D1 in the APS group (r=0.575). No thrombotic events were recorded in both groups of children. Conclusions: A-β2GPI found in non-thrombotic conditions (healthy children born to mothers with SAD and AD children) mostly recognize D4/5, in contrast to the prevalent specificity for D1 in the APS group. The different specificity could at least partially explain the "innocent" profile of a-β2GPI in children

Lung ultrasound: a new tool for the cardiologist

For many years the lung has been considered off-limits for ultrasound. However, it has been recently shown that lung ultrasound (LUS) may represent a useful tool for the evaluation of many pulmonary conditions in cardiovascular disease. The main application of LUS for the cardiologist is the assessment of B-lines. B-lines are reverberation artifacts, originating from water-thickened pulmonary interlobular septa. Multiple B-lines are present in pulmonary congestion, and may help in the detection, semiquantification and monitoring of extravascular lung water, in the differential diagnosis of dyspnea, and in the prognostic stratification of chronic heart failure and acute coronary syndromes

Macrophage activation syndrome in adult systemic lupus erythematosus: report of seven adult cases from a single Italian rheumatology center.

The aim was to describe the macrophage activation syndrome (MAS), a life-threatening syndrome characterized by excessive immune activation that can be triggered by conditions affecting immune homeostasis, in a cohort of adult Italian patients with systemic lupus erythematosus (SLE). This was a monocentric retrospective evaluation. The utility of the H-score, developed to estimate the individual risk of having reactive MAS in adult patients, was assessed. Among 511 patients with SLE, 7 cases (1.4%) of MAS (all females) were identified and their medical records reviewed. In all cases, MAS was simultaneous to the onset of SLE. All patients had fever, lymphadenopathy, hematological involvement, and high titer of anti-dsDNA antibodies. Workup for infections and malignancies was negative. In all cases, the H-score was higher than the cut-off suggested for the classification of reactive MAS. All cases required hospital admission, and 2 patients were admitted to the intensive care unit. Most patients were treated successfully with high doses of corticosteroids and with immunosuppressive drugs, whereas the full therapeutic regimen developed for primary hemophagocytic lymphohistiocytosis HLH was used only in one case. No death from MAS was observed. MAS is a rare and severe disorder that complicated the onset of SLE in our cohort. The H-score may be useful in the classification of these patients

[Ultrasound lung comets: new echographic sign of lung interstitial fibrosis in systemic sclerosis].

Objective: Interstitial lung disease (ILD) and pulmonary arterial hypertension (PAH) are common complications of systemic sclerosis (SSc). Echocardiography evaluates PAH, and chest sonography detects even mild ILC as ultrasound lung comets (ULC), i.e. multiple comet-tails fanning out from the lung surface and originating from subpleural interlobular septa thickened by fibrosis. Aim: to assess ILaD and PAH by integrated cardiac and chest ultrasound in SSc. Methods: We enrolled 30 consecutive SSc patients (age= 54±13 years, 23 females) in the Rheumatology Clinic of Pisa University. In all, we assessed systolic pulmonary arterial pressure (SPAP), from maximal velocity of tricuspid regurgitation flow, and ULC score with chest sonography (summing the number of ULC from each scanning space of anterior and posterior right and left chest, from second to fifth intercostal space). All patients underwent plasma assay for anti-topoisomerase antibodies (anti-Scl70), and antiicentromere associated with development of pulmonary involvement. Twenty-eight patients also underwent high resolution computed tomography, HRCT (from 0= no fibrosis to 3= honey combing). Results: ULC number - but not SPAP - was correlated to HRCT fibrosis and presence Scl-70 antibodies. ULC number was similar in localized or diffuse forms (16±20 vs 21±19, p=ns) and was unrelated to SPAP (r=0.216, p=ns). Conclusions: Chest sonography assessment and ULC allow a complete, simple, radiation-free characterization of interstitial lung involvement in SSc - all in one setting and with the same instrument, same transducer and the same sonographer. In particular, ULC number is associated with HRCT evidence of lung fibrosis and presence of Scl-70 antibodies