Potentially toxic elements distribution in the serpentinized and deformed ultramafic rocks from the Voltri Massif (NW, Italy)

The aim of the work is to assess the role of local-scale lithological, textural, and structural factors in the distribution of potentially toxic elements (PTEs) in different ultramafic rocks from the high-pressure ophiolitic Voltri Massif (Central Liguria, NW Italy). The results evidenced that Cr (up to 4183 ppm), Ni (up to 3900 ppm), and Co (up to 334 ppm) are invariably the PTEs with the highest concentrations; in addition, V, Cu, and Zn are systematically found in non-negligible amounts. Spinel-group minerals (chromium spinel, ferrian chromite, chromium magnetite, and magnetite) are by far the main potential source of the PTEs. Nevertheless, several PTEs are also present within serpentines, olivines, pyroxenes, chlorites, as well as within accessory phases (e.g., ilmenite and Ni-sulphides) and within authigenic minerals formed in the early stages of rock weathering (cryptocrystalline to amorphous Fe-oxides and -oxyhydroxides). The result obtained allowed to evidence that the main factors controlling the PTEs distribution within the rocks resulted to be the serpentinization degree and the deformation style and intensity which, in turn, strictly control the mineral assemblages and the mineral chemistry

Platelet derived growth factor B gene expression in the Xenopus laevis developing central nervous system

Platelet-derived growth factor B (PDGF-B) belongs to the mitogen and growth factor family and like the other members it has many roles in cell differentiation, proliferation and migration during development, adult life and in pathological conditions. Among them it has been observed that aberrant PDGF signalling is frequently linked to glioma development and progression, and Pdgf-b over-expression in mouse neural progenitors leads to the formation of gliomas. Despite this evidence, the mechanisms underlying PDGF-B driven tumorigenesis and its role during brain development are not fully understood. In order to contribute to clarifying possible new roles of pdgf-b signalling, we present here the embryonic gene expression pattern of pdgf-b, so far unknown in early vertebrate development. By using Xenopus laevis as a model system we performed qRT-PCR and whole mount in situ hybridization. Pdgf-b mRNA is expressed in discrete regions of the developing central nervous system, in the cranial nerve placodes and in the notochord. We also compared the gene expression of pdgf-b with that of its receptor pdgfr-a suggesting so far unsuspected roles for this signalling pathway during the development of specific embryonic structures

Altered brain morphometry in carpal tunnel syndrome is associated with median nerve pathology☆☆☆

Objective: Carpal tunnel syndrome (CTS) is a common median nerve entrapment neuropathy characterized by pain, paresthesias, diminished peripheral nerve conduction velocity (NCV) and maladaptive functional brain neuroplasticity. We evaluated structural reorganization in brain gray matter (GM) and white matter (WM) and whether such plasticity is linked to altered median nerve function in CTS. Methods: We performed NCV testing, T1-weighted structural MRI, and diffusion tensor imaging (DTI) in 28 CTS and 28 age-matched healthy controls (HC). Voxel-based morphometry (VBM) contrasted regional GM volume for CTS versus HC. Significant clusters were correlated with clinical metrics and served as seeds to define associated WM tracts using DTI data and probabilistic tractography. Within these WM tracts, fractional anisotropy (FA), axial (AD) and radial (RD) diffusivity were evaluated for group differences and correlations with clinical metrics. Results: For CTS subjects, GM volume was significantly reduced in contralesional S1 (hand-area), pulvinar and frontal pole. GM volume in contralesional S1 correlated with median NCV. NCV was also correlated with RD and was negatively correlated with FA within U-fiber cortico-cortical association tracts identified from the contralesional S1 VBM seed. Conclusions: Our study identified clear morphometric changes in the CTS brain. This central morphometric change is likely secondary to peripheral nerve pathology and altered somatosensory afference. Enhanced axonal coherence and myelination within cortico-cortical tracts connecting primary somatosensory and motor areas may accompany peripheral nerve deafferentation. As structural plasticity was correlated with NCV and not symptomatology, the former may be a better determinant of appropriate clinical intervention for CTS, including surgery

Functional deficits in carpal tunnel syndrome reflect reorganization of primary somatosensory cortex

Carpal tunnel syndrome, a median nerve entrapment neuropathy, is characterized by sensorimotor deficits. Recent reports have shown that this syndrome is also characterized by functional and structural neuroplasticity in the primary somatosensory cortex of the brain. However, the linkage between this neuroplasticity and the functional deficits in carpal tunnel syndrome is unknown. Sixty-three subjects with carpal tunnel syndrome aged 20–60 years and 28 age- and sex-matched healthy control subjects were evaluated with event-related functional magnetic resonance imaging at 3 T while vibrotactile stimulation was delivered to median nerve innervated (second and third) and ulnar nerve innervated (fifth) digits. For each subject, the interdigit cortical separation distance for each digit’s contralateral primary somatosensory cortex representation was assessed. We also evaluated fine motor skill performance using a previously validated psychomotor performance test (maximum voluntary contraction and visuomotor pinch/release testing) and tactile discrimination capacity using a four-finger forced choice response test. These biobehavioural and clinical metrics were evaluated and correlated with the second/third interdigit cortical separation distance. Compared with healthy control subjects, subjects with carpal tunnel syndrome demonstrated reduced second/third interdigit cortical separation distance (P < 0.05) in contralateral primary somatosensory cortex, corroborating our previous preliminary multi-modal neuroimaging findings. For psychomotor performance testing, subjects with carpal tunnel syndrome demonstrated reduced maximum voluntary contraction pinch strength (P < 0.01) and a reduced number of pinch/release cycles per second (P < 0.05). Additionally, for four-finger forced-choice testing, subjects with carpal tunnel syndrome demonstrated greater response time (P < 0.05), and reduced sensory discrimination accuracy (P < 0.001) for median nerve, but not ulnar nerve, innervated digits. Moreover, the second/third interdigit cortical separation distance was negatively correlated with paraesthesia severity (r = −0.31, P < 0.05), and number of pinch/release cycles (r = −0.31, P < 0.05), and positively correlated with the second and third digit sensory discrimination accuracy (r = 0.50, P < 0.05). Therefore, reduced second/third interdigit cortical separation distance in contralateral primary somatosensory cortex was associated with worse symptomatology (particularly paraesthesia), reduced fine motor skill performance, and worse sensory discrimination accuracy for median nerve innervated digits. In conclusion, primary somatosensory cortex neuroplasticity for median nerve innervated digits in carpal tunnel syndrome is indeed maladaptive and underlies the functional deficits seen in these patients

Outcomes of pregnancies after kidney transplantation: lessons learned from CKD. A comparison of transplanted, nontransplanted chronic kidney disease patients and low-risk pregnancies: a multicenter nationwide analysis.

BACKGROUND: Kidney transplantation (KT) may restore fertility in CKD. The reasons why materno-foetal outcomes are still inferior to the overall population are only partially known. Comparison with the CKD population may offer some useful insights for management and counselling.Aim of this study was to analyse the outcomes of pregnancy after KT, compared with a large population of non-transplanted CKD patients and with low-risk control pregnancies, observed in Italy the new millennium. METHODS: We selected 121 live-born singletons after KT (Italian study group of kidney in pregnancy, national coverage about 75%), 610 live-born singletons in CKD and 1418 low-risk controls recruited in 2 large Italian Units, in the same period (2000-2014). The following outcomes were considered: maternal and foetal death; malformations; preterm delivery; small for gestational age baby (SGA); need for the neonatal intensive care unit (NICU); doubling of serum creatinine or increase in CKD stage. Data were analysed according to kidney diseases, renal function (staging according to CKD-EPI), hypertension, maternal age, partity, ethnicity. RESULTS: Materno-foetal outcomes are less favourable in CKD and KT as compared with the low-risk population. CKD stage and hypertension are important determinants of results. KT patients with e-GFR >90 have worse outcomes compared with CKD stage 1 patients; the differences level off when only CKD patients affected by glomerulonephritis or systemic diseases ('progressive CKD') are compared with KT. In the multivariate analysis, risk for preterm and early-preterm delivery was linked to CKD stage (2-5 versus 1: RR 3.42 and 3.78) and hypertension (RR 3.68 and 3.16) while no difference was associated with being a KT or a CKD patient. CONCLUSIONS: The materno-foetal outcomes in patients with kidney transplantation are comparable with those of nontransplanted CKD patients with similar levels of kidney function impairment and progressive and/or immunologic kidney diseas

Geology of the Pontinvrea area (Ligurian Alps, Italy): structural setting of the contact between Montenotte and Voltri units

This geological map at the 1:10,000 scale shows the structural setting of two poly-deformed metaophiolite units, with different metamorphic peak conditions, i.e. the blueschist facies Montenotte Unit and the eclogite facies Voltri Unit, in a selected area of 8.2 km2 within the Ligurian Alps (northern Italy). This study focuses on the tectonic contact between the two tectono-metamorphic units and on their relationships with the Oligocene sediments of the Tertiary Piedmont Basin. The map is a composite report of our field and laboratory study of structures and metamorphism, that explains our interpretation of the tectonic history of the study area. It shows that the two units were coupled during their exhumation path, along a blueschist facies mylonitic contact. This contact has been later involved in thrust faults that caused the superposition of the metamorphic basement on top of the Oligocene sediments