Fluid inclusion study of the Boccassuolo VMS-related stockwork deposit (Northern-Apennine ophiolites, Italy)

Several Cyprus-type volcanogenic massive sulphide (VMS) deposits are found in the Jurassic ophiolitic series of the Northern Apennines. Stratabound, stratiform and stockwork deposits were formed in the western limb of the Neotethys (Ligurian Ocean) and are found today in basalt, gabbro and serpentinised peridotite host rocks. The studied stockwork deposit at Boccassuolo is found in basalt and basalt breccia. Detailed petrography, fluid inclusion study, Raman spectroscopy analyses and chlorite thermometry calculations were used to determine the P, T, X conditions of the fluid circulation system. The veins contain three quartz generations, calcite, chlorite, epidote and sericite as gangue minerals and pyrite, chalcopyrite, sphalerite, pyrrhotite and galena as ore minerals. Based on the fluid inclusion study, the earlier defined three vein types (1., 2. and 3.) precipitated from the same type of evolving fluid, though at slightly different stratigraphical positions. The determined ranges of temperature (370 60°C), salinity (6.2 11.4 NaCl equiv. wt%), pressure (30-44 MPa) ranges and methane content (average 0.28 mol/kg) suggest an evolved seawater origin for the hydrothermal fluid, modified by fluid-rock interaction and possibly by mixing of magmatic volatile. The fluid characteristics and the mineralogical observations have proven a slightly distal position in relation to the centre of the fluid flow for all studied locations, but less and more distal blocks were also recognised. The temporal evolution of the system developed into a low temperature event, occurring after the main mineral stage, but still participating to the same process as a whole.</p

Pidotimod: The state of art

Despite the use of antibiotics and vaccines, the frequency of respiratory tract infections is still high and these infections interest a wide range of patients, from children to aged people, including in particular these extreme categories because of the deficiency of their immune system, due to immaturity in the former case and to "immunosenescence" in the latter. For that reason immunostimulant drugs are getting more important to prevent and to attenuate infections. Pidotimod (3-L-pyroglutamyl-L-thiazolidine-4carboxylic acid) is a synthetic dipeptide with immunomodulatory properties. We reviewed studies conducted on different categories of patients, with particular attention on children and senile patients suffering from recurrent respiratory tract infections, associated, or not, with asthma or COPD. The outcomes considered are both clinical and laboratory parameters. The common end-point of these studies is that Pidotimod has an immunomodulatory activity which is able both to improve the clinical conditions of patients and to enhance and stimulate their immunity cells (lymphocytes but not only) functions acting on adaptive and innate immunity. Pidotimod is also able to increase the concentration of salivary IgA directed against bacteria; furthermore, it can modulate airway epithelial cells functions up-regulating the expression of toll-like receptors and acting on adhesion molecules. According to studies conducted on patients with atopic asthma, it seems that Pidotimod could affect T-lymphocytes balance with a possible addictional anti-allergic activity. Furthermore, it has been demonstrated an improvement of FEV1 and PEF in asthmatic patients treated with Pidotimod. Main clinical outcomes are the reduction of the number of infectious episodes, lesser severity of signs and symptoms and, consequently, a reduction in use of antibiotics and symptomatic drugs, less working and school days lost, less mortality and morbidity. The studies considered give positive results, confirming Pidotimod's efficacy. Furthermore, many studies show a good safety profile of the drug, without recording serious adverse events and mutagenic potential, and a very low incidence of side effects. Pidotimod is also a more safe solution in patients subjected to vaccination, if compared to lyophilized polibacterial, which can't be administered for thirty days before vaccination

Arsenotučekite, Ni 18 Sb 3 AsS 16 , a new mineral from the Tsangli chromitites, Othrys ophiolite, Greece

AbstractArsenotučekite, Ni18Sb3AsS16, is a new mineral discovered in the abandoned chromium mine of Tsangli, located in the eastern portion of the Othrys ophiolite complex, central Greece. Tsangli is one of the largest chromite deposit at which chromite was mined since 1870. The Tsangli chromitite occurs as lenticular and irregular bodies. The studied chromitites are hosted in a strongly serpentinized mantle peridotite. Arsenotučekite forms anhedral to subhedral grains that vary in size between 5 μm up to 100 μm, and occurs as single phase grains or is associated with pentlandite, breithauptite, gersdorffite and chlorite. It is brittle and has a metallic luster. In plane-polarized light, it is creamy-yellow, the bireflectance is barely perceptible and the pleochroism is weak. In crossed polarized reflected light, the anisotropic rotation tints vary from pale blue to brown. Internal reflections were not observed. Reflectance values of arsenotučekite in air (Ro, Re′ in %) are: 41.8–46.4 at 470 nm, 47.2–50.6 at 546 nm, 49.4–52.3 at 589 nm, and 51.3–53.2 at 650 nm. The empirical formula of arsenotučekite, based on 38 atoms per formula unit, and according to the structural results, is (Ni16.19Co1.01Fe0.83)Σ18.03Sb3(As0.67Sb0.32)Σ0.99S15.98. The mass density is 6.477 g·cm−3. The simplified chemical formula is (Ni,Co,Fe)18Sb3(As,Sb)S16. The mineral is tetragonal and belongs to space group I4/mmm, with a = 9.7856(3) Å, c = 10.7582(6) Å, V = 1030.2(6) Å3 and Z = 2. The structure is layered (stacking along the c-axis) and is dominated by three different Ni-coordination polyhedral, one octahedral and two cubic. The arsenotučekite structure can be considered as a superstructure of tučekite resulting from the ordering of Sb and As. The name of the new mineral species indicates the As-dominant of tučekite. Arsenotučekite occurs as rims partly replacing pentlandite and irregularly developed grains. Furthermore, it is locally associated with chlorite. These observations suggest that it was likely precipitated at relatively low temperatures during: 1) the late hydrothermal stages of the ore-forming process by reaction of Sb- and As-bearing solutions with magmatic sulfides such as pentlandite, or 2) during the serpentinization of the host peridotite. The mineral and its name have been approved by the Commission of New Minerals, Nomenclature, and Classification of the International Mineralogical Association (number 2019–135)

Metronomic capecitabine vs. best supportive care in Child-Pugh B hepatocellular carcinoma: A proof of concept

There is a relative lack of evidence about systemic treatments in patients with hepatocellular carcinoma (HCC) and moderate liver dysfunction (Child-Pugh B). In this multicenter study we retrospectively analyzed data from Child-Pugh B-HCC patients na\uefve to systemic therapies, treated with MC or best supportive care (BSC). To reduce the risk of selection bias, an inverse probability of treatment weighting approach was adopted. Propensity score was generated including: extrahepatic spread; macrovascular invasion; performance status, alphafetoprotein &gt; 400 ng/ml, Child- Pugh score [B7 vs. B8-9]. We identified 35 MC-treated patients and 70 controls. Median overall survival was 7.5 [95% CI: 3.733-11.267]in MC-patients and 5.1 months [95% CI: 4.098-6.102] in the BSC group (p = 0.013). In patients treated with MC, median progression-free survival was 4.5 months (95% CI: 2.5-6.5). The univariate unweighted Cox regression showed a 42% reduction in death risk for patients on MC (95%CI: 0.370-0.906; p = 0.017). After weighting for potential confounders, death risk remained essentially unaltered. In the MC group, 12 patients (34.3%) experienced at least one adverse event, the most common of which were: fatigue (17.1%), hand-foot syndrome (8.5%), thrombocytopenia (8.5%), and neutropenia (5.7%). MC seems a safe option for Child-Pugh B-HCC patients. Its potential antitumour activity warrants prospective evaluations

Age, geochemistry and petrogenesis of the ultramafic pipes in the Ivrea Zone, NW Italy

Pipe-like ultramafic bodies, hosting Ni-Cu-PGE sulphide deposits, intrude the Main Gabble and the roof metasediments of the Ivrea Zone, NW Italy. These bodies were emplaced at 287 +/- 3 Ma and represent the last mantle-derived melts associated with an underplating event that largely drove the crustal evolution of this area during the late Carboniferous (similar to 300-290 Ma). nle Pipes are composed of volatile-rich ultramafic locks and gabbros with an alkaline signature simultaneously enriched in both incompatible and the most compatible elements but depleted in elements of intermediate compatibility. The isotope composition of these pipe rocks is E-290Ma(Nd) similar to3.7 to -1.9 and E-290Ma(Sr) similar to0.8-26. In a E-290Ma((Nd)) vs E290(Ma)(Sr) diagram they define a linear array between the unmetasomatized and metasomatized peridotites of Finero, but distinctlj oblique with respect to the trend defined by Balmuccia Peidotites. irhe delta S-34 ranges from 0.0 to + 0.9%(0) and is indicative of a mantle source. We suggest that the pipes represent infiltration of melts derived from a depleted mantle protolith flushed with alkaline metasomatic fluids, probably of juvenile mantle origin, which underwent partial melting as a consequence of the depression of the solidus owing to the increased activity of water and other volatiles. The similarity in age, trace-element, and isotopic signatures indicates that the Pipes were probably produced in the course of the same metasomatic event that affected the Finero ultramafic body. The overall geochemical characteristics of the pipes ale more consistent with magmatism related to a mantle plume than with a subduction setting

High and Low Temperature Gold Mineralizations in the Fe–Cu–Zn Sulfide Deposits of Corchia Ophiolite, Northern Italian Apennine

mineral

Exotic accessory minerals in layered chromities of the Campo Formoso complex (Brazil)

The Campo Formoso stratiform intrusive complex, in Bahia State, Brazil, considered to be of Paleoproterozoic age, consists of a tabular body of ultramafic rocks about 40 km long and 100-1100 m wide. Thick horizons of chromitite are exploited and the deposits are the richest in Brazil. The complex was intruded by the Campo Formoso calc-alkaline batholith, emplaced by the result of the Transamazonian collision-related orogeny. The peridotite was firstly thoroughly serpentinized, then affected by a renewed cycle of hydrothermal alteration as the batholith cooled, leading in the roof zone to emerald mineralization around roof pendants. An even later influx of fluid led to the formation of talc, silica and carbonates, such that the ultramafic rocks were locally converted to listwanite. The chromitite sequences are highly unusual in containing rather exotic minerals, such as monazite-(La), monazite-(Ce), apatite, galena, bismuthinite, antimony, and three unknown minerals of stoichiometry PbSb2, Pb Sb and PbSb4, all associated with the clinochlore. The latter phases may have formed during hydrothermal activity in the system Pb-Sb. The presence of these exotic minerals in chromitite, which makes this occurrence unique in the world, strongly support the hypothesis that the La, Ce, P, Pb, Bi and Sb were metasomatically added to the Campo Formoso chromitite horizons by hydrothermal fluids emanating from the nearby Campo Formoso calc-alkaline batholith as it cooled

Zirconolite and Zr-Th-U minerals in chromitites of the Finero complex, Western Alps, Italy: evidence for carbonatite-type metasomatism in a subcontinental mantle plume

Zirconolite (CaZrTi2O7) associated with baddeleyite (ZrO2), thorianite (ThO2), uraninite (UO2), thorite or huttonite (ThSiO4) and zircon (ZrSiO4) has been discovered in chromitites of the Finero mantle-derived massif, in the Western Alps of Italy. The exotic minerals do not occur in late veins or fractures; they are part of the accessory assemblage (phlogopite, amphibole, apatite, ilmenite, geikielite, rutile, molybdenite, and Mg-Ca carbonates) formed as a result of metasomatism of the Finero mantle. Textural relations of zirconolite and the Zr-Th-U minerals indicate crystallization with the chromite - olivine - orthopyroxene assemblage between 800degrees and similar to600degreesC, at a given pressure of 1.0 GPa. Zirconolite is an indicator of silica-undersaturated conditions. Its composition, characterized by the prevalence of Th and U over Nb and Ta, is similar to that of zirconolite from some carbonatite complexes. The close association with Zr-Th-U minerals, and with the carbonatite-compatible elements Y, Hf, Pb, and LREE, is symptomatic of the carbonatitic character of metasomatism at Finero. The formation of a carbonatite-type liquid and related hydrous fluid is commonly related to the emplacement of mantle plumes in continental rift systems worldwide. This supports the inference that the metasomatism of the Finero mantle was a result of mantle diapirism at the base of the continental crust induced by extensional tectonics in pre-Hercynian times