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To establish whether misoprostol (a synthetic prostanoid) is effective in improving intestinal metaplasia of dyspeptic patients.Of the 206 dyspeptic patients without Helicobacter pylori, 18 (7.1%) had histological evidence of intestinal metaplasia (2 presented mild metaplasia, 9 moderate and 7 severe). They were treated with misoprostol 200 mg twice daily for six months and, after stopping the treatment, they all underwent endoscopic control.There was a statistical significant improvement of intestinal metaplasia (p0.001) and of the activity of antral gastritis (p = 0.03). There were no significant changes in antral and body specimens during follow-up.Though the small number of the patients and the lack of control group, our results suggest that misoprostol allows regression and/or improvement of histological IM (p0.001). It has proved to be effective in prevention of both gastric and duodenal ulcers induced by NSAID therapy, probably related largely to replacement of endogenous prostaglandins inhibited by the use of NSAID and it may also exerts its protective effects through inhibition of gastric acid secretion. Moreover, misoprostol showed to increase the rate of gastric blood flow, inducing a mucosal protective effect against the factors damaging gastric mucosa. It has been also documented that misoprostol regulates inflammatory cytokines and prolonged the survival of transplants, reflecting both its immunosuppressive and anti-inflammatory effect. In conclusion, since intestinal metaplasia increases the risk of gastric cancer, the use of misoprostol, in this pathology, would be of some interest.

The incidence and mortality rate of acute appendicitis for the years 1955 and 1987 were calculated on the basis of data used by ISTAT. In 1955 the incidence was 5.7 per 1000 whereas in 1987 this had fallen to 3.7 per 1000. In both years examined there was a prevalence of females (in 1987 females accounted for 4.3 per 1000 in comparison to 3 per 1000 recorded for for males). In 1987 the lowest incidence was recorded in the over 60 years olds, whereas the highest incidence was in males between 1 and 14 years old (7.57 per 1000) and females between 15 and 24 years old (12.17 per 1000). Mortality diminished from 0.42% in 1955 to 0.05% in 1987. The highest rate of mortality was recorded in those patients over 60 years old (1.5%).

New data on the potential impact of environmental parameters and the mineralogical nature of the substrate on the hatching success of the loggerhead sea turtle Caretta caretta on a volcanic beach on Linosa Island in the central Mediterranean Sea are reported. During 2 years of investigation (2018-19), five nests were observed. The temperature and moisture of the nests were determined along with the grain size and mineralogical nature of the substrate. The temperature values of the nests recorded at depths of 5 and 35 cm showed an average temperature incubation of 32.2°C ± 1.4°C and 32.8°C ± 1.6°C, respectively, with peaks close to 37°C. The sedimentological analysis carried out on two cores revealed the prevalence of large sandy particle and sediment moisture of about 35% in the deeper layers. A total of 214 laid eggs were recorded in 2018 with only 44 emerged turtles, whereas 45 turtles emerged from 199 laid eggs in 2019. Both years showed a low hatching success (25%-30%) and a high frequency of anomalies (>60%), which were present in individuals as nonmodal scutes or bifid limbs. Results suggest that environmental parameters such as temperature, sand moisture, and the geological nature of the substrate seem to play an important role in the reproductive success of this species. Some aspects for improving the nesting site and egg development conditions are also discussed.

A multi-scale analysis of sedimentary carbonate facies and post-sedimentary diagenetic features of the Calcare di Base Formation, the precursor to evaporites in Upper Messinian successions of Northern Calabria and Central Sicily, has revealed their microbial bio-mediated origin. Massive to laminated microbial boundstones represent the most common sedimentary facies forming flat to low relief cm to m scale stromatolitic and thrombolitic bodies. The fabric of the micrite varies from peloidal to aphanitic, and almost always preserves filamentous bacteria which characterized the original microbial mat. The mat was dominated by sulphur-oxidizing bacteria belonging to the Thiotrichaceae, but there is evidence for a more complex community with sulphate- and/or nitrate-reducing bacteria, all being responsible for the mediation of the carbonate precipitation. Microbial boundstones are rich in pseudomorphs of Ca-sulphate and halite, which formed during the deposition of the microbial carbonate. Layers of primary gypsum are interbedded locally with carbonates suggesting the presence of restricted marine conditions. The stable O and C isotopic composition of the carbonates, that vary from dolomite to aragonite and calcite, suggests a complex interplay between arid to humid climatic changes, expressed cyclic interbedding of the carbonate with marl-marlstone. Later diagenetic events mainly consist of phreatic meteoric recrystallization and cementation. Although considered as diachronous, the microbial carbonates can be mapped out over a distance of more than 500 km across southern Italy; this indicates near-constant environmental conditions upon the central Mediterranean shelf at the beginning of the salinity crisis. Deposition of the extensive subaqueous microbial deposit that largely comprises the Calcare di Base is envisaged to have taken place across a shallow to moderate depth platform with local slopes into deeper water areas, where some resedimentation occurred.

Planktonic foraminiferal biostratigraphy and isotope stratigraphy analyses of Turonian-Maastrichtian deposits have been carried out in the western part of the Kopet-Dagh Basin. The identification of the planktonic foraminiferal assemblages has led to the recognition of twelve Upper Cretaceous zones (Helvetoglobotruncana helvetica Zone to the Contusotruncana contusa-Abathomphalus mayaroensis zone) from the Tethyan realm. The obtained stable carbon isotope profile correlates with other reference curves, revealing many Late Cretaceous events including the Hitchwood, Navigation, Light Point, East Cliff, White Fall, Late Campanian Event (LCE), Campanian-Maastrichtian Boundary Event (CMBE), Middle Maastrichtian Event (MME) and KPg Events (KPgE). The Turonian-Maastrichtian deposits of the studied area represent severe changes in sedimentation rate and several hiatuses and condensed intervals, which mostly coincide with lithological boundaries. The data indicate a general shallowing -upwards in association with the Late Cretaceous tectonics of the Kopet-Dagh Basin. The reconstruction of the age model allows a discussion of the results in terms of changes in palaeoenvironmental conditions (eutrophic vs. oligotrophic).

The AND-1B drill core (1285m-long) was recovered, inside the ANDRILL (ANtarctic geological DRILLing) Program, during the austral summer of 2006/07 from beneath the floating McMurdo Ice Shelf. Drilling recovered a stratigraphic succession of alternating diamictites, diatomites and volcaniclastic sediments spanning about the last 14Ma. A core portion between 350 and 480mbsf, including a 80m-thick diatomite interval recording the early Pliocene warming event, was investigated in term of opal biogenic content and element geochemistry. Across the diatomite interval, in spite of the lithological uniformity, a fluctuating biogenic opal profile mirrors the δ18O record, testifying a decrease in productivity when temperature drops as a consequence of small glacial fluctuations. The comparison of biogenic opal data with Chaetoceros spp. abundances from Konfirst et al. (2012) documents alternations between periods of high primary productivity in stratified surface waters and of enhanced terrigenous input in ice-free conditions. Cluster analysis discriminates elements associated to terrigenous input from those subject to biogenic control. Further separation in sub-cluster was interpreted in term of different element response to changes in provenance but also to depositional/early diagenetic conditions at the seafloor. Whilst K and Ti are related to different sediment sources confirming previous studies from the same interval, V, Zn and, to a lesser extent, Fe, document reducing/anoxic conditions during the diatomites deposition (in particular in 400-460mbsf interval). Mg, Sr and Mn contents are related to authigenic carbonate precipitation whilst Ba is interested by nonsteady-state processes leading to local peaks of barium below the sulphate-rich/sulphate-poor pore water boundary where generally the low degree of barite saturation is responsible for Ba remobilization. Such alteration in depositional dynamics, responsible of the precipitation of an oxygen-depleted barium phase, was probably induced by change in sedimentation rate and/or in palaeoenvironmental conditions. © 2013 Elsevier B.V.

A number of carbonate mounds composed of indurate, strongly folded and/or brecciated calcite and dolomite beds occur interstratified in Cenozoic sedimentary sequences from the Las Minas Basin. Part of the fabric of the rock forming the carbonate mounds is composed of laminated to banded dolostone similar to the host rock but showing contrasted lithification. Moreover, the carbonate deposits of the mounds display aggrading neomorphism of dolomite, partial replacement of dolomite by calcite, calcite cementation, and extensive silicification, locally resulting in box-work fabric. Eight main lithofacies were distinguished in the carbonate mound deposits. In some lithofacies, chert is present as both microcrystalline to fibro-radial quartz and opal, the latter occurring mainly as cement whereas the former replace the carbonate and infill voids. Yet one of the carbonate mounds shows distinctive petrography and geochemical features thus suggesting a distinctive growth pattern. The carbon isotope compositions of calcite from the mound samples range from − 11.56 to − 5.15 δ‰ whilst dolomite is depleted in 13C, with values of − 12.38 to 3.02 δ‰. Oxygen isotopic compositions vary from − 9.42 to − 4.64 δ‰ for calcite and between − 6.68 and 8.19 δ‰ for dolomite. Carbonate in the mounds shows significant enrichment in Co, Cr, Ni and Pb content, especially in the strongly deformed (F-2-2 lithofacies) and brecciated carbonate (F-4). The carbonate deposits show depletion in REE and Y in contrast to that determined in lutite. The formation of the carbonate mounds was related to local artesian seepage thermal water flows of moderate to relative high temperatures. Pressure differences between the low permeability host rock and the circulating fluids accounted for dilational fracturing and brecciation of the host sediment packages, which combined with precipitation of new carbonate and silica mineral phases. Locally, some carbonate mounds developed where groundwater intersected the lake floor, this resulting in bedded carbonate deposits composed of organic constituents.

A large portion of ANDRILL (ANtarctic geological DRILLing) core AND-1B recovered in the Western Ross Sea and spanning the early Pliocene has been investigated in order to obtain a detailed carbonate isotope record from Antarctic margin sediments through the early Pliocene warming event. Petrographic observations and mineralogical analyses reveal the authigenic nature of the carbonate and small proportions of Fe and Mg incorporated within the calcite lattice. High productivity conditions testified by ~ 80 m-thick diatomite interval (383 to 460 mbsf) well fit with the composite nature of the authigenic carbonate generally characterizing organic matter-rich sediments. As is known, sediments from the Polar Region are generally poor in carbonate. Although in the investigated portion of AND-1B core the carbonate seldom exceeds 5% in content, an automated Carbonate Preparation Device was used to obtain a high-resolution stable isotope dataset. Paleoenvironmental conditions characterized by high organic matter flux are supported by negative δ13C values suggesting a contribution of isotopically light biogenic CO2 during the carbonate precipitation. As to δ18O, even if melting glaciers are thought to be responsible for depletion in 18O composition, the isotope record exhibits long- and short-term trends. Analysis of the long-term trend constrains the Pliocene warming climax in an interval between 400–450 mbsf highlighting that most of the event is not documented because of a 800 kyr hiatus. The short-term trend documents the influence of obliquity controlling the annual insolation, but also that of precession-linked cyclicity seldom documented at high latitude.

Granulometry, mineralogy, and trace element concentrations are determined in marine sediments from thirty-six sampling sites in the littoral environment of the Gulf of Milazzo (NE Sicily). Sediment samples were collected in August 2008, along 18 seaward transects, at water depths of ‐10, ‐20 and ‐30 m, by using a Van Veen grab. Grain-size analysis shows predominance of sand (56%) and silt (35%) fractions with respect to clay (7%) and gravel (2%) fractions. Bulk mineralogical analysis documents the presence of quartz, micas, feldspars, calcite, and chlorite, which reflect erosion processes affecting the Kabilian-Calabrian Units. Concentrations of most trace elements in the deeper sediments were notably higher than shallower ones, due to the gradual increase of the fine fraction (

Phosphogenesis at the base of the Bonarelli Level from the Calabianca stratigraphic section (northwestern Sicily) was investigated using X-ray diffraction, scanning electron microscopy, X-ray fluorescence, and stable-isotope mass spectrometry. The anoxic event onset is marked by high P(2)O(5tot) concentrations related to the presence of authigenic carbonate-fluorapatite. This mineral is poorly crystallized and occurs in three different forms: (i) fish debris locally showing evidence of re-crystallization, (ii) phosphatically cemented layers, and (iii) dense aggregates of microcrystals. Petrographic features are indicative of a microbial genesis for the carbonate-fluorapatite. Conversely, this evidence is lacking in phosphate from the upper part of the section, where lower P(2)O(5tot) concentrations are linked to the presence of sparse unaltered hydroxy-apatite fish debris. Distribution patterns of rare earth elements (REE) throughout the Calabianca section, the Ce anomaly and V/(V + Ni) values suggest fluctuating redox conditions during phosphogenesis. These conditions triggered the iron redox cycle that operated as phosphate sink-switching mechanism. Depth profiles of P mass accumulation rate and C-isotope compositions highlight the decoupling of P and C-org cycles, whose global implication is confirmed by correlation with the same proxies from other well known stratigraphic sections, which embody sedimentary expressions of the Oceanic Anoxic Event 2 (OAE2). (C) 2009 Elsevier Ltd. All rights reserved.

High-resolution micropalaeontological and chemostratigraphic records for the upper Cenomanian portion of the Calabianca–Guidaloca composite section (NW Sicily) provide new insight into the palaeoclimatic and palaeoceanographic evolution of the Tethys Ocean. The Bonarelli Level equivalent was identified on the basis of lithology and well constrained by calcareous plankton biostratigraphy and radiolarian assemblages, as well as by the δ 13 C curve showing a marked positive excursion (up to 4.7‰). The Bonarelli Level equivalent deposition is characterized by highly eutrophic conditions as testified by radiolarian proliferation. Black shale samples from the Calabianca–Guidaloca composite section contain very high TOC (up to 26%) and moderate to high amounts of CaCO 3 (on average 20%). Among the planktonic foraminifera, hedbergellids and globigerinelloids tolerated the environmental stress induced by the Oceanic Anoxic Event 2 (OAE2). The occurrence of some benthic foraminifera testifies to dysoxic rather than completely anoxic conditions at the sea floor during the deposition of some portions of the Bonarelli Level equivalent. Based on micropalaeontological results and geochemical proxies ( δ 13 C, D *, Rb, Ti, V, Ni, Ba, Si, Cr), the Bonarelli Level equivalent is interpreted as a high-productivity event driven by increasingly warm and humid climatic conditions promoting an accelerated hydrological cycle. We propose that periodically increased riverine influxes, triggered by enhanced humidity, resulted in a sluggish circulation mode and consequent anoxic/euxinic conditions favouring the preservation of organic matter at the sea-floor. Spectral analyses performed on selected geochemical signals reveal within the main high productivity event a strong orbital–climatic forcing represented by a long-term eccentricity-steered humidity cyclicity that amplifies a short-term precession-controlled productivity fluctuation.