205 research outputs found
Iron ore deposits in the central Southern Alps (Lombardy, Italy): lithostratigraphic and metallogenic reassessment
No full textThe central Southern Alps host a very extensive metallogenic province including different metalliferous districts which are characterised by the prevailing presence of Fe, Pb-Zn ores, fluorite, and barite. The dominant iron district showing siderite-ankerite and minor hematite and sulphides is strictly space- and time-controlled. It runs from east to west, between Lake Lugano and Lake Iseo (Giudicarie Line), and includes several iron deposits, both of syngenetic-stratiform and epigenetic vein and dissemination type (fig. 1; tabs. 1, 2, 3). Such deposits were formed during a metallogenic epoch involving the Ordovician-Silurian upper portion of the crystalline basement and the volcano-sedimentary cover formations defined, from bottom to top, by: (i) the Carboniferous-Lower Permian Basal Conglomerate Fm, (ii) the Lower Permian Collio Fm, (iii) the Upper Permian Verrucano Lombardo Fm, (iv) the Lower Triassic Servino Fm. Concerning ore genesis (the depositional environment, transport of hydrothermal fluids, generation of hydrothermal ore fluids and constituents) of the syngenetic-strati form iron mineralization in the different lithostratigraphic sequences, the following observations can be deduced: (a) the presence of a common sub-littoral marine coastal to more distal depositional environment which was CO2-rich and locally hypersaline. This was set in a shallow carbonate-producing shelf zone with contributions of terrigenous as well as magmatogenic material. Local environments include lacustrine and evaporitic (upper member of the Collio Formation), together with a continental alluvial environment for the placer deposit of the >; (b) with respect to iron concentration in the depositional sites, there is evidence for a cyclic transport mechanism by hydrothermal systems, strictly connected to synsedimentary transtensive tectonics; (c) the generation of hydrothermal iron-enriched fluids can be referred to the dissolved content of both accessory and essential iron-bearing minerals of pre-existing rocks, leached and transported under suitable Eh-pH conditions. The genetic points common to epigenetic vein and disseminated mineralization are: (a) fault systems and fractures and permeable lithologies such as conglomerates, sandstones, cataclasites can act as suitable sites of deposition; (b) because of the spatial relationships existing between the epigenetic deposits and the late-Hercynian heat engines, the main mobilisation of the metal solutions (of meteoric, metamorphic and diagenetic origin) can be assumed to be hydrothermal >; a minor remobilization > of meteoric waters and chiefly of syn- to late-diagenetic hydrothermal fluids entirely affects every iron formation, especially the Servino Fm, which marks the upper limit of the iron metallogenesis; (c) the iron source can be envisaged in the leaching of any kind of pre-existing rocks, including the iron formations occurring within the sequence. On the question of iron source, the metal zoning of the basement of the Southern Central Alps can be taken into account (BRIGO & OMENETTO, 1979). Such basement is defined, from west to east, respectively, by a Au-zone (Strona Ceneri Zone), a Fe-zone (central Southern Alps), a pyrite-zone (Trentino Alto Adige Region), and a Cu-pyrite-zone (Cadore-Belluno Province). With respect to a general picture of the iron metallogenesis in the Alps, it is important to notice (BRIGO, 1998) that the deposits in the central Southern Alps are correlated with the iron deposits of the >, Styria, in the Northern Grauwacken Zone (THALMANN, 1979; SCHULZ et alii, 1997). On taking the recent investigations of the Authors into account, together with a critical literature revision of geology and of ore geology (JERVIS, 1873; CURIONI, 1877; CORNELIUS, 1916; STELLA, 1921; PENTA, 1952; MICHELETTI, 1954; GILLIERON, 1959; ASSERETO & CASATI, 1965; OMENETTO & BRIGO, 1974; FRIZZO & OMENETTO, 1974; FUMASOLI, 1974; BRIGO & OMENETTO, 1979; BERTOTTI et alii, 1993; CASSINIS el alii, 1997; SCIUNNACH et alii, 1999; SPALLA & GOSSO, 1999; SPALLA et alii, 1999; JADOUL et alii, 2000; SPALLA et alii, 2000), as well as an important re-evaluation of the extensive series of scientific works of historical, technological and archaeological nature (MAIRONI DA PONTE, 1803; ARRIGONI, 1840; CESA BIANCHI, 1874; FRUMENTO, 1952-1963; SQUARZINA, 1960; COLOMBO, 1976; TIZZONI, 1994-1995, 1997), it is possible to attain considerable evidence for a general theory concerning the origin of stratiform iron-bearing mineralizations or stratigraphic markers in different geological units especially occurring in the crystalline basement. As a consequence, the extension of this iron-bearing district in the Alps consisting of a dense distribution of small concentrations attains about 1900 km(2); such a pattern accounts for the presence of intense mining, metallurgical and artisanal activities which have taken place beginning from a remote origin until the first half of the XXth century, accounting for the present world-wide important social and economic position of Lombardy region
Neurostimulation in the treatment of refractory and super-refractory status epilepticus
No full textStatus epilepticus (SE) is a life-threatening condition with a mortality of up to 60% in the advanced and comatose forms of SE. In one out of five adults, first and second line fails to control epileptic activity, leading to refractory status epilepticus (RSE) and in around 3% to super-refractory status epilepticus (SRSE), where SE continues despite anesthetic treatment for 24 h or more. In this rare but devastating condition, innovative and safe treatments are needed. In a recent review on the use of vagal nerve stimulation in RSE and SRSE, a 74% response rate for abrogation of SE was reported. Here, we review the currently available evidence supporting the use of neurostimulation, including vagal nerve stimulation, direct cortical stimulation, transcranial magnetic stimulation, electroconvulsive therapy, and deep brain stimulation in RSE and SRSE. This article is part of the Special Issue "Proceedings of the 7th London-Innsbruck Colloquium on Status Epilepticus and Acute Seizures"
Google search behavior for status epilepticus.
No full textBackground: Millions of people surf the Internet every day as a source of health-care information looking for materials about symptoms, diagnosis, treatments and their possible adverse effects, or diagnostic procedures. Google is the most popular search engine and is used by patients and physicians to search for online health-related information. This study aimed to evaluate changes in Google search behavior occurring in English-speaking countries over time for the term “status epilepticus” (SE).
Methods: Using Google Trends, data on global search queries for the term SE between the 1st of January 2004 and 31st of December 2014 were analyzed. Search volume numbers over time (downloaded as CSV datasets) were analyzed by applying the “health” category filter.
Results: The research trends for the term SE remained fairly constant over time. The greatest search volume for the term SE was reported in the United States, followed by India, Australia, the United Kingdom, Canada, the Netherlands, Thailand, and Germany. Most terms associated with the search queries were related to SE definition, symptoms, subtypes, and treatment. The volume of searches for some queries (nonconvulsive, focal, and refractory SE; SE definition; SE guidelines; SE symptoms; SE management; SE treatment) was enormously increased over time (search popularity has exceeded a 5000% growth since 2004).
Conclusions: Most people use search engines to look for the term SE to obtain information on its definition, subtypes, and management. The greatest search volume occurred not only in developed countries but also in developing countries where raising awareness about SE still remains a challenging task and where there is reduced public knowledge of epilepsy.
Health information seeking (the extent to which people search for health information online) reflects the health-related information needs of Internet users for a specific disease. Google Trends shows that Internet users have a great demand for information concerning some aspects of SE (definition, subtypes, symptoms, treatment, and guidelines). Policy makers and neurological scientific societies have the responsibility to try to meet these information needs and to better target public information campaigns on SE to the general population
“Chi l’ha detto?”. Un caso emblematico di errata attribuzione
No full textThis article discusses the real authorship of a sentence erroneously attributed to Giovanni Battista Morgagni (1682-1771) but actually by the French physician François Joseph Victor Broussais (1772-1838). This exemplary case shows how a single erroneous attribution risks being reproposed over time, consolidating itself in the scientific literature, so much to replace the original authorship with an erroneous one. It follows the absolute necessity to always and rigorously verify the accuracy of a sentence attributed to a certain author, both in form and in content, as well as in its real authorship.In questo articolo si presenta e discute la reale paternità di una frase erroneamente attribuita a Giovanni Battista Morgagni (1682-1771) e in realtà del medico francese François Joseph Victor Broussais (1772-1838). Questo caso emblematico evidenzia come una singola attribuzione errata rischi di essere riproposta nel tempo consolidandosi nella lettera-tura scientifica, tanto da sostituire la paternità originaria con una erronea. Ne consegue l’assoluta necessità di verificare sempre e in maniera rigorosa l’accuratezza di un’espressione attribuita a un autore, sia nella forma che nel contenuto, oltre che nella sua reale paternità
Intravenous antiepileptic drugs in adults with benzodiazepine-resistant convulsive status epilepticus: A systematic review and network meta-analysis
No full textAIM: The aim of this study was to estimate the comparative efficacy and safety of antiepileptic drugs (AEDs) in adults with benzodiazepine-resistant convulsive status epilepticus (SE). METHODS: MEDLINE, CENTRAL, ClinicalTrials.gov, and Opengrey.eu were searched (from inception to 3rd April, 2018) for randomized controlled trials (RCTs) of AEDs used intravenously to treat benzodiazepine-resistant SE in adults. Efficacy outcomes were SE cessation within 1 h from drug administration and seizure freedom at 24 h. Safety outcomes were respiratory depression and hypotension. Effect sizes were estimated by network meta-analyses within a frequentist framework. The hierarchy of competing interventions was established using the surface under the cumulative ranking curve (SUCRA) and mean ranks. RESULTS: Five RCTs were considered, involving 349 patients. Included interventions were valproate (VPA; 20-30 mg/kg), phenytoin (PHT; 20 mg/kg), diazepam (DZP; 0.2 mg/kg, then 4 mg/h), phenobarbital (PHB; 20 mg/kg, then 100 mg every 6 h), lacosamide (LCM; 400 mg), and levetiracetam (LEV; 20 mg/kg); PHB was superior to PHT, VPA, DZP, LEV, and LCM with respect to SE cessation and performed better than VPA, DZP, and LCM in the achievement of seizure freedom at 24 h. No differences were noted between drugs in the occurrence of respiratory depression and hypotension. According to SUCRA, PHB had the greatest probabilities of being best in the achievement of SE control and seizure freedom, whereas VPA and LCM ranked best for the safety outcomes. CONCLUSIONS: Our study suggests that high-dose PHB is effective in controlling SE and preventing seizure recurrence, and LCM and VPA could be better tolerated options. Further head-to-head comparative studies are strongly required to provide more definitive evidence. This article is part of the Special Issue "Proceedings of the 7th London-Innsbruck Colloquium on Status Epilepticus and Acute Seizures"
Statins in primary prevention of poststroke seizures and epilepsy: A systematic review
No full textIntroduction: Cerebrovascular disease is the most common cause of seizures in adults and the elderly. So far, no drug is recommended as primary prevention of acute symptomatic poststroke seizures (ASPSS) or poststroke epilepsy (PSE). This systematic review aimed to evaluate the association between the use of statins after stroke and the risk of developing ASPSS or PSE following cerebral infarct or hemorrhage (primary prevention). Methods: We included studies evaluating the poststroke use of statins as primary prevention of ASPSS or PSE, irrespective of stroke type. We excluded uncontrolled studies and studies with prestroke statin use. The main outcome included the occurrence of ASPSS or PSE and the effect of statins by type and dose. The odds ratios (ORs) or hazard ratios (HR) with 95% confidence intervals (CIs) were used as the measures of association between treatment and outcome. Results: Four studies were included. One study showed a reduced risk of ASPSS after ischemic stroke (OR: 0.25; 95% CI: 0.10–0.59; p = 0.0016). Three studies consistently reported a reduced risk of PSE after ischemic stroke, and one study a reduced risk of PSE after hemorrhagic stroke (HR: 0.62; 95% CI: 0.42–0.90; p = 0.01). Conclusions: Data from the literature suggest an association between statin use and a reduced risk of ASPSS after ischemic stroke and a reduced risk of PSE after ischemic and hemorrhagic stroke. Although the certainty of the evidence is low, these findings appear promising and worthy of further investigation
Effects of phenyl salygenin phosphate (PSP) and phenylmethane sulfonyl fluoride (PMSF) on rat dorsal root canglia (DRG) cultures
No full textB-mode transorbital ultrasonography for the diagnosis of idiopathic intracranial hypertension: an updated systematic review and meta-analysis
No full textObjectivesThis systematic review and meta-analysis aimed to evaluate the role of B-mode transorbital ultrasonography (TOS) for the diagnosis of idiopathic intracranial hypertension (IIH) in adults.MethodsMEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials (CENTRAL) (1966-May 2022) were searched to identify studies reporting ultrasonographic data about the optic nerve sheath diameter (ONSD) and optic disc elevation (ODE) in adults with IIH compared to subjects without IIH. The quality of the included studies was evaluated by the Newcastle-Ottawa Quality.ResultsFifteen studies were included (total of 439 patients). The values of ODE ranged from 0.6 to 1.3 mm in patients with IIH. The values of ONSD ranged from 4.7 to 6.8 mm in IIH patients and from 3.9 to 5.7 mm in controls. In IIH patients, the ONSD was significantly higher compared to controls (standardized mean difference: 2.5 mm, 95% confidence interval (CI): 1.6-3.4 mm). Nine studies provided data about the presence of papilledema and the pooled prevalence was 95% (95% CI, 92-97%).ConclusionsIn adults, the thickness of ONSD and the entity of ODE were significantly associated with IIH. B-mode TOS enables to noninvasively detect increased ICP and should be performed, potentially routinely, in any patient with suspected IIH
Common Correlation and Calibrating the Lognormal Forward Rate Model
No full text1997 three papers that introduced very similar lognormal diffusion processes for interest rates appeared virtuously simultaneously. These models, now commonly called the 'LIBOR models' are based on either lognormal diffusions of forward rates as in Brace, Gatarek & Musiela (1997) and Miltersen, Sandermann & Sondermann (1997) or lognormal diffusions of swap rates, as in Jamshidian (1997). The consequent research interest in the calibration of the LIBOR models has engendered a growing empirical literature, including many papers by Brigo and Mercurio, and Riccardo Rebonato (www.fabiomercurio.it and www.damianobrigo.it and www.rebonato.com). The art of model calibration requires a reasonable knowledge of option pricing and a thorough background in statistics - techniques that are quite different to those required to design no-arbitrage pricing models. Researchers will find the book by Brigo and Mercurio (2001) and the forthcoming book by Rebonato (2002) invaluable aids to their understanding.
Quantitative correlation of solvent polarity with the alpha-/3(10)-helix equilibrium: A heptapeptide behaves as a solvent-driven molecular spring
No full textThe long and the short of it: Just by changing the polarity of the solvent the highly folded heptapeptide Ac-[Aib-L-(αMe)Val-Aib]2-L-His-NH2 converts from an α into a 310 helix (see picture). The equilibrium constant between the two conformations correlates with the empirical solvent polarity parameter Eequation image. Molecular dynamics calculations show that the peptide elongates (310 helix) or shortens (α helix) on switching from one conformation to the other
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