600 research outputs found

    Characterization of the cellular damage induced by Aflatoxin B1 in sea bream (Sparus aurata Linnaeus, 1758) hepatocytes

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    Gilthead sea bream (Sparus aurata L.) is one of the most intensively farmed fish spe- cies in the Mediterranean, greatly studied for the relevant economic value, although its sensitivity to Aflatoxin B1 (AFB1) has to be investigated, yet. The aim of this study was to perform an in vitro evalua- tion of cytotoxic potential of AFB1 on S. aurata hepatocytes in order to grade the range of AFB1 toxicity, and the boundary between acute and long-term toxicity. Primary monolayer cultures of hepatocytes from S. aurata juveniles were treated with a wide range of concentrations from 5x103 ng/ml to 2x10 2x10-5 ng/ml of AFB1 for a different period of exposure (24, 48, 72 hours). The cytotoxic activity was characterized by MTT reduction assay. After each exposition hepatocytes were examined for morphologic alterations and apoptosis induction. AFB1 exposure significantly reduced cell viability in a dose- and time-depend- ent manner. Dose-response curves obtained after 24, 48 and 72 hrs revealed that prolonged exposure times lead to a significant increase of the toxicpotencyofAFB toxic potency of AFB AFB1. Ourresultsdemonstratethat Our results demonstrate that S. aurata hepatocytes are highly sensitive to AFB1 exposure. Such scientific findings could provide new insights to investigate the real impact of aflatoxin on marine farmed fish

    Volcaniclastic debris flow occurrences in the Campania region (southern Italy) and their relation to Holocene - late Pleistocene pyroclastic fall deposits: implications for large scale hazard mapping

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    The Campania Region (Southern Italy) is characterized by the frequent occurrence of volcaniclastic debris flows that produce damage to property and loss of life (more than 170 deaths between 1996 and 1999). Historical investigation allowed the identification of more than 500 events during the last four centuries; in particular, more than half of these occurred in the last 100 years, causing hundreds of deaths. The aim of this paper is to identify debris flow proneness and to quantify hazard. To this end, we compared several elements such as the thickness distribution of pyroclastic fall deposits from the last 18 ka of the Vesuvius and Phlegrean Fields volcanoes, the slopes of relieves, and the historical record of volcaniclastic debris flows from AD 1500 to the present. Results show that flow occurrence is not only a function of the cumulative thickness of past pyroclastic fall deposits but also depends on the age of emplacement. Deposits younger than 10 ka (Holocene eruptions) apparently increase the risk of debris flows, while those older than 10 ka (Late Pleistocene eruptions) seem to play a less prominent role. This is probably in relation to different climatic conditions, and therefore different rates of erosion of pyroclastic falls between the Holocene and the Late Pleistocene. Based on the above considerations, we compiled a large-scale debris flow hazard map of the study area in which five main hazard zones are identified: very low, low, moderate, high and very high

    Behaviour of adenylic and pyridinic compounds in gingival tissue after a short-term exposure to air

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    Biochemical variations of adenine and pyridine compounds in human gingival grafts during the period between excision and implantation have been studied. These groups of compounds are considered as «indicators» of the metabolic and energetic status of the living cells. Adenylic compounds such as ATP, ADP and AMP are involved in numerous metabolic processes as «modulators» of allosteric enzymes.NAD+ and NADP+ are involved in the carbohydrate metabolism as co-factors of many reactions of oxydoreduction. The exposure to air of the gingival tissue induces modifications in the energy state of the cells as well as in the ox-reox system. No variation is detectable in the intermediates of the pyridine compounds cycle.Dans des gencives humaines prĂ©levĂ©es pour des greffes, ont Ă©tĂ© Ă©tudiĂ©es, Ă  certains intervalles de temps entre le prĂ©lĂšvement et la greffe, les variations biochimiques des composĂ©s adĂ©nyliques et pyridiniques, qui sont les «indicateurs» des conditions Ă©nergĂ©tiques et mĂ©taboliques du tissu. Des composĂ©s comme l’ATP, l’ADP et l’AMP participent Ă  de nombreux processus mĂ©taboliques comme «modulateurs» des enzymes allostĂ©riques. NAD+ et NADP + participent au mĂ©tabolisme des carbohydrates comme co-facteurs de nombreuses rĂ©actions d’oxydorĂ©duction. Une brĂšve exposition de la gencive Ă  l’air provoque des changements dans le mĂ©tabolisme des cellules et du systĂšme d’oxydorĂ©duction. Il n’y a pas de variation notable dans les composĂ©s intermĂ©diaires du cycle pyridinique

    Comment on: ‘‘The dark nature of Somma-Vesuvius volcano:Evidence from the 3.5 ka BP Avellino eruption’’ by Milia A.Raspini A., Torrente M.M.,

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    We present here some criticism to the scientific content of the paper of Milia et al. [2007. The dark nature of Somma-Vesuvius volcano: evidence from the 3.5 ka B.P. Avellino eruption. Quaternary International, 173–174, 57–66] published in Quaternary International. Milia et al. (2007) interpreted seismic lines in the Gulf of Naples (southern Italy), and inferred the presence of deposits from a large debris avalanche which occurred just before the Avellino eruption of Somma-Vesuvius volcano. The authors supported their seismic profile interpretation with on-land stratigraphies and logs. However, we present here different on-land data that demonstrate the inconsistency of the occurrence of any debris avalanche before or after the Avellino eruption, and we provide also an alternative interpretation for the observed seismic facies offshore of Somma-Vesuvius

    The Endocannabinoid System: A Putative Role in Neurodegenerative Diseases

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    BACKGROUND: Following the characterization of the chemical structure of D9-tetrahydrocannabinol (THC), the main psychoactive constituent of marijuana, researchers have moved on with scientific valuable explorations. OBJECTIVES: The aim of this review is to highlight the role of endocannabinoid system in neurodegenerative diseases. MATERIALS AND METHODS: The article is a critical analysis of the most recent data currently present in scientific literature on the subject; a qualitative synthesis of only the most significant articles has been performed. RESULTS: In central nervous system, endocannabinoids show a neuromodulatory function, often of retrograde type. This way, they play an important role in synaptic plasticity and in cognitive, motor, sensory and affective processes. In addition, in some acute or chronic pathologies of central nervous system, such as neurodegenerative and neuroinflammatory diseases, endocannabinoids can perform a pro-homeostatic and neuroprotective function, through the activation of CB1 and CB2 receptors. Scientific evidence shows that an hypofunction or a dysregulation of the endocannabinoid system may be responsible for some of the symptoms of diseases such as multiple sclerosis, amyotrophic lateral sclerosis, Huntington’s, Parkinson’s and Alzheimer’s diseases. CONCLUSIONS: The important role played by endocannabinoid system promises interesting developments, in particular to evaluate the effectiveness of new drugs in both psychiatry and neurology

    Assessing pyroclastic fall hazard through field data and numerical simulation: Example from Vesuvius

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    A general methodology of pyroclastic fall hazard assessment is proposed on the basis of integrated results of field studies and numerical simulations. These approaches result in two different methods of assessing hazard: (1) the ‘‘field frequency,’’ based on the thickness and distribution of past deposits and (2) the ‘‘simulated probability,’’ based on the numerical modeling of tephra transport and fallout. The proposed methodology mostly applies to volcanoes that, by showing a clear correlation between the repose time and the magnitude of the following eruptions, allows the definition of a reference ‘‘maximum expected event’’ (MEE). The application to Vesuvius is shown in detail. Using the field frequency method, stratigraphic data of 24 explosive events in the 3–6 volcanic explosivity index range in the last 18,000 years of activity are extrapolated to a regular grid in order to obtain the frequency of exceedance in the past of a certain threshold value of mass loading (100, 200, 300, and 400 kg/m2). Using the simulated probability method, the mass loading related to the MEE is calculated based on the expected erupted mass (5 1011 kg), the wind velocity profiles recorded during 14 years, and various column heights and grain-size populations. The role of these factors was parametrically studied performing 160,000 simulations, and the probability that mass loading exceeded the chosen threshold at each node was evaluated. As a general rule, the field frequency method results are more reliable in proximal regions, provided that an accurate database of field measurements is available. On the other hand, the simulated probability method better describes events in middle distal areas, provided that the MEE magnitude can be reliably assumed. In the Vesuvius case, the integration of the two methods results in a new fallout hazard map, here presented for a mass loading value of 200 kg/m2

    A comprehensive overview on Kratom

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    Kratom (Mitragyna speciosa Korth) is a tropical tree, indigenous to South East Asia. Historically, the plant is locally used as a stimulant, a remedy in traditional medicine and in social context. Imported to Western countries, Kratom is classified as a novel psychoactive substance (NPS). A systematic review of the literature on Mitragyna speciosa and its main constituents was carried by our international multidisciplinary group. Results were qualitatively analysed in three main areas of interest: in-vitro and preclinical data on pharmacology and behavioral effects, laboratoristic techniques for identification/characterization, epidemiological/toxicological reports on humans. At present, there is no systematic data on the prevalence of Kratom use in all the native countries, but it seems to be considerable. In South-East Asia, Kratom, even if banned, might be still considered a better option than other illicit drugs, an alternative opioid treatment, a “natural” remedy with no real social stigma attached to its consumption. In parallel, this ethno-drug seems to be popular in Western countries, largely unregulated, easily available on the Internet. Kratom pharmacology appears to be complex, with many alkaloids involved. The subjective effects in humans are very peculiar and seem to be dose-dependent, ranging from psycho-stimulant to sedative-narcotic. Available data on Kratom suggest caution: this psychoactive plant could exhibit a serious harmful potential. Kratom use seems to be associated with drug dependency, development of withdrawal symptoms, craving, serious adverse effects and life-threatening effects in a multidrug-intoxicating scenario. On the other hand, its anxyiolitic, antidepressant and analgesic properties deserve to be further studied

    Sopravvivenza di microrganismi potenzialmente patogeni su superfici porcellanate

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    È stata valutata la capacità di sopravvivere sulla superficie inerte porcellanata di tazzine da caffÚ di quattro microrganismi potenzialmente patogeni (Streptococcus pyogenes, Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli). Dopo inoculazione Ú stata dimostrata capacità di sopravvivenza fino a 24 ore di Streptococcus pyogenes, Staphylococcus aureus ma non di Pseudomonas aeruginosa, Escherichia coli. Questi dati suggeriscono il potenziale ruolo patogeno giocato dalle superfici di stoviglie di largo uso nella trasmissione di infezioni da alcuni microrganismi gram-positivi

    Celecoxib Adjunctive Treatment to Antipsychotics in Schizophrenia: A Review of Randomized Clinical Add-On Trials

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    Schizophrenia is a severe, chronic and debilitating mental disorder. Past literature has reported various hypotheses about the psychopathology of schizophrenia. Recently, a growing literature has been trying to explain the role of inflammation in the etiopathogenesis of schizophrenia. In the past, numerous immune modulation and anti-inflammatory treatment options have been proposed for schizophrenia, but sometimes the results were inconsistent. Electronic search was carried out in November 2015. PubMed and Scopus databases have been used to find studies to introduce in this review. Only randomized-placebo-controlled add-on trials were taken into account. In this way, six articles were obtained for the discussion. Celecoxib showed beneficial effects mostly in early stages of schizophrenia. In chronic schizophrenia, the data are controversial, possibly in part for methodological reasons
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