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1.
Sci Rep ; 13(1): 22855, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38129450

RESUMO

Alteration of basaltic glass and in situ mineral growth are fundamental processes that influence the chemical and material properties of Earth's oceanic crust. These processes have evolved at the basaltic island of Surtsey (SW Iceland) since eruptions terminated in 1967. Here, subaerial and submarine lapilli tuff samples from a 192 m-deep borehole drilled in 2017 (SE-02b) are characterized through petrographic studies, X-ray powder diffraction analyses, and SEM-EDS imaging and chemical analyses. The integrated results reveal (i) multi-stage palagonitization processes in basaltic glass and precipitation of secondary minerals from matrix pore fluids, (ii) multi-stage crystallization of secondary phillipsite, analcime and Al-tobermorite in the vesicles of basaltic pyroclasts and (iii) variations in palagonitization processes as a function of thermal and hydrological domains. Although temperature appears to be an important factor in controlling rates of secondary mineralization, the chemistry of original basaltic components and interstitial fluids also influences reaction pathways in the young pyroclastic deposits. The integration of systematic mineralogical analyses of the 50-year-old tuff from one of the most carefully monitored volcanic sites on Earth, together with temperature monitoring in boreholes since 1980, provide a reference framework for evaluating mineralogical evolution in other Surtseyan-type volcanoes worldwide.

2.
Materials (Basel) ; 15(7)2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35408016

RESUMO

The present paper assesses petrographic, mineralogical, chemical, and technological features of different zeolitic tuff samples from various western USA districts of the Basin and Range Province containing mainly erionite, mordenite, clinoptilolite/heulandite and phillipsite. The aim of this characterization is to evaluate the pozzolanic activity of these samples according to European normative UNI-EN 196/5 (Fratini test) to program a possible use as addition for blended cements. Petrographic and mineralogical results show that the two phillipsite-bearing tuffs have a higher theoretical Cation Exchange Capacity (CEC) than the other samples; technological characterization shows a pozzolanic behavior for all the samples but higher for the tuff samples containing phillipsite, which shows a higher reactivity with CaO. All the samples could be thus advantageously employed for the preparation of blended cements, potentially reducing CO2 emissions by 70-90%.

3.
Br J Clin Pharmacol ; 88(7): 3495-3499, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35083767

RESUMO

TCC is a semisynthetic molecule widely used in clinical settings as a pain killer and myorelaxant. Several neurological side effects have been reported in association with TCC treatment including somnolence, confusion and seizure, the latter in a lower percentage of patients. Some previous reports described seizure onset after TCC intake in adulthood. However, major epileptological complication, namely status epilepticus, has never been previously reported in association with TCC treatment. In our report, we describe a case of acute refractory non-convulsive status epilepticus (NCSE) in the context of a TCC-induced acute toxic encephalopathy (ATE) in a woman without any previous neurological or physical comorbidities.


Assuntos
Estado Epiléptico , Adulto , Colchicina/efeitos adversos , Colchicina/análogos & derivados , Eletroencefalografia , Feminino , Humanos , Injeções Espinhais/efeitos adversos , Convulsões/tratamento farmacológico , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/complicações , Estado Epiléptico/tratamento farmacológico
4.
Trials ; 17: 414, 2016 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-27538798

RESUMO

BACKGROUND: Although beneficial in clinical practice, the INtubate-SURfactant-Extubate (IN-SUR-E) method is not successful in all preterm neonates with respiratory distress syndrome, with a reported failure rate ranging from 19 to 69 %. One of the possible mechanisms responsible for the unsuccessful IN-SUR-E method, requiring subsequent re-intubation and mechanical ventilation, is the inability of the preterm lung to achieve and maintain an "optimal" functional residual capacity. The importance of lung recruitment before surfactant administration has been demonstrated in animal studies showing that recruitment leads to a more homogeneous surfactant distribution within the lungs. Therefore, the aim of this study is to compare the application of a recruitment maneuver using the high-frequency oscillatory ventilation (HFOV) modality just before the surfactant administration followed by rapid extubation (INtubate-RECruit-SURfactant-Extubate: IN-REC-SUR-E) with IN-SUR-E alone in spontaneously breathing preterm infants requiring nasal continuous positive airway pressure (nCPAP) as initial respiratory support and reaching pre-defined CPAP failure criteria. METHODS/DESIGN: In this study, 206 spontaneously breathing infants born at 24(+0)-27(+6) weeks' gestation and failing nCPAP during the first 24 h of life, will be randomized to receive an HFOV recruitment maneuver (IN-REC-SUR-E) or no recruitment maneuver (IN-SUR-E) just prior to surfactant administration followed by prompt extubation. The primary outcome is the need for mechanical ventilation within the first 3 days of life. Infants in both groups will be considered to have reached the primary outcome when they are not extubated within 30 min after surfactant administration or when they meet the nCPAP failure criteria after extubation. DISCUSSION: From all available data no definitive evidence exists about a positive effect of recruitment before surfactant instillation, but a rationale exists for testing the following hypothesis: a lung recruitment maneuver performed with a step-by-step Continuous Distending Pressure increase during High-Frequency Oscillatory Ventilation (and not with a sustained inflation) could have a positive effects in terms of improved surfactant distribution and consequent its major efficacy in preterm newborns with respiratory distress syndrome. This represents our challenge. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02482766 . Registered on 1 June 2015.


Assuntos
Extubação/métodos , Produtos Biológicos/administração & dosagem , Ventilação de Alta Frequência/métodos , Recém-Nascido Prematuro , Intubação Intratraqueal/métodos , Fosfolipídeos/administração & dosagem , Surfactantes Pulmonares/administração & dosagem , Síndrome do Desconforto Respiratório do Recém-Nascido/terapia , Cafeína/administração & dosagem , Estimulantes do Sistema Nervoso Central/administração & dosagem , Citratos/administração & dosagem , Pressão Positiva Contínua nas Vias Aéreas , Feminino , Humanos , Recém-Nascido , Masculino , Fatores de Tempo , Resultado do Tratamento
5.
Thyroid ; 17(7): 677-80, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17696839

RESUMO

OBJECTIVE: Hereditary (familial) nonautoimmune hyperthyroidism (FNAH) is caused by activating thyroid-stimulating hormone (thyrotropin) receptor (TSHR) germline mutations. We describe a family with recurrent thyrotoxicosis and goiter across three generations, including an 8-year-old girl. MAIN OUTCOME: Sequences of the TSHR gene in the index patient, her father, her paternal grandmother, and a paternal uncle demonstrated the presence of an identical germline TSHR mutation. The mutation was heterozygous and determined the substitution of valine for methionine (codon 463; ATG-->GTG) in the second transmembrane domain of the TSHR in all the affected patients, but in none of the unaffected family members. CONCLUSIONS: We compared the clinical presentation of FNAH in the family reported by us with the other cases harboring the same mutation reported in the literature. This analysis revealed high variability in the phenotypical expression of the disease. In the family reported by us, we also observed a clear anticipation of the onset of the disease across generations, and we discussed whether such a phenomenon can be the consequence of the increased iodine supplementation in the area where the family lives.


Assuntos
Substituição de Aminoácidos , Mutação em Linhagem Germinativa , Hipertireoidismo/genética , Iodo/uso terapêutico , Receptores da Tireotropina/genética , Criança , Suplementos Nutricionais , Feminino , Humanos , Hipertireoidismo/tratamento farmacológico , Iodo/administração & dosagem , Masculino , Linhagem , Polimorfismo de Nucleotídeo Único , Taquicardia/etiologia , Testes de Função Tireóidea , Tremor/etiologia
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