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1.
Sci Rep ; 13(1): 6812, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37100825

RESUMO

An essential part of the world's remaining mineral resources is expected to reside deep in the crust or under post-mineralization cover. For porphyry copper deposits, the world's primary source of Cu, Mo, and Re, identifying the dynamic processes that control their emplacement in the upper crust can guide future exploration. Seismic tomography can constrain these processes through imaging deep-seated structures at the regional scale. Here we construct a three-dimensional model of the Vp/Vs ratio, based on arrival times of P and S seismic waves, beneath the Cerro Colorado porphyry Cu-(Mo) deposit in northern Chile. Our images show that low Vp/Vs (~ 1.55-1.65) anomalies, extending to ~ 5-15 km depth, coincide with the surface expression of known porphyry copper deposits and prospects, as well as delimit structures that host orebodies and related hydrothermal alteration zones. Medium Vp/Vs (~ 1.68-1.74) and high Vp/Vs (Vp/Vs ~ 1.85) bodies correspond to intermediate-felsic plutonic precursors for porphyry intrusions and mafic magma reservoirs that underlie shallower orebodies, respectively. Imaging these precursor and parental plutons is crucial to the identification of orebodies as they act as the source of fluids for porphyry copper generation. This study demonstrates the potential of local earthquake tomography as a tool to identify future deep mineral resources with minimal environmental impact.

2.
Medicina (Kaunas) ; 58(3)2022 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-35334575

RESUMO

Background and objectives: Pre-existing atrial fibrillation (AF) is a frequent comorbidity in hospitalized patients with COVID-19; however, little is still known about its prognostic role in infected patients. The aim of our study was to evaluate whether the pre-existing AF as comorbidity would contribute to increase the risk for severe forms of COVID-19, worse prognosis, or even higher mortality. Materials and Methods: We retrospectively evaluated all consecutive COVID-19 patients admitted to the emergency department of nine Italian Hospitals from 1 March to 30 April 2020.The prevalence and the type of pre-existing AF have been collected. The correlation between the history and type of AF and the development of severe ARDS and in-hospital mortality has been evaluated. Results: In total, 467 patients (66.88 ± 14.55 years; 63% males) with COVID-19 were included in the present study. The history of AF was noticed in 122 cases (26.1%), of which 12 (2.6%) with paroxysmal, 57 (12.2%) with persistent and 53 (11.3%) with permanent AF. Among our study population, COVID-19 patients with AF history were older compared to those without AF history (71.25 ± 12.39 vs. 65.34 ± 14.95 years; p < 0.001); however, they did not show a statistically significant difference in cardiovascular comorbidities or treatments. Pre-existing AF resulted in being independently associated with an increased risk of developing severe ARDS during the hospitalization; in contrast, it did not increase the risk of in-hospital mortality. Among patients with AF history, no significant differences were detected in severe ARDS and in-hospital mortality between patients with permanent and non-permanent AF history. Conclusions: Pre-existing AF is a frequent among COVID-19 patients admitted to hospital, accounting up to 25% of cases. It is independently associated with an increased risk of severe ARDS in hospitalized COVID-19 patients; in contrast, it did not affect the risk of death. The type of pre-existing AF (permanent or non-permanent) did not impact the clinical outcome.


Assuntos
Fibrilação Atrial , COVID-19 , Fibrilação Atrial/complicações , Fibrilação Atrial/epidemiologia , COVID-19/complicações , Feminino , Humanos , Masculino , Prognóstico , Estudos Retrospectivos , Fatores de Risco
3.
Sci Rep ; 11(1): 18424, 2021 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-34531472

RESUMO

Magnetite is the main constituent of iron oxide-apatite (IOA) deposits, which are a globally important source of Fe and other elements such as P and REE, critical for modern technologies. Geochemical studies of magnetite from IOA deposits have provided key insights into the ore-forming processes and source of mineralizing fluids. However, to date, only qualitative estimations have been obtained for one of the key controlling physico-chemical parameters, i.e., the temperature of magnetite formation. Here we reconstruct the thermal evolution of Andean IOA deposits by using magnetite thermometry. Our study comprised a > 3000 point geochemical dataset of magnetite from several IOA deposits within the Early Cretaceous Chilean Iron Belt, as well as from the Pliocene El Laco IOA deposit in the Chilean Altiplano. Thermometry data reveal that the deposits formed under a wide range of temperatures, from purely magmatic (~ 1000 to 800 °C), to late magmatic or magmatic-hydrothermal (~ 800 to 600 °C), to purely hydrothermal (< 600 °C) conditions. Magnetite cooling trends are consistent with genetic models invoking a combined igneous and magmatic-hydrothermal origin that involve Fe-rich fluids sourced from intermediate silicate magmas. The data demonstrate the potential of magnetite thermometry to better constrain the thermal evolution of IOA systems worldwide, and help refine the geological models used to find new resources.

4.
Expert Rev Clin Pharmacol ; 14(10): 1289-1294, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34402362

RESUMO

PURPOSE: We aimed to investigate the clinical performance of edoxaban for the treatment of pulmonary embolism (PE) in hospitalized COVID-19 patients. METHODS: We conducted a retrospective analysis selecting hospitalized patients with COVID-19 admitted to our Institution from 20 May 2020 to 20 November 2020 with computer tomography (CT) detected PE at admission, treated with edoxaban after initial parenteral therapy. Clinical outcomes were compared between patients with and without ARDS at admission and between those with and without CT confirmed PE resolution. RESULTS: 50 patients were included. Mean follow-up was 42.5 ± 10 days. No baseline differences were found between patients with ARDS (30%) and those without ARDS at admission. Patients with PE resolution (84%) were younger (P = 0.03), had a shorter duration of fondaparinux therapy (9.9 ± 3.8 vs 15.8 ± 7.5 days; P = 0.0015) and length of hospitalization (36 ± 8 vs 46 ± 9 days: P = 0.0023) compared with those without PE resolution. 2 patients experienced major bleedings. At multivariate analysis the time to edoxaban switch was the only predictor of the PE resolution (HR: 0.92; 95% C.I. 0.86 to 0.99). CONCLUSION: Edoxaban was an effective and safe treatment for acute PE in COVID-19 setting.


Assuntos
COVID-19/complicações , Inibidores do Fator Xa/uso terapêutico , Embolia Pulmonar/tratamento farmacológico , Piridinas/uso terapêutico , SARS-CoV-2 , Tiazóis/uso terapêutico , Adulto , Idoso , Feminino , Fondaparinux/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Modelos de Riscos Proporcionais , Embolia Pulmonar/etiologia , Síndrome do Desconforto Respiratório , Estudos Retrospectivos
5.
Nutr Metab Cardiovasc Dis ; 30(11): 1899-1913, 2020 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-32912793

RESUMO

BACKGROUND AND AIMS: There is poor knowledge on characteristics, comorbidities and laboratory measures associated with risk for adverse outcomes and in-hospital mortality in European Countries. We aimed at identifying baseline characteristics predisposing COVID-19 patients to in-hospital death. METHODS AND RESULTS: Retrospective observational study on 3894 patients with SARS-CoV-2 infection hospitalized from February 19th to May 23rd, 2020 and recruited in 30 clinical centres distributed throughout Italy. Machine learning (random forest)-based and Cox survival analysis. 61.7% of participants were men (median age 67 years), followed up for a median of 13 days. In-hospital mortality exhibited a geographical gradient, Northern Italian regions featuring more than twofold higher death rates as compared to Central/Southern areas (15.6% vs 6.4%, respectively). Machine learning analysis revealed that the most important features in death classification were impaired renal function, elevated C reactive protein and advanced age. These findings were confirmed by multivariable Cox survival analysis (hazard ratio (HR): 8.2; 95% confidence interval (CI) 4.6-14.7 for age ≥85 vs 18-44 y); HR = 4.7; 2.9-7.7 for estimated glomerular filtration rate levels <15 vs ≥ 90 mL/min/1.73 m2; HR = 2.3; 1.5-3.6 for C-reactive protein levels ≥10 vs ≤ 3 mg/L). No relation was found with obesity, tobacco use, cardiovascular disease and related-comorbidities. The associations between these variables and mortality were substantially homogenous across all sub-groups analyses. CONCLUSIONS: Impaired renal function, elevated C-reactive protein and advanced age were major predictors of in-hospital death in a large cohort of unselected patients with COVID-19, admitted to 30 different clinical centres all over Italy.


Assuntos
Betacoronavirus , Doenças Cardiovasculares/etiologia , Infecções por Coronavirus/mortalidade , Mortalidade Hospitalar , Aprendizado de Máquina , Pneumonia Viral/mortalidade , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Proteína C-Reativa/análise , COVID-19 , Feminino , Taxa de Filtração Glomerular , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Estudos Retrospectivos , Fatores de Risco , SARS-CoV-2 , Análise de Sobrevida , Adulto Jovem
6.
J Cardiovasc Med (Hagerstown) ; 11(7): 507-10, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20407387

RESUMO

Pheochromocytoma is a rare tumor that produces a distant effect by secretion of catecholamines. This tumor usually presents with hypertension and palpitations but it may also cause cardiogenic shock because of catecholamine-induced myocardial dysfunction. We describe a rare case of Takotsubo-like cardiomyopathy as first manifestation of pheochromocytoma with an unusual onset characterized by severe hypotension and transient basal left ventricular ballooning ('inverted' Takotsubo-like cardiomyopathy).


Assuntos
Neoplasias das Glândulas Suprarrenais/diagnóstico , Feocromocitoma/diagnóstico , Choque Cardiogênico/etiologia , Cardiomiopatia de Takotsubo/etiologia , Neoplasias das Glândulas Suprarrenais/complicações , Neoplasias das Glândulas Suprarrenais/cirurgia , Neoplasias das Glândulas Suprarrenais/urina , Adrenalectomia , Adulto , Biomarcadores/urina , Cardiotônicos/uso terapêutico , Catecolaminas/urina , Ecocardiografia , Eletrocardiografia , Feminino , Humanos , Hipotensão/etiologia , Feocromocitoma/complicações , Feocromocitoma/cirurgia , Feocromocitoma/urina , Choque Cardiogênico/diagnóstico , Choque Cardiogênico/tratamento farmacológico , Choque Cardiogênico/urina , Cardiomiopatia de Takotsubo/diagnóstico , Cardiomiopatia de Takotsubo/tratamento farmacológico , Cardiomiopatia de Takotsubo/urina , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Regulação para Cima
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