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1.
Adv Mater ; : e2403885, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38739417

RESUMO

Low-melting liquid metals are emerging as a new group of highly functional solvents due to their capability to dissolve and alloy various metals in their elemental state to form solutions as well as colloidal systems. Furthermore, these liquid metals can facilitate and catalyze multiple unique chemical reactions. Despite the intriguing science behind liquid metals and alloys, very little is known about their fundamental structures in the nanometric regime. To bridge this gap, this work employs small angle neutron scattering and molecular dynamics simulations, revealing that the most commonly used liquid metal solvents, EGaIn and Galinstan, are surprisingly structured with the formation of clusters ranging from 157 to 15.7 Å. Conversely, noneutectic liquid metal alloys of GaSn or GaIn at low solute concentrations of 1, 2, and 5 wt%, as well as pure Ga, do not exhibit these structures. Importantly, the eutectic alloys retain their structure even at elevated temperatures of 60 and 90 °C, highlighting that they are not just simple homogeneous fluids consisting of individual atoms. Understanding the complex soft structure of liquid alloys will assist in comprehending complex phenomena occurring within these fluids and contribute to deriving reaction mechanisms in the realm of synthesis and liquid metal-based catalysis.

2.
Adv Sci (Weinh) ; : e2400147, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38704677

RESUMO

Crystallization of alloys from a molten state is a fundamental process underpinning metallurgy. Here the direct imaging of an intermetallic precipitation reaction at equilibrium in a liquid-metal environment is demonstrated. It is shown that the outer layers of a solidified intermetallic are surprisingly unstable to the depths of several nanometers, fluctuating between a crystalline and a liquid state. This effect, referred to herein as crystal interface liquefaction, is observed at remarkably low temperatures and results in highly unstable crystal interfaces at temperatures exceeding 200 K below the bulk melting point of the solid. In general, any liquefaction process would occur at or close to the formal melting point of a solid, thus differentiating the observed liquefaction phenomenon from other processes such as surface pre-melting or conventional bulk melting. Crystal interface liquefaction is observed in a variety of binary alloy systems and as such, the findings may impact the understanding of crystallization and solidification processes in metallic systems and alloys more generally.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38548169

RESUMO

BACKGROUND: Asthmatic patients with antibody deficiencies (AD) have more severe disease and higher risk of exacerbations. No data exist about the efficacy of biologics in severe asthma (SA) patients with AD. OBJECTIVE: To evaluate the efficacy of biologics in SA patients with and without AD. METHODS: A case-control real-life study was conducted including 68 patients divided into 2 groups: group 1 with SA-AD and group 2 with SA. RESULTS: Treatment with biologics for 6 months was effective for decreasing the number of exacerbations, hospitalizations, and emergency department (ED) visits and improving the Asthma Control Questionnaire (ACQ) score; biologics also proved a systemic corticosteroid-sparing effect. Despite benefits, the number of exacerbations, hospitalizations, and ED visits, the mean ACQ score, and the cumulative dose of systemic corticosteroids remain higher in group 1 than in group 2, with lower lung function parameters. The rates of responses in group 1 were inferior to those in group 2, with a decrease by ≥50% of exacerbation rate in 76% versus 97% of patients (P = .006), no hospitalization in 44% versus 91% of patients (P < .001), no ED visit in 56% versus 82% of patients (P = .018), a significant improvement of the ACQ score by ≥0.5 in 68% versus 100% of patients (P < .001), and an increase of forced expiratory volume in the first second by >10% in 32% versus 65% of patients (P = .007). CONCLUSIONS: Despite evident benefits, SA patients with AD have suboptimal responses to biologics compared with those immunocompetent. A multidisciplinary approach is necessary to optimize the management of these patients in practice.

4.
Neurochirurgie ; 69(6): 101497, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37757629

RESUMO

Ectopic thyroid is well-known pathology for several decades. Many locations have been described. Nowadays, only three cases of skull base location have been described in literature. In our case, we reported a single case of a 39-year-old male presenting with a supra-sellar and suprachiasmatic location. He presented no clinical symptoms, no endocrine alteration on biology and no skull base invasion which make this case unique compared to actual literature. Such diagnosis should always be an exclusion diagnosis as secondary neoplastic should be first ruled out.


Assuntos
Disgenesia da Tireoide , Masculino , Humanos , Adulto , Disgenesia da Tireoide/diagnóstico , Disgenesia da Tireoide/cirurgia , Crânio
5.
J Clin Med ; 12(9)2023 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-37176590

RESUMO

OBJECTIVES: Extrapulmonary tuberculosis (EPTB) can be difficult to diagnose, especially in severe forms. The Xpert MTB/RIF Ultra test introduced an additional category called trace to reference very small amounts of Mycobacterium tuberculosis complex (MTBC) DNA. The objective of our multicenter study was to evaluate whether the trace result on an extrapulmonary (EP) sample is a sufficient argument to consider diagnosing tuberculosis and starting treatment, even in severe cases. METHODS: A retrospective, multicenter cohort study was conducted from 2018 to 2022. Patients strongly suspected of EPTB with a trace result on an EP specimen were included. Hospital records were reviewed for clinical, treatment, and paraclinical data. RESULTS: A total of 52 patients were included, with a severe form in 22/52 (42.3%) cases. Culture was positive for MTBC in 33/46 (71.7%) cases. Histological analysis showed granulomas in 36/45 (80.0%) cases. An Ultra trace result with a presumptive diagnosis of TB led to the decision to treat 41/52 (78.8%) patients. All patients were started on first-line anti-TB therapy (median duration of 6.1 months), with a favorable outcome in 31/35 (88.6%) patients. The presence of a small amount of MTBC genome in EPTB is a sufficient argument to treat patients across a large region of France.

9.
Bull Cancer ; 106(5): 421-430, 2019 May.
Artigo em Francês | MEDLINE | ID: mdl-30981465

RESUMO

INTRODUCTION: The results from the medical literature regarding the influence of patient's age on the delay of treatment in lung cancer are controversial in the absence of a consensual definition. The aim of this study was to determine the impact of the patient's age on the delay of the lung cancer treatment. METHODS: A retrospective monocentric study was performed including patients treated for a lung cancer in our department between November 1, 2014 and October 31, 2015. The delay of treatment was defined by the delay between the first abnormal imaging and the first treatment. The patients were divided into three groups depending on their age: group 1 with≤60 years old, group 2 between 60 and 70 years old, and group 3 with>70 years old. The statistical analysis was realized with Pearson's chi-squared and the Anova tests. RESULTS: Two-hundred and forty-six patients were included with a mean age at 65±10 years. The mean delay of the treatment was 97±41 days. The mean delay of the treatment in patients with>70 years old was statically longer than the delay of treatment in patients with≤60 years old (116±98 days vs. 76±65 days, P=0.04), secondary to an extended time for the lung cancer surgery (129±75 days vs. 88±54 days, P=0.03). CONCLUSION: In patients with>70 years old, the delay of treatment is longer than in other groups, secondary to an extended time for the preoperative assessment. An improvement in therapeutic management is necessary in our care system to shorten this delay.


Assuntos
Neoplasias Pulmonares/terapia , Tempo para o Tratamento , Fatores Etários , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo
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