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1.
Org Biomol Chem ; 22(14): 2739-2743, 2024 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-38497223

RESUMO

This article describes the synthesis and photophysical properties of Aggregation-Induced Emission (enhancement) luminogens derivated from CinNaphts dyes. These fluorophores can be obtained in good yields in a single SNAr step of a fluorinated CinNapht derivative by incorporating hindered aromatic amines. They exhibit AIE(E) behavior associated with solid-state fluorescence covering an emission range from 563 to 722 nm. One carbazole derivative demonstrates a remarkable efficiency in imaging lipid droplets in living cells through an original photophysical mechanism.


Assuntos
Gotículas Lipídicas , Imagem Óptica , Imagem Óptica/métodos , Corantes Fluorescentes
2.
Angew Chem Int Ed Engl ; 63(16): e202317728, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38376889

RESUMO

Applying a single molecular probe to monitor enzymatic activities in multiple, complementary imaging modalities is highly desirable to ascertain detection and to avoid the complexity associated with the use of agents of different chemical entities. We demonstrate here the versatility of lanthanide (Ln3+) complexes with respect to their optical and magnetic properties and their potential for enzymatic detection in NIR luminescence, CEST and T1 MR imaging, controlled by the nature of the Ln3+ ion, while using a unique chelator. Based on X-ray structural, photophysical, and solution NMR investigations of a family of Ln3+ DO3A-pyridine model complexes, we could rationalize the luminescence (Eu3+, Yb3+), CEST (Yb3+) and relaxation (Gd3+) properties and their variations between carbamate and amine derivatives. This allowed the design of L n L G a l 5 ${{{\bf L n L}}_{{\bf G a l}}^{5}}$ probes which undergo enzyme-mediated changes detectable in NIR luminescence, CEST and T1-weighted MRI, respectively governed by variations in their absorption energy, in their exchanging proton pool and in their size, thus relaxation efficacy. We demonstrate that these properties can be exploited for the visualization of ß-galactosidase activity in phantom samples by different imaging modalities: NIR optical imaging, CEST and T1-weighted MRI.


Assuntos
Elementos da Série dos Lantanídeos , Elementos da Série dos Lantanídeos/química , Luminescência , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Quelantes
3.
Anal Chem ; 96(4): 1774-1780, 2024 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-38230524

RESUMO

In this paper, we demonstrate the existence of an endogenous mitochondrial azoreductase (AzoR) activity that can induce the cleavage of N═N double bonds of azobenzene compounds under normoxic conditions. To this end, 100% OFF-ON azo-based fluorogenic probes derived from 4-amino-1,8-naphthalimide fluorophores were synthesized and evaluated. The in vitro study conducted with other endogenous reducing agents of the cell, including reductases, demonstrated both the efficacy and the selectivity of the probe for AzoR. Confocal experiments with the probe revealed an AzoR activity in the mitochondria of living cells under normal oxygenation conditions, and we were able to demonstrate that this endogenous AzoR activity appears to be expressed at different levels across different cell lines. This discovery provides crucial information for our understanding of the biochemical processes occurring within the mitochondria. It thus contributes to a better understanding of its function, which is implicated in numerous pathologies.


Assuntos
Combinação Besilato de Anlodipino e Olmesartana Medoxomila , Naftalimidas , Nitrorredutases , NADH NADPH Oxirredutases/metabolismo , Corantes Fluorescentes/química
4.
Europace ; 25(10)2023 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-37801642

RESUMO

AIMS: Since the introduction of direct oral anticoagulant (DOAC) for atrial fibrillation (AF) therapy, inappropriate and/or underdosing of these drugs has been a major clinical challenge. We evaluated the characteristics of patients with AF treated with inappropriate and low-dose DOACs. METHODS AND RESULTS: Patients with AF treated with inappropriate and low-dose DOACs from October 2021 to December 2021 were evaluated from the French National Prospective Registry (PAFF). We evaluated 1890 patients with AF receiving DOACs (apixaban 55%, dabigatran 7%, and rivaroxaban 38%). Inappropriate dosing was noted in 18% of the population. Patients with appropriate dosing had less comorbidities: younger age (75 ± 10 vs. 82 ± 8 years old, P < 0.0001), reduced chronic renal failure (26 vs. 61%, P < 0.0001), and lower CHA2DS2VASc and HASBLED scores (3 ± 2 vs. 4 ± 3, P < 0.0001; 2 ±1 vs. 2 ± 2, P < 0.0001), respectively. In multivariate analysis, older age (P < 0.0001) and a higher CHA2DS2VASc score (P = 0.0056) were independently associated with inappropriate DOAC dosing. Among 472 patients (27%) treated with low-dose rivaroxaban or apixaban, 46% were inappropriately underdosed. Patients inappropriately underdosed were younger (82.3 ± 8.4 vs. 85.9 ± 5.9 years, P < 0.0001) with less chronic renal disease (47 vs. 98%, P < 0.0001). However, these patients had higher rates of prior haemorrhagic events (18 vs. 10%, P = 0.01), clopidogrel use (11 vs. 3%, P = 0.0002), and apixaban prescription (74 vs. 50%, P < 0.0001). CONCLUSION: Within this large registry, DOACs were associated with inappropriate dosing in 18% of cases. Independent predictors of inappropriate dosing were high CHA2DS2VASc scores and older age. Moreover, 46% of patients treated with low-dose DOACs were inappropriately underdosed and more frequently in patients treated with apixaban.


Assuntos
Fibrilação Atrial , Falência Renal Crônica , Acidente Vascular Cerebral , Humanos , Idoso , Idoso de 80 Anos ou mais , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/complicações , Rivaroxabana , Anticoagulantes , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle , Estudos Retrospectivos , Dabigatrana , Sistema de Registros , Falência Renal Crônica/complicações , Administração Oral
5.
Pediatr Radiol ; 53(12): 2446-2457, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37773445

RESUMO

BACKGROUND: Hepatic hemangiomas may be associated with serious complications; however, it is unknown whether ultrasound (US) features can predict complications. OBJECTIVE: To analyze initial US features of hepatic hemangiomas predictive of complications. MATERIALS AND METHODS: This is a single-center retrospective cohort study of clinical, biological, and imaging data of infants with hepatic hemangioma between 2000 and 2018. Patients were categorized as having or not having any complication(s). Associations between initial US features and complications were analyzed through logistic regression. Receiver operating characteristic (ROC) curve analyses were performed to determine optimal cutoff values for continuous variables. Stepwise forward logistic regression was used to construct risk prediction models with training and validation sets. Model calibration and discrimination were evaluated using Hosmer-Lemeshow tests, area under the ROC curve, and overall accuracy. RESULTS: Of 112 infants with hepatic hemangioma, 67 (60%) had focal, 32 (28%) had multifocal, and 13 (12%) had diffuse lesions, with complication rates of 51%, 34%, and 92%, respectively, mostly cardiac (54/57, 95%). The US characteristics of the hemangiomas were diverse. Risk factors for complications included diffuse subtype; large tumor volume (focal forms); elevated peak systolic hepatic arterial velocity (PSV); and hepatic vein dilation. For focal forms, initial tumor volume >40 ml and PSV >100 cm/s had >70% sensitivity and specificity, respectively, to predict complications; a model including these variables had 75% overall accuracy in the validation set. For multifocal/diffuse forms, a PSV >115 cm/s had sensitivity and specificity to predict complications of >70%; a model including this variable had 78% overall accuracy in the validation set. CONCLUSION: Diffuse subtype, large tumor volume, elevated hepatic arterial PSV, and hepatic vein dilation are risk factors for complications of hepatic hemangiomas.


Assuntos
Hemangioma , Neoplasias Hepáticas , Doenças Vasculares , Lactente , Humanos , Criança , Prognóstico , Estudos Retrospectivos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Hemangioma/diagnóstico por imagem , Sensibilidade e Especificidade
6.
Antioxidants (Basel) ; 12(9)2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37760055

RESUMO

Vitamin E is an essential nutrient usually recommended in post-weaning piglets, when a decline in the serum vitamin E concentration is observed. Selected polyphenols have the potential to partially replace vitamin E in animal feed. The aim of this study was to investigate the effect of the dietary inclusion of some commercial polyphenol products (PPs) on the growth performance, antioxidant status and immunity of post-weaning piglets. A total of 300 piglets (BW 7.18 kg ± 1.18) were randomly assigned to six dietary groups: CON- (40 mg/kg vitamin E); CON+(175.8 mg/kg vitamin E); and PP1, PP2, PP3 and PP4, in which 50% vitamin E of CON+ was replaced with PP with equivalent vitamin E activity. The PP1 group exhibited lower performance (p < 0.05) than the other dietary groups, but a similar performance to that commonly registered in pig farms. Dietary polyphenols did not influence the IgG concentration or the IL-6, IL-10, IFN-γ and TNF-α cytokine concentrations. A lower IL-8 level was found in the PP4 group than in the other groups. The diets that affected the vitamin A content showed the highest value (p < 0.05) in the PP1 group, and a trend was noted for vitamin E with a higher content in PP4 and CON+. The polyphenols-enriched diets, especially the PP3 diet, maintained an antioxidant capacity (whole blood KRL) similar to the CON+ diet. In conclusion, the replacement of vitamin E with all PPs enables partial vitamin E substitution in post-weaning piglets.

7.
J Am Coll Cardiol ; 82(7): 590-599, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37558371

RESUMO

BACKGROUND: Very few data have been published on the use of subcutaneous implantable cardioverter-defibrillators (S-ICDs) in patients with congenital heart disease (CHD). OBJECTIVES: The aim of this study was to analyze outcomes associated with S-ICDs in patients with CHD. METHODS: This nationwide French cohort including all patients with an S-ICD was initiated in 2020 by the French Institute of Health and Medical Research. Characteristics at implantation and outcomes were analyzed in patients with CHD. RESULTS: From October 12, 2012, to December 31, 2019, among 4,924 patients receiving an S-ICD implant in 150 centers, 101 (2.1%) had CHD. Tetralogy of Fallot, univentricular heart, and dextro-transposition of the great arteries represented almost one-half of the population. Patients with CHD were significantly younger (age 37.1 ± 15.4 years vs 50.1 ± 14.9 years; P < 0.001), more frequently female (37.6% vs 23.0%; P < 0.001), more likely to receive an S-ICD for secondary prevention (72.3% vs 35.9%; P < 0.001), and less likely to have severe systolic dysfunction of the systemic ventricle (28.1% vs 53.1%; P < 0.001). Over a mean follow-up period of 1.9 years, 16 (15.8%) patients with CHD received at least 1 appropriate shock, with all shocks successfully terminating the ventricular arrhythmia. The crude risk of appropriate S-ICD shock was twice as high in patients with CHD compared with non-CHD patients (annual incidences of 9.0% vs 4.4%; HR: 2.1; 95% CI: 1.3-3.4); however, this association was no longer significant after propensity matching (especially considering S-ICD indication, P = 0.12). The burden of all complications (HR: 1.2; 95% CI: 0.7-2.1; P = 0.4) and inappropriate shocks (HR: 0.9; 95% CI: 0.4-2.0; P = 0.9) was comparable in both groups. CONCLUSIONS: In this nationwide study, patients with CHD represented 2% of all S-ICD implantations. Our findings emphasize the effectiveness and safety of S-ICD in this particularly high-risk population. (S-ICD French Cohort Study [HONEST]; NCT05302115).


Assuntos
Desfibriladores Implantáveis , Cardiopatias Congênitas , Transposição dos Grandes Vasos , Humanos , Feminino , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Desfibriladores Implantáveis/efeitos adversos , Morte Súbita Cardíaca/epidemiologia , Morte Súbita Cardíaca/prevenção & controle , Morte Súbita Cardíaca/etiologia , Estudos de Coortes , Resultado do Tratamento , Estudos Retrospectivos , Cardiopatias Congênitas/complicações , Cardiopatias Congênitas/terapia
8.
Chem Sci ; 14(22): 6000-6010, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37293654

RESUMO

A simple and easy-to-implement process based on a nucleophilic aromatic substitution reaction with a wide variety of nucleophiles on a fluorinated CinNapht is described. This process has the key advantage of introducing multiple functionalities at a very late stage, thus providing access to new applications including the synthesis of photostable and bioconjugatable large Stokes shift red emitting dyes and selective organelle imaging agents, as well as AIEE-based wash-free lipid droplet imaging in live cells with high signal-to-noise ratio. The synthesis of bench-stable CinNapht-F has been optimized and can be reproduced on a large scale, making it an easy-to-store starting material that can be used at will to prepare new molecular imaging tools.

9.
Blood Purif ; 52(6): 541-548, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37105135

RESUMO

INTRODUCTION: Sepsis is a life-threatening organ dysfunction caused by a dysregulated host response to infection. As such, circulating cytokines and danger- and pathogen-associated molecular patterns (such as endotoxins) are recognized as central in the pathogenesis of sepsis and organ dysfunction. Removing these compounds by extracorporeal blood filtration, commonly considered blood purification, may improve the septic patients' condition. This study aimed to assess the vaso-inotropic support evolution over time in pediatric patients with vasoplegic shock treated with oXiris©. METHODS: All patients aged below 18 years admitted at the Paris Saclay University Quaternary Pediatric Intensive Care Unit with vasoplegic shock and acute kidney injury and treated with oXiris© between October 2017 and January 2020 were included. The vaso-inotropic score and the 28-day mortality were assessed. Improvement under treatment was defined as a 50% decrease in the vaso-inotropic score following 24 h of oXiris© therapy. RESULTS: Eleven pediatric patients aged 2-15 years and weighing 11-60 kg were admitted with vasoplegic shock and acute kidney injury. They received thirteen sessions of oXiris© therapy for septic shock (N = 7) and liver failure (N = 6). Eight patients did not improve their condition during the session, and five ultimately died (37.5% survival). Five patients improved, decreasing their inotropic support by >50% in 24 h. Among them, four survived (80%). CONCLUSION: Hemofiltration and extracorporeal blood purification with oXiris© can be used in pediatric patients with vasoplegic shock with rapid improvement in hemodynamics in selected patients.


Assuntos
Injúria Renal Aguda , Fármacos Cardiovasculares , Sepse , Choque Séptico , Criança , Humanos , Injúria Renal Aguda/terapia , Estado Terminal/terapia , Insuficiência de Múltiplos Órgãos/etiologia , Insuficiência de Múltiplos Órgãos/terapia , Sepse/terapia , Pré-Escolar , Adolescente
10.
Intensive Care Med ; 49(1): 5-25, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36592200

RESUMO

PURPOSE: We present guidelines for the management of infants under 12 months of age with severe bronchiolitis with the aim of creating a series of pragmatic recommendations for a patient subgroup that is poorly individualized in national and international guidelines. METHODS: Twenty-five French-speaking experts, all members of the Groupe Francophone de Réanimation et Urgence Pédiatriques (French-speaking group of paediatric intensive and emergency care; GFRUP) (Algeria, Belgium, Canada, France, Switzerland), collaborated from 2021 to 2022 through teleconferences and face-to-face meetings. The guidelines cover five areas: (1) criteria for admission to a pediatric critical care unit, (2) environment and monitoring, (3) feeding and hydration, (4) ventilatory support and (5) adjuvant therapies. The questions were written in the Patient-Intervention-Comparison-Outcome (PICO) format. An extensive Anglophone and Francophone literature search indexed in the MEDLINE database via PubMed, Web of Science, Cochrane and Embase was performed using pre-established keywords. The texts were analyzed and classified according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology. When this method did not apply, an expert opinion was given. Each of these recommendations was voted on by all the experts according to the Delphi methodology. RESULTS: This group proposes 40 recommendations. The GRADE methodology could be applied for 17 of them (3 strong, 14 conditional) and an expert opinion was given for the remaining 23. All received strong approval during the first round of voting. CONCLUSION: These guidelines cover the different aspects in the management of severe bronchiolitis in infants admitted to pediatric critical care units. Compared to the different ways to manage patients with severe bronchiolitis described in the literature, our original work proposes an overall less invasive approach in terms of monitoring and treatment.


Assuntos
Bronquiolite , Ventilação não Invasiva , Humanos , Lactente , Criança , Unidades de Terapia Intensiva Pediátrica , Bronquiolite/diagnóstico , Bronquiolite/terapia , Hospitalização , Ventilação não Invasiva/métodos , Cuidados Críticos
11.
J Oleo Sci ; 71(8): 1117-1133, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35922928

RESUMO

The present study provides the fatty acid, tocopherol, phytosterol, and polyphenol profiles of some Mediterranean oils extracted from pumpkin, melon, and black cumin seed oils and those of dietary argan seed oil. Gas chromatography analysis revealed that oleic and linoleic acids were the most abundant fatty acids. Argan and melon seed oils exhibited the highest levels of oleic acid (47.32±0.02%) and linoleic acid (58.35±0.26%), respectively. In terms of tocopherols, melon seed oil showed the highest amount (652.1±3.26 mg/kg) with a predominance of γ-tocopherol (633.1±18.81 mg/kg). The phytosterol content varied between 2237.00±37.55 µg/g for argan oil to 6995.55±224.01 µg/g for melon seed oil. High Performance Liquid Chromatography analysis also revealed the presence of several polyphenols: vanillin (0.59 mg equivalents Quercetin/100 g) for melon seed oil, and p-hydroxycinnamic acid (0.04 mg equivalents Quercetin/100 g), coumarine (0.05 mg equivalents Quercetin/100 g), and thymoquinone (1.2 mg equivalents Quercetin/100 g) for black cumin seed oil. The "Kit Radicaux Libres" (KRL) assay used to evaluate the scavenging properties of the oils showed that black cumin seed oil was the most efficient. On the light of the richness of all Mediterranean oil samples in bioactive compounds, the seed oils studied can be considered as important sources of nutrients endowed with cytoprotective properties which benefits in preventing age-related diseases which are characterized by an enhanced oxidative stress.


Assuntos
Fitosteróis , Tocoferóis , Ácidos Graxos/análise , Nutrientes/análise , Óleos de Plantas/química , Polifenóis/análise , Quercetina , Esteróis/análise , Tocoferóis/análise
12.
Molecules ; 27(15)2022 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-35897887

RESUMO

Trans-resveratrol is a natural polyphenol showing numerous biological properties, especially anti-tumoral and antioxidant activity. Among numerous resveratrol derivatives, aza-stilbenes, which bear an imine bound, show interesting biological activities. In the present study, we synthesized a series of imine analogs of trans-resveratrol (seven aza-stilbenes) following an easy and low-cost procedure of green chemistry. The toxicity of synthesized aza-stilbenes, which is currently unknown, was evaluated on murine neuronal N2a cells, comparatively to trans-resveratrol, by considering: cell density evaluated by staining with sulforhodamine 101; esterase activity, which is a criteria of cell viability, by staining with fluorescein diacetate; and transmembrane mitochondrial potential, which is known to decrease during cell death, by staining with DiOC6(3) using flow cytometry. In addition, the antioxidant activity was quantified with the KRL (Kit Radicaux Libres) assay, the DPPH (2,2'-diphenyl-1-picrylhydrazyl radical) assay and the FRAP (ferric reducing antioxidant power) assay. The PAOT (Pouvoir Antioxidant Total) score was also used. The aza-stilbenes provide different cytotoxic and antioxidant activities, which are either higher or lower than those of trans-resveratrol. Based on their cytotoxic and antioxidant characteristics, all synthesized aza-stilbenes are distinguished from trans-resveratrol.


Assuntos
Antineoplásicos , Estilbenos , Animais , Antineoplásicos/química , Antioxidantes/química , Antioxidantes/farmacologia , Iminas/farmacologia , Camundongos , Resveratrol/farmacologia , Estilbenos/química , Estilbenos/farmacologia
13.
J Invasive Cardiol ; 34(4): E281-E285, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35302947

RESUMO

OBJECTIVES: We aimed to validate whether quantitative flow ratio (QFR) analysis could be performed by both medical and paramedical certified users. Therefore, we compared QFR values with conventional guidewire-based fractional flow reserve (FFR) as the reference using core laboratory analysis. QFR allows FFR calculation based on the coronary angiogram. QFR analysis requires certified users with dedicated training and skills. However, the ability of medical and paramedical users to correctly analyze QFR remains unknown. METHODS: In a prospective, single-center study, we included all consecutive patients with stable coronary artery disease and indicated physiological assessment. QFR was performed and analyzed by 1 medical and 2 paramedical QFR users who were unaware of conventional pressure-guidewire FFR measurements. RESULTS: We included 67 consecutive patients and 100 lesions for assessment with QFR and FFR. Pearson's correlation coefficient of QFR performed by paramedical users compared with medical users was 0.89 (range, 0.83-0.92). A Bland-Altman analysis showed no significant bias (-0.0008). Receiver-operator characteristic curves were generated to compare the ability to predict an FFR value above or below 0.80 with QFR performed by paramedical vs medical users. When comparing FFR with QFR performed by paramedical and medical users, the values for area under the curve were 0.964 and 0.970, respectively. Intraclass correlation was 0.884. CONCLUSION: Our study showed a noticeable correlation between QFR analysis performed by QFR-certified paramedical and medical users, as compared with FFR. These data suggest that QFR analysis could be performed by certified paramedicals in order to reduce physician workload without impacting the quality of the obtained results.


Assuntos
Doença da Artéria Coronariana , Estenose Coronária , Reserva Fracionada de Fluxo Miocárdico , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico , Vasos Coronários , Reserva Fracionada de Fluxo Miocárdico/fisiologia , Humanos , Valor Preditivo dos Testes , Estudos Prospectivos , Reprodutibilidade dos Testes , Índice de Gravidade de Doença
14.
Bioconjug Chem ; 33(1): 180-193, 2022 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-34986302

RESUMO

Targeted contrast agents (CAs) can improve magnetic resonance imaging (MRI) for accurate cancer diagnosis. In this work, we used the Shiga toxin B-subunit (STxB) as a targeting agent, which binds to Gb3, a glycosphingolipid highly overexpressed on the surface of tumor cells. We developed STxB-targeted MRI probes from cyclic peptide scaffolds functionalized with six to nine monoamide DO3A[Gd(III)] chelates. The influence of structural constraints on the longitudinal relaxivity (r1) of the CAs has been studied. The cyclic peptide carrying nine monoamide DO3A[Gd(III)] exhibited a r1 per compound of 32 and 93 mM-1s-1 at 9.4 and 1.5 T, respectively. Its conjugation to the pentameric STxB protein led to a 70 kDa compound with a higher r1 of 150 and 475 mM-1 s-1 at 9.4 and 1.5 T, respectively. Specific accumulation and cellular distribution of this conjugate in Gb3-expressing cancer cells were demonstrated using immunofluorescence microscopy and quantified by an inductively coupled plasma-mass spectrometry dosage of Gd(III). Such an agent should enable the in vivo detection by MRI of tumors expressing Gb3 receptors.


Assuntos
Meios de Contraste
15.
Int J Mol Sci ; 24(1)2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36614009

RESUMO

The interaction between Respiratory Syncytial Virus phosphoprotein P and nucleoprotein N is essential for the formation of the holo RSV polymerase that carries out replication. In vitro screening of antivirals targeting the N-P protein interaction requires a molecular interaction model, ideally consisting of a complex between N protein and a short peptide corresponding to the C-terminal tail of the P protein. However, the flexibility of C-terminal P peptides as well as their phosphorylation status play a role in binding and may bias the outcome of an inhibition assay. We therefore investigated binding affinities and dynamics of this interaction by testing two N protein constructs and P peptides of different lengths and composition, using nuclear magnetic resonance and fluorescence polarization (FP). We show that, although the last C-terminal Phe241 residue is the main determinant for anchoring P to N, only longer peptides afford sub-micromolar affinity, despite increasing mobility towards the N-terminus. We investigated competitive binding by peptides and small compounds, including molecules used as fluorescent labels in FP. Based on these results, we draw optimized parameters for a robust RSV N-P inhibition assay and validated this assay with the M76 molecule, which displays antiviral properties, for further screening of chemical libraries.


Assuntos
Nucleoproteínas , Vírus Sincicial Respiratório Humano , Vírus Sincicial Respiratório Humano/metabolismo , Peptídeos/metabolismo , Fosfoproteínas/metabolismo , Polarização de Fluorescência
16.
Proc Natl Acad Sci U S A ; 118(50)2021 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-34873034

RESUMO

Hydrogen peroxide (H2O2) is responsible for numerous damages when overproduced, and its detection is crucial for a better understanding of H2O2-mediated signaling in physiological and pathological processes. For this purpose, various "off-on" small fluorescent probes relying on a boronate trigger have been prepared, and this design has also been involved in the development of H2O2-activated prodrugs or theranostic tools. However, this design suffers from slow kinetics, preventing activation by H2O2 with a short response time. Therefore, faster H2O2-reactive groups are awaited. To address this issue, we have successfully developed and characterized a prototypic borinic-based fluorescent probe containing a coumarin scaffold. We determined its in vitro kinetic constants toward H2O2-promoted oxidation. We measured 1.9 × 104 m-1⋅s-1 as a second-order rate constant, which is 10,000-fold faster than its well-established boronic counterpart (1.8 m-1⋅s-1). This improved reactivity was also effective in a cellular context, rendering borinic acids an advantageous trigger for H2O2-mediated release of effectors such as fluorescent moieties.

17.
Ann Intensive Care ; 11(1): 111, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34259942

RESUMO

BACKGROUND: De-regulated host response to severe coronavirus disease 2019 (COVID-19), directly referring to the concept of sepsis-associated immunological dysregulation, seems to be a strong signature of severe COVID-19. Myeloid cells phenotyping is well recognized to diagnose critical illness-induced immunodepression in sepsis and has not been well characterized in COVID-19. The aim of this study is to review phenotypic characteristics of myeloid cells and evaluate their relations with the occurrence of secondary infection and mortality in patients with COVID-19 admitted in an intensive care unit. METHODS: Retrospective analysis of the circulating myeloid cells phenotypes of adult COVID-19 critically ill patients. Phenotyping circulating immune cells was performed by flow cytometry daily for routine analysis and twice weekly for lymphocytes and monocytes subpopulations analysis, as well as monocyte human leukocyte antigen (mHLA)-DR expression. RESULTS: Out of the 29 critically ill adult patients with severe COVID-19 analyzed, 12 (41.4%) developed secondary infection and six patients died during their stay. Monocyte HLA-DR kinetics was significantly different between patients developing secondary infection and those without, respectively, at day 5-7 and 8-10 following admission. The monocytes myeloid-derived suppressor cells to total monocytes ratio was associated with 28- and 60-day mortality. Those myeloid characteristics suggest three phenotypes: hyperactivated monocyte/macrophage is significantly associated with mortality, whereas persistent immunodepression is associated with secondary infection occurrence compared to transient immunodepression. CONCLUSIONS: Myeloid phenotypes of critically ill COVID-19 patients may be associated with development of secondary infection, 28- and 60-day mortality.

18.
Environ Sci Pollut Res Int ; 28(21): 26606-26616, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33495953

RESUMO

Many toxicants are present in water as a mixture. Male infertility is one of the environmental impacts in developed countries. Using our rat seminiferous tubule culture model, we evaluated the effects of waters of different origins, on several parameters of the seminiferous epithelium. Concentrated culture medium was diluted with the waters to be tested (final concentrations of the tested waters were between 8 and 80%). The integrity of the blood-testis barrier was assessed by the trans-epithelial electric resistance (TEER). The levels of mRNAs specific of Sertoli cells, of cellular junctions, of each population of germ cells, of androgen receptor, of estrogen receptor α, and of aromatase were also studied. We report, here, the results obtained with ten waters, some of them possessing a negative effect on spermatogenesis. The results showed that, according to the tested waters, their effects on the parameters studied might be quite different indicating many different mechanisms of toxicity, including some endocrine-disrupting effects. It has been reported that men with impaired semen parameters have an increased mortality rate suggesting semen quality may provide a fundamental biomarker of overall male health. Hence, we have developed a relevant in vitro bioassay allowing the evaluation of the potential toxicity of different types of waters on male fertility and to assess some aspects of their mechanism of action. In addition to the TEER measure, the number and/or the identity of the studied mRNAs can be largely increased and/or modified, thus enhancing the possibility of using this model as a "warning system."


Assuntos
Análise do Sêmen , Espermatogênese , Animais , Bioensaio , Barreira Hematotesticular , Humanos , Masculino , Projetos Piloto , Ratos , Células de Sertoli , Testículo
19.
RSC Adv ; 11(48): 30088-30092, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-35493990

RESUMO

Six-membered-diaza ring of cinnoline has been fused on naphthalimide dye to give a donor-acceptor system called CinNapht. This red shifted fluorophore, that can be synthesised in gram scale, exhibits a large Stoke shift and a fluorescence quantum yield up to 0.33. It is also characterized by a strong solvatochromic effect from green to red emission as well and can be used for bio-imaging.

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