Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Eur J Endocrinol ; 190(4): 327-337, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38571387

RESUMEN

BACKGROUND: Various glucocorticoid replacement therapies (GRTs) are available for adrenal insufficiency (AI). However, their effectiveness in restoring glucocorticoid rhythm and exposure lacks adequate biochemical markers. We described the diurnal salivary cortisol (SalF) and cortisone (SalE) rhythm among different GRTs and analysed the associations between saliva-derived parameters and life quality questionnaires. METHODS: Control subjects (CSs, n = 28) and AI patients receiving hydrocortisone (HC, n = 9), cortisone acetate (CA, n = 23), and dual-release hydrocortisone once (DRHC-od, n = 10) and twice a day (DRHC-td, n = 6) collected 9 saliva samples from 07:00 to 23:00. Patients compiled Pittsburgh Sleep Quality Index, Hospital Anxiety and Depression Scale, and Addison disease-specific quality-of-life questionnaires. SalE and SalF were measured by liquid chromatography-mass spectrometry. Exposure was monitored using SalE for HC and DRHC and SalF for CA. Area under the curve (AUC) was computed. Different GRTs were compared by Z-scores calculated from saliva-derived parameters. Questionnaire results predictors were evaluated with multiple regression analysis. RESULTS: Compared with controls, all GRTs resulted in glucocorticoid overexposure in the morning. Hydrocortisone, CA, and DRHC-td caused overexposure also in afternoon and evening. Compared with other treatments, CA determined increased Z-score-07:00 (P < .001), DRHC-td determined increased Z-score-AUC07:00→14:00 (P = .007), and DRHC-od induced lower Z-score-AUC14:00→23:00 (P = .015). Z-scores-AUC14:00→16:00 ≥ .619 best predicted questionnaire scores. CONCLUSIONS: None of the GRTs mimics normal glucocorticoid rhythmicity and exposure. SalE, SalF, and Z-score may be useful markers for monitoring and comparing different GRTs. Excess glucocorticoid in early afternoon best associated with depressive symptoms and worse life and sleep quality.


Asunto(s)
Insuficiencia Suprarrenal , Cortisona , Humanos , Glucocorticoides/efectos adversos , Hidrocortisona/análisis , Proyectos Piloto , Insuficiencia Suprarrenal/inducido químicamente , Insuficiencia Suprarrenal/diagnóstico , Insuficiencia Suprarrenal/tratamiento farmacológico , Cortisona/uso terapéutico , Cortisona/análisis , Saliva/química
2.
Nat Mater ; 22(3): 369-379, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36443576

RESUMEN

Messenger RNA has now been used to vaccinate millions of people. However, the diversity of pulmonary pathologies, including infections, genetic disorders, asthma and others, reveals the lung as an important organ to directly target for future RNA therapeutics and preventatives. Here we report the screening of 166 polymeric nanoparticle formulations for functional delivery to the lungs, obtained from a combinatorial synthesis approach combined with a low-dead-volume nose-only inhalation system for mice. We identify P76, a poly-ß-amino-thio-ester polymer, that exhibits increased expression over formulations lacking the thiol component, delivery to different animal species with varying RNA cargos and low toxicity. P76 allows for dose sparing when delivering an mRNA-expressed Cas13a-mediated treatment in a SARS-CoV-2 challenge model, resulting in similar efficacy to a 20-fold higher dose of a neutralizing antibody. Overall, the combinatorial synthesis approach allowed for the discovery of promising polymeric formulations for future RNA pharmaceutical development for the lungs.


Asunto(s)
COVID-19 , Animales , Ratones , ARN Mensajero/genética , SARS-CoV-2/genética , Polímeros/metabolismo , Pulmón , ARN/metabolismo
3.
Adv Sci (Weinh) ; 9(34): e2202771, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36316224

RESUMEN

Despite the success of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) vaccines, there remains a clear need for new classes of preventatives for respiratory viral infections due to vaccine hesitancy, lack of sterilizing immunity, and for at-risk patient populations, including the immunocompromised. While many neutralizing antibodies have been identified, and several approved, to treat COVID-19, systemic delivery, large doses, and high costs have the potential to limit their widespread use, especially in low- and middle-income countries. To use these antibodies more efficiently, an inhalable formulation is developed that allows for the expression of mRNA-encoded, membrane-anchored neutralizing antibodies in the lung to mitigate SARS-CoV-2 infections. First, the ability of mRNA-encoded, membrane-anchored, anti-SARS-CoV-2 antibodies to prevent infections in vitro is demonstrated. Next, it is demonstrated that nebulizer-based delivery of these mRNA-expressed neutralizing antibodies potently abrogates disease in the hamster model. Overall, these results support the use of nebulizer-based mRNA expression of neutralizing antibodies as a new paradigm for mitigating respiratory virus infections.


Asunto(s)
COVID-19 , Humanos , SARS-CoV-2 , ARN Mensajero/genética , Anticuerpos Neutralizantes/uso terapéutico
4.
Nat Biomed Eng ; 5(9): 1059-1068, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34616046

RESUMEN

Lipid nanoparticles (LNPs) for the efficient delivery of drugs need to be designed for the particular administration route and type of drug. Here we report the design of LNPs for the efficient delivery of therapeutic RNAs to the lung via nebulization. We optimized the composition, molar ratios and structure of LNPs made of lipids, neutral or cationic helper lipids and poly(ethylene glycol) (PEG) by evaluating the performance of LNPs belonging to six clusters occupying extremes in chemical space, and then pooling the lead clusters and expanding their diversity. We found that a low (high) molar ratio of PEG improves the performance of LNPs with neutral (cationic) helper lipids, an identified and optimal LNP for low-dose messenger RNA delivery. Nebulized delivery of an mRNA encoding a broadly neutralizing antibody targeting haemagglutinin via the optimized LNP protected mice from a lethal challenge of the H1N1 subtype of influenza A virus, and delivered mRNA more efficiently than LNPs previously optimized for systemic delivery. A cluster approach to LNP design may facilitate the optimization of LNPs for other administration routes and therapeutics.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A , Nanopartículas , Animales , Liposomas , Pulmón , Ratones , ARN Mensajero , ARN Interferente Pequeño
5.
JCI Insight ; 6(23)2021 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-34699383

RESUMEN

Understanding viral rebound in pediatric HIV-1 infection may inform the development of alternatives to lifelong antiretroviral therapy (ART) to achieve viral remission. We thus investigated viral rebound after analytical treatment interruption (ATI) in 10 infant macaques orally infected with SHIV.C.CH505 and treated with long-term ART. Rebound viremia was detected within 7 to 35 days of ATI in 9 of 10 animals, with posttreatment control of viremia seen in 5 of 5 Mamu-A*01+ macaques. Single-genome sequencing revealed that initial rebound virus was similar to viral DNA present in CD4+ T cells from blood, rectum, and lymph nodes before ATI. We assessed the earliest sites of viral reactivation immediately following ATI using ImmunoPET imaging. The largest increase in signal that preceded detectable viral RNA in plasma was found in the gastrointestinal (GI) tract, a site with relatively high SHIV RNA/DNA ratios in CD4+ T cells before ATI. Thus, the GI tract may be an initial source of rebound virus, but as ATI progresses, viral reactivation in other tissues likely contributes to the composition of plasma virus. Our study provides potentially novel insight into the features of viral rebound in pediatric infection and highlights the application of a noninvasive technique to monitor areas of HIV-1 expression in children.


Asunto(s)
Antirretrovirales/uso terapéutico , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Viremia/etiología , Animales , Femenino , Macaca , Masculino , Viremia/patología
6.
Nat Biotechnol ; 39(6): 717-726, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33536629

RESUMEN

Cas13a has been used to target RNA viruses in cell culture, but efficacy has not been demonstrated in animal models. In this study, we used messenger RNA (mRNA)-encoded Cas13a for mitigating influenza virus A and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in mice and hamsters, respectively. We designed CRISPR RNAs (crRNAs) specific for PB1 and highly conserved regions of PB2 of influenza virus, and against the replicase and nucleocapsid genes of SARS-CoV-2, and selected the crRNAs that reduced viral RNA levels most efficiently in cell culture. We delivered polymer-formulated Cas13a mRNA and the validated guides to the respiratory tract using a nebulizer. In mice, Cas13a degraded influenza RNA in lung tissue efficiently when delivered after infection, whereas in hamsters, Cas13a delivery reduced SARS-CoV-2 replication and reduced symptoms. Our findings suggest that Cas13a-mediated targeting of pathogenic viruses can mitigate respiratory infections.


Asunto(s)
COVID-19/terapia , Gripe Humana/terapia , ARN Mensajero/farmacología , SARS-CoV-2/genética , Animales , COVID-19/genética , COVID-19/virología , Sistemas CRISPR-Cas/genética , Cricetinae , Modelos Animales de Enfermedad , Humanos , Gripe Humana/genética , Gripe Humana/virología , Ratones , Orthomyxoviridae/efectos de los fármacos , Orthomyxoviridae/genética , Orthomyxoviridae/patogenicidad , ARN Mensajero/genética , ARN Viral/genética , Sistema Respiratorio/efectos de los fármacos , Sistema Respiratorio/metabolismo , SARS-CoV-2/patogenicidad
7.
RSC Adv ; 10(24): 14170-14197, 2020 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-35498463

RESUMEN

Nitrogen containing heterocycles are of immense research interest because they are often found as naturally occurring bioactive compounds. The prominence of N-heterocycles makes it vital to develop methods to increase their synthetic efficiencies and probe the effects of their modifications on biological efficacy. Medicinal chemists have exploited microwave-assisted organic synthesis (MAOS) to facilitate the development of complex heterocyclic structures. MAOS is a growing synthetic methodology among medicinal chemists and has proven to be more efficient in terms of reaction yield, reaction time, product purity and environmental friendliness for many reactions when compared to conventional thermal methods for cycloaddition and selective functionalization. The importance of nitrogen containing ring systems in medicine cannot be understated, as such ring systems have shown to be applicable in compounds such as vitamins, herbicides, anti-fungal agents, anti-bacterial agents and anti-cancer agents, among other things. The significance of these applications has created an unprecedented need for more efficient synthetic methods. This review presents an overview of MAOS and its role in recent and pressing advancements for the synthesis of small- and medium-sized nitrogen containing heterocycles, including pyrroles, indoles, pyridines, pyrrolidines, imidazoles, pyrazoles, pyrazolines, lactams, and 1,2,3-triazoles, which are significant scaffolds for compounds with medicinal uses.

8.
J Sci Food Agric ; 98(12): 4561-4569, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29505171

RESUMEN

BACKGROUND: For the processing industry, it is crucial to know what effect the roasting process and conditions have on hazelnut quality. The present study investigates, for the first time, the effects of hot-air and infrared (IR) roasting at different time-temperature combinations on Tonda Gentile Trilobata hazelnut: whole kernels and derived processing products (paste and oil). RESULTS: The nutritional and physical characteristics of hazelnuts and processing products were investigated to determine the influence of the different roasting conditions as a function of intended use. The antioxidant profile (2.2-diphenyl-1-picrylhydrazyl radical, oxygen radical absorbance capacity and total phenolic content) were analyzed on roasted hazelnut and paste extracts. For a comprehensive understanding of the complex biochemical phenomena occurring during roasting, E-nose and near-IR spectroscopy were also applied. All analytical data were processed using univariate and multivariate data analyses. Hazelnuts derived from IR roasting at higher temperatures (195 °C) showed a richer antioxidant profile and a more intense flavour. On the other hand, the yield associated with the oil extraction under the same conditions was unsatisfactory, making this process completely inadequate for oil production. Oil obtained by hot-air roasting and IR roasting at lower temperature (135 °C) was found to be of good quality, showing rather similar acidity grade, peroxide number and acidic composition. In particular, a slightly but significantly lower acidity was related to lower roasting temperatures (0.21-0.22% versus 0.27% for higher temperatures). All roasting conditions tested allowed the quantitative homogeneous hazelnut paste to be obtained and, from a rheological point of view, a higher roasting temperatures resulted in pastes characterized by higher density and viscosity values. CONCLUSION: The use of IR was found to be a promising alternative method for hazelnut roasting, as a result of its capability with respect to preserving nutritional values and enhancing organoleptic quality. © 2018 Society of Chemical Industry.


Asunto(s)
Culinaria/métodos , Corylus/química , Nueces/efectos de la radiación , Antioxidantes/química , Culinaria/instrumentación , Corylus/efectos de la radiación , Calor , Rayos Infrarrojos , Valor Nutritivo , Nueces/química , Fenoles/química , Extractos Vegetales/química
9.
RSC Adv ; 8(13): 7029-7039, 2018 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-35540310

RESUMEN

A novel protocol for microwave-assisted alkyne semi-hydrogenation under heterogeneous catalysis in a continuous flow reactor is reported herein. This challenging task has been accomplished using a multifaceted strategy which includes the ultrasound-assisted preparation of Pd nanoparticles (average Ø 3.0 ± 0.5 nm) that were synthesized on the µ-metric pores of sintered alumina spheres (Ø 0.8 mm) and a continuous flow reaction under H2 (flow rate 7.5 mL min-1) in a microwave reactor (counter-pressure 4.5 bar). The semi-hydrogenation of 2-butyne-1,4-diol in ethanol was chosen as a model reaction for the purposes of optimization. The high catalyst efficiency of the process, in spite of the low Pd loading (Pd content 111.15 mg kg-1 from ICP-MS), is due to the pivotal role of ultrasound in generating a regular distribution of Pd nanoparticles across the entire support surface. Ultrasound promotes the nucleation, rather than the growth, of crystalline Pd nanoparticles and does so within a particularly narrow Gaussian size distribution. High conversion (>90.5%) and selectivity to (Z)-2-butene-1,4-diol (95.20%) have been achieved at an alkyne solution flow rate of 10 mL min-1. The lead-free, alumina-stabilized Pd catalyst was fully characterized by TEM, HR-TEM, EDX, IR, XRPD and AAS. Highly dispersed Pd nanoparticles have proven themselves to be stable under the reaction conditions employed. The application of the method is subject to the dielectric properties of substrates and solvents, and is therefore hardly applicable to apolar alkynes. Considering the small volume of the reaction chamber, microwave-assisted flow hydrogenation has proven itself to be a safe procedure and one that is suitable for further scaling up to industrial application.

10.
Molecules ; 21(3): 253, 2016 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-26927033

RESUMEN

The present review deals with the recent achievements and impressive potential applications of microwave (MW) heating to promote heterogeneous reactions under gas pressure. The high versatility of the latest generation of professional reactors combines extreme reaction conditions with safer and more efficient protocols. The double aims of this survey are to provide a panoramic snapshot of MW-assisted organic reactions with gaseous reagents, in particular CO and CO2, and outline future applications. Stubborn and time-consuming carbonylation-like heterogeneous reactions, which have not yet been studied under dielectric heating, may well find an outstanding ally in the present protocol.


Asunto(s)
Dióxido de Carbono/química , Monóxido de Carbono/química , Técnicas de Química Sintética/métodos , Alquinos/química , Compuestos de Anilina/química , Catálisis , Calor , Microondas , Presión
11.
Ultrason Sonochem ; 27: 30-36, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26186817

RESUMEN

An ultrasound-assisted three-component, one-pot domino reaction with ferrocenecarboxaldehyde is herein reported. The sequence of reactions entails the allylindation and dehydrative alkylation of stabilized C-nucleophiles (e.g. electron-rich-(hetero)aromatics and stabilized enols) and N-nucleophiles (e.g. azoles). Sonochemical reactions have been performed in three different high-intensity reactors: a bath (20.3 kHz, 60 W), as well as two cup horns working at 19.9 kHz (75 W) and 300.5 kHz (70 W) giving a library of 18 new ferrocenyl derivatives.

12.
Molecules ; 20(2): 2837-49, 2015 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-25671367

RESUMEN

The ball-mill-based mechanochemical activation of metallic copper powder facilitates solvent-free alkyne-azide click reactions (CuAAC). All parameters that affect reaction rate (i.e., milling time, revolutions/min, size and milling ball number) have been optimized. This new, efficient, facile and eco-friendly procedure has been tested on a number of different substrates and in all cases afforded the corresponding 1,4-disubstituted 1,2,3-triazole derivatives in high yields and purities. The final compounds were isolated in almost quantitative overall yields after simple filtration, making this procedure facile and rapid. The optimized CuAAC protocol was efficiently applied even with bulky functionalized ß-cyclodextrins (ß-CD) and scaled-up to 10 g of isolated product.


Asunto(s)
Alquinos/química , Azidas/química , Cobre/química , Reacción de Cicloadición/instrumentación , Catálisis , Química Clic , Reacción de Cicloadición/métodos , Modelos Químicos , Estructura Molecular , Solventes , beta-Ciclodextrinas/síntesis química
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...