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1.
Athens Journal of Education ; 10(2):213-231, 2023.
Artículo en Inglés | ProQuest Central | ID: covidwho-20242811

RESUMEN

The epistemological beliefs of students are an important area for higher education research. This paper firstly reports on a research review concerning the impact of epistemological beliefs on academic outcomes. This review indicates that students' epistemological beliefs are an influence on their engagement with learning and academic success, and that educators should consider them in developing learning experiences. This issue became particularly pertinent in the context of a global pandemic that necessitated an international trend in moving to online distance education, where student disengagement is more likely to occur. However, research into distance education students' epistemological beliefs emerged as an under-researched field. Consequently, an empirical questionnaire study was conducted with data collected from 550 distance education students. A principal component analysis indicated that particular epistemological beliefs were significantly associated with students' enjoyment of studying online. Their beliefs regarding the role of fun in online learning materials and activities are discussed, and the usefulness of considering fun and epistemological beliefs as factors within distance learning in higher education is highlighted. [Note: The page range (213-232) shown on the PDF is incorrect. The correct page range is 213-231.]

2.
J Hepatol ; 2022 Nov 02.
Artículo en Inglés | MEDLINE | ID: covidwho-2302356

RESUMEN

BACKGROUND & AIMS: The LIVIFY trial investigated the safety, tolerability, and efficacy, of Vonafexor, a second-generation, non-bile acid farnesoid X receptor agonist in patients with suspected fibrotic non-alcoholic steatohepatitis (NASH). METHODS: This double-blind phase 2a study was conducted in two parts. Patients were randomised (1:1:1:1) to receive placebo, Vonafexor 100 mg twice daily (VONA-100BID), Vonafexor 200 mg once daily (VONA-200QD), or 400 mg Vonafexor QD (VONA-400QD) in Part A (safety run-in, pharmacokinetics/pharmacodynamics) or placebo, Vonafexor 100 mg QD (VONA-100QD), or VONA-200QD (1:1:1) in Part B. Efficacy endpoints were reduction in liver fat content (LFC) from baseline to Week 12 by magnetic resonance imaging proton density fat fraction (MRI-PDFF, primary), imaging biomarker of fibrotic steatohepatitis (corrected T1 signal), and liver enzymes. RESULTS: One hundred and twenty patients were randomised (Part A, n=24; Part B, n=96). In Part B, there was a significant reduction in least-square mean (SE) absolute change in LFC from baseline to Week 12 for VONA-100QD, (-6.3% [0.9]), VONA-200QD (-5.4% [0.9]), versus placebo (-2.3% [0.9], p=0.002 and 0.012, respectively). A >30% relative LFC reduction was achieved by 50.0% and 39.3% of patients in the VONA-100QD and VONA-200QD arms, respectively, but only in 12.5% in the placebo arm. Reductions in body weight, liver enzymes, and corrected T1 were also observed with Vonafexor. Creatinine based glomerular filtration rate (eGFR) improved in the active arms but not the placebo arm. Mild to moderate generalised pruritus was reported in 6.3%, 9.7%, and 18.2% of subjects in the placebo, VONA-100QD, and VONA-200QD arms, respectively. CONCLUSIONS: In patients with suspected fibrotic NASH, Vonafexor was safe and induced potent liver fat reduction, improvement in liver enzymes, weight loss, and a possible renal benefit. CLINICAL TRIAL NUMBER (EUDRACT): 2018-003119-22. GOV IDENTIFIER: NCT03812029. IMPACT AND IMPLICATIONS: NASH has become a leading cause for chronic liver disease and patients are also at higher risk for the development of chronic kidney disease. There are no approved therapies and only few options to treat this population. LIVIFY Phase 2a trial results show that single daily administration of oral Vonafexor, a FXR agonist, leads in the short term to a reduction in liver fat, liver enzymes, fibrosis biomarkers, body weight and abdominal circumference, and a possible improvement in kidney function, while possible mild moderate pruritus (a peripheral FXR class effect) and an LDL-Cholesterol increase are manageable with lower doses and statins. These results support exploration in longer and larger trials to ultimately provide therapies for the unmet medical need in NASH.

3.
Sci Immunol ; 7(74): eabo3425, 2022 08 12.
Artículo en Inglés | MEDLINE | ID: covidwho-1832328

RESUMEN

Neutralizing antibodies that recognize the SARS-CoV-2 spike glycoprotein are the principal host defense against viral invasion. Variants of SARS-CoV-2 bear mutations that allow escape from neutralization by many human antibodies, especially those in widely distributed ("public") classes. Identifying antibodies that neutralize these variants of concern and determining their prevalence are important goals for understanding immune protection. To determine the Delta and Omicron BA.1 variant specificity of B cell repertoires established by an initial Wuhan strain infection, we measured neutralization potencies of 73 antibodies from an unbiased survey of the early memory B cell response. Antibodies recognizing each of three previously defined epitopic regions on the spike receptor binding domain (RBD) varied in neutralization potency and variant-escape resistance. The ACE2 binding surface ("RBD-2") harbored the binding sites of neutralizing antibodies with the highest potency but with the greatest sensitivity to viral escape; two other epitopic regions on the RBD ("RBD-1" and "RBD-3") bound antibodies of more modest potency but greater breadth. The structures of several Fab:spike complexes that neutralized all five variants of concern tested, including one Fab each from the RBD-1, -2, and -3 clusters, illustrated the determinants of broad neutralization and showed that B cell repertoires can have specificities that avoid immune escape driven by public antibodies. The structure of the RBD-2 binding, broad neutralizer shows why it retains neutralizing activity for Omicron BA.1, unlike most others in the same public class. Our results correlate with real-world data on vaccine efficacy, which indicate mitigation of disease caused by Omicron BA.1.


Asunto(s)
COVID-19 , SARS-CoV-2 , Anticuerpos Neutralizantes/química , Anticuerpos Antivirales , Humanos , Pruebas de Neutralización , SARS-CoV-2/genética
5.
Nat Med ; 27(7): 1262-1271, 2021 07.
Artículo en Inglés | MEDLINE | ID: covidwho-1550325

RESUMEN

Preclinical and clinical data suggest that fibroblast growth factor 21 (FGF21) is anti-fibrotic, improves metabolic status and has potential to treat non-alcoholic steatohepatitis (NASH). We assessed the safety and efficacy of efruxifermin, a long-acting Fc-FGF21 fusion protein, for the treatment of NASH. BALANCED was a randomized, placebo-controlled study in patients with NASH conducted at 27 centers in the United States (ClinicalTrials.gov NCT03976401 ). Eighty patients, stratified by hepatic fat fraction (HFF) and fibrosis stage, were randomized using a centrally administered minimization algorithm 1:1:1:1 to receive placebo (n = 21) or efruxifermin 28 mg (n = 19), efruxifermin 50 mg (n = 20) or efruxifermin 70 mg (n = 20) via weekly subcutaneous injection for 16 weeks. The primary endpoint-absolute change from baseline in HFF measured as magnetic resonance imaging-proton density fat fraction at week 12-was met. For the full analysis set, the least squares mean absolute changes (one-sided 97.5% confidence interval) from baseline in HFF were -12.3% (-infinity (-inf), -10.3), -13.4% (-inf, -11.4) and -14.1% (-inf, -12.1) in the 28-, 50- and 70-mg groups, respectively, versus 0.3% (-inf, 1.6) in the placebo group, with statistically significant differences between efruxifermin groups and placebo (P < 0.0001 each). Overall, 70 of 79 patients who received the study drug (89%) experienced at least one treatment-emergent adverse event (TEAE), with the majority grade 1-2 (64 (81%)), five (6%) grade 3 and one grade 4. The most commonly reported drug-related TEAEs were grade 1-2 gastrointestinal (36 (46%)). Treatment with efruxifermin significantly reduced HFF in patients with F1-F3 stage NASH, with an acceptable safety profile.


Asunto(s)
Factores de Crecimiento de Fibroblastos/uso terapéutico , Fragmentos Fc de Inmunoglobulinas/uso terapéutico , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Proteínas Recombinantes de Fusión/uso terapéutico , Índice de Masa Corporal , Método Doble Ciego , Femenino , Humanos , Hígado/patología , Cirrosis Hepática/tratamiento farmacológico , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
6.
Lancet Gastroenterol Hepatol ; 6(11): 889-902, 2021 11.
Artículo en Inglés | MEDLINE | ID: covidwho-1433978

RESUMEN

BACKGROUND: AMP kinase (AMPK) is an energy sensor implicated in regulation of lipid metabolism, inflammation, and insulin sensitivity. We aimed to assess efficacy and safety of PXL770, a novel direct AMPK activator, in patients with non-alcoholic fatty liver disease (NAFLD). METHODS: STAMP-NAFLD, a randomised, double-blind, placebo-controlled phase 2a study, was done across 15 US clinical sites. Patients aged 18-75 years with liver fat content of at least 10% at baseline when assessed by MRI-proton density fat fraction (MRI-PDFF) were eligible. Patients were randomly assigned (1:1:1:1), via an interactive web response system, to receive oral PXL770 250 mg once daily, 250 mg twice daily, or 500 mg once daily, or matched placebo. Patients were stratified according to type 2 diabetes status and study site. The primary endpoint was relative change in liver fat content from baseline compared with placebo at week 12, assessed by MRI-PDFF. The primary endpoint was analysed in an ANCOVA model with treatment and stratification criteria as factors and baseline liver fat content as a covariate in the modified intention-to-treat population, defined as all as-randomised patients who received at least one dose of study treatment. Safety was analysed in the safety population, defined as all as-treated patients receiving at least one dose of the study treatment. The trial has been completed and the final results are reported. The trial is registered with ClinicalTrials.gov, NCT03763877. FINDINGS: Between March 29, 2019, and March 13, 2020, 387 patients were screened, of whom 120 were included in the modified intention-to-treat and safety analyses (30 in the 250 mg once daily group, 30 in the 250 mg twice daily group, 29 in the 500 mg once daily group, and 31 in the placebo group). The mean relative change from baseline in liver fat content at week 12 was -1·1% in the placebo group, -1·0% in the 250 mg once daily group (mean difference versus placebo 0·1% [95% CI -15·4 to 15·7], p=0·99), -14·3% in the 250 mg twice daily group (-13·1% [-28·1 to 1·8], p=0·084), and -14·7% in the 500 mg once daily group (-13·5% [-28·5 to 1·4], p=0·076). At least one treatment-emergent adverse event occurred in 23 (77%) of 30 patients in the 250 mg once daily group, 20 (67%) of 30 patients in the 250 mg twice daily group, 21 (72%) of 29 patients in the 500 mg once daily group, and 21 (68%) of 31 patients in the placebo group. The most common treatment-emergent adverse event was diarrhoea (five [17%] of patients in the 250 mg once daily group, seven [23%] in the 250 mg twice daily group, six [21%] in the 500 mg once daily group, and none in the placebo group). No life-threatening events or treatment-related deaths occurred. INTERPRETATION: PXL770 treatment did not meet the primary outcome of liver fat improvement compared with placebo. Treatment was well tolerated. Given indications that metabolic features improved with PXL770 treatment, AMPK activation might be a promising pharmacological target for patients with type 2 diabetes and NAFLD, and could also be considered for further assessment in patients with non-alcoholic steatohepatitis. FUNDING: Poxel.


Asunto(s)
Adenilato Quinasa/metabolismo , Reguladores del Metabolismo de Lípidos/uso terapéutico , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Piridonas/uso terapéutico , Tetrahidronaftalenos/uso terapéutico , Administración Oral , Adolescente , Adulto , Anciano , Método Doble Ciego , Esquema de Medicación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Piridonas/efectos adversos , Tetrahidronaftalenos/efectos adversos , Resultado del Tratamiento , Adulto Joven
7.
ACS Infect Dis ; 7(9): 2591-2595, 2021 09 10.
Artículo en Inglés | MEDLINE | ID: covidwho-1373350

RESUMEN

The main protease (Mpro) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the cause of coronavirus disease (COVID-19), is an ideal target for pharmaceutical inhibition. Mpro is conserved among coronaviruses and distinct from human proteases. Viral replication depends on the cleavage of the viral polyprotein at multiple sites. We present crystal structures of SARS-CoV-2 Mpro bound to two viral substrate peptides. The structures show how Mpro recognizes distinct substrates and how subtle changes in substrate accommodation can drive large changes in catalytic efficiency. One peptide, constituting the junction between viral nonstructural proteins 8 and 9 (nsp8/9), has P1' and P2' residues that are unique among the SARS-CoV-2 Mpro cleavage sites but conserved among homologous junctions in coronaviruses. Mpro cleaves nsp8/9 inefficiently, and amino acid substitutions at P1' or P2' can enhance catalysis. Visualization of Mpro with intact substrates provides new templates for antiviral drug design and suggests that the coronavirus lifecycle selects for finely tuned substrate-dependent catalytic parameters.


Asunto(s)
COVID-19 , Proteasas 3C de Coronavirus/metabolismo , SARS-CoV-2 , Antivirales , Humanos , Péptido Hidrolasas , Proteínas no Estructurales Virales
8.
Cell ; 184(19): 4969-4980.e15, 2021 09 16.
Artículo en Inglés | MEDLINE | ID: covidwho-1333275

RESUMEN

Memory B cell reserves can generate protective antibodies against repeated SARS-CoV-2 infections, but with unknown reach from original infection to antigenically drifted variants. We charted memory B cell receptor-encoded antibodies from 19 COVID-19 convalescent subjects against SARS-CoV-2 spike (S) and found seven major antibody competition groups against epitopes recurrently targeted across individuals. Inclusion of published and newly determined structures of antibody-S complexes identified corresponding epitopic regions. Group assignment correlated with cross-CoV-reactivity breadth, neutralization potency, and convergent antibody signatures. Although emerging SARS-CoV-2 variants of concern escaped binding by many members of the groups associated with the most potent neutralizing activity, some antibodies in each of those groups retained affinity-suggesting that otherwise redundant components of a primary immune response are important for durable protection from evolving pathogens. Our results furnish a global atlas of S-specific memory B cell repertoires and illustrate properties driving viral escape and conferring robustness against emerging variants.

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