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1.
BMJ Open ; 14(6): e080151, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38950991

RESUMEN

INTRODUCTION: Amblyopia is a neurodevelopmental vision disorder typically affecting one eye, resulting in compromised binocular function. While evidence-based treatments exist for children, there are no widely accepted treatments for adults. This trial aims to assess the efficacy of appropriate optical treatment in improving vision and visual functions in adults with amblyopia. This is hypothesised to significantly improve visual acuity of the amblyopic eye and other visual functions. METHODS AND ANALYSIS: SPEctacle Correction for the TReatment of Amblyopia is a prospective non-randomised interventional trial. The following criteria for amblyopia will be used: best corrected visual acuity (BCVA) in the amblyopic eye of 0.3 to 1.0 (inclusive) logMAR VA and in the fellow eye, 0.1 logMAR or better, with an interocular VA difference of ≥2 logMAR lines. Eligible participants aged 18-39 will receive full/near-full optical treatment requiring wear for at least half their waking hours for the trial duration. A difference of ≥1.00D spherical equivalent between a participant's current refractive correction and the study prescription is required for eligibility. Primary outcome is the change in amblyopic eye BCVA from baseline to 24-week postenrolment. Secondary outcomes include distance and near VA of both eyes, stereoacuity, contrast sensitivity, interocular suppression, angle of strabismus and fixation stability measured at monthly intervals. Visual evoked potentials will also be measured at baseline, week 12 and week 24. Treatment compliance and quality of life for all participants will be monitored.Analyses comparing baseline and week 24 will utilise pairwise comparisons. Linear mixed models will be fitted to the data for measures taken monthly. This allows estimates and inferences to be drawn from the coefficients of the model, while handling missing data. ETHICS AND DISSEMINATION: Human ethics approval was obtained from the respective ethics board of the Hong Kong Polytechnic University (HSEARS20210915002) and the University of Waterloo (#44235). The study protocol will conform to the principles of the Declaration of Helsinki. Results will be disseminated through peer-reviewed journals and conferences. TRIAL REGISTRATION NUMBER: NCT05394987; clinicaltrials.org.


Asunto(s)
Ambliopía , Anteojos , Agudeza Visual , Humanos , Ambliopía/terapia , Ambliopía/fisiopatología , Estudios Prospectivos , Adulto , Adulto Joven , Adolescente , Masculino , Femenino , Resultado del Tratamiento , Ensayos Clínicos Controlados no Aleatorios como Asunto , Visión Binocular/fisiología
3.
Optom Vis Sci ; 101(6): 305-320, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38990233

RESUMEN

BACKGROUND: Visual perceptual learning (PL) shows promise for enhancing visual functions in individuals with visual impairment. OBJECTIVE: This systematic review aimed to evaluate the effectiveness of PL in improving visual function. STUDY ELIGIBILITY: Eligible studies were those examining the efficacy of PL in individuals with low vision. STUDY APPRAISAL AND SYNTHESIS METHODS: The review protocol was registered with the international Prospective Register of Systematic Reviews (ID CRD42022327545) and adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Screened studies were synthesized using random-effects meta-analysis and narrative synthesis following Synthesis Without Meta-analysis guidelines. The quality of the evidence was assessed using the Cochrane risk-of-bias tool and the JBI Critical Appraisal Tool for Quasi-Experimental studies. RESULTS: Fifty studies were included, covering various visual impairments and employing different PL interventions. Most studies had low risk of bias. Meta-analysis showed significant improvement in visual search for individuals with cortical blindness (Hedges' g = 0.71; 95% confidence interval, 0.48 to 0.93; p=0.002); all other analyses did not show significant improvements-reading in central vision loss and cortical blindness, and visual field in peripheral vision loss and cortical blindness. However, the narrative synthesis provided evidence showing effectiveness, particularly in individuals with central vision loss and cortical blindness, demonstrating positive effects on reading, contrast sensitivity, visual field, and motion perception. LIMITATIONS: Variations in study design, PL protocols, outcome measures, and measurement methods introduced heterogeneity, limiting the analysis. CONCLUSIONS: The efficacy of PL in vision rehabilitation remains uncertain. Although meta-analysis results were mostly inconclusive, the narrative synthesis indicated improved visual functions following PL, consistent with individual study findings. IMPLICATIONS OF KEY FINDINGS: Future research should optimize intervention parameters, explore long-term effects, and assess generalizability across diverse populations and visual impairment etiologies. Larger randomized controlled trials using standardized outcome measures are needed to advance the field.


Asunto(s)
Baja Visión , Percepción Visual , Humanos , Baja Visión/rehabilitación , Baja Visión/fisiopatología , Percepción Visual/fisiología , Aprendizaje/fisiología , Agudeza Visual/fisiología
5.
Phys Chem Chem Phys ; 26(29): 19900-19907, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-38990130

RESUMEN

Hydroxylation reactions are important in biological processes and synthetic schemes. Many challenging hydroxylation reactions have been achieved using photoredox catalytic methods. For the oxidative hydroxylation of arylboronic acids, methylene blue has been used successfully as a photoredox catalyst to produce phenyl groups. Here we use broadband transient absorption spectroscopy to determine the mechanism of the photoredox catalytic reaction of methylene blue with phenylboronic acid in the presence of N,N-diisopropylethylamine. Our results show that the reaction proceeds through the triplet state of methylene blue in the presence of oxygen, generating superoxide radical anions. In addition, we observe dimerization of the methylene blue at typical catalytic loadings. As these dimers do not participate in the reaction, increasing the concentration of methylene blue is potentially detrimental to the overall yield.

8.
Nature ; 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39026069
10.
Artículo en Inglés | MEDLINE | ID: mdl-38937991

RESUMEN

BACKGROUND: For children with constipation and fecal incontinence treated with antegrade continence enemas (ACE), a fluoroscopic study with contrast administered via appendicostomy/cecostomy can define the anatomy of the colon and simulate the flush to investigate associated symptoms or inadequate response. These studies can at times show retrograde flow into the small intestine. Our objective was to investigate the significance of this finding. METHODS: We reviewed studies at our institution with contrast administered via appendicostomy/cecostomy in children treated with ACE, identifying those demonstrating retrograde flow of contrast. We recorded demographics, medical history, interventions, and outcomes. RESULTS: We identified 162 studies (52% male, median age 10.7 years) with contrast via appendicostomy (76%) or cecostomy (24%). Diagnoses included anorectal malformation (38%), spinal cord anomaly (26%), functional constipation (24%), colonic dysmotility (18%), and Hirschsprung disease (12%). Fifty-nine (36%) studies showed retrograde flow: 28/59 children (48%) were not responding adequately and 21/59 (36%) had symptoms with ACE. Children with retrograde flow were more likely to have symptoms with ACE than those without (36% vs. 15%, p < 0.01). Fourteen children underwent interventions for this finding, including administering flushes more distally (4/8 responded), changing positioning of the child during flush administration, (1/2 responded), and slowing administration (1/1 responded). Retrograde flow was associated with younger age (p < 0.01), not sex or underlying diagnosis. CONCLUSION: Identifying retrograde flow during studies with contrast administered via appendicostomy/cecostomy can be useful for children with a poor response or symptoms associated with ACE, as adjustments to the mechanics of the flush can alleviate those symptoms. LEVEL OF EVIDENCE: Prognostic study, Level III.

14.
Lancet ; 403(10442): 2381-2394, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38735299

RESUMEN

BACKGROUND: Motor neuron disease is a progressive, fatal neurodegenerative disease for which there is no cure. Acceptance and Commitment Therapy (ACT) is a psychological therapy incorporating acceptance, mindfulness, and behaviour change techniques. We aimed to evaluate the effectiveness of ACT plus usual care, compared with usual care alone, for improving quality of life in people with motor neuron disease. METHODS: We conducted a parallel, multicentre, two-arm randomised controlled trial in 16 UK motor neuron disease care centres or clinics. Eligible participants were aged 18 years or older with a diagnosis of definite or laboratory-supported probable, clinically probable, or possible familial or sporadic amyotrophic lateral sclerosis; progressive muscular atrophy; or primary lateral sclerosis; which met the World Federation of Neurology's El Escorial diagnostic criteria. Participants were randomly assigned (1:1) to receive up to eight sessions of ACT adapted for people with motor neuron disease plus usual care or usual care alone by a web-based system, stratified by site. Participants were followed up at 6 months and 9 months post-randomisation. Outcome assessors and trial statisticians were masked to treatment allocation. The primary outcome was quality of life using the McGill Quality of Life Questionnaire-Revised (MQOL-R) at 6 months post-randomisation. Primary analyses were multi-level modelling and modified intention to treat among participants with available data. This trial was pre-registered with the ISRCTN Registry (ISRCTN12655391). FINDINGS: Between Sept 18, 2019, and Aug 31, 2022, 435 people with motor neuron disease were approached for the study, of whom 206 (47%) were assessed for eligibility, and 191 were recruited. 97 (51%) participants were randomly assigned to ACT plus usual care and 94 (49%) were assigned to usual care alone. 80 (42%) of 191 participants were female and 111 (58%) were male, and the mean age was 63·1 years (SD 11·0). 155 (81%) participants had primary outcome data at 6 months post-randomisation. After controlling for baseline scores, age, sex, and therapist clustering, ACT plus usual care was superior to usual care alone for quality of life at 6 months (adjusted mean difference on the MQOL-R of 0·66 [95% CI 0·22-1·10]; d=0·46 [0·16-0·77]; p=0·0031). Moderate effect sizes were clinically meaningful. 75 adverse events were reported, 38 of which were serious, but no adverse events were deemed to be associated with the intervention. INTERPRETATION: ACT plus usual care is clinically effective for maintaining or improving quality of life in people with motor neuron disease. As further evidence emerges confirming these findings, health-care providers should consider how access to ACT, adapted for the specific needs of people with motor neuron disease, could be provided within motor neuron disease clinical services. FUNDING: National Institute for Health and Care Research Health Technology Assessment and Motor Neurone Disease Association.


Asunto(s)
Terapia de Aceptación y Compromiso , Enfermedad de la Neurona Motora , Calidad de Vida , Humanos , Terapia de Aceptación y Compromiso/métodos , Masculino , Femenino , Persona de Mediana Edad , Enfermedad de la Neurona Motora/terapia , Enfermedad de la Neurona Motora/psicología , Reino Unido , Anciano , Resultado del Tratamiento
16.
JAMA Netw Open ; 7(5): e2413508, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38805222

RESUMEN

Importance: Understanding the effect of antenatal magnesium sulfate (MgSO4) treatment on functional connectivity will help elucidate the mechanism by which it reduces the risk of cerebral palsy and death. Objective: To determine whether MgSO4 administered to women at risk of imminent preterm birth at a gestational age between 30 and 34 weeks is associated with increased functional connectivity and measures of functional segregation and integration in infants at term-equivalent age, possibly reflecting a protective mechanism of MgSO4. Design, Setting, and Participants: This cohort study was nested within a randomized placebo-controlled trial performed across 24 tertiary maternity hospitals. Participants included infants born to women at risk of imminent preterm birth at a gestational age between 30 and 34 weeks who participated in the MAGENTA (Magnesium Sulphate at 30 to 34 Weeks' Gestational Age) trial and underwent magnetic resonance imaging (MRI) at term-equivalent age. Ineligibility criteria included illness precluding MRI, congenital or genetic disorders likely to affect brain structure, and living more than 1 hour from the MRI center. One hundred and fourteen of 159 eligible infants were excluded due to incomplete or motion-corrupted MRI. Recruitment occurred between October 22, 2014, and October 25, 2017. Participants were followed up to 2 years of age. Analysis was performed from February 1, 2021, to February 27, 2024. Observers were blind to patient groupings during data collection and processing. Exposures: Women received 4 g of MgSO4 or isotonic sodium chloride solution given intravenously over 30 minutes. Main Outcomes and Measures: Prior to data collection, it was hypothesized that infants who were exposed to MgSO4 would show enhanced functional connectivity compared with infants who were not exposed. Results: A total of 45 infants were included in the analysis: 24 receiving MgSO4 treatment and 21 receiving placebo; 23 (51.1%) were female and 22 (48.9%) were male; and the median gestational age at scan was 40.0 (IQR, 39.1-41.1) weeks. Treatment with MgSO4 was associated with greater voxelwise functional connectivity in the temporal and occipital lobes and deep gray matter structures and with significantly greater clustering coefficients (Hedge g, 0.47 [95% CI, -0.13 to 1.07]), transitivity (Hedge g, 0.51 [95% CI, -0.10 to 1.11]), local efficiency (Hedge g, 0.40 [95% CI, -0.20 to 0.99]), and global efficiency (Hedge g, 0.31 [95% CI, -0.29 to 0.90]), representing enhanced functional segregation and integration. Conclusions and Relevance: In this cohort study, infants exposed to MgSO4 had greater voxelwise functional connectivity and functional segregation, consistent with increased brain maturation. Enhanced functional connectivity is a possible mechanism by which MgSO4 protects against cerebral palsy and death.


Asunto(s)
Sulfato de Magnesio , Imagen por Resonancia Magnética , Humanos , Sulfato de Magnesio/farmacología , Sulfato de Magnesio/uso terapéutico , Femenino , Embarazo , Recién Nacido , Masculino , Adulto , Edad Gestacional , Estudios de Cohortes , Nacimiento Prematuro , Lactante , Encéfalo/efectos de los fármacos , Encéfalo/diagnóstico por imagen , Atención Prenatal/métodos , Parálisis Cerebral/prevención & control
17.
ACS Macro Lett ; 13(6): 720-725, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38804976

RESUMEN

The Rouse dynamics of polymer chains in model nanocomposite polyethylene oxide/silica nanoparticles (NPs) was investigated using quasielastic neutron scattering. The apparent Rouse rate of the polymer chains decreases as the particle loading increases. However, there is no evidence of an immobile segment population on the probed time scale of tens of ps. The slowing down of the dynamics is interpreted in terms of modified Rouse models for the chains in the NP interphase region. Thus, two chain populations, one bulk-like and the other characterized by a suppression of Rouse modes, are identified. The spatial extent of the interphase region is estimated to be about twice the adsorbed layer thickness, or ≈2 nm. These findings provide a detailed description of the suppression of the chain dynamics on the surface of NPs. These results are relevant insights on surface effects and confinement and provide a foundation for the understanding of the rheological properties of polymer nanocomposites with well-dispersed NPs.

18.
Front Neurosci ; 18: 1341307, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38721051

RESUMEN

Visual cortex anodal transcranial direct current stimulation (a-tDCS) has been shown to reduce crowding in normal peripheral vision and may improve the reading of English words in patients with macular degeneration. Given the different visual requirements of reading English words and Chinese characters, the effect of a-tDCS on peripheral reading performance in English might differ from Chinese. This study recruited 20 participants (59-73 years of age) with normal vision and tested the hypothesis that a-tDCS would improve the reading of Chinese characters presented at 10° eccentricity compared with sham stimulation. Chinese sentences of different print sizes and exposure durations were presented one character at a time, 10° below or to the left of fixation. The individual critical print size (CPS) - the smallest print size eliciting the maximum reading speed (MRS) - was determined. Reading accuracies for characters presented 0.2 logMAR smaller than the individually fitted CPS were measured at four time points: before, during, 5 min after, and 30 min after receiving active or sham visual cortex a-tDCS. Participants completed both the active and sham sessions in a random order following a double-blind, within-subject design. No effect of active a-tDCS on reading accuracy was observed, implying that a single session of a-tDCS did not improve Chinese character reading in normal peripheral vision. This may suggest that a-tDCS does not significantly reduce the crowding elicited within a single Chinese character. However, the effect of a-tDCS on between-character crowding is yet to be determined.

19.
Pediatr Emerg Care ; 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38713845

RESUMEN

BACKGROUND: A removable brace with home management is widely accepted treatment for distal radius buckle fractures, which most commonly involve the dorsal cortex. PURPOSE: The purpose of this study is to determine if a removable brace and home management treatment is safe for volar distal radius buckle fractures. MATERIALS AND METHODS: Isolated distal radius buckle fractures in children (3-16 years) diagnosed at an acute care visit (April 1, 2019 to May 31, 2022) were identified. Final diagnosis was confirmed using strict criteria including cortical buckling without cortical breach or physeal involvement. Cortical buckling was categorized as either dorsal or volar. Demographic data, mechanism of injury, treatment, and any complications were recorded and analyzed. RESULTS: Three hundred thirty-three fractures were either dorsal (254, 76%) or volar (79, 24%) buckle fractures. Mean age (SD) for volar fractures (9.3 [2.2 years]; range, 4-14 years) was significantly higher than for dorsal fractures (8.5 (3.0 years); range, 3-15 years; P = 0.012). More girls had volar fractures (48 [60%], P = 0.006). Most fractures occurred after a standing-height fall. Two hundred forty-four (96%) dorsal and 76 (96%) volar fractures were initially treated with a removable brace. Two hundred fourteen (84%) dorsal and 66 (84%) volar fractures had orthopedic follow-up. Brace treatment continued for 167 (167/204, 82%) dorsal and 56 (56/63, 89%) volar fractures. Treatment changed from initial brace to cast for 37 (37/204, 18%) dorsal fractures and 7 (7/63, 11%) volar fractures, influenced by caregiver preference and/or sport participation requirements. Only 1 (1/79, 1%) patient with a volar fracture returned for an additional visit for persistent pain. CONCLUSIONS: When diagnosis of volar buckle fracture is made using the same strict criteria used for dorsal buckle fractures, removable brace and home management treatment is safe. Shared decision making with caregivers may alter buckle fracture treatment.

20.
Nature ; 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38719964
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