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1.
Neurocrit Care ; 40(2): 795-806, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37308729

RESUMO

Traumatic brain injury is a leading cause of death and disability worldwide. Interventions that mitigate secondary brain injury have the potential to improve outcomes for patients and reduce the impact on communities and society. Increased circulating catecholamines are associated with worse outcomes and there are supportive animal data and indications in human studies of benefit from beta-blockade after severe traumatic brain injury. Here, we present the protocol for a dose-finding study using esmolol in adults commenced within 24 h of severe traumatic brain injury. Esmolol has practical advantages and theoretical benefits as a neuroprotective agent in this setting, but these must be balanced against the known risk of secondary injury from hypotension. The aim of this study is to determine a dose schedule for esmolol, using the continual reassessment method, that combines a clinically significant reduction in heart rate as a surrogate for catecholamine drive with maintenance of cerebral perfusion pressure. The maximum tolerated dosing schedule for esmolol can then be tested for patient benefit in subsequent randomized controlled trials.Trial registration ISRCTN, ISRCTN11038397, registered retrospectively 07/01/2021 https://www.isrctn.com/ISRCTN11038397.


Assuntos
Lesões Encefálicas Traumáticas , Propanolaminas , Adulto , Humanos , Estudos Retrospectivos , Propanolaminas/farmacologia , Propanolaminas/uso terapêutico , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/tratamento farmacológico , Administração Intravenosa , Ensaios Clínicos Fase II como Assunto
2.
Neurocrit Care ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38951446

RESUMO

BACKGROUND: Targeted beta-blockade after severe traumatic brain injury may reduce secondary brain injury by attenuating the sympathoadrenal response. The potential role and optimal dosage for esmolol, a selective, short-acting, titratable beta-1 beta-blocker, as a safe, putative early therapy after major traumatic brain injury has not been assessed. METHODS: We conducted a single-center, open-label dose-finding study using an adaptive model-based design. Adults (18 years or older) with severe traumatic brain injury and intracranial pressure monitoring received esmolol within 24 h of injury to reduce their heart rate by 15% from baseline of the preceding 4 h while ensuring cerebral perfusion pressure was maintained above 60 mm Hg. In cohorts of three, the starting dosage and dosage increments were escalated according to a prespecified plan in the absence of dose-limiting toxicity. Dose-limiting toxicity was defined as failure to maintain cerebral perfusion pressure, triggering cessation of esmolol infusion. The primary outcome was the maximum tolerated dosage schedule of esmolol, defined as that associated with less than 10% probability of dose-limiting toxicity. Secondary outcomes include 6-month mortality and 6-month extended Glasgow Outcome Scale score. RESULTS: Sixteen patients (6 [37.5%] female patients; mean age 36 years [standard deviation 13 years]) with a median Glasgow Coma Scale score of 6.5 (interquartile range 5-7) received esmolol. The optimal starting dosage of esmolol was 10 µg/kg/min, with increments every 30 min of 5 µg/kg/min, as it was the highest dosage with less than 10% estimated probability of dose-limiting toxicity (7%). All-cause mortality was 12.5% at 6 months (corresponding to a standardized mortality ratio of 0.63). One dose-limiting toxicity event and no serious adverse hemodynamic effects were seen. CONCLUSIONS: Esmolol administration, titrated to a heart rate reduction of 15%, is feasible within 24 h of severe traumatic brain injury. The probability of dose-limiting toxicity requiring withdrawal of esmolol when using the optimized schedule is low. Trial registrationI SRCTN, ISRCTN11038397, registered retrospectively January 7, 2021 ( https://www.isrctn.com/ISRCTN11038397 ).

3.
Nanotechnology ; 33(3)2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34624877

RESUMO

The 1T/2H hybridized and 2H pure phases of MoS2nanoflowers were synthesized in a one-step hydrothermal process with the molybdenum source as sodium molybdate dihydrate and the sulfur source as thiourea. The as-prepared 1T/2H hybridized and 2H pure phases of MoS2were investigated using a thermogravimetry\differential thermal analysis, powder x-ray diffraction, field emission scanning electron microscopy, and energy-dispersive x-ray spectroscopy. The obtained 1T/2H hybridized phases of MoS2were confirmed by the Raman spectroscopy. The electrochemical characteristics of MoS2electrodes were examined using cycle voltammetry, galvanostatic charge-discharge and electrochemical impedance spectroscopy. The electrodes are based on the 1T/2H hybridized phases MoS2with specific capacitance (Cp) of 555.4 F g-1at current densities (Cd) of 0.5 A g-1, capacity retention ratio of 85% after 10 000 cycles were observed that could be a strong potential electrode material for supercapacitors application.

4.
Neurocrit Care ; 33(2): 508-515, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-31993953

RESUMO

BACKGROUND/OBJECTIVE: Sympathetic nervous system activation after aneurysmal subarachnoid hemorrhage (aSAH) is associated with complications and poor outcome. In this systematic review and meta-analysis, we investigate the effect of beta-blockers on outcome after aSAH. METHODS: The review was prospectively registered with PROSPERO (CRD42019111784). We performed a systematic literature search of MEDLINE, EMBASE, the Cochrane Library, published conference proceedings, and abstracts. Eligible studies included both randomized controlled trials and observational studies up to October 2018, reporting the effect of beta-blocker therapy on the following outcomes in aSAH: mortality, vasospasm, delayed cerebral ischemia, infarction or stroke, cardiac dysfunction, and functional outcomes. Studies involving traumatic SAH were excluded. Citations were reviewed, and data extracted independently by two investigators using a standardized proforma. RESULTS: We identified 819 records with 16 studies (four were randomized controlled trials) including 6702 patients selected for analysis. Exposure to beta-blockade either before or after aSAH was associated with a significant reduction in unadjusted mortality (RR 0.63, 95% CI 0.42-0.93, p = 0.02). A significant reduction in unadjusted mortality was also seen in prospective trials of post-event beta-blockade (RR 0.51, 95% CI 0.28-0.93, p = 0.03). Statistically significant differences were not seen for other outcomes investigated. CONCLUSIONS: In adult patients with aSAH, beta-blocker therapy is associated with a mortality benefit. Studies are generally of a low quality with considerable clinical heterogeneity. Prospective large interventional trials with patient centered outcomes are required to validate this finding.


Assuntos
Isquemia Encefálica , Cardiopatias , Hemorragia Subaracnóidea , Vasoespasmo Intracraniano , Antagonistas Adrenérgicos beta/farmacologia , Adulto , Humanos , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/tratamento farmacológico , Resultado do Tratamento
5.
Lancet ; 384(9942): 504-13, 2014 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-24794816

RESUMO

BACKGROUND: Friedreich's ataxia is a progressive degenerative disorder caused by deficiency of the frataxin protein. Expanded GAA repeats within intron 1 of the frataxin (FXN) gene lead to its heterochromatinisation and transcriptional silencing. Preclinical studies have shown that the histone deacetylase inhibitor nicotinamide (vitamin B3) can remodel the pathological heterochromatin and upregulate expression of FXN. We aimed to assess the epigenetic and neurological effects and safety of high-dose nicotinamide in patients with Friedreich's ataxia. METHODS: In this exploratory, open-label, dose-escalation study in the UK, male and female patients (aged 18 years or older) with Friedreich's ataxia were given single doses (phase 1) and repeated daily doses of 2-8 g oral nicotinamide for 5 days (phase 2) and 8 weeks (phase 3). Doses were gradually escalated during phases 1 and 2, with individual maximum tolerated doses used in phase 3. The primary outcome was the upregulation of frataxin expression. We also assessed the safety and tolerability of nicotinamide, used chromatin immunoprecipitation to investigate changes in chromatin structure at the FXN gene locus, and assessed the effect of nicotinamide treatment on clinical scales for ataxia. This study is registered with ClinicalTrials.gov, number NCT01589809. FINDINGS: Nicotinamide was generally well tolerated; the main adverse event was nausea, which in most cases was mild, dose-related, and resolved spontaneously or after dose reduction, use of antinausea drugs, or both. Phase 1 showed a dose-response relation for proportional change in frataxin protein concentration from baseline to 8 h post-dose, which increased with increasing dose (p=0·0004). Bayesian analysis predicted that 3·8 g would result in a 1·5-times increase and 7·5 g in a doubling of frataxin protein concentration. Phases 2 and 3 showed that daily dosing at 3·5-6 g resulted in a sustained and significant (p<0·0001) upregulation of frataxin expression, which was accompanied by a reduction in heterochromatin modifications at the FXN locus. Clinical measures showed no significant changes. INTERPRETATION: Nicotinamide was associated with a sustained improvement in frataxin concentrations towards those seen in asymptomatic carriers during 8 weeks of daily dosing. Further investigation of the long-term clinical benefits of nicotinamide and its ability to ameliorate frataxin deficiency in Friedreich's ataxia is warranted. FUNDING: Ataxia UK, Ataxia Ireland, Association Suisse de l'Ataxie de Friedreich, Associazione Italiana per le Sindromi Atassiche, UK National Institute for Health Research, European Friedreich's Ataxia Consortium for Translational Studies, and Imperial Biomedical Research Centre.


Assuntos
Ataxia de Friedreich/tratamento farmacológico , Proteínas de Ligação ao Ferro/efeitos dos fármacos , Niacinamida/administração & dosagem , Complexo Vitamínico B/administração & dosagem , Adulto , Cromatina/efeitos dos fármacos , Cromatina/genética , Relação Dose-Resposta a Droga , Epigênese Genética , Feminino , Ataxia de Friedreich/genética , Humanos , Proteínas de Ligação ao Ferro/biossíntese , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Reino Unido , Adulto Jovem , Frataxina
7.
J Neurol Neurosurg Psychiatry ; 85(3): 331-8, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23486992

RESUMO

OBJECTIVE: Titin gene (TTN) mutations have been described in eight families with hereditary myopathy with early respiratory failure (HMERF). Some of the original patients had features resembling myofibrillar myopathy (MFM), arguing that TTN mutations could be a much more common cause of inherited muscle disease, especially in presence of early respiratory involvement. METHODS: We studied 127 undiagnosed patients with clinical presentation compatible with MFM. Sanger sequencing for the two previously described TTN mutations in HMERF (p.C30071R in the 119th fibronectin-3 (FN3) domain, and p.R32450W in the kinase domain) was performed in all patients. Patients with mutations had detailed review of their clinical records, muscle MRI findings and muscle pathology. RESULTS: We identified five new families with the p.C30071R mutation who were clinically similar to previously reported cases, and muscle pathology demonstrated diagnostic features of MFM. Two further families had novel variants in the 119th FN3 domain (p.P30091L and p.N30145K). No patients were identified with mutations at position p.32450. CONCLUSIONS: Mutations in TTN are a cause of MFM, and titinopathy is more common than previously thought. The finding of the p.C30071R mutation in 3.9% of our study population is likely due to a British founder effect. The occurrence of novel FN3 domain variants, although still of uncertain pathogenicity, suggests that other mutations in this domain may cause MFM, and that the disease is likely to be globally distributed. We suggest that HMERF due to mutations in the TTN gene be nosologically classified as MFM-titinopathy.


Assuntos
Conectina/genética , Efeito Fundador , Doenças Genéticas Inatas/genética , Doenças Musculares/genética , Insuficiência Respiratória/genética , Adulto , Idoso , Feminino , Doenças Genéticas Inatas/patologia , Haplótipos , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/patologia , Doenças Musculares/patologia , Mutação , Linhagem , Reação em Cadeia da Polimerase , Insuficiência Respiratória/patologia
8.
J Intensive Care Soc ; 25(2): 164-170, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38737309

RESUMO

Background: Fragility analysis supplements the p-value and risk of bias assessment in the interpretation of results of randomised controlled trials. In this systematic review we determine the fragility index (FI) and fragility quotient (FQ) of randomised trials in aneurysmal subarachnoid haemorrhage. Methods: This is a systematic review registered with PROSPERO (ID: CRD42020173604). Randomised controlled trials in adults with aneurysmal subarachnoid haemorrhage were analysed if they reported a statistically significant primary outcome of mortality, function (e.g. modified Rankin Scale), vasospasm or delayed neurological deterioration. Results: We identified 4825 records with 18 randomised trials selected for analysis. The median fragility index was 2.5 (inter-quartile range 0.25-5) and the median fragility quotient was 0.015 (IQR 0.02-0.039). Five of 20 trial outcomes (25%) had a fragility index of 0. In seven trials (39.0%), the number of participants lost to follow-up was greater than or equal to the fragility index. Only 16.7% of trials are at low risk of bias. Conclusion: Randomised controlled trial evidence supporting management of aneurysmal subarachnoid haemorrhage is weaker than indicated by conventional analysis using p-values alone. Increased use of fragility analysis by clinicians and researchers could improve the translation of evidence to practice.

9.
Cephalalgia ; 32(6): 473-80, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22492423

RESUMO

AIMS: The underlying mechanisms of migraine remain poorly understood, partly because we lack objective methods for quantitative analysis of neurological function. To address this issue, we measured interictal saccadic latency in migraineurs and controls. METHODS: In a cross-sectional study, we compared interictal saccadic latency distributions of 12,800 saccades in 32 migraineurs with 32 age- and sex-matched controls. RESULTS: The variability of migraineurs' reaction time distributions was significantly smaller (σ = 1.01 vs. 1.13; p < 0.05) compared with controls. In addition, a smaller proportion of migraineurs generated 'early' saccades (31% vs. 56%: p < 0.05). Sensitivity/specificity analysis demonstrated the potential benefit of this technique to diagnostic discrimination. CONCLUSIONS: The migraineur's brain behaves significantly differently from that of a control during the interictal period. By analysing whole distributions, rather than just means, data can be related directly to current neurophysiological models: specifically, the observed decrease in variability suggests a functional deficit in the noradrenergic systems influencing the cerebral cortex. From a clinical perspective, this novel method of characterising neurological function in migraine is more rapid, practicable, inexpensive, objective and quantitative than previous methods such as evoked potentials and transcranial magnetic stimulation, and has the potential both to improve current diagnostic discrimination and to help guide future research into the underlying neural mechanisms.


Assuntos
Transtornos de Enxaqueca/diagnóstico , Transtornos de Enxaqueca/fisiopatologia , Movimentos Sacádicos/fisiologia , Adolescente , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tempo de Reação , Sensibilidade e Especificidade , Adulto Jovem
10.
BMC Res Notes ; 15(1): 202, 2022 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-35690875

RESUMO

OBJECTIVE: To narratively describe the challenges and solutions required in delivering a non-commercial study of children undergoing cardiac surgery using a novel subcutaneous hormone collection device. RESULTS: The challenges faced by the research team are divided into those of conducting healthcare research in children and those specific to this study. Many of the issues of conducting healthcare research in children can and have been overcome by structural and institutional culture change-normalising and embedding research as part of good clinical care. The issues specific to insertion and maintenance of the novel collection device can be overcome by education and support of the clinical teams. The increased incentives and resources of commercial research may have overcome many of these.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Criança , Humanos , Recém-Nascido
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