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1.
Neuroradiology ; 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38717474

RESUMEN

PURPOSE: Morning glory disc anomaly (MGDA) is a rare congenital ophthalmologic disorder. Historically it has been diagnosed fundoscopically, with little in the literature regarding its imaging findings. The purpose of this study is to further characterize the orbital and associated intracranial magnetic resonance imaging (MRI) findings of MGDA in our tertiary pediatric center. METHODS: A retrospective review was performed of fundoscopically-diagnosed cases of MGDA, that had been referred for MRI. All MRI studies were scrutinized for orbital and other intracranial abnormalities known to occur in association with MGDA. RESULTS: 18 of 19 cases of MGDA showed three characteristic MRI findings: funnel-shaped morphology of the posterior optic disc, abnormal soft tissue associated with the retrobulbar optic nerve, and effacement of adjacent subarachnoid spaces. The ipsilateral (intraorbital) optic nerve was larger in one patient and smaller in six. The ipsilateral optic chiasm was larger in two patients and smaller in one. CONCLUSION: This study represents a comprehensive radiological-led investigation into MGDA. It describes the most frequently-encountered MRI findings in MGDA and emphasizes the importance of MRI in this cohort, i.e., in distinguishing MGDA from other posterior globe abnormalities, in assessing the visual pathway, and in screening for associated intracranial abnormalities - skull base/cerebral, vascular, and facial. It hypothesizes neurocristopathy as an underlying cause of MGDA and its associations. Caliber abnormalities of the ipsilateral optic nerve and chiasm are a frequent finding in MGDA. Optic pathway enlargement should not be labeled "glioma". (239/250).

2.
Top Stroke Rehabil ; : 1-10, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38598484

RESUMEN

BACKGROUND: Post-stroke lateropulsion is prevalent and has been associated with varied lesion locations, but existing imaging studies are limited by small participant cohorts. Evidence to guide lateropulsion rehabilitation is also limited. Improved understanding of lesion localization associated with lateropulsion post-stroke may inform more targeted intervention approaches. OBJECTIVES: This study investigated the associations between stroke neuroimaging data and presence of lateropulsion at inpatient rehabilitation admission. METHODS: This prospective, observational study included participants aged ≥65 years, admitted for inpatient stroke rehabilitation. Using routinely collected clinical neuroimaging data, stroke type, location, and volume were reported, and their association with lateropulsion presence (Four-Point Pusher Score - 4PPS) at admission was explored. RESULTS: Of 144 included participants, 82 (56.9%) had lateropulsion (4PPS ≥1). Lateropulsion presence was univariately associated with hemorrhagic stroke (p = 0.002), frontal cortical involvement (OR = 2.17, 95%CI 1.02-6.46), and white matter involvement (OR = 2.45, 95%CI 1.24-4.85), particularly frontal white matter (p = 0.021). Lesions involving the posterior limb of the internal capsule (OR = 2.88, 95% CI 1.14-7.27) and those involving the entire thalamus (OR = 1.0, p = 0.03) were associated with lateropulsion presence. When stratified by stroke type, no specific location was significantly associated with lateropulsion presence in hemorrhagic strokes. Among participants with ischemic stroke, involvement of the pre-central gyrus (OR = 2.45, 95%CI 1.05-5.76), post-central gyrus (OR = 2.76, 95%CI 1.15-6.60), inferior parietal cortex (OR = 3.95, 95%CI 1.43-10.90), and supramarginal gyrus (OR = 3.73, 95%CI 1.25-11.13) were associated with lateropulsion presence. The stroke laterality and size were not significantly associated with lateropulsion presence. CONCLUSIONS: The findings indicate a role of network disconnection in the post-stroke lateropulsion presence. Future, larger-cohort lesion-network mapping studies are recommended.

3.
Top Stroke Rehabil ; : 1-12, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38526999

RESUMEN

BACKGROUND: Post-stroke lateropulsion is prevalent and associated with poor rehabilitation outcomes; however, data regarding long-term function associated with lateropulsion are lacking. OBJECTIVES: This study aimed to explore lateropulsion resolution and associations between lateropulsion, functional outcomes, and fall occurrence up to 12 months post-stroke. METHODS: Participants for this prospective, longitudinal cohort study were recruited from a Stroke Rehabilitation Unit (SRU). Assessments were conducted at SRU admission, at discharge, and at three, six, nine, and twelve months post-stroke. Outcomes included the Four-Point Pusher Score (4PPS), Functional Independence Measure (FIM), and fall occurrence. Longitudinal outcomes were modeled using generalized linear mixed-effects models. RESULTS: The final analyses included data from 144 participants. Eighty-two participants (56.9) had lateropulsion (4PPS ≥ 1) on admission. Odds of resolved lateropulsion (4PPS = 0) increased longitudinally from discharge for people who participated in rehabilitation physiotherapy (OR: 9.7, 28.1, 43.1, 81.3: <0.001 at three, six, nine, and twelve months respectively). The greatest FIM improvement among participants in all 4PPS categories occurred during the SRU inpatient phase. The probability of falls post-discharge was greatest among participants with 4PPS = 1 at three months, when compared with 4PPS = 0 (p= 0.022). CONCLUSIONS: This study showed that lateropulsion can continue to resolve up to one year post-stroke. Earlier lateropulsion resolution was associated with ongoing rehabilitation physiotherapy participation. Long-term functional gains were maintained among people discharged home, whereas functional status deteriorated after six months among those in residential care. Study findings will allow rehabilitation and service providers to better plan for and accommodate the long-term rehabilitation and care needs of people with post-stroke lateropulsion.

4.
Artículo en Inglés | MEDLINE | ID: mdl-38453632

RESUMEN

OBJECTIVES: People may experience a myriad of symptoms after mild traumatic brain injury (mTBI), but the relationship between symptoms and objective assessments is poorly characterized. This study sought to investigate the association between symptoms, resting heart rate (HR), and exercise tolerance in individuals following mTBI, with a secondary aim to examine the relationship between symptom-based clinical profiles and recovery. METHODS: Prospective observational study of adults aged 18 to 65 years who had sustained mTBI within the previous 7 days. Symptoms were assessed using the Post-Concussion Symptom Scale, HR was measured at rest, and exercise tolerance was assessed using the Buffalo Concussion Bike Test. Symptom burden and symptom-based clinical profiles were examined with respect to exercise tolerance and resting HR. RESULTS: Data from 32 participants were assessed (mean age 36.5 ± 12.6 years, 41% female, 5.7 ± 1.1 days since injury). Symptom burden (number of symptoms and symptom severity) was significantly associated with exercise intolerance (P = .002 and P = .025, respectively). Physiological and vestibular-ocular clinical profile composite groups were associated with exercise tolerance (P = .001 and P = .014, respectively), with individuals who were exercise intolerant having a higher mean number of symptoms in each profile than those who were exercise tolerant. Mood-related and autonomic clinical profiles were associated with a higher resting HR (>80 bpm) (P = .048 and P = .028, respectively), suggesting altered autonomic response for participants with symptoms relating to this profile. After adjusting for age and mechanism of injury (sports- or non-sports-related), having a higher mood-related clinical profile was associated with persisting symptoms at 3 months postinjury (adjusted odds ratio = 2.08; 95% CI, 1.11-3.90; P = .013). CONCLUSION: Symptom-based clinical profiles, in conjunction with objective measures such as resting HR and exercise tolerance, are important components of clinical care for those having sustained mTBI. These results provide preliminary support for the concept that specific symptoms are indicative of autonomic dysfunction following mTBI.

5.
Childs Nerv Syst ; 39(4): 857-861, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36658366

RESUMEN

Although the posterior fossa is a common location for paediatric brain tumours [1], diffuse glioma isolated to the cerebellum is an extremely rare imaging entity. Only two cases of isolated diffuse paediatric cerebellar glioma have been reported in the English language to the best of our knowledge [2, 3], and only one of these cases had a similar imaging phenotype to our cases [3]. Although somewhat similar to Lhermitte-Duclos (dysplastic gangliocytoma of the cerebellum), the appearances are distinct from other neoplastic entities of the paediatric posterior fossa. Clinical presentation and neurological examination findings are vital however to help differentiate other diffuse pathologies involving the cerebellum such as rhombencephalitis. Presented here are two diffuse cerebellar gliomas in children under the age of 3 with near identical imaging phenotypes demonstrating differing histological and molecular genetic profiles.


Asunto(s)
Neoplasias Encefálicas , Neoplasias Cerebelosas , Glioma , Síndrome de Hamartoma Múltiple , Humanos , Neoplasias Cerebelosas/diagnóstico por imagen , Neoplasias Cerebelosas/genética , Imagen por Resonancia Magnética , Cerebelo/diagnóstico por imagen , Glioma/diagnóstico por imagen , Glioma/genética , Glioma/patología , Neoplasias Encefálicas/patología , Síndrome de Hamartoma Múltiple/genética , Síndrome de Hamartoma Múltiple/patología , Síndrome de Hamartoma Múltiple/cirugía
6.
BMJ Open ; 12(2): e058826, 2022 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-35190446

RESUMEN

INTRODUCTION: Preclinical, clinical and epidemiological studies support the hypothesis that aberrant systemic metabolism of amyloid beta (Aß) in the peripheral circulation is causally related to the development of Alzheimer's disease (AD). Specifically, recent studies suggest that increased plasma concentrations of lipoprotein-Aß compromise the brain microvasculature, resulting in extravasation and retention of the lipoprotein-Aß moiety. The latter results in an inflammatory response and neurodegeneration ensues. Probucol, a historic cholesterol-lowering drug, has been shown in murine models to suppress lipoprotein-Aß secretion, concomitant with maintaining blood-brain-barrier function, suppressing neurovascular inflammation and supporting cognitive function. This protocol details the probucol in Alzheimer's study, a drug intervention trial investigating if probucol has potential to attenuate cognitive decline, delay brain atrophy and reduce cerebral amyloid burden in patients with mild-to-moderate AD. METHODS AND ANALYSIS: The study is a phase II, randomised, placebo-controlled, double-blind single-site clinical trial held in Perth, Australia. The target sample is 314 participants with mild-to-moderate AD. Participants will be recruited and randomised (1:1) to a 104-week intervention consisting of placebo induction for 2 weeks followed by 102 weeks of probucol (Lorelco) or placebo. The primary outcome is changed in cognitive performance determined via the Alzheimer's Disease Assessment Scales-Cognitive Subscale test between baseline and 104 weeks. Secondary outcomes measures will be the change in brain structure and function, cerebral amyloid load, quality of life, and the safety and tolerability of Lorelco, after a 104week intervention. ETHICS AND DISSEMINATION: The study has been approved by the Bellberry Limited Human Research Ethics Committee (approval number: HREC2019-11-1063; Version 4, 6 October 2021). Informed consent will be obtained from participants prior to any study procedures being performed. The investigator group will disseminate study findings through peer-reviewed publications, key conferences and local stakeholder events. TRIAL REGISTRATION NUMBER: Australian New Zealand Clinical Trials Registry (ACTRN12621000726853).


Asunto(s)
Enfermedad de Alzheimer , Probucol , Péptidos beta-Amiloides/metabolismo , Animales , Australia , Ensayos Clínicos Fase II como Asunto , Cognición , Método Doble Ciego , Humanos , Ratones , Probucol/farmacología , Probucol/uso terapéutico , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
7.
BJR Case Rep ; 8(1): 20210105, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-35136641

RESUMEN

Hirayama disease is a rare cervical myelopathy characterised by asymmetrical upper limb weakness and muscle atrophy in the forearm and hand. MRI of the cervical spine plays an essential role in diagnosis, however, the characteristic findings are often only seen when the patient is imaged with the neck in flexion. We present a case of a 15-year-old male who presented with left forearm and hand weakness with muscle wasting. An MRI of the cervical spine with the neck in a neutral position demonstrated atrophy of the spinal cord with intrinsic signal abnormality between C5 and C7. Further imaging with the patient's neck in flexion demonstrated the hallmark features of Hirayama disease. There was anterior displacement of the thecal sac and spinal cord, and an enlarged, crescent-shaped dorsal epidural space which enhanced following i.v. gadolinium administration. The atrophic segment of cord contacted the posterior vertebral bodies when the neck was in full flexion. This case highlights the importance of imaging patients suspected of having this entity with the neck in full flexion in order to make a diagnosis.

8.
PLoS Biol ; 19(9): e3001358, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34520451

RESUMEN

Several lines of study suggest that peripheral metabolism of amyloid beta (Aß) is associated with risk for Alzheimer disease (AD). In blood, greater than 90% of Aß is complexed as an apolipoprotein, raising the possibility of a lipoprotein-mediated axis for AD risk. In this study, we report that genetic modification of C57BL/6J mice engineered to synthesise human Aß only in liver (hepatocyte-specific human amyloid (HSHA) strain) has marked neurodegeneration concomitant with capillary dysfunction, parenchymal extravasation of lipoprotein-Aß, and neurovascular inflammation. Moreover, the HSHA mice showed impaired performance in the passive avoidance test, suggesting impairment in hippocampal-dependent learning. Transmission electron microscopy shows marked neurovascular disruption in HSHA mice. This study provides causal evidence of a lipoprotein-Aß /capillary axis for onset and progression of a neurodegenerative process.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides/biosíntesis , Hepatocitos/metabolismo , Péptidos beta-Amiloides/genética , Animales , Barrera Hematoencefálica/patología , Encéfalo/irrigación sanguínea , Capilares/patología , Modelos Animales de Enfermedad , Humanos , Inflamación , Aprendizaje , Lipoproteínas/metabolismo , Masculino , Ratones Transgénicos , Degeneración Nerviosa
9.
Neuroscience ; 467: 218-236, 2021 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-34087394

RESUMEN

Traumatic brain injury (TBI) is a common but heterogeneous injury underpinned by numerous complex and interrelated pathophysiological mechanisms. An essential trace element, iron is abundant within the brain and involved in many fundamental neurobiological processes, including oxygen transportation, oxidative phosphorylation, myelin production and maintenance, as well as neurotransmitter synthesis and metabolism. Excessive levels of iron are neurotoxic and thus iron homeostasis is tightly regulated in the brain, however, many details about the mechanisms by which this is achieved are yet to be elucidated. A key mediator of oxidative stress, mitochondrial dysfunction and neuroinflammatory response, iron dysregulation is an important contributor to secondary injury in TBI. Advances in neuroimaging that leverage magnetic susceptibility properties have enabled increasingly comprehensive investigations into the distribution and behaviour of iron in the brain amongst healthy individuals as well as disease states such as TBI. Quantitative Susceptibility Mapping (QSM) is an advanced neuroimaging technique that promises quantitative estimation of local magnetic susceptibility at the voxel level. In this review, we provide an overview of brain iron and its homeostasis, describe recent advances enabling applications of QSM within the context of TBI and summarise the current state of the literature. Although limited, the emergent research suggests that QSM is a promising neuroimaging technique that can be used to investigate a host of pathophysiological changes that are associated with TBI.


Asunto(s)
Lesiones Traumáticas del Encéfalo , Imagen por Resonancia Magnética , Encéfalo/diagnóstico por imagen , Lesiones Traumáticas del Encéfalo/diagnóstico por imagen , Mapeo Encefálico , Humanos , Hierro , Neuroimagen
10.
BMJ Open ; 11(5): e046460, 2021 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-33986061

RESUMEN

INTRODUCTION: Mild traumatic brain injury (mTBI) is a complex injury with heterogeneous physical, cognitive, emotional and functional outcomes. Many who sustain mTBI recover within 2 weeks of injury; however, approximately 10%-20% of individuals experience mTBI symptoms beyond this 'typical' recovery timeframe, known as persistent post-concussion symptoms (PPCS). Despite increasing interest in PPCS, uncertainty remains regarding its prevalence in community-based populations and the extent to which poor recovery may be identified using early predictive markers. OBJECTIVE: (1) Establish a research dataset of people who have experienced mTBI and document their recovery trajectories; (2) Evaluate a broad range of novel and established prognostic factors for inclusion in a predictive model for PPCS. METHODS AND ANALYSIS: The Concussion Recovery Study (CREST) is a prospective, longitudinal observational cohort study conducted in Perth, Western Australia. CREST is recruiting adults aged 18-65 from medical and community-based settings with acute diagnosis of mTBI. CREST will create a state-wide research dataset of mTBI cases, with data being collected in two phases. Phase I collates data on demographics, medical background, lifestyle habits, nature of injury and acute mTBI symptomatology. In Phase II, participants undergo neuropsychological evaluation, exercise tolerance and vestibular/ocular motor screening, MRI, quantitative electroencephalography and blood-based biomarker assessment. Follow-up is conducted via telephone interview at 1, 3, 6 and 12 months after injury. Primary outcome measures are presence of PPCS and quality of life, as measured by the Post-Concussion Symptom Scale and the Quality of Life after Brain Injury questionnaires, respectively. Multivariate modelling will examine the prognostic value of promising factors. ETHICS AND DISSEMINATION: Human Research Ethics Committees of Royal Perth Hospital (#RGS0000003024), Curtin University (HRE2019-0209), Ramsay Health Care (#2009) and St John of God Health Care (#1628) have approved this study protocol. Findings will be published in peer-reviewed journals and presented at scientific conferences. TRIAL REGISTRATION NUMBER: ACTRN12619001226190.


Asunto(s)
Conmoción Encefálica , Síndrome Posconmocional , Adulto , Conmoción Encefálica/diagnóstico , Estudios de Cohortes , Humanos , Estudios Observacionales como Asunto , Síndrome Posconmocional/diagnóstico , Estudios Prospectivos , Calidad de Vida , Australia Occidental
11.
Neurochem Res ; 46(5): 1166-1176, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33523394

RESUMEN

Poly-arginine peptides R18 and R18D have previously been demonstrated to be neuroprotective in ischaemic stroke models. Here we examined the proteolytic stability and efficacy of R18 and R18D in reducing infarct core growth and preserving the ischaemic penumbra following middle cerebral artery occlusion (MCAO) in the Sprague Dawley rat. R18 (300 or 1000 nmol/kg), R18D (300 nmol/kg) or saline were administered intravenously 10 min after MCAO induced using a filament. Serial perfusion and diffusion-weighted MRI imaging was performed to measure changes in the infarct core and penumbra from time points between 45- and 225-min post-occlusion. Repeated measures analyses of infarct growth and penumbral tissue size were evaluated using generalised linear mixed models (GLMMs). R18D (300 nmol/kg) was most effective in slowing infarct core growth (46.8 mm3 reduction; p < 0.001) and preserving penumbral tissue (21.6% increase; p < 0.001), followed by R18 at the 300 nmol/kg dose (core: 29.5 mm3 reduction; p < 0.001, penumbra: 12.5% increase; p < 0.001). R18 at the 1000 nmol/kg dose had a significant impact in slowing core growth (19.5 mm3 reduction; p = 0.026), but only a modest impact on penumbral preservation (6.9% increase; p = 0.062). The in vitro anti-excitotoxic neuroprotective efficacy of R18D was also demonstrated to be unaffected when preincubated for 1-3 h or overnight, in a cell lysate prepared from dying neurons or with the proteolytic enzyme, plasmin, whereas the neuroprotective efficacy of R18 was significantly reduced after a 2-h incubation. These findings highlight the capacity of poly-arginine peptides to reduce infarct growth and preserve the ischaemic penumbra, and confirm the superior efficacy and proteolytic stability of R18D, which indicates that this peptide is likely to retain its neuroprotective properties when co-administered with alteplase during thrombolysis for acute ischaemic stroke.


Asunto(s)
Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Fármacos Neuroprotectores/uso terapéutico , Péptidos/uso terapéutico , Animales , Encéfalo/efectos de los fármacos , Células Cultivadas , Fibrinolisina/metabolismo , Masculino , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/metabolismo , Péptidos/química , Péptidos/metabolismo , Estabilidad Proteica , Ratas Sprague-Dawley , Estereoisomerismo
12.
Brain Sci ; 10(1)2020 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-31906443

RESUMEN

BACKGROUND: Persisting post-concussion symptoms (PPCS) is a complex, multifaceted condition in which individuals continue to experience the symptoms of mild traumatic brain injury (mTBI; concussion) beyond the timeframe that it typically takes to recover. Currently, there is no way of knowing which individuals may develop this condition. METHOD: Patients presenting to a hospital emergency department (ED) within 48 h of sustaining a mTBI underwent neuropsychological assessment and demographic, injury-related information and blood samples were collected. Concentrations of blood-based biomarkers neuron specific enolase, neurofilament protein-light, and glial fibrillary acidic protein were assessed, and a subset of patients also underwent diffusion tensor-magnetic resonance imaging; both relative to healthy controls. Individuals were classified as having PPCS if they reported a score of 25 or higher on the Rivermead Postconcussion Symptoms Questionnaire at ~28 days post-injury. Univariate exact logistic regression was performed to identify measures that may be predictive of PPCS. Neuroimaging data were examined for differences in fractional anisotropy (FA) and mean diffusivity in regions of interest. RESULTS: Of n = 36 individuals, three (8.33%) were classified as having PPCS. Increased performance on the Repeatable Battery for the Assessment of Neuropsychological Status Update Total Score (OR = 0.81, 95% CI: 0.61-0.95, p = 0.004), Immediate Memory (OR = 0.79, 95% CI: 0.56-0.94, p = 0.001), and Attention (OR = 0.86, 95% CI: 0.71-0.97, p = 0.007) indices, as well as faster completion of the Trails Making Test B (OR = 1.06, 95% CI: 1.00-1.12, p = 0.032) at ED presentation were associated with a statistically significant decreased odds of an individual being classified as having PPCS. There was no significant association between blood-based biomarkers and PPCS in this small sample, although glial fibrillary acidic protein (GFAP) was significantly increased in individuals with mTBI relative to healthy controls. Furthermore, relative to healthy age and sex-matched controls (n = 8), individuals with mTBI (n = 14) had higher levels of FA within the left inferior frontal occipital fasciculus (t (18.06) = -3.01, p = 0.008). CONCLUSION: Performance on neuropsychological measures may be useful for predicting PPCS, but further investigation is required to elucidate the utility of this and other potential predictors.

13.
BMC Pediatr ; 18(1): 252, 2018 07 31.
Artículo en Inglés | MEDLINE | ID: mdl-30064388

RESUMEN

BACKGROUND: Of children with hemiplegic cerebral palsy, 75% have impaired somatosensory function, which contributes to learned non-use of the affected upper limb. Currently, motor learning approaches are used to improve upper-limb motor skills in these children, but few studies have examined the effect of any intervention to ameliorate somatosensory impairments. Recently, Sense© training was piloted with a paediatric sample, seven children with hemiplegic cerebral palsy, demonstrating statistically and clinically significant change in limb position sense, goal performance and bimanual hand-use. This paper describes a protocol for a Randomised Controlled Trial of Sense© for Kids training, hypothesising that its receipt will improve somatosensory discrimination ability more than placebo (dose-matched Goal Directed Therapy via Home Program). Secondary hypotheses include that it will alter brain activation in somatosensory processing regions, white-matter characteristics of the thalamocortical tracts and improve bimanual function, activity and participation more than Goal Directed Training via Home Program. METHODS AND DESIGN: This is a single blind, randomised matched-pair, placebo-controlled trial. Participants will be aged 6-15 years with a confirmed description of hemiplegic cerebral palsy and somatosensory discrimination impairment, as measured by the sense©_assess Kids. Participants will be randomly allocated to receive 3h a week for 6 weeks of either Sense© for Kids or Goal Directed Therapy via Home Program. Children will be matched on age and severity of somatosensory discrimination impairment. The primary outcome will be somatosensory discrimination ability, measured by sense©_assess Kids score. Secondary outcomes will include degree of brain activation in response to a somatosensory task measured by functional MRI, changes in the white matter of the thalamocortical tract measured by diffusion MRI, bimanual motor function, activity and participation. DISCUSSION: This study will assess the efficacy of an intervention to increase somatosensory discrimination ability in children with cerebral palsy. It will explore clinically important questions about the efficacy of intervening in somatosensation impairment to improve bimanual motor function, compared with focusing on motor impairment directly, and whether focusing on motor impairment alone can affect somatosensory ability. TRIAL REGISTRATION: This trial is registered with the Australian New Zealand Clinical Trials Registry, registration number: ACTRN12618000348257. World Health Organisation universal trial number: U1111-1210-1726.


Asunto(s)
Parálisis Cerebral/rehabilitación , Hemiplejía/rehabilitación , Hipoestesia/terapia , Tacto , Adolescente , Parálisis Cerebral/complicaciones , Parálisis Cerebral/fisiopatología , Niño , Hemiplejía/fisiopatología , Humanos , Hipoestesia/etiología , Imagen por Resonancia Magnética , Proyectos de Investigación , Método Simple Ciego
14.
Intern Med J ; 48(2): 194-197, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29415360

RESUMEN

A case of metformin encephalopathy is presented in a patient on haemodialysis for end-stage diabetic renal failure. The patient presented with frequent falls and clinical signs of Parkinsonism, on a background of recent anorexia and significant weight loss. Magnetic resonance imaging showed bilateral, symmetrical abnormalities centred on the lentiform nuclei. Metformin was withheld and signs and symptoms quickly resolved. We hypothesise that metformin may cause thiamine deficiency in patients with end-stage renal failure resulting in a specific metabolic encephalopathy.


Asunto(s)
Encefalopatías/inducido químicamente , Encefalopatías/tratamiento farmacológico , Hipoglucemiantes/efectos adversos , Metformina/efectos adversos , Tiamina/uso terapéutico , Complejo Vitamínico B/uso terapéutico , Adulto , Encefalopatías/diagnóstico por imagen , Nefropatías Diabéticas/diagnóstico por imagen , Nefropatías Diabéticas/terapia , Femenino , Humanos
15.
Neurology ; 89(24): 2406-2412, 2017 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-29117957

RESUMEN

OBJECTIVE: The purpose of this study of sickle cell disease (SCD) was to determine whether arteriopathy, measurable as intracranial vessel signal loss on magnetic resonance angiography (MRA), was associated with low nocturnal hemoglobin oxygen saturation (SpO2) or hemolytic rate, measurable as reticulocytosis or unconjugated hyperbilirubinemia. METHODS: Ninety-five East London children with SCD without prior stroke had overnight pulse oximetry, of whom 47 (26 boys, 39 hemoglobin SS; mean age 9.1 ± 3.1 years) also had MRA, transcranial Doppler (TCD), steady-state hemoglobin, and reticulocytes within 34 months. Two radiologists blinded to the other data graded arteriopathy on MRA as 0 (none) or as increasing severity grades 1, 2, or 3. RESULTS: Grades 2 or 3 arteriopathy (n = 24; 2 with abnormal TCD) predicted stroke/TIA compared with grades 0 and 1 (log-rank χ2 [1, n = 47] = 8.1, p = 0.004). Mean overnight SpO2 correlated negatively with reticulocyte percentage (r = -0.387; p = 0.007). Despite no significant differences across the degrees of arteriopathy in genotype, mean overnight SpO2 was higher (p < 0.01) in those with grade 0 (97.0% ± 1.6%) than those with grades 2 (93.9 ± 3.7%) or 3 (93.5% ± 3.0%) arteriopathy. Unconjugated bilirubin was not associated but reticulocyte percentage was lower (p < 0.001) in those with grade 0 than those with grades 2 and 3 arteriopathy. In multivariable logistic regression, lower mean overnight SpO2 (odds ratio 0.50, 95% confidence interval 0.26-0.96; p < 0.01) predicted arteriopathy independent of reticulocyte percentage (odds ratio 1.47, 95% confidence interval 1.15-1.87; p = 0.003). CONCLUSION: Low nocturnal SpO2 and reticulocytosis are associated with intracranial arteriopathy in children with SCD. Preventative strategies might reduce stroke risk.


Asunto(s)
Anemia de Células Falciformes/metabolismo , Enfermedades Arteriales Cerebrales/diagnóstico por imagen , Hiperbilirrubinemia/metabolismo , Hipoxia/metabolismo , Oxihemoglobinas/metabolismo , Anemia de Células Falciformes/complicaciones , Anemia de Células Falciformes/diagnóstico por imagen , Enfermedades Arteriales Cerebrales/epidemiología , Enfermedades Arteriales Cerebrales/etiología , Enfermedades Arteriales Cerebrales/metabolismo , Niño , Estudios de Cohortes , Femenino , Humanos , Hipoxia/epidemiología , Hipoxia/etiología , Ataque Isquémico Transitorio/epidemiología , Modelos Logísticos , Londres/epidemiología , Angiografía por Resonancia Magnética , Imagen por Resonancia Magnética , Masculino , Análisis Multivariante , Oximetría , Reticulocitosis , Índice de Severidad de la Enfermedad , Accidente Cerebrovascular/epidemiología , Ultrasonografía Doppler Transcraneal
16.
Int J Dev Neurosci ; 58: 59-64, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28119021

RESUMEN

BACKGROUND AND OBJECTIVES: Developmental coordination disorder (DCD) is a prevalent childhood movement disorder, impacting the ability to perform movement skills at an age appropriate level. Although differences in grey matter (GM) volumes have been found in related developmental disorders, no such evidence has been linked with DCD to date. This cross-sectional study assessed structural brain differences in children with and without DCD. METHODS: High-resolution structural images were acquired from 44 children aged 7.8-12 years, including 22 children with DCD (≤16th percentile on MABC-2; no ADHD/ASD), and 22 typically developing controls (≥20th percentile on MABC-2). Structural voxel-based morphology analysis was performed to determine group differences in focal GM volumes. RESULTS: Children with DCD were found to have significant, large, right lateralised reductions in grey matter volume in the medial and middle frontal, and superior frontal gyri compared to controls. The addition of motor proficiency as a covariate explained the between-group GM volume differences, suggesting that GM volumes in motor regions are reflective of the level of motor proficiency. A positive correlation between motor proficiency and relative GM volume was also identified in the left posterior cingulate and precuneus. CONCLUSIONS: GM volume reductions in premotor frontal regions may underlie the motor difficulties characteristic of DCD. It is possible that intervention approaches targeting motor planning, attention, and executive functioning processes associated with the regions of reduced GM volume may result in functional improvements in children with DCD.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/etiología , Encéfalo/patología , Sustancia Gris/diagnóstico por imagen , Trastornos de la Destreza Motora/complicaciones , Trastornos de la Destreza Motora/patología , Trastornos del Movimiento/etiología , Trastorno por Déficit de Atención con Hiperactividad/diagnóstico por imagen , Niño , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Trastornos de la Destreza Motora/diagnóstico por imagen , Trastornos del Movimiento/diagnóstico por imagen
17.
Hum Mol Genet ; 25(19): 4302-4314, 2016 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-27506977

RESUMEN

RNA polymerase III is essential for the transcription of non-coding RNAs, including tRNAs. Mutations in the genes encoding its largest subunits are known to cause hypomyelinating leukodystrophies (HLD7) with pathogenetic mechanisms hypothesised to involve impaired availability of tRNAs. We have identified a founder mutation in the POLR3A gene that leads to aberrant splicing, a premature termination codon and partial deficiency of the canonical full-length transcript. Our clinical and imaging data showed no evidence of the previously reported white matter or cerebellar involvement; instead the affected brain structures included the striatum and red nuclei with the ensuing clinical manifestations. Our transcriptome-wide investigations revealed an overall decrease in the levels of Pol III-transcribed tRNAs and an imbalance in the levels of regulatory ncRNAs such as small nuclear and nucleolar RNAs (snRNAs and snoRNAs). In addition, the Pol III mutation was found to exert complex downstream effects on the Pol II transcriptome, affecting the general regulation of RNA metabolism.


Asunto(s)
Cuerpo Estriado/patología , Degeneración Nerviosa/congénito , ARN Polimerasa III/genética , Transcripción Genética , Transcriptoma/genética , Adulto , Cerebelo/metabolismo , Cerebelo/patología , Niño , Cuerpo Estriado/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Mutación , Neostriado/metabolismo , Neostriado/patología , Degeneración Nerviosa/genética , Degeneración Nerviosa/patología , Fenotipo , Empalme del ARN/genética , ARN de Transferencia/genética
18.
J Neurosurg Spine ; 25(4): 517-522, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27203812

RESUMEN

OBJECTIVE An objective biomarker for pain is yet to be established. Functional MRI (fMRI) is a promising neuroimaging technique that may reveal an objective radiological biomarker. The purpose of this study was to evaluate fMRI technology in the setting of lumbosacral radiculopathy and discuss its application in revealing a biomarker for pain in the future. METHODS A prospective, within-participant control study was conducted. Twenty participants with painful lumbosacral radiculopathy from intervertebral disc pathology were recruited. Functional imaging of the brain was performed during a randomly generated series of nonprovocative and provocative straight leg raise maneuvers. RESULTS With a statistical threshold set at p < 0.000001, 3 areas showed significant blood oxygen level-dependent (BOLD) signal change: right superior frontal gyrus (x = 2, y = 13, z = 48, k = 29, Brodmann area 6 [BA6]), left supramarginal cortex (x = -37, y = -44, z = 33, k = 1084, BA40), and left parietal cortex (x = -19, y = -41, z = 63, k = 354, BA5). With a statistical threshold set at p < 0.0002, 2 structures showed significant BOLD signal change: right putamen (x = 29, y = -11, z = 6, k = 72) and bilateral thalami (right: x = 23, y = -11, z = 21, k = 29; x = 8, y = -11, z = 9, k = 274; and left: x = -28, y = -32, z = 6, k = 21). CONCLUSIONS The results in this study compare with those in previous studies and suggest that fMRI technology can provide an objective assessment of the pain experience.


Asunto(s)
Encéfalo/diagnóstico por imagen , Encéfalo/fisiopatología , Dolor de la Región Lumbar/diagnóstico por imagen , Dolor de la Región Lumbar/fisiopatología , Imagen por Resonancia Magnética , Dimensión del Dolor/métodos , Adulto , Anciano , Circulación Cerebrovascular/fisiología , Femenino , Humanos , Degeneración del Disco Intervertebral/complicaciones , Degeneración del Disco Intervertebral/diagnóstico por imagen , Degeneración del Disco Intervertebral/fisiopatología , Degeneración del Disco Intervertebral/cirugía , Desplazamiento del Disco Intervertebral/complicaciones , Desplazamiento del Disco Intervertebral/diagnóstico por imagen , Desplazamiento del Disco Intervertebral/fisiopatología , Desplazamiento del Disco Intervertebral/cirugía , Pierna/fisiopatología , Dolor de la Región Lumbar/etiología , Dolor de la Región Lumbar/cirugía , Masculino , Persona de Mediana Edad , Movimiento/fisiología , Oxígeno/sangre , Estudios Prospectivos , Resultado del Tratamiento , Adulto Joven
20.
J Neurosurg ; 124(1): 96-105, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26295914

RESUMEN

The subthalamic nucleus (STN) is one of the most important stereotactic targets in neurosurgery, and its accurate imaging is crucial. With improving MRI sequences there is impetus for direct targeting of the STN. High-quality, distortion-free images are paramount. Image reconstruction techniques appear to show the greatest promise in balancing the issue of geometrical distortion and STN edge detection. Existing spin echo- and susceptibility-based MRI sequences are compared with new image reconstruction methods. Quantitative susceptibility mapping is the most promising technique for stereotactic imaging of the STN.


Asunto(s)
Estimulación Encefálica Profunda/métodos , Imagen por Resonancia Magnética/métodos , Núcleo Subtalámico/anatomía & histología , Núcleo Subtalámico/cirugía , Electrodos Implantados , Humanos , Procesamiento de Imagen Asistido por Computador , Procedimientos Neuroquirúrgicos/métodos , Técnicas Estereotáxicas
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