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1.
Invest Ophthalmol Vis Sci ; 65(1): 47, 2024 Jan 02.
Article in English | MEDLINE | ID: mdl-38294804

ABSTRACT

Purpose: To compare optical coherence tomography angiography (OCTA) retina metrics between cognitively healthy subjects with pathological versus normal cerebrospinal fluid (CSF) Aß42/tau ratios. Methods: Swept-source OCTA scans were collected using the Zeiss PLEX Elite 9000 and analyzed on 23 cognitively healthy (CH) subjects who had previously undergone CSF analysis. Thirteen subjects had a pathological Aß42/tau (PAT) ratio of <2.7132, indicative of presymptomatic Alzheimer's disease (AD), and 10 had a normal Aß42/tau (NAT) ratio of ≥2.7132. OCTA en face images of the superficial vascular complex (SVC) and deep vascular complex were binarized and skeletonized to quantify the perfusion density (PD), vessel length density (VLD), and fractal dimension (FrD). The foveal avascular zone (FAZ) area was calculated using the SVC slab. Choriocapillaris flow deficits (CCFDs) were computed from the en face OCTA slab of the CC. The above parameters were compared between CH-PATs and CH-NATs. Results: Compared to CH-NATs, CH-PATs showed significantly decreased PD, VLD, and FrD in the SVC, with a significantly increased FAZ area and CCFDs. Conclusions: Swept-source OCTA analysis of the SVC and CC suggests a significant vascular loss at the CH stage of pre-AD that might be an indicator of a neurodegenerative process initiated by the impaired clearance of Aß42 in the blood vessel wall and by phosphorylated tau accumulation in the perivascular spaces, a process that most likely mirrors that in the brain. If confirmed in larger longitudinal studies, OCTA retinal and inner choroidal metrics may be important biomarkers for assessing presymptomatic AD.


Subject(s)
Alzheimer Disease , Macula Lutea , Humans , Alzheimer Disease/diagnostic imaging , Angiography , Choroid , Retina/diagnostic imaging , Tomography, Optical Coherence , Cerebrospinal Fluid , Amyloidogenic Proteins , Neurodegenerative Diseases
2.
Front Genet ; 14: 1251216, 2023.
Article in English | MEDLINE | ID: mdl-37745862

ABSTRACT

Dominant optic atrophy (DOA) is an inherited disease that leads to the loss of retinal ganglion cells (RGCs), the projection neurons that relay visual information from the retina to the brain through the optic nerve. The majority of DOA cases can be attributed to mutations in optic atrophy 1 (OPA1), a nuclear gene encoding a mitochondrial-targeted protein that plays important roles in maintaining mitochondrial structure, dynamics, and bioenergetics. Although OPA1 is ubiquitously expressed in all human tissues, RGCs appear to be the primary cell type affected by OPA1 mutations. DOA has not been extensively studied in human RGCs due to the general unavailability of retinal tissues. However, recent advances in stem cell biology have made it possible to produce human RGCs from pluripotent stem cells (PSCs). To aid in establishing DOA disease models based on human PSC-derived RGCs, we have generated iPSC lines from two DOA patients who carry distinct OPA1 mutations and present very different disease symptoms. Studies using these OPA1 mutant RGCs can be correlated with clinical features in the patients to provide insights into DOA disease mechanisms.

3.
J Neuroophthalmol ; 43(4): 514-519, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-37247230

ABSTRACT

BACKGROUND: Peripapillary vitreous traction (PVT) occurring without any underlying eye disease has been contemplated as a distinct entity from nonarteritic ischemic optic neuropathy (NAION) for many years and is sometimes difficult to differentiate from classical NAION. We report 6 new cases to analyze the clinical features of PVT syndrome that would expand the clinical spectrum of anterior optic neuropathies. METHODS: Prospective case series. RESULTS: PVT syndrome seems to affect optic discs with a small area with a small cup-to-disc (C/D) ratio. The C/D ratio does not significantly increase in the chronic stage, as in NAION. Vitreous traction without detachment can either lead to mild retinal nerve fiber layer (RNFL) injury with attendant ganglion cell layer/inner plexiform layer (GCL/IPL) thinning in 29% or no injury at all in 71%. Eighty-six percent had good visual acuity (VA) and had no relative afferent pupillary defect (RAPD), whereas 14% had a transient RAPD; 71% had no color defect. Vitreous detachment after a period of severe and persistent traction can lead to more damage to the optic nerve head and RNFL that may look like NAION. Our hypothesized mechanically induced injury to the superficial optic nerve head may not lead to much visual impairment. In our study, no further therapeutic interventions were required. CONCLUSIONS: Based on our analysis of previously published cases and our own prospective case series of 6 patients, the PVT syndrome falls within the spectrum of anterior optic neuropathies, often affecting small optic discs with a small C/D ratio. Vitreous traction can lead to a partial or complete anterior optic neuropathy. The PVT syndrome may be a "more" anterior optic neuropathy distinct from classical NAION.


Subject(s)
Optic Neuropathy, Ischemic , Retinal Diseases , Humans , Retinal Ganglion Cells , Traction , Tomography, Optical Coherence , Visual Acuity , Nerve Fibers
4.
Mitochondrion ; 62: 181-186, 2022 01.
Article in English | MEDLINE | ID: mdl-34915201

ABSTRACT

In this retrospective, interventional, longitudinal small case series, we looked at the visual effects of pharmacologic intervention with 4-aminopyridine (4-AP) in chronic Leber's Hereditary Optic Neuropathy (LHON) patients who are non-responders to idebenone. We illustrate, as examples, the visual progression of three LHON patients with 4-AP as add-on therapy to idebenone. Each patient had a different primary LHON mutation and was treated with idebenone within one year of onset. No response to idebenone at 300 mg orally three times a day ranged from less than one year to 2.5 years, and the addition of 4-AP at 10 mg orally two times a day ranged from 24 to 29 months. Outcome measures included best-corrected distance visual acuity, color vision, automated perimetry, the average retinal nerve fiber layer (RNFL) thickness, and the full-field photopic negative response (PhNR) amplitude. The 19-year-old man with the LHON mutation 11778A > G had no response to the addition of 4-AP to idebenone. The 27-year-old man with the LHON mutation 3460A > G experienced a significant response to 4-AP. Finally, the 40-year-old man with the LHON mutation 14484 T > C had a milder response. Although this case series was too small to demonstrate the efficacy of idebenone with add-on 4AP, it allowed us to consider a new hypothesis that neuronal activity generated from 4-AP can add more potential for visual recovery in LHON patients.


Subject(s)
4-Aminopyridine/therapeutic use , Nerve Net/drug effects , Neurons/drug effects , Optic Atrophy, Hereditary, Leber/drug therapy , Ubiquinone/analogs & derivatives , 4-Aminopyridine/administration & dosage , Adult , DNA, Mitochondrial/genetics , Drug Therapy, Combination , Humans , Male , Retrospective Studies , Ubiquinone/administration & dosage , Ubiquinone/therapeutic use , Young Adult
5.
Mitochondrion ; 60: 142-149, 2021 09.
Article in English | MEDLINE | ID: mdl-34390870

ABSTRACT

INTRODUCTION: Isolated complex I deficiency causes several clinical syndromes, including Leigh syndrome (LS), Leber hereditary optic neuropathy (LHON) and mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes (MELAS). Here we reported two new patients carrying the rare m.3890G>A/MT-ND1 (p.Arg195Gln) mitochondrial DNA (mtDNA) pathogenic variant, revisited another two previously reported cases, and reviewed the remaining published cases, to refine the clinical and neuroimaging features. We also quantitatively assessed the mtDNA heteroplasmy in all available tissues. CASES PRESENTATION: The first patient was a 25-year-old male presenting with axonal polyneuropathy, optic atrophy consistent with LHON, gaze palsy and parkinsonism. MRI correlates included transient centromedullary T2 hyperintensity in the conus medullaris, transient signal intensity and increased lactate in the midbrain periaqueductal gray matter, and late atrophy of the optic nerves and chiasm, dorsal midbrain and conus medullaris. The second patient was a 65-year-old woman with a classical LHON phenotype and a normal MRI. DISCUSSION: Including the previously published cases, the clinical spectrum ranged from LHON to Leigh-like syndrome with peculiar CNS lesions and encephalopatic clinical symptoms. The most severe and complex cases were associated with very high heteroplasmy, or nearly homoplasmic m.3890G>A/MT-ND1 pathogenic variant in skeletal muscle, displaying neurological symptoms/signs consistent with Leigh-like lesions on brain MRI. Lower heteroplasmic mutational loads were instead associated with isolated LHON-like optic neuropathy of variable severity. CONCLUSION: The m.3890G>A/MT-ND1 mtDNA pathogenic variant increasingly impairs complex I function dependent on heteroplasmic loads, leading to a spectrum of LHON and Leigh-like encephalopathy with distinguishing MRI features.


Subject(s)
DNA, Mitochondrial/genetics , Optic Atrophy, Hereditary, Leber/genetics , Optic Atrophy, Hereditary, Leber/pathology , Adult , Aged , Female , Heteroplasmy , Humans , Male , Mutation
6.
Trials ; 22(1): 508, 2021 Jul 31.
Article in English | MEDLINE | ID: mdl-34332638

ABSTRACT

BACKGROUND: Although Alzheimer's disease affects around 800,000 people in the UK and costs almost £23 billion per year, currently licenced treatments only offer modest benefit at best. Seizures, which are more common in patients with Alzheimer's disease than age matched controls, may contribute to the loss of nerve cells and abnormal brain discharges can disrupt cognition. This aberrant electrical activity may therefore present potentially important drug targets. The anti-seizure medication levetiracetam can reduce abnormal cortical discharges and reverse memory deficits in a mouse model of Alzheimer's disease. Levetiracetam has also been shown to improve memory difficulties in patients with mild cognitive impairment, a precursor to Alzheimer's disease. Clinical use of levetiracetam is well-established in treatment of epilepsy and extensive safety data are available. Levetiracetam thus has the potential to provide safe and efficacious treatment to help with memory difficulties in Alzheimer's disease. METHODS: The proposed project is a proof of concept study to test whether levetiracetam can help cognitive function in people with dementia. We plan to recruit thirty patients with mild to moderate Alzheimer's disease with no history of previous seizures or other significant co-morbidity. Participants will be allocated to a double-blind placebo-controlled crossover trial that tests levetiracetam against placebo. Standardised scales to assess cognition and a computer-based touchscreen test that we have developed to better detect subtle improvements in hippocampal function will be used to measure changes in memory. All participants will have an electroencephalogram (EEG) at baseline. The primary outcome measure is a change in the computer-based touchscreen cognitive task while secondary outcomes include the effect of levetiracetam on mood, quality of life and modelling of the EEG, including time series measures and feature-based analysis to see whether the effect of levetiracetam can be predicted. The effect of levetiracetam and placebo will be compared within a given patient using the paired t-test and the analysis of covariance adjusting for baseline values. DISCUSSION: This is the first study to evaluate if an anti-seizure medication can offer meaningful benefit to patients with Alzheimer's disease. If this study demonstrates at least stabilisation of memory function and/or good tolerability, the next step will be to rapidly progress to a larger study to establish whether levetiracetam may be a useful and cost-effective treatment for patients with Alzheimer's disease. TRIAL REGISTRATION: ClinicalTrials.gov NCT03489044 . Registered on April 5, 2018.


Subject(s)
Alzheimer Disease , Alzheimer Disease/diagnosis , Alzheimer Disease/drug therapy , Animals , Cross-Over Studies , Double-Blind Method , Humans , Levetiracetam/adverse effects , Mice , Proof of Concept Study , Quality of Life
8.
EBioMedicine ; 64: 103220, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33529999

ABSTRACT

BACKGROUND: Overexpression of epidermal growth factor receptor (EGFR), and downstream pathway activation appears to be a common oncogenic driver in the majority of head and neck squamous cell cancers (HNSCCs); yet targeting EGFR for the treatment of HNSCC has met with limited success. Apart from the anti-EGFR antibody cetuximab, no small molecule EGFR/tyrosine kinase inhibitors (TKIs) have progressed to routine clinical use. The aim of this study was to determine factors contributing to the lack of response to TKIs and identify alternative therapeutic vulnerabilities. METHODS: Genomic and transcriptomic sequencing, high-throughput compound screens, overexpression and siRNA knockdown, western blot, in vivo xenograft studies. FINDINGS: We derived three pairs of isogenic gefitinib (TKI)-sensitive and resistant patient-derived HNSCC cell lines. Genomic sequencing of gefitinib-resistant cell lines identified a lack of activating and resistance-associated EGFR mutations. Instead, transcriptomic sequencing showed upregulated EMT gene signature in the gefitinib-resistant cells with a corresponding increase in their migratory phenotype. Additionally, the resistant cell displayed reduced growth rate. Surprisingly, while gefitinib-resistant cells were independent of EGFR for survival, they nonetheless displayed activation of downstream ERK and AKT signalling. High-throughput screening (HTS) of druggable, small molecule libraries revealed that the gefitinib-resistant cells were particularly sensitive to inhibitors of genes involved in cell cycle and mitosis, such as Aurora kinase inhibitors (AKIs), cyclin-dependent kinase (CDK) inhibitors, and microtubule inhibitors. Notably our results showed that in the EGFR inhibited state, Aurora kinases are essential for cell survival. INTERPRETATION: Our study demonstrates that in the absence of activating EGFR mutations, HNSCCs may gain resistance to gefitinib through decreased cell proliferation, which makes them exceptionally vulnerable to cell-cycle inhibitors. FUNDING: Agency for Science, Technology, and Research (A*STAR), National Medical Research Council (NMRC), and the National Institutes of Health (NIH)/National Cancer Institute (NCI).


Subject(s)
Aurora Kinases/antagonists & inhibitors , Aurora Kinases/metabolism , Biomarkers, Tumor , Drug Resistance, Neoplasm/genetics , Drug Screening Assays, Antitumor , Gefitinib/pharmacology , Mutation , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Cell Survival/genetics , Epithelial-Mesenchymal Transition/drug effects , ErbB Receptors/genetics , Fluorescent Antibody Technique , Humans , Models, Biological , Small Molecule Libraries , Squamous Cell Carcinoma of Head and Neck
9.
Eye Brain ; 13: 21-28, 2021.
Article in English | MEDLINE | ID: mdl-33500674

ABSTRACT

Glaucoma, a group of diseases characterized by progressive optic nerve degeneration that results in irreversible blindness, can be considered a neurodegenerative disorder of both the eye and the brain. Increasing evidence from human and animal studies have shown that glaucoma shares some common neurodegenerative pathways with Alzheimer's disease (AD) and other tauopathies, such as chronic traumatic encephalopathy (CTE) and frontotemporal dementia. This hypothesis is based on the focal adhesion pathway hypothesis and the spreading hypothesis of tau. Not only has the Apolipoprotein E (APOE) gene been shown to be associated with AD, but also with primary open angle glaucoma (POAG). This review will highlight the relevant literature in the past 20 years from PubMed that show the pathogenic overlap between POAG and AD. Neurodegenerative pathways that contribute to transsynaptic neurodegeneration in AD and other tauopathies might also be similar to those in glaucomatous neurodegeneration.

10.
Prog Retin Eye Res ; 83: 100938, 2021 07.
Article in English | MEDLINE | ID: mdl-33460813

ABSTRACT

Retinal imaging technology is rapidly advancing and can provide ever-increasing amounts of information about the structure, function and molecular composition of retinal tissue in humans in vivo. Most importantly, this information can be obtained rapidly, non-invasively and in many cases using Food and Drug Administration-approved devices that are commercially available. Technologies such as optical coherence tomography have dramatically changed our understanding of retinal disease and in many cases have significantly improved their clinical management. Since the retina is an extension of the brain and shares a common embryological origin with the central nervous system, there has also been intense interest in leveraging the expanding armamentarium of retinal imaging technology to understand, diagnose and monitor neurological diseases. This is particularly appealing because of the high spatial resolution, relatively low-cost and wide availability of retinal imaging modalities such as fundus photography or OCT compared to brain imaging modalities such as magnetic resonance imaging or positron emission tomography. The purpose of this article is to review and synthesize current research about retinal imaging in neurodegenerative disease by providing examples from the literature and elaborating on limitations, challenges and future directions. We begin by providing a general background of the most relevant retinal imaging modalities to ensure that the reader has a foundation on which to understand the clinical studies that are subsequently discussed. We then review the application and results of retinal imaging methodologies to several prevalent neurodegenerative diseases where extensive work has been done including sporadic late onset Alzheimer's Disease, Parkinson's Disease and Huntington's Disease. We also discuss Autosomal Dominant Alzheimer's Disease and cerebrovascular small vessel disease, where the application of retinal imaging holds promise but data is currently scarce. Although cerebrovascular disease is not generally considered a neurodegenerative process, it is both a confounder and contributor to neurodegenerative disease processes that requires more attention. Finally, we discuss ongoing efforts to overcome the limitations in the field and unmet clinical and scientific needs.


Subject(s)
Neurodegenerative Diseases , Retinal Diseases , Diagnostic Techniques, Ophthalmological , Humans , Neurodegenerative Diseases/diagnostic imaging , Retina/diagnostic imaging , Retinal Diseases/diagnostic imaging , Tomography, Optical Coherence
12.
Nat Commun ; 11(1): 2086, 2020 04 29.
Article in English | MEDLINE | ID: mdl-32350249

ABSTRACT

Gain of function (GOF) DNA binding domain (DBD) mutations of TP53 upregulate chromatin regulatory genes that promote genome-wide histone methylation and acetylation. Here, we therapeutically exploit the oncogenic GOF mechanisms of p53 codon 158 (Arg158) mutation, a DBD mutant found to be prevalent in lung carcinomas. Using high throughput compound screening and combination analyses, we uncover that acetylating mutp53R158G could render cancers susceptible to cisplatin-induced DNA stress. Acetylation of mutp53R158G alters DNA binding motifs and upregulates TRAIP, a RING domain-containing E3 ubiquitin ligase which dephosphorylates IĸB and impedes nuclear translocation of RelA (p65), thus repressing oncogenic nuclear factor kappa-B (NF-ĸB) signaling and inducing apoptosis. Given that this mechanism of cytotoxic vulnerability appears inapt in p53 wild-type (WT) or other hotspot GOF mutp53 cells, our work provides a therapeutic opportunity specific to Arg158-mutp53 tumors utilizing a regimen consisting of DNA-damaging agents and mutp53 acetylators, which is currently being pursued clinically.


Subject(s)
Codon/genetics , Mutation/genetics , Neoplasms/genetics , Tumor Suppressor Protein p53/genetics , Acetylation/drug effects , Animals , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Apoptosis/drug effects , Apoptosis/genetics , Caspase 3/metabolism , Cell Line, Tumor , Cell Proliferation/drug effects , Cisplatin/pharmacology , Epigenesis, Genetic/drug effects , Gain of Function Mutation/genetics , Gene Expression Regulation, Neoplastic/drug effects , Humans , Hydroxamic Acids/pharmacology , Mice, SCID , Models, Biological , Mutant Proteins/metabolism , NF-kappa B/metabolism , Neoplasms/drug therapy , Nucleotide Motifs/genetics , Poly(ADP-ribose) Polymerases/metabolism , Protein Binding/drug effects , Protein Isoforms/genetics , Sulfonamides/pharmacology , Topotecan/pharmacology , Ubiquitin-Protein Ligases/genetics , Ubiquitin-Protein Ligases/metabolism , Xenograft Model Antitumor Assays
13.
Epilepsia ; 61(4): 647-656, 2020 04.
Article in English | MEDLINE | ID: mdl-32329527

ABSTRACT

OBJECTIVE: To evaluate the effectiveness and tolerability of lacosamide added to one or two antiepileptic drugs (AEDs) in the treatment of patients with brain tumor-related epilepsy (BTRE), and to evaluate patients' global impression of change and quality of life (QoL). METHODS: This was a prospective, multicenter, single-arm, noninterventional study with a 6-month observation period (EP0045; NCT02276053). Eligible patients (≥16 years old) had active BTRE secondary to low-grade glioma (World Health Organization grade 1 and 2) and were receiving treatment with one or two AEDs at baseline. Lacosamide was initiated by the treating physician in the course of routine clinical practice. Primary outcomes were 50% responders (≥50% reduction in focal seizure frequency from baseline) and Patient's Global Impression of Change (PGIC) at month 6. Secondary outcomes included seizure-free status and Clinical Global Impression of Change (CGIC) at month 6, change in QoL (5-Level EuroQol-5 Dimension Quality of Life Assessment) and symptom outcomes (MD Anderson Symptom Inventory-Brain Tumor) from baseline to month 6, and Kaplan-Meier estimated 6-month retention on lacosamide. Safety variables included adverse drug reactions (ADRs). RESULTS: Patients were recruited from 24 sites in Europe. Ninety-three patients received lacosamide (mean [standard deviation] age = 44.5 [14.7] years; 50 [53.8%] male; median baseline focal seizure frequency = five seizures/28 days [range = 1-280]), of whom 79 (84.9%) completed the study. At 6 months, 66 of 86 (76.7%) patients were 50% responders and 30 of 86 (34.9%) were seizure-free. Improvements on PGIC were reported by 49 of 76 (64.5%) patients. Based on CGIC, 52 of 81 (64.2%) patients improved. QoL and symptoms outcome measures remained stable. Kaplan-Meier estimated 6-month retention rate was 86.0% (N = 93). Fifteen (16.1%) patients reported ADRs; four (4.3%) had ADRs leading to discontinuation (N = 93). SIGNIFICANCE: Results of this prospective, noninterventional study suggest that add-on lacosamide is effective and generally well tolerated in patients with BTRE.


Subject(s)
Anticonvulsants/therapeutic use , Brain Neoplasms/complications , Epilepsy/drug therapy , Epilepsy/etiology , Lacosamide/therapeutic use , Adult , Chemotherapy, Adjuvant/methods , Drug Therapy, Combination/methods , Female , Humans , Male , Middle Aged , Prospective Studies , Quality of Life , Treatment Outcome
14.
BMC Neurol ; 20(1): 7, 2020 Jan 08.
Article in English | MEDLINE | ID: mdl-31914953

ABSTRACT

BACKGROUND: In elderly patients (≥65 years of age) with epilepsy who take medications for comorbid conditions, some antiepileptic drugs (AEDs) may alter the metabolism of other treatments and increase the risk of adverse consequences and healthcare utilisation. This analysis compares healthcare costs associated with enzyme-inducing AEDs (EIAEDs) and non-enzyme active AEDs (nEAAEDs) use in elderly patients with epilepsy. METHODS: This retrospective matched cohort study used the Clinical Practice Research Datalink (CPRD) of UK primary care medical records, linked to the Hospital Episode Statistics (HES) database. Selected patients with epilepsy were ≥ 65 years and prescribed an EIAED or nEAAED between 2001 and 2010 (index) after ≥1 year without AEDs (baseline) and followed until the first occurrence of the following: end of HES data coverage, end of GP registration, or death; practice's up-to-standard status or addition of an AED belonging to another cohort or discontinuation of the last AED of that cohort. Propensity score matching reduced confounding factor effects between cohorts. Key outcomes included time to cohort treatment failure, time to index AED treatment failure, and direct healthcare costs in 2014 Pound Sterling (£) values. RESULTS: Overall, 1425 elderly patients were included: 964 with EIAEDs and 461 with nEAAEDs. At baseline, the EIAED cohort was older (mean age, 76.2 vs. 75.1 years) and a higher proportion were male. Baseline direct healthcare costs were similar. After matching (n = 210 each), and over the entire follow-up period, median monthly direct healthcare costs were higher for patients taking EIAEDs than nEAAEDs (£403 vs. £317; p = 0.0150, Mann-Whitney U). Costs were higher for patients remaining in the EIAED cohort after 3 follow-up years. The median time to cohort treatment failure for the EIAED cohort was 1110 days vs. 1175 days for the nEAAED cohort. CONCLUSION: Newly treated elderly patients with epilepsy were more likely to be prescribed EIAEDs than nEAAEDs. In matched cohorts, elderly patients with epilepsy treated with EIAEDs had higher average total direct and epilepsy-related healthcare costs than nEAAED-treated patients; this difference was greater than previously reported in the overall adult population. Changing treatment practices could improve patient care and reduce costs.


Subject(s)
Anticonvulsants/economics , Anticonvulsants/therapeutic use , Epilepsy/drug therapy , Epilepsy/economics , Aged , Cohort Studies , Comorbidity , Drug Therapy, Combination/economics , Female , Health Care Costs , Humans , Male , Propensity Score , Retrospective Studies , United Kingdom
15.
Invest Ophthalmol Vis Sci ; 60(6): 2005-2011, 2019 05 01.
Article in English | MEDLINE | ID: mdl-31067321

ABSTRACT

Purpose: To analyze the clinical presentation and optical coherence tomography (OCT) findings in indirect traumatic optic neuropathy (ITON) in veterans with chronic mild traumatic brain injury (mTBI). Methods: This retrospective study is the first to describe the OCT pattern of subclinical to mild ITON in veterans with chronic mTBI. The thicknesses of the macular ganglion cell layer (mGCL), peripapillary retinal nerve fiber layer (pRNFL), and subfoveal choroidal layer were analyzed in young veterans who had mTBI of >6 months' duration and either blunt head injury or improvised explosive device (IED) concussions. Results: Three major OCT findings were demonstrated: (1) temporal pRNFL thinning was associated with subclinical TON in the eyes of chronic mTBI patients compared with controls; within mTBI subjects, nasal mGCL thinning at the 3-mm modified Early Treatment Diabetic Retinopathy Study circle diameter distance from the fovea correlated with the corresponding temporal retinal nerve fiber layer thinning; (2) inner (1 mm) superior thinning was greater than that of the temporal mGCL in blunt head injury and could potentially distinguish it from IED concussive head trauma; and (3) subfoveal choroidal thinning was significantly worse in eyes of mTBI patients compared with those of controls. Conclusions: These OCT findings may contribute to the understanding of the spectrum of visual injuries resulting from head trauma.


Subject(s)
Brain Concussion/complications , Optic Disk/pathology , Optic Nerve Injuries/etiology , Retinal Ganglion Cells/pathology , Visual Acuity , Adult , Brain Concussion/diagnosis , Chronic Disease , Female , Follow-Up Studies , Humans , Male , Nerve Fibers/pathology , Optic Nerve Injuries/diagnosis , Prognosis , Retrospective Studies , Tomography, Optical Coherence
16.
Article in English | MEDLINE | ID: mdl-30366425

ABSTRACT

With the growing interest among researchers, practitioners, and urban decision makers in the influence of the built environment on peoples' health, there is increasing emphasis on using scientific knowledge to inform urban design, including methods of neuroscience. As window views are the most immediate medium of visual connection with one's neighbourhood, we surmised that the quality of this view would have an impact on the mental health and well-being of urban dwellers. Accordingly, we investigated how window views taken from different floors of a high-rise block with varying extents of green cover affected 29 healthy residents in an exploratory electroencephalography (EEG) experiment. The results showed that the amount of green cover within the view captured at different floor levels can cause an important interaction effect on the frontal alpha and temporal beta brain oscillations while participants view photographs. These results suggest that the brainwave patterns commonly associated with positive emotional states, motivation, and visual attention mechanisms may be increased by the extent of green cover within the view. This phenomenon seems more pronounced on the higher than lower floors. The observed findings at this stage cannot confirm major effects between floor level, green cover, and brainwaves, however, they emphasize the importance of considering the quality of window views in the planning and design of urban high-rise neighbourhoods. Having a green window view can potentially contribute to the mental health and well-being of urban dwellers.


Subject(s)
Brain/physiology , Residence Characteristics , Urban Population , Visual Perception , Adult , Aged , Alpha Rhythm , Attention , Beta Rhythm , Electroencephalography , Emotions , Female , Humans , Male , Mental Health , Middle Aged , Motivation , Singapore , Young Adult
17.
BMC Neurol ; 17(1): 59, 2017 Mar 23.
Article in English | MEDLINE | ID: mdl-28335764

ABSTRACT

BACKGROUND: Some antiepileptic drugs (AEDs) induce expression of hepatic enzymes. This can contribute to comorbidities via interference with metabolic pathways and concomitant drug metabolization, thereby increasing the likelihood of health care interventions. Using medical records, we compared the direct health care cost in patients initiating epilepsy therapy with enzyme-inducing AEDs (EIAEDs) vs non-enzyme-active AEDs (nEAAEDs) over up to 12 years. METHODS: Patients with untreated epilepsy were indexed in the UK Clinical Practice Research Datalink and Hospital Episode Statistics database when prescribed a new EIAED or nEAAED between January 2001 and December 2010. Propensity score matching reduced confounding factors between cohorts. Patients were followed until cohort treatment failure or data cut-off. The primary outcome was the median standardized monthly direct health care cost during follow-up in 2014 £GBP, calculated using published reference costs and compared using a Mann-Whitney U test. RESULTS: The unmatched EIAED cohort (n = 2752) was older (54 vs 46 years), more likely to be male, had more comorbidities, and higher health care resource use/cost during the 1-year pre-index period (median £3014 vs £2516) than the nEAAED cohort (n = 2,137). The most common index EIAED and nEAAED were carbamazepine (63.3%) and lamotrigine (58.0%), respectively. After matching, cohorts had similar features (n = 951 each). Over up to 12 years of follow-up, the median standardized monthly direct health care cost was £229 for the EIAED and £188 for the nEAAED cohorts (p = 0.0091). The median cost was higher for the EIAED cohort in every year of follow-up. In the two cohorts, 25.1% and 20.1% of total mean cost during follow-up was epilepsy-related, with approximately 4.6% and 3.0% for AED acquisition, respectively. The median time to cohort treatment failure was shorter in the matched EIAED cohort (468 vs 1194 days). CONCLUSIONS: Patients in the UK who initiated epilepsy therapy with an EIAED appeared to be at higher risk of complications associated with enzyme induction. In long-term matched cohort analyses, the median total direct health care cost associated with EIAED therapy was higher than with nEAAEDs. Changing current treatment practices could potentially improve patient outcomes and reduce costs.


Subject(s)
Anticonvulsants , Cytochrome P-450 CYP3A Inducers , Drug-Related Side Effects and Adverse Reactions/economics , Epilepsy/drug therapy , Epilepsy/economics , Health Care Costs/statistics & numerical data , Outcome Assessment, Health Care/statistics & numerical data , Adolescent , Adult , Aged , Aged, 80 and over , Anticonvulsants/adverse effects , Anticonvulsants/economics , Anticonvulsants/therapeutic use , Comorbidity , Cytochrome P-450 CYP3A Inducers/adverse effects , Cytochrome P-450 CYP3A Inducers/economics , Cytochrome P-450 CYP3A Inducers/therapeutic use , Female , Humans , Male , Middle Aged , Propensity Score , Retrospective Studies , Treatment Failure , United Kingdom , Young Adult
18.
J Neurol ; 264(8): 1622-1633, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28144922

ABSTRACT

Since obesity has become an epidemic in industrialized nations, idiopathic intracranial hypertension (IIH) is now a more common neuro-ophthalmic disorder that causes visual loss and headaches. This review highlights the new diagnostic criteria for IIH and the new insights into the pathophysiologic mechanisms of IIH. Key diagnostic and monitoring techniques for papilledema include not only neuroimaging and the measurement of cerebrospinal fluid (CSF) pressure, but also perimetry, optical coherence tomography, and ocular sonography. The main findings of the Idiopathic Intracranial Hypertension Treatment Trial (IIHTT) support acetazolamide as the mainstay for medical therapy. CSF diversion procedures, endovascular venous sinus stenting, and optic nerve sheath fenestration are all surgical options when IIH is refractory to medical treatment or when it presents fulminantly. Future clinical trials comparing these procedures will help develop better paradigms in the surgical management of IIH.


Subject(s)
Intracranial Hypertension/diagnosis , Intracranial Hypertension/therapy , Animals , Humans , Intracranial Hypertension/etiology , Intracranial Hypertension/physiopathology
19.
J Neurosurg ; 126(2): 347-353, 2017 02.
Article in English | MEDLINE | ID: mdl-26967777

ABSTRACT

OBJECTIVE Cerebral venous pressure gradient (CVPG) from dural venous sinus stenosis is implicated in headache syndromes such as idiopathic intracranial hypertension (IIH). The incidence of CVPG in headache patients has not been reported. METHODS The authors reviewed all cerebral venograms with manometry performed for headache between January 2008 and May 2015. Patient demographics, headache etiology, intracranial pressure (ICP) measurements, and radiographic and manometric results were recorded. CVPG was defined as a difference ≥ 8 mm Hg by venographic manometry. RESULTS One hundred sixty-four venograms were performed in 155 patients. There were no procedural complications. Ninety-six procedures (58.5%) were for patients with IIH. The overall incidence of CVPG was 25.6% (42 of 164 procedures): 35.4% (34 of 96 procedures) in IIH patients and 11.8% (8 of 68 procedures) in non-IIH patients. Sixty procedures (36.6%) were performed in patients with preexisting shunts. Seventy-seven patients (49.7%) had procedures preceded by an ICP measurement within 4 weeks of venography, and in 66 (85.7%) of these patients, the ICP had been found to be elevated. CVPG was seen in 8.3% (n = 5) of the procedures in the 60 patients with a preexisting shunt and in 0% (n = 0) of the 11 procedures in the 77 patients with normal ICP (p < 0.001 for both). Noninvasive imaging (MR venography, CT venography) was assessed prior to venography in 112 (68.3%) of 164 cases, and dural venous sinus abnormalities were demonstrated in 73 (65.2%) of these cases; there was a trend toward CVPG (p = 0.07). Multivariate analysis demonstrated an increased likelihood of CVPG in patients with IIH (OR 4.97, 95% CI 1.71-14.47) and a decreased likelihood in patients with a preexisting shunt (OR 0.09, 95% CI 0.02-0.44). CONCLUSIONS CVPG is uncommon in IIH patients, rare in those with preexisting shunts, and absent in those with normal ICP.


Subject(s)
Cranial Sinuses/physiopathology , Intracranial Pressure/physiology , Pseudotumor Cerebri/complications , Pseudotumor Cerebri/physiopathology , Adult , Female , Humans , Incidence , Male , Manometry , Middle Aged , Phlebography , Retrospective Studies , Risk Factors , Sensitivity and Specificity
20.
Oncotarget ; 8(68): 112825-112840, 2017 Dec 22.
Article in English | MEDLINE | ID: mdl-29348869

ABSTRACT

Murine double minute 4 protein (MDMX) is crucial for the regulation of the tumor suppressor protein p53. Phosphorylation of the N-terminal domain of MDMX is thought to affect its binding with the transactivation domain of p53, thus playing a role in p53 regulation. In this study, the effects of MDMX phosphorylation on the binding of p53 were investigated using molecular dynamics simulations. It is shown that in addition to the previously proposed mechanism in which phosphorylated Y99 of MDMX inhibits p53 binding through steric clash with P27 of p53, the N-terminal lid of MDMX also appears to play an important role in regulating the phosphorylation-dependent interactions between MDMX and p53. In the proposed mechanism, phosphorylated Y99 aids in pulling the lid into the p53-binding pocket, thus inhibiting the binding between MDMX and p53. Rebinding of p53 appears to be facilitated by the subsequent phosphorylation of Y55, which draws the lid away from the binding pocket by electrostatic attraction of the lid's positively charged N-terminus. The ability to target these mechanisms for the proper regulation of p53 could have important implications for understanding cancer biology and for drug development.

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