Publications by authors named "Michaelides M"

The anterior hypothalamic area (AHA) is a key brain region for orchestrating defensive behaviors. Using in vivo calcium imaging in mice, we observed that AHA neuronal activity increases during foot shock delivery and foot-shock associated auditory cues. We found that following shock-induced increases in AHA activity, a decrease in activity coincides with the onset of grooming behavior.

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The U4 small nuclear RNA (snRNA) forms a duplex with the U6 snRNA and, together with U5 and ~30 proteins, is part of the U4/U6.U5 tri-snRNP complex, located at the core of the major spliceosome. Recently, recurrent variants in the U4 RNA, transcribed from the gene, and in at least two other genes were discovered to cause neurodevelopmental disorder.

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Purpose: To describe progression of best-corrected visual acuity (BCVA), full-field stimulus thresholds (FST), and electroretinography (ERG) over 4 years in the -related Retinal Degeneration study and to assess their suitability as clinical trial endpoints.

Design: Prospective natural history study.

Participants: Participants (n = 105) with biallelic disease-causing sequence variants in USH2A and BCVA letter scores of ≥54 were included.

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Ketamine is a racemic compound and medication comprised of ()-ketamine and ()-ketamine enantiomers and its metabolites. It has been used for decades as a dissociative anesthetic, analgesic, and recreational drug. More recently, ketamine, its enantiomers, and its metabolites have been used or are being investigated for the treatment of refractory depression, as well as for comorbid disorders such as anxiety, obsessive-compulsive, and opioid use disorders.

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Purpose: The purpose of this study was to analyze the retinal sensitivity under photopic, mesopic, and scotopic conditions in a cohort of patients affected with KCNV2-associated retinopathy.

Methods: Cross-sectional evaluation of molecularly confirmed individuals was conducted. Data were obtained prospectively.

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Purpose: Although it is well known that photoreceptor damage and color vision loss occur in patients with diabetic retinopathy (DR), the relationship between structural and functional changes in diabetes mellitus (DM) remains unclear. Using highly sensitive measures of photoreceptor structure and function, we aim to determine whether early loss of color sensitivity in DM is also accompanied by decreased cone density.

Methods: Monocular data from 26 patients with DM and 25 healthy controls were examined to assess cone photoreceptor metrics, using confocal adaptive optics scanning light ophthalmoscopy, and red/green (RG) and yellow/blue (YB) color vision thresholds, using the Colour Assessment and Diagnosis test.

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Purpose: Inherited retinal disorders (IRD) are a complex group of conditions. By developing the first patient-reported experience measurement (PREM) questionnaire tailored for individuals with IRD participating in natural history studies, we gathered information on individuals' views of their experience while they are involved in research.

Methods: Adults with IRD who (i) were enrolled in a natural history study taking place at Moorfields Eye Hospital (London, UK), (ii) had attended at least two study visits, (iii) the most recent one being less than two weeks before the questionnaire, and (iv) who were not involved in interventional research, were considered for participation.

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Background: Variants in CRX are associated with dominantly inherited retinopathy with considerable phenotypic variability. Many patients have central retinal degeneration; in some patients, we have observed an additional focus of degeneration in the nasal retina. This study explores this phenotypic association amongst patients with CRX-associated disease.

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Purpose: Retinitis pigmentosa (RP) is the most common diagnosis in the ophthalmic genetics clinic. Women with RP are often diagnosed during their reproductive years, posing significant challenges for family planning. The effects of pregnancy on RP progression is a frequently unanswered concern for these patients.

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Article Synopsis
  • * The study identifies a new autosomal dominant syndrome combining eye malformations, spine issues, and kidney problems in six different families, linked to mutations in a specific orphan nuclear receptor gene.
  • * Genetic experiments demonstrated that these mutations disrupt normal development in zebrafish, highlighting the gene's crucial role in both eye and vertebra formation.
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Colobomatous microphthalmia is a potentially blinding congenital ocular malformation that can present either in isolation or together with other syndromic features. Despite a strong genetic component to disease, many cases lack a molecular diagnosis. We describe a novel autosomal dominant oculo-vertebral-renal (OVR) syndrome in six independent families characterized by colobomatous microphthalmia, missing vertebrae and congenital kidney abnormalities.

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Stem cell-based therapy has gained importance over the past decades due to huge advances in science and technology behind the generation and directed differentiation of pluripotent cells from embryos and adult cells. Preclinical proof-of-concept studies have been followed by clinical trials showing efficacy and safety of transplantation of stem cell-based therapy, which are beginning to establish this as a modality of treatment. Disease candidates of interest are primarily conditions that may benefit from replacing dead or dying cells, including advanced inherited retinal dystrophies and age-related macular degeneration, and predominantly seek to transplant either RPE or photoreceptors, although neurotrophic approaches have also been trialed.

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  • Alcohol use disorder (AUD) often coexists with anxiety disorders, but it's unclear whether alcohol abuse leads to or results from anxiety issues.
  • Using inbred mice in a risk-avoidance test, researchers found that those showing higher anxiety-like behaviors experienced greater relief from alcohol, indicating a link between anxiety and alcohol consumption.
  • The study revealed that the balance of dopamine D1 and D2 receptors in the brain influences this relationship; a higher D1 to D2 ratio was associated with increased risk-avoidance and continued alcohol use, suggesting that anxiety traits might contribute to developing AUD.
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This study investigated the ventilatory thresholds (VT1 and VT2) along with the corresponding heart rates, velocities and % of V̇O max at which these thresholds are reached in professional female soccer players. It also examined positional differences in the aforementioned parameters. Thirty-three professional players from two teams (age range 18-31 years) were recruited.

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  • The study focuses on the challenges faced by health technology assessment (HTA) agencies in evaluating gene therapies for X-linked retinitis pigmentosa (XLRP), a rare eye disease, particularly regarding acceptability and the assessment of long-term value.
  • A literature review revealed that the societal value of XLRP gene therapy largely stems from productivity effects, carer spillovers, and patient uncertainty, yet evidence for these effects is limited.
  • The research highlights significant issues related to discounting in economic evaluations, suggesting a need for HTA agencies to adapt their frameworks to properly assess the value of innovative gene therapies.
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  • The study aims to evaluate how functional and structural assessments can serve as endpoints in clinical trials for retinal degeneration linked to USH2A mutations.
  • Participants with specific visual capabilities underwent various eye tests over four years, focusing on understanding changes in their vision.
  • Findings indicated that certain tests were more sensitive to detecting changes, influencing the design of future clinical trials related to this condition.
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  • The paper looks at how inherited retinal diseases (IRD) are diagnosed and treated in the Asia-Pacific region.
  • They surveyed 36 centers about their practices, including how they collect patient information and provide help for low vision.
  • The results showed there are important gaps, like many centers not having a database for patients, not enough genetic counselors, and a need for better support for low-vision rehabilitation.
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  • The study aimed to examine how the foveal cone structure changes over time in patients with CNGA3-associated achromatopsia (ACHM).
  • Thirteen eyes from ten patients were analyzed using advanced imaging techniques, finding no significant changes in outer nuclear layer thickness, foveal disruption, or cone density over an average follow-up of 2.6 years.
  • Results indicated stable foveal cone structure with a peak density of around 15,346 cones/mm² and changes so minor that no significant age-related trends could be established.
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Inhibition of the receptor tyrosine kinase MerTK by small molecules has the potential to augment the immune response to tumors. Potent, selective inhibitors with high levels of target engagement are needed to fully evaluate the potential use of MerTK inhibitors as cancer therapeutics. We report the discovery and optimization of a series of pyrazinamide-based type 1.

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Digital health is wielding a growing influence across all areas of healthcare, encompassing various facets such as telemedicine, artificial intelligence (AI), and electronic healthcare records. In Ophthalmology, digital health innovations can be broadly divided into four categories: (i) self-monitoring home devices and apps, (ii) virtual and augmented reality visual aids, (iii) AI software, and (iv) wearables. Wearable devices can work in the background, collecting large amounts of objective data while we do our day-to-day activities, which may be ecologically more valid and meaningful to patients than that acquired in traditional hospital settings.

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TAM receptor tyrosine kinases have emerged as promising therapeutic targets for cancer treatment due to their roles in both tumor intrinsic survival mechanisms and suppression of antitumor immunity within the tumor microenvironment. Inhibiting MerTK and Axl selectively is believed to hinder cancer cell survival, reverse the protumor myeloid phenotype, and suppress efferocytosis, thereby eliciting an antitumor immune response. In this study, we present the discovery of , a highly potent and selective dual MerTK/Axl inhibitor, achieved through a structure-based medicinal chemistry campaign.

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Purpose: To analyze the genetics, clinical characteristics, and natural history of PDE6A-associated retinitis pigmentosa.

Design: Retrospective, longitudinal, observational cohort study.

Participants: Patients with molecularly confirmed PDE6A-associated retinal dystrophy in a single tertiary referral center.

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Genome analysis of individuals affected by retinitis pigmentosa (RP) identified two rare nucleotide substitutions at the same genomic location on chromosome 11 (g.61392563 [GRCh38]), 69 base pairs upstream of the start codon of the ciliopathy gene TMEM216 (c.-69G>A, c.

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