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1.
EMBO Mol Med ; 14(9): e15829, 2022 09 07.
Article in English | MEDLINE | ID: mdl-35916241

ABSTRACT

Whole-exome sequencing of two patients with idiopathic complex neurodevelopmental disorder (NDD) identified biallelic variants of unknown significance within FIBCD1, encoding an endocytic acetyl group-binding transmembrane receptor with no known function in the central nervous system. We found that FIBCD1 preferentially binds and endocytoses glycosaminoglycan (GAG) chondroitin sulphate-4S (CS-4S) and regulates GAG content of the brain extracellular matrix (ECM). In silico molecular simulation studies and GAG binding analyses of patient variants determined that such variants are loss-of-function by disrupting FIBCD1-CS-4S association. Gene knockdown in flies resulted in morphological disruption of the neuromuscular junction and motor-related behavioural deficits. In humans and mice, FIBCD1 is expressed in discrete brain regions, including the hippocampus. Fibcd1 KO mice exhibited normal hippocampal neuronal morphology but impaired hippocampal-dependent learning. Further, hippocampal synaptic remodelling in acute slices from Fibcd1 KO mice was deficient but restored upon enzymatically modulating the ECM. Together, we identified FIBCD1 as an endocytic receptor for GAGs in the brain ECM and a novel gene associated with an NDD, revealing a critical role in nervous system structure, function and plasticity.


Subject(s)
Neurodevelopmental Disorders , Receptors, Cell Surface , Animals , Humans , Mice , Endocytosis , Extracellular Matrix/metabolism , Neurodevelopmental Disorders/genetics , Receptors, Cell Surface/metabolism
2.
FEBS J ; 289(12): 3457-3476, 2022 06.
Article in English | MEDLINE | ID: mdl-35029322

ABSTRACT

Mesenchyme homeobox protein 2 (MEOX2) is a transcription factor involved in mesoderm differentiation, including development of bones, muscles, vasculature and dermatomes. We have previously identified dysregulation of MEOX2 in fibroblasts from Congenital Insensitivity to Pain patients, and confirmed that btn, the Drosophila homologue of MEOX2, plays a role in nocifensive responses to noxious heat stimuli. To determine the importance of MEOX2 in the mammalian peripheral nervous system, we used a Meox2 heterozygous (Meox2+/- ) mouse model to characterise its function in the sensory nervous system, and more specifically, in nociception. MEOX2 is expressed in the mouse dorsal root ganglia (DRG) and spinal cord, and localises in the nuclei of a subset of sensory neurons. Functional studies of the mouse model, including behavioural, cellular and electrophysiological analyses, showed altered nociception encompassing impaired action potential initiation upon depolarisation. Mechanistically, we noted decreased expression of Scn9a and Scn11a genes encoding Nav 1.7 and Nav 1.9 voltage-gated sodium channels respectively, that are crucial in subthreshold amplification and action potential initiation in nociceptors. Further transcriptomic analyses of Meox2+/- DRG revealed downregulation of a specific subset of genes including those previously associated with pain perception, such as PENK and NPY. Based on these observations, we propose a novel role of MEOX2 in primary afferent nociceptor neurons for the maintenance of a transcriptional programme required for proper perception of acute and inflammatory noxious stimuli.


Subject(s)
Homeodomain Proteins , Nociceptors , Animals , Ganglia, Spinal/metabolism , Homeodomain Proteins/genetics , Homeodomain Proteins/metabolism , Humans , Mesoderm/metabolism , Mice , NAV1.7 Voltage-Gated Sodium Channel/genetics , NAV1.9 Voltage-Gated Sodium Channel/metabolism , Nociceptors/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism
3.
Bioinformatics ; 38(6): 1692-1699, 2022 03 04.
Article in English | MEDLINE | ID: mdl-34935929

ABSTRACT

MOTIVATION: High-content imaging screens provide a cost-effective and scalable way to assess cell states across diverse experimental conditions. The analysis of the acquired microscopy images involves assembling and curating raw cellular measurements into morphological profiles suitable for testing biological hypotheses. Despite being a critical step, general-purpose and adaptable tools for morphological profiling are lacking and no solution is available for the high-performance Julia programming language. RESULTS: Here, we introduce BioProfiling.jl, an efficient end-to-end solution for compiling and filtering informative morphological profiles in Julia. The package contains all the necessary data structures to curate morphological measurements and helper functions to transform, normalize and visualize profiles. Robust statistical distances and permutation tests enable quantification of the significance of the observed changes despite the high fraction of outliers inherent to high-content screens. This package also simplifies visual artifact diagnostics, thus streamlining a bottleneck of morphological analyses. We showcase the features of the package by analyzing a chemical imaging screen, in which the morphological profiles prove to be informative about the compounds' mechanisms of action and can be conveniently integrated with the network localization of molecular targets. AVAILABILITY AND IMPLEMENTATION: The Julia package is available on GitHub: https://github.com/menchelab/BioProfiling.jl. We also provide Jupyter notebooks reproducing our analyses: https://github.com/menchelab/BioProfilingNotebooks. The data underlying this article are available from FigShare, at https://doi.org/10.6084/m9.figshare.14784678.v2. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Subject(s)
Programming Languages , Software , Microscopy
4.
Front Mol Neurosci ; 14: 720973, 2021.
Article in English | MEDLINE | ID: mdl-34646120

ABSTRACT

PR domain-containing member 12 (PRDM12) is a key developmental transcription factor in sensory neuronal specification and survival. Patients with rare deleterious variants in PRDM12 are born with congenital insensitivity to pain (CIP) due to the complete absence of a subtype of peripheral neurons that detect pain. In this paper, we report two additional CIP cases with a novel homozygous PRDM12 variant. To elucidate the function of PRDM12 during mammalian development and adulthood, we generated temporal and spatial conditional mouse models. We find that PRDM12 is expressed throughout the adult nervous system. We observed that loss of PRDM12 during mid-sensory neurogenesis but not in the adult leads to reduced survival. Comparing cellular biophysical nociceptive properties in developmental and adult-onset PRDM12 deletion mouse models, we find that PRDM12 is necessary for proper nociceptive responses throughout life. However, we find that PRDM12 regulates distinct age-dependent transcriptional programs. Together, our results implicate PRDM12 as a viable therapeutic target for specific pain therapies even in adults.

5.
Trends Mol Med ; 27(3): 220-230, 2021 03.
Article in English | MEDLINE | ID: mdl-33397633

ABSTRACT

Intellectual disabilities (ID) are a type of neurodevelopmental disorder (NDD). They can have a genetic cause, including an emerging class of ID centring around Rho GTPases, such as Ras-related C3 botulinum toxin substrate 1 (RAC1). Guidelines for establishing genetic causality include the use of cellular models, which often have morphological aberrations, a long-standing hallmark of ID. Disease cellular models can facilitate high-throughput screening (HTS) of chemical or genetic perturbations, which can provide translatable biological insight. Here, we discuss a class of IDs centring around RAC1. We review novel and established cellular models of ID, including mouse and human primary cells and reprogrammed or induced neurons. Finally, we review progress and remaining challenges in the adoption of HTS methodologies by the community studying neurological disorders.


Subject(s)
Intellectual Disability/genetics , rac1 GTP-Binding Protein , Animals , Cell Culture Techniques , High-Throughput Screening Assays/methods , Humans , Mice , Neurodevelopmental Disorders/genetics , Neurons/metabolism , rac1 GTP-Binding Protein/genetics , rac1 GTP-Binding Protein/metabolism , rho GTP-Binding Proteins
6.
Br J Gen Pract ; 69(687): e689-e696, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31455643

ABSTRACT

BACKGROUND: Financial incentives in the UK such as the Quality and Outcomes Framework (QOF) reward GP surgeries for achievement of nationally defined targets. These have shown mixed results, with weak evidence for some measures, but also possible unintended negative effects. AIM: To look at the effects of a local intervention for atrial fibrillation (AF) and hypertension, with surgeries rewarded financially for work, including appointing designated practice leads, attendance at peer review workshops, and producing their own protocols. DESIGN AND SETTING: A controlled before-after study comparing surgery performance measures in UK primary care. METHOD: This study used published QOF data to analyse changes from baseline in mean scores per surgery relating to AF and hypertension prevalence and management at T1 (12 months) and T2 (24 months) for the intervention group, which consisted of all 58 surgeries in East Lancashire Clinical Commissioning Group (CCG), compared to the control group, which consisted of all other surgeries in north-west England. RESULTS: There was a small acceleration between T0 (baseline) and T2 in recorded prevalence of hypertension in the intervention group compared to the controls, difference 0.29% (95% confidence interval [CI] = 0.05 to 0.53), P = 0.017, but AF prevalence did not increase more in the intervention group. Improvement in quality of management of AF was significantly better in the intervention group, difference 3.24% (95% CI = 1.37 to 5.12), P = 0.001. CONCLUSION: This intervention improved diagnosis rates of hypertension but not AF, though it did improve quality of AF management. It indicates that funded time to develop quality-improvement measures targeted at a local population and involving peer support can engage staff and have the potential to improve quality.


Subject(s)
Atrial Fibrillation/diagnosis , Atrial Fibrillation/therapy , General Practice , Hypertension/diagnosis , Hypertension/therapy , Motivation , Primary Health Care/standards , Quality Improvement , Quality of Health Care , Adult , Aged , Controlled Before-After Studies , Disease Management , Female , Humans , Male , Middle Aged , United Kingdom
7.
Med Educ Online ; 22(1): 1272838, 2017.
Article in English | MEDLINE | ID: mdl-28178920

ABSTRACT

BACKGROUND: Healthcare increasingly recognises and focusses on the phenomena of 'safe practice' and 'patient safety.' Success with non-technical skills (NTS) training in other industries has led to widespread transposition to healthcare education, with communication and teamwork skills central to NTS frameworks. OBJECTIVE: This study set out to identify how the context of interprofessional simulation learning influences NTS acquisition and development of 'safety' amongst learners. METHODS: Participants receiving a non-technical skills (NTS) safety focussed training package were invited to take part in a focus group interview which set out to explore communication, teamwork, and the phenomenon of safety in the context of the learning experiences they had within the training programme. The analysis was aligned with a constructivist paradigm and took an interactive methodological approach. The analysis proceeded through three stages, consisting of open, axial, and selective coding, with constant comparisons taking place throughout each phase. Each stage provided categories that could be used to explore the themes of the data. Additionally, to ensure thematic saturation, transcripts of observed simulated learning encounters were then analysed. RESULTS: Six themes were established at the axial coding level, i.e., analytical skills, personal behaviours, communication, teamwork, context, and pedagogy. Underlying these themes, two principal concepts emerged, namely: intergroup contact anxiety - as both a result of and determinant of communication - and teamwork, both of which must be considered in relation to context. These concepts have subsequently been used to propose a framework for NTS learning. CONCLUSIONS: This study highlights the role of intergroup contact anxiety and teamwork as factors in NTS behaviour and its dissipation through interprofessional simulation learning. Therefore, this should be a key consideration in NTS education. Future research is needed to consider the role of the affective non-technical attributes of intergroup contact anxiety and teamwork as focuses for education and determinants of safe behaviour. ABBREVIATIONS: AUM: Anxiety/uncertainty management; NTS: Non-technical skills; TINSELS: Training in non-technical skills to enhance levels of medicines safety.


Subject(s)
Communication , Health Personnel/education , Interprofessional Relations , Patient Care Team/organization & administration , Simulation Training/organization & administration , Behavior , Clinical Competence , Group Processes , Humans , Leadership , Qualitative Research
8.
ACS Appl Mater Interfaces ; 8(32): 20928-37, 2016 Aug 17.
Article in English | MEDLINE | ID: mdl-27456294

ABSTRACT

Energy transfer has been identified as an important process in ternary organic solar cells. Here, we develop kinetic Monte Carlo (KMC) models to assess the impact of energy transfer in ternary and binary bulk heterojunction systems. We used fluorescence and absorption spectroscopy to determine the energy disorder and Förster radii for poly(3-hexylthiophene-2,5-diyl), [6,6]-phenyl-C61-butyric acid methyl ester, 4-bis[4-(N,N-diisobutylamino)-2,6-dihydroxyphenyl]squaraine (DIBSq), and poly(2,5-thiophene-alt-4,9-bis(2-hexyldecyl)-4,9-dihydrodithieno[3,2-c:3',2'-h][1,5]naphthyridine-5,10-dione). Heterogeneous energy transfer is found to be crucial in the exciton dissociation process of both binary and ternary organic semiconductor systems. Circumstances favoring energy transfer across interfaces allow relaxation of the electronic energy level requirements, meaning that a cascade structure is not required for efficient ternary organic solar cells. We explain how energy transfer can be exploited to eliminate additional energy losses in ternary bulk heterojunction solar cells, thus increasing their open-circuit voltage without loss in short-circuit current. In particular, we show that it is important that the DIBSq is located at the electron donor-acceptor interface; otherwise charge carriers will be trapped in the DIBSq domain or excitons in the DIBSq domains will not be able to dissociate efficiently at an interface. KMC modeling shows that only small amounts of DIBSq (<5% by weight) are needed to achieve substantial performance improvements due to long-range energy transfer.

9.
Sci Rep ; 6: 24972, 2016 04 26.
Article in English | MEDLINE | ID: mdl-27113558

ABSTRACT

Solar photovoltaics (PV) are emerging as a major alternative energy source. The cost of PV electricity depends on the efficiency of conversion of light to electricity. Despite of steady growth in the efficiency for several decades, little has been achieved to reduce the impact of real-world operating temperatures on this efficiency. Here we demonstrate a highly efficient cooling solution to the recently emerging high performance plasmonic solar cell technology by integrating an advanced nano-coated heat-pipe plate. This thermal cooling technology, efficient for both summer and winter time, demonstrates the heat transportation capability up to ten times higher than those of the metal plate and the conventional wickless heat-pipe plates. The reduction in temperature rise of the plasmonic solar cells operating under one sun condition can be as high as 46%, leading to an approximate 56% recovery in efficiency, which dramatically increases the energy yield of the plasmonic solar cells. This newly-developed, thermally-managed plasmonic solar cell device significantly extends the application scope of PV for highly efficient solar energy conversion.

10.
Angew Chem Int Ed Engl ; 54(5): 1490-3, 2015 Jan 26.
Article in English | MEDLINE | ID: mdl-25504807

ABSTRACT

Tin is a promising anode candidate for next-generation lithium-ion batteries with a high energy density, but suffers from the huge volume change (ca. 260 %) upon lithiation. To address this issue, here we report a new hierarchical tin/carbon composite in which some of the nanosized Sn particles are anchored on the tips of carbon nanotubes (CNTs) that are rooted on the exterior surfaces of micro-sized hollow carbon cubes while other Sn nanoparticles are encapsulated in hollow carbon cubes. Such a hierarchical structure possesses a robust framework with rich voids, which allows Sn to alleviate its mechanical strain without forming cracks and pulverization upon lithiation/de-lithiation. As a result, the Sn/C composite exhibits an excellent cyclic performance, namely, retaining a capacity of 537 mAh g(-1) for around 1000 cycles without obvious decay at a high current density of 3000 mA g(-1) .

12.
Int J Mol Sci ; 13(12): 17019-47, 2012 Dec 12.
Article in English | MEDLINE | ID: mdl-23235328

ABSTRACT

Organic solar cells have the potential to become a low-cost sustainable energy source. Understanding the photoconversion mechanism is key to the design of efficient organic solar cells. In this review, we discuss the processes involved in the photo-electron conversion mechanism, which may be subdivided into exciton harvesting, exciton transport, exciton dissociation, charge transport and extraction stages. In particular, we focus on the role of energy transfer as described by F¨orster resonance energy transfer (FRET) theory in the photoconversion mechanism. FRET plays a major role in exciton transport, harvesting and dissociation. The spectral absorption range of organic solar cells may be extended using sensitizers that efficiently transfer absorbed energy to the photoactive materials. The limitations of F¨orster theory to accurately calculate energy transfer rates are discussed. Energy transfer is the first step of an efficient two-step exciton dissociation process and may also be used to preferentially transport excitons to the heterointerface, where efficient exciton dissociation may occur. However, FRET also competes with charge transfer at the heterointerface turning it in a potential loss mechanism. An energy cascade comprising both energy transfer and charge transfer may aid in separating charges and is briefly discussed. Considering the extent to which the photo-electron conversion efficiency is governed by energy transfer, optimisation of this process offers the prospect of improved organic photovoltaic performance and thus aids in realising the potential of organic solar cells.


Subject(s)
Fluorescence Resonance Energy Transfer , Solar Energy
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