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γ-Aminobutyric acid (GABA) is the principal inhibitory neurotransmitter in the adult brain which mediates its rapid effects on neuronal excitability via ionotropic GABAA receptors. GABA levels in the brain are critically dependent upon GABA-aminotransferase (GABA-AT) which promotes its degradation. Vigabatrin, a low-affinity GABA-AT inhibitor, exhibits anticonvulsant efficacy, but its use is limited due to cumulative ocular toxicity. OV329 is a rationally designed, next-generation GABA-AT inhibitor with enhanced potency. We demonstrate that sustained exposure to OV329 in mice reduces GABA-AT activity and subsequently elevates GABA levels in the brain. Parallel increases in the efficacy of GABAergic inhibition were evident, together with elevations in electroencephalographic delta power. Consistent with this, OV329 exposure reduced the severity of status epilepticus and the development of benzodiazepine refractory seizures. Thus, OV329 may be of utility in treating seizure disorders and associated pathologies that result from neuronal hyperexcitability.
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4-Aminobutirato Transaminase , Anticonvulsivantes , Benzodiazepinas , Convulsões , Ácido gama-Aminobutírico , Animais , Anticonvulsivantes/farmacologia , Anticonvulsivantes/administração & dosagem , Masculino , Benzodiazepinas/farmacologia , 4-Aminobutirato Transaminase/antagonistas & inibidores , 4-Aminobutirato Transaminase/metabolismo , Convulsões/tratamento farmacológico , Convulsões/metabolismo , Ácido gama-Aminobutírico/metabolismo , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Inibição Neural/efeitos dos fármacos , Inibição Neural/fisiologia , Camundongos , Eletroencefalografia , Modelos Animais de Doenças , Estado Epiléptico/tratamento farmacológico , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/metabolismo , FemininoRESUMO
LMTK3 is a brain-specific transmembrane serine/threonine protein kinase that acts as a scaffold for protein phosphatase-1 (PP1). Although LMKT3 has been identified as a risk factor for autism and epilepsy, its physiological significance is unknown. Here, we demonstrate that LMTK3 copurifies and binds to KCC2, a neuron-specific K+/Cl- transporter. KCC2 activity is essential for Cl--mediated hyperpolarizing GABAAR receptor currents, the unitary events that underpin fast synaptic inhibition. LMTK3 acts to promote the association of KCC2 with PP1 to promote the dephosphorylation of S940 within its C-terminal cytoplasmic domain, a process the diminishes KCC2 activity. Accordingly, acute inhibition of LMTK3 increases KCC2 activity dependent upon S940 and increases neuronal Cl- extrusion. Consistent with this, LMTK3 inhibition reduced intrinsic neuronal excitability and the severity of seizure-like events in vitro. Thus, LMTK3 may have profound effects on neuronal excitability as an endogenous modulator of KCC2 activity.
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The regiodivergent synthesis of 4- and 5-sulfenyl oxazoles from 1,4,2-dioxazoles and alkynyl thioethers has been achieved. Gold-catalysed conditions are used to favour the formation of 5-sulfenyl oxazoles via ß-selective attack of the nitrenoid relative to the sulfenyl group. In contrast, 4-sulfenyl oxazoles are formed by α-selective reaction under Brønsted acid conditions from the same substrates. The nature of stabilising gold-sulfur interactions have been investigated by natural bond orbital analysis, showing that the SâAu interactions are significantly stronger in the intermediate that favours the 5-sulfenyl oxazoles. A kinetic survey identifies catalyst inhibition processes. This study into the regiodivergent methods includes the development of telescoped annulation-oxidation protocols for regioselective access to oxazole sulfoxides and sulfones.
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[This corrects the article DOI: 10.1371/journal.pone.0253364.].
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INTRODUCTION: Current hospital-based care pathways are generally single-disease centred. As a result, coexisting morbidities are often suboptimally evaluated and managed, a deficiency becoming increasingly apparent among older patients who exhibit heterogeneity in health status, functional abilities, frailty, and other geriatric impairments. To address this issue, our study aims to assess a newly developed patient-centred care pathway for older patients with multimorbidity and cancer. The new care pathway was based on currently available evidence and co-designed by end-users including health care professionals, patients, and informal caregivers. Within this care pathway, all healthcare professionals involved in the care of older patients with multimorbidity and cancer will form a Health Professional Consortium (HPC). The role of the HPC will be to centralise oncologic and non-oncologic treatment recommendations in accordance with the patient's priorities. Moreover, an Advanced Practice Nurse will act as case-manager by being the primary point of contact for the patient, thus improving coordination between specialists, and by organising and leading the consortium. Patient monitoring and the HPC collaboration will be facilitated by digital communication tools designed specifically for this purpose, with the added benefit of being customisable for each patient. MATERIALS AND METHODS: The GERONTE study is a prospective international, multicentric study consisting of two stepped-wedge trials performed at 16 clinical sites across three European countries. Each trial will include 720 patients aged 70 years and over with a new or progressive cancer (breast, lung, colorectal, prostate) and at least one moderate or severe multimorbidity. The patients in the intervention group will receive the new care pathway whereas patients in the control group will receive usual oncologic care. DISCUSSION: GERONTE will evaluate whether this kind of holistic, patient-oriented healthcare management can improve quality of life (primary outcome) and other valuable endpoints in older patients with multimorbidity and cancer. An ancillary study will assess in depth the socio-economic impact of the intervention and deliver concrete implementation guidelines for the GERONTE intervention care pathway. TRIAL REGISTRATION: FRONE: NCT05720910 TWOBE: NCT05423808.
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Multimorbidade , Neoplasias , Assistência Centrada no Paciente , Humanos , Neoplasias/complicações , Neoplasias/terapia , Idoso , Tecnologia da Informação , Procedimentos Clínicos , Saúde Holística , Idoso de 80 Anos ou mais , Masculino , FemininoRESUMO
A polysubstituted 3-aminoimidazo[5,1-b]oxazol-6-ium framework has been accessed from a new nitrenoid reagent by a two-step ynamide annulation and imidazolium ring-formation sequence. Metalation with Au(I), Cu(I) and Ir(I) at the C2 position provides an L-shaped NHC ligand scaffold that has been validated in gold-catalysed alkyne hydration and arylative cyclisation reactions.
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Parkinson's disease (PD) is a progressive neurological disorder that manifests clinically as alterations in movement as well as multiple non-motor symptoms including but not limited to cognitive and autonomic abnormalities. Loss-of-function mutations in the gene encoding the ubiquitin E3 ligase Parkin are causal for familial and juvenile PD. Among several therapeutic approaches being explored to treat or improve the prognosis of patients with PD, the use of small molecules able to reinstate or boost Parkin activity represents a potential pharmacological treatment strategy. A major barrier is the lack of high-throughput platforms for the robust and accurate quantification of Parkin activity in vitro. Here, we present two different and complementary Matrix-Assisted Laser Desorption/Ionization Time-Of-Flight Mass Spectrometry (MALDI-TOF/MS)-based approaches for the quantification of Parkin E3 ligase activity in vitro. Both approaches are scalable for high-throughput primary screening to facilitate the identification of Parkin modulators.
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Doença de Parkinson , Ubiquitina-Proteína Ligases , Humanos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Ubiquitina-Proteína Ligases/genética , Ubiquitinação , Ubiquitina/genética , Mutação , Doença de Parkinson/diagnósticoRESUMO
Background: Stigma contributes to the negative social conditions persons with intellectual disabilities are exposed to, and it needs tackling at multiple levels. Standing Up for Myself is a psychosocial group intervention designed to enable individuals with intellectual disabilities to discuss stigmatising encounters in a safe and supportive setting and to increase their self-efficacy in managing and resisting stigma. Objectives: To adapt Standing Up for Myself to make it suitable as a digital intervention; to evaluate the feasibility and acceptability of Digital Standing Up for Myself and online administration of outcome measures in a pilot; to describe usual practice in the context of the coronavirus disease 2019 pandemic to inform future evaluation. Design: Adaptation work followed by a single-arm pilot of intervention delivery. Setting and participants: Four third and education sector organisations. Individuals with mild-to-moderate intellectual disabilities, aged 16+, members of existing groups, with access to digital platforms. Intervention: Digital Standing Up for Myself intervention. Adapted from face-to-face Standing Up for Myself intervention, delivered over four weekly sessions, plus a 1-month follow-up session. Outcomes: Acceptability and feasibility of delivering Digital Standing Up for Myself and of collecting outcome and health economic measures at baseline and 3 months post baseline. Outcomes are mental well-being, self-esteem, self-efficacy in rejecting prejudice, reactions to discrimination and sense of social power. Results: Adaptation to the intervention required changes to session duration, group size and number of videos; otherwise, the content remained largely the same. Guidance was aligned with digital delivery methods and a new group member booklet was produced. Twenty-two participants provided baseline data. The intervention was started by 21 participants (four groups), all of whom were retained at 3 months. Group facilitators reported delivering the intervention as feasible and suggested some refinements. Fidelity of the intervention was good, with over 90% of key components observed as implemented by facilitators. Both facilitators and group members reported the intervention to be acceptable. Group members reported subjective benefits, including increased confidence, pride and knowing how to deal with difficult situations. Digital collection of all outcome measures was feasible and acceptable, with data completeness ≥ 95% for all measures at both time points. Finally, a picture of usual practice has been developed as an intervention comparator for a future trial. Limitations: The pilot sample was small. It remains unclear whether participants would be willing to be randomised to a treatment as usual arm or whether they could be retained for 12 months follow-up. Conclusions: The target number of groups and participants were recruited, and retention was good. It is feasible and acceptable for group facilitators with some training and supervision to deliver Digital Standing Up for Myself. Further optimisation of the intervention is warranted. Future work: To maximise the acceptability and reach of the intervention, a future trial could offer the adapted Digital Standing Up for Myself, potentially alongside the original face-to-face version of the intervention. Study registration: This study was registered as ISRCTN16056848. Funding: This award was funded by the National Institute for Health and Care Research (NIHR) Public Health Research programme (NIHR award ref: 17/149/03) and is published in full in Public Health Research; Vol. 12, No. 1. See the NIHR Funding and Awards website for further award information.
People with intellectual disabilities (or 'learning disabilities' in United Kingdom language) are more likely to experience poor physical and mental health than the general population. Stigma (negative stereotypes, prejudice and discrimination) has been linked to lower self-esteem, quality of life, and mental and physical ill health. Efforts to empower people with intellectual disabilities themselves to challenge stigma with a view to improving well-being, health and self-esteem are lacking. In 2017, we developed Standing Up for Myself, a brief group-based programme for people with mild-to-moderate intellectual disabilities aged 16+ to address this gap. As this study got underway, face-to-face meetings were suspended due to the coronavirus disease 2019 pandemic. We used the opportunity to assess whether Standing Up for Myself could be delivered through web-based meetings. We adapted Standing Up for Myself for digital delivery, with close input from advisors with intellectual disabilities and experienced group facilitators. We then tested the digital version in charity and education settings to evaluate if Digital Standing Up for Myself could be delivered as planned and how acceptable it was to group facilitators and participants. Four groups, with a total of 22 members, signed up to try Digital Standing Up for Myself. One participant dropped out before starting Standing Up for Myself, and the other 21 continued until the end of the programme. Retention and attendance were good; participants on average attended four of the five sessions. Ninety per cent of the core programme requirements were fully delivered as detailed in the Digital Standing Up for Myself manual. Problems with technology were manageable, although facilitators found using the Standing Up for Myself Wiki platform (an online platform for storage and sharing of resources) difficult, particularly when sharing video content. Facilitators felt acceptable levels of privacy were achieved and there were no reports of undue distress. All facilitators and many group members said they would recommend Digital Standing Up for Myself to others. Group members shared how the programme benefitted them, noting increased awareness about disabilities, and for some increased confidence, pride and independence. Some had learnt how to stand up for themselves and manage difficult situations and took pride in this. Completing outcome and health cost measures via web-based meetings was acceptable and data were largely fully complete and useable.
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Deficiência Intelectual , Humanos , Adulto , Adolescente , Estudos de Viabilidade , Avaliação de Resultados em Cuidados de Saúde , Autoeficácia , EmoçõesRESUMO
The Concise Guide to PHARMACOLOGY 2023/24 is the sixth in this series of biennial publications. The Concise Guide provides concise overviews, mostly in tabular format, of the key properties of approximately 1800 drug targets, and over 6000 interactions with about 3900 ligands. There is an emphasis on selective pharmacology (where available), plus links to the open access knowledgebase source of drug targets and their ligands (https://www.guidetopharmacology.org/), which provides more detailed views of target and ligand properties. Although the Concise Guide constitutes almost 500 pages, the material presented is substantially reduced compared to information and links presented on the website. It provides a permanent, citable, point-in-time record that will survive database updates. The full contents of this section can be found at http://onlinelibrary.wiley.com/doi/10.1111/bph.16178. Ion channels are one of the six major pharmacological targets into which the Guide is divided, with the others being: G protein-coupled receptors, nuclear hormone receptors, catalytic receptors, enzymes and transporters. These are presented with nomenclature guidance and summary information on the best available pharmacological tools, alongside key references and suggestions for further reading. The landscape format of the Concise Guide is designed to facilitate comparison of related targets from material contemporary to mid-2023, and supersedes data presented in the 2021/22, 2019/20, 2017/18, 2015/16 and 2013/14 Concise Guides and previous Guides to Receptors and Channels. It is produced in close conjunction with the Nomenclature and Standards Committee of the International Union of Basic and Clinical Pharmacology (NC-IUPHAR), therefore, providing official IUPHAR classification and nomenclature for human drug targets, where appropriate.
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Bases de Dados de Produtos Farmacêuticos , Farmacologia , Humanos , Canais Iônicos/química , Ligantes , Receptores Acoplados a Proteínas G , Bases de Dados FactuaisRESUMO
Hydrogenation is a catalytic process that has the potential to facilitate sustainable chemical production. In this work, a model monoaromatic hydrocarbon, phenyldodecane (PDD), comprising an aromatic ring with a long aliphatic side chain has been chosen as representative of a typical species involved in hydrogenation and hydrocracked at a high pressure and temperature over a platinum catalyst in a bespoke benchtop mini-reactor. Gas chromatography-mass spectrometry (GC-MS), Fourier transform infrared (FTIR) spectroscopy, UV-vis spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy were employed to analyze the changes that took place after hydrocracking for different time periods. By combining the results from these sensitive spectroscopic tools, it was found that along with the saturation of the aromatic ring of PDD by hydrogen addition, new molecules were formed via ring opening and catalytic cracking. For comparison purposes, the spectra of the samples post hydrogenation were compared with those of cyclohexylnonadecane (CHND), which has a saturated six-membered ring and a long aliphatic tail.
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Skilful predictions of near-term climate extremes are key to a resilient society. However, standard methods of analysing seasonal forecasts are not optimised to identify the rarer and most impactful extremes. For example, standard tercile probability maps, used in real-time regional climate outlooks, failed to convey the extreme magnitude of summer 2022 Pakistan rainfall that was, in fact, widely predicted by seasonal forecasts. Here we argue that, in this case, a strong summer La Niña provided a window of opportunity to issue a much more confident forecast for extreme rainfall than average skill estimates would suggest. We explore ways of building forecast confidence via a physical understanding of dynamical mechanisms, perturbation experiments to isolate extreme drivers, and simple empirical relationships. We highlight the need for more detailed routine monitoring of forecasts, with improved tools, to identify regional climate extremes and hence utilise windows of opportunity to issue trustworthy and actionable early warnings.
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In vitro investigations of host-virus interactions are reliant on suitable cell and tissue culture models. Results are only as good as the model they are generated in. However, choosing cell models for in vitro work often depends on availability and previous use alone. Despite the vast increase in coronavirus research over the past few years, scientists are still heavily reliant on: non-human, highly heterogeneous or not fully differentiated, or naturally unsusceptible cells requiring overexpression of receptors and other accessory factors. Complex primary or stem cell models are highly representative of human tissues but are expensive and time-consuming to develop and maintain with limited suitability for high-throughput experiments.Using tissue-specific expression patterns, we identified human kidney cells as an ideal target for severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and broader coronavirus infection. We show the use of the well-characterized human kidney cell line Caki-1 for infection with three human coronaviruses (hCoVs): Betacoronaviruses SARS-CoV-2 and Middle Eastern respiratory syndrome coronavirus and Alphacoronavirus hCoV 229E. Caki-1 cells show equal or superior susceptibility to all three coronaviruses when compared to other commonly used cell lines for the cultivation of the respective virus. Antibody staining against SARS-CoV-2 N protein shows comparable replication rates. A panel of 26 custom antibodies shows the location of SARS-CoV-2 proteins during replication using immunocytochemistry. In addition, Caki-1 cells were found to be susceptible to two other human respiratory viruses, influenza A virus and respiratory syncytial virus, making them an ideal model for cross-comparison for a broad range of respiratory viruses. IMPORTANCE Cell lines remain the backbone of virus research, but results are only as good as their originating model. Despite increased research into human coronaviruses following the COVID-19 pandemic, researchers continue to rely on suboptimal cell line models of: non-human origin, incomplete differentiation, or lacking active interferon responses. We identified the human kidney Caki-1 cell line as a potential target for severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). This cell line could be shown to be infectable with a wide range of coronaviruses including common cold virus hCoV-229E, epidemic virus MERS-CoV, and SARS-CoV-2 as well as other important respiratory viruses influenza A virus and respiratory syncytial virus. We could show the localization of 26 SARS-CoV-2 proteins in Caki-1 cells during natural replication and the cells are competent of forming a cellular immune response. Together, this makes Caki-1 cells a unique tool for cross-virus comparison in one cell line.
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Linhagem Celular , Infecções por Coronaviridae , Coronaviridae , Humanos , Coronaviridae/fisiologia , Rim/citologia , Pandemias , Infecções por Coronaviridae/patologia , Infecções por Coronaviridae/virologiaRESUMO
The discovery of disease-modifying therapies for Parkinson's Disease (PD) represents a critical need in neurodegenerative medicine. Genetic mutations in leucine-rich repeat kinase 2 (LRRK2) are risk factors for the development of PD, and some of these mutations have been linked to increased LRRK2 kinase activity and neuronal toxicity in cellular and animal models. Furthermore, LRRK2 function as a scaffolding protein in several pathways has been implicated as a plausible mechanism underlying neurodegeneration caused by LRRK2 mutations. Given that both the kinase activity and scaffolding function of LRRK2 have been linked to neurodegeneration, we developed proteolysis-targeting chimeras (PROTACs) targeting LRRK2. The degrader molecule JH-XII-03-02 (6) displayed high potency and remarkable selectivity for LRKK2 when assessed in a of 468 panel kinases and serves the dual purpose of eliminating both the kinase activity as well as the scaffolding function of LRRK2.
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Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina , Doença de Parkinson , Animais , Modelos Animais , Mutação , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/genética , Fosforilação , Quimera de Direcionamento de Proteólise , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/antagonistas & inibidoresRESUMO
Plant receptor kinases are key transducers of extracellular stimuli, such as the presence of beneficial or pathogenic microbes or secreted signaling molecules. Receptor kinases are regulated by numerous post-translational modifications.1,2,3 Here, using the immune receptor kinases FLS24 and EFR,5 we show that S-acylation at a cysteine conserved in all plant receptor kinases is crucial for function. S-acylation involves the addition of long-chain fatty acids to cysteine residues within proteins, altering their biochemical properties and behavior within the membrane environment.6 We observe S-acylation of FLS2 at C-terminal kinase domain cysteine residues within minutes following the perception of its ligand, flg22, in a BAK1 co-receptor and PUB12/13 ubiquitin ligase-dependent manner. We demonstrate that S-acylation is essential for FLS2-mediated immune signaling and resistance to bacterial infection. Similarly, mutating the corresponding conserved cysteine residue in EFR suppressed elf18-triggered signaling. Analysis of unstimulated and activated FLS2-containing complexes using microscopy, detergents, and native membrane DIBMA nanodiscs indicates that S-acylation stabilizes, and promotes retention of, activated receptor kinase complexes at the plasma membrane to increase signaling efficiency.
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Proteínas de Arabidopsis , Arabidopsis , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Ligantes , Cisteína/metabolismo , Plantas/metabolismo , Membrana Celular/metabolismo , Acilação , Imunidade VegetalRESUMO
Fast synaptic inhibition is dependent on targeting specific GABAAR subtypes to dendritic and axon initial segment (AIS) synapses. Synaptic GABAARs are typically assembled from α1-3, ß and γ subunits. Here, we isolate distinct GABAARs from the brain and interrogate their composition using quantitative proteomics. We show that α2-containing receptors co-assemble with α1 subunits, whereas α1 receptors can form GABAARs with α1 as the sole α subunit. We demonstrate that α1 and α2 subunit-containing receptors co-purify with distinct spectrin isoforms; cytoskeletal proteins that link transmembrane proteins to the cytoskeleton. ß2-spectrin was preferentially associated with α1-containing GABAARs at dendritic synapses, while ß4-spectrin was associated with α2-containing GABAARs at AIS synapses. Ablating ß2-spectrin expression reduced dendritic and AIS synapses containing α1 but increased the number of synapses containing α2, which altered phasic inhibition. Thus, we demonstrate a role for spectrins in the synapse-specific targeting of GABAARs, determining the efficacy of fast neuronal inhibition.
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Receptores de GABA-A , Espectrina , Receptores de GABA-A/metabolismo , Espectrina/metabolismo , Sinapses/metabolismo , Proteínas de Membrana/metabolismo , Ácido gama-Aminobutírico/metabolismoRESUMO
Ubiquitylation (or ubiquitination) is the reversible conjugation of a 76-amino-acid polypeptide (ubiquitin) to a target protein to modulate various biological processes. Deubiquitylating enzymes (DUBs) are a class of enzymes that specifically remove ubiquitin from a substrate. In recent years DUBs have garnered significant attention as a new class of targets in multiple therapeutic areas. The recent development of high-throughput Matrix-Assisted Laser Desorption/Ionization-Time of Flight mass spectrometry (MALDI-TOF MS) has provided new tools to perform drug discovery screening. Here we present a facile and high-throughput step-by-step protocol of the MALDI-TOF MS-based DUB assay for screening the activity of DUBs in vitro. In a MALDI-TOF DUB assay, we quantitate the amount of mono-ubiquitin generated by the in vitro cleavage of ubiquitin chains. The presented protocol takes advantage of nanoliter dispensing robotics and automated MALDI-TOF MS analysis to screen large and diverse compound libraries.
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Descoberta de Drogas , Ensaios de Triagem em Larga Escala , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Ensaios de Triagem em Larga Escala/métodos , Descoberta de Drogas/métodos , Ubiquitina/metabolismo , Ensaios EnzimáticosRESUMO
It may be that habitable planets are common but life is rare. If future advances in telescopes increasingly suggest this is so, humankind might feel motivated to seed lifeless planets with resilient terrestrial organisms or synthetic forms designed to thrive on the target planet. A useful mechanism for achieving this goal at a relatively low cost is to use interstellar comets transiting the Solar System to convey microbial cargoes toward nearby planetary systems, where they could disseminate the inoculum via their dust trails. Conversely, it is conceivable that terrestrial life was deliberately seeded in this matter, a hypothesis that could be tested if we found evidence for life on other Solar System bodies that displayed common basic biochemical signatures. Our scenario raises a number of ethical and technological challenges that need to be addressed.
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Impaired inhibitory signaling underlies the pathophysiology of many neuropsychiatric and neurodevelopmental disorders including autism spectrum disorders and epilepsy. Neuronal inhibition is regulated by synaptic and extrasynaptic γ-aminobutyric acid type A receptors (GABA A Rs), which mediate phasic and tonic inhibition, respectively. These two GABA A R subtypes differ in their function, ligand sensitivity, and physiological properties. Importantly, they contain different α subunit isoforms: synaptic GABA A Rs contain the α1-3 subunits whereas extrasynaptic GABA A Rs contain the α4-6 subunits. While the subunit composition is critical for the distinct roles of synaptic and extrasynaptic GABA A R subtypes in inhibition, the molecular mechanism of the subtype-specific assembly has not been elucidated. To address this issue, we purified endogenous α1- and α4-containing GABA A Rs from adult murine forebrains and examined their subunit composition and interacting proteins using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) and quantitative analysis. We found that the α1 and α4 subunits form separate populations of GABA A Rs and interact with distinct sets of binding proteins. We also discovered that the ß3 subunit, which co-purifies with both the α1 and α4 subunits, has different levels of phosphorylation on serines 408 and 409 (S408/9) between the two receptor subtypes. To understand the role S408/9 plays in the assembly of α1- and α4-containing GABA A Rs, we examined the effects of S408/9A (alanine) knock-in mutation on the subunit composition of the two receptor subtypes using LC-MS/MS and quantitative analysis. We discovered that the S408/9A mutation results in the formation of novel α1α4-containing GABA A Rs. Moreover, in S408/9A mutants, the plasma membrane expression of the α4 subunit is increased whereas its retention in the endoplasmic reticulum is reduced. These findings suggest that S408/9 play a critical role in determining the subtype-specific assembly of GABA A Rs, and thus the efficacy of neuronal inhibition.
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PURPOSE: This study assesses postoperative quality-of-life outcomes via the Glasgow Benefit Inventory (GBI) in patients undergoing transnasal endoscopic pituitary surgery for pituitary adenoma. METHODS: This was a retrospective cohort study in a UK tertiary referral centre. 145 patients who had undergone transnasal endoscopic pituitary surgery for pituitary adenoma over a 6-year period at one institution completed the GBI with at least 3 months' follow up. Patients with prior radiotherapy were excluded. The GBI is a patient-reported outcome measure that assesses post-intervention outcomes in three domains: 'general' functioning, 'social support' and 'physical' functioning. Pre- and post-operative visual loss scores were additionally assessed via a 1-5 Likert scale. GBI scores were assessed alongside these visual loss scores, clinical and surgical parameters and demographics. RESULTS: Mean age was 59.5 years (range 20-87 years) and mean follow up was 36 months. A total of 46 of 145 (31.7%) patients had secreting tumours. The most common primary symptom was visual loss. Mean total score for all patients was positive (+8.4); with 'general' domain score the most positive (+10.5). All patient groups had overall positive, 'general' and 'social support' domain scores. Patients with Cushing's disease reported significantly higher mean total scores (+29.6) than all other groups. Acromegaly (+7.9) and non-functioning adenoma (NFA) groups (+5.2) reported lower mean total scores. 'Physical' domain mean scores were negative for acromegaly and NFA groups. There was statistical significance between a pre- to post-operative improvement in visual score and mean total GBI score (p = 0.02) and mean 'general' domain GBI score (p = 0.02). CONCLUSIONS: These findings can aid preoperative counselling of patients undergoing this surgery. Those with NFA and no anticipated improvement to visual loss symptoms may be advised of possible worsened physical outcomes and of the option to delay the surgery until symptoms are present.