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1.
Cell ; 185(18): 3408-3425.e29, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35985322

RESUMO

Genetically encoded voltage indicators are emerging tools for monitoring voltage dynamics with cell-type specificity. However, current indicators enable a narrow range of applications due to poor performance under two-photon microscopy, a method of choice for deep-tissue recording. To improve indicators, we developed a multiparameter high-throughput platform to optimize voltage indicators for two-photon microscopy. Using this system, we identified JEDI-2P, an indicator that is faster, brighter, and more sensitive and photostable than its predecessors. We demonstrate that JEDI-2P can report light-evoked responses in axonal termini of Drosophila interneurons and the dendrites and somata of amacrine cells of isolated mouse retina. JEDI-2P can also optically record the voltage dynamics of individual cortical neurons in awake behaving mice for more than 30 min using both resonant-scanning and ULoVE random-access microscopy. Finally, ULoVE recording of JEDI-2P can robustly detect spikes at depths exceeding 400 µm and report voltage correlations in pairs of neurons.


Assuntos
Microscopia , Neurônios , Animais , Interneurônios , Camundongos , Microscopia/métodos , Neurônios/fisiologia , Fótons , Vigília
2.
Cell ; 185(6): 1082-1100.e24, 2022 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-35216674

RESUMO

We assembled a semi-automated reconstruction of L2/3 mouse primary visual cortex from ∼250 × 140 × 90 µm3 of electron microscopic images, including pyramidal and non-pyramidal neurons, astrocytes, microglia, oligodendrocytes and precursors, pericytes, vasculature, nuclei, mitochondria, and synapses. Visual responses of a subset of pyramidal cells are included. The data are publicly available, along with tools for programmatic and three-dimensional interactive access. Brief vignettes illustrate the breadth of potential applications relating structure to function in cortical circuits and neuronal cell biology. Mitochondria and synapse organization are characterized as a function of path length from the soma. Pyramidal connectivity motif frequencies are predicted accurately using a configuration model of random graphs. Pyramidal cells receiving more connections from nearby cells exhibit stronger and more reliable visual responses. Sample code shows data access and analysis.


Assuntos
Neocórtex , Animais , Camundongos , Microscopia Eletrônica , Neocórtex/fisiologia , Organelas , Células Piramidais/fisiologia , Sinapses/fisiologia
3.
Cell ; 184(1): 106-119.e14, 2021 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-33333024

RESUMO

The Coronaviridae are a family of viruses that cause disease in humans ranging from mild respiratory infection to potentially lethal acute respiratory distress syndrome. Finding host factors common to multiple coronaviruses could facilitate the development of therapies to combat current and future coronavirus pandemics. Here, we conducted genome-wide CRISPR screens in cells infected by SARS-CoV-2 as well as two seasonally circulating common cold coronaviruses, OC43 and 229E. This approach correctly identified the distinct viral entry factors ACE2 (for SARS-CoV-2), aminopeptidase N (for 229E), and glycosaminoglycans (for OC43). Additionally, we identified phosphatidylinositol phosphate biosynthesis and cholesterol homeostasis as critical host pathways supporting infection by all three coronaviruses. By contrast, the lysosomal protein TMEM106B appeared unique to SARS-CoV-2 infection. Pharmacological inhibition of phosphatidylinositol kinases and cholesterol homeostasis reduced replication of all three coronaviruses. These findings offer important insights for the understanding of the coronavirus life cycle and the development of host-directed therapies.


Assuntos
COVID-19/genética , Infecções por Coronavirus/genética , Coronavirus/fisiologia , Estudo de Associação Genômica Ampla , Interações Hospedeiro-Patógeno , SARS-CoV-2/fisiologia , Células A549 , Animais , Vias Biossintéticas/efeitos dos fármacos , COVID-19/virologia , Linhagem Celular , Chlorocebus aethiops , Colesterol/biossíntese , Colesterol/metabolismo , Análise por Conglomerados , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Resfriado Comum/genética , Resfriado Comum/virologia , Coronavirus/classificação , Infecções por Coronavirus/virologia , Técnicas de Inativação de Genes , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Humanos , Camundongos , Fosfatidilinositóis/biossíntese , Células Vero , Internalização do Vírus/efeitos dos fármacos , Replicação Viral
4.
Cell ; 184(2): 323-333.e9, 2021 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-33306959

RESUMO

The December 2019 outbreak of a novel respiratory virus, SARS-CoV-2, has become an ongoing global pandemic due in part to the challenge of identifying symptomatic, asymptomatic, and pre-symptomatic carriers of the virus. CRISPR diagnostics can augment gold-standard PCR-based testing if they can be made rapid, portable, and accurate. Here, we report the development of an amplification-free CRISPR-Cas13a assay for direct detection of SARS-CoV-2 from nasal swab RNA that can be read with a mobile phone microscope. The assay achieved ∼100 copies/µL sensitivity in under 30 min of measurement time and accurately detected pre-extracted RNA from a set of positive clinical samples in under 5 min. We combined crRNAs targeting SARS-CoV-2 RNA to improve sensitivity and specificity and directly quantified viral load using enzyme kinetics. Integrated with a reader device based on a mobile phone, this assay has the potential to enable rapid, low-cost, point-of-care screening for SARS-CoV-2.


Assuntos
Teste de Ácido Nucleico para COVID-19/métodos , Telefone Celular/instrumentação , Imagem Óptica/métodos , RNA Viral/análise , Carga Viral/métodos , Animais , Teste de Ácido Nucleico para COVID-19/economia , Teste de Ácido Nucleico para COVID-19/instrumentação , Sistemas CRISPR-Cas , Linhagem Celular , Proteínas do Nucleocapsídeo de Coronavírus/genética , Humanos , Nasofaringe/virologia , Imagem Óptica/instrumentação , Fosfoproteínas/genética , Testes Imediatos , Interferência de RNA , RNA Viral/genética , Sensibilidade e Especificidade , Carga Viral/economia , Carga Viral/instrumentação
5.
Nature ; 610(7930): 128-134, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36171291

RESUMO

To increase computational flexibility, the processing of sensory inputs changes with behavioural context. In the visual system, active behavioural states characterized by motor activity and pupil dilation1,2 enhance sensory responses, but typically leave the preferred stimuli of neurons unchanged2-9. Here we find that behavioural state also modulates stimulus selectivity in the mouse visual cortex in the context of coloured natural scenes. Using population imaging in behaving mice, pharmacology and deep neural network modelling, we identified a rapid shift in colour selectivity towards ultraviolet stimuli during an active behavioural state. This was exclusively caused by state-dependent pupil dilation, which resulted in a dynamic switch from rod to cone photoreceptors, thereby extending their role beyond night and day vision. The change in tuning facilitated the decoding of ethological stimuli, such as aerial predators against the twilight sky10. For decades, studies in neuroscience and cognitive science have used pupil dilation as an indirect measure of brain state. Our data suggest that, in addition, state-dependent pupil dilation itself tunes visual representations to behavioural demands by differentially recruiting rods and cones on fast timescales.


Assuntos
Cor , Pupila , Reflexo Pupilar , Visão Ocular , Córtex Visual , Animais , Escuridão , Aprendizado Profundo , Camundongos , Estimulação Luminosa , Pupila/fisiologia , Pupila/efeitos da radiação , Reflexo Pupilar/fisiologia , Células Fotorreceptoras Retinianas Cones/efeitos dos fármacos , Células Fotorreceptoras Retinianas Cones/fisiologia , Células Fotorreceptoras Retinianas Bastonetes/efeitos dos fármacos , Células Fotorreceptoras Retinianas Bastonetes/fisiologia , Fatores de Tempo , Raios Ultravioleta , Visão Ocular/fisiologia , Córtex Visual/fisiologia
6.
Nature ; 598(7879): 144-150, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33184512

RESUMO

Cortical neurons exhibit extreme diversity in gene expression as well as in morphological and electrophysiological properties1,2. Most existing neural taxonomies are based on either transcriptomic3,4 or morpho-electric5,6 criteria, as it has been technically challenging to study both aspects of neuronal diversity in the same set of cells7. Here we used Patch-seq8 to combine patch-clamp recording, biocytin staining, and single-cell RNA sequencing of more than 1,300 neurons in adult mouse primary motor cortex, providing a morpho-electric annotation of almost all transcriptomically defined neural cell types. We found that, although broad families of transcriptomic types (those expressing Vip, Pvalb, Sst and so on) had distinct and essentially non-overlapping morpho-electric phenotypes, individual transcriptomic types within the same family were not well separated in the morpho-electric space. Instead, there was a continuum of variability in morphology and electrophysiology, with neighbouring transcriptomic cell types showing similar morpho-electric features, often without clear boundaries between them. Our results suggest that neuronal types in the neocortex do not always form discrete entities. Instead, neurons form a hierarchy that consists of distinct non-overlapping branches at the level of families, but can form continuous and correlated transcriptomic and morpho-electrical landscapes within families.


Assuntos
Perfilação da Expressão Gênica , Córtex Motor/citologia , Neurônios/classificação , Neurônios/metabolismo , Transcriptoma , Animais , Atlas como Assunto , Feminino , Neurônios GABAérgicos/citologia , Neurônios GABAérgicos/metabolismo , Glutamatos/metabolismo , Lisina/análogos & derivados , Lisina/análise , Masculino , Camundongos , Córtex Motor/anatomia & histologia , Neurônios/citologia , Especificidade de Órgãos , Técnicas de Patch-Clamp , Fenótipo , Análise de Sequência de RNA , Análise de Célula Única , Coloração e Rotulagem
7.
Nat Methods ; 20(3): 400-402, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36759590

RESUMO

The design of biocatalytic reaction systems is highly complex owing to the dependency of the estimated kinetic parameters on the enzyme, the reaction conditions, and the modeling method. Consequently, reproducibility of enzymatic experiments and reusability of enzymatic data are challenging. We developed the XML-based markup language EnzymeML to enable storage and exchange of enzymatic data such as reaction conditions, the time course of the substrate and the product, kinetic parameters and the kinetic model, thus making enzymatic data findable, accessible, interoperable and reusable (FAIR). The feasibility and usefulness of the EnzymeML toolbox is demonstrated in six scenarios, for which data and metadata of different enzymatic reactions are collected and analyzed. EnzymeML serves as a seamless communication channel between experimental platforms, electronic lab notebooks, tools for modeling of enzyme kinetics, publication platforms and enzymatic reaction databases. EnzymeML is open and transparent, and invites the community to contribute. All documents and codes are freely available at https://enzymeml.org .


Assuntos
Gerenciamento de Dados , Metadados , Reprodutibilidade dos Testes , Bases de Dados Factuais , Cinética
8.
Nat Methods ; 20(7): 1070-1081, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37291262

RESUMO

The development of transgenic mouse models that express genes of interest in specific cell types has transformed our understanding of basic biology and disease. However, generating these models is time- and resource-intensive. Here we describe a model system, SELective Expression and Controlled Transduction In Vivo (SELECTIV), that enables efficient and specific expression of transgenes by coupling adeno-associated virus (AAV) vectors with Cre-inducible overexpression of the multi-serotype AAV receptor, AAVR. We demonstrate that transgenic AAVR overexpression greatly increases the efficiency of transduction of many diverse cell types, including muscle stem cells, which are normally refractory to AAV transduction. Superior specificity is achieved by combining Cre-mediated AAVR overexpression with whole-body knockout of endogenous Aavr, which is demonstrated in heart cardiomyocytes, liver hepatocytes and cholinergic neurons. The enhanced efficacy and exquisite specificity of SELECTIV has broad utility in development of new mouse model systems and expands the use of AAV for gene delivery in vivo.


Assuntos
Técnicas de Transferência de Genes , Vetores Genéticos , Camundongos , Animais , Vetores Genéticos/genética , Camundongos Transgênicos , Terapia Genética , Transgenes , Dependovirus/genética , Transdução Genética
9.
Plant J ; 119(1): 153-175, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38593295

RESUMO

Plant acclimation to an ever-changing environment is decisive for growth, reproduction, and survival. Light availability limits biomass production on both ends of the intensity spectrum. Therefore, the adjustment of plant metabolism is central to high-light (HL) acclimation, and the accumulation of photoprotective anthocyanins is commonly observed. However, mechanisms and factors regulating the HL acclimation response are less clear. Two Arabidopsis mutants of spliceosome components exhibiting a pronounced anthocyanin overaccumulation in HL were isolated from a forward genetic screen for new factors crucial for plant acclimation. Time-resolved physiological, transcriptome, and metabolome analysis revealed a vital function of the spliceosome components for rapidly adjusting gene expression and metabolism. Deficiency of INCREASED LEVEL OF POLYPLOIDY1 (ILP1), NTC-RELATED PROTEIN1 (NTR1), and PLEIOTROPIC REGULATORY LOCUS1 (PRL1) resulted in a marked overaccumulation of carbohydrates and strongly diminished amino acid biosynthesis in HL. While not generally limited in N-assimilation, ilp1, ntr1, and prl1 showed higher glutamate levels and reduced amino acid biosynthesis in HL. The comprehensive analysis reveals a function of the spliceosome components in the conditional regulation of the carbon:nitrogen balance and the accumulation of anthocyanins during HL acclimation. The importance of gene expression, metabolic regulation, and re-direction of carbon towards anthocyanin biosynthesis for HL acclimation are discussed.


Assuntos
Aclimatação , Proteínas de Arabidopsis , Arabidopsis , Carbono , Regulação da Expressão Gênica de Plantas , Luz , Nitrogênio , Spliceossomos , Arabidopsis/genética , Arabidopsis/fisiologia , Arabidopsis/metabolismo , Arabidopsis/efeitos da radiação , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Spliceossomos/metabolismo , Spliceossomos/genética , Carbono/metabolismo , Nitrogênio/metabolismo , Antocianinas/metabolismo
10.
Immunity ; 45(5): 1148-1161, 2016 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-27851915

RESUMO

The impact of epigenetics on the differentiation of memory T (Tmem) cells is poorly defined. We generated deep epigenomes comprising genome-wide profiles of DNA methylation, histone modifications, DNA accessibility, and coding and non-coding RNA expression in naive, central-, effector-, and terminally differentiated CD45RA+ CD4+ Tmem cells from blood and CD69+ Tmem cells from bone marrow (BM-Tmem). We observed a progressive and proliferation-associated global loss of DNA methylation in heterochromatic parts of the genome during Tmem cell differentiation. Furthermore, distinct gradually changing signatures in the epigenome and the transcriptome supported a linear model of memory development in circulating T cells, while tissue-resident BM-Tmem branched off with a unique epigenetic profile. Integrative analyses identified candidate master regulators of Tmem cell differentiation, including the transcription factor FOXP1. This study highlights the importance of epigenomic changes for Tmem cell biology and demonstrates the value of epigenetic data for the identification of lineage regulators.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Diferenciação Celular/imunologia , Epigênese Genética/imunologia , Epigenômica/métodos , Memória Imunológica/imunologia , Feminino , Citometria de Fluxo , Perfilação da Expressão Gênica/métodos , Humanos , Aprendizado de Máquina , Reação em Cadeia da Polimerase , Transcriptoma
11.
PLoS Comput Biol ; 20(5): e1012056, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38781156

RESUMO

Responses to natural stimuli in area V4-a mid-level area of the visual ventral stream-are well predicted by features from convolutional neural networks (CNNs) trained on image classification. This result has been taken as evidence for the functional role of V4 in object classification. However, we currently do not know if and to what extent V4 plays a role in solving other computational objectives. Here, we investigated normative accounts of V4 (and V1 for comparison) by predicting macaque single-neuron responses to natural images from the representations extracted by 23 CNNs trained on different computer vision tasks including semantic, geometric, 2D, and 3D types of tasks. We found that V4 was best predicted by semantic classification features and exhibited high task selectivity, while the choice of task was less consequential to V1 performance. Consistent with traditional characterizations of V4 function that show its high-dimensional tuning to various 2D and 3D stimulus directions, we found that diverse non-semantic tasks explained aspects of V4 function that are not captured by individual semantic tasks. Nevertheless, jointly considering the features of a pair of semantic classification tasks was sufficient to yield one of our top V4 models, solidifying V4's main functional role in semantic processing and suggesting that V4's selectivity to 2D or 3D stimulus properties found by electrophysiologists can result from semantic functional goals.


Assuntos
Modelos Neurológicos , Redes Neurais de Computação , Semântica , Córtex Visual , Animais , Córtex Visual/fisiologia , Biologia Computacional , Estimulação Luminosa , Neurônios/fisiologia , Macaca mulatta , Macaca
12.
Eur Heart J ; 45(3): 214-229, 2024 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-38088437

RESUMO

BACKGROUND AND AIMS: Residual leaks are not infrequent after left atrial appendage occlusion. However, there is still uncertainty regarding their prognostic implications. The aim of this study is to evaluate the impact of residual leaks after left atrial appendage occlusion. METHODS: A literature search was conducted until 19 February 2023. Residual leaks comprised peri-device leaks (PDLs) on transoesophageal echocardiography (TEE) or computed tomography (CT), as well as left atrial appendage patency on CT. Random-effects meta-analyses were performed to assess the clinical impact of residual leaks. RESULTS: Overall 48 eligible studies (44 non-randomized/observational and 4 randomized studies) including 61 666 patients with atrial fibrillation who underwent left atrial appendage occlusion were analysed. Peri-device leak by TEE was present in 26.1% of patients. Computed tomography-based left atrial appendage patency and PDL were present in 54.9% and 57.3% of patients, respectively. Transoesophageal echocardiography-based PDL (i.e. any reported PDL regardless of its size) was significantly associated with a higher risk of thromboembolism [pooled odds ratio (pOR) 2.04, 95% confidence interval (CI): 1.52-2.74], all-cause mortality (pOR 1.16, 95% CI: 1.08-1.24), and major bleeding (pOR 1.12, 95% CI: 1.03-1.22), compared with no reported PDL. A positive graded association between PDL size and risk of thromboembolism was noted across TEE cut-offs. For any PDL of >0, >1, >3, and >5 mm, the pORs for thromboembolism were 1.82 (95% CI: 1.35-2.47), 2.13 (95% CI: 1.04-4.35), 4.14 (95% CI: 2.07-8.27), and 4.44 (95% CI: 2.09-9.43), respectively, compared with either no PDL or PDL smaller than each cut-off. Neither left atrial appendage patency, nor PDL by CT was associated with thromboembolism (pOR 1.45 and 1.04, 95% CI: 0.84-2.50 and 0.52-2.07, respectively). CONCLUSIONS: Peri-device leak detected by TEE was associated with adverse events, primarily thromboembolism. Residual leaks detected by CT were more frequent but lacked prognostic significance.


Assuntos
Apêndice Atrial , Fibrilação Atrial , Tromboembolia , Humanos , Apêndice Atrial/diagnóstico por imagem , Apêndice Atrial/cirurgia , Resultado do Tratamento , Cateterismo Cardíaco/métodos , Tromboembolia/complicações , Ecocardiografia Transesofagiana/efeitos adversos , Fibrilação Atrial/complicações , Fibrilação Atrial/cirurgia
13.
J Neurosci ; 43(44): 7393-7428, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37734947

RESUMO

Larvae of the fruit fly Drosophila melanogaster are a powerful study case for understanding the neural circuits underlying behavior. Indeed, the numerical simplicity of the larval brain has permitted the reconstruction of its synaptic connectome, and genetic tools for manipulating single, identified neurons allow neural circuit function to be investigated with relative ease and precision. We focus on one of the most complex neurons in the brain of the larva (of either sex), the GABAergic anterior paired lateral neuron (APL). Using behavioral and connectomic analyses, optogenetics, Ca2+ imaging, and pharmacology, we study how APL affects associative olfactory memory. We first provide a detailed account of the structure, regional polarity, connectivity, and metamorphic development of APL, and further confirm that optogenetic activation of APL has an inhibiting effect on its main targets, the mushroom body Kenyon cells. All these findings are consistent with the previously identified function of APL in the sparsening of sensory representations. To our surprise, however, we found that optogenetically activating APL can also have a strong rewarding effect. Specifically, APL activation together with odor presentation establishes an odor-specific, appetitive, associative short-term memory, whereas naive olfactory behavior remains unaffected. An acute, systemic inhibition of dopamine synthesis as well as an ablation of the dopaminergic pPAM neurons impair reward learning through APL activation. Our findings provide a study case of complex circuit function in a numerically simple brain, and suggest a previously unrecognized capacity of central-brain GABAergic neurons to engage in dopaminergic reinforcement.SIGNIFICANCE STATEMENT The single, identified giant anterior paired lateral (APL) neuron is one of the most complex neurons in the insect brain. It is GABAergic and contributes to the sparsening of neuronal activity in the mushroom body, the memory center of insects. We provide the most detailed account yet of the structure of APL in larval Drosophila as a neurogenetically accessible study case. We further reveal that, contrary to expectations, the experimental activation of APL can exert a rewarding effect, likely via dopaminergic reward pathways. The present study both provides an example of unexpected circuit complexity in a numerically simple brain, and reports an unexpected effect of activity in central-brain GABAergic circuits.


Assuntos
Drosophila melanogaster , Drosophila , Animais , Drosophila/fisiologia , Larva/fisiologia , Encéfalo/fisiologia , Olfato/fisiologia , Neurônios GABAérgicos/fisiologia , Interneurônios , Dopamina , Recompensa , Corpos Pedunculados/fisiologia
14.
J Virol ; 97(4): e0194822, 2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-36971544

RESUMO

Adeno-associated virus (AAV) vectors are one of the leading platforms for gene delivery for the treatment of human genetic diseases, but the antiviral cellular mechanisms that interfere with optimal transgene expression are incompletely understood. Here, we performed two genome-scale CRISPR screens to identify cellular factors that restrict transgene expression from recombinant AAV vectors. Our screens revealed several components linked to DNA damage response, chromatin remodeling, and transcriptional regulation. Inactivation of the Fanconi anemia gene FANCA; the human silencing hub (HUSH)-associated methyltransferase SETDB1; and the gyrase, Hsp90, histidine kinase, and MutL (GHKL)-type ATPase MORC3 led to increased transgene expression. Moreover, SETDB1 and MORC3 knockout improved transgene levels of several AAV serotypes as well as other viral vectors, such as lentivirus and adenovirus. Finally, we demonstrated that the inhibition of FANCA, SETDB1, or MORC3 also enhanced transgene expression in human primary cells, suggesting that they could be physiologically relevant pathways that restrict AAV transgene levels in therapeutic settings. IMPORTANCE Recombinant AAV (rAAV) vectors have been successfully developed for the treatment of genetic diseases. The therapeutic strategy often involves the replacement of a defective gene by the expression of a functional copy from the rAAV vector genome. However, cells possess antiviral mechanisms that recognize and silence foreign DNA elements thereby limiting transgene expression and its therapeutic effect. Here, we utilize a functional genomics approach to uncover a comprehensive set of cellular restriction factors that inhibit rAAV-based transgene expression. Genetic inactivation of selected restriction factors increased rAAV transgene expression. Hence, modulation of identified restriction factors has the potential to enhance AAV gene replacement therapies.


Assuntos
Fatores de Restrição Antivirais , Dependovirus , Vetores Genéticos , Vetores Genéticos/genética , Vetores Genéticos/imunologia , Dependovirus/genética , Dependovirus/imunologia , Fatores de Restrição Antivirais/genética , Fatores de Restrição Antivirais/metabolismo , Transgenes/genética , Regulação Viral da Expressão Gênica/genética , Células A549 , Células K562 , Técnicas de Inativação de Genes , Células Cultivadas , Humanos , Anemia de Fanconi/genética
15.
Heart Fail Rev ; 29(1): 13-26, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37639067

RESUMO

The echocardiographic tricuspid annular plane systolic excursion/pulmonary artery systolic pressure (TAPSE/PASP) ratio is a non-invasive surrogate of right ventricular-pulmonary arterial (RV-PA) coupling which corresponds well with the respective invasively derived index. Recently, a wealth of observational data has arisen, outlining its prognostic value in heart failure (HF) patients. To systematically appraise and quantitatively synthesize the evidence of the prognostic value of TAPSE/PASP ratio in left-sided HF regardless of etiology or left ventricular ejection fraction. A systematic literature review was conducted in electronic databases to identify studies reporting the association of TAPSE/PASP ratio with outcomes in patients with HF and, when appropriate, a random-effects meta-analysis was conducted to quantify the unadjusted and adjusted hazard ratios [(a)HRs] for all-cause death and the composite outcome of all-cause death or HF hospitalization. Eighteen studies were deemed eligible encompassing 8,699 HF patients. The applied cut-off value for RV-PA uncoupling varied substantially from 0.27 to 0.58 mm/mmHg, and in most studies values lower than the applied cutoff conveyed dismal prognosis. Eleven studies reported appropriate data for meta-analysis. TAPSE/PASP reduction by 1 mm/mmHg was independently associated with all-cause death (pooled aHR=1.32 [1.06-1.65]; p=0.01; I2=56%) and the composite outcome (pooled aHR=3.48 [1.67-7.25]; p<0.001; I2=0%). When a TAPSE/PASP cutoff value of 0.36 mm/mmHg was applied it yielded independent association with all-cause death (pooled aHR=2.84 [2.22-3.64]; p<0.001; I2=82%). RV-PA coupling assessed by echocardiographic TAPSE/PASP ratio appears to be an independent outcome predictor for HF patients.


Assuntos
Insuficiência Cardíaca , Hipertensão Pulmonar , Disfunção Ventricular Direita , Humanos , Ecocardiografia Doppler , Prognóstico , Estudos Prospectivos , Artéria Pulmonar/diagnóstico por imagem , Volume Sistólico , Função Ventricular Esquerda , Função Ventricular Direita
16.
PLoS Comput Biol ; 19(3): e1010932, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36972288

RESUMO

Machine learning models have difficulty generalizing to data outside of the distribution they were trained on. In particular, vision models are usually vulnerable to adversarial attacks or common corruptions, to which the human visual system is robust. Recent studies have found that regularizing machine learning models to favor brain-like representations can improve model robustness, but it is unclear why. We hypothesize that the increased model robustness is partly due to the low spatial frequency preference inherited from the neural representation. We tested this simple hypothesis with several frequency-oriented analyses, including the design and use of hybrid images to probe model frequency sensitivity directly. We also examined many other publicly available robust models that were trained on adversarial images or with data augmentation, and found that all these robust models showed a greater preference to low spatial frequency information. We show that preprocessing by blurring can serve as a defense mechanism against both adversarial attacks and common corruptions, further confirming our hypothesis and demonstrating the utility of low spatial frequency information in robust object recognition.


Assuntos
Aprendizado Profundo , Redes Neurais de Computação , Humanos , Percepção Visual , Aprendizado de Máquina , Cabeça
17.
Heart Vessels ; 39(2): 185-193, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38087071

RESUMO

Atrial fibrillation (AF) is often accompanied by thyroid disease (THD). This study aimed to explore the relationship between THD and the occurrence of significant clinical outcomes in patients with AF. This post hoc analysis utilized data from the MISOAC-AF trial (NCT02941978), which enrolled hospitalized patients with AF. Patients were categorized based on their THD history into hyperthyroidism, hypothyroidism, or euthyroidism. Cox regression models were employed to calculate unadjusted and adjusted hazard ratios (aHRs). The primary outcomes of interest included all-cause mortality, cardiovascular death, and hospitalizations during the follow-up period. The study included 496 AF patients (mean age 73.09 ± 11.10 years) with available THD data, who were followed-up for a median duration of 31 months. Among them, 16 patients (3.2%) had hyperthyroidism, 141 (28.4%) had hypothyroidism, and 339 (68.4%) had no thyroid disease. Patients with hypothyroidism exhibited higher rates of hospitalization during follow-up (aHR: 1.57, 95% CI 1.12 to 2.20, p = 0.025) compared to the euthyroid group. Elevated levels of thyroid-stimulating hormone (TSH) were correlated with an increased risk of cardiovascular mortality (aHR: 1.03, 95% CI 1.01 to 1.05, p = 0.007) and hospitalizations (aHR: 1.06, 95% CI 1.01 to 1.12, p = 0.03). Conversely, lower levels of triiodothyronine (T3) were associated with higher risks of all-cause mortality (aHR: 0.51, 95% CI 0.31 to 0.82, p = 0.006) and cardiovascular mortality (aHR: 0.42, 95% CI 0.23 to 0.77, p = 0.005). Among patients with AF, hypothyroidism was associated with increased hospitalizations. Furthermore, elevated TSH levels and decreased T3 levels were linked to higher cardiovascular and all-cause mortality risks, respectively.


Assuntos
Fibrilação Atrial , Hipertireoidismo , Hipotireoidismo , Doenças da Glândula Tireoide , Idoso , Idoso de 80 Anos ou mais , Humanos , Pessoa de Meia-Idade , Fibrilação Atrial/complicações , Hipertireoidismo/complicações , Hipertireoidismo/diagnóstico , Hipertireoidismo/epidemiologia , Hipotireoidismo/diagnóstico , Hipotireoidismo/epidemiologia , Prognóstico , Fatores de Risco , Doenças da Glândula Tireoide/complicações , Doenças da Glândula Tireoide/diagnóstico , Doenças da Glândula Tireoide/epidemiologia , Tireotropina , Ensaios Clínicos como Assunto
18.
Scand J Med Sci Sports ; 34(4): e14626, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38610121

RESUMO

INTRODUCTION: The potential consequences of repeated concussions in sport are well documented. However, it remains unclear whether the cumulative impact of sports-related concussions differs between different contact sports. Therefore, the aim of the current study was to investigate the cumulative effects of sports-related concussions on clinical and neurocognitive health in different contact sports. MATERIALS AND METHODS: In a prospective multicenter study, we examined 507 (74 females) active professional athletes between 18 and 40 years of age from five different contact sports (soccer, handball, American football, basketball, and ice hockey). Data collection involved concussion history, clinical symptom evaluation, neurocognitive assessment, and the collection of other sports-related information. Composite scores were built for clinical symptoms (such as neck pain and balance disturbances) and for neurocognitive symptoms (such as memory and attention impairments). RESULTS: Athletes having suffered 3+ concussions in the past showed disproportionally higher clinical symptom severity than athletes with less than three concussions across all sports. The level of clinical symptom burden in athletes with 3+ concussions indicated mild impairment. The number of past concussions did not affect neurocognitive performance. DISCUSSION: Repeated sports-related concussions appear to have a cumulative impact on clinical-but not cognitive-symptom severity. Although clinical symptom burden in athletes with 3+ concussions in the past was not alarmingly high yet in our sample, increased caution should be advised at this point. Despite few exceptions, results are similar for different contact sports, suggesting a similar multidisciplinary concussion management across all types of sport.


Assuntos
Basquetebol , Concussão Encefálica , Futebol , Feminino , Humanos , Estudos Prospectivos , Atletas , Concussão Encefálica/complicações
19.
Aust N Z J Psychiatry ; 58(4): 308-319, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38179705

RESUMO

OBJECTIVES: Binge spectrum disorders are prevalent worldwide. Psychiatric and medical comorbidities are common, and societal costs are significant. Evidence-based treatment remains underutilized. Cognitive behavioral therapy is the recommended first-line treatment, but pharmacotherapy may be easier to access. INTERVENTIONS: Meta-analytic evidence directly comparing cognitive behavioral therapy with pharmacotherapy is lacking. We aimed to compare the effects of cognitive behavioral therapy interventions with any pharmacological treatment for binge spectrum disorders. We searched PubMed, Embase, CENTRAL, ClinicalTrials.gov and reference lists for randomized controlled trials comparing cognitive behavioral therapy with any pharmacotherapy for bulimia nervosa/binge eating disorder and performed pairwise meta-analytic evaluations. PRIMARY OUTCOMES: Primary outcomes are remission and frequency of binges. Secondary outcomes are frequency of purges, response, eating disorder psychopathology, weight/body mass index, depression, anxiety, quality of life and dropouts. RESULTS: Eleven randomized controlled trials comparing cognitive behavioral therapy with fluoxetine/imipramine/desipramine/methylphenidate/sibutramine were identified (N = 531). Cognitive behavioral therapy was superior to antidepressants in terms of remission, frequency of binges and eating disorder psychopathology. There were no statistically significant differences for any of the individual cognitive behavioral therapy vs drug comparisons in terms of response/depression/anxiety/weight/quality of life/dropouts. Cognitive behavioral therapy was not superior to sibutramine/methylphenidate for the primary outcomes. CONCLUSIONS: Data are scarce, comparisons underpowered and, considering the inherent methodological limitations of psychotherapy trials, questions arise regarding the presumed superiority of cognitive behavioral therapy. Further research is needed.


Assuntos
Terapia Cognitivo-Comportamental , Ciclobutanos , Metilfenidato , Humanos , Qualidade de Vida , Psicoterapia , Resultado do Tratamento
20.
PLoS Genet ; 17(4): e1009495, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33914747

RESUMO

Parallel changes in genotype and phenotype in response to similar selection pressures in different populations provide compelling evidence of adaptation. House mice (Mus musculus domesticus) have recently colonized North America and are found in a wide range of environments. Here we measure phenotypic and genotypic differentiation among house mice from five populations sampled across 21° of latitude in western North America, and we compare our results to a parallel latitudinal cline in eastern North America. First, we show that mice are genetically differentiated between transects, indicating that they have independently colonized similar environments in eastern and western North America. Next, we find genetically-based differences in body weight and nest building behavior between mice from the ends of the western transect which mirror differences seen in the eastern transect, demonstrating parallel phenotypic change. We then conduct genome-wide scans for selection and a genome-wide association study to identify targets of selection and candidate genes for body weight. We find some genomic signatures that are unique to each transect, indicating population-specific responses to selection. However, there is significant overlap between genes under selection in eastern and western house mouse transects, providing evidence of parallel genetic evolution in response to similar selection pressures across North America.


Assuntos
Aclimatação/genética , Adaptação Fisiológica/genética , Evolução Molecular , Seleção Genética/genética , Animais , Peso Corporal/genética , Variação Genética/genética , Estudo de Associação Genômica Ampla/métodos , Genômica , Camundongos , América do Norte , Fenótipo
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