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1.
Annu Rev Neurosci ; 47(1): 323-344, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38648267

RESUMO

Since its recent discovery, the meningeal lymphatic system has reshaped our understanding of central nervous system (CNS) fluid exchange, waste clearance, immune cell trafficking, and immune privilege. Meningeal lymphatics have also been demonstrated to functionally modify the outcome of neurological disorders and their responses to treatment, including brain tumors, inflammatory diseases such as multiple sclerosis, CNS injuries, and neurodegenerative disorders such as Alzheimer's and Parkinson's diseases. In this review, we discuss recent evidence of the contribution of meningeal lymphatics to neurological diseases, as well as the available experimental methods for manipulating meningeal lymphatics in these conditions. Finally, we also provide a discussion of the pressing questions and challenges in utilizing meningeal lymphatics as a prime target for CNS therapeutic intervention and possibly drug delivery for brain disorders.


Assuntos
Doenças do Sistema Nervoso Central , Meninges , Humanos , Animais , Doenças do Sistema Nervoso Central/fisiopatologia , Doenças do Sistema Nervoso Central/patologia , Sistema Linfático/fisiologia , Sistema Linfático/fisiopatologia , Vasos Linfáticos/fisiologia
2.
Annu Rev Neurosci ; 47(1): 85-101, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38424472

RESUMO

Predictive processing is a computational framework that aims to explain how the brain processes sensory information by making predictions about the environment and minimizing prediction errors. It can also be used to explain some of the key symptoms of psychotic disorders such as schizophrenia. In recent years, substantial advances have been made in our understanding of the neuronal circuitry that underlies predictive processing in cortex. In this review, we summarize these findings and how they might relate to psychosis and to observed cell type-specific effects of antipsychotic drugs. We argue that quantifying the effects of antipsychotic drugs on specific neuronal circuit elements is a promising approach to understanding not only the mechanism of action of antipsychotic drugs but also psychosis. Finally, we outline some of the key experiments that should be done. The aims of this review are to provide an overview of the current circuit-based approaches to psychosis and to encourage further research in this direction.


Assuntos
Transtornos Psicóticos , Humanos , Transtornos Psicóticos/fisiopatologia , Animais , Antipsicóticos/uso terapêutico , Antipsicóticos/farmacologia , Encéfalo/fisiopatologia , Encéfalo/fisiologia , Rede Nervosa/fisiopatologia , Rede Nervosa/fisiologia , Esquizofrenia/fisiopatologia , Vias Neurais/fisiopatologia , Vias Neurais/fisiologia , Modelos Neurológicos
3.
Annu Rev Neurosci ; 47(1): 63-83, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38424473

RESUMO

Deep brain stimulation (DBS), a method in which electrical stimulation is delivered to specific areas of the brain, is an effective treatment for managing symptoms of a number of neurological and neuropsychiatric disorders. Clinical access to neural circuits during DBS provides an opportunity to study the functional link between neural circuits and behavior. This review discusses how the use of DBS in Parkinson's disease and dystonia has provided insights into the brain networks and physiological mechanisms that underlie motor control. In parallel, insights from basic science about how patterns of electrical stimulation impact plasticity and communication within neural circuits are transforming DBS from a therapy for treating symptoms to a therapy for treating circuits, with the goal of training the brain out of its diseased state.


Assuntos
Encéfalo , Estimulação Encefálica Profunda , Doença de Parkinson , Estimulação Encefálica Profunda/métodos , Humanos , Doença de Parkinson/terapia , Doença de Parkinson/fisiopatologia , Animais , Encéfalo/fisiologia , Encéfalo/fisiopatologia , Movimento/fisiologia , Distonia/terapia , Distonia/fisiopatologia , Rede Nervosa/fisiologia , Vias Neurais/fisiologia , Plasticidade Neuronal/fisiologia
4.
Annu Rev Neurosci ; 47(1): 103-121, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38594945

RESUMO

The cochlear implant (CI) is considered the most successful neuroprosthesis as it enables speech comprehension in the majority of the million otherwise deaf patients. In hearing by electrical stimulation of the auditory nerve, the broad spread of current from each electrode acts as a bottleneck that limits the transfer of sound frequency information. Hence, there remains a major unmet medical need for improving the quality of hearing with CIs. Recently, optogenetic stimulation of the cochlea has been suggested as an alternative approach for hearing restoration. Cochlear optogenetics promises to transfer more sound frequency information, hence improving hearing, as light can conveniently be confined in space to activate the auditory nerve within smaller tonotopic ranges. In this review, we discuss the latest experimental and technological developments of optogenetic hearing restoration and outline remaining challenges en route to clinical translation.


Assuntos
Implantes Cocleares , Optogenética , Optogenética/métodos , Humanos , Animais , Perda Auditiva/fisiopatologia , Audição/fisiologia , Cóclea/fisiologia
5.
Genes Dev ; 38(9-10): 360-379, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38811170

RESUMO

Glioblastoma (GBM) is the most aggressive primary brain cancer. These tumors exhibit high intertumoral and intratumoral heterogeneity in neoplastic and nonneoplastic compartments, low lymphocyte infiltration, and high abundance of myeloid subsets that together create a highly protumorigenic immunosuppressive microenvironment. Moreover, heterogeneous GBM cells infiltrate adjacent brain tissue, remodeling the neural microenvironment to foster tumor electrochemical coupling with neurons and metabolic coupling with nonneoplastic astrocytes, thereby driving growth. Here, we review heterogeneity in the GBM microenvironment and its role in low-to-high-grade glioma transition, concluding with a discussion of the challenges of therapeutically targeting the tumor microenvironment and outlining future research opportunities.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Microambiente Tumoral , Humanos , Glioblastoma/terapia , Glioblastoma/fisiopatologia , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/fisiopatologia , Neoplasias Encefálicas/patologia , Animais
6.
Physiol Rev ; 104(3): 1205-1263, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38483288

RESUMO

Stress resilience is the phenomenon that some people maintain their mental health despite exposure to adversity or show only temporary impairments followed by quick recovery. Resilience research attempts to unravel the factors and mechanisms that make resilience possible and to harness its insights for the development of preventative interventions in individuals at risk for acquiring stress-related dysfunctions. Biological resilience research has been lagging behind the psychological and social sciences but has seen a massive surge in recent years. At the same time, progress in this field has been hampered by methodological challenges related to finding suitable operationalizations and study designs, replicating findings, and modeling resilience in animals. We embed a review of behavioral, neuroimaging, neurobiological, and systems biological findings in adults in a critical methods discussion. We find preliminary evidence that hippocampus-based pattern separation and prefrontal-based cognitive control functions protect against the development of pathological fears in the aftermath of singular, event-type stressors [as found in fear-related disorders, including simpler forms of posttraumatic stress disorder (PTSD)] by facilitating the perception of safety. Reward system-based pursuit and savoring of positive reinforcers appear to protect against the development of more generalized dysfunctions of the anxious-depressive spectrum resulting from more severe or longer-lasting stressors (as in depression, generalized or comorbid anxiety, or severe PTSD). Links between preserved functioning of these neural systems under stress and neuroplasticity, immunoregulation, gut microbiome composition, and integrity of the gut barrier and the blood-brain barrier are beginning to emerge. On this basis, avenues for biological interventions are pointed out.


Assuntos
Neurobiologia , Resiliência Psicológica , Estresse Psicológico , Biologia de Sistemas , Humanos , Animais , Estresse Psicológico/fisiopatologia , Encéfalo
7.
Physiol Rev ; 104(3): 1265-1333, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38153307

RESUMO

The complexity of cardiac electrophysiology, involving dynamic changes in numerous components across multiple spatial (from ion channel to organ) and temporal (from milliseconds to days) scales, makes an intuitive or empirical analysis of cardiac arrhythmogenesis challenging. Multiscale mechanistic computational models of cardiac electrophysiology provide precise control over individual parameters, and their reproducibility enables a thorough assessment of arrhythmia mechanisms. This review provides a comprehensive analysis of models of cardiac electrophysiology and arrhythmias, from the single cell to the organ level, and how they can be leveraged to better understand rhythm disorders in cardiac disease and to improve heart patient care. Key issues related to model development based on experimental data are discussed, and major families of human cardiomyocyte models and their applications are highlighted. An overview of organ-level computational modeling of cardiac electrophysiology and its clinical applications in personalized arrhythmia risk assessment and patient-specific therapy of atrial and ventricular arrhythmias is provided. The advancements presented here highlight how patient-specific computational models of the heart reconstructed from patient data have achieved success in predicting risk of sudden cardiac death and guiding optimal treatments of heart rhythm disorders. Finally, an outlook toward potential future advances, including the combination of mechanistic modeling and machine learning/artificial intelligence, is provided. As the field of cardiology is embarking on a journey toward precision medicine, personalized modeling of the heart is expected to become a key technology to guide pharmaceutical therapy, deployment of devices, and surgical interventions.


Assuntos
Arritmias Cardíacas , Modelos Cardiovasculares , Humanos , Arritmias Cardíacas/fisiopatologia , Animais , Simulação por Computador , Pesquisa Translacional Biomédica , Miócitos Cardíacos/fisiologia , Fenômenos Eletrofisiológicos/fisiologia , Potenciais de Ação/fisiologia
8.
Nature ; 629(8012): 652-659, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38693261

RESUMO

The gut microbiota operates at the interface of host-environment interactions to influence human homoeostasis and metabolic networks1-4. Environmental factors that unbalance gut microbial ecosystems can therefore shape physiological and disease-associated responses across somatic tissues5-9. However, the systemic impact of the gut microbiome on the germline-and consequently on the F1 offspring it gives rise to-is unexplored10. Here we show that the gut microbiota act as a key interface between paternal preconception environment and intergenerational health in mice. Perturbations to the gut microbiota of prospective fathers increase the probability of their offspring presenting with low birth weight, severe growth restriction and premature mortality. Transmission of disease risk occurs via the germline and is provoked by pervasive gut microbiome perturbations, including non-absorbable antibiotics or osmotic laxatives, but is rescued by restoring the paternal microbiota before conception. This effect is linked with a dynamic response to induced dysbiosis in the male reproductive system, including impaired leptin signalling, altered testicular metabolite profiles and remapped small RNA payloads in sperm. As a result, dysbiotic fathers trigger an elevated risk of in utero placental insufficiency, revealing a placental origin of mammalian intergenerational effects. Our study defines a regulatory 'gut-germline axis' in males, which is sensitive to environmental exposures and programmes offspring fitness through impacting placenta function.


Assuntos
Suscetibilidade a Doenças , Disbiose , Pai , Microbioma Gastrointestinal , Insuficiência Placentária , Lesões Pré-Natais , Espermatozoides , Animais , Feminino , Masculino , Camundongos , Gravidez , Disbiose/complicações , Disbiose/microbiologia , Microbioma Gastrointestinal/fisiologia , Leptina/metabolismo , Camundongos Endogâmicos C57BL , Placenta/metabolismo , Placenta/fisiopatologia , Insuficiência Placentária/etiologia , Insuficiência Placentária/metabolismo , Insuficiência Placentária/fisiopatologia , Resultado da Gravidez , Lesões Pré-Natais/etiologia , Lesões Pré-Natais/metabolismo , Lesões Pré-Natais/fisiopatologia , Transdução de Sinais , Espermatozoides/metabolismo , Testículo/metabolismo , Testículo/fisiopatologia , Suscetibilidade a Doenças/etiologia
9.
Nature ; 630(8018): 935-942, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38867049

RESUMO

Memories benefit from sleep1, and the reactivation and replay of waking experiences during hippocampal sharp-wave ripples (SWRs) are considered to be crucial for this process2. However, little is known about how these patterns are impacted by sleep loss. Here we recorded CA1 neuronal activity over 12 h in rats across maze exploration, sleep and sleep deprivation, followed by recovery sleep. We found that SWRs showed sustained or higher rates during sleep deprivation but with lower power and higher frequency ripples. Pyramidal cells exhibited sustained firing during sleep deprivation and reduced firing during sleep, yet their firing rates were comparable during SWRs regardless of sleep state. Despite the robust firing and abundance of SWRs during sleep deprivation, we found that the reactivation and replay of neuronal firing patterns was diminished during these periods and, in some cases, completely abolished compared to ad libitum sleep. Reactivation partially rebounded after recovery sleep but failed to reach the levels found in natural sleep. These results delineate the adverse consequences of sleep loss on hippocampal function at the network level and reveal a dissociation between the many SWRs elicited during sleep deprivation and the few reactivations and replays that occur during these events.


Assuntos
Hipocampo , Privação do Sono , Sono de Ondas Lentas , Animais , Feminino , Masculino , Ratos , Região CA1 Hipocampal/citologia , Região CA1 Hipocampal/fisiologia , Região CA1 Hipocampal/fisiopatologia , Aprendizagem em Labirinto/fisiologia , Memória/fisiologia , Células Piramidais/fisiologia , Ratos Long-Evans , Privação do Sono/fisiopatologia , Sono de Ondas Lentas/fisiologia , Vigília/fisiologia , Fatores de Tempo , Hipocampo/citologia , Hipocampo/fisiologia , Hipocampo/fisiopatologia
10.
Nature ; 627(8005): 839-846, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38509363

RESUMO

The bone marrow adjusts blood cell production to meet physiological demands in response to insults. The spatial organization of normal and stress responses are unknown owing to the lack of methods to visualize most steps of blood production. Here we develop strategies to image multipotent haematopoiesis, erythropoiesis and lymphopoiesis in mice. We combine these with imaging of myelopoiesis1 to define the anatomy of normal and stress haematopoiesis. In the steady state, across the skeleton, single stem cells and multipotent progenitors distribute through the marrow enriched near megakaryocytes. Lineage-committed progenitors are recruited to blood vessels, where they contribute to lineage-specific microanatomical structures composed of progenitors and immature cells, which function as the production sites for each major blood lineage. This overall anatomy is resilient to insults, as it was maintained after haemorrhage, systemic bacterial infection and granulocyte colony-stimulating factor (G-CSF) treatment, and during ageing. Production sites enable haematopoietic plasticity as they differentially and selectively modulate their numbers and output in response to insults. We found that stress responses are variable across the skeleton: the tibia and the sternum respond in opposite ways to G-CSF, and the skull does not increase erythropoiesis after haemorrhage. Our studies enable in situ analyses of haematopoiesis, define the anatomy of normal and stress responses, identify discrete microanatomical production sites that confer plasticity to haematopoiesis, and uncover unprecedented heterogeneity of stress responses across the skeleton.


Assuntos
Hematopoese , Células-Tronco Hematopoéticas , Estresse Fisiológico , Animais , Feminino , Masculino , Camundongos , Envelhecimento/fisiologia , Infecções Bacterianas/patologia , Infecções Bacterianas/fisiopatologia , Vasos Sanguíneos/citologia , Linhagem da Célula , Eritropoese , Fator Estimulador de Colônias de Granulócitos/metabolismo , Hematopoese/fisiologia , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Hemorragia/patologia , Hemorragia/fisiopatologia , Linfopoese , Megacariócitos/citologia , Células-Tronco Multipotentes/citologia , Células-Tronco Multipotentes/metabolismo , Mielopoese , Crânio/irrigação sanguínea , Crânio/patologia , Crânio/fisiopatologia , Esterno/irrigação sanguínea , Esterno/citologia , Esterno/metabolismo , Estresse Fisiológico/fisiologia , Tíbia/irrigação sanguínea , Tíbia/citologia , Tíbia/metabolismo
11.
Nature ; 631(8021): 601-609, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38987587

RESUMO

Exaggerated airway constriction triggered by repeated exposure to allergen, also called hyperreactivity, is a hallmark of asthma. Whereas vagal sensory neurons are known to function in allergen-induced hyperreactivity1-3, the identity of downstream nodes remains poorly understood. Here we mapped a full allergen circuit from the lung to the brainstem and back to the lung. Repeated exposure of mice to inhaled allergen activated the nuclei of solitary tract (nTS) neurons in a mast cell-, interleukin-4 (IL-4)- and vagal nerve-dependent manner. Single-nucleus RNA sequencing, followed by RNAscope assay at baseline and allergen challenges, showed that a Dbh+ nTS population is preferentially activated. Ablation or chemogenetic inactivation of Dbh+ nTS neurons blunted hyperreactivity whereas chemogenetic activation promoted it. Viral tracing indicated that Dbh+ nTS neurons project to the nucleus ambiguus (NA) and that NA neurons are necessary and sufficient to relay allergen signals to postganglionic neurons that directly drive airway constriction. Delivery of noradrenaline antagonists to the NA blunted hyperreactivity, suggesting noradrenaline as the transmitter between Dbh+ nTS and NA. Together, these findings provide molecular, anatomical and functional definitions of key nodes of a canonical allergen response circuit. This knowledge informs how neural modulation could be used to control allergen-induced airway hyperreactivity.


Assuntos
Alérgenos , Tronco Encefálico , Hiper-Reatividade Brônquica , Dopamina beta-Hidroxilase , Pulmão , Neurônios , Animais , Feminino , Masculino , Camundongos , Alérgenos/imunologia , Asma/imunologia , Asma/fisiopatologia , Tronco Encefálico/citologia , Tronco Encefálico/fisiologia , Hiper-Reatividade Brônquica/tratamento farmacológico , Hiper-Reatividade Brônquica/imunologia , Hiper-Reatividade Brônquica/fisiopatologia , Interleucina-4/imunologia , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Pulmão/inervação , Pulmão/fisiopatologia , Mastócitos/imunologia , Neurônios/enzimologia , Neurônios/fisiologia , Norepinefrina/antagonistas & inibidores , Norepinefrina/metabolismo , Núcleo Solitário/citologia , Núcleo Solitário/fisiologia , Nervo Vago/citologia , Nervo Vago/fisiologia , Bulbo/citologia , Bulbo/efeitos dos fármacos , Gânglios Autônomos/citologia , Dopamina beta-Hidroxilase/metabolismo
12.
Nature ; 632(8023): 55-62, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39085539

RESUMO

Advancements in optical coherence control1-5 have unlocked many cutting-edge applications, including long-haul communication, light detection and ranging (LiDAR) and optical coherence tomography6-8. Prevailing wisdom suggests that using more coherent light sources leads to enhanced system performance and device functionalities9-11. Our study introduces a photonic convolutional processing system that takes advantage of partially coherent light to boost computing parallelism without substantially sacrificing accuracy, potentially enabling larger-size photonic tensor cores. The reduction of the degree of coherence optimizes bandwidth use in the photonic convolutional processing system. This breakthrough challenges the traditional belief that coherence is essential or even advantageous in integrated photonic accelerators, thereby enabling the use of light sources with less rigorous feedback control and thermal-management requirements for high-throughput photonic computing. Here we demonstrate such a system in two photonic platforms for computing applications: a photonic tensor core using phase-change-material photonic memories that delivers parallel convolution operations to classify the gaits of ten patients with Parkinson's disease with 92.2% accuracy (92.7% theoretically) and a silicon photonic tensor core with embedded electro-absorption modulators (EAMs) to facilitate 0.108 tera operations per second (TOPS) convolutional processing for classifying the Modified National Institute of Standards and Technology (MNIST) handwritten digits dataset with 92.4% accuracy (95.0% theoretically).


Assuntos
Redes Neurais de Computação , Óptica e Fotônica , Fótons , Tomografia de Coerência Óptica , Humanos , Óptica e Fotônica/instrumentação , Óptica e Fotônica/métodos , Doença de Parkinson/diagnóstico , Doença de Parkinson/fisiopatologia , Silício/química , Tomografia de Coerência Óptica/instrumentação , Tomografia de Coerência Óptica/métodos , Marcha/fisiologia , Conjuntos de Dados como Assunto , Sensibilidade e Especificidade
13.
Nature ; 629(8011): 402-409, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38632412

RESUMO

Throughout life, neuronal networks in the mammalian neocortex maintain a balance of excitation and inhibition, which is essential for neuronal computation1,2. Deviations from a balanced state have been linked to neurodevelopmental disorders, and severe disruptions result in epilepsy3-5. To maintain balance, neuronal microcircuits composed of excitatory and inhibitory neurons sense alterations in neural activity and adjust neuronal connectivity and function. Here we identify a signalling pathway in the adult mouse neocortex that is activated in response to increased neuronal network activity. Overactivation of excitatory neurons is signalled to the network through an increase in the levels of BMP2, a growth factor that is well known for its role as a morphogen in embryonic development. BMP2 acts on parvalbumin-expressing (PV) interneurons through the transcription factor SMAD1, which controls an array of glutamatergic synapse proteins and components of perineuronal nets. PV-interneuron-specific disruption of BMP2-SMAD1 signalling is accompanied by a loss of glutamatergic innervation in PV cells, underdeveloped perineuronal nets and decreased excitability. Ultimately, this impairment of the functional recruitment of PV interneurons disrupts the cortical excitation-inhibition balance, with mice exhibiting spontaneous epileptic seizures. Our findings suggest that developmental morphogen signalling is repurposed to stabilize cortical networks in the adult mammalian brain.


Assuntos
Proteína Morfogenética Óssea 2 , Interneurônios , Neocórtex , Rede Nervosa , Inibição Neural , Neurônios , Transdução de Sinais , Proteína Smad1 , Animais , Feminino , Humanos , Masculino , Camundongos , Proteína Morfogenética Óssea 2/metabolismo , Epilepsia/metabolismo , Epilepsia/fisiopatologia , Interneurônios/metabolismo , Neocórtex/metabolismo , Neocórtex/citologia , Rede Nervosa/metabolismo , Neurônios/metabolismo , Parvalbuminas/metabolismo , Proteína Smad1/metabolismo , Sinapses/metabolismo , Ácido Glutâmico/metabolismo
14.
Nature ; 627(8003): 347-357, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38374256

RESUMO

Type 2 diabetes (T2D) is a heterogeneous disease that develops through diverse pathophysiological processes1,2 and molecular mechanisms that are often specific to cell type3,4. Here, to characterize the genetic contribution to these processes across ancestry groups, we aggregate genome-wide association study data from 2,535,601 individuals (39.7% not of European ancestry), including 428,452 cases of T2D. We identify 1,289 independent association signals at genome-wide significance (P < 5 × 10-8) that map to 611 loci, of which 145 loci are, to our knowledge, previously unreported. We define eight non-overlapping clusters of T2D signals that are characterized by distinct profiles of cardiometabolic trait associations. These clusters are differentially enriched for cell-type-specific regions of open chromatin, including pancreatic islets, adipocytes, endothelial cells and enteroendocrine cells. We build cluster-specific partitioned polygenic scores5 in a further 279,552 individuals of diverse ancestry, including 30,288 cases of T2D, and test their association with T2D-related vascular outcomes. Cluster-specific partitioned polygenic scores are associated with coronary artery disease, peripheral artery disease and end-stage diabetic nephropathy across ancestry groups, highlighting the importance of obesity-related processes in the development of vascular outcomes. Our findings show the value of integrating multi-ancestry genome-wide association study data with single-cell epigenomics to disentangle the aetiological heterogeneity that drives the development and progression of T2D. This might offer a route to optimize global access to genetically informed diabetes care.


Assuntos
Diabetes Mellitus Tipo 2 , Progressão da Doença , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Adipócitos/metabolismo , Cromatina/genética , Cromatina/metabolismo , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/genética , Diabetes Mellitus Tipo 2/classificação , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/patologia , Diabetes Mellitus Tipo 2/fisiopatologia , Nefropatias Diabéticas/complicações , Nefropatias Diabéticas/genética , Células Endoteliais/metabolismo , Células Enteroendócrinas , Epigenômica , Predisposição Genética para Doença/genética , Ilhotas Pancreáticas/metabolismo , Herança Multifatorial/genética , Doença Arterial Periférica/complicações , Doença Arterial Periférica/genética , Análise de Célula Única
15.
Nature ; 631(8021): 645-653, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38987596

RESUMO

Platelet homeostasis is essential for vascular integrity and immune defence1,2. Although the process of platelet formation by fragmenting megakaryocytes (MKs; thrombopoiesis) has been extensively studied, the cellular and molecular mechanisms required to constantly replenish the pool of MKs by their progenitor cells (megakaryopoiesis) remains unclear3,4. Here we use intravital imaging to track the cellular dynamics of megakaryopoiesis over days. We identify plasmacytoid dendritic cells (pDCs) as homeostatic sensors that monitor the bone marrow for apoptotic MKs and deliver IFNα to the MK niche triggering local on-demand proliferation and maturation of MK progenitors. This pDC-dependent feedback loop is crucial for MK and platelet homeostasis at steady state and under stress. pDCs are best known for their ability to function as vigilant detectors of viral infection5. We show that virus-induced activation of pDCs interferes with their function as homeostatic sensors of megakaryopoiesis. Consequently, activation of pDCs by SARS-CoV-2 leads to excessive megakaryopoiesis. Together, we identify a pDC-dependent homeostatic circuit that involves innate immune sensing and demand-adapted release of inflammatory mediators to maintain homeostasis of the megakaryocytic lineage.


Assuntos
Células Dendríticas , Homeostase , Megacariócitos , Trombopoese , Animais , Feminino , Humanos , Masculino , Camundongos , Apoptose , Plaquetas/citologia , Medula Óssea , Linhagem da Célula , Proliferação de Células , Células Dendríticas/imunologia , Células Dendríticas/citologia , Retroalimentação Fisiológica , Imunidade Inata , Microscopia Intravital , Megacariócitos/citologia , Megacariócitos/imunologia , Camundongos Endogâmicos C57BL , SARS-CoV-2/imunologia , COVID-19/imunologia , COVID-19/fisiopatologia , COVID-19/virologia
16.
Nat Rev Neurosci ; 25(5): 313-333, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38594324

RESUMO

Compulsive behaviour, an apparently irrational perseveration in often maladaptive acts, is a potential transdiagnostic symptom of several neuropsychiatric disorders, including obsessive-compulsive disorder and addiction, and may reflect the severe manifestation of a dimensional trait termed compulsivity. In this Review, we examine the psychological basis of compulsions and compulsivity and their underlying neural circuitry using evidence from human neuroimaging and animal models. Several main elements of this circuitry are identified, focused on fronto-striatal systems implicated in goal-directed behaviour and habits. These systems include the orbitofrontal, prefrontal, anterior cingulate and insular cortices and their connections with the basal ganglia as well as sensoriomotor and parietal cortices and cerebellum. We also consider the implications for future classification of impulsive-compulsive disorders and their treatment.


Assuntos
Comportamento Compulsivo , Humanos , Comportamento Compulsivo/fisiopatologia , Comportamento Compulsivo/psicologia , Animais , Encéfalo/fisiopatologia , Encéfalo/patologia , Transtorno Obsessivo-Compulsivo/fisiopatologia , Transtorno Obsessivo-Compulsivo/psicologia , Vias Neurais/fisiopatologia
17.
Nat Rev Neurosci ; 25(8): 573-586, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38937655

RESUMO

Bradykinesia, or slowness of movement, is a defining feature of Parkinson disease (PD) and a major contributor to the negative effects on quality of life associated with this disorder and related conditions. A dominant pathophysiological model of bradykinesia in PD has existed for approximately 30 years and has been the basis for the development of several therapeutic interventions, but accumulating evidence has made this model increasingly untenable. Although more recent models have been proposed, they also appear to be flawed. In this Perspective, I consider the leading prior models of bradykinesia in PD and argue that a more functionally related model is required, one that considers changes that disrupt the fundamental process of accurate information transmission. In doing so, I review emerging evidence of network level functional connectivity changes, information transfer dysfunction and potential motor code transmission error and present a novel model of bradykinesia in PD that incorporates this evidence. I hope that this model may reconcile inconsistencies in its predecessors and encourage further development of therapeutic interventions.


Assuntos
Hipocinesia , Doença de Parkinson , Humanos , Hipocinesia/fisiopatologia , Doença de Parkinson/fisiopatologia , Doença de Parkinson/complicações , Animais , Modelos Neurológicos , Encéfalo/fisiopatologia
18.
N Engl J Med ; 391(7): 598-608, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39141852

RESUMO

BACKGROUND: Patients with brain injury who are unresponsive to commands may perform cognitive tasks that are detected on functional magnetic resonance imaging (fMRI) and electroencephalography (EEG). This phenomenon, known as cognitive motor dissociation, has not been systematically studied in a large cohort of persons with disorders of consciousness. METHODS: In this prospective cohort study conducted at six international centers, we collected clinical, behavioral, and task-based fMRI and EEG data from a convenience sample of 353 adults with disorders of consciousness. We assessed the response to commands on task-based fMRI or EEG in participants without an observable response to verbal commands (i.e., those with a behavioral diagnosis of coma, vegetative state, or minimally conscious state-minus) and in participants with an observable response to verbal commands. The presence or absence of an observable response to commands was assessed with the use of the Coma Recovery Scale-Revised (CRS-R). RESULTS: Data from fMRI only or EEG only were available for 65% of the participants, and data from both fMRI and EEG were available for 35%. The median age of the participants was 37.9 years, the median time between brain injury and assessment with the CRS-R was 7.9 months (25% of the participants were assessed with the CRS-R within 28 days after injury), and brain trauma was an etiologic factor in 50%. We detected cognitive motor dissociation in 60 of the 241 participants (25%) without an observable response to commands, of whom 11 had been assessed with the use of fMRI only, 13 with the use of EEG only, and 36 with the use of both techniques. Cognitive motor dissociation was associated with younger age, longer time since injury, and brain trauma as an etiologic factor. In contrast, responses on task-based fMRI or EEG occurred in 43 of 112 participants (38%) with an observable response to verbal commands. CONCLUSIONS: Approximately one in four participants without an observable response to commands performed a cognitive task on fMRI or EEG as compared with one in three participants with an observable response to commands. (Funded by the James S. McDonnell Foundation and others.).


Assuntos
Lesões Encefálicas , Transtornos da Consciência , Transtornos Dissociativos , Estado Vegetativo Persistente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Lesões Encefálicas/fisiopatologia , Lesões Encefálicas/complicações , Lesões Encefálicas/diagnóstico por imagem , Cognição/fisiologia , Transtornos da Consciência/diagnóstico por imagem , Transtornos da Consciência/etiologia , Transtornos da Consciência/fisiopatologia , Eletroencefalografia , Imageamento por Ressonância Magnética , Estado Vegetativo Persistente/diagnóstico por imagem , Estado Vegetativo Persistente/etiologia , Estado Vegetativo Persistente/fisiopatologia , Estudos Prospectivos , Transtornos Dissociativos/diagnóstico por imagem , Transtornos Dissociativos/etiologia , Transtornos Dissociativos/fisiopatologia
19.
N Engl J Med ; 390(3): 212-220, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38231622

RESUMO

BACKGROUND: The Resynchronization-Defibrillation for Ambulatory Heart Failure Trial (RAFT) showed a greater benefit with respect to mortality at 5 years among patients who received cardiac-resynchronization therapy (CRT) than among those who received implantable cardioverter-defibrillators (ICDs). However, the effect of CRT on long-term survival is not known. METHODS: We randomly assigned patients with New York Heart Association (NYHA) class II or III heart failure, a left ventricular ejection fraction of 30% or less, and an intrinsic QRS duration of 120 msec or more (or a paced QRS duration of 200 msec or more) to receive either an ICD alone or a CRT defibrillator (CRT-D). We assessed long-term outcomes among patients at the eight highest-enrolling participating sites. The primary outcome was death from any cause; the secondary outcome was a composite of death from any cause, heart transplantation, or implantation of a ventricular assist device. RESULTS: The trial enrolled 1798 patients, of whom 1050 were included in the long-term survival trial; the median duration of follow-up for the 1050 patients was 7.7 years (interquartile range, 3.9 to 12.8), and the median duration of follow-up for those who survived was 13.9 years (interquartile range, 12.8 to 15.7). Death occurred in 405 of 530 patients (76.4%) assigned to the ICD group and in 370 of 520 patients (71.2%) assigned to the CRT-D group. The time until death appeared to be longer for those assigned to receive a CRT-D than for those assigned to receive an ICD (acceleration factor, 0.80; 95% confidence interval, 0.69 to 0.92; P = 0.002). A secondary-outcome event occurred in 412 patients (77.7%) in the ICD group and in 392 (75.4%) in the CRT-D group. CONCLUSIONS: Among patients with a reduced ejection fraction, a widened QRS complex, and NYHA class II or III heart failure, the survival benefit associated with receipt of a CRT-D as compared with ICD appeared to be sustained during a median of nearly 14 years of follow-up. (RAFT ClinicalTrials.gov number, NCT00251251.).


Assuntos
Terapia de Ressincronização Cardíaca , Desfibriladores Implantáveis , Insuficiência Cardíaca , Humanos , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/terapia , Estimativa de Kaplan-Meier , Volume Sistólico , Resultado do Tratamento , Função Ventricular Esquerda , Eletrocardiografia , Seguimentos , Fatores de Tempo
20.
N Engl J Med ; 390(20): 1849-1861, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38739079

RESUMO

BACKGROUND: One of the major determinants of exercise intolerance and limiting symptoms among patients with obstructive hypertrophic cardiomyopathy (HCM) is an elevated intracardiac pressure resulting from left ventricular outflow tract obstruction. Aficamten is an oral selective cardiac myosin inhibitor that reduces left ventricular outflow tract gradients by mitigating cardiac hypercontractility. METHODS: In this phase 3, double-blind trial, we randomly assigned adults with symptomatic obstructive HCM to receive aficamten (starting dose, 5 mg; maximum dose, 20 mg) or placebo for 24 weeks, with dose adjustment based on echocardiography results. The primary end point was the change from baseline to week 24 in the peak oxygen uptake as assessed by cardiopulmonary exercise testing. The 10 prespecified secondary end points (tested hierarchically) were change in the Kansas City Cardiomyopathy Questionnaire clinical summary score (KCCQ-CSS), improvement in the New York Heart Association (NYHA) functional class, change in the pressure gradient after the Valsalva maneuver, occurrence of a gradient of less than 30 mm Hg after the Valsalva maneuver, and duration of eligibility for septal reduction therapy (all assessed at week 24); change in the KCCQ-CSS, improvement in the NYHA functional class, change in the pressure gradient after the Valsalva maneuver, and occurrence of a gradient of less than 30 mm Hg after the Valsalva maneuver (all assessed at week 12); and change in the total workload as assessed by cardiopulmonary exercise testing at week 24. RESULTS: A total of 282 patients underwent randomization: 142 to the aficamten group and 140 to the placebo group. The mean age was 59.1 years, 59.2% were men, the baseline mean resting left ventricular outflow tract gradient was 55.1 mm Hg, and the baseline mean left ventricular ejection fraction was 74.8%. At 24 weeks, the mean change in the peak oxygen uptake was 1.8 ml per kilogram per minute (95% confidence interval [CI], 1.2 to 2.3) in the aficamten group and 0.0 ml per kilogram per minute (95% CI, -0.5 to 0.5) in the placebo group (least-squares mean between-group difference, 1.7 ml per kilogram per minute; 95% CI, 1.0 to 2.4; P<0.001). The results for all 10 secondary end points were significantly improved with aficamten as compared with placebo. The incidence of adverse events appeared to be similar in the two groups. CONCLUSIONS: Among patients with symptomatic obstructive HCM, treatment with aficamten resulted in a significantly greater improvement in peak oxygen uptake than placebo. (Funded by Cytokinetics; SEQUOIA-HCM ClinicalTrials.gov number, NCT05186818.).


Assuntos
Cardiomiopatia Hipertrófica , Fármacos Cardiovasculares , Teste de Esforço , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Benzilaminas , Miosinas Cardíacas/antagonistas & inibidores , Cardiomiopatia Hipertrófica/tratamento farmacológico , Cardiomiopatia Hipertrófica/fisiopatologia , Método Duplo-Cego , Tolerância ao Exercício/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , Uracila/análogos & derivados , Manobra de Valsalva , Obstrução do Fluxo Ventricular Externo/tratamento farmacológico , Obstrução do Fluxo Ventricular Externo/fisiopatologia , Obstrução do Fluxo Ventricular Externo/etiologia , Fármacos Cardiovasculares/farmacologia , Fármacos Cardiovasculares/uso terapêutico , Contração Miocárdica/efeitos dos fármacos , Contração Miocárdica/fisiologia , Administração Oral
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