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1.
Cell ; 183(2): 537-548.e12, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-33064989

RESUMO

Sequential activation of neurons has been observed during various behavioral and cognitive processes, but the underlying circuit mechanisms remain poorly understood. Here, we investigate premotor sequences in HVC (proper name) of the adult zebra finch forebrain that are central to the performance of the temporally precise courtship song. We use high-density silicon probes to measure song-related population activity, and we compare these observations with predictions from a range of network models. Our results support a circuit architecture in which heterogeneous delays between sequentially active neurons shape the spatiotemporal patterns of HVC premotor neuron activity. We gauge the impact of several delay sources, and we find the primary contributor to be slow conduction through axonal collaterals within HVC, which typically adds between 1 and 7.5 ms for each link within the sequence. Thus, local axonal "delay lines" can play an important role in determining the dynamical repertoire of neural circuits.


Assuntos
Tentilhões/fisiologia , Prosencéfalo/fisiologia , Vocalização Animal/fisiologia , Comunicação Animal , Animais , Axônios , Masculino , Córtex Motor/fisiologia , Rede Nervosa/fisiologia , Vias Neurais/fisiologia , Neurônios/fisiologia
2.
Immunity ; 56(1): 93-106.e6, 2023 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-36574773

RESUMO

Improved identification of anti-tumor T cells is needed to advance cancer immunotherapies. CD39 expression is a promising surrogate of tumor-reactive CD8+ T cells. Here, we comprehensively profiled CD39 expression in human lung cancer. CD39 expression enriched for CD8+ T cells with features of exhaustion, tumor reactivity, and clonal expansion. Flow cytometry of 440 lung cancer biospecimens revealed weak association between CD39+ CD8+ T cells and tumoral features, such as programmed death-ligand 1 (PD-L1), tumor mutation burden, and driver mutations. Immune checkpoint blockade (ICB), but not cytotoxic chemotherapy, increased intratumoral CD39+ CD8+ T cells. Higher baseline frequency of CD39+ CD8+ T cells conferred improved clinical outcomes from ICB therapy. Furthermore, a gene signature of CD39+ CD8+ T cells predicted benefit from ICB, but not chemotherapy, in a phase III clinical trial of non-small cell lung cancer. These findings highlight CD39 as a proxy of tumor-reactive CD8+ T cells in human lung cancer.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Inibidores de Checkpoint Imunológico/uso terapêutico , Linfócitos T CD8-Positivos , Imunoterapia
3.
Cell ; 167(3): 695-708.e16, 2016 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-27745971

RESUMO

Heritability and genome stability are shaped by meiotic recombination, which is initiated via hundreds of DNA double-strand breaks (DSBs). The distribution of DSBs throughout the genome is not random, but mechanisms molding this landscape remain poorly understood. Here, we exploit genome-wide maps of mouse DSBs at unprecedented nucleotide resolution to uncover previously invisible spatial features of recombination. At fine scale, we reveal a stereotyped hotspot structure-DSBs occur within narrow zones between methylated nucleosomes-and identify relationships between SPO11, chromatin, and the histone methyltransferase PRDM9. At large scale, DSB formation is suppressed on non-homologous portions of the sex chromosomes via the DSB-responsive kinase ATM, which also shapes the autosomal DSB landscape at multiple size scales. We also provide a genome-wide analysis of exonucleolytic DSB resection lengths and elucidate spatial relationships between DSBs and recombination products. Our results paint a comprehensive picture of features governing successive steps in mammalian meiotic recombination.


Assuntos
Quebras de DNA de Cadeia Dupla , Reparo do DNA , Instabilidade Genômica/genética , Recombinação Homóloga , Meiose/genética , Animais , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Cromatina/genética , Cromatina/metabolismo , Metilação de DNA , Endodesoxirribonucleases/genética , Endodesoxirribonucleases/metabolismo , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Nucleossomos/enzimologia , Nucleossomos/genética , Cromossomo X/genética , Cromossomo Y/genética
4.
Nature ; 626(8001): 975-978, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38418911

RESUMO

The identification of sources driving cosmic reionization, a major phase transition from neutral hydrogen to ionized plasma around 600-800 Myr after the Big Bang1-3, has been a matter of debate4. Some models suggest that high ionizing emissivity and escape fractions (fesc) from quasars support their role in driving cosmic reionization5,6. Others propose that the high fesc values from bright galaxies generate sufficient ionizing radiation to drive this process7. Finally, a few studies suggest that the number density of faint galaxies, when combined with a stellar-mass-dependent model of ionizing efficiency and fesc, can effectively dominate cosmic reionization8,9. However, so far, comprehensive spectroscopic studies of low-mass galaxies have not been done because of their extreme faintness. Here we report an analysis of eight ultra-faint galaxies (in a very small field) during the epoch of reionization with absolute magnitudes between MUV ≈ -17 mag and -15 mag (down to 0.005L⋆ (refs. 10,11)). We find that faint galaxies during the first thousand million years of the Universe produce ionizing photons with log[ξion (Hz erg-1)] = 25.80 ± 0.14, a factor of 4 higher than commonly assumed values12. If this field is representative of the large-scale distribution of faint galaxies, the rate of ionizing photons exceeds that needed for reionization, even for escape fractions of the order of 5%.

5.
Nature ; 628(8006): 57-61, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38354833

RESUMO

Early JWST observations have uncovered a population of red sources that might represent a previously overlooked phase of supermassive black hole growth1-3. One of the most intriguing examples is an extremely red, point-like object that was found to be triply imaged by the strong lensing cluster Abell 2744 (ref. 4). Here we present deep JWST/NIRSpec observations of this object, Abell2744-QSO1. The spectroscopy confirms that the three images are of the same object, and that it is a highly reddened (AV ≃ 3) broad emission line active galactic nucleus at a redshift of zspec = 7.0451 ± 0.0005. From the width of Hß (full width at half-maximum = 2,800 ± 250 km s-1), we derive a black hole mass of M BH = 4 - 1 + 2 × 1 0 7 M ⊙ . We infer a very high ratio of black-hole-to-galaxy mass of at least 3%, an order of magnitude more than that seen in local galaxies5 and possibly as high as 100%. The lack of strong metal lines in the spectrum together with the high bolometric luminosity (Lbol = (1.1 ± 0.3) × 1045 erg s-1) indicate that we are seeing the black hole in a phase of rapid growth, accreting at 30% of the Eddington limit. The rapid growth and high black-hole-to-galaxy mass ratio of Abell2744-QSO1 suggest that it may represent the missing link between black hole seeds6 and one of the first luminous quasars7.

6.
N Engl J Med ; 390(6): 497-509, 2024 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-38324483

RESUMO

BACKGROUND: Nonalcoholic steatohepatitis (NASH) is a progressive liver disease with no approved treatment. Resmetirom is an oral, liver-directed, thyroid hormone receptor beta-selective agonist in development for the treatment of NASH with liver fibrosis. METHODS: We are conducting an ongoing phase 3 trial involving adults with biopsy-confirmed NASH and a fibrosis stage of F1B, F2, or F3 (stages range from F0 [no fibrosis] to F4 [cirrhosis]). Patients were randomly assigned in a 1:1:1 ratio to receive once-daily resmetirom at a dose of 80 mg or 100 mg or placebo. The two primary end points at week 52 were NASH resolution (including a reduction in the nonalcoholic fatty liver disease [NAFLD] activity score by ≥2 points; scores range from 0 to 8, with higher scores indicating more severe disease) with no worsening of fibrosis, and an improvement (reduction) in fibrosis by at least one stage with no worsening of the NAFLD activity score. RESULTS: Overall, 966 patients formed the primary analysis population (322 in the 80-mg resmetirom group, 323 in the 100-mg resmetirom group, and 321 in the placebo group). NASH resolution with no worsening of fibrosis was achieved in 25.9% of the patients in the 80-mg resmetirom group and 29.9% of those in the 100-mg resmetirom group, as compared with 9.7% of those in the placebo group (P<0.001 for both comparisons with placebo). Fibrosis improvement by at least one stage with no worsening of the NAFLD activity score was achieved in 24.2% of the patients in the 80-mg resmetirom group and 25.9% of those in the 100-mg resmetirom group, as compared with 14.2% of those in the placebo group (P<0.001 for both comparisons with placebo). The change in low-density lipoprotein cholesterol levels from baseline to week 24 was -13.6% in the 80-mg resmetirom group and -16.3% in the 100-mg resmetirom group, as compared with 0.1% in the placebo group (P<0.001 for both comparisons with placebo). Diarrhea and nausea were more frequent with resmetirom than with placebo. The incidence of serious adverse events was similar across trial groups: 10.9% in the 80-mg resmetirom group, 12.7% in the 100-mg resmetirom group, and 11.5% in the placebo group. CONCLUSIONS: Both the 80-mg dose and the 100-mg dose of resmetirom were superior to placebo with respect to NASH resolution and improvement in liver fibrosis by at least one stage. (Funded by Madrigal Pharmaceuticals; MAESTRO-NASH ClinicalTrials.gov number, NCT03900429.).


Assuntos
Cirrose Hepática , Hepatopatia Gordurosa não Alcoólica , Piridazinas , Uracila , Adulto , Humanos , Método Duplo-Cego , Fígado/diagnóstico por imagem , Fígado/efeitos dos fármacos , Fígado/patologia , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/etiologia , Cirrose Hepática/patologia , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/patologia , Piridazinas/uso terapêutico , Resultado do Tratamento , Uracila/análogos & derivados , Receptores beta dos Hormônios Tireóideos/agonistas , Biópsia , Relação Dose-Resposta a Droga
7.
Nature ; 596(7870): 58-62, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34349289

RESUMO

Macroscale analogues1-3 of microscopic spin systems offer direct insights into fundamental physical principles, thereby advancing our understanding of synchronization phenomena4 and informing the design of novel classes of chiral metamaterials5-7. Here we introduce hydrodynamic spin lattices (HSLs) of 'walking' droplets as a class of active spin systems with particle-wave coupling. HSLs reveal various non-equilibrium symmetry-breaking phenomena, including transitions from antiferromagnetic to ferromagnetic order that can be controlled by varying the lattice geometry and system rotation8. Theoretical predictions based on a generalized Kuramoto model4 derived from first principles rationalize our experimental observations, establishing HSLs as a versatile platform for exploring active phase oscillator dynamics. The tunability of HSLs suggests exciting directions for future research, from active spin-wave dynamics to hydrodynamic analogue computation and droplet-based topological insulators.

8.
Cell ; 144(5): 719-31, 2011 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-21376234

RESUMO

The nonrandom distribution of meiotic recombination influences patterns of inheritance and genome evolution, but chromosomal features governing this distribution are poorly understood. Formation of the DNA double-strand breaks (DSBs) that initiate recombination results in the accumulation of Spo11 protein covalently bound to small DNA fragments. By sequencing these fragments, we uncover a genome-wide DSB map of unprecedented resolution and sensitivity. We use this map to explore how DSB distribution is influenced by large-scale chromosome structures, chromatin, transcription factors, and local sequence composition. Our analysis offers mechanistic insight into DSB formation and early processing steps, supporting the view that the recombination terrain is molded by combinatorial and hierarchical interaction of factors that work on widely different size scales. This map illuminates the occurrence of DSBs in repetitive DNA elements, repair of which can lead to chromosomal rearrangements. We also discuss implications for evolutionary dynamics of recombination hot spots.


Assuntos
Genoma Fúngico , Saccharomyces cerevisiae/genética , Quebras de DNA de Cadeia Dupla , Endodesoxirribonucleases/metabolismo , Estudo de Associação Genômica Ampla , Recombinação Genética , Proteínas de Saccharomyces cerevisiae/metabolismo
9.
Microbiology (Reading) ; 170(7)2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39073401

RESUMO

Sponges (phylum Porifera) harbour specific microbial communities that drive the ecology and evolution of the host. Understanding the structure and dynamics of these communities is emerging as a primary focus in marine microbial ecology research. Much of the work to date has focused on sponges from warm and shallow coastal waters, while sponges from the deep ocean remain less well studied. Here, we present a metataxonomic analysis of the microbial consortia associated with 23 individual deep-sea sponges. We identify a high abundance of archaea relative to bacteria across these communities, with certain sponge microbiomes comprising more than 90 % archaea. Specifically, the archaeal family Nitrosopumilaceae is prolific, comprising over 99 % of all archaeal reads. Our analysis revealed that sponge microbial communities reflect the host sponge phylogeny, indicating a key role for host taxonomy in defining microbiome composition. Our work confirms the contribution of both evolutionary and environmental processes to the composition of microbial communities in deep-sea sponges.


Assuntos
Archaea , Bactérias , Microbiota , Filogenia , Poríferos , Poríferos/microbiologia , Archaea/classificação , Archaea/genética , Archaea/isolamento & purificação , Animais , Oceano Atlântico , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Água do Mar/microbiologia , RNA Ribossômico 16S/genética , Biodiversidade
10.
Proc Natl Acad Sci U S A ; 118(11)2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33649183

RESUMO

For the first time in history, automated vehicles (AVs) are being deployed in populated environments. This unprecedented transformation of our everyday lives demands a significant undertaking: endowing complex autonomous systems with ethically acceptable behavior. We outline how one prominent, ethically relevant component of AVs-driving behavior-is inextricably linked to stakeholders in the technical, regulatory, and social spheres of the field. Whereas humans are presumed (rightly or wrongly) to have the "common sense" to behave ethically in new driving situations beyond a standard driving test, AVs do not (and probably should not) enjoy this presumption. We examine, at a high level, how to test the common sense of an AV. We start by reviewing discussions of "driverless dilemmas," adaptions of the traditional "trolley dilemmas" of philosophy that have sparked discussion on AV ethics but have limited use to the technical and legal spheres. Then, we explain how to substantially change the premises and features of these dilemmas (while preserving their behavioral diagnostic spirit) in order to lay the foundations for a more practical and relevant framework that tests driving common sense as an integral part of road rules testing.

11.
Proc Natl Acad Sci U S A ; 118(13)2021 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-33753493

RESUMO

Conventional T cell fate and function are determined by coordination between cellular signaling and mitochondrial metabolism. Invariant natural killer T (iNKT) cells are an important subset of "innate-like" T cells that exist in a preactivated effector state, and their dependence on mitochondrial metabolism has not been previously defined genetically or in vivo. Here, we show that mature iNKT cells have reduced mitochondrial respiratory reserve and iNKT cell development was highly sensitive to perturbation of mitochondrial function. Mice with T cell-specific ablation of Rieske iron-sulfur protein (RISP; T-Uqcrfs1-/- ), an essential subunit of mitochondrial complex III, had a dramatic reduction of iNKT cells in the thymus and periphery, but no significant perturbation on the development of conventional T cells. The impaired development observed in T-Uqcrfs1-/- mice stems from a cell-autonomous defect in iNKT cells, resulting in a differentiation block at the early stages of iNKT cell development. Residual iNKT cells in T-Uqcrfs1-/- mice displayed increased apoptosis but retained the ability to proliferate in vivo, suggesting that their bioenergetic and biosynthetic demands were not compromised. However, they exhibited reduced expression of activation markers, decreased T cell receptor (TCR) signaling and impaired responses to TCR and interleukin-15 stimulation. Furthermore, knocking down RISP in mature iNKT cells diminished their cytokine production, correlating with reduced NFATc2 activity. Collectively, our data provide evidence for a critical role of mitochondrial metabolism in iNKT cell development and activation outside of its traditional role in supporting cellular bioenergetic demands.


Assuntos
Metabolismo Energético/fisiologia , Mitocôndrias/metabolismo , Células T Matadoras Naturais/fisiologia , Animais , Antígenos CD1d/metabolismo , Diferenciação Celular , Complexo III da Cadeia de Transporte de Elétrons/deficiência , Complexo III da Cadeia de Transporte de Elétrons/genética , Técnicas de Silenciamento de Genes , Interleucina-15/metabolismo , Proteínas Ferro-Enxofre/genética , Ativação Linfocitária , Camundongos , Camundongos Knockout , Células T Matadoras Naturais/citologia
12.
J Sports Sci ; : 1-12, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38916272

RESUMO

The activities soccer players engage in during their formative years are thought to significantly contribute to the acquisition of expert performance. Whilst this area has seen great interest in male players, there has been little research in females. The study examined developmental activities engaged in by professional female soccer players in England. 56 female soccer players that had either progressed to professional status in adulthood (professional), or did not (ex-academy), completed the Participant History Questionnaire. Professional players started engaging in soccer at an earlier age than their ex-academy counterparts, resulting in greater engagement in practice and play during childhood. During adolescence, professional players engaged in higher amounts of practice than ex-academy players. Engagement in competition and practice was rated as high in physical and cognitive effort by all, yet ex-academy players reported higher levels of physical effort during early adolescence, and cognitive effort during late adolescence. Findings provide an illustration of the talent pathways of professional female soccer players in England and may inform future talent development systems. Large interindividual variation in soccer-specific and other-sport activity data highlight the importance of further understanding the environments of individual soccer nations and their potential impact on the talent identification and development processes.

13.
Clin Immunol ; 252: 109634, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37150240

RESUMO

Over two years into the COVID-19 pandemic, the human immune response to SARS-CoV-2 during the active disease phase has been extensively studied. However, the long-term impact after recovery, which is critical to advance our understanding SARS-CoV-2 and COVID-19-associated long-term complications, remains largely unknown. Herein, we characterized single-cell profiles of circulating immune cells in the peripheral blood of 100 patients, including convalescent COVID-19 and sero-negative controls. Flow cytometry analyses revealed reduced frequencies of both short-lived monocytes and long-lived regulatory T (Treg) cells within the patients who have recovered from severe COVID-19. sc-RNA seq analysis identifies seven heterogeneous clusters of monocytes and nine Treg clusters featuring distinct molecular signatures in association with COVID-19 severity. Asymptomatic patients contain the most abundant clusters of monocytes and Tregs expressing high CD74 or IFN-responsive genes. In contrast, the patients recovered from a severe disease have shown two dominant inflammatory monocyte clusters featuring S100 family genes: one monocyte cluster of S100A8 & A9 coupled with high HLA-I and another cluster of S100A4 & A6 with high HLA-II genes, a specific non-classical monocyte cluster with distinct IFITM family genes, as well as a unique TGF-ß high Treg Cluster. The outpatients and seronegative controls share most of the monocyte and Treg clusters patterns with high expression of HLA genes. Surprisingly, while presumably short-lived monocytes appear to have sustained alterations over 4 months, the decreased frequencies of long-lived Tregs (high HLA-DRA and S100A6) in the outpatients restore over the tested convalescent time (≥ 4 months). Collectively, our study identifies sustained and dynamically altered monocytes and Treg clusters with distinct molecular signatures after recovery, associated with COVID-19 severity.


Assuntos
COVID-19 , Monócitos , Humanos , COVID-19/metabolismo , Linfócitos T Reguladores , Pandemias , SARS-CoV-2
14.
Ann Surg ; 277(3): e569-e577, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34387206

RESUMO

OBJECTIVE: Rapid evaporative ionization mass spectrometry (REIMS) is a metabolomic technique analyzing tissue metabolites, which can be applied intraoperatively in real-time. The objective of this study was to profile the lipid composition of colorectal tissues using REIMS, assessing its accuracy for real-time tissue recognition and risk-stratification. SUMMARY BACKGROUND DATA: Metabolic dysregulation is a hallmark feature of carcinogenesis; however, it remains unknown if this can be leveraged for real-time clinical applications in colorectal disease. METHODS: Patients undergoing colorectal resection were included, with carcinoma, adenoma and paired-normal mucosa sampled. Ex vivo analysis with REIMS was conducted using monopolar diathermy, with the aerosol aspirated into a Xevo G2S QToF mass spectrometer. Negatively charged ions over 600 to 1000 m/z were used for univariate and multivariate functions including linear discriminant analysis. RESULTS: A total of 161 patients were included, generating 1013 spectra. Unique lipidomic profiles exist for each tissue type, with REIMS differentiating samples of carcinoma, adenoma, and normal mucosa with 93.1% accuracy and 96.1% negative predictive value for carcinoma. Neoplasia (carcinoma or adenoma) could be predicted with 96.0% accuracy and 91.8% negative predictive value. Adenomas can be risk-stratified by grade of dysplasia with 93.5% accuracy, but not histological subtype. The structure of 61 lipid metabolites was identified, revealing that during colorectal carcinogenesis there is progressive increase in relative abundance of phosphatidylglycerols, sphingomyelins, and mono-unsaturated fatty acid-containing phospholipids. CONCLUSIONS: The colorectal lipidome can be sampled by REIMS and leveraged for accurate real-time tissue recognition, in addition to riskstratification of colorectal adenomas. Unique lipidomic features associated with carcinogenesis are described.


Assuntos
Adenoma , Carcinoma , Neoplasias Colorretais , Humanos , Lipidômica , Espectrometria de Massas , Neoplasias Colorretais/patologia , Lipídeos , Carcinogênese , Adenoma/diagnóstico , Adenoma/cirurgia , Adenoma/metabolismo
15.
Chembiochem ; 24(14): e202300382, 2023 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-37305956

RESUMO

Stereoselective carbon-carbon bond forming reactions are quintessential transformations in organic synthesis. One example is the Diels-Alder reaction, a [4+2] cycloaddition between a conjugated diene and a dienophile to form cyclohexenes. The development of biocatalysts for this reaction is paramount for unlocking sustainable routes to a plethora of important molecules. To obtain a comprehensive understanding of naturally evolved [4+2] cyclases, and to identify hitherto uncharacterised biocatalysts for this reaction, we constructed a library comprising forty-five enzymes with reported or predicted [4+2] cycloaddition activity. Thirty-one library members were successfully produced in recombinant form. In vitro assays employing a synthetic substrate incorporating a diene and a dienophile revealed broad-ranging cycloaddition activity amongst these polypeptides. The hypothetical protein Cyc15 was found to catalyse an intramolecular cycloaddition to generate a novel spirotetronate. The crystal structure of this enzyme, along with docking studies, establishes the basis for stereoselectivity in Cyc15, as compared to other spirotetronate cyclases.


Assuntos
Carbono , Proteínas , Catálise , Reação de Cicloadição , Técnicas de Química Sintética
16.
J Psychiatry Neurosci ; 48(3): E190-E208, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37253482

RESUMO

Environment is known to substantially alter mental state and behaviour across the lifespan. Biological barriers such as the blood-brain barrier (BBB) and gut barrier (GB) are major hubs for communication of environmental information. Alterations in the structural, social and motor environment at different stages of life can influence function of the BBB and GB and their integrity to exert behavioural consequences. Importantly, each of these environmental components is associated with a distinct immune profile, glucocorticoid response and gut microbiome composition, creating unique effects on the BBB and GB. These barrier-environment interactions are sensitive to change throughout life, and positive or negative alterations at critical stages of development can exert long-lasting cognitive and behavioural consequences. Furthermore, because loss of barrier integrity is implicated in pathogenesis of mental disorders, the pathways of environmental influence represent important areas for understanding these diseases. Positive environments can be protective against stress- and age-related damage, raising the possibility of novel pharmacological targets. This review summarizes known mechanisms of environmental influence - such as social interactions, structural complexity and physical exercise - on barrier composition, morphology and development, and considers the outcomes and implications of these interactions in the context of psychiatric disorders.


Assuntos
Eixo Encéfalo-Intestino , Longevidade , Humanos , Interação Gene-Ambiente , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/patologia , Cognição , Encéfalo/metabolismo
18.
Pediatr Neurosurg ; 58(5): 313-336, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36549282

RESUMO

BACKGROUND: Brain tumors are the most common solid tumors and the leading cause of cancer-related deaths in children. Incidence in the USA has been on the rise for the last 2 decades. While therapeutic advances in diagnosis and treatment have improved survival and quality of life in many children, prognosis remains poor and current treatments have significant long-term sequelae. SUMMARY: There is a substantial need for the development of new therapeutic approaches, and since the introduction of immunotherapy by immune checkpoint inhibitors, there has been an exponential increase in clinical trials to adopt these and other immunotherapy approaches in children with brain tumors. In this review, we summarize the current immunotherapy landscape for various pediatric brain tumor types including choroid plexus tumors, embryonal tumors (medulloblastoma, AT/RT, PNETs), ependymoma, germ cell tumors, gliomas, glioneuronal and neuronal tumors, and mesenchymal tumors. We discuss the latest clinical trials and noteworthy preclinical studies to treat these pediatric brain tumors using checkpoint inhibitors, cellular therapies (CAR-T, NK, T cell), oncolytic virotherapy, radioimmunotherapy, tumor vaccines, immunomodulators, and other targeted therapies. KEY MESSAGES: The current landscape for immunotherapy in pediatric brain tumors is still emerging, but results in certain tumors have been promising. In the age of targeted therapy, genetic tumor profiling, and many ongoing clinical trials, immunotherapy will likely become an increasingly effective tool in the neuro-oncologist armamentarium.


Assuntos
Neoplasias Encefálicas , Neoplasias Cerebelares , Humanos , Criança , Qualidade de Vida , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/patologia , Imunoterapia/métodos , Encéfalo/patologia
19.
Sensors (Basel) ; 23(2)2023 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-36679761

RESUMO

The design of blast-resistant structures and protective systems requires a firm understanding of the loadings imparted to structures by blast waves. While empirical methods can reliably predict these loadings in the far field, there is currently a lack of understanding on the pressures experienced in the very near field, where physics-based numerical modelling and semi-empirical fast-running engineering model predictions can vary by an order of magnitude. In this paper, we present the design of an experimental facility capable of providing definitive spatially and temporally resolved reflected pressure data in the extreme near field (Z<0.5 m/kg1/3). The Mechanisms and Characterisation of Explosions (MaCE) facility is a specific near-field evolution of the existing Characterisation of Blast Loading (CoBL) facility, which uses an array of Hopkinson pressure bars embedded in a stiff target plate. Maraging steel pressure bars and specially designed strain gauges are used to increase the measurement capacity from 600 MPa to 1800 MPa, and 33 pressure bars in a radial grid are used to improve the spatial resolution from 25 mm to 12.5 mm over the 100 mm radius measurement area. In addition, the pressure bar diameter is reduced from 10 mm to 4 mm, which greatly reduces stress wave dispersion, increasing the effective bandwidth. This enables the observation of high-frequency features in the pressure measurements, which is vital for validating the near-field transient effects predicted by numerical modelling and developing effective blast mitigation methods.


Assuntos
Explosões , Pressão
20.
JAMA ; 329(1): 39-51, 2023 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-36525245

RESUMO

Importance: The longer-term effects of therapies for the treatment of critically ill patients with COVID-19 are unknown. Objective: To determine the effect of multiple interventions for critically ill adults with COVID-19 on longer-term outcomes. Design, Setting, and Participants: Prespecified secondary analysis of an ongoing adaptive platform trial (REMAP-CAP) testing interventions within multiple therapeutic domains in which 4869 critically ill adult patients with COVID-19 were enrolled between March 9, 2020, and June 22, 2021, from 197 sites in 14 countries. The final 180-day follow-up was completed on March 2, 2022. Interventions: Patients were randomized to receive 1 or more interventions within 6 treatment domains: immune modulators (n = 2274), convalescent plasma (n = 2011), antiplatelet therapy (n = 1557), anticoagulation (n = 1033), antivirals (n = 726), and corticosteroids (n = 401). Main Outcomes and Measures: The main outcome was survival through day 180, analyzed using a bayesian piecewise exponential model. A hazard ratio (HR) less than 1 represented improved survival (superiority), while an HR greater than 1 represented worsened survival (harm); futility was represented by a relative improvement less than 20% in outcome, shown by an HR greater than 0.83. Results: Among 4869 randomized patients (mean age, 59.3 years; 1537 [32.1%] women), 4107 (84.3%) had known vital status and 2590 (63.1%) were alive at day 180. IL-6 receptor antagonists had a greater than 99.9% probability of improving 6-month survival (adjusted HR, 0.74 [95% credible interval {CrI}, 0.61-0.90]) and antiplatelet agents had a 95% probability of improving 6-month survival (adjusted HR, 0.85 [95% CrI, 0.71-1.03]) compared with the control, while the probability of trial-defined statistical futility (HR >0.83) was high for therapeutic anticoagulation (99.9%; HR, 1.13 [95% CrI, 0.93-1.42]), convalescent plasma (99.2%; HR, 0.99 [95% CrI, 0.86-1.14]), and lopinavir-ritonavir (96.6%; HR, 1.06 [95% CrI, 0.82-1.38]) and the probabilities of harm from hydroxychloroquine (96.9%; HR, 1.51 [95% CrI, 0.98-2.29]) and the combination of lopinavir-ritonavir and hydroxychloroquine (96.8%; HR, 1.61 [95% CrI, 0.97-2.67]) were high. The corticosteroid domain was stopped early prior to reaching a predefined statistical trigger; there was a 57.1% to 61.6% probability of improving 6-month survival across varying hydrocortisone dosing strategies. Conclusions and Relevance: Among critically ill patients with COVID-19 randomized to receive 1 or more therapeutic interventions, treatment with an IL-6 receptor antagonist had a greater than 99.9% probability of improved 180-day mortality compared with patients randomized to the control, and treatment with an antiplatelet had a 95.0% probability of improved 180-day mortality compared with patients randomized to the control. Overall, when considered with previously reported short-term results, the findings indicate that initial in-hospital treatment effects were consistent for most therapies through 6 months.


Assuntos
COVID-19 , Adulto , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Lopinavir/uso terapêutico , Ritonavir/uso terapêutico , Seguimentos , Hidroxicloroquina/uso terapêutico , SARS-CoV-2 , Estado Terminal/terapia , Teorema de Bayes , Soroterapia para COVID-19 , Corticosteroides/uso terapêutico , Anticoagulantes/efeitos adversos , Receptores de Interleucina-6
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