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1.
Genes Dev ; 34(5-6): 428-445, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-32001510

RESUMO

Cellular senescence is a potent tumor suppressor mechanism but also contributes to aging and aging-related diseases. Senescence is characterized by a stable cell cycle arrest and a complex proinflammatory secretome, termed the senescence-associated secretory phenotype (SASP). We recently discovered that cytoplasmic chromatin fragments (CCFs), extruded from the nucleus of senescent cells, trigger the SASP through activation of the innate immunity cytosolic DNA sensing cGAS-STING pathway. However, the upstream signaling events that instigate CCF formation remain unknown. Here, we show that dysfunctional mitochondria, linked to down-regulation of nuclear-encoded mitochondrial oxidative phosphorylation genes, trigger a ROS-JNK retrograde signaling pathway that drives CCF formation and hence the SASP. JNK links to 53BP1, a nuclear protein that negatively regulates DNA double-strand break (DSB) end resection and CCF formation. Importantly, we show that low-dose HDAC inhibitors restore expression of most nuclear-encoded mitochondrial oxidative phosphorylation genes, improve mitochondrial function, and suppress CCFs and the SASP in senescent cells. In mouse models, HDAC inhibitors also suppress oxidative stress, CCF, inflammation, and tissue damage caused by senescence-inducing irradiation and/or acetaminophen-induced mitochondria dysfunction. Overall, our findings outline an extended mitochondria-to-nucleus retrograde signaling pathway that initiates formation of CCF during senescence and is a potential target for drug-based interventions to inhibit the proaging SASP.


Assuntos
Núcleo Celular/patologia , Senescência Celular/fisiologia , Cromatina/patologia , Citoplasma/patologia , Mitocôndrias/patologia , Transdução de Sinais , Animais , Núcleo Celular/fisiologia , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Humanos , Inflamação/fisiopatologia , Sistema de Sinalização das MAP Quinases/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/metabolismo
2.
Nature ; 594(7863): 430-435, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34079124

RESUMO

The tumour suppressor APC is the most commonly mutated gene in colorectal cancer. Loss of Apc in intestinal stem cells drives the formation of adenomas in mice via increased WNT signalling1, but reduced secretion of WNT ligands increases the ability of Apc-mutant intestinal stem cells to colonize a crypt (known as fixation)2. Here we investigated how Apc-mutant cells gain a clonal advantage over wild-type counterparts to achieve fixation. We found that Apc-mutant cells are enriched for transcripts that encode several secreted WNT antagonists, with Notum being the most highly expressed. Conditioned medium from Apc-mutant cells suppressed the growth of wild-type organoids in a NOTUM-dependent manner. Furthermore, NOTUM-secreting Apc-mutant clones actively inhibited the proliferation of surrounding wild-type crypt cells and drove their differentiation, thereby outcompeting crypt cells from the niche. Genetic or pharmacological inhibition of NOTUM abrogated the ability of Apc-mutant cells to expand and form intestinal adenomas. We identify NOTUM as a key mediator during the early stages of mutation fixation that can be targeted to restore wild-type cell competitiveness and provide preventative strategies for people at a high risk of developing colorectal cancer.


Assuntos
Competição entre as Células , Transformação Celular Neoplásica , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Esterases/metabolismo , Genes APC , Mutação , Adenoma/genética , Adenoma/patologia , Proteína da Polipose Adenomatosa do Colo/genética , Animais , Competição entre as Células/genética , Diferenciação Celular , Proliferação de Células , Transformação Celular Neoplásica/genética , Meios de Cultivo Condicionados , Progressão da Doença , Esterases/antagonistas & inibidores , Esterases/genética , Feminino , Humanos , Ligantes , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Organoides/citologia , Organoides/metabolismo , Organoides/patologia , Células-Tronco/citologia , Células-Tronco/metabolismo , Proteínas Wnt/metabolismo , Via de Sinalização Wnt
3.
Proc Natl Acad Sci U S A ; 121(7): e2313752121, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38324571

RESUMO

Schelling's 1971 work on the dynamics of segregation showed that even a small degree of homophily, the desire to live among like neighbors, can lead to a starkly segregated population. One of the driving factors for this result is that the notion of homophily used is based on group identities that are exogenous and immutable. In contrast, we consider a homophily that arises from the desire to be with neighbors who are behaviorally similar, not necessarily those who have the same group identity. The distinction matters because behaviors are neither exogenous nor immutable but choices that can change as individuals adapt to their neighborhoods. We show that in such an environment, integration rather than segregation is the typical outcome. However, the tendency toward adaptation and integration can be impeded when economic frictions in the form of income inequality and housing cost are present.


Assuntos
Habitação , Características de Residência , Humanos , Renda
4.
Proc Natl Acad Sci U S A ; 121(3): e2206193121, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38190541

RESUMO

To understand the implications of migration for sustainable development requires a comprehensive consideration of a range of population movements and their feedback across space and time. This Perspective reviews emerging science at the interface of migration studies, demography, and sustainability, focusing on consequences of migration flows for nature-society interactions including on societal outcomes such as inequality; environmental causes and consequences of involuntary displacement; and processes of cultural convergence in sustainability practices in dynamic new populations. We advance a framework that demonstrates how migration outcomes result in identifiable consequences on resources, environmental burdens and well-being, and on innovation, adaptation, and challenges for sustainability governance. We elaborate the research frontiers of migration for sustainability science, explicitly integrating the full spectrum of regular migration decisions dominated by economic motives through to involuntary displacement due to social or environmental stresses. Migration can potentially contribute to sustainability transitions when it enhances well-being while not exacerbating structural inequalities or compound uneven burdens on environmental resources.


Assuntos
Motivação , Desenvolvimento Sustentável , Movimento
5.
N Engl J Med ; 388(25): 2338-2348, 2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37342922

RESUMO

BACKGROUND: In patients undergoing allogeneic hematopoietic stem-cell transplantation (HSCT), a calcineurin inhibitor plus methotrexate has been a standard prophylaxis against graft-versus-host disease (GVHD). A phase 2 study indicated the potential superiority of a post-transplantation regimen of cyclophosphamide, tacrolimus, and mycophenolate mofetil. METHODS: In a phase 3 trial, we randomly assigned adults with hematologic cancers in a 1:1 ratio to receive cyclophosphamide-tacrolimus-mycophenolate mofetil (experimental prophylaxis) or tacrolimus-methotrexate (standard prophylaxis). The patients underwent HSCT from an HLA-matched related donor or a matched or 7/8 mismatched (i.e., mismatched at only one of the HLA-A, HLA-B, HLA-C, and HLA-DRB1 loci) unrelated donor, after reduced-intensity conditioning. The primary end point was GVHD-free, relapse-free survival at 1 year, assessed in a time-to-event analysis, with events defined as grade III or IV acute GVHD, chronic GVHD warranting systemic immunosuppression, disease relapse or progression, and death from any cause. RESULTS: In a multivariate Cox regression analysis, GVHD-free, relapse-free survival was significantly more common among the 214 patients in the experimental-prophylaxis group than among the 217 patients in the standard-prophylaxis group (hazard ratio for grade III or IV acute GVHD, chronic GVHD, disease relapse or progression, or death, 0.64; 95% confidence interval [CI], 0.49 to 0.83; P = 0.001). At 1 year, the adjusted GVHD-free, relapse-free survival was 52.7% (95% CI, 45.8 to 59.2) with experimental prophylaxis and 34.9% (95% CI, 28.6 to 41.3) with standard prophylaxis. Patients in the experimental-prophylaxis group appeared to have less severe acute or chronic GVHD and a higher incidence of immunosuppression-free survival at 1 year. Overall and disease-free survival, relapse, transplantation-related death, and engraftment did not differ substantially between the groups. CONCLUSIONS: Among patients undergoing allogeneic HLA-matched HSCT with reduced-intensity conditioning, GVHD-free, relapse-free survival at 1 year was significantly more common among those who received cyclophosphamide-tacrolimus-mycophenolate mofetil than among those who received tacrolimus-methotrexate. (Funded by the National Heart, Lung, and Blood Institute and others; BMT CTN 1703 ClinicalTrials.gov number, NCT03959241.).


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Síndrome de Bronquiolite Obliterante , Ciclofosfamida , Doença Enxerto-Hospedeiro , Neoplasias Hematológicas , Transplante de Células-Tronco Hematopoéticas , Adulto , Humanos , Síndrome de Bronquiolite Obliterante/etiologia , Síndrome de Bronquiolite Obliterante/prevenção & controle , Ciclofosfamida/administração & dosagem , Doença Enxerto-Hospedeiro/prevenção & controle , Doença Enxerto-Hospedeiro/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/métodos , Metotrexato/administração & dosagem , Ácido Micofenólico/administração & dosagem , Recidiva Local de Neoplasia/tratamento farmacológico , Tacrolimo/administração & dosagem , Doadores não Relacionados , Neoplasias Hematológicas/cirurgia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
6.
Proc Natl Acad Sci U S A ; 120(47): e2310070120, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37956298

RESUMO

The need for faster and deeper transitions toward more sustainable development pathways is now widely recognized. How to meet that need has been at the center of a growing body of academic research and real-world policy implementation. This paper presents our perspective on some of the most powerful insights that have emerged from this ongoing work. In particular, we highlight insights on how sustainability transitions can be usefully conceptualized, how they come about and evolve, and how they can be shaped and guided through deliberate policy interventions. Throughout the paper, we also highlight some of the many how questions that remain unresolved and on which progress would be especially helpful for the pursuit of sustainable development. Our approach to these "how" questions on sustainability transitions draws on two strands of solution-driven research and policy advice: one emerging from studies of how human societies interact with nature and the other emerging from studies of how those societies interact with their technologies. Consumption-production systems have been a focus of extensive work in both strands. To help build bridges between them, we recently brought together a cross-section of relevant scholars for a PNAS Special Feature on "Sustainability transitions in consumption-production systems." Their contributions are summarized in a companion paper we have written to introduce the Special Feature [F. W. Geels, F. Kern, W. C. Clark, Proc. Natl. Acad. Sci. U.S.A. (2023)]. We draw on that work in the Perspective we present here as well as our reading of the relevant literatures.

7.
Proc Natl Acad Sci U S A ; 120(40): e2216656120, 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37751553

RESUMO

This Perspective evaluates recent progress in modeling nature-society systems to inform sustainable development. We argue that recent work has begun to address longstanding and often-cited challenges in bringing modeling to bear on problems of sustainable development. For each of four stages of modeling practice-defining purpose, selecting components, analyzing interactions, and assessing interventions-we highlight examples of dynamical modeling methods and advances in their application that have improved understanding and begun to inform action. Because many of these methods and associated advances have focused on particular sectors and places, their potential to inform key open questions in the field of sustainability science is often underappreciated. We discuss how application of such methods helps researchers interested in harnessing insights into specific sectors and locations to address human well-being, focus on sustainability-relevant timescales, and attend to power differentials among actors. In parallel, application of these modeling methods is helping to advance theory of nature-society systems by enhancing the uptake and utility of frameworks, clarifying key concepts through more rigorous definitions, and informing development of archetypes that can assist hypothesis development and testing. We conclude by suggesting ways to further leverage emerging modeling methods in the context of sustainability science.

8.
Mol Cell ; 66(4): 517-532.e9, 2017 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-28525743

RESUMO

Autophagy is a membrane-trafficking process that directs degradation of cytoplasmic material in lysosomes. The process promotes cellular fidelity, and while the core machinery of autophagy is known, the mechanisms that promote and sustain autophagy are less well defined. Here we report that the epigenetic reader BRD4 and the methyltransferase G9a repress a TFEB/TFE3/MITF-independent transcriptional program that promotes autophagy and lysosome biogenesis. We show that BRD4 knockdown induces autophagy in vitro and in vivo in response to some, but not all, situations. In the case of starvation, a signaling cascade involving AMPK and histone deacetylase SIRT1 displaces chromatin-bound BRD4, instigating autophagy gene activation and cell survival. Importantly, this program is directed independently and also reciprocally to the growth-promoting properties of BRD4 and is potently repressed by BRD4-NUT, a driver of NUT midline carcinoma. These findings therefore identify a distinct and selective mechanism of autophagy regulation.


Assuntos
Autofagia , Carcinoma Ductal Pancreático/metabolismo , Lisossomos/metabolismo , Proteínas Nucleares/metabolismo , Neoplasias Pancreáticas/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Gênica , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Cromatina/genética , Cromatina/metabolismo , Regulação para Baixo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Metabolismo Energético , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Antígenos de Histocompatibilidade/genética , Antígenos de Histocompatibilidade/metabolismo , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Humanos , Lisossomos/patologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas Nucleares/genética , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Agregados Proteicos , Ligação Proteica , Proteólise , Interferência de RNA , Transdução de Sinais , Sirtuína 1/genética , Sirtuína 1/metabolismo , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Fatores de Tempo , Fatores de Transcrição/genética , Transfecção
9.
Crit Rev Biotechnol ; 44(2): 236-254, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36642423

RESUMO

Nowadays, rapidly increasing production, use and disposable of plastic products has become one of the utmost environmental issues. Our current circumstances in which the food supply chain is demonstrated as containing plastic particles and other plastic-based impurities, represents a significant health risk to humans, animals, and environmental alike. According to this point of view, biodegradable plastic material aims to produce a more sustainable and greener world with a lower ecological impact. Bioplastics are being investigated as an environmentally friendly candidate to address this problem and hence global bioplastic production has seen significant growth and expansion in recent years. This article focuses on a few critical issues that must be addressed for bioplastic production to become commercially viable. Although the reduction of fruit and vegetable waste biomass has an apparent value in terms of environmental benefits and sustainability, commercial success at industrial scale has remained flat. This is due to various factors, including biomass feedstocks, pretreatment technologies, enzymatic hydrolysis, and scale-up issues in the industry, all of which contribute to high capital and operating costs. This review paper summarizes the global overview of bioplastics derived from fruit and vegetable waste biomass. Furthermore, economic and technical challenges associated with industrialization and diverse applications of bioplastics in biomedical, agricultural, and food-packaging fields due to their excellent biocompatibility properties are reviewed.HighlightsReview of the diverse types and characteristics of sustainability of biobased plasticsImproved pretreatment technologies can develop to enhance greater yieldEnzyme hydrolysis process used for bioplastic extraction & hasten industrial scale-upFocus on technical challenges facing commercialized the bioplasticsDetailed discussion on the application for sustainability of biodegradable plastics.


Assuntos
Frutas , Verduras , Animais , Humanos , Plásticos , Biopolímeros
10.
Artigo em Inglês | MEDLINE | ID: mdl-38621759

RESUMO

Adsorption-based extracorporeal therapies have been subject to technical developments and clinical application for close to five decades. More recently, new technological developments in membrane and sorbent manipulation have made it possible to deliver more biocompatible extracorporeal adsorption therapies to patients with a variety of conditions. There are several key rationales based on physicochemical principles and clinical considerations that justify the application and investigation of such therapies as evidenced by multiple ex-vivo, experimental, and clinical observations. Accordingly, unspecific adsorptive extracorporeal therapies have now been applied to the treatment of a wide array of conditions from poisoning to drug overdoses, to inflammatory states and sepsis, and acute or chronic liver and kidney failure. In response to the rapidly expanding knowledge base and increased clinical evidence, we convened an Acute Disease Quality Initiative (ADQI) consensus conference dedicated to such treatment. The data show that hemoadsorption has clinically acceptable short-term biocompatibility and safety, technical feasibility, and experimental demonstration of specified target molecule removal. Pilot studies demonstrate potentially beneficial effects on physiology and larger studies of endotoxin-based hemoadsorption have identified possible target phenotypes for larger randomized controlled trials (RCTs). Moreover, in a variety of endogenous and exogenous intoxications, removal of target molecules has been confirmed in vivo. However, some studies have raised concerns about harm or failed to deliver benefits. Thus, despite many achievements, modern hemoadsorption remains a novel and experimental intervention with limited data, and a large research agenda.

11.
J Hepatol ; 78(5): 1028-1036, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36702176

RESUMO

BACKGROUND & AIMS: Mouse models of lineage tracing have helped to describe the important subpopulations of hepatocytes responsible for liver regeneration. However, conflicting results have been obtained from different models. Herein, we aimed to reconcile these conflicting reports by repeating a key lineage-tracing study from pericentral hepatocytes and characterising this Axin2CreERT2 model in detail. METHODS: We performed detailed characterisation of the labelled population in the Axin2CreERT2 model. We lineage traced this cell population, quantifying the labelled population over 1 year and performed in-depth phenotypic comparisons, including transcriptomics, metabolomics and analysis of proteins through immunohistochemistry, of Axin2CreERT2 mice to WT counterparts. RESULTS: We found that after careful definition of a baseline population, there are marked differences in labelling between male and female mice. Upon induced lineage tracing there was no expansion of the labelled hepatocyte population in Axin2CreERT2 mice. We found substantial evidence of disrupted homeostasis in Axin2CreERT2 mice. Offspring are born with sub-Mendelian ratios and adult mice have perturbations of hepatic Wnt/ß-catenin signalling and related metabolomic disturbance. CONCLUSIONS: We find no evidence of predominant expansion of the pericentral hepatocyte population during liver homeostatic regeneration. Our data highlight the importance of detailed preclinical model characterisation and the pitfalls which may occur when comparing across sexes and backgrounds of mice and the effects of genetic insertion into native loci. IMPACT AND IMPLICATIONS: Understanding the source of cells which regenerate the liver is crucial to harness their potential to regrow injured livers. Herein, we show that cells which were previously thought to repopulate the liver play only a limited role in physiological regeneration. Our data helps to reconcile differing conclusions drawn from results from a number of prior studies and highlights methodological challenges which are relevant to preclinical models more generally.


Assuntos
Hiperplasia Nodular Focal do Fígado , Regeneração Hepática , Masculino , Feminino , Humanos , Regeneração Hepática/fisiologia , Hepatócitos/metabolismo , Fígado/metabolismo , Homeostase , Proliferação de Células , Proteína Axina/genética
12.
N Engl J Med ; 382(7): 622-631, 2020 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-32053298

RESUMO

BACKGROUND: More effective and safer treatments are needed for antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis. METHODS: We conducted a randomized trial with a 2-by-2 factorial design to evaluate the use of plasma exchange and two regimens of oral glucocorticoids in patients with severe ANCA-associated vasculitis (defined by an estimated glomerular filtration rate of <50 ml per minute per 1.73 m2 of body-surface area or diffuse pulmonary hemorrhage). Patients were randomly assigned to undergo plasma exchange (seven plasma exchanges within 14 days after randomization) or no plasma exchange (control group). Patients were also randomly assigned to follow either a standard-dose regimen or a reduced-dose regimen of oral glucocorticoids. Patients were followed for up to 7 years for the primary composite outcome of death from any cause or end-stage kidney disease (ESKD). RESULTS: Death from any cause or ESKD occurred in 100 of 352 patients (28.4%) in the plasma-exchange group and in 109 of 352 patients (31.0%) in the control group (hazard ratio, 0.86; 95% confidence interval [CI], 0.65 to 1.13; P = 0.27). The results were similar in subgroup analyses and in analyses of secondary outcomes. We also assessed the noninferiority of a reduced-dose regimen of glucocorticoids to a standard-dose regimen, using a noninferiority margin of 11 percentage points. Death from any cause or ESKD occurred in 92 of 330 patients (27.9%) in the reduced-dose group and in 83 of 325 patients (25.5%) in the standard-dose group (absolute risk difference, 2.3 percentage points; 90% CI, -3.4 to 8.0), which met the criterion for noninferiority. Serious infections at 1 year were less common in the reduced-dose group than in the standard-dose group (incidence rate ratio, 0.69; 95% CI, 0.52 to 0.93), but other secondary outcomes were similar in the two groups. CONCLUSIONS: Among patients with severe ANCA-associated vasculitis, the use of plasma exchange did not reduce the incidence of death or ESKD. A reduced-dose regimen of glucocorticoids was noninferior to a standard-dose regimen with respect to death or ESKD. (Funded by the U.K. National Institute for Health Research and others; PEXIVAS Current Controlled Trials number, ISRCTN07757494; ClinicalTrials.gov number, NCT00987389.).


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/tratamento farmacológico , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/terapia , Glucocorticoides/administração & dosagem , Falência Renal Crônica/prevenção & controle , Troca Plasmática , Administração Oral , Adulto , Idoso , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/complicações , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/mortalidade , Terapia Combinada , Ciclofosfamida/uso terapêutico , Relação Dose-Resposta a Droga , Feminino , Glucocorticoides/efeitos adversos , Humanos , Imunossupressores/uso terapêutico , Incidência , Quimioterapia de Indução , Nefropatias/complicações , Falência Renal Crônica/epidemiologia , Falência Renal Crônica/etiologia , Masculino , Pessoa de Meia-Idade , Troca Plasmática/efeitos adversos , Rituximab/uso terapêutico
13.
Chemistry ; 29(16): e202203955, 2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36722619

RESUMO

The compound Ge32 Co9-x (x=0.54(6), a=10.9861(3) Å, space group Im 3 ‾ $\bar 3$ m) prepared under high pressure and at high temperature is metastable under ambient conditions. It crystallizes in a new structure type, Pearson symbol cI82-1.08. The crystal structure represents a slightly distorted cubic primitive arrangement of germanium atoms with part of the Ge cubes filled by cobalt. Analysis of the chemical bonding by real-space methods revealed three-core cluster units Ge16 Co3 and seemingly empty regions comprising either covalent inter-polyhedral Ge-Ge bonds or lone-pairs located at the germanium atoms. The electrical conductivity is metal-like.

14.
Anim Cogn ; 26(1): 153-173, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36352174

RESUMO

Birds are excellent model organisms to study perceptual categorization and concept formation. The renewed focus on avian neuroscience has sparked an explosion of new data in the field. At the same time, our understanding of sensory and particularly visual structures in the avian brain has shifted fundamentally. These recent discoveries have revealed how categorization is mediated in the avian brain and has generated a theoretical framework that goes beyond the realm of birds. We review the contribution of avian categorization research-at the methodical, behavioral, and neurobiological levels. To this end, we first introduce avian categorization from a behavioral perspective and the common elements model of categorization. Second, we describe the functional and structural organization of the avian visual system, followed by an overview of recent anatomical discoveries and the new perspective on the avian 'visual cortex'. Third, we focus on the neurocomputational basis of perceptual categorization in the bird's visual system. Fourth, an overview of the avian prefrontal cortex and the prefrontal contribution to perceptual categorization is provided. The fifth section outlines how asymmetries of the visual system contribute to categorization. Finally, we present a mechanistic view of the neural principles of avian visual categorization and its putative extension to concept learning.


Assuntos
Aves , Encéfalo , Animais , Formação de Conceito
15.
Blood Purif ; : 1-14, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37703868

RESUMO

In order to develop a standardized nomenclature for the mechanisms and materials utilized during extracorporeal blood purification, a consensus expert conference was convened in November 2022. Standardized nomenclature serves as a common language for reporting research findings, new device development, and education. It is also critically important to support patient safety, allow comparisons between techniques, materials, and devices, and be essential for defining and naming innovative technologies and classifying devices for regulatory approval. The multidisciplinary conference developed detailed descriptions of the performance characteristics of devices (membranes, filters, and sorbents), solute and fluid transport mechanisms, flow parameters, and methods of treatment evaluation. In addition, nomenclature for adsorptive blood purification techniques was proposed. This report summarizes these activities and highlights the need for standardization of nomenclature in the future to harmonize research, education, and innovation in extracorporeal blood purification therapies.

16.
Sensors (Basel) ; 23(10)2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37430804

RESUMO

This paper will introduce a simple locating system to track a stent when it is deployed into a human artery. The stent is proposed to achieve hemostasis for bleeding soldiers on the battlefield, where common surgical imaging equipment such as fluoroscopy systems are not available. In the application of interest, the stent must be guided to the right location to avoid serious complications. The most important features are its relative accuracy and the ease by which it may be quickly set up and used in a trauma situation. The locating approach in this paper utilizes a magnet outside the human body as the reference and a magnetometer that will be deployed inside the artery with the stent. The sensor can detect its location in a coordinate system centered with the reference magnet. In practice, the main challenge is that the locating accuracy will be deteriorated by external magnetic interference, rotation of the sensor, and random noise. These causes of error are addressed in the paper to improve the locating accuracy and repeatability under various conditions. Finally, the system's locating performance will be validated in benchtop experiments, where the effects of the disturbance-eliminating procedures will be addressed.


Assuntos
Artérias , Corpo Humano , Humanos , Fluoroscopia , Stents , Acelerometria
17.
Gut ; 2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35477863

RESUMO

OBJECTIVE: Hepatocellular carcinoma (HCC) is increasingly associated with non-alcoholic steatohepatitis (NASH). HCC immunotherapy offers great promise; however, recent data suggests NASH-HCC may be less sensitive to conventional immune checkpoint inhibition (ICI). We hypothesised that targeting neutrophils using a CXCR2 small molecule inhibitor may sensitise NASH-HCC to ICI therapy. DESIGN: Neutrophil infiltration was characterised in human HCC and mouse models of HCC. Late-stage intervention with anti-PD1 and/or a CXCR2 inhibitor was performed in murine models of NASH-HCC. The tumour immune microenvironment was characterised by imaging mass cytometry, RNA-seq and flow cytometry. RESULTS: Neutrophils expressing CXCR2, a receptor crucial to neutrophil recruitment in acute-injury, are highly represented in human NASH-HCC. In models of NASH-HCC lacking response to ICI, the combination of a CXCR2 antagonist with anti-PD1 suppressed tumour burden and extended survival. Combination therapy increased intratumoural XCR1+ dendritic cell activation and CD8+ T cell numbers which are associated with anti-tumoural immunity, this was confirmed by loss of therapeutic effect on genetic impairment of myeloid cell recruitment, neutralisation of the XCR1-ligand XCL1 or depletion of CD8+ T cells. Therapeutic benefit was accompanied by an unexpected increase in tumour-associated neutrophils (TANs) which switched from a protumour to anti-tumour progenitor-like neutrophil phenotype. Reprogrammed TANs were found in direct contact with CD8+ T cells in clusters that were enriched for the cytotoxic anti-tumoural protease granzyme B. Neutrophil reprogramming was not observed in the circulation indicative of the combination therapy selectively influencing TANs. CONCLUSION: CXCR2-inhibition induces reprogramming of the tumour immune microenvironment that promotes ICI in NASH-HCC.

18.
Proc Natl Acad Sci U S A ; 116(34): 16799-16804, 2019 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-31371499

RESUMO

There is now recognition that a population's overall level of well-being is defined not just by income and wealth. Where we live and who we interact with are likely to be equally important in our overall levels of satisfaction with our lives. This thinking has stimulated studies of subjective well-being, or happiness, at both national and local scales. These studies suggest that where you live does matter, although it is health and family status that have the most direct effects on well-being. In this study, we use a detailed dataset on well-being from the China Household Finance Survey to reexamine well-being across China, where profound socioeconomic changes are taking place. The study controls for self-reported health and examines subjective well-being across extensive and varied Chinese urban and rural environments. We find that the earlier pessimism about China's well-being, which emphasized declining happiness, may be misplaced. We make two contributions: first, we show a rising level of subjective well-being, and second, we show that there is a narrowing gap in well-being across different social indicators. Methodologically, we bring in the perspectives of both social capital and geographic context.


Assuntos
Felicidade , Sociedades , China , Humanos , Satisfação Pessoal , Análise de Regressão
20.
Proc Natl Acad Sci U S A ; 116(25): 12250-12254, 2019 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-31147462

RESUMO

We introduce a mathematical framework that allows one to carry out multiscalar and multigroup spatial exploratory analysis across urban regions. By producing coefficients that integrate information across all scales and that are normalized with respect to theoretical maximally segregated configurations, this framework provides a practical and powerful tool for the comparative empirical analysis of urban segregation. We illustrate our method with a study of ethnic mixing in the Los Angeles metropolitan area.

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