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1.
Cell ; 180(5): 833-846.e16, 2020 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-32142677

RESUMO

Cognitive dysfunction and reactive microglia are hallmarks of traumatic brain injury (TBI), yet whether these cells contribute to cognitive deficits and secondary inflammatory pathology remains poorly understood. Here, we show that removal of microglia from the mouse brain has little effect on the outcome of TBI, but inducing the turnover of these cells through either pharmacologic or genetic approaches can yield a neuroprotective microglial phenotype that profoundly aids recovery. The beneficial effects of these repopulating microglia are critically dependent on interleukin-6 (IL-6) trans-signaling via the soluble IL-6 receptor (IL-6R) and robustly support adult neurogenesis, specifically by augmenting the survival of newborn neurons that directly support cognitive function. We conclude that microglia in the mammalian brain can be manipulated to adopt a neuroprotective and pro-regenerative phenotype that can aid repair and alleviate the cognitive deficits arising from brain injury.


Assuntos
Lesões Encefálicas Traumáticas/terapia , Interleucina-6/genética , Receptores de Interleucina-6/genética , Regeneração/genética , Animais , Encéfalo/crescimento & desenvolvimento , Encéfalo/patologia , Lesões Encefálicas Traumáticas/genética , Lesões Encefálicas Traumáticas/patologia , Disfunção Cognitiva/genética , Disfunção Cognitiva/patologia , Disfunção Cognitiva/terapia , Modelos Animais de Doenças , Humanos , Inflamação/genética , Inflamação/patologia , Camundongos , Microglia/metabolismo , Microglia/patologia , Neurônios/metabolismo , Neurônios/patologia , Fármacos Neuroprotetores/uso terapêutico , Transdução de Sinais/genética
2.
CA Cancer J Clin ; 73(5): 516-523, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37114458

RESUMO

The American Joint Committee on Cancer (AJCC) staging system for all cancer sites, including anal cancer, is the standard for cancer staging in the United States. The AJCC staging criteria are dynamic, and periodic updates are conducted to optimize AJCC staging definitions through a panel of experts charged with evaluating new evidence to implement changes. With greater availability of large data sets, the AJCC has since restructured and updated its processes, incorporating prospectively collected data to validate stage group revisions in the version 9 AJCC staging system, including anal cancer. Survival analysis using AJCC eighth edition staging guidelines revealed a lack of hierarchical order in which stage IIIA anal cancer was associated with a better prognosis than stage IIB disease, suggesting that, for anal cancer, tumor (T) category has a greater effect on survival than lymph node (N) category. Accordingly, version 9 stage groups have been appropriately adjusted to reflect contemporary long-term outcomes. This article highlights the changes to the now published AJCC staging system for anal cancer, which: (1) redefined stage IIB as T1-T2N1M0 disease, (2) redefined stage IIIA as T3N0-N1M0 disease, and (3) eliminated stage 0 disease from its guidelines altogether.


Assuntos
Neoplasias do Ânus , Humanos , Estados Unidos , Estadiamento de Neoplasias , Prognóstico , Análise de Sobrevida , Neoplasias do Ânus/diagnóstico
3.
Nat Immunol ; 17(4): 406-13, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26950237

RESUMO

The acute phase of sepsis is characterized by a strong inflammatory reaction. At later stages in some patients, immunoparalysis may be encountered, which is associated with a poor outcome. By transcriptional and metabolic profiling of human patients with sepsis, we found that a shift from oxidative phosphorylation to aerobic glycolysis was an important component of initial activation of host defense. Blocking metabolic pathways with metformin diminished cytokine production and increased mortality in systemic fungal infection in mice. In contrast, in leukocytes rendered tolerant by exposure to lipopolysaccharide or after isolation from patients with sepsis and immunoparalysis, a generalized metabolic defect at the level of both glycolysis and oxidative metabolism was apparent, which was restored after recovery of the patients. Finally, the immunometabolic defects in humans were partially restored by therapy with recombinant interferon-γ, which suggested that metabolic processes might represent a therapeutic target in sepsis.


Assuntos
Citocinas/imunologia , Endotoxemia/imunologia , Metabolismo Energético/imunologia , Tolerância Imunológica/imunologia , Imunidade Inata/imunologia , Macrófagos/imunologia , Monócitos/imunologia , Sepse/imunologia , Trifosfato de Adenosina/metabolismo , Adulto , Animais , Antifúngicos/uso terapêutico , Aspergilose/tratamento farmacológico , Aspergilose/imunologia , Aspergilose/metabolismo , Candidíase Invasiva/tratamento farmacológico , Candidíase Invasiva/imunologia , Candidíase Invasiva/metabolismo , Endotoxemia/metabolismo , Infecções por Escherichia coli/imunologia , Infecções por Escherichia coli/metabolismo , Feminino , Glicólise , Humanos , Immunoblotting , Interferon gama/uso terapêutico , Ácido Láctico/metabolismo , Leucócitos/imunologia , Leucócitos/metabolismo , Lipopolissacarídeos/imunologia , Macrófagos/metabolismo , Masculino , Camundongos , Pessoa de Meia-Idade , Monócitos/metabolismo , NAD/metabolismo , Fosforilação Oxidativa , Consumo de Oxigênio , Estudos Prospectivos , Sepse/tratamento farmacológico , Sepse/metabolismo , Transcriptoma , Adulto Jovem
4.
Nature ; 612(7941): 778-786, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36517593

RESUMO

High-grade serous ovarian cancer (HGSOC) is an archetypal cancer of genomic instability1-4 patterned by distinct mutational processes5,6, tumour heterogeneity7-9 and intraperitoneal spread7,8,10. Immunotherapies have had limited efficacy in HGSOC11-13, highlighting an unmet need to assess how mutational processes and the anatomical sites of tumour foci determine the immunological states of the tumour microenvironment. Here we carried out an integrative analysis of whole-genome sequencing, single-cell RNA sequencing, digital histopathology and multiplexed immunofluorescence of 160 tumour sites from 42 treatment-naive patients with HGSOC. Homologous recombination-deficient HRD-Dup (BRCA1 mutant-like) and HRD-Del (BRCA2 mutant-like) tumours harboured inflammatory signalling and ongoing immunoediting, reflected in loss of HLA diversity and tumour infiltration with highly differentiated dysfunctional CD8+ T cells. By contrast, foldback-inversion-bearing tumours exhibited elevated immunosuppressive TGFß signalling and immune exclusion, with predominantly naive/stem-like and memory T cells. Phenotypic state associations were specific to anatomical sites, highlighting compositional, topological and functional differences between adnexal tumours and distal peritoneal foci. Our findings implicate anatomical sites and mutational processes as determinants of evolutionary phenotypic divergence and immune resistance mechanisms in HGSOC. Our study provides a multi-omic cellular phenotype data substrate from which to develop and interpret future personalized immunotherapeutic approaches and early detection research.


Assuntos
Evasão da Resposta Imune , Mutação , Neoplasias Ovarianas , Feminino , Humanos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Cistadenocarcinoma Seroso/genética , Cistadenocarcinoma Seroso/imunologia , Cistadenocarcinoma Seroso/patologia , Recombinação Homóloga , Evasão da Resposta Imune/genética , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/imunologia , Neoplasias Ovarianas/patologia , Microambiente Tumoral , Fator de Crescimento Transformador beta , Genes BRCA1 , Genes BRCA2
5.
Nature ; 612(7938): 106-115, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36289342

RESUMO

How cell-to-cell copy number alterations that underpin genomic instability1 in human cancers drive genomic and phenotypic variation, and consequently the evolution of cancer2, remains understudied. Here, by applying scaled single-cell whole-genome sequencing3 to wild-type, TP53-deficient and TP53-deficient;BRCA1-deficient or TP53-deficient;BRCA2-deficient mammary epithelial cells (13,818 genomes), and to primary triple-negative breast cancer (TNBC) and high-grade serous ovarian cancer (HGSC) cells (22,057 genomes), we identify three distinct 'foreground' mutational patterns that are defined by cell-to-cell structural variation. Cell- and clone-specific high-level amplifications, parallel haplotype-specific copy number alterations and copy number segment length variation (serrate structural variations) had measurable phenotypic and evolutionary consequences. In TNBC and HGSC, clone-specific high-level amplifications in known oncogenes were highly prevalent in tumours bearing fold-back inversions, relative to tumours with homologous recombination deficiency, and were associated with increased clone-to-clone phenotypic variation. Parallel haplotype-specific alterations were also commonly observed, leading to phylogenetic evolutionary diversity and clone-specific mono-allelic expression. Serrate variants were increased in tumours with fold-back inversions and were highly correlated with increased genomic diversity of cellular populations. Together, our findings show that cell-to-cell structural variation contributes to the origins of phenotypic and evolutionary diversity in TNBC and HGSC, and provide insight into the genomic and mutational states of individual cancer cells.


Assuntos
Genômica , Mutação , Neoplasias Ovarianas , Análise de Célula Única , Neoplasias de Mama Triplo Negativas , Feminino , Humanos , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Filogenia , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia
6.
Nature ; 591(7850): 482-487, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33503651

RESUMO

Naturally occurring protein switches have been repurposed for the development of biosensors and reporters for cellular and clinical applications1. However, the number of such switches is limited, and reengineering them is challenging. Here we show that a general class of protein-based biosensors can be created by inverting the flow of information through de novo designed protein switches in which the binding of a peptide key triggers biological outputs of interest2. The designed sensors are modular molecular devices with a closed dark state and an open luminescent state; analyte binding drives the switch from the closed to the open state. Because the sensor is based on the thermodynamic coupling of analyte binding to sensor activation, only one target binding domain is required, which simplifies sensor design and allows direct readout in solution. We create biosensors that can sensitively detect the anti-apoptosis protein BCL-2, the IgG1 Fc domain, the HER2 receptor, and Botulinum neurotoxin B, as well as biosensors for cardiac troponin I and an anti-hepatitis B virus antibody with the high sensitivity required to detect these molecules clinically. Given the need for diagnostic tools to track the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)3, we used the approach to design sensors for the SARS-CoV-2 spike protein and antibodies against the membrane and nucleocapsid proteins. The former, which incorporates a de novo designed spike receptor binding domain (RBD) binder4, has a limit of detection of 15 pM and a luminescence signal 50-fold higher than the background level. The modularity and sensitivity of the platform should enable the rapid construction of sensors for a wide range of analytes, and highlights the power of de novo protein design to create multi-state protein systems with new and useful functions.


Assuntos
Anticorpos Antivirais/análise , Técnicas Biossensoriais/métodos , Vírus da Hepatite B/imunologia , SARS-CoV-2/química , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/análise , Troponina I/análise , Anticorpos Antivirais/imunologia , Técnicas Biossensoriais/normas , Toxinas Botulínicas/análise , Proteínas do Nucleocapsídeo de Coronavírus/imunologia , Imunoglobulina G/análise , Imunoglobulina G/imunologia , Limite de Detecção , Luminescência , Fosfoproteínas/imunologia , Proteínas Proto-Oncogênicas c-bcl-2/análise , Receptor ErbB-2/análise , Sensibilidade e Especificidade , Proteínas da Matriz Viral/imunologia
7.
Nature ; 595(7868): 585-590, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34163070

RESUMO

Progress in defining genomic fitness landscapes in cancer, especially those defined by copy number alterations (CNAs), has been impeded by lack of time-series single-cell sampling of polyclonal populations and temporal statistical models1-7. Here we generated 42,000 genomes from multi-year time-series single-cell whole-genome sequencing of breast epithelium and primary triple-negative breast cancer (TNBC) patient-derived xenografts (PDXs), revealing the nature of CNA-defined clonal fitness dynamics induced by TP53 mutation and cisplatin chemotherapy. Using a new Wright-Fisher population genetics model8,9 to infer clonal fitness, we found that TP53 mutation alters the fitness landscape, reproducibly distributing fitness over a larger number of clones associated with distinct CNAs. Furthermore, in TNBC PDX models with mutated TP53, inferred fitness coefficients from CNA-based genotypes accurately forecast experimentally enforced clonal competition dynamics. Drug treatment in three long-term serially passaged TNBC PDXs resulted in cisplatin-resistant clones emerging from low-fitness phylogenetic lineages in the untreated setting. Conversely, high-fitness clones from treatment-naive controls were eradicated, signalling an inversion of the fitness landscape. Finally, upon release of drug, selection pressure dynamics were reversed, indicating a fitness cost of treatment resistance. Together, our findings define clonal fitness linked to both CNA and therapeutic resistance in polyclonal tumours.


Assuntos
Variações do Número de Cópias de DNA , Resistencia a Medicamentos Antineoplásicos , Neoplasias de Mama Triplo Negativas/genética , Animais , Linhagem Celular Tumoral , Cisplatino/farmacologia , Células Clonais/patologia , Feminino , Aptidão Genética , Humanos , Camundongos , Modelos Estatísticos , Transplante de Neoplasias , Proteína Supressora de Tumor p53/genética , Sequenciamento Completo do Genoma
8.
Proc Natl Acad Sci U S A ; 121(33): e2405454121, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39106310

RESUMO

Regeneration of hyaline cartilage in human-sized joints remains a clinical challenge, and it is a critical unmet need that would contribute to longer healthspans. Injectable scaffolds for cartilage repair that integrate both bioactivity and sufficiently robust physical properties to withstand joint stresses offer a promising strategy. We report here on a hybrid biomaterial that combines a bioactive peptide amphiphile supramolecular polymer that specifically binds the chondrogenic cytokine transforming growth factor ß-1 (TGFß-1) and crosslinked hyaluronic acid microgels that drive formation of filament bundles, a hierarchical motif common in natural musculoskeletal tissues. The scaffold is an injectable slurry that generates a porous rubbery material when exposed to calcium ions once placed in cartilage defects. The hybrid material was found to support in vitro chondrogenic differentiation of encapsulated stem cells in response to sustained delivery of TGFß-1. Using a sheep model, we implanted the scaffold in shallow osteochondral defects and found it can remain localized in mechanically active joints. Evaluation of resected joints showed significantly improved repair of hyaline cartilage in osteochondral defects injected with the scaffold relative to defects injected with the growth factor alone, including implantation in the load-bearing femoral condyle. These results demonstrate the potential of the hybrid biomimetic scaffold as a niche to favor cartilage repair in mechanically active joints using a clinically relevant large-animal model.


Assuntos
Condrogênese , Alicerces Teciduais , Fator de Crescimento Transformador beta1 , Animais , Alicerces Teciduais/química , Ovinos , Fator de Crescimento Transformador beta1/metabolismo , Condrogênese/efeitos dos fármacos , Polímeros/química , Ácido Hialurônico/química , Ácido Hialurônico/farmacologia , Cartilagem Articular/efeitos dos fármacos , Regeneração/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Engenharia Tecidual/métodos , Humanos , Materiais Biocompatíveis/química , Condrócitos/efeitos dos fármacos , Cartilagem Hialina/metabolismo
9.
N Engl J Med ; 389(4): 322-334, 2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37272534

RESUMO

BACKGROUND: Pelvic radiation plus sensitizing chemotherapy with a fluoropyrimidine (chemoradiotherapy) before surgery is standard care for locally advanced rectal cancer in North America. Whether neoadjuvant chemotherapy with fluorouracil, leucovorin, and oxaliplatin (FOLFOX) can be used in lieu of chemoradiotherapy is uncertain. METHODS: We conducted a multicenter, unblinded, noninferiority, randomized trial of neoadjuvant FOLFOX (with chemoradiotherapy given only if the primary tumor decreased in size by <20% or if FOLFOX was discontinued because of side effects) as compared with chemoradiotherapy. Adults with rectal cancer that had been clinically staged as T2 node-positive, T3 node-negative, or T3 node-positive who were candidates for sphincter-sparing surgery were eligible to participate. The primary end point was disease-free survival. Noninferiority would be claimed if the upper limit of the two-sided 90.2% confidence interval of the hazard ratio for disease recurrence or death did not exceed 1.29. Secondary end points included overall survival, local recurrence (in a time-to-event analysis), complete pathological resection, complete response, and toxic effects. RESULTS: From June 2012 through December 2018, a total of 1194 patients underwent randomization and 1128 started treatment; among those who started treatment, 585 were in the FOLFOX group and 543 in the chemoradiotherapy group. At a median follow-up of 58 months, FOLFOX was noninferior to chemoradiotherapy for disease-free survival (hazard ratio for disease recurrence or death, 0.92; 90.2% confidence interval [CI], 0.74 to 1.14; P = 0.005 for noninferiority). Five-year disease-free survival was 80.8% (95% CI, 77.9 to 83.7) in the FOLFOX group and 78.6% (95% CI, 75.4 to 81.8) in the chemoradiotherapy group. The groups were similar with respect to overall survival (hazard ratio for death, 1.04; 95% CI, 0.74 to 1.44) and local recurrence (hazard ratio, 1.18; 95% CI, 0.44 to 3.16). In the FOLFOX group, 53 patients (9.1%) received preoperative chemoradiotherapy and 8 (1.4%) received postoperative chemoradiotherapy. CONCLUSIONS: In patients with locally advanced rectal cancer who were eligible for sphincter-sparing surgery, preoperative FOLFOX was noninferior to preoperative chemoradiotherapy with respect to disease-free survival. (Funded by the National Cancer Institute; PROSPECT ClinicalTrials.gov number, NCT01515787.).


Assuntos
Neoplasias Retais , Adulto , Humanos , Canal Anal/cirurgia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimiorradioterapia/efeitos adversos , Quimiorradioterapia/métodos , Quimioterapia Adjuvante , Intervalo Livre de Doença , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Leucovorina/administração & dosagem , Leucovorina/efeitos adversos , Terapia Neoadjuvante , Recidiva Local de Neoplasia/tratamento farmacológico , Estadiamento de Neoplasias , Tratamentos com Preservação do Órgão , Oxaliplatina/administração & dosagem , Oxaliplatina/efeitos adversos , Neoplasias Retais/mortalidade , Neoplasias Retais/patologia , Neoplasias Retais/cirurgia , Cuidados Pré-Operatórios , Período Pré-Operatório
10.
Blood ; 143(10): 912-929, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38048572

RESUMO

ABSTRACT: Chronic graft-versus-host disease (cGVHD) remains a significant complication of allogeneic hematopoietic stem cell transplantation. Central nervous system (CNS) involvement is becoming increasingly recognized, in which brain-infiltrating donor major histocompatibility complex (MHC) class II+ bone marrow-derived macrophages (BMDM) drive pathology. BMDM are also mediators of cutaneous and pulmonary cGVHD, and clinical trials assessing the efficacy of antibody blockade of colony-stimulating factor 1 receptor (CSF1R) to deplete macrophages are promising. We hypothesized that CSF1R antibody blockade may also be a useful strategy to prevent/treat CNS cGVHD. Increased blood-brain barrier permeability during acute GVHD (aGVHD) facilitated CNS antibody access and microglia depletion by anti-CSF1R treatment. However, CSF1R blockade early after transplant unexpectedly exacerbated aGVHD neuroinflammation. In established cGVHD, vascular changes and anti-CSF1R efficacy were more limited. Anti-CSF1R-treated mice retained donor BMDM, activated microglia, CD8+ and CD4+ T cells, and local cytokine expression in the brain. These findings were recapitulated in GVHD recipients, in which CSF1R was conditionally depleted in donor CX3CR1+ BMDM. Notably, inhibition of CSF1R signaling after transplant failed to reverse GVHD-induced behavioral changes. Moreover, we observed aberrant behavior in non-GVHD control recipients administered anti-CSF1R blocking antibody and naïve mice lacking CSF1R in CX3CR1+ cells, revealing a novel role for homeostatic microglia and indicating that ongoing clinical trials of CSF1R inhibition should assess neurological adverse events in patients. In contrast, transfer of Ifngr-/- grafts could reduce MHC class II+ BMDM infiltration, resulting in improved neurocognitive function. Our findings highlight unexpected neurological immune toxicity during CSF1R blockade and provide alternative targets for the treatment of cGVHD within the CNS.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Humanos , Camundongos , Animais , Doenças Neuroinflamatórias , Doença Enxerto-Hospedeiro/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Linfócitos T CD4-Positivos , Macrófagos/patologia , Receptores Proteína Tirosina Quinases , Receptores de Fator Estimulador de Colônias
11.
Nature ; 580(7803): 413-417, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32296173

RESUMO

Intracellular replication of the deadly pathogen Mycobacterium tuberculosis relies on the production of small organic molecules called siderophores that scavenge iron from host proteins1. M. tuberculosis produces two classes of siderophore, lipid-bound mycobactin and water-soluble carboxymycobactin2,3. Functional studies have revealed that iron-loaded carboxymycobactin is imported into the cytoplasm by the ATP binding cassette (ABC) transporter IrtAB4, which features an additional cytoplasmic siderophore interaction domain5. However, the predicted ABC exporter fold of IrtAB is seemingly contradictory to its import function. Here we show that membrane-reconstituted IrtAB is sufficient to import mycobactins, which are then reduced by the siderophore interaction domain to facilitate iron release. Structure determination by X-ray crystallography and cryo-electron microscopy not only confirms that IrtAB has an ABC exporter fold, but also reveals structural peculiarities at the transmembrane region of IrtAB that result in a partially collapsed inward-facing substrate-binding cavity. The siderophore interaction domain is positioned in close proximity to the inner membrane leaflet, enabling the reduction of membrane-inserted mycobactin. Enzymatic ATPase activity and in vivo growth assays show that IrtAB has a preference for mycobactin over carboxymycobactin as its substrate. Our study provides insights into an unusual ABC exporter that evolved as highly specialized siderophore-import machinery in mycobacteria.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Proteínas de Bactérias/metabolismo , Mycobacterium smegmatis/metabolismo , Sideróforos/metabolismo , Transportadores de Cassetes de Ligação de ATP/química , Transportadores de Cassetes de Ligação de ATP/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Microscopia Crioeletrônica , Cristalografia por Raios X , Modelos Moleculares , Mycobacterium smegmatis/química , Mycobacterium smegmatis/genética , Estrutura Quaternária de Proteína , Estrutura Terciária de Proteína
12.
Proc Natl Acad Sci U S A ; 120(21): e2214327120, 2023 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-37186822

RESUMO

Delusions of control in schizophrenia are characterized by the striking feeling that one's actions are controlled by external forces. We here tested qualitative predictions inspired by Bayesian causal inference models, which suggest that such misattributions of agency should lead to decreased intentional binding. Intentional binding refers to the phenomenon that subjects perceive a compression of time between their intentional actions and consequent sensory events. We demonstrate that patients with delusions of control perceived less self-agency in our intentional binding task. This effect was accompanied by significant reductions of intentional binding as compared to healthy controls and patients without delusions. Furthermore, the strength of delusions of control tightly correlated with decreases in intentional binding. Our study validated a critical prediction of Bayesian accounts of intentional binding, namely that a pathological reduction of the prior likelihood of a causal relation between one's actions and consequent sensory events-here captured by delusions of control-should lead to lesser intentional binding. Moreover, our study highlights the import of an intact perception of temporal contiguity between actions and their effects for the sense of agency.


Assuntos
Esquizofrenia , Percepção do Tempo , Humanos , Desempenho Psicomotor , Teorema de Bayes , Emoções , Intenção , Percepção
13.
Proc Natl Acad Sci U S A ; 120(46): e2306129120, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37939083

RESUMO

Controlling the biodistribution of protein- and nanoparticle-based therapeutic formulations remains challenging. In vivo library selection is an effective method for identifying constructs that exhibit desired distribution behavior; library variants can be selected based on their ability to localize to the tissue or compartment of interest despite complex physiological challenges. Here, we describe further development of an in vivo library selection platform based on self-assembling protein nanoparticles encapsulating their own mRNA genomes (synthetic nucleocapsids or synNCs). We tested two distinct libraries: a low-diversity library composed of synNC surface mutations (45 variants) and a high-diversity library composed of synNCs displaying miniproteins with binder-like properties (6.2 million variants). While we did not identify any variants from the low-diversity surface library that yielded therapeutically relevant changes in biodistribution, the high-diversity miniprotein display library yielded variants that shifted accumulation toward lungs or muscles in just two rounds of in vivo selection. Our approach should contribute to achieving specific tissue homing patterns and identifying targeting ligands for diseases of interest.


Assuntos
Biblioteca de Peptídeos , Proteínas , Distribuição Tecidual , Nucleocapsídeo , Mutação
14.
Proc Natl Acad Sci U S A ; 120(23): e2220678120, 2023 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-37252966

RESUMO

Global change has converted many structurally complex and ecologically and economically valuable coastlines to bare substrate. In the structural habitats that remain, climate-tolerant and opportunistic species are increasing in response to environmental extremes and variability. The shifting of dominant foundation species identity with climate change poses a unique conservation challenge because species vary in their responses to environmental stressors and to management. Here, we combine 35 y of watershed modeling and biogeochemical water quality data with species comprehensive aerial surveys to describe causes and consequences of turnover in seagrass foundation species across 26,000 ha of habitat in the Chesapeake Bay. Repeated marine heatwaves have caused 54% retraction of the formerly dominant eelgrass (Zostera marina) since 1991, allowing 171% expansion of the temperature-tolerant widgeongrass (Ruppia maritima) that has likewise benefited from large-scale nutrient reductions. However, this phase shift in dominant seagrass identity now presents two significant shifts for management: Widgeongrass meadows are not only responsible for rapid, extensive recoveries but also for the largest crashes over the last four decades; and, while adapted to high temperatures, are much more susceptible than eelgrass to nutrient pulses driven by springtime runoff. Thus, by selecting for rapid post-disturbance recolonization but low resistance to punctuated freshwater flow disturbance, climate change could threaten the Chesapeake Bay seagrass' ability to provide consistent fishery habitat and sustain functioning over time. We demonstrate that understanding the dynamics of the next generation of foundation species is a critical management priority, because shifts from relatively stable habitat to high interannual variability can have far-reaching consequences across marine and terrestrial ecosystems.


Assuntos
Alismatales , Zosteraceae , Alismatales/fisiologia , Ecossistema , Mudança Climática , Baías
15.
Circulation ; 149(9): 669-683, 2024 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-38152968

RESUMO

BACKGROUND: Genetic and experimental studies support a causal involvement of IL-6 (interleukin-6) signaling in atheroprogression. Although trials targeting IL-6 signaling are underway, any benefits must be balanced against an impaired host immune response. Dissecting the mechanisms that mediate the effects of IL-6 signaling on atherosclerosis could offer insights about novel drug targets with more specific effects. METHODS: Leveraging data from 522 681 individuals, we constructed a genetic instrument of 26 variants in the gene encoding the IL-6R (IL-6 receptor) that proxied for pharmacological IL-6R inhibition. Using Mendelian randomization, we assessed its effects on 3281 plasma proteins quantified with an aptamer-based assay in the INTERVAL cohort (n=3301). Using mediation Mendelian randomization, we explored proteomic mediators of the effects of genetically proxied IL-6 signaling on coronary artery disease, large artery atherosclerotic stroke, and peripheral artery disease. For significant mediators, we tested associations of their circulating levels with incident cardiovascular events in a population-based study (n=1704) and explored the histological, transcriptomic, and cellular phenotypes correlated with their expression levels in samples from human atherosclerotic lesions. RESULTS: We found significant effects of genetically proxied IL-6 signaling on 70 circulating proteins involved in cytokine production/regulation and immune cell recruitment/differentiation, which correlated with the proteomic effects of pharmacological IL-6R inhibition in a clinical trial. Among the 70 significant proteins, genetically proxied circulating levels of CXCL10 (C-X-C motif chemokine ligand 10) were associated with risk of coronary artery disease, large artery atherosclerotic stroke, and peripheral artery disease, with up to 67% of the effects of genetically downregulated IL-6 signaling on these end points mediated by decreases in CXCL10. Higher midlife circulating CXCL10 levels were associated with a larger number of cardiovascular events over 20 years, whereas higher CXCL10 expression in human atherosclerotic lesions correlated with a larger lipid core and a transcriptomic profile reflecting immune cell infiltration, adaptive immune system activation, and cytokine signaling. CONCLUSIONS: Integrating multiomics data, we found a proteomic signature of IL-6 signaling activation and mediators of its effects on cardiovascular disease. Our analyses suggest the interferon-γ-inducible chemokine CXCL10 to be a potentially causal mediator for atherosclerosis in 3 vascular compartments and, as such, could serve as a promising drug target for atheroprotection.


Assuntos
Aterosclerose , Quimiocina CXCL10 , Interleucina-6 , Proteogenômica , Humanos , Aterosclerose/genética , Quimiocina CXCL10/metabolismo , Doença da Artéria Coronariana/genética , Estudo de Associação Genômica Ampla , Interleucina-6/metabolismo , Análise da Randomização Mendeliana , Doença Arterial Periférica , Proteômica , Acidente Vascular Cerebral/genética
16.
PLoS Comput Biol ; 20(1): e1011832, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38285727

RESUMO

Household studies provide an efficient means to study transmission of infectious diseases, enabling estimation of susceptibility and infectivity by person-type. A main inclusion criterion in such studies is usually the presence of an infected person. This precludes estimation of the hazards of pathogen introduction into the household. Here we estimate age- and time-dependent household introduction hazards together with within household transmission rates using data from a prospective household-based study in the Netherlands. A total of 307 households containing 1,209 persons were included from August 2020 until March 2021. Follow-up of households took place between August 2020 and August 2021 with maximal follow-up per household mostly limited to 161 days. Almost 1 out of 5 households (59/307) had evidence of an introduction of SARS-CoV-2. We estimate introduction hazards and within-household transmission rates in our study population with penalized splines and stochastic epidemic models, respectively. The estimated hazard of introduction of SARS-CoV-2 in the households was lower for children (0-12 years) than for adults (relative hazard: 0.62; 95%CrI: 0.34-1.0). Estimated introduction hazards peaked in mid October 2020, mid December 2020, and mid April 2021, preceding peaks in hospital admissions by 1-2 weeks. Best fitting transmission models included increased infectivity of children relative to adults and adolescents, such that the estimated child-to-child transmission probability (0.62; 95%CrI: 0.40-0.81) was considerably higher than the adult-to-adult transmission probability (0.12; 95%CrI: 0.057-0.19). Scenario analyses indicate that vaccination of adults can strongly reduce household infection attack rates and that adding adolescent vaccination offers limited added benefit.


Assuntos
COVID-19 , Epidemias , Adulto , Adolescente , Humanos , SARS-CoV-2 , Estudos Prospectivos , COVID-19/epidemiologia , Características da Família
17.
Nature ; 572(7768): 205-210, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31341284

RESUMO

Allosteric regulation of protein function is widespread in biology, but is challenging for de novo protein design as it requires the explicit design of multiple states with comparable free energies. Here we explore the possibility of designing switchable protein systems de novo, through the modulation of competing inter- and intramolecular interactions. We design a static, five-helix 'cage' with a single interface that can interact either intramolecularly with a terminal 'latch' helix or intermolecularly with a peptide 'key'. Encoded on the latch are functional motifs for binding, degradation or nuclear export that function only when the key displaces the latch from the cage. We describe orthogonal cage-key systems that function in vitro, in yeast and in mammalian cells with up to 40-fold activation of function by key. The ability to design switchable protein functions that are controlled by induced conformational change is a milestone for de novo protein design, and opens up new avenues for synthetic biology and cell engineering.


Assuntos
Regulação Alostérica , Engenharia de Proteínas/métodos , Proteínas/química , Proteínas/síntese química , Proteína 11 Semelhante a Bcl-2/metabolismo , Núcleo Celular/metabolismo , Sobrevivência Celular , Escherichia coli/genética , Escherichia coli/metabolismo , Regulação da Expressão Gênica , Células HEK293 , Humanos , Ligação Proteica , Transporte Proteico , Proteínas/metabolismo , Proteólise , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Biologia Sintética
18.
Am J Respir Crit Care Med ; 209(8): 973-986, 2024 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-38240721

RESUMO

Rationale: The plasma lipidome has the potential to reflect many facets of the host status during severe infection. Previous work is limited to specific lipid groups or was focused on lipids as prognosticators.Objectives: To map the plasma lipidome during sepsis due to community-acquired pneumonia (CAP) and determine the disease specificity and associations with clinical features.Methods: We analyzed 1,833 lipid species across 33 classes in 169 patients admitted to the ICU with sepsis due to CAP, 51 noninfected ICU patients, and 48 outpatient controls. In a paired analysis, we reanalyzed patients still in the ICU 4 days after admission (n = 82).Measurements and Main Results: A total of 58% of plasma lipids were significantly lower in patients with CAP-attributable sepsis compared with outpatient controls (6% higher, 36% not different). We found strong lipid class-specific associations with disease severity, validated across two external cohorts, and inflammatory biomarkers, in which triacylglycerols, cholesterol esters, and lysophospholipids exhibited the strongest associations. A total of 36% of lipids increased over time, and stratification by survival revealed diverging lipid recovery, which was confirmed in an external cohort; specifically, a 10% increase in cholesterol ester levels was related to a lower odds ratio (0.84; P = 0.006) for 30-day mortality (absolute mortality, 18 of 82). Comparison with noninfected ICU patients delineated a substantial common illness response (57.5%) and a distinct lipidomic signal for patients with CAP-attributable sepsis (37%).Conclusions: Patients with sepsis due to CAP exhibit a time-dependent and partially disease-specific shift in their plasma lipidome that correlates with disease severity and systemic inflammation and is associated with higher mortality.


Assuntos
Infecções Comunitárias Adquiridas , Pneumonia , Sepse , Humanos , Lipidômica , Pneumonia/complicações , Sepse/complicações , Lipídeos , Índice de Gravidade de Doença , Unidades de Terapia Intensiva
19.
Clin Infect Dis ; 78(4): 846-854, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38157401

RESUMO

INTRODUCTION: Recommended duration of antibiotic treatment of Staphylococcus aureus bacteremia (SAB) is frequently based on distinguishing uncomplicated and complicated SAB, and several risk factors at the onset of infection have been proposed to define complicated SAB. Predictive values of risk factors for complicated SAB have not been validated, and consequences of their use on antibiotic prescriptions are unknown. METHODS: In a prospective cohort, patients with SAB were categorized as complicated or uncomplicated through adjudication (reference definition). Associations and predictive values of 9 risk factors were determined, compared with the reference definition, as was accuracy of Infectious Diseases Society of America (IDSA) criteria that include 4 risk factors, and the projected consequences of applying IDSA criteria on antibiotic use. RESULTS: Among 490 patients, 296 (60%) had complicated SAB. In multivariable analysis, persistent bacteremia (odds ratio [OR], 6.8; 95% confidence interval [CI], 3.9-12.0), community acquisition of SAB (OR, 2.9; 95% CI, 1.9-4.7) and presence of prosthetic material (OR, 2.3; 95% CI, 1.5-3.6) were associated with complicated SAB. Presence of any of the 4 risk factors in the IDSA definition of complicated SAB had a positive predictive value of 70.9% (95% CI, 65.5-75.9) and a negative predictive value of 57.5% (95% CI, 49.1-64.8). Compared with the reference, IDSA criteria yielded 24 (5%) false-negative and 90 (18%) false-positive classifications of complicated SAB. Median duration of antibiotic treatment of these 90 patients was 16 days (interquartile range, 14-19), all with favorable clinical outcome. CONCLUSIONS: Risk factors have low to moderate predictive value to identify complicated SAB and their use may lead to unnecessary prolonged antibiotic use.


Assuntos
Bacteriemia , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Humanos , Resistência a Meticilina , Staphylococcus aureus , Estudos Prospectivos , Prevalência , Bacteriemia/tratamento farmacológico , Bacteriemia/epidemiologia , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/epidemiologia , Fatores de Risco , Antibacterianos/uso terapêutico , Antibacterianos/farmacologia
20.
Int J Cancer ; 154(12): 2054-2063, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38346920

RESUMO

Coffee consumption has been associated with a reduced risk of developing colorectal cancer (CRC). However, it is not clear whether coffee consumption is related to CRC progression. Hence, we assessed the association of coffee consumption with CRC recurrence and all-cause mortality using data from a prospective cohort study of 1719 stage I-III CRC patients in the Netherlands. Coffee consumption and other lifestyle characteristics were self-reported using questionnaires at the time of diagnosis. We retrieved recurrence and all-cause mortality data from the Netherlands Cancer Registry and the Personal Records Database, respectively. Cox proportional hazard regression models with and without restricted cubic splines were used to calculate hazard ratios (HR) and 95% confidence intervals (CI) adjusted for age, sex, education, smoking status, cancer stage and tumor location. We observed 257 recurrences during a 6.2-year median follow-up and 309 deaths during a 6.6-year median follow-up. Consuming more than 4 cups/d of coffee compared to an intake of <2 cups/d was associated with a 32% lower risk of CRC recurrence (95% CI: 0.49, 0.94,). The association between coffee consumption and all-cause mortality was U-shaped; coffee intake seemed optimal at 3-5 cups/d with the lowest risk at 4 cups/d (HR: 0.68, 95% CI: 0.53, 0.88). Our results suggest that coffee consumption may be associated with a lower risk of CRC recurrence and all-cause mortality. The association between coffee consumption and all-cause mortality appeared nonlinear. More studies are needed to understand the mechanism by which coffee consumption might improve CRC prognosis.


Assuntos
Café , Neoplasias Colorretais , Humanos , Fatores de Risco , Estudos Prospectivos , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/prevenção & controle , Causas de Morte , Inquéritos e Questionários
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