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1.
Cell ; 179(3): 729-735.e10, 2019 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-31495572

RESUMO

We report an ancient genome from the Indus Valley Civilization (IVC). The individual we sequenced fits as a mixture of people related to ancient Iranians (the largest component) and Southeast Asian hunter-gatherers, a unique profile that matches ancient DNA from 11 genetic outliers from sites in Iran and Turkmenistan in cultural communication with the IVC. These individuals had little if any Steppe pastoralist-derived ancestry, showing that it was not ubiquitous in northwest South Asia during the IVC as it is today. The Iranian-related ancestry in the IVC derives from a lineage leading to early Iranian farmers, herders, and hunter-gatherers before their ancestors separated, contradicting the hypothesis that the shared ancestry between early Iranians and South Asians reflects a large-scale spread of western Iranian farmers east. Instead, sampled ancient genomes from the Iranian plateau and IVC descend from different groups of hunter-gatherers who began farming without being connected by substantial movement of people.


Assuntos
DNA Antigo/química , Genoma Humano , Migração Humana , Linhagem , População/genética , Povo Asiático/genética , Evolução Molecular , Humanos , Irã (Geográfico) , Paquistão
2.
Cell ; 164(1-2): 183-196, 2016 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-26771491

RESUMO

Proper establishment of synapses is critical for constructing functional circuits. Interactions between presynaptic neurexins and postsynaptic neuroligins coordinate the formation of synaptic adhesions. An isoform code determines the direct interactions of neurexins and neuroligins across the synapse. However, whether extracellular linker proteins can expand such a code is unknown. Using a combination of in vitro and in vivo approaches, we found that hevin, an astrocyte-secreted synaptogenic protein, assembles glutamatergic synapses by bridging neurexin-1alpha and neuroligin-1B, two isoforms that do not interact with each other. Bridging of neurexin-1alpha and neuroligin-1B via hevin is critical for the formation and plasticity of thalamocortical connections in the developing visual cortex. These results show that astrocytes promote the formation of synapses by modulating neurexin/neuroligin adhesions through hevin secretion. Our findings also provide an important mechanistic insight into how mutations in these genes may lead to circuit dysfunction in diseases such as autism.


Assuntos
Astrócitos/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Moléculas de Adesão Celular Neuronais/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Moléculas de Adesão de Célula Nervosa/metabolismo , Tálamo/metabolismo , Animais , Células COS , Chlorocebus aethiops , Dominância Ocular , Humanos , Camundongos , Camundongos Knockout , Doenças do Sistema Nervoso/metabolismo , Neurônios/metabolismo , Isoformas de Proteínas/metabolismo , Transdução de Sinais , Sinapses/metabolismo
3.
Nature ; 629(8013): 798-802, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38599238

RESUMO

Compared to polycrystalline semiconductors, amorphous semiconductors offer inherent cost-effective, simple and uniform manufacturing. Traditional amorphous hydrogenated Si falls short in electrical properties, necessitating the exploration of new materials. The creation of high-mobility amorphous n-type metal oxides, such as a-InGaZnO (ref. 1), and their integration into thin-film transistors (TFTs) have propelled advancements in modern large-area electronics and new-generation displays2-8. However, finding comparable p-type counterparts poses notable challenges, impeding the progress of complementary metal-oxide-semiconductor technology and integrated circuits9-11. Here we introduce a pioneering design strategy for amorphous p-type semiconductors, incorporating high-mobility tellurium within an amorphous tellurium suboxide matrix, and demonstrate its use in high-performance, stable p-channel TFTs and complementary circuits. Theoretical analysis unveils a delocalized valence band from tellurium 5p bands with shallow acceptor states, enabling excess hole doping and transport. Selenium alloying suppresses hole concentrations and facilitates the p-orbital connectivity, realizing high-performance p-channel TFTs with an average field-effect hole mobility of around 15 cm2 V-1 s-1 and on/off current ratios of 106-107, along with wafer-scale uniformity and long-term stabilities under bias stress and ambient ageing. This study represents a crucial stride towards establishing commercially viable amorphous p-channel TFT technology and complementary electronics in a low-cost and industry-compatible manner.

4.
Genes Dev ; 35(3-4): 286-299, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33446571

RESUMO

RNase E is an essential, multifunctional ribonuclease encoded in E. coli by the rne gene. Structural analysis indicates that the ribonucleolytic activity of this enzyme is conferred by rne-encoded polypeptide chains that (1) dimerize to form a catalytic site at the protein-protein interface, and (2) multimerize further to generate a tetrameric quaternary structure consisting of two dimerized Rne-peptide chains. We identify here a mutation in the Rne protein's catalytic region (E429G), as well as a bacterial cell wall peptidoglycan hydrolase (Amidase C [AmiC]), that selectively affect the specific activity of the RNase E enzyme on long RNA substrates, but not on short synthetic oligonucleotides, by enhancing enzyme multimerization. Unlike the increase in specific activity that accompanies concentration-induced multimerization, enhanced multimerization associated with either the E429G mutation or interaction of the Rne protein with AmiC is independent of the substrate's 5' terminus phosphorylation state. Our findings reveal a previously unsuspected substrate length-dependent regulatory role for RNase E quaternary structure and identify cis-acting and trans-acting factors that mediate such regulation.


Assuntos
Endorribonucleases/química , Endorribonucleases/metabolismo , Proteínas de Escherichia coli/química , Escherichia coli/enzimologia , Escherichia coli/genética , Modelos Moleculares , Amidoidrolases/metabolismo , Domínio Catalítico , Endorribonucleases/genética , Proteínas de Escherichia coli/genética , Mutação/genética , Estrutura Quaternária de Proteína , RNA Bacteriano/metabolismo , Regulação para Cima/genética
5.
Nat Immunol ; 17(11): 1252-1262, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27595231

RESUMO

The mammalian cytoplasmic multi-tRNA synthetase complex (MSC) is a depot system that regulates non-translational cellular functions. Here we found that the MSC component glutamyl-prolyl-tRNA synthetase (EPRS) switched its function following viral infection and exhibited potent antiviral activity. Infection-specific phosphorylation of EPRS at Ser990 induced its dissociation from the MSC, after which it was guided to the antiviral signaling pathway, where it interacted with PCBP2, a negative regulator of mitochondrial antiviral signaling protein (MAVS) that is critical for antiviral immunity. This interaction blocked PCBP2-mediated ubiquitination of MAVS and ultimately suppressed viral replication. EPRS-haploid (Eprs+/-) mice showed enhanced viremia and inflammation and delayed viral clearance. This stimulus-inducible activation of MAVS by EPRS suggests an unexpected role for the MSC as a regulator of immune responses to viral infection.


Assuntos
Aminoacil-tRNA Sintetases/metabolismo , Resistência à Doença/imunologia , Interações Hospedeiro-Patógeno/imunologia , Viroses/imunologia , Viroses/metabolismo , Aminoacil-tRNA Sintetases/química , Aminoacil-tRNA Sintetases/genética , Animais , Antivirais/farmacologia , Modelos Animais de Doenças , Imunidade Inata , Camundongos , Camundongos Knockout , Peptídeos/farmacologia , Fosforilação , Ligação Proteica , Infecções por Vírus de RNA/imunologia , Infecções por Vírus de RNA/metabolismo , Infecções por Vírus de RNA/virologia , Vírus de RNA/efeitos dos fármacos , Vírus de RNA/imunologia , Proteínas de Ligação a RNA/metabolismo , Transdução de Sinais , Ubiquitinação , Viroses/virologia , Replicação Viral
6.
Cell ; 152(4): 831-43, 2013 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-23415230

RESUMO

p11, through unknown mechanisms, is required for behavioral and cellular responses to selective serotonin reuptake inhibitors (SSRIs). We show that SMARCA3, a chromatin-remodeling factor, is a target for the p11/annexin A2 heterotetrameric complex. Determination of the crystal structure indicates that SMARCA3 peptide binds to a hydrophobic pocket in the heterotetramer. Formation of this complex increases the DNA-binding affinity of SMARCA3 and its localization to the nuclear matrix fraction. In the dentate gyrus, both p11 and SMARCA3 are highly enriched in hilar mossy cells and basket cells. The SSRI fluoxetine induces expression of p11 in both cell types and increases the amount of the ternary complex of p11/annexin A2/SMARCA3. SSRI-induced neurogenesis and behavioral responses are abolished by constitutive knockout of SMARCA3. Our studies indicate a central role for a chromatin-remodeling factor in the SSRI/p11 signaling pathway and suggest an approach to the development of improved antidepressant therapies. PAPERCLIP:


Assuntos
Anexina A2/metabolismo , Proteínas de Ligação a DNA/metabolismo , Giro Denteado/metabolismo , Proteínas S100/metabolismo , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Fatores de Transcrição/metabolismo , Sequência de Aminoácidos , Animais , Proteínas de Ligação a DNA/química , Feminino , Masculino , Modelos Moleculares , Dados de Sequência Molecular , Fibras Musgosas Hipocampais/metabolismo , Alinhamento de Sequência , Transdução de Sinais , Fatores de Transcrição/química , Difração de Raios X
7.
Nature ; 603(7901): 434-438, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35296844

RESUMO

Oxidation can deteriorate the properties of copper that are critical for its use, particularly in the semiconductor industry and electro-optics applications1-7. This has prompted numerous studies exploring copper oxidation and possible passivation strategies8. In situ observations have, for example, shown that oxidation involves stepped surfaces: Cu2O growth occurs on flat surfaces as a result of Cu adatoms detaching from steps and diffusing across terraces9-11. But even though this mechanism explains why single-crystalline copper is more resistant to oxidation than polycrystalline copper, the fact that flat copper surfaces can be free of oxidation has not been explored further. Here we report the fabrication of copper thin films that are semi-permanently oxidation resistant because they consist of flat surfaces with only occasional mono-atomic steps. First-principles calculations confirm that mono-atomic step edges are as impervious to oxygen as flat surfaces and that surface adsorption of O atoms is suppressed once an oxygen face-centred cubic (fcc) surface site coverage of 50% has been reached. These combined effects explain the exceptional oxidation resistance of ultraflat Cu surfaces.

8.
Proc Natl Acad Sci U S A ; 121(7): e2314346121, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38315837

RESUMO

Tobacco and alcohol are risk factors for human papillomavirus-negative head and neck squamous cell carcinoma (HPV- HNSCC), which arises from the mucosal epithelium of the upper aerodigestive tract. Notably, despite the mutagenic potential of smoking, HPV- HNSCC exhibits a low mutational load directly attributed to smoking, which implies an undefined role of smoking in HPV- HNSCC. Elevated YAP (Yes-associated protein) mRNA is prevalent in HPV- HNSCC, irrespective of the YAP gene amplification status, and the mechanism behind this upregulation remains elusive. Here, we report that oxidative stress, induced by major risk factors for HPV- HNSCC such as tobacco and alcohol, promotes YAP transcription via TM4SF19 (transmembrane 4 L six family member 19). TM4SF19 modulates YAP transcription by interacting with the GABP (Guanine and adenine-binding protein) transcription factor complex. Mechanistically, oxidative stress induces TM4SF19 dimerization and topology inversion in the endoplasmic reticulum membrane, which in turn protects the GABPß1 subunit from proteasomal degradation. Conversely, depletion of TM4SF19 impairs the survival, proliferation, and migration of HPV- HNSCC cells, highlighting the potential therapeutic relevance of targeting TM4SF19. Our findings reveal the roles of the key risk factors of HPV- HNSCC in tumor development via oxidative stress, offering implications for upcoming therapeutic approaches in HPV- HNSCC.


Assuntos
Neoplasias de Cabeça e Pescoço , Carcinoma de Células Escamosas de Cabeça e Pescoço , Humanos , Neoplasias de Cabeça e Pescoço/genética , Papillomaviridae , Infecções por Papillomavirus/patologia , Fatores de Risco , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética
9.
PLoS Genet ; 20(1): e1011054, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38236837

RESUMO

Living in dynamic environments such as the social domain, where interaction with others determines the reproductive success of individuals, requires the ability to recognize opportunities to obtain natural rewards and cope with challenges that are associated with achieving them. As such, actions that promote survival and reproduction are reinforced by the brain reward system, whereas coping with the challenges associated with obtaining these rewards is mediated by stress-response pathways, the activation of which can impair health and shorten lifespan. While much research has been devoted to understanding mechanisms underlying the way by which natural rewards are processed by the reward system, less attention has been given to the consequences of failure to obtain a desirable reward. As a model system to study the impact of failure to obtain a natural reward, we used the well-established courtship suppression paradigm in Drosophila melanogaster as means to induce repeated failures to obtain sexual reward in male flies. We discovered that beyond the known reduction in courtship actions caused by interaction with non-receptive females, repeated failures to mate induce a stress response characterized by persistent motivation to obtain the sexual reward, reduced male-male social interaction, and enhanced aggression. This frustrative-like state caused by the conflict between high motivation to obtain sexual reward and the inability to fulfill their mating drive impairs the capacity of rejected males to tolerate stressors such as starvation and oxidative stress. We further show that sensitivity to starvation and enhanced social arousal is mediated by the disinhibition of a small population of neurons that express receptors for the fly homologue of neuropeptide Y. Our findings demonstrate for the first time the existence of social stress in flies and offers a framework to study mechanisms underlying the crosstalk between reward, stress, and reproduction in a simple nervous system that is highly amenable to genetic manipulation.


Assuntos
Drosophila melanogaster , Neuropeptídeos , Comportamento Sexual Animal , Humanos , Animais , Feminino , Masculino , Drosophila melanogaster/genética , Comportamento Sexual Animal/fisiologia , Reprodução/genética , Recompensa , Neurônios/metabolismo
10.
Proc Natl Acad Sci U S A ; 121(12): e2310866121, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38483996

RESUMO

Lymphocyte activation gene-3 (LAG-3) is an inhibitory receptor expressed on activated T cells and an emerging immunotherapy target. Domain 1 (D1) of LAG-3, which has been purported to directly interact with major histocompatibility complex class II (MHCII) and fibrinogen-like protein 1 (FGL1), has been the major focus for the development of therapeutic antibodies that inhibit LAG-3 receptor-ligand interactions and restore T cell function. Here, we present a high-resolution structure of glycosylated mouse LAG-3 ectodomain, identifying that cis-homodimerization, mediated through a network of hydrophobic residues within domain 2 (D2), is critically required for LAG-3 function. Additionally, we found a previously unidentified key protein-glycan interaction in the dimer interface that affects the spatial orientation of the neighboring D1 domain. Mutation of LAG-3 D2 residues reduced dimer formation, dramatically abolished LAG-3 binding to both MHCII and FGL1 ligands, and consequentially inhibited the role of LAG-3 in suppressing T cell responses. Intriguingly, we showed that antibodies directed against D1, D2, and D3 domains are all capable of blocking LAG-3 dimer formation and MHCII and FGL-1 ligand binding, suggesting a potential allosteric model of LAG-3 function tightly regulated by dimerization. Furthermore, our work reveals unique epitopes, in addition to D1, that can be targeted for immunotherapy of cancer and other human diseases.


Assuntos
Antígenos de Histocompatibilidade Classe II , Linfócitos T , Animais , Humanos , Camundongos , Dimerização , Fibrinogênio/metabolismo , Ligantes , Mutação
11.
Nature ; 586(7831): 735-740, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32879487

RESUMO

Innate immunity is associated with Alzheimer's disease1, but the influence of immune activation on the production of amyloid-ß is unknown2,3. Here we identify interferon-induced transmembrane protein 3 (IFITM3) as a γ-secretase modulatory protein, and establish a mechanism by which inflammation affects the generation of amyloid-ß. Inflammatory cytokines induce the expression of IFITM3 in neurons and astrocytes, which binds to γ-secretase and upregulates its activity, thereby increasing the production of amyloid-ß. The expression of IFITM3 is increased with ageing and in mouse models that express familial Alzheimer's disease genes. Furthermore, knockout of IFITM3 reduces γ-secretase activity and the formation of amyloid plaques in a transgenic mouse model (5xFAD) of early amyloid deposition. IFITM3 protein is upregulated in tissue samples from a subset of patients with late-onset Alzheimer's disease that exhibit higher γ-secretase activity. The amount of IFITM3 in the γ-secretase complex has a strong and positive correlation with γ-secretase activity in samples from patients with late-onset Alzheimer's disease. These findings reveal a mechanism in which γ-secretase is modulated by neuroinflammation via IFITM3 and the risk of Alzheimer's disease is thereby increased.


Assuntos
Doença de Alzheimer/imunologia , Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Imunidade Inata , Proteínas de Membrana/metabolismo , Proteínas de Ligação a RNA/metabolismo , Idade de Início , Idoso de 80 Anos ou mais , Envelhecimento/genética , Envelhecimento/imunologia , Envelhecimento/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Secretases da Proteína Precursora do Amiloide/química , Precursor de Proteína beta-Amiloide/química , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Astrócitos/metabolismo , Domínio Catalítico , Modelos Animais de Doenças , Feminino , Células HEK293 , Humanos , Inflamação , Masculino , Proteínas de Membrana/deficiência , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Presenilina-1/metabolismo , Proteínas de Ligação a RNA/genética , Risco , Regulação para Cima
12.
Nucleic Acids Res ; 52(11): e50, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38797520

RESUMO

Whole-genome bisulfite sequencing (BS-Seq) measures cytosine methylation changes at single-base resolution and can be used to profile cell-free DNA (cfDNA). In plasma, ultrashort single-stranded cfDNA (uscfDNA, ∼50 nt) has been identified together with 167 bp double-stranded mononucleosomal cell-free DNA (mncfDNA). However, the methylation profile of uscfDNA has not been described. Conventional BS-Seq workflows may not be helpful because bisulfite conversion degrades larger DNA into smaller fragments, leading to erroneous categorization as uscfDNA. We describe the '5mCAdpBS-Seq' workflow in which pre-methylated 5mC (5-methylcytosine) single-stranded adapters are ligated to heat-denatured cfDNA before bisulfite conversion. This method retains only DNA fragments that are unaltered by bisulfite treatment, resulting in less biased uscfDNA methylation analysis. Using 5mCAdpBS-Seq, uscfDNA had lower levels of DNA methylation (∼15%) compared to mncfDNA and was enriched in promoters and CpG islands. Hypomethylated uscfDNA fragments were enriched in upstream transcription start sites (TSSs), and the intensity of enrichment was correlated with expressed genes of hemopoietic cells. Using tissue-of-origin deconvolution, we inferred that uscfDNA is derived primarily from eosinophils, neutrophils, and monocytes. As proof-of-principle, we show that characteristics of the methylation profile of uscfDNA can distinguish non-small cell lung carcinoma from non-cancer samples. The 5mCAdpBS-Seq workflow is recommended for any cfDNA methylation-based investigations.


Assuntos
5-Metilcitosina , Ácidos Nucleicos Livres , Ilhas de CpG , Metilação de DNA , DNA de Cadeia Simples , Humanos , Ácidos Nucleicos Livres/sangue , Ácidos Nucleicos Livres/genética , DNA de Cadeia Simples/metabolismo , DNA de Cadeia Simples/genética , DNA de Cadeia Simples/sangue , 5-Metilcitosina/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/sangue , Sulfitos/química , Regiões Promotoras Genéticas , Análise de Sequência de DNA/métodos , Sequenciamento Completo do Genoma/métodos
13.
Proc Natl Acad Sci U S A ; 120(2): e2215509119, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36608295

RESUMO

Recently, Co-based honeycomb magnets have been proposed as promising candidate materials to host the Kitaev spin liquid (KSL) state. One of the front-runners is BaCo2(AsO4)2 (BCAO), where it was suggested that the exchange processes between Co2+ ions via the surrounding edge-sharing oxygen octahedra could give rise to bond-dependent Kitaev interactions. In this work, we present and analyze a comprehensive inelastic neutron scattering (INS) study of BCAO with fields in the honeycomb plane. Combining the constraints from the magnon excitations in the high-field polarized state and the inelastic spin structure factor measured in zero magnetic field, we examine two leading theoretical models: the Kitaev-type [Formula: see text] model and the XXZ[Formula: see text]model. We show that the existing experimental data can be consistently accounted for by the XXZ[Formula: see text]model but not by the [Formula: see text] model, and we discuss the implications of these results for the realization of a spin liquid phase in BCAO and more generally for the realization of the Kitaev model in cobaltates.

14.
N Engl J Med ; 386(5): 437-448, 2022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-35045221

RESUMO

BACKGROUND: Standard therapy for advanced endometrial cancer after failure of platinum-based chemotherapy remains unclear. METHODS: In this phase 3 trial, we randomly assigned, in a 1:1 ratio, patients with advanced endometrial cancer who had previously received at least one platinum-based chemotherapy regimen to receive either lenvatinib (20 mg, administered orally once daily) plus pembrolizumab (200 mg, administered intravenously every 3 weeks) or chemotherapy of the treating physician's choice (doxorubicin at 60 mg per square meter of body-surface area, administered intravenously every 3 weeks, or paclitaxel at 80 mg per square meter, administered intravenously weekly [with a cycle of 3 weeks on and 1 week off]). The two primary end points were progression-free survival as assessed on blinded independent central review according to the Response Evaluation Criteria in Solid Tumors, version 1.1, and overall survival. The end points were evaluated in patients with mismatch repair-proficient (pMMR) disease and in all patients. Safety was also assessed. RESULTS: A total of 827 patients (697 with pMMR disease and 130 with mismatch repair-deficient disease) were randomly assigned to receive lenvatinib plus pembrolizumab (411 patients) or chemotherapy (416 patients). The median progression-free survival was longer with lenvatinib plus pembrolizumab than with chemotherapy (pMMR population: 6.6 vs. 3.8 months; hazard ratio for progression or death, 0.60; 95% confidence interval [CI], 0.50 to 0.72; P<0.001; overall: 7.2 vs. 3.8 months; hazard ratio, 0.56; 95% CI, 0.47 to 0.66; P<0.001). The median overall survival was longer with lenvatinib plus pembrolizumab than with chemotherapy (pMMR population: 17.4 vs. 12.0 months; hazard ratio for death, 0.68; 95% CI, 0.56 to 0.84; P<0.001; overall: 18.3 vs. 11.4 months; hazard ratio, 0.62; 95% CI, 0.51 to 0.75; P<0.001). Adverse events of grade 3 or higher occurred in 88.9% of the patients who received lenvatinib plus pembrolizumab and in 72.7% of those who received chemotherapy. CONCLUSIONS: Lenvatinib plus pembrolizumab led to significantly longer progression-free survival and overall survival than chemotherapy among patients with advanced endometrial cancer. (Funded by Eisai and Merck Sharp and Dohme [a subsidiary of Merck]; Study 309-KEYNOTE-775 ClinicalTrials.gov number, NCT03517449.).


Assuntos
Anticorpos Monoclonais Humanizados/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Endométrio/tratamento farmacológico , Compostos de Fenilureia/administração & dosagem , Quinolinas/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias do Endométrio/mortalidade , Feminino , Humanos , Pessoa de Meia-Idade , Compostos de Fenilureia/efeitos adversos , Quinolinas/efeitos adversos , Análise de Sobrevida
15.
N Engl J Med ; 386(6): 544-555, 2022 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-35139273

RESUMO

BACKGROUND: Patients with recurrent cervical cancer have a poor prognosis. Cemiplimab, the fully human programmed cell death 1 (PD-1)-blocking antibody approved to treat lung and skin cancers, has been shown to have preliminary clinical activity in this population. METHODS: In this phase 3 trial, we enrolled patients who had disease progression after first-line platinum-containing chemotherapy, regardless of their programmed cell death ligand 1 (PD-L1) status. Women were randomly assigned (1:1) to receive cemiplimab (350 mg every 3 weeks) or the investigator's choice of single-agent chemotherapy. The primary end point was overall survival. Progression-free survival and safety were also assessed. RESULTS: A total of 608 women were enrolled (304 in each group). In the overall trial population, median overall survival was longer in the cemiplimab group than in the chemotherapy group (12.0 months vs. 8.5 months; hazard ratio for death, 0.69; 95% confidence interval [CI], 0.56 to 0.84; two-sided P<0.001). The overall survival benefit was consistent in both histologic subgroups (squamous-cell carcinoma and adenocarcinoma [including adenosquamous carcinoma]). Progression-free survival was also longer in the cemiplimab group than in the chemotherapy group in the overall population (hazard ratio for disease progression or death, 0.75; 95% CI, 0.63 to 0.89; two-sided P<0.001). In the overall population, an objective response occurred in 16.4% (95% CI, 12.5 to 21.1) of the patients in the cemiplimab group, as compared with 6.3% (95% CI, 3.8 to 9.6) in the chemotherapy group. An objective response occurred in 18% (95% CI, 11 to 28) of the cemiplimab-treated patients with PD-L1 expression greater than or equal to 1% and in 11% (95% CI, 4 to 25) of those with PD-L1 expression of less than 1%. Overall, grade 3 or higher adverse events occurred in 45.0% of the patients who received cemiplimab and in 53.4% of those who received chemotherapy. CONCLUSIONS: Survival was significantly longer with cemiplimab than with single-agent chemotherapy among patients with recurrent cervical cancer after first-line platinum-containing chemotherapy. (Funded by Regeneron Pharmaceuticals and Sanofi; EMPOWER-Cervical 1/GOG-3016/ENGOT-cx9 ClinicalTrials.gov number, NCT03257267.).


Assuntos
Adenocarcinoma/tratamento farmacológico , Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos Imunológicos/uso terapêutico , Carcinoma Adenoescamoso/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Neoplasias do Colo do Útero/tratamento farmacológico , Adenocarcinoma/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/efeitos adversos , Antineoplásicos Imunológicos/efeitos adversos , Biomarcadores Tumorais/metabolismo , Carcinoma Adenoescamoso/mortalidade , Progressão da Doença , Feminino , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/mortalidade , Receptor de Morte Celular Programada 1/metabolismo , Qualidade de Vida , Análise de Sobrevida , Neoplasias do Colo do Útero/mortalidade
16.
Ann Neurol ; 95(5): 876-885, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38400785

RESUMO

OBJECTIVES: To investigate whether post-stroke statin therapy reduces subsequent major vascular events in statin-naïve patients with pretreatment low-density lipoprotein cholesterol (LDL-C) below the recommended target (≤70 mg/dL for atherosclerotic stroke and ≤100 mg/dL for non-atherosclerotic stroke) at stroke onset. METHODS: Patients from an ongoing stroke registry who had an ischemic stroke between 2011 and 2020 were screened. Statin naïve patients with baseline LDL-C below the target were assessed. The effect of post-stroke statin therapy on major vascular events (composite of recurrent stroke, myocardial infarction, and death) was investigated using weighted Cox regression analyses using stabilized inverse probability treatment weighting. RESULTS: The baseline LDL-C level of the 1,858 patients (mean age 67.9 ± 15.3 years, 61.4% men, 13.2% atherosclerotic stroke) included in the study was 75.7 ± 17.0 mg/dL. Statins were prescribed to 1,256 (67.7%) patients (low-to-moderate intensity, 23.5%; high intensity, 44.1%). Post-stroke statin therapy was associated with a lower risk of major vascular events during 1-year follow-up (weighted hazard ratio 0.55, 95% confidence interval 0.42-0.71). In a subgroup of patients who were at very high risk of atherosclerotic cardiovascular disease with LDL-C <55 mg/dL or patients who were not at very high risk of atherosclerotic cardiovascular disease with LDL-C <70 mg/dL, post-stroke statin therapy was also associated with a reduction in major vascular events (weighted hazard ratio 0.45, 95% confidence interval 0.29-0.70). The intensity of the most beneficial statin varied by subtype of stroke. INTERPRETATION: Statin therapy may improve vascular outcomes after ischemic stroke, even in cases of LDL-C below the target without pre-stroke lipid-lowering therapy. ANN NEUROL 2024;95:876-885.


Assuntos
LDL-Colesterol , Inibidores de Hidroximetilglutaril-CoA Redutases , Acidente Vascular Cerebral , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Masculino , Feminino , Idoso , LDL-Colesterol/sangue , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/tratamento farmacológico , Sistema de Registros , Resultado do Tratamento , AVC Isquêmico/tratamento farmacológico , AVC Isquêmico/sangue , Doenças Cardiovasculares/tratamento farmacológico
17.
FASEB J ; 38(2): e23407, 2024 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-38197598

RESUMO

This study investigated the role of the axis involving chemokine receptor 6 (CCR6) and its ligand chemokine (C-C motif) ligand 20 (CCL20) in acute kidney disease (AKD) using an ischemia-reperfusion injury (IRI) model. The model was established by clamping the unilateral renal artery pedicle of C57BL/6 mice for 30 min, followed by evaluation of CCL20/CCR6 expression at 4 weeks post-IRI. In vitro studies were conducted to examine the effects of hypoxia and H2 O2 -induced oxidative stress on CCL20/CCR6 expression in kidney tissues of patients with AKD and chronic kidney disease (CKD). Tubular epithelial cell apoptosis was more severe in C57BL/6 mice than in CCL20 antibody-treated mice, and CCR6, NGAL mRNA, and IL-8 levels were higher under hypoxic conditions. CCL20 blockade ameliorated apoptotic damage in a dose-dependent manner under hypoxia and reactive oxygen species injury. CCR6 expression in IRI mice indicated that the disease severity was similar to that in patients with the AKD phenotype. Morphometry of CCL20/CCR6 expression revealed a higher likelihood of CCR6+ cell presence in CKD stage 3 patients than in stage 1-2 patients. Kidney tissues of patients with CKD frequently contained CCL20+ cells, which were positively correlated with interstitial inflammation. CCL20/CCR6 levels were increased in fibrotic kidneys at 4 and 8 weeks after 5/6 nephrectomy. These findings suggest that modulating the CCL20/CCR6 pathway is a potential therapeutic strategy for managing the progression of AKD to CKD.


Assuntos
Injúria Renal Aguda , Insuficiência Renal Crônica , Humanos , Animais , Camundongos , Camundongos Endogâmicos C57BL , Ligantes , Rim , Células Epiteliais , Artéria Renal , Hipóxia , Receptores CCR6/genética , Quimiocina CCL20/genética
18.
Mol Psychiatry ; 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38704508

RESUMO

Sensory abnormalities are observed in ~90% of individuals with autism spectrum disorders (ASD), but the underlying mechanisms are poorly understood. GluN2B, an NMDA receptor subunit that regulates long-term depression and circuit refinement during brain development, has been strongly implicated in ASD, but whether GRIN2B mutations lead to sensory abnormalities remains unclear. Here, we report that Grin2b-mutant mice show behavioral sensory hypersensitivity and brain hyperconnectivity associated with the anterior cingulate cortex (ACC). Grin2b-mutant mice with a patient-derived C456Y mutation (Grin2bC456Y/+) show sensory hypersensitivity to mechanical, thermal, and electrical stimuli through supraspinal mechanisms. c-fos and functional magnetic resonance imaging indicate that the ACC is hyperactive and hyperconnected with other brain regions under baseline and stimulation conditions. ACC pyramidal neurons show increased excitatory synaptic transmission. Chemogenetic inhibition of ACC pyramidal neurons normalizes ACC hyperconnectivity and sensory hypersensitivity. These results suggest that GluN2B critically regulates ASD-related cortical connectivity and sensory brain functions.

19.
Circ Res ; 132(1): 52-71, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36448450

RESUMO

BACKGROUND: The osteochondrogenic switch of vascular smooth muscle cells (VSMCs) is a pivotal cellular process in atherosclerotic calcification. However, the exact molecular mechanism of the osteochondrogenic transition of VSMCs remains to be elucidated. Here, we explore the regulatory role of TXNIP (thioredoxin-interacting protein) in the phenotypical transitioning of VSMCs toward osteochondrogenic cells responsible for atherosclerotic calcification. METHODS: The atherosclerotic phenotypes of Txnip-/- mice were analyzed in combination with single-cell RNA-sequencing. The atherosclerotic phenotypes of Tagln-Cre; Txnipflox/flox mice (smooth muscle cell-specific Txnip ablation model), and the mice transplanted with the bone marrow of Txnip-/- mice were analyzed. Public single-cell RNA-sequencing dataset (GSE159677) was reanalyzed to define the gene expression of TXNIP in human calcified atherosclerotic plaques. The effect of TXNIP suppression on the osteochondrogenic phenotypic changes in primary aortic VSMCs was analyzed. RESULTS: Atherosclerotic lesions of Txnip-/- mice presented significantly increased calcification and deposition of collagen content. Subsequent single-cell RNA-sequencing analysis identified the modulated VSMC and osteochondrogenic clusters, which were VSMC-derived populations. The osteochondrogenic cluster was markedly expanded in Txnip-/- mice. The pathway analysis of the VSMC-derived cells revealed enrichment of bone- and cartilage-formation-related pathways and bone morphogenetic protein signaling in Txnip-/- mice. Reanalyzing public single-cell RNA-sequencing dataset revealed that TXNIP was downregulated in the modulated VSMC and osteochondrogenic clusters of human calcified atherosclerotic lesions. Tagln-Cre; Txnipflox/flox mice recapitulated the calcification and collagen-rich atherosclerotic phenotypes of Txnip-/- mice, whereas the hematopoietic deficiency of TXNIP did not affect the lesion phenotype. Suppression of TXNIP in cultured VSMCs accelerates osteodifferentiation and upregulates bone morphogenetic protein signaling. Treatment with the bone morphogenetic protein signaling inhibitor K02288 abrogated the effect of TXNIP suppression on osteodifferentiation. CONCLUSIONS: Our results suggest that TXNIP is a novel regulator of atherosclerotic calcification by suppressing bone morphogenetic protein signaling to inhibit the transition of VSMCs toward an osteochondrogenic phenotype.


Assuntos
Aterosclerose , Calcinose , Placa Aterosclerótica , Calcificação Vascular , Camundongos , Humanos , Animais , Músculo Liso Vascular/metabolismo , Células Cultivadas , Aterosclerose/metabolismo , Placa Aterosclerótica/patologia , Calcinose/metabolismo , Proteínas Morfogenéticas Ósseas/metabolismo , Miócitos de Músculo Liso/metabolismo , RNA/metabolismo , Calcificação Vascular/genética , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Tiorredoxinas/metabolismo
20.
Cell ; 140(4): 529-39, 2010 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-20178745

RESUMO

A circadian clock coordinates physiology and behavior in diverse groups of living organisms. Another major cyclic cellular event, the cell cycle, is regulated by the circadian clock in the few cases where linkage of these cycles has been studied. In the cyanobacterium Synechococcus elongatus, the circadian clock gates cell division by an unknown mechanism. Using timelapse microscopy, we confirm the gating of cell division in the wild-type and demonstrate the regulation of cytokinesis by key clock components. Specifically, a state of the oscillator protein KaiC that is associated with elevated ATPase activity closes the gate by acting through a known clock output pathway to inhibit FtsZ ring formation at the division site. An activity that stimulates KaiC phosphorylation independently of the KaiA protein was also uncovered. We propose a model that separates the functions of KaiC ATPase and phosphorylation in cell division gating and other circadian behaviors.


Assuntos
Proteínas de Bactérias/metabolismo , Divisão Celular , Peptídeos e Proteínas de Sinalização do Ritmo Circadiano/metabolismo , Ritmo Circadiano , Synechococcus/citologia , Synechococcus/fisiologia , Relógios Biológicos , Proteínas do Citoesqueleto/metabolismo , Regulação Bacteriana da Expressão Gênica , Fosforilação , Proteínas Quinases/metabolismo
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