Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 7.230
Filtrar
Mais filtros

Intervalo de ano de publicação
1.
Nat Immunol ; 25(6): 1020-1032, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38831106

RESUMO

The efficacy of T cell-based immunotherapies is limited by immunosuppressive pressures in the tumor microenvironment. Here we show a predominant role for the interaction between BTLA on effector T cells and HVEM (TNFRSF14) on immunosuppressive tumor microenvironment cells, namely regulatory T cells. High BTLA expression in chimeric antigen receptor (CAR) T cells correlated with poor clinical response to treatment. Therefore, we deleted BTLA in CAR T cells and show improved tumor control and persistence in models of lymphoma and solid malignancies. Mechanistically, BTLA inhibits CAR T cells via recruitment of tyrosine phosphatases SHP-1 and SHP-2, upon trans engagement with HVEM. BTLA knockout thus promotes CAR signaling and subsequently enhances effector function. Overall, these data indicate that the BTLA-HVEM axis is a crucial immune checkpoint in CAR T cell immunotherapy and warrants the use of strategies to overcome this barrier.


Assuntos
Imunoterapia Adotiva , Receptores de Antígenos Quiméricos , Receptores Imunológicos , Membro 14 de Receptores do Fator de Necrose Tumoral , Microambiente Tumoral , Animais , Humanos , Imunoterapia Adotiva/métodos , Membro 14 de Receptores do Fator de Necrose Tumoral/metabolismo , Membro 14 de Receptores do Fator de Necrose Tumoral/imunologia , Membro 14 de Receptores do Fator de Necrose Tumoral/genética , Camundongos , Microambiente Tumoral/imunologia , Receptores de Antígenos Quiméricos/imunologia , Receptores de Antígenos Quiméricos/metabolismo , Receptores de Antígenos Quiméricos/genética , Receptores Imunológicos/metabolismo , Receptores Imunológicos/genética , Linfócitos T Reguladores/imunologia , Transdução de Sinais , Linhagem Celular Tumoral , Neoplasias/imunologia , Neoplasias/terapia , Camundongos Knockout
2.
Nat Immunol ; 24(9): 1443-1457, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37563309

RESUMO

Tissue-resident macrophages (TRMs) are long-lived cells that maintain locally and can be phenotypically distinct from monocyte-derived macrophages. Whether TRMs and monocyte-derived macrophages have district roles under differing pathologies is not understood. Here, we showed that a substantial portion of the macrophages that accumulated during pancreatitis and pancreatic cancer in mice had expanded from TRMs. Pancreas TRMs had an extracellular matrix remodeling phenotype that was important for maintaining tissue homeostasis during inflammation. Loss of TRMs led to exacerbation of severe pancreatitis and death, due to impaired acinar cell survival and recovery. During pancreatitis, TRMs elicited protective effects by triggering the accumulation and activation of fibroblasts, which was necessary for initiating fibrosis as a wound healing response. The same TRM-driven fibrosis, however, drove pancreas cancer pathogenesis and progression. Together, these findings indicate that TRMs play divergent roles in the pathogenesis of pancreatitis and cancer through regulation of stromagenesis.


Assuntos
Pâncreas , Pancreatite , Camundongos , Animais , Pâncreas/patologia , Macrófagos , Pancreatite/genética , Pancreatite/patologia , Fibrose , Neoplasias Pancreáticas
3.
Cell ; 176(4): 897-912.e20, 2019 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-30686579

RESUMO

A complete chart of cis-regulatory elements and their dynamic activity is necessary to understand the transcriptional basis of differentiation and function of an organ system. We generated matched epigenome and transcriptome measurements in 86 primary cell types that span the mouse immune system and its differentiation cascades. This breadth of data enable variance components analysis that suggests that genes fall into two distinct classes, controlled by either enhancer- or promoter-driven logic, and multiple regression that connects genes to the enhancers that regulate them. Relating transcription factor (TF) expression to the genome-wide accessibility of their binding motifs classifies them as predominantly openers or closers of local chromatin accessibility, pinpointing specific cis-regulatory elements where binding of given TFs is likely functionally relevant, validated by chromatin immunoprecipitation sequencing (ChIP-seq). Overall, this cis-regulatory atlas provides a trove of information on transcriptional regulation through immune differentiation and a foundational scaffold to define key regulatory events throughout the immunological genome.


Assuntos
Sistema Imunitário/imunologia , Sistema Imunitário/metabolismo , Elementos Reguladores de Transcrição/genética , Animais , Sítios de Ligação/genética , Cromatina , Imunoprecipitação da Cromatina/métodos , Elementos Facilitadores Genéticos/genética , Epigenômica/métodos , Regulação da Expressão Gênica/genética , Camundongos , Camundongos Endogâmicos C57BL , Regiões Promotoras Genéticas/genética , Ligação Proteica/genética , Fatores de Transcrição/metabolismo , Transcriptoma/genética
4.
Nat Immunol ; 21(10): 1194-1204, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32895539

RESUMO

Early atherosclerosis depends upon responses by immune cells resident in the intimal aortic wall. Specifically, the healthy intima is thought to be populated by vascular dendritic cells (DCs) that, during hypercholesterolemia, initiate atherosclerosis by being the first to accumulate cholesterol. Whether these cells remain key players in later stages of disease is unknown. Using murine lineage-tracing models and gene expression profiling, we reveal that myeloid cells present in the intima of the aortic arch are not DCs but instead specialized aortic intima resident macrophages (MacAIR) that depend upon colony-stimulating factor 1 and are sustained by local proliferation. Although MacAIR comprise the earliest foam cells in plaques, their proliferation during plaque progression is limited. After months of hypercholesterolemia, their presence in plaques is overtaken by recruited monocytes, which induce MacAIR-defining genes. These data redefine the lineage of intimal phagocytes and suggest that proliferation is insufficient to sustain generations of macrophages during plaque progression.


Assuntos
Aorta/imunologia , Macrófagos/imunologia , Monócitos/imunologia , Placa Aterosclerótica/imunologia , Túnica Íntima/imunologia , Animais , Diferenciação Celular , Linhagem da Célula , Movimento Celular , Proliferação de Células , Células Cultivadas , Colesterol/metabolismo , Progressão da Doença , Humanos , Fator Estimulador de Colônias de Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Parabiose , Fagocitose
5.
Nat Immunol ; 20(10): 1348-1359, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31406382

RESUMO

Helper T cells actively communicate with adjacent cells by secreting soluble mediators, yet crosstalk between helper T cells and endothelial cells remains poorly understood. Here we found that placental growth factor (PlGF), a homolog of the vascular endothelial growth factor that enhances an angiogenic switch in disease, was selectively secreted by the TH17 subset of helper T cells and promoted angiogenesis. Interestingly, the 'angio-lymphokine' PlGF, in turn, specifically induced the differentiation of pathogenic TH17 cells by activating the transcription factor STAT3 via binding to its receptors and replaced the activity of interleukin-6 in the production of interleukin-17, whereas it suppressed the generation of regulatory T cells. Moreover, T cell-derived PlGF was required for the progression of autoimmune diseases associated with TH17 differentiation, including experimental autoimmune encephalomyelitis and collagen-induced arthritis, in mice. Collectively, our findings provide insights into the PlGF-dictated links among angiogenesis, TH17 cell development and autoimmunity.


Assuntos
Artrite Experimental/imunologia , Encefalomielite Autoimune Experimental/imunologia , Fator de Crescimento Placentário/metabolismo , Linfócitos T Reguladores/imunologia , Células Th17/imunologia , Animais , Autoimunidade , Diferenciação Celular , Células Cultivadas , Interleucina-17/metabolismo , Interleucina-6/metabolismo , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Camundongos Knockout , Neovascularização Patológica , Fator de Crescimento Placentário/genética , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo
6.
Immunity ; 54(12): 2795-2811.e9, 2021 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-34788601

RESUMO

Lymphangitis and the formation of tertiary lymphoid organs (TLOs) in the mesentery are features of Crohn's disease. Here, we examined the genesis of these TLOs and their impact on disease progression. Whole-mount and intravital imaging of the ileum and ileum-draining collecting lymphatic vessels (CLVs) draining to mesenteric lymph nodes from TNFΔARE mice, a model of ileitis, revealed TLO formation at valves of CLVs. TLOs obstructed cellular and molecular outflow from the gut and were sites of lymph leakage and backflow. Tumor necrosis factor (TNF) neutralization begun at early stages of TLO formation restored lymph transport. However, robustly developed, chronic TLOs resisted regression and restoration of flow after TNF neutralization. TNF stimulation of cultured lymphatic endothelial cells reprogrammed responses to oscillatory shear stress, preventing the induction of valve-associated genes. Disrupted transport of immune cells, driven by loss of valve integrity and TLO formation, may contribute to the pathology of Crohn's disease.


Assuntos
Doença de Crohn/imunologia , Células Endoteliais/imunologia , Íleo/imunologia , Linfa/metabolismo , Vasos Linfáticos/imunologia , Mesentério/imunologia , Estruturas Linfoides Terciárias/imunologia , Fator de Necrose Tumoral alfa/metabolismo , Animais , Movimento Celular , Células Cultivadas , Modelos Animais de Doenças , Humanos , Ileíte , Linfangite , Camundongos , Camundongos Knockout , Estresse Mecânico
7.
Nature ; 614(7946): 88-94, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36653458

RESUMO

Two-dimensional (2D) materials and their heterostructures show a promising path for next-generation electronics1-3. Nevertheless, 2D-based electronics have not been commercialized, owing mainly to three critical challenges: i) precise kinetic control of layer-by-layer 2D material growth, ii) maintaining a single domain during the growth, and iii) wafer-scale controllability of layer numbers and crystallinity. Here we introduce a deterministic, confined-growth technique that can tackle these three issues simultaneously, thus obtaining wafer-scale single-domain 2D monolayer arrays and their heterostructures on arbitrary substrates. We geometrically confine the growth of the first set of nuclei by defining a selective growth area via patterning SiO2 masks on two-inch substrates. Owing to substantial reduction of the growth duration at the micrometre-scale SiO2 trenches, we obtain wafer-scale single-domain monolayer WSe2 arrays on the arbitrary substrates by filling the trenches via short growth of the first set of nuclei, before the second set of nuclei is introduced, thus without requiring epitaxial seeding. Further growth of transition metal dichalcogenides with the same principle yields the formation of single-domain MoS2/WSe2 heterostructures. Our achievement will lay a strong foundation for 2D materials to fit into industrial settings.

8.
Nature ; 614(7946): 144-152, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36509107

RESUMO

Cell adhesion molecules are ubiquitous in multicellular organisms, specifying precise cell-cell interactions in processes as diverse as tissue development, immune cell trafficking and the wiring of the nervous system1-4. Here we show that a wide array of synthetic cell adhesion molecules can be generated by combining orthogonal extracellular interactions with intracellular domains from native adhesion molecules, such as cadherins and integrins. The resulting molecules yield customized cell-cell interactions with adhesion properties that are similar to native interactions. The identity of the intracellular domain of the synthetic cell adhesion molecules specifies interface morphology and mechanics, whereas diverse homotypic or heterotypic extracellular interaction domains independently specify the connectivity between cells. This toolkit of orthogonal adhesion molecules enables the rationally programmed assembly of multicellular architectures, as well as systematic remodelling of native tissues. The modularity of synthetic cell adhesion molecules provides fundamental insights into how distinct classes of cell-cell interfaces may have evolved. Overall, these tools offer powerful abilities for cell and tissue engineering and for systematically studying multicellular organization.


Assuntos
Moléculas de Adesão Celular , Comunicação Celular , Biologia Sintética , Caderinas/química , Adesão Celular , Moléculas de Adesão Celular/química , Moléculas de Adesão Celular/metabolismo , Integrinas/química , Biologia Sintética/métodos , Domínios Proteicos , Sítios de Ligação , Engenharia Celular
9.
Nature ; 614(7946): 81-87, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36725999

RESUMO

Micro-LEDs (µLEDs) have been explored for augmented and virtual reality display applications that require extremely high pixels per inch and luminance1,2. However, conventional manufacturing processes based on the lateral assembly of red, green and blue (RGB) µLEDs have limitations in enhancing pixel density3-6. Recent demonstrations of vertical µLED displays have attempted to address this issue by stacking freestanding RGB LED membranes and fabricating top-down7-14, but minimization of the lateral dimensions of stacked µLEDs has been difficult. Here we report full-colour, vertically stacked µLEDs that achieve, to our knowledge, the highest array density (5,100 pixels per inch) and the smallest size (4 µm) reported to date. This is enabled by a two-dimensional materials-based layer transfer technique15-18 that allows the growth of RGB LEDs of near-submicron thickness on two-dimensional material-coated substrates via remote or van der Waals epitaxy, mechanical release and stacking of LEDs, followed by top-down fabrication. The smallest-ever stack height of around 9 µm is the key enabler for record high µLED array density. We also demonstrate vertical integration of blue µLEDs with silicon membrane transistors for active matrix operation. These results establish routes to creating full-colour µLED displays for augmented and virtual reality, while also offering a generalizable platform for broader classes of three-dimensional integrated devices.

10.
Immunity ; 51(1): 119-130.e5, 2019 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-31231034

RESUMO

Tissue-resident macrophages require specific milieus for the maintenance of defining gene-expression programs. Expression of the transcription factor GATA6 is required for the homeostasis, function and localization of peritoneal cavity-resident macrophages. Gata6 expression is maintained in a non-cell autonomous manner and is elicited by the vitamin A metabolite, retinoic acid. Here, we found that the GATA6 transcriptional program is a common feature of macrophages residing in all visceral body cavities. Retinoic acid-dependent and -independent hallmark genes of GATA6+ macrophages were induced by mesothelial and fibroblastic stromal cells that express the transcription factor Wilms' Tumor 1 (WT1), which drives the expression of two rate-limiting enzymes in retinol metabolism. Depletion of Wt1+ stromal cells reduced the frequency of GATA6+ macrophages in the peritoneal, pleural and pericardial cavities. Thus, Wt1+ mesothelial and fibroblastic stromal cells constitute essential niche components supporting the tissue-specifying transcriptional landscape and homeostasis of cavity-resident macrophages.


Assuntos
Fator de Transcrição GATA6/metabolismo , Macrófagos/fisiologia , Pericárdio/imunologia , Cavidade Peritoneal/fisiologia , Cavidade Pleural/imunologia , Proteínas Repressoras/metabolismo , Células Estromais/fisiologia , Animais , Diferenciação Celular , Células Cultivadas , Fator de Transcrição GATA6/genética , Homeostase , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas Repressoras/genética , Tretinoína/metabolismo , Proteínas WT1
11.
Immunity ; 47(2): 323-338.e6, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28813661

RESUMO

Tumor-associated macrophages (TAMs) are essential components of the cancer microenvironment and play critical roles in the regulation of tumor progression. Optimal therapeutic intervention requires in-depth understanding of the sources that sustain macrophages in malignant tissues. In this study, we investigated the ontogeny of TAMs in murine pancreatic ductal adenocarcinoma (PDAC) models. We identified both inflammatory monocytes and tissue-resident macrophages as sources of TAMs. Unexpectedly, significant portions of pancreas-resident macrophages originated from embryonic development and expanded through in situ proliferation during tumor progression. Whereas monocyte-derived TAMs played more potent roles in antigen presentation, embryonically derived TAMs exhibited a pro-fibrotic transcriptional profile, indicative of their role in producing and remodeling molecules in the extracellular matrix. Collectively, these findings uncover the heterogeneity of TAM origin and functions and could provide therapeutic insight for PDAC treatment.


Assuntos
Carcinogênese , Carcinoma Ductal/imunologia , Macrófagos/imunologia , Pâncreas/patologia , Neoplasias Pancreáticas/imunologia , Animais , Carcinoma Ductal/patologia , Diferenciação Celular , Linhagem Celular Tumoral , Movimento Celular , Matriz Extracelular/metabolismo , Desenvolvimento Fetal , Fibrose , Hematopoese , Macrófagos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Monócitos/imunologia , Neoplasias Pancreáticas/patologia , Microambiente Tumoral
12.
Cell ; 144(5): 745-56, 2011 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-21376235

RESUMO

The Mpk1 MAPK of the yeast cell wall integrity pathway uses a noncatalytic mechanism to activate transcription of stress-induced genes by recruitment of initiation factors to target promoters. We show here that Mpk1 additionally serves a function in transcription elongation that is also independent of its catalytic activity. This function is mediated by an interaction between Mpk1 and the Paf1 subunit of the Paf1C elongation complex. A mutation in Paf1 that blocks this interaction causes a specific defect in transcription elongation of an Mpk1-induced gene, which results from Sen1-dependent premature termination through a Nab3-binding site within the promoter-proximal region of the gene. Our findings reveal a regulatory mechanism in which Mpk1 overcomes transcriptional attenuation by blocking recruitment of the Sen1-Nrd1-Nab3 termination complex to the elongating polymerase. Finally, we demonstrate that this mechanism is conserved in an interaction between the human ERK5 MAPK and human Paf1.


Assuntos
DNA Helicases/metabolismo , Proteínas Nucleares/metabolismo , RNA Helicases/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Transcrição Gênica , Glucosiltransferases/metabolismo , Humanos , Proteínas de Membrana/metabolismo , Proteína Quinase 7 Ativada por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Regiões Promotoras Genéticas , Fatores de Transcrição
13.
Nature ; 582(7813): 511-514, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32581381

RESUMO

Decrease in processing speed due to increased resistance and capacitance delay is a major obstacle for the down-scaling of electronics1-3. Minimizing the dimensions of interconnects (metal wires that connect different electronic components on a chip) is crucial for the miniaturization of devices. Interconnects are isolated from each other by non-conducting (dielectric) layers. So far, research has mostly focused on decreasing the resistance of scaled interconnects because integration of dielectrics using low-temperature deposition processes compatible with complementary metal-oxide-semiconductors is technically challenging. Interconnect isolation materials must have low relative dielectric constants (κ values), serve as diffusion barriers against the migration of metal into semiconductors, and be thermally, chemically and mechanically stable. Specifically, the International Roadmap for Devices and Systems recommends4 the development of dielectrics with κ values of less than 2 by 2028. Existing low-κ materials (such as silicon oxide derivatives, organic compounds and aerogels) have κ values greater than 2 and poor thermo-mechanical properties5. Here we report three-nanometre-thick amorphous boron nitride films with ultralow κ values of 1.78 and 1.16 (close to that of air, κ = 1) at operation frequencies of 100 kilohertz and 1 megahertz, respectively. The films are mechanically and electrically robust, with a breakdown strength of 7.3 megavolts per centimetre, which exceeds requirements. Cross-sectional imaging reveals that amorphous boron nitride prevents the diffusion of cobalt atoms into silicon under very harsh conditions, in contrast to reference barriers. Our results demonstrate that amorphous boron nitride has excellent low-κ dielectric characteristics for high-performance electronics.

14.
Immunity ; 45(3): 468-470, 2016 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-27653599

RESUMO

Macrophages residing in different organs have diverse gene-expression programs. Mass et al. (2016) propose that this diversity develops "at home"-within those organs-after the recruitment of a common precursor that had not made prior commitments to diversity.


Assuntos
Macrófagos/fisiologia , Animais , Expressão Gênica/fisiologia
15.
Proc Natl Acad Sci U S A ; 119(35): e2121251119, 2022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-35994670

RESUMO

GCN2 (general control nonderepressible 2) is a serine/threonine-protein kinase that controls messenger RNA translation in response to amino acid availability and ribosome stalling. Here, we show that GCN2 controls erythrocyte clearance and iron recycling during stress. Our data highlight the importance of liver macrophages as the primary cell type mediating these effects. During different stress conditions, such as hemolysis, amino acid deficiency or hypoxia, GCN2 knockout (GCN2-/-) mice displayed resistance to anemia compared with wild-type (GCN2+/+) mice. GCN2-/- liver macrophages exhibited defective erythrophagocytosis and lysosome maturation. Molecular analysis of GCN2-/- cells demonstrated that the ATF4-NRF2 pathway is a critical downstream mediator of GCN2 in regulating red blood cell clearance and iron recycling.


Assuntos
Aminoácidos , Eritrócitos , Ferro , Fígado , Macrófagos , Proteínas Serina-Treonina Quinases , Fator 4 Ativador da Transcrição/metabolismo , Aminoácidos/deficiência , Aminoácidos/metabolismo , Anemia/metabolismo , Animais , Citofagocitose , Eritrócitos/metabolismo , Deleção de Genes , Hemólise , Hipóxia/metabolismo , Ferro/metabolismo , Fígado/citologia , Lisossomos/metabolismo , Macrófagos/metabolismo , Camundongos , Camundongos Knockout , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas Serina-Treonina Quinases/deficiência , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Estresse Fisiológico
16.
Genomics ; 116(2): 110805, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38309446

RESUMO

The gut plays a key role in regulating metabolic health. Dietary factors disrupt intestinal physiology and contribute to obesity and diabetes, whereas bariatric procedures such as vertical sleeve gastrectomy (VSG) cause gut adaptations that induce robust metabolic improvements. However, our understanding of these adaptations at the cellular and molecular levels remains limited. In a validated murine model, we leverage single-cell transcriptomics to determine how VSG impacts different cell lineages of the small intestinal epithelium. We define cell type-specific genes and pathways that VSG rescues from high-fat diet perturbation and characterize additional rescue-independent changes brought about by VSG. We show that Paneth cells have increased expression of the gut peptide Reg3g after VSG. We also find that VSG restores pathways pertaining to mitochondrial respiration and cellular metabolism, especially within crypt-based cells. Overall, our study provides unprecedented molecular resolution of VSG's therapeutic effects on the gut epithelium.


Assuntos
Gastrectomia , Obesidade , Camundongos , Humanos , Animais , Gastrectomia/métodos , Mucosa Intestinal/metabolismo , Dieta Hiperlipídica/efeitos adversos
17.
Nano Lett ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38985008

RESUMO

Recently, 2D semiconductor-based optoelectronic memory has been explored to overcome the limitations of conventional von Neumann architectures by integrating optical sensing and data storage into one device. Persistent photocurrent (PPC), essential for optoelectronic memory, originates from charge carrier trapping according to the Shockley-Read-Hall (SRH) model in 2D semiconductors. The quasi-Fermi level position influences the activation of charge-trapping sites. However, the correlation between quasi-Fermi level modulations and PPC in 2D semiconductors has not been extensively studied. In this study, we demonstrate optoelectronic memory based on a 2D semiconductor-polymer hybrid structure and confirm that the underlying mechanism is charge trapping, as the SRH model explains. Under light illumination, electrons transfer from polyvinylpyrrolidone to p-type tungsten diselenide, resulting in high-level injection and majority carrier-type transitions. The quasi-Fermi level shifts upward with increasing temperature, improving PPC and enabling optoelectronic memory at 433 K. Our findings offer valuable insights into optimizing 2D semiconductor-based optoelectronic memory.

18.
Clin Infect Dis ; 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38321565

RESUMO

A 32-year-old female with advanced HIV infection presented to an Australian hospital with subacute but worsening symptoms of encephalitis. Metagenomic sequencing and Dengue NS3 antigen staining of brain tissue confirmed active Dengue virus (DENV) encephalitis. The most recent possible DENV exposure was months prior in West Africa, indicating chronicity.

19.
Neuroimage ; 288: 120533, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38340880

RESUMO

AIM: Brain volume is influenced by several factors that can change throughout the day. In addition, most of these factors are influenced by sleep quality. This study investigated diurnal variation in brain volume and its relation to overnight sleep quality. METHODS: We enrolled 1,003 healthy Koreans without any psychiatric disorders aged 60 years or older. We assessed sleep quality and average wake time using the Pittsburgh Sleep Quality Index, and divided sleep quality into good, moderate, and poor groups. We estimated the whole and regional brain volumes from three-dimensional T1-weighted brain MRI scans. We divided the interval between average wake-up time and MRI acquisition time (INT) into tertile groups: short (INT1), medium (INT2), and long (INT3). RESULTS: Whole and regional brain volumes showed no significance with respect to INT. However, the `interaction between INT and sleep quality showed significance for whole brain, cerebral gray matter, and cerebrospinal fluid volumes (p < .05). The INT2 group showed significantly lower volumes of whole brain, whole gray matter, cerebral gray matter, cortical gray matter, subcortical gray matter, and cerebrospinal fluid than the INT1 and INT3 groups only in the individuals with good sleep quality. CONCLUSION: Human brain volume changes significantly within a day associated with overnight sleep in the individuals with good sleep quality.


Assuntos
Encéfalo , Qualidade do Sono , Humanos , Idoso , Estudos Transversais , Estudos Retrospectivos , Encéfalo/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos
20.
Breast Cancer Res ; 26(1): 68, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649889

RESUMO

BACKGROUND: Artificial intelligence (AI) algorithms for the independent assessment of screening mammograms have not been well established in a large screening cohort of Asian women. We compared the performance of screening digital mammography considering breast density, between radiologists and AI standalone detection among Korean women. METHODS: We retrospectively included 89,855 Korean women who underwent their initial screening digital mammography from 2009 to 2020. Breast cancer within 12 months of the screening mammography was the reference standard, according to the National Cancer Registry. Lunit software was used to determine the probability of malignancy scores, with a cutoff of 10% for breast cancer detection. The AI's performance was compared with that of the final Breast Imaging Reporting and Data System category, as recorded by breast radiologists. Breast density was classified into four categories (A-D) based on the radiologist and AI-based assessments. The performance metrics (cancer detection rate [CDR], sensitivity, specificity, positive predictive value [PPV], recall rate, and area under the receiver operating characteristic curve [AUC]) were compared across breast density categories. RESULTS: Mean participant age was 43.5 ± 8.7 years; 143 breast cancer cases were identified within 12 months. The CDRs (1.1/1000 examination) and sensitivity values showed no significant differences between radiologist and AI-based results (69.9% [95% confidence interval [CI], 61.7-77.3] vs. 67.1% [95% CI, 58.8-74.8]). However, the AI algorithm showed better specificity (93.0% [95% CI, 92.9-93.2] vs. 77.6% [95% CI, 61.7-77.9]), PPV (1.5% [95% CI, 1.2-1.9] vs. 0.5% [95% CI, 0.4-0.6]), recall rate (7.1% [95% CI, 6.9-7.2] vs. 22.5% [95% CI, 22.2-22.7]), and AUC values (0.8 [95% CI, 0.76-0.84] vs. 0.74 [95% CI, 0.7-0.78]) (all P < 0.05). Radiologist and AI-based results showed the best performance in the non-dense category; the CDR and sensitivity were higher for radiologists in the heterogeneously dense category (P = 0.059). However, the specificity, PPV, and recall rate consistently favored AI-based results across all categories, including the extremely dense category. CONCLUSIONS: AI-based software showed slightly lower sensitivity, although the difference was not statistically significant. However, it outperformed radiologists in recall rate, specificity, PPV, and AUC, with disparities most prominent in extremely dense breast tissue.


Assuntos
Inteligência Artificial , Densidade da Mama , Neoplasias da Mama , Detecção Precoce de Câncer , Mamografia , Radiologistas , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Neoplasias da Mama/epidemiologia , Mamografia/métodos , Adulto , Pessoa de Meia-Idade , Detecção Precoce de Câncer/métodos , Estudos Retrospectivos , República da Coreia/epidemiologia , Curva ROC , Mama/diagnóstico por imagem , Mama/patologia , Algoritmos , Programas de Rastreamento/métodos , Sensibilidade e Especificidade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA