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1.
Nat Immunol ; 22(11): 1440-1451, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34686860

RESUMEN

Intestinal epithelial cell (IEC) damage by T cells contributes to graft-versus-host disease, inflammatory bowel disease and immune checkpoint blockade-mediated colitis. But little is known about the target cell-intrinsic features that affect disease severity. Here we identified disruption of oxidative phosphorylation and an increase in succinate levels in the IECs from several distinct in vivo models of T cell-mediated colitis. Metabolic flux studies, complemented by imaging and protein analyses, identified disruption of IEC-intrinsic succinate dehydrogenase A (SDHA), a component of mitochondrial complex II, in causing these metabolic alterations. The relevance of IEC-intrinsic SDHA in mediating disease severity was confirmed by complementary chemical and genetic experimental approaches and validated in human clinical samples. These data identify a critical role for the alteration of the IEC-specific mitochondrial complex II component SDHA in the regulation of the severity of T cell-mediated intestinal diseases.


Asunto(s)
Colitis/enzimología , Colon/enzimología , Citotoxicidad Inmunológica , Complejo II de Transporte de Electrones/metabolismo , Células Epiteliales/enzimología , Enfermedad Injerto contra Huésped/enzimología , Mucosa Intestinal/enzimología , Mitocondrias/enzimología , Linfocitos T/inmunología , Animales , Estudios de Casos y Controles , Comunicación Celular , Células Cultivadas , Colitis/genética , Colitis/inmunología , Colitis/patología , Colon/inmunología , Colon/ultraestructura , Modelos Animales de Enfermedad , Complejo II de Transporte de Electrones/genética , Células Epiteliales/inmunología , Células Epiteliales/ultraestructura , Femenino , Enfermedad Injerto contra Huésped/genética , Enfermedad Injerto contra Huésped/inmunología , Enfermedad Injerto contra Huésped/patología , Humanos , Inmunidad Mucosa , Mucosa Intestinal/inmunología , Mucosa Intestinal/ultraestructura , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Transgénicos , Mitocondrias/inmunología , Mitocondrias/ultraestructura , Fosforilación Oxidativa , Ácido Succínico/metabolismo , Linfocitos T/metabolismo
2.
Nature ; 618(7963): 151-158, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37198494

RESUMEN

Pancreatic ductal adenocarcinoma (PDA) is a lethal disease notoriously resistant to therapy1,2. This is mediated in part by a complex tumour microenvironment3, low vascularity4, and metabolic aberrations5,6. Although altered metabolism drives tumour progression, the spectrum of metabolites used as nutrients by PDA remains largely unknown. Here we identified uridine as a fuel for PDA in glucose-deprived conditions by assessing how more than 175 metabolites impacted metabolic activity in 21 pancreatic cell lines under nutrient restriction. Uridine utilization strongly correlated with the expression of uridine phosphorylase 1 (UPP1), which we demonstrate liberates uridine-derived ribose to fuel central carbon metabolism and thereby support redox balance, survival and proliferation in glucose-restricted PDA cells. In PDA, UPP1 is regulated by KRAS-MAPK signalling and is augmented by nutrient restriction. Consistently, tumours expressed high UPP1 compared with non-tumoural tissues, and UPP1 expression correlated with poor survival in cohorts of patients with PDA. Uridine is available in the tumour microenvironment, and we demonstrated that uridine-derived ribose is actively catabolized in tumours. Finally, UPP1 deletion restricted the ability of PDA cells to use uridine and blunted tumour growth in immunocompetent mouse models. Our data identify uridine utilization as an important compensatory metabolic process in nutrient-deprived PDA cells, suggesting a novel metabolic axis for PDA therapy.


Asunto(s)
Glucosa , Neoplasias Pancreáticas , Ribosa , Microambiente Tumoral , Uridina , Animales , Ratones , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patología , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Ribosa/metabolismo , Uridina/química , Glucosa/deficiencia , División Celular , Línea Celular Tumoral , Sistema de Señalización de MAP Quinasas , Uridina Fosforilasa/deficiencia , Uridina Fosforilasa/genética , Uridina Fosforilasa/metabolismo , Humanos
3.
Nature ; 612(7940): 470-476, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36517715

RESUMEN

Quantitative determination and in situ monitoring of molecular chirality at extremely low concentrations is still challenging with simple optics because of the molecular-scale mismatch with the incident light wavelength. Advances in spectroscopy1-4 and nanophotonics have successfully lowered the detection limit in enantioselective sensing, as it can bring the microscopic chiral characteristics of molecules into the macroscopic scale5-7 or squeeze the chiral light into the subwavelength scale8-17. Conventional nanophotonic approaches depend mainly on the optical helicity density8,9 by localized resonances within an individual structure, such as localized surface plasmon resonances (LSPRs)10-16 or dielectric Mie resonances17. These approaches use the local chiral hotspots in the immediate vicinity of the structure, whereas the handedness of these hotspots varies spatially. As such, these localized resonance modes tend to be error-prone to the stochasticity of the target molecular orientations, vibrations and local concentrations18,19. Here we identified enantioselective characteristics of collective resonances (CRs)20 arising from assembled 2D crystals of isotropic, 432-symmetric chiral gold nanoparticles (helicoids)21,22. The CRs exhibit a strong and uniform chiral near field over a large volume above the 2D crystal plane, resulting from the collectively spinning, optically induced dipoles at each helicoid. Thus, energy redistribution by molecular back action on the chiral near field shifts the CRs in opposite directions, depending on the handedness of the analyte, maximizing the modulation of the collective circular dichroism (CD).

4.
Nature ; 609(7928): 754-760, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35940203

RESUMEN

Identifying the host genetic factors underlying severe COVID-19 is an emerging challenge1-5. Here we conducted a genome-wide association study (GWAS) involving 2,393 cases of COVID-19 in a cohort of Japanese individuals collected during the initial waves of the pandemic, with 3,289 unaffected controls. We identified a variant on chromosome 5 at 5q35 (rs60200309-A), close to the dedicator of cytokinesis 2 gene (DOCK2), which was associated with severe COVID-19 in patients less than 65 years of age. This risk allele was prevalent in East Asian individuals but rare in Europeans, highlighting the value of genome-wide association studies in non-European populations. RNA-sequencing analysis of 473 bulk peripheral blood samples identified decreased expression of DOCK2 associated with the risk allele in these younger patients. DOCK2 expression was suppressed in patients with severe cases of COVID-19. Single-cell RNA-sequencing analysis (n = 61 individuals) identified cell-type-specific downregulation of DOCK2 and a COVID-19-specific decreasing effect of the risk allele on DOCK2 expression in non-classical monocytes. Immunohistochemistry of lung specimens from patients with severe COVID-19 pneumonia showed suppressed DOCK2 expression. Moreover, inhibition of DOCK2 function with CPYPP increased the severity of pneumonia in a Syrian hamster model of SARS-CoV-2 infection, characterized by weight loss, lung oedema, enhanced viral loads, impaired macrophage recruitment and dysregulated type I interferon responses. We conclude that DOCK2 has an important role in the host immune response to SARS-CoV-2 infection and the development of severe COVID-19, and could be further explored as a potential biomarker and/or therapeutic target.


Asunto(s)
COVID-19 , Proteínas Activadoras de GTPasa , Estudio de Asociación del Genoma Completo , Factores de Intercambio de Guanina Nucleótido , Interacciones Microbiota-Huesped , SARS-CoV-2 , Alelos , Animales , COVID-19/complicaciones , COVID-19/genética , COVID-19/inmunología , COVID-19/fisiopatología , Modelos Animales de Enfermedad , Proteínas Activadoras de GTPasa/antagonistas & inhibidores , Proteínas Activadoras de GTPasa/genética , Proteínas Activadoras de GTPasa/metabolismo , Predisposición Genética a la Enfermedad , Factores de Intercambio de Guanina Nucleótido/antagonistas & inhibidores , Factores de Intercambio de Guanina Nucleótido/genética , Factores de Intercambio de Guanina Nucleótido/metabolismo , Interacciones Microbiota-Huesped/genética , Interacciones Microbiota-Huesped/inmunología , Humanos , Interferón Tipo I/genética , Interferón Tipo I/inmunología , Japón , Pulmón/patología , Macrófagos , Mesocricetus , Persona de Mediana Edad , Neumonía/complicaciones , Pirazoles/farmacología , RNA-Seq , SARS-CoV-2/patogenicidad , Carga Viral , Pérdida de Peso
5.
EMBO J ; 42(19): e113481, 2023 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-37575012

RESUMEN

The NLRP3 inflammasome plays a key role in responding to pathogens, and endogenous damage and mitochondria are intensively involved in inflammasome activation. The NLRP3 inflammasome forms multiprotein complexes and its sequential assembly is important for its activation. Here, we show that NLRP3 is ubiquitinated by the mitochondria-associated E3 ligase, MARCH5. Myeloid cell-specific March5 conditional knockout (March5 cKO) mice failed to secrete IL-1ß and IL-18 and exhibited an attenuated mortality rate upon LPS or Pseudomonas aeruginosa challenge. Macrophages derived from March5 cKO mice also did not produce IL-1ß and IL-18 after microbial infection. Mechanistically, MARCH5 interacts with the NACHT domain of NLRP3 and promotes K27-linked polyubiquitination on K324 and K430 residues of NLRP3. Ubiquitination-defective NLRP3 mutants on K324 and K430 residues are not able to bind to NEK7, nor form NLRP3 oligomers leading to abortive ASC speck formation and diminished IL-1ß production. Thus, MARCH5-dependent NLRP3 ubiquitination on the mitochondria is required for NLRP3-NEK7 complex formation and NLRP3 oligomerization. We propose that the E3 ligase MARCH5 is a regulator of NLRP3 inflammasome activation on the mitochondria.


Asunto(s)
Inflamasomas , Proteína con Dominio Pirina 3 de la Familia NLR , Animales , Ratones , Inflamasomas/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Interleucina-18/metabolismo , Ubiquitinación , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Caspasa 1/metabolismo
6.
Hum Mol Genet ; 32(4): 677-684, 2023 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-36164742

RESUMEN

Crohn's disease (CD) and ulcerative colitis (UC), two major subtypes of inflammatory bowel disease, show substantial differences in their clinical course and treatment response. To identify the genetic factors underlying the distinct characteristics of these two diseases, we performed a genome-wide association study (GWAS) between CD (n = 2359) and UC (n = 2175) in a Korean population, followed by replication in an independent sample of 772 CD and 619 UC cases. Two novel loci were identified with divergent effects on CD and UC: rs9842650 in CD200 and rs885026 in NCOR2. In addition, the seven established susceptibility loci [major histocompatibility complex (MHC), TNFSF15, OTUD3, USP12, IL23R, FCHSD2 and RIPK2] reached genome-wide significance. Of the nine loci, six (MHC, TNFSF15, OTUD3, USP12, IL23R and CD200) were replicated in the case-case GWAS of European populations. The proportion of variance explained in CD-UC status by polygenic risk score analysis was up to 22.6%. The area under the receiver-operating characteristic curve value was 0.74, suggesting acceptable discrimination between CD and UC. This CD-UC GWAS provides new insights into genetic differences between the two diseases with similar symptoms and might be useful in improving their diagnosis and treatment.


Asunto(s)
Colitis Ulcerosa , Enfermedad de Crohn , Humanos , Colitis Ulcerosa/genética , Enfermedad de Crohn/genética , Estudio de Asociación del Genoma Completo , Predisposición Genética a la Enfermedad , Sitios Genéticos , Polimorfismo de Nucleótido Simple/genética , Miembro 15 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral/genética , Proteínas Portadoras/genética , Proteínas de la Membrana/genética , Proteasas Ubiquitina-Específicas/genética
7.
PLoS Genet ; 18(2): e1010092, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35226663

RESUMEN

Hox genes encode evolutionarily conserved transcription factors that specify regional identities along the anterior-posterior (A-P) axis. Although some Hox genes are known to regulate the differentiation of certain neurons, to what extent Hox genes are involved in the terminal specification of the entire nervous system is unclear. Here, we systematically mapped the expression of all six Hox genes in C. elegans nervous system and found Hox expression in 97 (32%) of the 302 neurons in adult hermaphrodites. Our results are generally consistent with previous high-throughput expression mapping and single-cell transcriptomic studies. Detailed analysis of the fate markers for these neurons revealed that Hox genes regulate the differentiation of 29 (25%) of the 118 classes of C. elegans neurons. Hox genes not only regulate the specification of terminal neuronal fates through multiple mechanisms but also control subtype diversification along the A-P axis. The widespread involvement of Hox genes in neuronal differentiation indicates their roles in establishing complex nervous systems.


Asunto(s)
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animales , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Genes Homeobox/genética , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Neuronas/metabolismo
8.
Neuroimage ; 288: 120528, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38311125

RESUMEN

Quantitative susceptibility mapping (QSM) is frequently employed in investigating brain iron related to brain development and diseases within deep gray matter (DGM). Nonetheless, the acquisition of whole-brain QSM data is time-intensive. An alternative approach, focusing the QSM specifically on areas of interest such as the DGM by reducing the field-of-view (FOV), can significantly decrease scan times. However, severe susceptibility value underestimations have been reported during QSM reconstruction with a limited FOV, largely attributable to artifacts from incorrect background field removal in the boundary region. This presents a considerable barrier to the clinical use of QSM with small spatial coverages using conventional methods alone. To mitigate the propagation of these errors, we proposed a harmonic field extension method based on a physics-informed generative adversarial network. Both quantitative and qualitative results demonstrate that our method outperforms conventional methods and delivers results comparable to those obtained with full FOV. Furthermore, we demonstrate the versatility of our method by applying it to data acquired prospectively with limited FOV and to data from patients with Parkinson's disease. The method has shown significant improvements in local field results, with QSM outcomes. In a clear illustration of its feasibility and effectiveness in real clinical environments, our proposed method addresses the prevalent issue of susceptibility underestimation in QSM with small spatial coverage.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Algoritmos , Encéfalo/diagnóstico por imagen , Mapeo Encefálico/métodos
9.
Breast Cancer Res ; 26(1): 72, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38664825

RESUMEN

BACKGROUND: Breast cancer, the most prevalent cancer in women worldwide, faces treatment challenges due to drug resistance, posing a serious threat to patient survival. The present study aimed to identify the key molecules that drive drug resistance and aggressiveness in breast cancer cells and validate them as therapeutic targets. METHODS: Transcriptome microarray and analysis using PANTHER pathway and StemChecker were performed to identify the most significantly expressed genes in tamoxifen-resistant and adriamycin-resistant MCF-7 breast cancer cells. Clinical relevance of the key genes was determined using Kaplan-Meier survival analyses on The Cancer Genome Atlas dataset of breast cancer patients. Gene overexpression/knockdown, spheroid formation, flow cytometric analysis, chromatin immunoprecipitation, immunocytochemistry, wound healing/transwell migration assays, and cancer stem cell transcription factor activation profiling array were used to elucidate the regulatory mechanism of integrin α11 expression. Tumour-bearing xenograft models were used to demonstrate integrin α11 is a potential therapeutic target. RESULTS: Integrin α11 was consistently upregulated in drug-resistant breast cancer cells, and its silencing inhibited cancer stem cells (CSCs) and epithelial-mesenchymal transition (EMT) while restoring sensitivity to anticancer drugs. HIF1α, GLI-1, and EZH2 contributed the most to the regulation of integrin α11 and EZH2 expression, with EZH2 being more necessary for EZH2 autoinduction than HIF1α and GLI-1. Additionally, unlike HIF1α or EZH2, GLI-1 was the sole transcription factor activated by integrin-linked focal adhesion kinase, indicating GLI-1 as a key driver of the EZH2-integrin α11 axis operating for cancer stem cell survival and EMT. Kaplan-Meier survival analysis using The Cancer Genome Atlas (TCGA) dataset also revealed both EZH2 and integrin α11 could be strong prognostic factors of relapse-free and overall survival in breast cancer patients. However, the superior efficacy of integrin α11 siRNA therapy over EZH2 siRNA treatment was demonstrated by enhanced inhibition of tumour growth and prolonged survival in murine models bearing tumours. CONCLUSION: Our findings elucidate that integrin α11 is upregulated by EZH2, forming a positive feedback circuit involving FAK-GLI-1 and contributing to drug resistance, cancer stem cell survival and EMT. Taken together, the results suggest integrin α11 as a promising prognostic marker and a powerful therapeutic target for drug-resistant breast cancer.


Asunto(s)
Neoplasias de la Mama , Resistencia a Antineoplásicos , Proteína Potenciadora del Homólogo Zeste 2 , Transición Epitelial-Mesenquimal , Regulación Neoplásica de la Expresión Génica , Células Madre Neoplásicas , ARN Interferente Pequeño , Ensayos Antitumor por Modelo de Xenoinjerto , Humanos , Resistencia a Antineoplásicos/genética , Femenino , Neoplasias de la Mama/patología , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/terapia , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Proteína Potenciadora del Homólogo Zeste 2/genética , Animales , Ratones , Transición Epitelial-Mesenquimal/genética , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , ARN Interferente Pequeño/genética , Línea Celular Tumoral , Progresión de la Enfermedad , Células MCF-7 , Proliferación Celular , Perfilación de la Expresión Génica
10.
Hum Mol Genet ; 31(22): 3934-3944, 2022 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-35512355

RESUMEN

Genome-wide association studies (GWAS) of Crohn's disease (CD) in European and leprosy in Chinese population have shown that CD and leprosy share genetic risk loci. As these shared loci were identified through cross-comparisons across different ethnic populations, we hypothesized that meta-analysis of GWAS on CD and leprosy in East Asian populations would increase power to identify additional shared loci. We performed a cross-disease meta-analysis of GWAS data from CD (1621 cases and 4419 controls) and leprosy (2901 cases 3801 controls) followed by replication in additional datasets comprising 738 CD cases and 488 controls and 842 leprosy cases and 925 controls. We identified one novel locus at 7p22.3, rs77992257 in intron 2 of ADAP1, shared between CD and leprosy with genome-wide significance (P = 3.80 × 10-11) and confirmed 10 previously established loci in both diseases: IL23R, IL18RAP, IL12B, RIPK2, TNFSF15, ZNF365-EGR2, CCDC88B, LACC1, IL27, NOD2. Phenotype variance explained by the polygenic risk scores derived from Chinese leprosy data explained up to 5.28% of variance of Korean CD, supporting similar genetic structures between the two diseases. Although CD and leprosy shared a substantial number of genetic susceptibility loci in East Asians, the majority of shared susceptibility loci showed allelic effects in the opposite direction. Investigation of the genetic correlation using cross-trait linkage disequilibrium score regression also showed a negative genetic correlation between CD and leprosy (rg [SE] = -0.40[0.13], P = 2.6 × 10-3). These observations implicate the possibility that CD might be caused by hyper-sensitive reactions toward pathogenic stimuli.


Asunto(s)
Enfermedad de Crohn , Lepra , Humanos , Estudio de Asociación del Genoma Completo , Enfermedad de Crohn/genética , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple/genética , Pueblo Asiatico/genética , Sitios Genéticos , Lepra/genética , Estudios de Casos y Controles , Miembro 15 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral/genética
11.
Anal Chem ; 96(24): 9894-9900, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38834937

RESUMEN

Surface-enhanced Raman optical activity (SEROA) is a promising method for analyzing chiral molecules' molecular chirality and structural changes. However, conventional SEROA measurements face challenges related to substrate stability, signal uniformity, and interference from electronic circular dichroism (ECD). Therefore, in this study, we present a uniform and stable substrate for SEROA measurements by utilizing Au nanoparticles on the Au nanofilm structure to confine hotspots to the film-particle junctions and minimize ECD interference. This method also uses the induction of chirality from chiral molecules to achiral molecules to overcome the limitation of chiral molecules in SEROA measurements, specifically their lower signal efficiency. Successful chirality transfer is demonstrated through distinguishable SEROA signals when the l/d-alanine mixture is present. Enantiomeric discrimination of different l/d-alanine ratios was achieved with linear responses in the circular intensity difference (CID). Altogether, the proposed chiral-induced SEROA on the AuNP_on_AuNF substrate shows promising potential for detecting and characterizing structural changes in biomolecules, thus making it a valuable tool for various research applications.

12.
J Comput Chem ; 45(3): 183-192, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-37707426

RESUMEN

The core ionization energies of second- and third-period elements of the molecules C2 H5 NO2 , SiF4 , Si(CH3 )4 , PF3 , POF3 , PSF3 , CS2 , OCS, SO2 , SO2 F2 , CH3 Cl, CFCl3 , SF5 Cl, and Cl3 PS are calculated by using Hartree-Fock (HF), and Kohn-Sham (KS) with BH&HLYP, B3LYP, and LC-BOP functionals. We used ΔSCF, Slater's transition state (STS), and two previously proposed shifted STS (1) and shifted STS (2) methods, which have been developed. The errors of ΔSCF and STS come mainly from the self-interaction errors (SIE) and can be corrected with a shifting scheme. In this study, we used the shifting parameters determined for each atom. The shifted STS (1) reproduces ΔSCF almost perfectly with mean absolute deviations (MAD) of 0.02 eV. While ΔSCF and STS vary significantly depending on the functional used, the variation of shifted STS (2) is small, and all shifted STS (2) values are close to the observed ones. The deviations of the shifted STS (2) from the experiment are 0.24 eV (BH&HLYP), 0.19 eV (B3LYP), and 0.23 eV (LC-BOP). These results further support the use of shifted STS methods for predicting the core ionization energies.

13.
Small ; 20(1): e2300557, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37641190

RESUMEN

Nanomaterials that can be easily processed into thin films are highly desirable for their wide range of applicability in electrical and optical devices. Currently, Te-based 2D materials are of interest because of their superior electrical properties compared to transition metal dichalcogenide materials. However, the large-scale manufacturing of these materials is challenging, impeding their commercialization. This paper reports on ultrathin, large-scale, and highly flexible Te and Te-metal nanorope films grown via low-power radiofrequency sputtering for a short period at 25 °C. Additionally, the feasibility of such films as transistor channels and flexible transparent conductive electrodes is discussed. A 20 nm thick Te-Ni-nanorope-channel-based transistor exhibits a high mobility (≈450 cm2 V-1 s-1 ) and on/off ratio (105 ), while 7 nm thick Te-W nanorope electrodes exhibit an extremely low haze (1.7%) and sheet resistance (30 Ω sq-1 ), and high transmittance (86.4%), work function (≈4.9 eV), and flexibility. Blue organic light-emitting diodes with 7 nm Te-W anodes exhibit significantly higher external quantum efficiencies (15.7%), lower turn-on voltages (3.2 V), and higher and more uniform viewing angles than indium-tin-oxide-based devices. The excellent mechanical flexibility and easy coating capability offered by Te nanoropes demonstrate their superiority over conventional nanomaterials and provide an effective outlet for multifunctional devices.

14.
Small ; : e2310013, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38477696

RESUMEN

Nanomaterials like graphene and transition metal dichalcogenides are being explored for developing artificial photosensory synapses with low-power optical plasticity and high retention time for practical nervous system implementation. However, few studies are conducted on Tellurium (Te)-based nanomaterials due to their direct and small bandgaps. This paper reports the superior photo-synaptic properties of covalently bonded Tellurium sulfur oxide (TeSOx ) and Tellurium selenium oxide (TeSeOx )nanomaterials, which are fabricated by incorporating S and Se atoms on the surface of Te multiropes using vapor deposition. Unlike pure Te multiropes, the TeSOx and TeSeOx multiropes exhibit controllable temporal dynamics under optical stimulation. For example, the TeSOx multirope-based transistor displays a photosensory synaptic response to UV light (λ = 365 nm). Furthermore, the TeSeOx multirope-based transistor exhibits photosensory synaptic responses to UV-vis light (λ = 365, 565, and 660 nm), reliable electrical performance, and a combination of both photodetector and optical artificial synaptic properties with a maximum responsivity of 1500 AW-1 to 365 nm UV light. This result is among the highest reported for Te-heterostructure-based devices, enabling optical artificial synaptic applications with low voltage spikes (1 V) and low light intensity (21 µW cm-2 ), potentially useful for optical neuromorphic computing.

15.
Small ; : e2312249, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38618929

RESUMEN

Phase-change random access memory represents a notable advancement in nonvolatile memory technology; however, it faces challenges in terms of thermal stability and reliability, hindering its broader application. To mitigate these issues, doping and structural modification techniques such as phase-change heterostructures (PCH) are widely studied. Although doping typically enhances thermal stability, it can adversely affect the switching speed. Structural modifications such as PCH have struggled to sustain stable performance under high atmospheric conditions. In this study, these challenges are addressed by synergizing oxygen-doped Sb2Te3 (OST) with PCH technology. This study presents a novel approach in which OST significantly improves the crystallization temperature, power efficiency, and cyclability. Subsequently, the integration of the PCH technology bolsters the switching speed and further amplifies the device's reliability and endurance by refining the grain size (≈7 nm). The resultant OST-PCH devices exhibit exceptional performance metrics, including a drift coefficient of 0.003 in the RESET state, endurance of ≈4 × 108 cycles, an switching speed of 300 ns, and 67.6 pJ of RESET energy. These findings suggest that the OST-PCH devices show promise for integration into embedded systems, such as those found in automotive applications and Internet of Things devices.

16.
Am J Pathol ; 193(7): 866-882, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37024046

RESUMEN

The disease severity of coronavirus disease 2019 (COVID-19) varies considerably from asymptomatic to serious, with fatal complications associated with dysregulation of innate and adaptive immunity. Lymphoid depletion in lymphoid tissues and lymphocytopenia have both been associated with poor disease outcomes in patients with COVID-19, but the mechanisms involved remain elusive. In this study, human angiotensin-converting enzyme 2 (hACE2) transgenic mouse models susceptible to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection were used to investigate the characteristics and determinants of lethality associated with the lymphoid depletion observed in SARS-CoV-2 infection. The lethality of Wuhan SARS-CoV-2 infection in K18-hACE2 mice was characterized by severe lymphoid depletion and apoptosis in lymphoid tissues related to fatal neuroinvasion. The lymphoid depletion was associated with a decreased number of antigen-presenting cells (APCs) and their suppressed functionality below basal levels. Lymphoid depletion with reduced APC function was a specific feature observed in SARS-CoV-2 infection but not in influenza A infection and had the greatest prognostic value for disease severity in murine COVID-19. Comparison of transgenic mouse models resistant and susceptible to SARS-CoV-2 infection revealed that suppressed APC function could be determined by the hACE2 expression pattern and interferon-related signaling. Thus, we demonstrated that lymphoid depletion associated with suppressed APC function characterizes the lethality of COVID-19 mouse models. Our data also suggest a potential therapeutic approach to prevent the severe progression of COVID-19 by enhancing APC functionality.


Asunto(s)
COVID-19 , Ratones , Humanos , Animales , SARS-CoV-2/metabolismo , Peptidil-Dipeptidasa A/metabolismo , Ratones Transgénicos , Susceptibilidad a Enfermedades , Células Presentadoras de Antígenos , Modelos Animales de Enfermedad , Pulmón/metabolismo
17.
J Autoimmun ; 145: 103206, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38554656

RESUMEN

Crohn's disease (CD) is a chronic inflammatory disorder affecting the bowel wall. Tissue-resident memory T (Trm) cells are implicated in CD, yet their characteristics remain unclear. We aimed to investigate the transcriptional profiles and functional characteristics of Trm cells in the small bowel of CD and their interactions with immune cells. Seven patients with CD and four with ulcerative colitis as controls were included. Single-cell RNA sequencing and paired T cell receptor sequencing assessed T cell subsets and transcriptional signatures in lamina propria (LP) and submucosa/muscularis propria-enriched fractions (SM/MP) from small bowel tissue samples. We detected 58,123 T cells grouped into 16 populations, including the CD4+ Trm cells with a Th17 signature and CD8+ Trm clusters. In CD, CD4+ Trm cells with a Th17 signature, termed Th17 Trm, showed significantly increased proportions within both the LP and SM/MP areas. The Th17 Trm cluster demonstrated heightened expression of tissue-residency marker genes (ITGAE, ITGA1, and CXCR6) along with elevated levels of IL17A, IL22, CCR6, and CCL20. The clonal expansion of Th17 Trm cells in CD was accompanied by enhanced transmural dynamic potential, as indicated by significantly higher migration scores. CD-prominent Th17 Trm cells displayed an increased interferon gamma (IFNγ)-related signature possibly linked with STAT1 activation, inducing chemokines (i.e., CXCL10, CXCL8, and CXCL9) in myeloid cells. Our findings underscored the elevated Th17 Trm cells throughout the small bowel in CD, contributing to disease pathogenesis through IFNγ induction and subsequent chemokine production in myeloid cells.


Asunto(s)
Enfermedad de Crohn , Memoria Inmunológica , Células T de Memoria , Células Th17 , Humanos , Enfermedad de Crohn/inmunología , Enfermedad de Crohn/genética , Enfermedad de Crohn/patología , Células Th17/inmunología , Células Th17/metabolismo , Células T de Memoria/inmunología , Células T de Memoria/metabolismo , Masculino , Femenino , Adulto , Persona de Mediana Edad , Mucosa Intestinal/inmunología , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Biomarcadores , Perfilación de la Expresión Génica , Adulto Joven
18.
J Med Virol ; 96(3): e29506, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38445718

RESUMEN

With the global pandemic and the continuous mutations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the need for effective and broadly neutralizing treatments has become increasingly urgent. This study introduces a novel strategy that targets two aspects simultaneously, using bifunctional antibodies to inhibit both the attachment of SARS-CoV-2 to host cell membranes and viral fusion. We developed pioneering IgG4-(HR2)4 bifunctional antibodies by creating immunoglobulin G4-based and phage display-derived human monoclonal antibodies (mAbs) that specifically bind to the SARS-CoV-2 receptor-binding domain, engineered with four heptad repeat 2 (HR2) peptides. Our in vitro experiments demonstrate the superior neutralization efficacy of these engineered antibodies against various SARS-CoV-2 variants, ranging from original SARS-CoV-2 strain to the recently emerged Omicron variants, as well as SARS-CoV, outperforming the parental mAb. Notably, intravenous monotherapy with the bifunctional antibody neutralizes a SARS-CoV-2 variant in a murine model without causing significant toxicity. In summary, this study unveils the significant potential of HR2 peptide-driven bifunctional antibodies as a potent and versatile strategy for mitigating SARS-CoV-2 infections. This approach offers a promising avenue for rapid development and management in the face of the continuously evolving SARS-CoV-2 variants, holding substantial promise for pandemic control.


Asunto(s)
Anticuerpos Biespecíficos , COVID-19 , Humanos , Animales , Ratones , SARS-CoV-2/genética , Anticuerpos Monoclonales/uso terapéutico , Inmunoglobulina G , Péptidos/genética , Poder Psicológico
19.
Plant Physiol ; 193(3): 1797-1815, 2023 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-37539947

RESUMEN

Autophagy serves as an important recycling route for the growth and survival of eukaryotic organisms in nutrient-deficient conditions. Since starvation induces massive changes in the metabolic flux that are coordinated by key metabolic enzymes, specific processing steps of autophagy may be linked with metabolic flux-monitoring enzymes. We attempted to identify carbon metabolic genes that modulate autophagy using VIGS screening of 45 glycolysis- and Calvin-Benson cycle-related genes in Arabidopsis (Arabidopsis thaliana). Here, we report that three consecutive triose-phosphate-processing enzymes involved in cytosolic glycolysis, triose-phosphate-isomerase (TPI), glyceraldehyde-3-phosphate dehydrogenase (GAPC), and phosphoglycerate kinase (PGK), designated TGP, negatively regulate autophagy. Depletion of TGP enzymes causes spontaneous autophagy induction and increases AUTOPHAGY-RELATED 1 (ATG1) kinase activity. TGP enzymes interact with ATG101, a regulatory component of the ATG1 kinase complex. Spontaneous autophagy induction and abnormal growth under insufficient sugar in TGP mutants are suppressed by crossing with the atg101 mutant. Considering that triose-phosphates are photosynthates transported to the cytosol from active chloroplasts, the TGP enzymes would be strategically positioned to monitor the flow of photosynthetic sugars and modulate autophagy accordingly. Collectively, these results suggest that TGP enzymes negatively control autophagy acting upstream of the ATG1 complex, which is critical for seedling development.


Asunto(s)
Arabidopsis , Autofagia , Citosol/metabolismo , Autofagia/genética , Arabidopsis/metabolismo , Glucólisis , Fosfatos/metabolismo , Triosas/metabolismo , Gliceraldehído-3-Fosfato Deshidrogenasas/genética
20.
Ann Surg Oncol ; 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38879673

RESUMEN

BACKGROUND: We evaluated the impact of preoperative COVID-19 on early postoperative mortality in patients undergoing time-sensitive cancer surgery. METHODS: This retrospective, nationwide cohort study included adult patients who underwent various cancer (thyroid, breast, stomach, colorectal, hepatobiliary, genitourinary, lung, and multiple cancer) surgeries under general anesthesia in South Korea in 2022. Patients were grouped according to the duration from the date of COVID-19 confirmation to the date of surgery (0-2 weeks, 3-4 weeks, 5-6 weeks, and ≥7 weeks). Patients without preoperative COVID-19 also were included. Multivariable logistic regression analysis with Firth correction was performed to investigate the association between preoperative COVID-19 and 30-day and 90-day postoperative mortality. The covariates encompassed sociodemographic factors, the type of surgery, and vaccination status in addition to the aforementioned groups. RESULTS: Of the 99,555 patients analyzed, 30,933 (31.1%) were preoperatively diagnosed with COVID-19. Thirty-day mortality was increased in those who underwent surgery within 0-2 weeks after diagnosis of COVID-19 (adjusted odds ratio [OR], 1.47; 95% confidence interval [CI], 1.02-2.12; P = 0.038); beyond 2 weeks, there was no significant increase in mortality. A similar pattern was observed for 90-day mortality. Full vaccination against COVID-19 was associated with reduced 30-day (OR 0.38; 95% CI 0.29-0.50; P < 0.001) and 90-day (OR 0.39; 95% CI 0.33-0.46; P < 0.001) mortality. CONCLUSIONS: Cancer surgery within 2 weeks of COVID-19 diagnosis was associated with increased early postoperative mortality. These findings support current guidelines that recommend postponing elective surgery for at least 2 weeks after the diagnosis of COVID-19.

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