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1.
Nat Immunol ; 21(2): 158-167, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31932809

RESUMEN

STING (stimulator of interferon genes) is an important innate immune protein, but its homeostatic regulation at the resting state is unknown. Here, we identified TOLLIP as a stabilizer of STING through direct interaction to prevent its degradation. Tollip deficiency results in reduced STING protein in nonhematopoietic cells and tissues, and renders STING protein unstable in immune cells, leading to severely dampened STING signaling capacity. The competing degradation mechanism of resting-state STING requires IRE1α and lysosomes. TOLLIP mediates clearance of Huntington's disease-linked polyQ protein aggregates. Ectopically expressed polyQ proteins in vitro or endogenous polyQ proteins in Huntington's disease mouse striatum sequester TOLLIP away from STING, leading to reduced STING protein and dampened immune signaling. Tollip-/- also ameliorates STING-mediated autoimmune disease in Trex1-/- mice. Together, our findings reveal that resting-state STING protein level is strictly regulated by a constant tug-of-war between 'stabilizer' TOLLIP and 'degrader' IRE1α-lysosome that together maintain tissue immune homeostasis.


Asunto(s)
Homeostasis/inmunología , Inmunidad Innata/inmunología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteínas de la Membrana/metabolismo , Transducción de Señal/inmunología , Animales , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/metabolismo , Exodesoxirribonucleasas/deficiencia , Humanos , Péptidos y Proteínas de Señalización Intracelular/inmunología , Proteínas de la Membrana/inmunología , Ratones Noqueados , Fosfoproteínas/deficiencia
2.
Mol Cell ; 83(9): 1372-1374, 2023 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-37146568

RESUMEN

In this issue, Liu et al.1 provide structural insights into how STING remains inactive. Apo-STING adopts a bilayer conformation exhibiting head-to-head and side-to-side interactions in its autoinhibitory state on the ER. The apo-STING oligomer differs from the activated STING oligomer in its biochemical stability, protein domain contact, and membrane curvature.


Asunto(s)
Proteínas de la Membrana , Proteínas de la Membrana/metabolismo , Dominios Proteicos
3.
Immunity ; 53(1): 115-126.e5, 2020 07 14.
Artículo en Inglés | MEDLINE | ID: mdl-32640258

RESUMEN

Type I interferon (IFN) response is commonly recognized as the main signaling activity of STING. Here, we generate the Sting1S365A/S365A mutant mouse that precisely ablates IFN-dependent activities while preserving IFN-independent activities of STING. StingS365A/S365A mice protect against HSV-1 infection, despite lacking the STING-mediated IFN response. This challenges the prevailing view and suggests that STING controls HSV-1 infection through IFN-independent activities. Transcriptomic analysis reveals widespread IFN-independent activities of STING in macrophages and T cells, and STING activities in T cells are predominantly IFN independent. In mouse tumor models, T cells in the tumor experience substantial cell death that is in part mediated by IFN-independent activities of STING. We found that the tumor induces STING-mediated cell death in T cells to evade immune control. Our data demonstrate that mammalian STING possesses widespread IFN-independent activities that are important for restricting HSV-1 infection, tumor immune evasion and likely also adaptive immunity.


Asunto(s)
Herpesvirus Humano 1/inmunología , Interferón Tipo I/inmunología , Proteínas de la Membrana/inmunología , Neoplasias/inmunología , Escape del Tumor/inmunología , Inmunidad Adaptativa/inmunología , Animales , Línea Celular , Femenino , Células HEK293 , Herpes Simple/inmunología , Herpes Simple/prevención & control , Herpes Simple/virología , Humanos , Inmunidad Innata/inmunología , Interferón Tipo I/biosíntesis , Macrófagos/inmunología , Masculino , Proteínas de la Membrana/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Transducción de Señal/inmunología , Linfocitos T/inmunología
4.
EMBO J ; 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39112803

RESUMEN

The OAS-RNase L pathway is one of the oldest innate RNA sensing pathways that leads to interferon (IFN) signaling and cell death. OAS recognizes viral RNA and then activates RNase L, which subsequently cleaves both cellular and viral RNA, creating "processed RNA" as an endogenous ligand that further triggers RIG-I-like receptor signaling. However, the IFN response and antiviral activity of the OAS-RNase L pathway are weak compared to other RNA-sensing pathways. Here, we discover that the SKIV2L RNA exosome limits the antiviral capacity of the OAS-RNase L pathway. SKIV2L-deficient cells exhibit remarkably increased interferon responses to RNase L-processed RNA, resulting in heightened antiviral activity. The helicase activity of SKIV2L is indispensable for this function, acting downstream of RNase L. SKIV2L depletion increases the antiviral capacity of OAS-RNase L against RNA virus infection. Furthermore, SKIV2L loss exacerbates autoinflammation caused by human OAS1 gain-of-function mutations. Taken together, our results identify SKIV2L as a critical barrier to OAS-RNase L-mediated antiviral immunity that could be therapeutically targeted to enhance the activity of a basic antiviral pathway.

5.
Nature ; 596(7873): 570-575, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34290407

RESUMEN

The classic mode of STING activation is through binding the cyclic dinucleotide 2'3'-cyclic GMP-AMP (cGAMP), produced by the DNA sensor cyclic GMP-AMP synthase (cGAS), which is important for the innate immune response to microbial infection and autoimmune disease. Modes of STING activation that are independent of cGAS are much less well understood. Here, through a spatiotemporally resolved proximity labelling screen followed by quantitative proteomics, we identify the lysosomal membrane protein Niemann-Pick type C1 (NPC1) as a cofactor in the trafficking of STING. NPC1 interacts with STING and recruits it to the lysosome for degradation in both human and mouse cells. Notably, we find that knockout of Npc1 'primes' STING signalling by physically linking or 'tethering' STING to SREBP2 trafficking. Loss of NPC1 protein also 'boosts' STING signalling by blocking lysosomal degradation. Both priming and boosting of STING signalling are required for severe neurological disease in the Npc1-/- mouse. Genetic deletion of Sting1 (the gene that encodes STING) or Irf3, but not that of Cgas, significantly reduced the activation of microglia and relieved the loss of Purkinje neurons in the cerebellum of Npc1-/- mice, leading to improved motor function. Our study identifies a cGAS- and cGAMP-independent mode of STING activation that affects neuropathology and provides a therapeutic target for the treatment of Niemann-Pick disease type C.


Asunto(s)
Proteínas de la Membrana/metabolismo , Modelos Biológicos , Enfermedad de Niemann-Pick Tipo C/metabolismo , Transducción de Señal , Animales , Línea Celular , Cerebelo/patología , Retículo Endoplásmico/metabolismo , Aparato de Golgi/metabolismo , Humanos , Factor 3 Regulador del Interferón/metabolismo , Interferón Tipo I/inmunología , Lisosomas/metabolismo , Proteínas de la Membrana/deficiencia , Proteínas de la Membrana/genética , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Microglía/metabolismo , Destreza Motora , Enfermedades Neuroinflamatorias , Proteína Niemann-Pick C1/deficiencia , Proteína Niemann-Pick C1/genética , Proteína Niemann-Pick C1/metabolismo , Enfermedad de Niemann-Pick Tipo C/patología , Nucleótidos Cíclicos/metabolismo , Nucleotidiltransferasas/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Transporte de Proteínas , Proteolisis , Células de Purkinje/metabolismo , Proteína 2 de Unión a Elementos Reguladores de Esteroles/metabolismo
6.
Nature ; 599(7883): 67-73, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34732866

RESUMEN

Chemical doping is a key process for investigating charge transport in organic semiconductors and improving certain (opto)electronic devices1-9. N(electron)-doping is fundamentally more challenging than p(hole)-doping and typically achieves a very low doping efficiency (η) of less than 10%1,10. An efficient molecular n-dopant should simultaneously exhibit a high reducing power and air stability for broad applicability1,5,6,9,11, which is very challenging. Here we show a general concept of catalysed n-doping of organic semiconductors using air-stable precursor-type molecular dopants. Incorporation of a transition metal (for example, Pt, Au, Pd) as vapour-deposited nanoparticles or solution-processable organometallic complexes (for example, Pd2(dba)3) catalyses the reaction, as assessed by experimental and theoretical evidence, enabling greatly increased η in a much shorter doping time and high electrical conductivities (above 100 S cm-1; ref. 12). This methodology has technological implications for realizing improved semiconductor devices and offers a broad exploration space of ternary systems comprising catalysts, molecular dopants and semiconductors, thus opening new opportunities in n-doping research and applications12, 13.

7.
Proc Natl Acad Sci U S A ; 121(23): e2403557121, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38809709

RESUMEN

The Asian water tower (AWT) serves as the source of 10 major Asian river systems and supports the lives of ~2 billion people. Obtaining reliable precipitation data over the AWT is a prerequisite for understanding the water cycle within this pivotal region. Here, we quantitatively reveal that the "observed" precipitation over the AWT is considerably underestimated in view of observational evidence from three water cycle components, namely, evapotranspiration, runoff, and accumulated snow. We found that three paradoxes appear if the so-called observed precipitation is corrected, namely, actual evapotranspiration exceeding precipitation, unrealistically high runoff coefficients, and accumulated snow water equivalent exceeding contemporaneous precipitation. We then explain the cause of precipitation underestimation from instrumental error caused by wind-induced gauge undercatch and the representativeness error caused by sparse-uneven gauge density and the complexity of local surface conditions. These findings require us to rethink previous results concerning the water cycle, prompting the study to discuss potential solutions.

8.
Proc Natl Acad Sci U S A ; 121(36): e2409955121, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39190351

RESUMEN

Facing complex and variable emerging antibiotic pollutants, the traditional development of functional materials is a "trial-and-error" process based on physicochemical principles, where laborious steps and long timescales make it difficult to accelerate technical breakthroughs. Notably, natural biomolecular coronas derived from highly tolerant organisms under significant contamination scenarios can be used in conjunction with nanotechnology to tackling emerging contaminants of concern. Here, super worms (Tubifex tubifex) with high pollutant tolerance were integrated with nano-zero valent iron (nZVI) to effectively reduce the content of 17 antibiotics in wastewater within 7 d. Inspired by the synergistic remediation, nZVI-augmented worms were constructed as biological nanocomposites. Neither nZVI (0.3 to 3 g/L) nor worms (104 to 105 per liter) alone efficiently degraded florfenicol (FF, as a representative antibiotic), while their composite removed 87% of FF (3 µmol/L). Under antibiotic exposure, biomolecules secreted by worms formed a corona on and modified the nZVI particle surface, enabling the nano-bio interface greater functionality, including responsiveness, enrichment, and reduction. Mechanistically, FF exposure activated glucose-alanine cycle pathways that synthesize organic acids and amines as major metabolites, which were assembled into vesicles and secreted, thereby interacting with nZVI in a biologically response design strategy. Lactic acid and urea formed hydrogen bonds with FF, enriched analyte presence at the heterogeneous interface. Succinic and lactic acids corroded the nZVI passivation layer and promoted electron transfer through surface conjugation. This unique strategy highlights biomolecular coronas as a complex resource to augment nano-enabled technologies and will provide shortcuts for rational manipulation of nanomaterial surfaces with coordinated multifunctionalities.


Asunto(s)
Antibacterianos , Hierro , Antibacterianos/química , Antibacterianos/farmacología , Animales , Hierro/química , Hierro/metabolismo , Corona de Proteínas/química , Corona de Proteínas/metabolismo , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/metabolismo , Oligoquetos/metabolismo , Biodegradación Ambiental , Restauración y Remediación Ambiental/métodos , Nanocompuestos/química
9.
Lancet ; 403(10445): 2720-2731, 2024 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-38824941

RESUMEN

BACKGROUND: Anti-PD-1 therapy and chemotherapy is a recommended first-line treatment for recurrent or metastatic nasopharyngeal carcinoma, but the role of PD-1 blockade remains unknown in patients with locoregionally advanced nasopharyngeal carcinoma. We assessed the addition of sintilimab, a PD-1 inhibitor, to standard chemoradiotherapy in this patient population. METHODS: This multicentre, open-label, parallel-group, randomised, controlled, phase 3 trial was conducted at nine hospitals in China. Adults aged 18-65 years with newly diagnosed high-risk non-metastatic stage III-IVa locoregionally advanced nasopharyngeal carcinoma (excluding T3-4N0 and T3N1) were eligible. Patients were randomly assigned (1:1) using blocks of four to receive gemcitabine and cisplatin induction chemotherapy followed by concurrent cisplatin radiotherapy (standard therapy group) or standard therapy with 200 mg sintilimab intravenously once every 3 weeks for 12 cycles (comprising three induction, three concurrent, and six adjuvant cycles to radiotherapy; sintilimab group). The primary endpoint was event-free survival from randomisation to disease recurrence (locoregional or distant) or death from any cause in the intention-to-treat population. Secondary endpoints included adverse events. This trial is registered with ClinicalTrials.gov (NCT03700476) and is now completed; follow-up is ongoing. FINDINGS: Between Dec 21, 2018, and March 31, 2020, 425 patients were enrolled and randomly assigned to the sintilimab (n=210) or standard therapy groups (n=215). At median follow-up of 41·9 months (IQR 38·0-44·8; 389 alive at primary data cutoff [Feb 28, 2023] and 366 [94%] had at least 36 months of follow-up), event-free survival was higher in the sintilimab group compared with the standard therapy group (36-month rates 86% [95% CI 81-90] vs 76% [70-81]; stratified hazard ratio 0·59 [0·38-0·92]; p=0·019). Grade 3-4 adverse events occurred in 155 (74%) in the sintilimab group versus 140 (65%) in the standard therapy group, with the most common being stomatitis (68 [33%] vs 64 [30%]), leukopenia (54 [26%] vs 48 [22%]), and neutropenia (50 [24%] vs 46 [21%]). Two (1%) patients died in the sintilimab group (both considered to be immune-related) and one (<1%) in the standard therapy group. Grade 3-4 immune-related adverse events occurred in 20 (10%) patients in the sintilimab group. INTERPRETATION: Addition of sintilimab to chemoradiotherapy improved event-free survival, albeit with higher but manageable adverse events. Longer follow-up is necessary to determine whether this regimen can be considered as the standard of care for patients with high-risk locoregionally advanced nasopharyngeal carcinoma. FUNDING: National Natural Science Foundation of China, Key-Area Research and Development Program of Guangdong Province, Natural Science Foundation of Guangdong Province, Overseas Expertise Introduction Project for Discipline Innovation, Guangzhou Municipal Health Commission, and Cancer Innovative Research Program of Sun Yat-sen University Cancer Center. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Quimioradioterapia , Quimioterapia de Inducción , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Humanos , Persona de Mediana Edad , Masculino , Femenino , Carcinoma Nasofaríngeo/terapia , Carcinoma Nasofaríngeo/tratamiento farmacológico , Adulto , China/epidemiología , Neoplasias Nasofaríngeas/tratamiento farmacológico , Neoplasias Nasofaríngeas/terapia , Quimioradioterapia/métodos , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticuerpos Monoclonales Humanizados/efectos adversos , Anticuerpos Monoclonales Humanizados/administración & dosificación , Anciano , Cisplatino/uso terapéutico , Cisplatino/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Gemcitabina , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapéutico , Desoxicitidina/administración & dosificación , Adulto Joven , Adolescente , Supervivencia sin Progresión
10.
Bioinformatics ; 40(7)2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38954836

RESUMEN

MOTIVATION: Accurately detecting pathogenic microorganisms requires effective primers and probe designs. Literature-derived primers are a valuable resource as they have been tested and proven effective in previous research. However, manually mining primers from published texts is time-consuming and limited in species scop. RESULTS: To address these challenges, we have developed MiPRIME, a real-time Microbial Primer Mining platform for primer/probe sequences extraction of pathogenic microorganisms with three highlights: (i) comprehensive integration. Covering >40 million articles and 548 942 organisms, the platform enables high-frequency microbial gene discovery from a global perspective, facilitating user-defined primer design and advancing microbial research. (ii) Using a BioBERT-based text mining model with 98.02% accuracy, greatly reducing information processing time. (iii) Using a primer ranking score, PRscore, for intelligent recommendation of species-specific primers. Overall, MiPRIME is a practical tool for primer mining in the pan-microbial field, saving time and cost of trial-and-error experiments. AVAILABILITY AND IMPLEMENTATION: The web is available at {{https://www.ai-bt.com}}.


Asunto(s)
Cartilla de ADN , Minería de Datos , Minería de Datos/métodos , Programas Informáticos , Bacterias/genética , Bacterias/clasificación
11.
Acc Chem Res ; 57(5): 763-775, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38386871

RESUMEN

ConspectusPolycyclic (hetero)aromatic hydrocarbons (PAHs) have emerged as a focal point in current interdisciplinary research, spanning the realms of chemistry, physics, and materials science. Possessing distinctive optical, electronic, and magnetic properties, these π-functional materials exhibit significant potential across diverse applications, including molecular electronic devices, organic spintronics, and biomedical functions, among others. Despite the extensive documentation of various PAHs over the decades, the efficient and precise synthesis of π-extended PAHs remains a formidable challenge, hindering their broader application. This challenge is primarily attributed to the intricate and often elusive nature of their synthesis, compounded by issues related to low solubility and unfavored stability.The development of π-building blocks that can be facilely and modularly transformed into diverse π-frameworks constitutes a potent strategy for the creation of novel PAH materials. For instance, based on the classic perylene diimide (PDI) unit, researchers such as Würthner, Wang, and Nuckolls have successfully synthesized a plethora of structurally diverse PAHs, as well as numerous other π-functional materials. However, until now the availability of such versatile building blocks is still severely limited, especially for those simultaneously having a facile preparation process, adequate solubilizing groups, favored material stability, and critically, rich possibilities for structural extension spaces.In this Account, we present an overview of our invention of a highly versatile bay-/ortho-octa-substituted perylene building block, designated as Per-4Br, for the construction of a series of novel PAH scaffolds with tailor-made structures and rich optoelectronic and magnetic properties. First, starting with a brief discussion of current challenges associated with the bottom-up synthesis of π-extended PAHs, we rationalize the key features of Per-4Br that enable facile access to new PAH molecules including its ease of large-scale preparation, favored material stability and solubility, and multiple flexible reaction sites, with a comparison to the PDI motif. Then, we showcase our rational design and sophisticated synthesis of a body of neutral or charged, closed- or open-shell, curved, or planar PAHs via controlled annulative π-extensions in different directions such as peripheral, diagonal, or multiple dimensions of the Per-4Br skeleton. In this part, the fundamental structure-property relationships between molecular conformations, electronic structures, and self-assembly behaviors of these PAHs and their unique physiochemical properties such as unusual open-shell ground states, global aromaticity, state-associated/stimuli-responsive magnetic activity, and charge transport characteristics will be emphatically elaborated. Finally, we offer our perspective on the continued advancement of π-functional materials based on Per-4Br, which, we posit, may stimulate heightened research interest in the versatile structural motifs typified by Per-4Br, consequently catalyzing further progress in the realm of organic π-functional materials.

12.
FASEB J ; 38(3): e23455, 2024 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-38308636

RESUMEN

Recent evidence suggests the anti-inflammatory effect of carrageenan oligosaccharides (COS). The effects of COS on intestinal injury induced by 0.6% sodium dodecyl sulfate (SDS) and the molecular mechanisms involved were investigated in this study. 0.625, 1.25, and 2.5 mg/mL COS in diet had no toxic effect in flies, and they could all prolong SDS-treated female flies' survival rate. 1.25 mg/mL COS prevented the development of inflammation by improving the intestinal barrier integrity and maintaining the intestinal morphology stability, inhibited the proliferation of intestine stem cells (ISCs), and the production of lysosomes induced by SDS, accompanied by a decrease in the expression of autophagy-related genes. Moreover, COS decreased the active oxygen species (ROS) content in gut and increased the antioxidant activity in SDS-induced female flies, while COS still played a role in increasing survival rate and decreasing intestinal leakage in CncC-RNAi flies. The improvement of anti-inflammation capacity may be associated with the regulation of intestinal microflora with COS supplementation for Drosophila melanogaster. COS changed the gut microbiota composition, and COS had no effect on germ-free (GF) flies. It is highlighted that COS could not work in Relish-RNAi flies, indicating relish is required for COS to perform beneficial effects. These results provide insights into the study of gut microbiota interacting with COS to modulate intestinal inflammation in specific hosts.


Asunto(s)
Drosophila melanogaster , Microbioma Gastrointestinal , Animales , Femenino , Carragenina/farmacología , Inflamación , Intestinos , Oligosacáridos/farmacología
13.
Mol Psychiatry ; 29(5): 1453-1464, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38321120

RESUMEN

Smell deficits and neurobiological changes in the olfactory bulb (OB) and olfactory epithelium (OE) have been observed in schizophrenia and related disorders. The OE is the most peripheral olfactory system located outside the cranium, and is connected with the brain via direct neuronal projections to the OB. Nevertheless, it is unknown whether and how a disturbance of the OE affects the OB in schizophrenia and related disorders. Addressing this gap would be the first step in studying the impact of OE pathology in the disease pathophysiology in the brain. In this cross-species study, we observed that chronic, local OE inflammation with a set of upregulated genes in an inducible olfactory inflammation (IOI) mouse model led to a volume reduction, layer structure changes, and alterations of neuron functionality in the OB. Furthermore, IOI model also displayed behavioral deficits relevant to negative symptoms (avolition) in parallel to smell deficits. In first episode psychosis (FEP) patients, we observed a significant alteration in immune/inflammation-related molecular signatures in olfactory neuronal cells (ONCs) enriched from biopsied OE and a significant reduction in the OB volume, compared with those of healthy controls (HC). The increased expression of immune/inflammation-related molecules in ONCs was significantly correlated to the OB volume reduction in FEP patients, but no correlation was found in HCs. Moreover, the increased expression of human orthologues of the IOI genes in ONCs was significantly correlated with the OB volume reduction in FEP, but not in HCs. Together, our study implies a potential mechanism of the OE-OB pathology in patients with psychotic disorders (schizophrenia and related disorders). We hope that this mechanism may have a cross-disease implication, including COVID-19-elicited mental conditions that include smell deficits.


Asunto(s)
Modelos Animales de Enfermedad , Inflamación , Bulbo Olfatorio , Mucosa Olfatoria , Trastornos Psicóticos , Esquizofrenia , Animales , Mucosa Olfatoria/patología , Mucosa Olfatoria/metabolismo , Trastornos Psicóticos/patología , Ratones , Humanos , Masculino , Inflamación/metabolismo , Inflamación/patología , Bulbo Olfatorio/patología , Bulbo Olfatorio/metabolismo , Femenino , Esquizofrenia/patología , Esquizofrenia/metabolismo , Esquizofrenia/fisiopatología , Esquizofrenia/genética , Trastornos del Olfato/etiología , Trastornos del Olfato/fisiopatología , Olfato/fisiología , Adulto , Ratones Endogámicos C57BL , Neuronas/metabolismo , Neuronas/patología
14.
Nature ; 569(7757): 537-541, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-31068693

RESUMEN

The discovery of the quantum Hall effect (QHE)1,2 in two-dimensional electronic systems has given topology a central role in condensed matter physics. Although the possibility of generalizing the QHE to three-dimensional (3D) electronic systems3,4 was proposed decades ago, it has not been demonstrated experimentally. Here we report the experimental realization of the 3D QHE in bulk zirconium pentatelluride (ZrTe5) crystals. We perform low-temperature electric-transport measurements on bulk ZrTe5 crystals under a magnetic field and achieve the extreme quantum limit, where only the lowest Landau level is occupied, at relatively low magnetic fields. In this regime, we observe a dissipationless longitudinal resistivity close to zero, accompanied by a well-developed Hall resistivity plateau proportional to half of the Fermi wavelength along the field direction. This response is the signature of the 3D QHE and strongly suggests a Fermi surface instability driven by enhanced interaction effects in the extreme quantum limit. By further increasing the magnetic field, both the longitudinal and Hall resistivity increase considerably and display a metal-insulator transition, which represents another magnetic-field-driven quantum phase transition. Our findings provide experimental evidence of the 3D QHE and a promising platform for further exploration of exotic quantum phases and transitions in 3D systems.

15.
Eur Heart J ; 45(18): 1662-1680, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38666340

RESUMEN

BACKGROUND AND AIMS: The Glu504Lys polymorphism in the aldehyde dehydrogenase 2 (ALDH2) gene is closely associated with myocardial ischaemia/reperfusion injury (I/RI). The effects of ALDH2 on neutrophil extracellular trap (NET) formation (i.e. NETosis) during I/RI remain unknown. This study aimed to investigate the role of ALDH2 in NETosis in the pathogenesis of myocardial I/RI. METHODS: The mouse model of myocardial I/RI was constructed on wild-type, ALDH2 knockout, peptidylarginine deiminase 4 (Pad4) knockout, and ALDH2/PAD4 double knockout mice. Overall, 308 ST-elevation myocardial infarction patients after primary percutaneous coronary intervention were enrolled in the study. RESULTS: Enhanced NETosis was observed in human neutrophils carrying the ALDH2 genetic mutation and ischaemic myocardium of ALDH2 knockout mice compared with controls. PAD4 knockout or treatment with NETosis-targeting drugs (GSK484, DNase1) substantially attenuated the extent of myocardial damage, particularly in ALDH2 knockout. Mechanistically, ALDH2 deficiency increased damage-associated molecular pattern release and susceptibility to NET-induced damage during myocardial I/RI. ALDH2 deficiency induced NOX2-dependent NETosis via upregulating the endoplasmic reticulum stress/microsomal glutathione S-transferase 2/leukotriene C4 (LTC4) pathway. The Food and Drug Administration-approved LTC4 receptor antagonist pranlukast ameliorated I/RI by inhibiting NETosis in both wild-type and ALDH2 knockout mice. Serum myeloperoxidase-DNA complex and LTC4 levels exhibited the predictive effect on adverse left ventricular remodelling at 6 months after primary percutaneous coronary intervention in ST-elevation myocardial infarction patients. CONCLUSIONS: ALDH2 deficiency exacerbates myocardial I/RI by promoting NETosis via the endoplasmic reticulum stress/microsomal glutathione S-transferase 2/LTC4/NOX2 pathway. This study hints at the role of NETosis in the pathogenesis of myocardial I/RI, and pranlukast might be a potential therapeutic option for attenuating I/RI, particularly in individuals with the ALDH2 mutation.


Asunto(s)
Aldehído Deshidrogenasa Mitocondrial , Trampas Extracelulares , Leucotrieno C4 , Daño por Reperfusión Miocárdica , Animales , Femenino , Humanos , Masculino , Ratones , Persona de Mediana Edad , Aldehído Deshidrogenasa Mitocondrial/genética , Aldehído Deshidrogenasa Mitocondrial/metabolismo , Benzamidas , Benzodioxoles , Modelos Animales de Enfermedad , Trampas Extracelulares/metabolismo , Antagonistas de Leucotrieno/farmacología , Antagonistas de Leucotrieno/uso terapéutico , Leucotrieno C4/antagonistas & inhibidores , Leucotrieno C4/metabolismo , Ratones Noqueados , Daño por Reperfusión Miocárdica/prevención & control , Daño por Reperfusión Miocárdica/genética , Daño por Reperfusión Miocárdica/metabolismo , Neutrófilos/metabolismo , Arginina Deiminasa Proteína-Tipo 4/metabolismo , Infarto del Miocardio con Elevación del ST/metabolismo
16.
Nano Lett ; 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38587481

RESUMEN

Unlocking the restricted interlayer carrier transfer in a two-dimensional perovskite is a crucial means to achieve the harmonization of efficiency and stability in perovskite solar cells. In this work, the effects of conjugated organic molecules on the interlayer carrier dynamics of 2D perovskites were investigated through nonadiabatic molecular dynamics simulations. We found that elongated conjugated organic cations contributed significantly to the accelerated interlayer carrier dynamics, originating from lowered transport barrier and boosted π-p coupling between organic and inorganic layers. Utilizing conjugated molecules of moderate length as spacer cations can yield both superior efficiency and exceptional stability simultaneously. However, conjugated chains that are too long lead to structural instability and stronger carrier recombination. The potential of conjugated chain-like molecules as spacer cations in 2D perovskites has been demonstrated in our work, offering valuable insights for the development of high-performance perovskite solar cells.

17.
Nano Lett ; 24(3): 881-889, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38198246

RESUMEN

Cellulose nanofiber (CNF) possesses excellent intrinsic properties, and many CNF-based high-performance structural and functional materials have been developed recently. However, the coordination of the mechanical properties and functionality is still a considerable challenge. Here, a CNF-based structural material is developed by a bioinspired gradient structure design using hollow magnetite nanoparticles and the phosphorylation-modified CNF as building blocks, which simultaneously achieves a superior mechanical performance and electromagnetic wave absorption (EMA) ability. Benefiting from the gradient design, the flexural strength of the structural material reached ∼205 MPa. Meanwhile, gradient design improves impedance matching, contributing to the high EMA ability (-59.5 dB) and wide effective absorption width (5.20 GHz). Besides, a low coefficient of thermal expansion and stable storage modulus was demonstrated as the temperature changes. The excellent mechanical, thermal, and EMA performance exhibited great potential for application in stealth equipment and electromagnetic interference protecting electronic packaging materials.

18.
J Neurosci ; 43(45): 7501-7510, 2023 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-37940584

RESUMEN

Smell loss has caught public attention during the recent COVID-19 pandemic. Research on olfactory function in health and disease gains new momentum. Smell deficits have long been recognized as an early clinical sign associated with neuropsychiatric disorders. Here we review research on the associations between olfactory deficits and neuropathological conditions, focusing on recent progress in four areas: (1) human clinical studies of the correlations between smell deficits and neuropsychiatric disorders; (2) development of olfactory mucosa-derived tissue and cell models for studying the molecular pathologic mechanisms; (3) recent findings in brain imaging studies of structural and functional connectivity changes in olfactory pathways in neuropsychiatric disorders; and (4) application of preclinical animal models to validate and extend the findings from human subjects. Together, these studies have provided strong evidence of the link between the olfactory system and neuropsychiatric disorders, highlighting the relevance of deepening our understanding of the role of the olfactory system in pathophysiological processes. Following the lead of studies reviewed here, future research in this field may open the door to the early detection of neuropsychiatric disorders, personalized treatment approaches, and potential therapeutic interventions through nasal administration techniques, such as nasal brush or nasal spray.


Asunto(s)
COVID-19 , Trastornos del Olfato , Humanos , Olfato/fisiología , Trastornos del Olfato/etiología , Pandemias , COVID-19/complicaciones , Mucosa Olfatoria
19.
Semin Cell Dev Biol ; 129: 22-30, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-34462249

RESUMEN

Olfactory dysfunction is often the earliest indicator of disease in a range of neurological and psychiatric disorders. One tempting working hypothesis is that pathological changes in the peripheral olfactory system where the body is exposed to many adverse environmental stressors may have a causal role for the brain alteration. Whether and how the peripheral pathology spreads to more central brain regions may be effectively studied in rodent models, and there is successful precedence in experimental models for Parkinson's disease. It is of interest to study whether a similar mechanism may underlie the pathology of psychiatric illnesses, such as schizophrenia. However, direct comparison between rodent models and humans includes challenges under light of comparative neuroanatomy and experimental methodologies used in these two distinct species. We believe that neuroimaging modality that has been the main methodology of human brain studies may be a useful viewpoint to address and fill the knowledge gap between rodents and humans in this scientific question. Accordingly, in the present review article, we focus on brain imaging studies associated with olfaction in healthy humans and patients with neurological and psychiatric disorders, and if available those in rodents. We organize this review article at three levels: 1) olfactory bulb (OB) and peripheral structures of the olfactory system, 2) primary olfactory cortical and subcortical regions, and 3) associated higher-order cortical regions. This research area is still underdeveloped, and we acknowledge that further validation with independent cohorts may be needed for many studies presented here, in particular those with human subjects. Nevertheless, whether and how peripheral olfactory disturbance impacts brain function is becoming even a hotter topic in the ongoing COVID-19 pandemic, given the risk of long-term changes of mental status associated with olfactory infection of SARS-CoV-2. Together, in this review article, we introduce this underdeveloped but important research area focusing on its implications in neurological and psychiatric disorders, with several pioneered publications.


Asunto(s)
COVID-19 , Trastornos del Olfato , Humanos , Neuroimagen/efectos adversos , Trastornos del Olfato/diagnóstico por imagen , Trastornos del Olfato/etiología , Trastornos del Olfato/patología , Bulbo Olfatorio/anatomía & histología , Bulbo Olfatorio/patología , Pandemias , SARS-CoV-2 , Olfato
20.
J Cell Mol Med ; 28(7): e18183, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38506078

RESUMEN

Mechanical stress is an internal force between various parts of an object that resists external factors and effects that cause an object to deform, and mechanical stress is essential for various tissues that are constantly subjected to mechanical loads to function normally. Integrins are a class of transmembrane heterodimeric glycoprotein receptors that are important target proteins for the action of mechanical stress stimuli on cells and can convert extracellular physical and mechanical signals into intracellular bioelectrical signals, thereby regulating osteogenesis and osteolysis. Integrins play a bidirectional regulatory role in bone metabolism. In this paper, relevant literature published in recent years is reviewed and summarized. The characteristics of integrins and mechanical stress are introduced, as well as the mechanisms underlying responses of integrin to mechanical stress stimulation. The paper focuses on integrin-mediated mechanical stress in different cells involved in bone metabolism and its associated signalling mechanisms. The purpose of this review is to provide a theoretical basis for the application of integrin-mediated mechanical stress to the field of bone tissue repair and regeneration.


Asunto(s)
Integrinas , Transducción de Señal , Integrinas/metabolismo , Estrés Mecánico , Transducción de Señal/fisiología , Células Cultivadas
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