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1.
Proc Natl Acad Sci U S A ; 120(51): e2312876120, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38085783

RESUMO

Electrochemical synthesis of valuable chemicals and feedstocks through carbon dioxide (CO2) reduction in acidic electrolytes can surmount the considerable CO2 loss in alkaline and neutral conditions. However, achieving high productivity, while operating steadily in acidic electrolytes, remains a big challenge owing to the severe competing hydrogen evolution reaction. Here, we show that vertically grown bismuth nanosheets on a gas-diffusion layer can create numerous cavities as electrolyte reservoirs, which confine in situ-generated hydroxide and potassium ions and limit inward proton diffusion, producing locally alkaline environments. Based on this design, we achieve formic acid Faradaic efficiency of 96.3% and partial current density of 471 mA cm-2 at pH 2. When operated in a slim continuous-flow electrolyzer, the system exhibits a full-cell formic acid energy efficiency of 40% and a single pass carbon efficiency of 79% and performs steadily over 50 h. We further demonstrate the production of pure formic acid aqueous solution with a concentration of 4.2 weight %.

2.
Am J Physiol Gastrointest Liver Physiol ; 327(4): G499-G512, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39104322

RESUMO

Apoptosis, inflammation, and wound healing are critical pathophysiological events associated with various liver diseases. Currently, there is a lack of in vivo approaches to study hepatocyte apoptosis-induced liver injury and repair. To address this critical knowledge gap, we developed a unique genetically modified mouse model, namely, 3-Transgene (Tg) with inducible Hepatocyte-Specific Apoptosis Phenotype (3xTg-iHAP) in this study. The 3xTg-iHAP mice possess three transgenes including Alb-Cre, Rosa26-rtTA, and tetO-Fasl on a B6 background. These mice are phenotypically normal, viable, and fertile. After subcutaneous administration of a single dose of doxycycline (5 mg/kg, Dox) to 3xTg-iHAP mice, we observed a complete histological spectrum of sterile liver wound-healing responses: asymptomatic hepatocyte apoptosis at 8 h, necrotic liver injury and sterile inflammation at 48 h, followed by hepatocyte mitosis and regeneration within 7 days. During the injury phase, the mice exhibited an increase in the biomarkers of alanine aminotransferase (ALT), chemokine (C-X-C motif) ligand 1 (CXCL1), and IL-6 in peripheral blood, as well as α-smooth muscle actin (α-SMA) protein in liver tissues. Conversely, the mice displayed a decrease in these markers in the recovery phase. Remarkably, this model shows that the sterile liver injury following elevated hepatocyte apoptosis is associated with an increase in myeloid cells in the liver. Within 7 days post-Dox administration, the liver of Dox-treated 3xTg-iHAP mice displays a normal histological structure, indicating the completion of wound healing. Together, we established a novel mouse model of injury and regeneration induced by hepatocyte apoptosis. This tool provides a robust in vivo platform for studying the pathophysiology of sterile liver inflammation, regeneration, and new therapeutic interventions for liver diseases.NEW & NOTEWORTHY Bu et al. present a triple-transgenic mouse model, namely, 3xTg-iHAP mice that are engineered to explore hepatocyte apoptosis-triggered sterile liver injury and regeneration. This model demonstrates a full spectrum of liver wound-healing responses from asymptomatic apoptosis to injury, myeloid cell-dominant sterile inflammation, and repair after induction of hepatocyte-specific apoptosis. The robust nature of this model makes it an invaluable in vivo tool for studying sterile liver inflammation, regeneration, and new therapeutic strategies.


Assuntos
Apoptose , Modelos Animais de Doenças , Hepatócitos , Regeneração Hepática , Camundongos Transgênicos , Células Mieloides , Animais , Hepatócitos/metabolismo , Hepatócitos/patologia , Camundongos , Células Mieloides/metabolismo , Fígado/metabolismo , Fígado/patologia , Cicatrização , Camundongos Endogâmicos C57BL , Quimiocina CXCL1/metabolismo , Quimiocina CXCL1/genética
3.
J Org Chem ; 89(11): 7859-7864, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38773955

RESUMO

Regioselective methods to access alkylated tetrazoles still remain a challenging goal. Herein, we describe a novel regioselective protocol for N2-arylation of tetrazoles with diazo compounds using inexpensive Al(OTf)3. This reaction could be conducted under mild conditions to access a diverse array of alkylated tetrazoles with 2-substituted tetrazoles as the major products, demonstrating a comprehensive range of substrate compatibility and excellent functional group compatibility. Mechanistic studies revealed a carbene-free process in this reaction procedure. Furthermore, the scale-up reaction and transformations of the N2-arylation of tetrazole products demonstrated the potential of this strategy.

4.
J Chem Inf Model ; 64(17): 6857-6865, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39246057

RESUMO

As a critical sensor protein, NLRP3 detects cellular perturbation caused by diverse exogenous and endogenous stimuli. NLRP3 activation requires domain rotation within the NEK7-bound NLRP3 monomer and assembly. However, a detailed molecular mechanism for NLRP3 assembly and activation remains elusive, particularly in terms of dynamics and energetics. In this work, all-atom molecular dynamics (MD) simulations are executed to describe large-amplitude closed-to-open conformational transitions along the rotational pathway. From the MD trajectories, the computed potential of mean force (PMF) shows that NLRP3 activation through monomeric domain rotation is an uphill process, during which the active conformation of the NLRP3-NEK7 monomer cannot be stabilized. Further binding free-energy calculations for two neighboring NLRP3-NEK7 subunits in a disc assembly with the C10 symmetry reveal that the protein self-assembly starts approximately at the 86.5° position on the rotary pathway, along which the NLRP3 activation becomes a downhill process to the active state at 90.5°. The active NLRP3-NEK7 monomeric conformation in the disc assembly is stabilized because of the interactions between the neighboring subunits, involving mainly FISNA loop 1 in one subunit and a "crocodile-clip" structure formed by the NBD helix-loop-strand motif (residues 351-373) and the WHD ß-hairpin loop (residues 501-521) in the other. Our simulations also demonstrate that NEK7 plays an important role in the NLRP3 cage dissociation in the centrosome, which is consistent with biological experiments. The computational results provide kinetic, energetic, and structural insights into the molecular mechanisms of the activation of NLRP3 and the NEK7-driven dissociation of inactive NLRP3 cages. The activation mechanism of NLRP3 proposed in this work is significantly different from those of previous structural studies.


Assuntos
Proteína 3 que Contém Domínio de Pirina da Família NLR , Humanos , Simulação de Dinâmica Molecular , Quinases Relacionadas a NIMA/metabolismo , Quinases Relacionadas a NIMA/química , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/química , Ligação Proteica , Conformação Proteica , Multimerização Proteica , Rotação , Termodinâmica
5.
J Environ Manage ; 369: 122243, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39213850

RESUMO

The accumulation of heavy metal(loid)s (HMs) in soil-grown mushrooms poses potential health risks. Morchella sextelata (black morel) is a typical soil-grown mushroom with a rapidly expanding cultivation area. This study investigated the distribution of arsenic, cadmium, chromium, copper, mercury, nickel, lead, and zinc in 213 pairs of soil and morel samples collected from 29 provincial administrative regions in China, together with the nutritional contents in the morel samples. The HM contents in the arable soils used to cultivate morels were 2.4-33.1 times higher than those in desert soils, while the HM contents in arable-soil morels were 2.9-155.9 times higher than desert morels. The HM contents of morels and their cultivation soils were significantly correlated (0.465 ≤ R ≤ 0.778, P < 0.001). Furthermore, the enrichment factors of most HMs were higher in arable soils than in desert soils (P < 0.05), except Hg. A considerable proportion of the arable soils produced morels with HMs exceeding the risk control standards (RCSs) for food and the health-risk thresholds of dietary intake. In comparison, HMs in morels from desert soils were far below the RCSs and health-risk thresholds. In addition, desert morels contained higher contents of crude proteins, total polysaccharides, and free amino acids (P < 0.001). These findings indicate that growing morels in desert soils is a way of green production that provides mushroom products with improved safety and nutrition.


Assuntos
Agricultura , Metais Pesados , Poluentes do Solo , Solo , Metais Pesados/análise , China , Solo/química , Poluentes do Solo/análise , Agaricales/química
6.
J Sci Food Agric ; 104(7): 3982-3991, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38252712

RESUMO

BACKGROUND: Many diseases may be caused by pathogens and oxidative stress resulting from carcinogens. Earlier studies have highlighted the antimicrobial and antioxidant effects of plant essential oils (EO). It is crucial to effectively utilize agricultural waste to achieve a sustainable agricultural economy and protect the environment. The present study aimed to evaluate the potential benefits of EO extracted from the discarded peels of Citrus depressa Hayata (CD) and Citrus microcarpa Bunge (CM), synonyms of Citrus deliciosa Ten and Citrus japonica Thunb, respectively. RESULTS: Gas chromatography-mass spectrometry analysis revealed that the main compounds in CD-EO were (R)-(+)-limonene (38.97%), γ-terpinene (24.39%) and linalool (6.22%), whereas, in CM-EO, the main compounds were (R)-(+)-limonene (48.00%), ß-pinene (13.60%) and γ-terpinene (12.07%). CD-EO exhibited inhibitory effects on the growth of common microorganisms, including Candida albicans, Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus. However, CM-EO showed only inhibitory effects on E. coli. Furthermore, CD-EO exhibited superior antioxidant potential, as demonstrated by its ability to eliminate 1,1-diphenyl-2-picrylhydrazyl and 2,2'-azinobis-3-ethylbenzthiazoline-6-sulfonate free radicals. Furthermore, CD-EO at a concentration of 100 µg mL-1 significantly inhibited 12-O-tetradecanoylphorbol-13-acetate-induced cancer transformation in mouse epidermal JB6 P+ cells (P < 0.05), possibly by up-regulating protein expression of nuclear factor erythroid 2-related factor 2 and its downstream antioxidant enzymes, such as NAD(P)H:quinone oxidoreductase 1, heme oxygenase-1 and UGT1A. CONCLUSION: These findings suggest that CD-EO exhibits inhibitory effects on pathogenic microorganisms, possesses antioxidant properties and has cancer chemopreventive potential. © 2024 Society of Chemical Industry.


Assuntos
Anti-Infecciosos , Citrus , Monoterpenos Cicloexânicos , Neoplasias , Óleos Voláteis , Animais , Camundongos , Óleos Voláteis/química , Antioxidantes/farmacologia , Antioxidantes/química , Limoneno/farmacologia , Citrus/química , Escherichia coli , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Óleos de Plantas/química
7.
J Am Chem Soc ; 145(31): 17485-17494, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37526148

RESUMO

Converting hydrogen chemical energy into electrical energy by fuel cells offers high efficiencies and environmental advantages, but ultrapure hydrogen (over 99.97%) is required; otherwise, the electrode catalysts, typically platinum on carbon (Pt/C), will be poisoned by impurity gases such as ammonia (NH3). Here we demonstrate remarkable NH3 resistivity over a nickel-molybdenum alloy (MoNi4) modulated by chromium (Cr) dopants. The resultant Cr-MoNi4 exhibits high activity toward alkaline hydrogen oxidation and can undergo 10,000 cycles without apparent activity decay in the presence of 2 ppm of NH3. Furthermore, a fuel cell assembled with this catalyst retains 95% of the initial peak power density even when NH3 (10 ppm)/H2 was fed, whereas the power output reduces to 61% of the initial value for the Pt/C catalyst. Experimental and theoretical studies reveal that the Cr modifier not only creates electron-rich states that restrain lone-pair electron donation but also downshifts the d-band center to suppress d-electron back-donation, synergistically weakening NH3 adsorption.

8.
Brief Bioinform ; 22(4)2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-33147626

RESUMO

Cell-cell communications in multicellular organisms generally involve secreted ligand-receptor (LR) interactions, which is vital for various biological phenomena. Recent advancements in single-cell RNA sequencing (scRNA-seq) have effectively resolved cellular phenotypic heterogeneity and the cell-type composition of complex tissues, facilitating the systematic investigation of cell-cell communications at single-cell resolution. However, assessment of chemical-signal-dependent cell-cell communication through scRNA-seq relies heavily on prior knowledge of LR interaction pairs. We constructed CellTalkDB (http://tcm.zju.edu.cn/celltalkdb), a manually curated comprehensive database of LR interaction pairs in humans and mice comprising 3398 human LR pairs and 2033 mouse LR pairs, through text mining and manual verification of known protein-protein interactions using the STRING database, with literature-supported evidence for each pair. Compared with SingleCellSignalR, the largest LR-pair resource, CellTalkDB includes not only 2033 mouse LR pairs but also 377 additional human LR pairs. In conclusion, the data on human and mouse LR pairs contained in CellTalkDB could help to further the inference and understanding of the LR-interaction-based cell-cell communications, which might provide new insights into the mechanism underlying biological processes.


Assuntos
Comunicação Celular , Bases de Dados Factuais , RNA-Seq , Receptores de Superfície Celular/metabolismo , Análise de Célula Única , Animais , Humanos , Ligantes , Camundongos
9.
Opt Express ; 31(10): 15697-15711, 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37157664

RESUMO

We study the multiple-photon bundle emission in the n-photon Jaynes-Cummings model composed of a two-level system coupled to a single-mode optical field via the n-photon exciting process. Here, the two-level system is strongly driven by a near-resonant monochromatic field, and hence the system can work in the Mollow regime, in which a super-Rabi oscillation between the zero-photon state and the n-photon state can take place under proper resonant conditions. We calculate the photon number populations and the standard equal-time high-order correlation functions, and find that the multiple-photon bundle emission can occur in this system. The multiple-photon bundle emission is also confirmed by investigating the quantum trajectories of the state populations and both the standard and generalized time-delay second-order correlation functions for multiple-photon bundle. Our work paves the way towards the study of multiple-photon quantum coherent devices, with potential application in quantum information sciences and technologies.

10.
Pediatr Res ; 93(3): 675-681, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35690685

RESUMO

BACKGROUND: The source and clearance of cytokines in the fetal circulation in term pregnancies complicated by chorioamnionitis remains unclear as are the contributions of placental transport, synthesis, and clearance. The objectives of the study were to determine (1) fetal and/or placental contributions to synthesis and/or clearance of inflammatory and anti-inflammatory cytokines in term pregnancies complicated by chorioamnionitis and (2) whether this differs in pregnancies further complicated by fetal hypoxia. METHODS: Prospective cohort study of pregnancies >37 weeks gestational age that included: Group 1, uncomplicated cesarean delivery without labor (n = 20); Group 2, uncomplicated vaginal delivery (n = 30); Group 3, pregnancies complicated by chorioamnionitis (n = 10); Group 4, complicated by chorioamnionitis + fetal hypoxia (n = 10). Umbilical arterial (UmA) and venous (UmV) blood were assayed for IL-1ß, IL-2, IL-6, IL-8, TNFα, and IL-10. RESULTS: IL-6 and IL-8 were below assay detection in UmA and UmV blood in Group 1 and increased in Group 2 (P < 0.01), UmA¼UmV (P < 0.01). Their concentrations increased further in Groups 3 and 4 (P = 0.003), UmA¼UmV. Placental clearance was concentration dependent that approaches saturation in the presence of chorioamnionitis. CONCLUSIONS: Marked increases in fetal synthesis of IL-6 and IL-8 occur in chorioamnionitis. Synthesis increase further when complicated by fetal hypoxia. Cytokine removal occurs via placental concentration-dependent mechanisms, potentially contributing to adverse fetal effects. IMPACT: The source and role of the placenta in synthesis and/or clearance of inflammatory mediators in term pregnancies complicated by clinical chorioamnionitis are unclear; however, conventional wisdom suggests the placenta is their source. This is the first study demonstrating that circulating concentrations of fetal IL-6 and IL-8 in clinical chorioamnionitis ± birth asphyxia in term pregnancies are of fetal origin. Circulating fetal inflammatory cytokines are cleared by concentration-dependent placental mechanisms that are nearly saturated in chorioamnionitis ± fetal hypoxia. These observations provide additional insight into understanding the fetal immune response in term pregnancies complicated by clinical chorioamnionitis.


Assuntos
Corioamnionite , Placenta , Recém-Nascido , Gravidez , Feminino , Humanos , Citocinas , Interleucina-6 , Hipóxia Fetal , Estudos Prospectivos , Interleucina-8
11.
J Appl Microbiol ; 134(12)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37960923

RESUMO

AIMS: This study aimed to investigate the inhibitory effect of tannic acid (TA) on the growth of Apiospora arundinis and 3-Nitropropionic acid (3-NPA) production. METHODS AND RESULTS: To investigate the antifungal mechanism, the effects of TA on the hypha growth, electrical conductivity, hypha morphology, defense-related enzymes, and 3-NPA production of A. arundinis were studied. TA concentrations of 640 and 1280 µg ml-1 exhibited strong antifungal activity against A. arundinis. The results of scanning electron microscopy and transmission electron microscopy showed that the hypha of the A. arundinis was severely deformed after TA treatment, and the cell membrane was blurred and thin, vacuoles were obviously shrunken and smaller, and most of the organelles were decomposed into irregular fragments. The increased electrical conductivity and malondialdehyde content indicated that TA caused peroxidation of unsaturated fatty acids and damaged the structure of the cell membrane. The decrease of intracellular ATPase and succinate dehydrogenase content indicated that TA damaged the function of mitochondria, and participated in the inhibition of respiratory metabolism. In addition, TA significantly reduced 3-NPA production and completely inhibited 3-NPA production at 640 and 1280 µg ml-1. CONCLUSION: TA effectively inhibited both growth of A. arundinis in vitro and 3-NPA production.


Assuntos
Antifúngicos , Mitocôndrias , Antifúngicos/farmacologia , Propionatos/farmacologia
12.
Nucleic Acids Res ; 49(21): e122, 2021 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-34500471

RESUMO

Advances in single-cell RNA sequencing (scRNA-seq) have furthered the simultaneous classification of thousands of cells in a single assay based on transcriptome profiling. In most analysis protocols, single-cell type annotation relies on marker genes or RNA-seq profiles, resulting in poor extrapolation. Still, the accurate cell-type annotation for single-cell transcriptomic data remains a great challenge. Here, we introduce scDeepSort (https://github.com/ZJUFanLab/scDeepSort), a pre-trained cell-type annotation tool for single-cell transcriptomics that uses a deep learning model with a weighted graph neural network (GNN). Using human and mouse scRNA-seq data resources, we demonstrate the high performance and robustness of scDeepSort in labeling 764 741 cells involving 56 human and 32 mouse tissues. Significantly, scDeepSort outperformed other known methods in annotating 76 external test datasets, reaching an 83.79% accuracy across 265 489 cells in humans and mice. Moreover, we demonstrate the universality of scDeepSort using more challenging datasets and using references from different scRNA-seq technology. Above all, scDeepSort is the first attempt to annotate cell types of scRNA-seq data with a pre-trained GNN model, which can realize the accurate cell-type annotation without additional references, i.e. markers or RNA-seq profiles.


Assuntos
Bases de Dados Genéticas , Aprendizado Profundo , RNA/metabolismo , Análise de Célula Única/métodos , Transcriptoma/genética , Animais , Humanos , Camundongos , Redes Neurais de Computação
13.
Sensors (Basel) ; 23(2)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36679697

RESUMO

High-quality measurements of air quality are the highest priority for understanding widespread air pollution. Visibility has been widely suggested to be a good alternative to PM2.5 concentration as a measure. In this study, the similarities and differences between visibility and PM2.5 measurements in China are checked and the results reveal the potential application of visibility observation to the study of air quality. Based on the quality-controlled PM2.5 and visibility data from 2016 to 2018, the nonparametric Spearman correlation coefficient (ρ) values between stations for PM2.5 and visibility-derived surface extinction coefficient (bext) decrease as the station distance (R) increases. Some relatively low ρ values (<0.4) occur in regions characterized by the lowest (background) levels of PM2.5 and bext values, for example, the Tibetan and Yungui Plateau. The relatively lower ρ for bext compared to PM2.5 is probably caused by the predefined maximum threshold of visibility measurements (generally 30 km). A significant correlation between PM2.5 and bext is derived in most stations and relatively larger ρ values are evident in eastern China (Northeast China excluded) and in winter (the national median ρ is 0.67). The abrupt changes in specific mass extinction efficiency (αext) imply a potentially large influence of alternation of visibility sensors or recalibrations on visibility measurements. The bext data are thereafter corrected by comparison to the reference measurements at the adjacent stations, which leads to a three-year quality assured of visibility and bext datasets.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Material Particulado/análise , Monitoramento Ambiental/métodos , Poluição do Ar/análise , Estações do Ano , China , Poluentes Atmosféricos/análise
14.
Zhongguo Zhong Yao Za Zhi ; 48(23): 6307-6314, 2023 Dec.
Artigo em Zh | MEDLINE | ID: mdl-38211987

RESUMO

Fel Ursi is a dried product obtained from the gallbladder of Ursidae animals, such as Selenarctos thibetanus or Ursus arctos, through gallbladder surgery for bile drainage. It is one of the rare animal medicinal materials in China and is known for its therapeutic effects, including clearing heat, removing toxins, extinguishing wind, relieving spasms, clearing the liver, and improving vision. Research has also found that Fel Ursi has pharmacological effects against cardiovascular and cerebrovascular diseases, such as anti-inflammatory, anti-apoptotic, and antioxidant stress properties. Recently, numerous studies have confirmed the close relationship between cardiovascular and cerebrovascular diseases and the gut microbiota as well as gut metabolites. Fel Ursi contains bile acid components that may have bidirectional regulatory effects on the gut microbiota and gut metabolites. This aspect could represent a potential therapeutic pathway for Fel Ursi in the treatment of cardiovascular and cerebrovascular diseases. This article comprehensively summarized relevant literature in China and abroad, reviewed the research progress on the pharmacological effects of Fel Ursi against cardiovascular and cerebrovascular diseases, and explored the impact of Fel Ursi on gut microbiota and gut metabolites, thereby aiming to provide references for further in-depth research and clinical application of Fel Ursi.


Assuntos
Doenças Cardiovasculares , Transtornos Cerebrovasculares , Ursidae , Animais , Transtornos Cerebrovasculares/tratamento farmacológico , Ácidos e Sais Biliares , Pulmão , Fígado , Doenças Cardiovasculares/tratamento farmacológico
15.
J Biol Chem ; 296: 100098, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33208462

RESUMO

The TP53 gene is the most frequently mutated gene in human cancers, and the majority of TP53 mutations are missense mutations. As a result, these mutant p53 (mutp53) either directly lose wildtype p53 (wtp53) tumor suppressor function or exhibit a dominant negative effect over wtp53. In addition, some mutp53 have acquired new oncogenic function (gain of function). Therefore, targeting mutp53 for its degradation may serve as a promising strategy for cancer prevention and therapy. Based on our previous finding that farnesylated DNAJA1 is a crucial chaperone in maintaining mutp53 stabilization, and by using an in silico approach, we built 3D homology models of human DNAJA1 and mutp53R175H proteins, identified the interacting pocket in the DNAJA1-mutp53R175H complex, and found one critical druggable small molecule binding site in the DNAJA1 glycine/phenylalanine-rich region. We confirmed that the interacting pocket in the DNAJA1-mutp53R175H complex was crucial for stabilizing mutp53R175H using a site-directed mutagenesis approach. We further screened a drug-like library to identify a promising small molecule hit (GY1-22) against the interacting pocket in the DNAJA1-mutp53R175H complex. The GY1-22 compound displayed an effective activity against the DNAJA1-mutp53R175H complex. Treatment with GY1-22 significantly reduced mutp53 protein levels, enhanced Waf1p21 expression, suppressed cyclin D1 expression, and inhibited mutp53-driven pancreatic cancer growth both in vitro and in vivo. Together, our results indicate that the interacting pocket in the DNAJA1-mutp53R175H complex is critical for mutp53's stability and oncogenic function, and DNAJA1 is a robust therapeutic target for developing the efficient small molecule inhibitors against oncogenic mutp53.


Assuntos
Proteínas de Choque Térmico HSP40/metabolismo , Mutação de Sentido Incorreto , Proteína Supressora de Tumor p53/metabolismo , Substituição de Aminoácidos , Animais , Linhagem Celular Tumoral , Inibidor de Quinase Dependente de Ciclina p21/biossíntese , Regulação da Expressão Gênica , Proteínas de Choque Térmico HSP40/genética , Humanos , Camundongos , Estabilidade Proteica , Proteína Supressora de Tumor p53/antagonistas & inibidores , Proteína Supressora de Tumor p53/genética
16.
Phys Rev Lett ; 129(6): 063602, 2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-36018654

RESUMO

Entanglement of light and multiple vibrations is a key resource for multichannel quantum information processing and memory. However, entanglement generation is generally suppressed, or even fully destroyed, by the dark-mode (DM) effect induced by the coupling of multiple degenerate or near-degenerate vibrational modes to a common optical mode. Here we propose how to generate optomechanical entanglement via DM breaking induced by synthetic magnetism. We find that at nonzero temperature, light and vibrations are separable in the DM-unbreaking regime but entangled in the DM-breaking regime. Remarkably, the threshold thermal phonon number for preserving entanglement in our simulations has been observed to be up to 3 orders of magnitude stronger than that in the DM-unbreaking regime. The application of the DM-breaking mechanism to optomechanical networks can make noise-tolerant entanglement networks feasible. These results are quite general and can initiate advances in quantum resources with immunity against both dark modes and thermal noise.

17.
Neurochem Res ; 47(12): 3697-3708, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35960484

RESUMO

Astrocytes act as "housekeeping cells" for maintaining cerebral homeostasis and play an important role in many disorders. Recent studies further highlight the contribution of autophagy to astrocytic functions, including astrogenesis, the astrocytic removal of neurotoxins or stressors, and astrocytic polarization. More importantly, genetic and pharmacological approaches have provided evidence that outlines the contributions of astrocytic autophagy to several brain disorders, including neurodegeneration, cerebral ischemia, and depression. In this study, we summarize the emerging role of autophagy in regulating astrocytic functions and discuss the contributions of astrocytic autophagy to different CNS disorders.


Assuntos
Astrócitos , Isquemia Encefálica , Humanos , Autofagia/fisiologia , Encéfalo
18.
Pathobiology ; 89(1): 1-12, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34535611

RESUMO

BACKGROUND: Anal squamous cell carcinoma (SCC) is a rare gastrointestinal malignancy with rising incidence, both in the United States and internationally. The primary risk factor for anal SCC is human papillomavirus (HPV) infection. However, there is a growing burden of disease in patients with human immunodeficiency virus (HIV) and HPV coinfection, with the incidence of anal SCC significantly increasing in this population. This is particularly true in HIV-infected men. The epidemiologic correlation between HIV-HPV coinfection and anal SCC is established; however, the immunologic mechanisms underlying this relationship are not well understood. SUMMARY: HIV-related immunosuppression due to low circulating CD4+ T cells is one component of increased risk, but other mechanisms, such as the effect of HIV on CD8+ T lymphocyte tumor infiltration and the PD-1/PD-L1 axis in antitumor and antiviral response, is emerging as significant contributors. The goal of this article is to review existing research on HIV-HPV coinfected anal SCC and precancerous lesions, propose explanations for the detrimental synergy of HIV and HPV on the pathogenesis and immunologic response to HPV-associated cancers, and discuss implications for future treatments and immunotherapies in HIV-positive patients with HPV-mediated anal SCC. Key Messages: The incidence of anal squamous cell carcinoma is increased in human immunodeficiency virus (HIV)-infected patients, even in patients on highly active antiretroviral therapy. Locoregional HIV infection may enhance human papillomavirus oncogenicity. Chronic inflammation due to HIV infection may contribute to CD8+ T lymphocyte exhaustion by upregulating PD-1 expression, thereby blunting cytotoxic antitumor response.


Assuntos
Alphapapillomavirus , Carcinoma de Células Escamosas , Infecções por HIV , Infecções por Papillomavirus , Carcinogênese , Infecções por HIV/complicações , Humanos , Masculino , Papillomaviridae , Infecções por Papillomavirus/complicações , Prevalência
19.
Pathobiology ; 89(4): 187-197, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35026755

RESUMO

BACKGROUND: Crohn's disease (CD) is a condition on the spectrum of inflammatory bowel disease that affects up to 20 people per 100,000 in the US annually, and with incidence increasing. One of the most significant sources of morbidity in CD is the formation of strictures, with resultant intestinal blockage a common indication for hospitalization and surgical intervention in these patients. The pathophysiology of stricture formation is not fully understood. However, the fibroplasia that leads to fibrostenotic stricture formation may have shared pathophysiology with IgG4-related fibrosis. SUMMARY: Initial intestinal inflammation recruits innate immune cells, such as neutrophils, that secrete IL-1ß and IL-23, which induces a type 17 CD4+ T-helper T-cell (Th17)-mediated adaptive immune response. These CD4+ Th17 T cells also contribute to inflammation by secreting proinflammatory cytokines such as IL-17 and IL-21. IL-21 recruits and stimulates CD4+ T follicular helper (Tfh) cells, which secrete more IL-21. This causes ectopic germinal center formation, recruiting and stimulating naïve B cells. The IL-17 and IL-21 produced by Th17 cells and Tfh cells also induce IgG4 plasmablast differentiation. Finally, these IgG4-producing plasmablasts secrete platelet-derived growth factor (PDGF), which activates local PDGF-receptor expressing fibroblasts and myofibroblasts, resulting in uncontrolled fibroplasia.


Assuntos
Doença de Crohn , Imunoglobulina G , Plasmócitos , Constrição Patológica , Humanos , Inflamação , Plasmócitos/imunologia , Células Th17
20.
Appl Opt ; 61(31): 9217-9224, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36607056

RESUMO

Fano resonance has an asymmetric and sharp resonance peak near the resonance wavelength, enhancing optical modulation performance. Here, a Fano resonant silicon optical modulator with a micro-ring resonator (MRR) coupled with a T-shaped waveguide is designed. Compared with an MRR modulator, a Fano resonance-based modulator has a smaller wavelength range of changes in optical intensity (from 0 a.u. to 1 a.u.). Under the condition of achieving the same light intensity change, Fano resonance only needs to shift the wavelength by 0.07 times compared with MRR. By optimizing the doping section and the Fano resonance line shape, the modulation depth of the Fano modulator is 12.44 dB, and an insertion loss of 0.41 dB is obtained. Moreover, it improves the modulation linearity. This modulator provides a new idea, to the best of our knowledge, for the single-cavity Fano resonance modulator.

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