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1.
Mol Cell ; 82(23): 4519-4536.e7, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36384137

RESUMEN

Nutrient sensing and damage sensing are two fundamental processes in living organisms. While hyperglycemia is frequently linked to diabetes-related vulnerability to microbial infection, how body glucose levels affect innate immune responses to microbial invasion is not fully understood. Here, we surprisingly found that viral infection led to a rapid and dramatic decrease in blood glucose levels in rodents, leading to robust AMPK activation. AMPK, once activated, directly phosphorylates TBK1 at S511, which triggers IRF3 recruitment and the assembly of MAVS or STING signalosomes. Consistently, ablation or inhibition of AMPK, knockin of TBK1-S511A, or increased glucose levels compromised nucleic acid sensing, while boosting AMPK-TBK1 cascade by AICAR or TBK1-S511E knockin improves antiviral immunity substantially in various animal models. Thus, we identify TBK1 as an AMPK substrate, reveal the molecular mechanism coupling a dual sensing of glucose and nuclei acids, and report its physiological necessity in antiviral defense.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Ácidos Nucleicos , Animales , Proteínas Quinasas Activadas por AMP/genética , Inmunidad Innata , Antivirales , Glucosa
2.
Nature ; 603(7899): 159-165, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35197629

RESUMEN

Metformin, the most prescribed antidiabetic medicine, has shown other benefits such as anti-ageing and anticancer effects1-4. For clinical doses of metformin, AMP-activated protein kinase (AMPK) has a major role in its mechanism of action4,5; however, the direct molecular target of metformin remains unknown. Here we show that clinically relevant concentrations of metformin inhibit the lysosomal proton pump v-ATPase, which is a central node for AMPK activation following glucose starvation6. We synthesize a photoactive metformin probe and identify PEN2, a subunit of γ-secretase7, as a binding partner of metformin with a dissociation constant at micromolar levels. Metformin-bound PEN2 forms a complex with ATP6AP1, a subunit of the v-ATPase8, which leads to the inhibition of v-ATPase and the activation of AMPK without effects on cellular AMP levels. Knockout of PEN2 or re-introduction of a PEN2 mutant that does not bind ATP6AP1 blunts AMPK activation. In vivo, liver-specific knockout of Pen2 abolishes metformin-mediated reduction of hepatic fat content, whereas intestine-specific knockout of Pen2 impairs its glucose-lowering effects. Furthermore, knockdown of pen-2 in Caenorhabditis elegans abrogates metformin-induced extension of lifespan. Together, these findings reveal that metformin binds PEN2 and initiates a signalling route that intersects, through ATP6AP1, the lysosomal glucose-sensing pathway for AMPK activation. This ensures that metformin exerts its therapeutic benefits in patients without substantial adverse effects.


Asunto(s)
Hipoglucemiantes , Metformina , ATPasas de Translocación de Protón Vacuolares , Proteínas Quinasas Activadas por AMP/metabolismo , Adenosina Trifosfatasas/metabolismo , Secretasas de la Proteína Precursora del Amiloide , Animales , Caenorhabditis elegans/metabolismo , Diabetes Mellitus/tratamiento farmacológico , Glucosa/metabolismo , Humanos , Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/metabolismo , Hipoglucemiantes/farmacología , Lisosomas/metabolismo , Proteínas de la Membrana , Metformina/agonistas , Metformina/metabolismo , Metformina/farmacología , ATPasas de Translocación de Protón Vacuolares/metabolismo
3.
EMBO J ; 42(20): e113743, 2023 10 16.
Artículo en Inglés | MEDLINE | ID: mdl-37661833

RESUMEN

Mitochondria play essential roles in cancer cell adaptation to hypoxia, but the underlying mechanisms remain elusive. Through mitochondrial proteomic profiling, we here find that the prolyl hydroxylase EglN1 (PHD2) accumulates on mitochondria under hypoxia. EglN1 substrate-binding region in the ß2ß3 loop is responsible for its mitochondrial translocation and contributes to breast tumor growth. Furthermore, we identify AMP-activated protein kinase alpha (AMPKα) as an EglN1 substrate on mitochondria. The EglN1-AMPKα interaction is essential for their mutual mitochondrial translocation. After EglN1 prolyl-hydroxylates AMPKα under normoxia, they rapidly dissociate following prolyl-hydroxylation, leading to their immediate release from mitochondria. In contrast, hypoxia results in constant EglN1-AMPKα interaction and their accumulation on mitochondria, leading to the formation of a Ca2+ /calmodulin-dependent protein kinase 2 (CaMKK2)-EglN1-AMPKα complex to activate AMPKα phosphorylation, ensuring metabolic homeostasis and breast tumor growth. Our findings identify EglN1 as an oxygen-sensitive metabolic checkpoint signaling hypoxic stress to mitochondria through its ß2ß3 loop region, suggesting a potential therapeutic target for breast cancer.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Neoplasias de la Mama , Femenino , Humanos , Proteínas Quinasas Activadas por AMP/metabolismo , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Hipoxia , Prolina Dioxigenasas del Factor Inducible por Hipoxia/genética , Prolina Dioxigenasas del Factor Inducible por Hipoxia/metabolismo , Mitocondrias/metabolismo , Proteómica
4.
Plant Cell ; 36(5): 1806-1828, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38339982

RESUMEN

Wood formation involves consecutive developmental steps, including cell division of vascular cambium, xylem cell expansion, secondary cell wall (SCW) deposition, and programmed cell death. In this study, we identified PagMYB31 as a coordinator regulating these processes in Populus alba × Populus glandulosa and built a PagMYB31-mediated transcriptional regulatory network. PagMYB31 mutation caused fewer layers of cambial cells, larger fusiform initials, ray initials, vessels, fiber and ray cells, and enhanced xylem cell SCW thickening, showing that PagMYB31 positively regulates cambial cell proliferation and negatively regulates xylem cell expansion and SCW biosynthesis. PagMYB31 repressed xylem cell expansion and SCW thickening through directly inhibiting wall-modifying enzyme genes and the transcription factor genes that activate the whole SCW biosynthetic program, respectively. In cambium, PagMYB31 could promote cambial activity through TRACHEARY ELEMENT DIFFERENTIATION INHIBITORY FACTOR (TDIF)/PHLOEM INTERCALATED WITH XYLEM (PXY) signaling by directly regulating CLAVATA3/ESR-RELATED (CLE) genes, and it could also directly activate WUSCHEL HOMEOBOX RELATED4 (PagWOX4), forming a feedforward regulation. We also observed that PagMYB31 could either promote cell proliferation through the MYB31-MYB72-WOX4 module or inhibit cambial activity through the MYB31-MYB72-VASCULAR CAMBIUM-RELATED MADS2 (VCM2)/PIN-FORMED5 (PIN5) modules, suggesting its role in maintaining the homeostasis of vascular cambium. PagMYB31 could be a potential target to manipulate different developmental stages of wood formation.


Asunto(s)
Cámbium , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas , Populus , Factores de Transcripción , Xilema , Populus/genética , Populus/crecimiento & desarrollo , Populus/metabolismo , Xilema/metabolismo , Xilema/genética , Xilema/crecimiento & desarrollo , Cámbium/genética , Cámbium/crecimiento & desarrollo , Cámbium/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Pared Celular/metabolismo , Proliferación Celular , Madera/crecimiento & desarrollo , Madera/metabolismo , Madera/genética
5.
EMBO J ; 41(14): e109777, 2022 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-35670107

RESUMEN

Autophagy represents a fundamental mechanism for maintaining cell survival and tissue homeostasis in response to physiological and pathological stress. Autophagy initiation converges on the FIP200-ATG13-ULK1 complex wherein the serine/threonine kinase ULK1 plays a central role. Here, we reveal that the E3 ubiquitin ligase TRIM27 functions as a negative regulatory component of the FIP200-ATG13-ULK1 complex. TRIM27 directly polyubiquitinates ULK1 at K568 and K571 sites with K48-linked ubiquitin chains, with proteasomal turnover maintaining control over basal ULK1 levels. However, during starvation-induced autophagy, TRIM27 catalyzes non-degradative K6- and K11-linked ubiquitination of the serine/threonine kinase 38-like (STK38L) kinase. In turn, STK38L ubiquitination promotes its activation and phosphorylation of ULK1 at Ser495, rendering ULK1 in a permissive state for TRIM27-mediated hyper-ubiquitination of ULK1. This cooperative mechanism serves to restrain the amplitude and duration of autophagy. Further evidence from mouse models shows that basal autophagy levels are increased in Trim27 knockout mice and that Trim27 differentially regulates tumorigenesis and metastasis. Our study identifies a key role of STK38L-TRIM27-ULK1 signaling axis in negatively controlling autophagy with relevance established in human breast cancer.


Asunto(s)
Autofagia , Proteínas Serina-Treonina Quinasas , Animales , Homólogo de la Proteína 1 Relacionada con la Autofagia/genética , Carcinogénesis/genética , Proteínas de Unión al ADN , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , Ratones , Proteínas Nucleares , Proteínas Serina-Treonina Quinasas/genética , Serina , Factores de Transcripción , Ubiquitina-Proteína Ligasas
6.
Genes Dev ; 32(19-20): 1332-1343, 2018 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-30254107

RESUMEN

Plants have evolved complex photoreceptor-controlled mechanisms to sense and respond to seasonal changes in day length. This ability allows plants to optimally time the transition from vegetative growth to flowering. UV-B is an important part intrinsic to sunlight; however, whether and how it affects photoperiodic flowering has remained elusive. Here, we report that, in the presence of UV-B, genetic mutation of REPRESSOR OF UV-B PHOTOMORPHOGENESIS 2 (RUP2) renders the facultative long day plant Arabidopsis thaliana a day-neutral plant and that this phenotype is dependent on the UV RESISTANCE LOCUS 8 (UVR8) UV-B photoreceptor. We provide evidence that the floral repression activity of RUP2 involves direct interaction with CONSTANS, repression of this key activator of flowering, and suppression of FLOWERING LOCUS T transcription. RUP2 therefore functions as an essential repressor of UVR8-mediated induction of flowering under noninductive short day conditions and thus provides a crucial mechanism of photoperiodic flowering control.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/fisiología , Proteínas Cromosómicas no Histona/metabolismo , Flores/crecimiento & desarrollo , Fotoperiodo , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Unión al ADN/metabolismo , Regiones Promotoras Genéticas , Factores de Transcripción/metabolismo , Rayos Ultravioleta
7.
Plant Physiol ; 194(3): 1563-1576, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-37956407

RESUMEN

Photoperiodic plants coordinate the timing of flowering with seasonal light cues, thereby optimizing their sexual reproductive success. The WD40-repeat protein REPRESSOR OF UV-B PHOTOMORPHOGENESIS 2 (RUP2) functions as a potent repressor of UV RESISTANCE LOCUS 8 (UVR8) photoreceptor-mediated UV-B induction of flowering under noninductive, short-day conditions in Arabidopsis (Arabidopsis thaliana); however, in contrast, the closely related RUP1 seems to play no major role. Here, analysis of chimeric ProRUP1:RUP2 and ProRUP2:RUP1 expression lines suggested that the distinct functions of RUP1 and RUP2 in repressing flowering are due to differences in both their coding and regulatory DNA sequences. Artificial altered expression using tissue-specific promoters indicated that RUP2 functions in repressing flowering when expressed in mesophyll and phloem companion cells, whereas RUP1 functions only when expressed in phloem companion cells. Endogenous RUP1 expression in vascular tissue was quantified as lower than that of RUP2, likely underlying the functional difference between RUP1 and RUP2 in repressing flowering. Taken together, our findings highlight the importance of phloem vasculature expression of RUP2 in repressing flowering under short days and identify a basis for the functional divergence of Arabidopsis RUP1 and RUP2 in regulating flowering time.


Asunto(s)
Arabidopsis , Arabidopsis/genética , Reproducción , Señales (Psicología) , Floema/genética , Regiones Promotoras Genéticas/genética
8.
Mol Psychiatry ; 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38532012

RESUMEN

Immunopsychiatric field has rapidly accumulated evidence demonstrating the involvement of both innate and adaptive immune components in psychotic disorders such as schizophrenia. Nevertheless, researchers are facing dilemmas of discrepant findings of immunophenotypes both outside and inside the brains of psychotic patients, as discovered by recent meta-analyses. These discrepancies make interpretations and interrogations on their roles in psychosis remain vague and even controversial, regarding whether certain immune cells are more activated or less so, and whether they are causal or consequential, or beneficial or harmful for psychosis. Addressing these issues for psychosis is not at all trivial, as immune cells either outside or inside the brain are an enormously heterogeneous and plastic cell population, falling into a vast range of lineages and subgroups, and functioning differently and malleably in context-dependent manners. This review aims to overview the currently known immunophenotypes of patients with psychosis, and provocatively suggest the premature immune "burnout" or inflamm-aging initiated since organ development as a potential primary mechanism behind these immunophenotypes and the pathogenesis of psychotic disorders.

9.
Nature ; 568(7750): 108-111, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30918404

RESUMEN

Ethane is the second most abundant component of natural gas in addition to methane, and-similar to methane-is chemically unreactive. The biological consumption of ethane under anoxic conditions was suggested by geochemical profiles at marine hydrocarbon seeps1-3, and through ethane-dependent sulfate reduction in slurries4-7. Nevertheless, the microorganisms and reactions that catalyse this process have to date remained unknown8. Here we describe ethane-oxidizing archaea that were obtained by specific enrichment over ten years, and analyse these archaea using phylogeny-based fluorescence analyses, proteogenomics and metabolite studies. The co-culture, which oxidized ethane completely while reducing sulfate to sulfide, was dominated by an archaeon that we name 'Candidatus Argoarchaeum ethanivorans'; other members were sulfate-reducing Deltaproteobacteria. The genome of Ca. Argoarchaeum contains all of the genes that are necessary for a functional methyl-coenzyme M reductase, and all subunits were detected in protein extracts. Accordingly, ethyl-coenzyme M (ethyl-CoM) was identified as an intermediate by liquid chromatography-tandem mass spectrometry. This indicated that Ca. Argoarchaeum initiates ethane oxidation by ethyl-CoM formation, analogous to the recently described butane activation by 'Candidatus Syntrophoarchaeum'9. Proteogenomics further suggests that oxidation of intermediary acetyl-CoA to CO2 occurs through the oxidative Wood-Ljungdahl pathway. The identification of an archaeon that uses ethane (C2H6) fills a gap in our knowledge of microorganisms that specifically oxidize members of the homologous alkane series (CnH2n+2) without oxygen. Detection of phylogenetic and functional gene markers related to those of Ca. Argoarchaeum at deep-sea gas seeps10-12 suggests that archaea that are able to oxidize ethane through ethyl-CoM are widespread members of the local communities fostered by venting gaseous alkanes around these seeps.


Asunto(s)
Organismos Acuáticos/metabolismo , Archaea/metabolismo , Etano/metabolismo , Anaerobiosis , Archaea/clasificación , Archaea/enzimología , Archaea/genética , Deltaproteobacteria/metabolismo , Etano/química , Gases/química , Gases/metabolismo , Golfo de México , Metano/biosíntesis , Oxidación-Reducción , Oxidorreductasas/genética , Oxidorreductasas/aislamiento & purificación , Oxidorreductasas/metabolismo , Filogenia , ARN Ribosómico 16S/genética , Sulfatos/metabolismo , Sulfuros/metabolismo
10.
Genomics ; 116(3): 110832, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38518898

RESUMEN

GCN2-eIF2α signaling pathway plays crucial roles in cell growth,development, and protein synthesis. However, in polyploid fish, the function of this pathway is rarely understood. In this study, genes associated with the GCN2-eIF2α pathway (pkr, pek, gcn2, eif2α) are founded lower expression levels in the triploid crucian carp (3nCC) muscle compared to that of the red crucian carp (RCC). In muscle effect stage embryos of the 3nCC, the mRNA levels of this pathway genes are generally lower than those of RCC, excluding hri and fgf21. Inhibiting gcn2 in 3nCC embryos downregulates downstream gene expression (eif2α, atf4, fgf21), accelerating embryonic development. In contrast, overexpressing of eif2α can alter the expression levels of downstream genes (atf4 and fgf21), and decelerates the embryonic development. These results demonstrate the GCN2-eIF2α pathway's regulatory impact on 3nCC growth, advancing understanding of fish rapid growth genetics and offering useful molecular markers for breeding of excellent strains.


Asunto(s)
Carpas , Factor 2 Eucariótico de Iniciación , Proteínas de Peces , Transducción de Señal , Animales , Carpas/genética , Carpas/metabolismo , Carpas/crecimiento & desarrollo , Factor 2 Eucariótico de Iniciación/metabolismo , Factor 2 Eucariótico de Iniciación/genética , Proteínas de Peces/genética , Proteínas de Peces/metabolismo , Triploidía , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Factor de Transcripción Activador 4/metabolismo , Factor de Transcripción Activador 4/genética , Regulación del Desarrollo de la Expresión Génica , Desarrollo Embrionario/genética
11.
Nano Lett ; 24(21): 6210-6217, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38709107

RESUMEN

The spin-orbit coupling (SOC), the dynamics of the nonequilibrium transport process, and the breaking of time-reversal and space-inversion symmetries have been regarded as key factors for the emergence of chirality-induced spin selectivity (CISS) and chirality-dependent spin currents in helix molecules. In this work, we demonstrated the generation of persistent CISS currents in various circular single-stranded DNAs and 310-helix proteins for the first time, regardless of whether an external magnetic flux is applied or not. This new CISS effect presents only in equilibrium transport processes, distinct from the traditional CISS observed in nonequilibrium transport processes and linear helix molecules; we term it as the PCISS effect. Notably, PCISS manifests irrespective of whether the SOC is chirality-driven or stems from heavy-metal substrates, making it an efficient way to generate chirality-locked pure spin currents. Our research establishes a novel paradigm for examining the underlying physics of the CISS effect.

12.
Nano Lett ; 24(28): 8542-8549, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-38973706

RESUMEN

Aqueous aluminum-ion batteries (AAIBs) are considered a strong candidate for the new generation of energy storage devices. The lack of suitable cathode materials has been a bottleneck factor hindering the future development of AAIBs. In this work, we design and construct a highly effective cathode with dual morphologies. Two-dimensional (2D) layered MXene materials possessed good conductivity and hydrophilicity, which are used as the substrates to deposit rod-shaped vanadium oxides (V2O5) to form a three-dimensional (3D) cathode. The cathode design provides a strong boost for the rapid electrochemical activities of rod-shaped V2O5 by embedding/extracting both protons (H+) and aluminum-ion (Al3+). As a result, the V2O5@MXene cathode based AAIB delivers an ultrahigh initial specific capacity of 626 mAh/g at 0.1 A/g with a stable cycle performance up to 100 cycles. This work is a breakthrough for the development of cathode materials for AAIBs.

13.
Mol Med ; 30(1): 72, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38822247

RESUMEN

BACKGROUND: 8-Oxoguanine DNA glycosylase (OGG1), a well-known DNA repair enzyme, has been demonstrated to promote lung fibrosis, while the specific regulatory mechanism of OGG1 during pulmonary fibrosis remains unclarified. METHODS: A bleomycin (BLM)-induced mouse pulmonary fibrosis model was established, and TH5487 (the small molecule OGG1 inhibitor) and Mitochondrial division inhibitor 1 (Mdivi-1) were used for administration. Histopathological injury of the lung tissues was assessed. The profibrotic factors and oxidative stress-related factors were examined using the commercial kits. Western blot was used to examine protein expression and immunofluorescence analysis was conducted to assess macrophages polarization and autophagy. The conditional medium from M2 macrophages was harvested and added to HFL-1 cells for culture to simulate the immune microenvironment around fibroblasts during pulmonary fibrosis. Subsequently, the loss- and gain-of function experiments were conducted to further confirm the molecular mechanism of OGG1/PINK1. RESULTS: In BLM-induced pulmonary fibrosis, OGG1 was upregulated while PINK1/Parkin was downregulated. Macrophages were activated and polarized to M2 phenotype. TH5487 administration effectively mitigated pulmonary fibrosis, M2 macrophage polarization, oxidative stress and mitochondrial dysfunction while promoted PINK1/Parkin-mediated mitophagy in lung tissues of BLM-induced mice, which was partly hindered by Mdivi-1. PINK1 overexpression restricted M2 macrophages-induced oxidative stress, mitochondrial dysfunction and mitophagy inactivation in lung fibroblast cells, and OGG1 knockdown could promote PINK1/Parkin expression and alleviate M2 macrophages-induced mitochondrial dysfunction in HFL-1 cells. CONCLUSION: OGG1 inhibition protects against pulmonary fibrosis, which is partly via activating PINK1/Parkin-mediated mitophagy and retarding M2 macrophage polarization, providing a therapeutic target for pulmonary fibrosis.


Asunto(s)
Bleomicina , ADN Glicosilasas , Modelos Animales de Enfermedad , Macrófagos , Mitofagia , Proteínas Quinasas , Fibrosis Pulmonar , Animales , Mitofagia/efectos de los fármacos , Fibrosis Pulmonar/metabolismo , Fibrosis Pulmonar/inducido químicamente , Fibrosis Pulmonar/etiología , Fibrosis Pulmonar/patología , ADN Glicosilasas/metabolismo , ADN Glicosilasas/genética , Ratones , Macrófagos/metabolismo , Proteínas Quinasas/metabolismo , Bleomicina/efectos adversos , Masculino , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética , Estrés Oxidativo/efectos de los fármacos , Ratones Endogámicos C57BL , Activación de Macrófagos , Humanos , Quinazolinonas
14.
Anal Chem ; 96(26): 10860-10869, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38889184

RESUMEN

Single-molecule localization microscopy (SMLM) requires high-intensity laser irradiation, typically exceeding kW/cm2, to yield a sufficient photon count. However, this intense visible light exposure incurs substantial cellular toxicity, hindering its use in living cells. Here, we developed a class of near-infrared (NIR) spontaneously blinking fluorophores for SMLM. These NIR fluorophores are a combination of rhodamine spirolactams and merocyanine derivatives, where the rhodamine spirolactam component converts between a bright and dark state based on pH-dependent spirocyclization and merocyanine derivatives shift the excitation wavelength into the infrared. Single-molecule characterizations demonstrated their potential for SMLM. At a moderate power density of 3.93 kW/cm2, these probes exhibit duty cycle as low as 0.18% and an emission rate as high as 26,700 photons/s. Phototoxicity assessment under single-molecule imaging conditions reveals that NIR illumination (721 nm) minimizes harm to living cells. Employing these NIR fluorophores, we successfully captured time-lapse super-resolution tracking of mitochondria at a Fourier ring correlation (FRC) resolution of 69.4 nm and reconstructed the ultrastructures of endoplasmic reticulum (ER) in living cells.


Asunto(s)
Colorantes Fluorescentes , Rayos Infrarrojos , Colorantes Fluorescentes/química , Humanos , Células HeLa , Indoles/química , Rodaminas/química , Microscopía Fluorescente , Supervivencia Celular/efectos de los fármacos , Mitocondrias , Benzopiranos
15.
Am J Gastroenterol ; 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38526213

RESUMEN

INTRODUCTION: An optimal follow-up schedule for small (≤3-cm) hepatocellular carcinoma (HCC) after radiofrequency ablation (RFA) remains unclear in clinical guidelines. We aimed to assess the cost-effectiveness of follow-up strategies in patients with small HCC after RFA. METHODS: In total, 11,243 patients were collected from global institutions to calculate recurrence rates. Subsequently, a Markov model covering a 10-year period was developed to compare 25 surveillance strategies involving different surveillance techniques (computed tomography [CT], magnetic resonance imaging or ultrasonography [US], and α-fetoprotein [AFP]) and intervals (3 or 6 months). The study endpoint was incremental cost-effectiveness ratio (ICER), which represented additional cost per incremental quality-adjusted life year. Sensitivity analysis was conducted by varying the values of input parameters to observe the ICER. RESULTS: In a base case analysis, the dominant strategy was CT every 3 months during an initial 2 years, followed by semiannual CT, and then switch to biannual the combination of US screening and AFP testing after 5 years (m3_CT-m6_CT-m6_USAFP), with an ICER of $68,570.92 compared with the "not followed" strategy. One-way sensitivity analysis showed the ICER consistently remained below the willingness-to-pay threshold of $100,000.00. In a probabilistic sensitivity analysis, m3_CT-m6_CT-m6_USAFP was the most cost-effective approach in 95.6% of simulated scenarios at a willingness-to-pay threshold. DISCUSSION: For small HCC after RFA, the recommended follow-up strategy is CT, with scans scheduled every 3 months for the first 2 years, every 6 months thereafter, and transition to biannual the combination of US screening and AFP testing after 5 years.

16.
Small ; : e2400335, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38682593

RESUMEN

Aluminum batteries (ABs) are identified as one of the most promising candidates for the next generation of large-scale energy storage elements because of their efficient three-electron reaction. Compared to ionic electrolytes, aqueous aluminum-ion batteries (AAIBs) are considered safer, less costly, and more environmentally friendly. However, considerable cycling performance is a key issue limiting the development of AAIBs. Stable, efficient, and electrolyte-friendly cathodes are most desirable for AAIBs. Herein, a rod-shaped defect-rich α-MnO2 is designed as a cathode, which is capable to deliver high performance with stable cycling for 180 cycles at 500 mA g-1 and maintains a discharge specific capacity of ≈100 mAh g-1. In addition, the infiltrability simulation is effectively utilized to corroborate the rapid electrochemical reaction brought about by the defective mechanism. With the formation of oxygen vacancies, the dual embedding of protons and metal ions is activated. This work provides a brand-new design for the development and characterization of cathodes for AAIBs.

17.
Small ; : e2401314, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38644698

RESUMEN

Bismuth-based materials have been recognized as the appealing anodes for potassium-ion batteries (PIBs) due to their high theoretical capacity. However, the kinetics sluggishness and capacity decline induced by the structure distortion predominately retard their further development. Here, a heterostructure of polyaniline intercalated Bi2O2CO3/MXene (BOC-PA/MXene) hybrids is reported via simple self-assembly strategy. The ingenious design of heterointerface-rich architecture motivates significantly the interior self-built-in electric field (IEF) and high-density electron flow, thus accelerating the charge transfer and boosting ion diffusion. As a result, the hybrids realize a high reversible specific capacity, satisfying rate capability as well as long-term cycling stability. The in/ex situ characterizations further elucidate the stepwise intercalation-conversion-alloying reaction mechanism of BOC-PA/MXene. More encouragingly, the full cell investigation further highlights its competitive merits for practical application in further PIBs. The present work not only opens the way to the design of other electrodes with an appropriate working mechanism but also offers inspiration for built-in electric-field engineering toward high-performance energy storage devices.

18.
Small ; : e2400978, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38593307

RESUMEN

Lead (Pb) poisoning and CO2-induced global warming represent two exemplary environmental and energy issues threatening humanity. Various biomass-derived materials are reported to take up Pb and convert CO2 electrochemically into low-valent carbon species, but these works address the problems separately rather than settle the issues simultaneously. In this work, cheap, natural ellagic acid (EA) extracted from common plants is adopted to assemble a stable metal-organic framework (MOF), EA-Pb, by effective capture of Pb2+ ions in an aqueous medium (removal rate close to 99%). EA-Pb represents the first structurally well-defined Pb-based MOF showing selective electrocatalytic CO2-to-HCOO- conversion with Faradaic efficiency (FE) of 95.37% at -1.08 V versus RHE. The catalytic mechanism is studied by 13CO2 labeling, in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), and theoretical calculation. The use of EA-Pb as an electrocatalyst for CO2 reduction represents a 2-in-1 solution of converting detrimental wastes (Pb2+) as well as natural resources (EA) into wealth (electrocatalytic EA-Pb) for addressing the global warming issue.

19.
Opt Express ; 32(7): 11654-11664, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38571007

RESUMEN

The measurement accuracy of digital image correlation (DIC) is influenced by the quality of the speckle pattern. Although various models for generating random speckle patterns have been well discussed, obtaining appropriate speckle images with isotropic quality and performance could be a challenging issue in DIC. In this paper, we propose a novel (to our knowledge) method for generating speckle patterns based on modified Conway's game of life (GoL). By sequentially assembling the speckle patterns generated from the modified GoL, we produced the GoL speckle image. Then, verification and comparison experiments were conducted through pure in-plane translations. The results show that the generated speckle image which was resized with k s=6& k r=2 processing and subsequently fuzzified using a Gaussian filter, produces the best accuracy for DIC measurement. Furthermore, based on the rigid body in-plane rotation displacement tests in the physical experimental results of three different speckle images, the GoL speckle generated from our proposed method shows the smallest measurement error. This indicates that the proposed speckle patterns generating method could provide a new type of speckle pattern with better quality and accuracy.

20.
Opt Express ; 32(8): 13408-13418, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38859312

RESUMEN

Fiber optic hydrophones (FOHs) offer the notable advantage of electromagnetic interference resistance. Nevertheless, overcoming the challenge of sustaining stable, high-performance operation in intricate underwater settings at a low cost remains a considerable obstacle for them. To circumvent the restrictions noted above, we employed a miniaturized FOH, utilizing an easily fabricated extrinsic Fabry-Perot interferometer (EFPI) which is made up of a composite chromium-aluminum (Cr-Al) membrane and fiber. The linear demodulation also suppresses the drift issue in the output spectrum. The average sound pressure sensitivity of the sensor, according to experimental findings, is around -139.15 dB re 1 V/µPa, while the equivalent noise sound pressure at 1 kHz is 51.52 dB re 1 µPa/Hz1/2. This sensor has a lot of potential because of features like sensitive low-frequency response and noise performance.

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