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1.
Acc Chem Res ; 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38319810

RESUMEN

ConspectusLithium-sulfur (Li-S) batteries have attracted worldwide attention as promising next-generation rechargeable batteries due to their high theoretical energy density of 2600 Wh kg-1. The actual energy density of Li-S batteries at the pouch cell level has significantly exceeded that of state-of-the-art Li-ion batteries. However, the overall performances of Li-S batteries under practical working conditions are limited by the sluggish conversion kinetics of the sulfur cathodes. To overcome the above challenge, various kinetic promotion strategies have been proposed to accelerate the multiphase and multi-electron cathodic redox reactions between sulfur, lithium polysulfides (LiPSs), and lithium sulfide. Nowadays, kinetic promoters have been massively employed in sulfur cathodes to achieve Li-S batteries with high energy densities, high rates, and long lifespans. A comprehensive and timely summary of cutting-edge kinetic promoters for sulfur cathodes is of great essence to afford an in-depth understanding of the unique Li-S electrochemistry.In this Account, we outline the recent efforts on the design of sulfur cathode kinetic promoters for advanced Li-S batteries. The latest progress is discussed in detail regarding heterogeneous, homogeneous, and semi-immobilized kinetic promoters. Heterogeneous promoters, representatively known as electrocatalysts, function mainly by reducing the energy barriers of the interfacial electrochemical reactions. The working mechanism, activity regulation strategies, and reconstitution/deactivation processes of the heterogeneous promoters are reviewed to provide guiding principles for rational design. In comparison, homogeneous promoters are able to fully contact with the reaction interfaces and regulate the electron/ion-inaccessible reactants in working Li-S batteries. Redox mediators and redox comediators are typical homogeneous promoters. The former establishes extra chemical reaction pathways to circumvent the originally sluggish steps and boost the overall kinetics, while the latter fundamentally modifies the LiPS molecules to enhance their redox kinetics. For semi-immobilized promoters, the active units are generally anchored on the cathode substrate through flexible chains with mobile characteristics. Such a design endows the promoter with both heterogeneous and homogeneous characteristics to comprehensively regulate the multiphase sulfur redox reactions involving both mobile and immobile reactants.Overall, this Account summarizes the fundamental electrochemistry, design principles, and practical promotion effects of the various kinetic promoters used for the sulfur cathodes in Li-S batteries. We believe that this Account will provide an in-depth and cutting-edge understanding of the unique sulfur electrochemistry, thereby providing guidance for further development of high-performance Li-S batteries and analogous rechargeable battery systems.

2.
Proc Natl Acad Sci U S A ; 119(49): e2205013119, 2022 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-36442102

RESUMEN

Zika virus (ZIKV) targets the neural progenitor cells (NPCs) in brain during intrauterine infections and consequently causes severe neurological disorders, such as microcephaly in neonates. Although replicating in the cytoplasm, ZIKV dysregulates the expression of thousands of host genes, yet the detailed mechanism remains elusive. Herein, we report that ZIKV encodes a unique DNA-binding protein to regulate host gene transcription in the nucleus. We found that ZIKV NS5, the viral RNA polymerase, associates tightly with host chromatin DNA through its methyltransferase domain and this interaction could be specifically blocked by GTP. Further study showed that expression of ZIKV NS5 in human NPCs markedly suppressed the transcription of its target genes, especially the genes involved in neurogenesis. Mechanistically, ZIKV NS5 binds onto the gene body of its target genes and then blocks their transcriptional elongation. The utero electroporation in pregnant mice showed that NS5 expression significantly disrupts the neurogenesis by reducing the number of Sox2- and Tbr2-positive cells in the fetal cortex. Together, our findings demonstrate a molecular clue linking to the abnormal neurodevelopment caused by ZIKV infection and also provide intriguing insights into the interaction between the host cell and the pathogenic RNA virus, where the cytoplasmic RNA virus encodes a DNA-binding protein to control the transcription of host cell in the nuclei.


Asunto(s)
Infección por el Virus Zika , Virus Zika , Humanos , Femenino , Embarazo , Animales , Ratones , Cromatina/genética , Virus Zika/genética , Infección por el Virus Zika/genética , ADN , ARN Polimerasas Dirigidas por ADN/genética , Transcripción Genética
3.
J Am Chem Soc ; 146(15): 10812-10821, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38466658

RESUMEN

Aqueous electrolytes with a low voltage window (1.23 V) and prone side reactions, such as hydrogen evolution reaction and cathode dissolution, compromise the advantages of high safety and low cost of aqueous metal-ion batteries. Herein, introducing catechol (CAT) into the aqueous electrolyte, an outer sphere electron transfer mechanism is initiated to inhibit the water reactivity, achieving an electrochemical window of 3.24 V. In a typical Zn-ion battery, the outer sphere electrons jump from CAT to Zn2+-H2O at a geometrically favorable situation and between the solvation molecules without breaking or forming chemical bonds as that of the inner sphere electron transfers. The excited state π-π stacking further leads to the outer sphere electron transfer occurring at the electrolyte/electrode interface. This high-voltage electrolyte allows achieving an operating voltage two times higher than that of the usual aqueous electrolytes and provides almost the highest energy density and power density for the V2O5-based aqueous Zn-ion full batteries. The Zn//Zn symmetric battery delivers a 4000 h lifespan, and the Zn//V2O5 full battery achieves a ∼380 W h kg-1 energy density and a 92% capacity retention after 3000 cycles at 1 A g-1 and a 2.4 V output voltage. This outer sphere electron transfer strategy paves the way for designing high-voltage aqueous electrolytes.

4.
J Hepatol ; 81(2): 265-277, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38508240

RESUMEN

BACKGROUND & AIMS: Intrahepatic cholangiocarcinoma (iCCA) is the second most common primary liver cancer and is highly lethal. Clonorchis sinensis (C. sinensis) infection is an important risk factor for iCCA. Here we investigated the clinical impact and underlying molecular characteristics of C. sinensis infection-related iCCA. METHODS: We performed single-cell RNA sequencing, whole-exome sequencing, RNA sequencing, metabolomics and spatial transcriptomics in 251 patients with iCCA from three medical centers. Alterations in metabolism and the immune microenvironment of C. sinensis-related iCCAs were validated through an in vitro co-culture system and in a mouse model of iCCA. RESULTS: We revealed that C. sinensis infection was significantly associated with iCCA patients' overall survival and response to immunotherapy. Fatty acid biosynthesis and the expression of fatty acid synthase (FASN), a key enzyme catalyzing long-chain fatty acid synthesis, were significantly enriched in C. sinensis-related iCCAs. iCCA cell lines treated with excretory/secretory products of C. sinensis displayed elevated FASN and free fatty acids. The metabolic alteration of tumor cells was closely correlated with the enrichment of tumor-associated macrophage (TAM)-like macrophages and the impaired function of T cells, which led to formation of an immunosuppressive microenvironment and tumor progression. Spatial transcriptomics analysis revealed that malignant cells were in closer juxtaposition with TAM-like macrophages in C. sinensis-related iCCAs than non-C. sinensis-related iCCAs. Importantly, treatment with a FASN inhibitor significantly reversed the immunosuppressive microenvironment and enhanced anti-PD-1 efficacy in iCCA mouse models treated with excretory/secretory products from C. sinensis. CONCLUSIONS: We provide novel insights into metabolic alterations and the immune microenvironment in C. sinensis infection-related iCCAs. We also demonstrate that the combination of a FASN inhibitor with immunotherapy could be a promising strategy for the treatment of C. sinensis-related iCCAs. IMPACT AND IMPLICATIONS: Clonorchis sinensis (C. sinensis)-infected patients with intrahepatic cholangiocarcinoma (iCCA) have a worse prognosis and response to immunotherapy than non-C. sinensis-infected patients with iCCA. The underlying molecular characteristics of C. sinensis infection-related iCCAs remain unclear. Herein, we demonstrate that upregulation of FASN (fatty acid synthase) and free fatty acids in C. sinensis-related iCCAs leads to formation of an immunosuppressive microenvironment and tumor progression. Thus, administration of FASN inhibitors could significantly reverse the immunosuppressive microenvironment and further enhance the efficacy of anti-PD-1 against C. sinensis-related iCCAs.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , Clonorquiasis , Clonorchis sinensis , Ácidos Grasos , Microambiente Tumoral , Colangiocarcinoma/inmunología , Colangiocarcinoma/parasitología , Animales , Clonorchis sinensis/inmunología , Clonorchis sinensis/fisiología , Clonorquiasis/inmunología , Neoplasias de los Conductos Biliares/inmunología , Neoplasias de los Conductos Biliares/parasitología , Ratones , Microambiente Tumoral/inmunología , Humanos , Ácidos Grasos/metabolismo , Acido Graso Sintasa Tipo I/genética , Acido Graso Sintasa Tipo I/antagonistas & inhibidores , Acido Graso Sintasa Tipo I/metabolismo , Masculino , Femenino , Línea Celular Tumoral , Modelos Animales de Enfermedad , Macrófagos Asociados a Tumores/inmunología , Macrófagos Asociados a Tumores/metabolismo
5.
Microcirculation ; 31(5): e12854, 2024 07.
Artículo en Inglés | MEDLINE | ID: mdl-38690631

RESUMEN

OBJECTIVE: Designing physiologically adequate microvascular trees is of crucial relevance for bioengineering functional tissues and organs. Yet, currently available methods are poorly suited to replicate the morphological and topological heterogeneity of real microvascular trees because the parameters used to control tree generation are too simplistic to mimic results of the complex angiogenetic and structural adaptation processes in vivo. METHODS: We propose a method to overcome this limitation by integrating a conditional deep convolutional generative adversarial network (cDCGAN) with a local fractal dimension-oriented constrained constructive optimization (LFDO-CCO) strategy. The cDCGAN learns the patterns of real microvascular bifurcations allowing for their artificial replication. The LFDO-CCO strategy connects the generated bifurcations hierarchically to form microvascular trees with a vessel density corresponding to that observed in healthy tissues. RESULTS: The generated artificial microvascular trees are consistent with real microvascular trees regarding characteristics such as fractal dimension, vascular density, and coefficient of variation of diameter, length, and tortuosity. CONCLUSIONS: These results support the adoption of the proposed strategy for the generation of artificial microvascular trees in tissue engineering as well as for computational modeling and simulations of microcirculatory physiology.


Asunto(s)
Simulación por Computador , Microcirculación , Microvasos , Microvasos/fisiología , Microvasos/anatomía & histología , Humanos , Microcirculación/fisiología , Modelos Cardiovasculares , Fractales
6.
Small ; 20(31): e2309583, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38446095

RESUMEN

Triple-negative breast cancer (TNBC) is a highly heterogeneous subtype of breast cancer, characterized by aggressiveness and high recurrence rate. As monotherapy provides limited benefit to TNBC patients, combination therapy emerges as a promising treatment approach. Gambogic acid (GA) is an exceedingly promising anticancer agent. Nonetheless, its application potential is hampered by low drug loading efficiency and associated toxic side effects. To overcome these limitations, using mesoporous polydopamine (MPDA) endowed with photothermal conversion capabilities is considered as a delivery vehicle for GA. Meanwhile, GA can inhibit the activity of heat shock protein 90 (HSP90) to enhance the photothermal effect. Herein, GA-loaded MPDA nanoparticles (GA@MPDA NPs) are developed with a high drug loading rate of 75.96% and remarkable photothermal conversion performance. GA@MPDA NPs combined with photothermal treatment (PTT) significantly inhibit the tumor growth, and effectively trigger the immunogenic cell death (ICD), which thereby increase the number of activated effector T cells (CD8+ T cells and CD4+ T cells) in the tumor, and hoist the level of immune-inflammatory cytokines (IFN-γ, IL-6, and TNF-α). The above results suggest that the combination of GA@MPDA NPs with PTT expected to activate the antitumor immune response, thus potentially enhancing the clinical therapeutic effect on TNBC.


Asunto(s)
Indoles , Polímeros , Neoplasias de la Mama Triple Negativas , Xantonas , Xantonas/química , Xantonas/farmacología , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/patología , Indoles/química , Indoles/farmacología , Polímeros/química , Humanos , Animales , Línea Celular Tumoral , Femenino , Porosidad , Ratones , Nanopartículas/química
7.
J Transl Med ; 22(1): 805, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39215316

RESUMEN

Nicotinamide mononucleotide (NMN), a crucial intermediate in NAD + synthesis, can rapidly transform into NAD + within the body after ingestion. NMN plays a pivotal role in several important biological processes, including energy metabolism, cellular aging, circadian rhythm regulation, DNA repair, chromatin remodeling, immunity, and inflammation. NMN has emerged as a key focus of research in the fields of biomedicine, health care, and food science. Recent years have witnessed extensive preclinical studies on NMN, offering valuable insights into the pathogenesis of age- and aging-related diseases. Given the sustained global research interest in NMN and the substantial market expectations for the future, here, we comprehensively review the milestones in research on NMN biotherapy over the past 10 years. Additionally, we highlight the current research on NMN in the field of digestive system diseases, identifying existing problems and challenges in the field of NMN research. The overarching aim of this review is to provide references and insights for the further exploration of NMN within the spectrum of digestive system diseases.


Asunto(s)
Enfermedades del Sistema Digestivo , Humanos , Enfermedades del Sistema Digestivo/terapia , Animales , Terapia Biológica/métodos
8.
Respir Res ; 25(1): 160, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38600524

RESUMEN

BACKGROUND: No effective therapies for pulmonary fibrosis (PF) exist because of the unclear molecular pathogenesis and the lack of effective therapeutic targets. Zinc finger protein 451 (ZNF451), a transcriptional regulator, plays crucial roles in the pathogenesis of several diseases. However, its expression pattern and function in PF remain unknown. This study was designed to investigate the role of ZNF451 in the pathogenesis of lung fibrosis. METHODS: GEO dataset analysis, RT‒PCR, and immunoblot assays were used to examine the expression of ZNF451 in PF; ZNF451 knockout mice and ZNF451-overexpressing lentivirus were used to determine the importance of ZNF451 in PF progression; and migration assays, immunofluorescence staining, and RNA-seq analysis were used for mechanistic studies. RESULTS: ZNF451 is downregulated and negatively associated with disease severity in PF. Compared with wild-type (WT) mice, ZNF451 knockout mice exhibited much more serious PF changes. However, ZNF451 overexpression protects mice from BLM-induced pulmonary fibrosis. Mechanistically, ZNF451 downregulation triggers fibroblast activation by increasing the expression of PDGFB and subsequently activating PI3K/Akt signaling. CONCLUSION: These findings uncover a critical role of ZNF451 in PF progression and introduce a novel regulatory mechanism of ZNF451 in fibroblast activation. Our study suggests that ZNF451 serves as a potential therapeutic target for PF and that strategies aimed at increasing ZNF451 expression may be promising therapeutic approaches for PF.


Asunto(s)
Fibrosis Pulmonar , Animales , Ratones , Bleomicina/toxicidad , Fibroblastos/metabolismo , Pulmón/metabolismo , Ratones Noqueados , Fosfatidilinositol 3-Quinasas/metabolismo , Fibrosis Pulmonar/inducido químicamente , Fibrosis Pulmonar/genética , Fibrosis Pulmonar/metabolismo , Transducción de Señal
9.
Int J Behav Nutr Phys Act ; 21(1): 70, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38965619

RESUMEN

BACKGROUND: Dietary assessment methods have limitations in capturing real-time eating behaviour accurately. Equipped with automated dietary-data-collection capabilities, the "intelligent ordering system" (IOS) has potential applicability in obtaining long-term consecutive, relatively detailed on-campus dietary records among university students with little resource consumption. We investigated (1) the relative validity of IOS-derived nutrient/food intakes compared to those from the 7-day food diary (7DFD); (2) whether including a supplemental food frequency questionnaire (SFFQ) improves IOS accuracy; and (3) sex differences in IOS dietary intake estimation. METHODS: Medical students (n = 221; age = 22.2 ± 2.4 years; 38.5% male and 61.5% female) completed the 7DFD and SFFQ. During the consecutive 7-day survey period, students weighed and photographed each meal before and after consumption. Then, students reviewed their 3-month diet and completed the SFFQ, which includes eight underprovided school-canteen food items (e.g., dairy, fruits, nuts). Meanwhile, 9385 IOS dietary data entries were collected. We used Spearman coefficients and linear regression models to estimate the associations among the different dietary intake assessment methods. Individual- and group-level agreement was assessed using the Wilcoxon signed-rank test, cross-classification, and Bland‒Altman analysis. RESULTS: IOS mean daily energy, protein, fat, and carbohydrate intake estimations were significantly lower (-15-20%) than those of the 7DFD. The correlation coefficients varied from 0.52 (for added sugar) to 0.88 (for soybeans and nuts), with fruits (0.37) and dairy products (0.29) showing weaker correlations. Sixty-two (milk and dairy products) to 97% (soybeans and nuts) of participants were classified into the same or adjacent dietary intake distribution quartile using both methods. The energy and macronutrient intake differences between the IOS + SFFQ and 7DFD groups decreased substantially. The separate fruit intake measurements from each assessment method did not significantly differ from each other (p > 0.05). IOS and IOS + SFFQ regression models generally yielded higher R2 values for males than for females. CONCLUSION: Despite estimation differences, the IOS can be reliable for medical student dietary habit assessment. The SFFQ is useful for measuring consumption of foods that are typically unavailable in school cafeterias, improving the overall dietary evaluation accuracy. The IOS assessment was more accurate for males than for females.


Asunto(s)
Registros de Dieta , Dieta , Conducta Alimentaria , Estudiantes de Medicina , Humanos , Femenino , Masculino , Adulto Joven , Estudiantes de Medicina/estadística & datos numéricos , China , Universidades , Reproducibilidad de los Resultados , Facultades de Medicina , Encuestas y Cuestionarios , Ingestión de Energía , Evaluación Nutricional , Encuestas sobre Dietas/métodos , Adulto
10.
Psychiatry Clin Neurosci ; 78(4): 248-258, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38318694

RESUMEN

AIM: This study investigated the impact of an 8-month daily-guided intensive meditation-based intervention (iMI) on persistent hallucinations/delusions and health-related quality of life (QoL) in male inpatients with schizophrenia with treatment-refractory hallucinations and delusions (TRHDs). METHODS: A randomized controlled trial assigned 64 male inpatients with schizophrenia and TRHD equally to an 8-month iMI plus general rehabilitation program (GRP) or GRP alone. Assessments were conducted at baseline and the third and eighth months using the Positive and Negative Syndrome Scale (PANSS), 36-Item Short Form-36 (SF-36), and Five Facet Mindfulness Questionnaire (FFMQ). Primary outcomes measured PANSS reduction rates for total score, positive symptoms, and hallucinations/delusions items. Secondary outcomes assessed PANSS, SF-36, and FFMQ scores for psychotic symptoms, health-related QoL, and mindfulness skills, respectively. RESULTS: In the primary outcome, iMI significantly improved the reduction rates of PANSS total score, positive symptoms, and hallucination/delusion items compared with GRP at both the third and eighth months. Treatment response rates (≥25% reduction) for these measures significantly increased in the iMI group at the eighth month. Concerning secondary outcomes, iMI significantly reduced PANSS total score and hallucination/delusion items, while increasing scores in physical activity and mindfulness skills at both the third and eighth months compared with GRP. These effects were more pronounced with an 8-month intervention compared with a 3-month intervention. CONCLUSIONS: An iMI benefits patients with TRHDs by reducing persistent hallucinations/delusions and enhancing health-related QoL. Longer iMI duration yields superior treatment outcomes.


Asunto(s)
Meditación , Esquizofrenia , Humanos , Masculino , Esquizofrenia/complicaciones , Esquizofrenia/terapia , Deluciones/terapia , Calidad de Vida , Pacientes Internos , Alucinaciones/etiología , Alucinaciones/terapia
11.
Plant Dis ; 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39300849

RESUMEN

Wheat stripe rust (yellow rust), caused by Puccinia striiformis f. sp. tritici (Pst), is an important airborne disease worldwide. Pst inoculum strength in southern Henan in winter or early spring is important for spring epidemic in the main autumn-sown wheat-growing regions of China. However, there is limited knowledge about the source and time of initial infection on winter wheat in southern Henan. The first occurrence of wheat stripe rust in southern Henan was recorded annually from 2011-2022, from which we used the backward trajectory approach to infer the likely source of Pst inoculum responsible for the initial disease occurrence. The results suggested that the Pst inoculum responsible for initial rust established in the winter in southern Henan originated from the Gansu Pst oversummering area in China, whereas it originated from the adjacent winter Pst sporulation regions in southern Shaanxi and northwestern Hubei if Pst symptoms were first observed in early spring in southern Henan. Another possible Pst source is southern Hubei where Pst can also sporulate in the winter. Thus, early Pst development in winter in the main wheat production in China (Henan) is likely to be caused by Pst inoculum spread from the oversummering inocula or Pst epidemics in autumn seedlings in Gansu.

12.
Nano Lett ; 23(15): 7046-7053, 2023 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-37470490

RESUMEN

Selective electroreduction of CO2 to C1 feed gas provides an attractive avenue to store intermittent renewable energy. However, most of the CO2-to-CO catalysts are designed from the perspective of structural reconstruction, and it is challenging to precisely design a meaningful confining microenvironment for active sites on the support. Herein, we report a local sulfur doping method to precisely tune the electronic structure of an isolated asymmetric nickel-nitrogen-sulfur motif (Ni1-NSC). Our Ni1-NSC catalyst presents >99% faradaic efficiency for CO2-to-CO under a high current density of -320 mA cm-2. In situ attenuated total reflection surface-enhanced infrared absorption spectroscopy and differential electrochemical mass spectrometry indicated that the asymmetric sites show a significantly weaker binding strength of *CO and a lower kinetic overpotential for CO2-to-CO. Further theoretical analysis revealed that the enhanced CO2 reduction reaction performance of Ni1-NSC was mainly due to the effectively decreased intermediate activation energy.

13.
J Environ Manage ; 356: 120751, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38531131

RESUMEN

Cost-effective treatment or even valorization of the bauxite residue (red mud) from the alumina industry is in demand to improve their environmental and economic liabilities. This study proposes a strategy that provides a near-complete conversion of bauxite residue to valuable products. The first step involves dilute acid leaching, which allowed the fractionation of raw residues into (1) an aqueous fraction rich in silica and aluminium and (2) a solid residue rich in iron, titanium and rare earth elements. For the proposed process, 91% of the original silicon, 67% of the aluminium, 78% of the scandium and 69% of the cerium were recovered. The initial cost evaluation suggested that this approach is profitable with a gross margin of 167 $US per tonne. This "Residue2Product" approach should be considered for large-scale practices as one of the most economical and sustainable solutions to this environmental and economic liability for the alumina industry.


Asunto(s)
Óxido de Aluminio , Aluminio , Óxido de Aluminio/química , Hierro , Titanio , Agua
14.
Molecules ; 29(15)2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39125019

RESUMEN

Identifying the catalytic regioselectivity of enzymes remains a challenge. Compared to experimental trial-and-error approaches, computational methods like molecular dynamics simulations provide valuable insights into enzyme characteristics. However, the massive data generated by these simulations hinder the extraction of knowledge about enzyme catalytic mechanisms without adequate modeling techniques. Here, we propose a computational framework utilizing graph-based active learning from molecular dynamics to identify the regioselectivity of ginsenoside hydrolases (GHs), which selectively catalyze C6 or C20 positions to obtain rare deglycosylated bioactive compounds from Panax plants. Experimental results reveal that the dynamic-aware graph model can excellently distinguish GH regioselectivity with accuracy as high as 96-98% even when different enzyme-substrate systems exhibit similar dynamic behaviors. The active learning strategy equips our model to work robustly while reducing the reliance on dynamic data, indicating its capacity to mine sufficient knowledge from short multi-replica simulations. Moreover, the model's interpretability identified crucial residues and features associated with regioselectivity. Our findings contribute to the understanding of GH catalytic mechanisms and provide direct assistance for rational design to improve regioselectivity. We presented a general computational framework for modeling enzyme catalytic specificity from simulation data, paving the way for further integration of experimental and computational approaches in enzyme optimization and design.


Asunto(s)
Ginsenósidos , Simulación de Dinámica Molecular , Ginsenósidos/química , Ginsenósidos/metabolismo , Especificidad por Sustrato , Hidrolasas/química , Hidrolasas/metabolismo , Panax/química , Panax/enzimología
15.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(4): 420-424, 2024 Apr 15.
Artículo en Zh | MEDLINE | ID: mdl-38660908

RESUMEN

Spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disorder. With the emergence of disease-modifying therapies, the prognosis of SMA has significantly improved, drawing increased attention to the importance of home rehabilitation and nursing management. Long-term, standardized home rehabilitation and nursing can delay the progression of SMA, enhance the psychological well-being, and improve the quality of life of both patients and caregivers. This article provides an overview of the goals of home rehabilitation, basic functional training methods, respiratory management, and nutritional management for SMA patients, as well as psychological health issues, emphasizing the significance of obtaining appropriate home rehabilitation and support during the care process.


Asunto(s)
Atrofia Muscular Espinal , Humanos , Atrofia Muscular Espinal/rehabilitación , Atrofia Muscular Espinal/terapia , Servicios de Atención de Salud a Domicilio , Calidad de Vida
16.
J Am Chem Soc ; 145(17): 9718-9728, 2023 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-37084330

RESUMEN

Zeolite-supported metal nanocluster catalysts have attracted significant attention due to their broad application in heterogeneously catalyzed reactions. The preparation of highly dispersed metal catalysts commonly involves the use of organic compounds and requires the implementation of complicated procedures, which are neither green nor deployable at the large scale. Herein, we present a novel facile method (vacuum-heating) which employs a specific thermal vacuum processing protocol of catalysts to promote the decomposition of metal precursors. The removal of coordinated H2O via vacuum-heating restricts the formation of intermediates (metal-bound OH species), resulting in catalysts with a uniform, metal nanocluster distribution. The structure of the intermediate was determined by in situ Fourier transform infrared, temperature-programmed decomposition, and X-ray absorption spectroscopy (XAS) measurements. This alternative synthesis method is eco-friendly and cost-effective as the procedure occurs in the absence of organic compounds. It can be widely used for the preparation of catalysts from different metal species (Ni, Fe, Cu, Co, Zn) and precursors and is readily scaled-up.

17.
J Am Chem Soc ; 145(50): 27531-27538, 2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-38054906

RESUMEN

Single-atom catalysts exhibit promising electrocatalytic activity, a trait that can be further enhanced through the introduction of heteroatom doping within the carbon skeleton. Nonetheless, the intricate relationship between the doping positions and activity remains incompletely elucidated. This contribution sheds light on an inductive effect of single-atom sites, showcasing that the activity of the oxygen reduction reaction (ORR) can be augmented by reducing the spatial gap between the doped heteroatom and the single-atom sites. Drawing inspiration from this inductive effect, we propose a synthesis strategy involving ligand modification aimed at precisely adjusting the distance between dopants and single-atom sites. This precise synthesis leads to optimized electrocatalytic activity for the ORR. The resultant electrocatalyst, characterized by Fe-N3P1 single-atom sites, demonstrates remarkable ORR activity, thus exhibiting great potential in zinc-air batteries and fuel cells.

18.
Cancer Sci ; 114(6): 2265-2276, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36751987

RESUMEN

Programmed death ligand 1 (PD-L1) plays an important role in the occurrence of hepatocellular carcinoma (HCC). The present study indicated that epithelial-mesenchymal transition (EMT) and induction of cancer stem cell (CSC)-like properties contribute to metastasis of cancers. However, the molecular mechanisms underlying PD-L1 and EMT and CSC phenotypes in HCC remain to be elucidated. Here, we report that PD-L1 regulates not only EMT but also the stem-like transition in liver cancer cells. We observed high PD-L1 expression in CD133+ liver CSCs and CSC-enriched tumor spheres. Altering PD-L1 expression promoted liver CSC phenotypes by increasing the expression of stemness genes, the CD133+ cell population sizes, and the ability to form tumor spheres. Programmed death ligand 1 enhanced HCC cell tumorigenicity and invasion in nude mice. Additionally, PD-L1 overexpression in cells significantly increased cell motility and invasion, as well as the EMT process. Conversely, suppression of PD-L1 in cells had an opposite effect. Prolonged treatment of HCC cells with Akt inhibitor prefosine leads to activation of serum and glucocorticoid kinase 2 (SGK2) and rescued downregulation of PD-L1. Mechanistically, PD-L1 directly interacted with SGK2. Programmed death ligand 1 upregulated SGK2 and activated the SGK2/ß-catenin signaling pathway, and promoted EMT and CSC expansion in liver cancer cells, highlighting the role of SGK2 in PD-L1-mediated EMT and CSC phenotypes in liver cancer cells. In conclusion, our findings suggest that PD-L1 activated the SGK2/ß-catenin signaling pathway, to induce EMT and acquisition of a stem cell phenotype.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animales , Ratones , Antígeno B7-H1/metabolismo , beta Catenina/genética , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Transición Epitelial-Mesenquimal , Glucocorticoides/metabolismo , Glucocorticoides/farmacología , Neoplasias Hepáticas/patología , Ratones Desnudos , Células Madre Neoplásicas/metabolismo , Fenotipo , Transducción de Señal , Humanos
19.
Opt Express ; 31(26): 43821-43837, 2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-38178469

RESUMEN

We predicted peculiar ghost surface phonon polaritons in biaxially hyperbolic materials, where the two hyperbolic principal axes lie in the plane of propagation. We took the biaxially-hyperbolic α-MoO3 as one example of the materials to numerically simulate the ghost surface phonon polaritons. We found three unique ghost surface polaritons to appear in three enclosed wavenumber-frequency regions, respectively. These ghost surface phonon polaritons have different features from the surface phonon polaritons found previously, i.e., they are some hybrid-polarization surface waves composed of two coherent evanescent branch-waves in the α-MoO3 crystal. The interference of branch-waves leads to that their Poynting vector and electromagnetic fields both exhibit the oscillation-attenuation behavior along the surface normal, or a series of rapidly attenuated fringes. We found that the in-plane hyperbolic anisotropy and low-symmetric geometry of surface are the two necessary conditions for the existence of these ghost surface polaritons.

20.
Nutr Cancer ; 75(4): 1116-1122, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36856143

RESUMEN

BACKGROUND: Sarcopenia is a risk factor for poor cancer prognosis. Early identification and timely intervention of sarcopenia can improve patient prognosis. METHODS: A total of 91 patients with liver cirrhosis complicated with primary hepatocellular carcinoma were retrospectively analyzed. Based on the results of multivariable logistic regression analysis, a nomogram was developed. Moreover, 50 patients were enrolled for external validation. The predictive efficacy of the nomogram was evaluated using the receiver operating characteristic curve (ROC). RESULTS: According to the logistic regression analysis results, age, body mass index (BMI), creatinine-to-cystatin C ratio (Cre/CysC), and systemic immune inflammation index (SII) were independent risk factors of sarcopenia in patients with cirrhosis complicated with primary hepatocellular carcinoma (HCC) (all p < 0.05). The ABCS nomogram model was established, and the area under the ROC curve (AUC) was 0.896 (84.7% sensitivity, 81.2% specificity). The calibration curve of the nomogram was close to the ideal diagonal line. The predictive efficacy of the nomogram was verified through the external validation. CONCLUSION: The ABCS model based on SII and Cre/CysC can be used to identify high-risk sarcopenia in patients with cirrhosis complicated with HCC in the early stage.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Sarcopenia , Humanos , Carcinoma Hepatocelular/complicaciones , Carcinoma Hepatocelular/patología , Sarcopenia/complicaciones , Creatinina , Estudios Retrospectivos , Neoplasias Hepáticas/complicaciones , Neoplasias Hepáticas/patología , Cistatina C , Inflamación/complicaciones , Cirrosis Hepática/complicaciones
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