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1.
Proc Natl Acad Sci U S A ; 120(36): e2306512120, 2023 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-37639611

RESUMEN

Cells migrate by adapting their leading-edge behaviors to heterogeneous extracellular microenvironments (ECMs) during cancer invasions and immune responses. Yet it remains poorly understood how such complicated dynamic behaviors emerge from millisecond-scale assembling activities of protein molecules, which are hard to probe experimentally. To address this gap, we establish a spatiotemporal "resistance-adaptive propulsion" theory based on the interactions between Arp2/3 complexes and polymerizing actin filaments and a multiscale dynamic modeling system spanning from molecular proteins to the cell. We quantitatively find that cells can accurately self-adapt propulsive forces to overcome heterogeneous ECMs via a resistance-triggered positive feedback mechanism, dominated by polymerization-induced actin filament bending and the bending-regulated actin-Arp2/3 binding. However, for high resistance regions, resistance triggers a negative feedback, hindering branched filament assembly, which adapts cellular morphologies to circumnavigate the obstacles. Strikingly, the synergy of the two opposite feedbacks not only empowers the cell with both powerful and flexible migratory capabilities to deal with complex ECMs but also enables efficient utilization of intracellular proteins by the cell. In addition, we identify that the nature of cell migration velocity depending on ECM history stems from the inherent temporal hysteresis of cytoskeleton remodeling. We also show that directional cell migration is dictated by the competition between the local stiffness of ECMs and the local polymerizing rate of actin network caused by chemotactic cues. Our results reveal that it is the polymerization force-regulated actin filament-Arp2/3 complex binding interaction that dominates self-adaptive cell migrations in complex ECMs, and we provide a predictive theory and a spatiotemporal multiscale modeling system at the protein level.


Asunto(s)
Citoesqueleto de Actina , Actinas , Polimerizacion , Movimiento Celular , Citoesqueleto , Complejo 2-3 Proteico Relacionado con la Actina
2.
Proc Natl Acad Sci U S A ; 119(49): e2206159119, 2022 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-36442097

RESUMEN

Morphogenesis of active shells such as cells is a fundamental chemomechanical process that often exhibits three-dimensional (3D) large deformations and chemical pattern dynamics simultaneously. Here, we establish a chemomechanical active shell theory accounting for mechanical feedback and biochemical regulation to investigate the symmetry-breaking and 3D chiral morphodynamics emerging in the cell cortex. The active bending and stretching of the elastic shells are regulated by biochemical signals like actomyosin and RhoA, which, in turn, exert mechanical feedback on the biochemical events via deformation-dependent diffusion and inhibition. We show that active deformations can trigger chemomechanical bifurcations, yielding pulse spiral waves and global oscillations, which, with increasing mechanical feedback, give way to traveling or standing waves subsequently. Mechanical feedback is also found to contribute to stabilizing the polarity of emerging patterns, thus ensuring robust morphogenesis. Our results reproduce and unravel the experimentally observed solitary and multiple spiral patterns, which initiate asymmetric cleavage in Xenopus and starfish embryogenesis. This study underscores the crucial roles of mechanical feedback in cell development and also suggests a chemomechanical framework allowing for 3D large deformation and chemical signaling to explore complex morphogenesis in living shell-like structures.


Asunto(s)
Fenómenos Químicos , Citoesqueleto de Actina , Actomiosina , Diferenciación Celular , Química Física , Morfogénesis
3.
J Biol Chem ; 299(2): 102881, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36626986

RESUMEN

Mutations in genes involved in mitochondrial proline catabolism lead to the rare genetic disorder hyperprolinemia in humans. We have previously reported that mutations of proline catabolic genes in Caenorhabditis elegans impair mitochondrial homeostasis and shorten life span, and that these effects surprisingly occur in a diet type-dependent manner. Therefore, we speculated that a specific dietary component may mitigate the adverse effects of defective proline catabolism. Here, we discovered that high dietary glucose, which is generally detrimental to health, actually improves mitochondrial homeostasis and life span in C. elegans with faulty proline catabolism. Mechanistically, defective proline catabolism results in a shift of glucose catabolism toward the pentose phosphate pathway, which is crucial for cellular redox balance. This shift helps to maintain mitochondrial reactive oxygen species homeostasis and to extend life span, as suppression of the pentose phosphate pathway enzyme GSPD-1 prevents the favorable effects of high glucose. In addition, we demonstrate that this crosstalk between proline and glucose catabolism is mediated by the transcription factor DAF-16. Altogether, these findings suggest that a glucose-rich diet may be advantageous in certain situations and might represent a potentially viable treatment strategy for disorders involving impaired proline catabolism.


Asunto(s)
Caenorhabditis elegans , Glucosa , Longevidad , Animales , Humanos , Caenorhabditis elegans/efectos de los fármacos , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Glucosa/metabolismo , Glucosa/farmacología , Longevidad/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Prolina/metabolismo
4.
BMC Genomics ; 25(1): 693, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39009981

RESUMEN

ARs plays a crucial role in plant morphogenesis and development. The limited and inefficient rooting of scions poses a significant challenge to the efficiency and quality of clonal propagation of forest trees in silvicultural practices. Building on previous research conducted by our team, we found that applying IBA at a concentration of 1000 mg/L significantly enhanced mulberry rooting. This study aims to uncover the molecular mechanisms underlying this effect by analyzing RNA sequencing data from mulberry phloem before and after treatment with IBA over time intervals of 10, 20, 30, and 40 days. We identified 5226 DEGs, which were then classified into GO terms and KEGG pathways, showing significant enrichment in hormone signaling processes. Using WGCNA, we identified eight co-expression modules, two of which were significantly correlated with the IBA treatment. Additionally, 18 transcription factors that potentially facilitate ARs formation in mulberry were identified, and an exploratory analysis on the cis-regulatory elements associated with these transcription factors was conducted. The findings of this study provide a comprehensive understanding of the mechanisms of ARs in mulberry and offer theoretical support for the discovery and utilization of exceptional genetic resources within the species.


Asunto(s)
Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Morus , Raíces de Plantas , Factores de Transcripción , Morus/genética , Morus/metabolismo , Morus/crecimiento & desarrollo , Raíces de Plantas/genética , Raíces de Plantas/metabolismo , Raíces de Plantas/crecimiento & desarrollo , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Transcriptoma
5.
Environ Sci Technol ; 58(1): 960-969, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38150269

RESUMEN

SO2 reduction with CH4 to produce elemental sulfur (S8) or other sulfides is typically challenging due to high energy barriers and catalyst poisoning by SO2. Herein, we report that a comproportionation reaction (CR) induced by H2S recirculating significantly accelerates the reactions, altering reaction pathways and enabling flexible adjustment of the products from S8 to sulfides. Results show that SO2 can be fully reduced to H2S at a lower temperature of 650 °C, compared to the 800 °C required for the direct reduction (DR), effectively eliminating catalyst poisoning. The kinetic rate constant is significantly improved, with CR at 650 °C exhibiting about 3-fold higher value than DR at 750 °C. Additionally, the apparent activation energy decreases from 128 to 37 kJ/mol with H2S, altering the reaction route. This CR resolves the challenges related to robust sulfur-oxygen bond activation and enhances CH4 dissociation. During the process, the well-dispersed lamellar MoS2 crystallites with Co promoters (CoMoS) act as active species. H2S facilitates the comproportionation reaction, reducing SO2 to a nascent sulfur (Sx*). Subsequently, CH4 efficiently activates CoMoS in the absence of SO2, forming H2S. This shifts the mechanism from Mars-van Krevelen (MvK) in DR to sequential Langmuir-Hinshelwood (L-H) and MvK in CR. Additionally, it mitigates sulfation poisoning through this rapid activation reaction pathway. This unique comproportionation reaction provides a novel strategy for efficient sulfur resource utilization.


Asunto(s)
Metano , Dióxido de Azufre , Metano/química , Sulfuros/química , Temperatura , Azufre/química , Oxidación-Reducción
6.
Biochem Genet ; 62(2): 1087-1102, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37532836

RESUMEN

Actinomycetes are remarkable natural sources of active natural molecules and enzymes of considerable industrial value. Streptomyces mobaraensis is the first microorganism found to produce transglutaminase with broad industrial applications. Although transglutaminase in S. mobaraensis has been well studied over the past three decades, the genome of S. mobaraensis and its secondary metabolic potential were poorly reported. Here, we presented the complete genome of S. mobaraensis DSM40587 obtained from the German Collection of Microorganisms and Cell Cultures GmbH. It contains a linear chromosome of 7,633,041 bp and a circular plasmid of 23,857 bp. The chromosome with an average GC content of 73.49% was predicted to harbour 6683 protein-coding genes, seven rRNA and 69 tRNA genes. Comparative genomic analysis reveals its meaningful genomic characterisation. A comprehensive bioinformatics investigation identifies 35 putative BGCs (biosynthesis gene clusters) involved in synthesising various secondary metabolites. Of these, 13 clusters showed high similarity (> 55%) to known BGCs coding for polyketides, nonribosomal peptides, hopene, RiPP (Ribosomally synthesized and post-translationally modified peptides), and others. Furthermore, these BGCs with over 65% similarity to the known BGCs were analysed in detail. The complete genome of S. mobaraensis DSM40587 reveals its capacity to yield diverse bioactive natural products and provides additional insights into discovering novel secondary metabolites.

7.
Int J Mol Sci ; 25(5)2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38474082

RESUMEN

The removal of Cr(VI), a highly-toxic heavy metal, from industrial wastewater is a critical issue in water treatment research. Photocatalysis, a promising technology to solve the Cr(VI) pollution problem, requires urgent and continuous improvement to enhance its performance. To address this need, an electric field-assisted photocatalytic system (PCS) was proposed to meet the growing demand for industrial wastewater treatment. Firstly, we selected PAF-54, a nitrogen-rich porous organic polymer, as the PCS's catalytic material. PAF-54 exhibits a large adsorption capacity (189 mg/g) for Cr(VI) oxyanions through hydrogen bonding and electrostatic interaction. It was then coated on carbon paper (CP) and used as the photocatalytic electrode. The synergy between capacitive deionization (CDI) and photocatalysis significantly promotes the photoreduction of Cr(VI). The photocatalytic performance was enhanced due to the electric field's influence on the mass transfer process, which could strengthen the enrichment of Cr(VI) oxyanions and the repulsion of Cr(III) cations on the surface of PAF-54/CP electrode. In addition, the PCS system demonstrates excellent recyclability and stability, making it a promising candidate for chromium wastewater treatment.


Asunto(s)
Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/análisis , Aguas Residuales , Cromo/análisis , Adsorción , Cinética , Concentración de Iones de Hidrógeno
8.
Neuroimage ; 269: 119934, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36754123

RESUMEN

Human brain experiences vibration of certain magnitude and frequency during various physical activities such as vehicle transportation and machine operation, which may cause traumatic brain injury or other brain diseases. However, the mechanisms of brain pathogenesis due to vibration are not fully elucidated due to the lack of techniques to study brain functions while applying vibration to the brain at a specific magnitude and frequency. Here, this study reported a custom-built head-worn electromagnetic actuator that applied vibration to the brain in vivo at an accurate frequency inside a magnetic resonance imaging scanner while cerebral blood flow (CBF) was acquired. Using this technique, CBF values from 45 healthy volunteers were quantitatively measured immediately following vibration at 20, 30, 40 Hz, respectively. Results showed increasingly reduced CBF with increasing frequency at multiple regions of the brain, while the size of the regions expanded. Importantly, the vibration-induced CBF reduction regions largely fell inside the brain's default mode network (DMN), with about 58 or 46% overlap at 30 or 40 Hz, respectively. These findings demonstrate that vibration as a mechanical stimulus can change strain conditions, which may induce CBF reduction in the brain with regional differences in a frequency-dependent manner. Furthermore, the overlap between vibration-induced CBF reduction regions and DMN suggested a potential relationship between external mechanical stimuli and cognitive functions.


Asunto(s)
Encéfalo , Vibración , Humanos , Imagen por Resonancia Magnética , Cognición , Circulación Cerebrovascular/fisiología
9.
Environ Microbiol ; 25(2): 575-587, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36495168

RESUMEN

Glycerol dibiphytanyl glycerol tetraethers (GDGTs) are unique archaeal membrane-spanning lipids with 0-8 cyclopentane rings on the biphytanyl chains. The cyclization pattern of GDGTs is affected by many environmental factors, such as temperature and pH, but the underlying molecular mechanism remains elusive. Here, we find that the expression regulation of GDGT ring synthase genes grsA and grsB in thermophilic archaeon Sulfolobus acidocaldarius is temperature- and pH-dependent. Moreover, the presence of functional GrsA protein, or more likely its products cyclic GDGTs rather than the accumulation of GrsA protein itself, is required to induce grsB expression, resulting in temporal regulation of grsA and grsB expression. Our findings establish a molecular model of GDGT cyclization regulated by environment factors in a thermophilic ecosystem, which could be also relevant to that in mesophilic marine archaea. Our study will help better understand the biological basis for GDGT-based paleoclimate proxies. Archaea inhabit a wide range of terrestrial and marine environments. In response to environment fluctuations, archaea modulate their unique membrane GDGTs lipid composition with different strategies, in particular GDGTs cyclization significantly alters membrane permeability. However, the regulation details of archaeal GDGTs cyclization in response to different environmental factor changes remain unknown. We demonstrated, for the first time, thermophilic archaea orchestrate the temporal expression of GDGT ring synthases, leading to delicate control of GDGTs cyclization to respond environmental temperature and acidity stress. Our study provides insight into the regulation of archaea membrane plasticity, and the survival strategy of archaea in fluctuating environments.


Asunto(s)
Archaea , Ecosistema , Archaea/metabolismo , Temperatura , Glicerol/metabolismo , Lípidos de la Membrana/metabolismo
10.
Development ; 147(24)2020 12 23.
Artículo en Inglés | MEDLINE | ID: mdl-33361090

RESUMEN

Ventral bending of the embryonic tail within the chorion is an evolutionarily conserved morphogenetic event in both invertebrates and vertebrates. However, the complexity of the anatomical structure of vertebrate embryos makes it difficult to experimentally identify the mechanisms underlying embryonic folding. This study investigated the mechanisms underlying embryonic tail bending in chordates. To further understand the mechanical role of each tissue, we also developed a physical model with experimentally measured parameters to simulate embryonic tail bending. Actomyosin asymmetrically accumulated at the ventral side of the notochord, and cell proliferation of the dorsal tail epidermis was faster than that in the ventral counterpart during embryonic tail bending. Genetic disruption of actomyosin activity and inhibition of cell proliferation dorsally caused abnormal tail bending, indicating that both asymmetrical actomyosin contractility in the notochord and the discrepancy of epidermis cell proliferation are required for tail bending. In addition, asymmetrical notochord contractility was sufficient to drive embryonic tail bending, whereas differential epidermis proliferation was a passive response to mechanical forces. These findings showed that asymmetrical notochord contractility coordinates with differential epidermis proliferation mechanisms to drive embryonic tail bending.This article has an associated 'The people behind the papers' interview.


Asunto(s)
Actomiosina/genética , Morfogénesis/genética , Cola (estructura animal)/crecimiento & desarrollo , Actomiosina/metabolismo , Animales , Proliferación Celular/genética , Ciona/embriología , Ciona/genética , Ciona/crecimiento & desarrollo , Células Epiteliales/metabolismo , Contracción Muscular/fisiología , Notocorda/embriología , Notocorda/crecimiento & desarrollo , Cola (estructura animal)/embriología
11.
Nat Mater ; 21(6): 621-626, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35449221

RESUMEN

Atomic reconstruction has been widely observed in two-dimensional van der Waals structures with small twist angles1-7. This unusual behaviour leads to many novel phenomena, including strong electronic correlation, spontaneous ferromagnetism and topologically protected states1,5,8-14. Nevertheless, atomic reconstruction typically occurs spontaneously, exhibiting only one single stable state. Using conductive atomic force microscopy, here we show that, for small-angle twisted monolayer-multilayer graphene, there exist two metastable reconstruction states with distinct stacking orders and strain soliton structures. More importantly, we demonstrate that these two reconstruction states can be reversibly switched, and the switching can propagate spontaneously in an unusual domino-like fashion. Assisted by lattice-resolved conductive atomic force microscopy imaging and atomistic simulations, the detailed structure of the strain soliton networks has been identified and the associated propagation mechanism is attributed to the strong mechanical coupling among solitons. The fine structure of the bistable states is critical for understanding the unique properties of van der Waals structures with tiny twists, and the switching mechanism offers a viable means for manipulating their stacking states.


Asunto(s)
Grafito , Electrónica , Grafito/química
12.
Soft Matter ; 19(4): 708-722, 2023 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-36602136

RESUMEN

The growth of biological tissues, which is regulated by a variety of factors, can induce stresses that may, in turn, destabilize the tissues into diverse patterns. In most previous studies, however, tissue growth was usually assumed as a prescribed parameter independent of stresses, limiting our understanding of the mechanobiological morphogenesis of real tissues. In this paper, we propose a theoretical model to investigate the mechanobiological response of soft tissues undergoing stress-modulated growth. Linear stability analysis is first performed to elucidate the surface instability mechanism induced by stress-modulated volumetric growth. We further conduct finite element simulations to validate the theoretical prediction and, particularly, to capture the post-buckling pattern evolution. Our results show that the non-uniform stresses, which evolve with the tissue growth and morphogenesis, exert mechanical feedback on the growth itself, producing up-down asymmetric surface morphologies as observed in, for example, the gyrification of human brains and brain organoids. It is also revealed that large residual stresses are unnecessary to cause mechanobiological instability and subsequent asymmetric patterning, which has long been believed to be driven by sufficiently high stresses. The present work could help us to understand the morphological changes of biological tissues under physiological and pathological conditions.


Asunto(s)
Modelos Biológicos , Modelos Teóricos , Humanos , Morfogénesis , Estrés Mecánico , Análisis de Elementos Finitos
13.
World J Surg ; 47(9): 2221-2229, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37266695

RESUMEN

BACKGROUND: To secure surgical margin for hepatic lesion with involvement of the inferior vena cava (IVC), combined radical liver resection and IVC replacement are required. A novel method of replacing IVC by newly customized autologous great saphenous vein (GSV) grafts was introduced by this study. This study aimed at reporting the feasibility and outcome of this novel technique. METHODS: From January 2014 to January 2021, all consecutive patients who underwent concomitant hepatectomy and IVC replacement by autogenous GSV graft were enrolled in this study. Technical insights, intraoperative details, demographic data, postoperative complication, graft patency and survival data were collected and analyzed. RESULTS: Concomitant hepatectomy/autotransplantation (ERAT) with IVC replacement by autogenous GSV graft was successful in 47 patients and there was no 30-day mortality. There were 8 out of the 47 patients whose retrohepatic venae cavae were completely invaded by the lesion and their reconstructed IVCs were totally made from GSV grafts. The other 39 patients whose IVCs were partially invaded had their IVCs reconstructed by both the unaffected part of the IVC wall and newly customized GSV graft. Postoperative complications classified as Clavien-Dindo grade II, III A and III B were observed in 10, 7 and 3 patients, respectively. The median follow-up months were 35 months (29-80 months). No patient developed thrombosis of the graft and 100% patency of the IVC was observed throughout the study. CONCLUSION: In selected patients, hepatectomy/ERAT with IVC replacement by autogenous GSV graft is safe and feasible. The newly customized autologous GVS graft was ideal for reconstruction of the IVC in liver surgery.


Asunto(s)
Neoplasias Hepáticas , Vena Cava Inferior , Humanos , Vena Cava Inferior/cirugía , Vena Cava Inferior/patología , Neoplasias Hepáticas/cirugía , Vena Safena/patología , Hepatectomía/métodos , Complicaciones Posoperatorias/cirugía
14.
Nano Lett ; 22(10): 3889-3896, 2022 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-35507005

RESUMEN

Nanoindentation based on atomic force microscopy (AFM) can measure the elasticity of biomaterials and cells with high spatial resolution and sensitivity, but relating the data to quantitative mechanical properties depends on information on the local contact, which is unclear in most cases. Here, we demonstrate nonlocal deformation sensing on biorelevant soft matters upon AFM indentation by using nitrogen-vacancy centers in nanodiamonds, providing data for studying both the elasticity and capillarity without requiring detailed knowledge about the local contact. Using fixed HeLa cells for demonstration, we show that the apparent elastic moduli of the cells would have been overestimated if the capillarity was not considered. In addition, we observe that both the elastic moduli and the surface tensions are reduced after depolymerization of the actin cytoskeleton in cells. This work demonstrates that the nanodiamond sensing of nonlocal deformation with nanometer precision is particularly suitable for studying mechanics of soft biorelevant materials.


Asunto(s)
Nanodiamantes , Acción Capilar , Elasticidad , Células HeLa , Humanos , Microscopía de Fuerza Atómica
15.
Int J Mol Sci ; 24(16)2023 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-37628782

RESUMEN

The family Nidulariaceae, consisting of five genera including Cyathus, is a unique group of mushrooms commonly referred to as bird's nest fungi due to their striking resemblance to bird's nests. These mushrooms are considered medicinal mushrooms in Chinese medicine and have received attention in recent years for their anti-neurodegenerative properties. However, despite the interest in these mushrooms, very little is known about their mitochondrial genomes (mitogenomes). This study is the first comprehensive investigation of the mitogenomes of five Nidulariaceae species with circular genome structures ranging in size from 114,236 bp to 129,263 bp. Comparative analyses based on gene content, gene length, tRNA, and codon usage indicate convergence within the family Nidulariaceae and heterogeneity within the order Agaricales. Phylogenetic analysis based on a combined mitochondrial conserved protein dataset provides a well-supported phylogenetic tree for the Basidiomycetes, which clearly demonstrates the evolutionary relationships between Nidulariaceae and other members of Agaricales. Furthermore, phylogenetic inferences based on four different gene sets reveal the stability and proximity of evolutionary relationships within Agaricales. These results reveal the uniqueness of the family Nidulariaceae and its similarity to other members of Agaricales; provide valuable insights into the origin, evolution, and genetics of Nidulariaceae species; and enrich the fungal mitogenome resource. This study will help to expand the knowledge and understanding of the mitogenomes in mushrooms.


Asunto(s)
Agaricales , Genoma Mitocondrial , Agaricales/genética , Filogenia , Genoma Mitocondrial/genética , Intrones/genética , Reordenamiento Génico , Proteínas Mitocondriales
16.
Molecules ; 28(17)2023 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-37687209

RESUMEN

The culinary medicinal mushroom Hericium erinaceus holds significant global esteem and has garnered heightened interest within increasingly ageing societies due to its pronounced neuroprotective and anti-neuroinflammatory properties. Within this study, two novel diterpenes, 16-carboxy-13-epi-neoverrucosane (1) and Erinacine L (2); three known xylosyl cyathane diterpenoids, Erinacine A (3), Erinacine C (4), and Erinacine F (5); and four lanostane-type triterpenoids, and three cyclic dipeptides (10-12), in addition to orcinol (13), were isolated from the rice-based cultivation medium of H. erinaceus. Their structures were determined by NMR, HR-ESI-MS, ECD, and calculated NMR. Compound 1 marks a pioneering discovery as the first verrucosane diterpene originating from basidiomycetes, amplifying the scope of fungal natural product chemistry, and the intricate stereochemistry of Compound 5 has been comprehensively assessed for the first time. Compounds 2-5 not only showed encouraging neurotrophic activity in rat adrenal pheochromocytoma PC-12 cells, but also significantly inhibited lipopolysaccharide (LPS)-induced nitric oxide (NO) production in BV2 microglia cell cultures with IC50 values as low as 5.82 ± 0.18 µM. To elucidate the mechanistic underpinnings of these bioactivities, molecular docking simulation was used to analyze and support the interaction of 1 and 2 with inducible NO synthase (iNOS), respectively. In particular, compound 2, a cyathane-xyloside containing an unconventional hemiacetal moiety, is a compelling candidate for the prevention of neurodegenerative diseases. In summation, this investigation contributes substantively to the panorama of fungal diterpene structural diversity, concurrently furnishing additional empirical substantiation for the role of cyathane diterpenes in the amelioration of neurodegenerative afflictions.


Asunto(s)
Agaricales , Diterpenos , Animales , Ratas , Simulación del Acoplamiento Molecular , Diterpenos/farmacología
17.
Angew Chem Int Ed Engl ; 62(41): e202310435, 2023 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-37620985

RESUMEN

The prosperity of the lithium-ion battery market is dialectically accompanied by the depletion of corresponding resources and the accumulation of spent batteries. It is an urgent priority to develop green and efficient battery recycling strategies for helping ease resources and environmental pressures at the current stage. Here, we propose a mild and efficient lithium extracting strategy based on potential controllable redox couples. Active lithium in the spent battery without discharging is extracted using a series of tailored aprotic solutions comprised of polycyclic aromatic hydrocarbons and ethers. This ensures a safe yet efficient recycling process with nearly ≈100 % lithium recovery. We further investigate the Li+ -electron concerted redox reactions and the effect of solvation structure on kinetics during the extraction, and broaden the applicability of the Li-PAHs solution. This work can stimulate new inspiration for designing novel solutions to meet efficient and sustainable demands in recycling batteries.

18.
Biophys J ; 121(18): 3474-3485, 2022 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-35978549

RESUMEN

Rigidity of the extracellular matrix markedly regulates many cellular processes. However, how cells detect and respond to matrix rigidity remains incompletely understood. Here, we propose a unified two-dimensional multiscale framework accounting for the chemomechanical feedback to explore the interrelated cellular mechanosensing, polarization, and migration, which constitute the dynamic cascade in cellular response to matrix stiffness but are often modeled separately in previous theories. By combining integrin dynamics and intracellular force transduction, we show that substrate stiffness can act as a switch to activate or deactivate cell polarization. Our theory quantitatively reproduces rich stiffness-dependent cellular dynamics, including spreading, polarity selection, migration pattern, durotaxis, and even negative durotaxis, reported in a wide spectrum of cell types, and reconciles some inconsistent experimental observations. We find that a specific bipolarized mode can determine the optimal substrate stiffness, which enables the fastest cell migration rather than the largest traction forces that cells apply on the substrate. We identify that such a mechanical adaptation stems from the force balance across the whole cell. These findings could yield universal insights into various stiffness-mediated cellular processes within the context of tissue morphogenesis, wound healing, and cancer invasion.


Asunto(s)
Matriz Extracelular , Adhesiones Focales , Movimiento Celular , Matriz Extracelular/metabolismo , Adhesiones Focales/metabolismo , Integrinas/metabolismo , Fenómenos Mecánicos , Mecanotransducción Celular
19.
J Am Chem Soc ; 144(40): 18240-18245, 2022 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-36169321

RESUMEN

In Li-ion batteries, functional cosolvents could significantly improve the specific performance of the electrolyte, for example, the flame retardancy. In case the cosolvent shows strong Li+-coordinating ability, it could adversely influence the electrochemical Li+-intercalation reaction of the electrode. In this work, a noncoordinating functional cosolvent was proposed to enrich the functionality of the electrolyte while avoiding interference with the Li storage process. Hexafluorocyclotriphosphazene, an efficient flame-retardant agent with proper physicochemical properties, was chosen as a cosolvent for preparing functional electrolytes. The nonpolar phosphazene molecules with low electron-donating ability do not coordinate with Li+ and thus are excluded from the primary solvation sheath. In graphite-anode-based Li-ion batteries, the phosphazene molecules do not cointercalate with Li+ into the graphite lattice during the charging process, which helps to maintain integral anode structure and interface and contributes to stable cycling. The noncoordinating cosolvent was also applied to other types of electrode materials and batteries, paving a new way for high-performance electrochemical energy storage systems with customizable functions.

20.
Phys Rev Lett ; 129(12): 128101, 2022 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-36179209

RESUMEN

Growing axons are one-dimensional active structures that are important for wiring the brain and repairing nerves. However, the biophysical mechanisms underlying the complex kinetics of growing axons remain elusive. Here, we develop a theoretical framework to recapitulate force-regulated states and their transitions in growing axons. We demonstrate a unique negative feedback mechanism that defines four distinct kinetic states in a growing axon, whose transitional boundaries depend on the interplay between cytoskeletal dynamics and axon-substrate adhesion. A phase diagram for axonal growth is formulated based on two dimensionless numbers.


Asunto(s)
Axones , Encéfalo , Axones/fisiología
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