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1.
Ecol Evol ; 14(5): e11425, 2024 May.
Article in English | MEDLINE | ID: mdl-38746546

ABSTRACT

Understanding the relationship between plant diversity and invasibility is essential in invasion ecology. Species-rich communities are hypothesized to be more resistant to invasions than species-poor communities. However, while soil microorganisms play a crucial role in regulating this diversity-invasibility relationship, the effects of plant competition mode and soil nutrient status on their role remain unclear. To address this, we conducted a two-stage greenhouse experiment. Soils were first conditioned by growing nine native species separately in them for 1 year, then mixed in various configurations with soils conditioned using one, three, or six species, respectively. Next, we inoculated the mixed soil into sterilized substrate soil and planted the alien species Rhus typhina and native species Ailanthus altissima as test plants. We set up two competition modes (intraspecific and interspecific) and two nutrient levels (fertilization using slow-release fertilizer and nonfertilization). Under intraspecific competition, regardless of fertilization, the biomass of the alien species was higher in soil conditioned by six native species. By contrast, under interspecific competition, the biomass increased without fertilization but remained stable with fertilization in soil conditioned by six native species. Analysis of soil microbes suggests that pathogens and symbiotic fungi in diverse plant communities influenced R. typhina growth, which varied with competition mode and nutrient status. Our findings suggest that the soil microbiome is pivotal in mediating the diversity-invasibility relationship, and this influence varies according to competition mode and nutrient status.

2.
Ageing Res Rev ; 98: 102324, 2024 May 16.
Article in English | MEDLINE | ID: mdl-38762100

ABSTRACT

Progressive neuronal dysfunction and death are key features of neurodegenerative diseases; therefore, promoting neurogenesis in neurodegenerative diseases is crucial. With advancements in proteomics and high-throughput sequencing technology, it has been demonstrated that histone post-transcriptional modifications (PTMs) are often altered during neurogenesis when the brain is affected by disease or external stimuli and that the degree of histone modification is closely associated with the development of neurodegenerative diseases. This review aimed to show the regulatory role of histone modifications in neurogenesis and neurodegenerative diseases by discussing the changing patterns and functional significance of histone modifications, including histone methylation, acetylation, ubiquitination, phosphorylation, and lactylation. Finally, we explored the control of neurogenesis and the development of neurodegenerative diseases by artificially modulating histone modifications.

3.
Biomed Pharmacother ; 176: 116806, 2024 May 25.
Article in English | MEDLINE | ID: mdl-38796971

ABSTRACT

Central nervous system (CNS) damage is usually irreversible owing to the limited regenerative capability of neurons. Following CNS injury, astrocytes are reactively activated and are the key cells involved in post-injury repair mechanisms. Consequently, research on the reprogramming of reactive astrocytes into neurons could provide new directions for the restoration of neural function after CNS injury and in the promotion of recovery in various neurodegenerative diseases. This review aims to provide an overview of the means through which reactive astrocytes around lesions can be reprogrammed into neurons, to elucidate the intrinsic connection between the two cell types from a neurogenesis perspective, and to summarize what is known about the neurotranscription factors, small-molecule compounds and MicroRNA that play major roles in astrocyte reprogramming. As the malignant proliferation of astrocytes promotes the development of glioblastoma multiforme (GBM), this review also examines the research advances on and the theoretical basis for the reprogramming of GBM cells into neurons and discusses the advantages of such approaches over traditional treatment modalities. This comprehensive review provides new insights into the field of GBM therapy and theoretical insights into the mechanisms of neurological recovery following neurological injury and in GBM treatment.

4.
Nat Commun ; 15(1): 2590, 2024 Mar 22.
Article in English | MEDLINE | ID: mdl-38519505

ABSTRACT

Group 1 elements exhibit the lowest electronegativity values in the Periodic Table. The chemical reduction of Group 1 metal cations M+ to M(0) is extremely challenging. Common tetraaryl borates demonstrate limited redox properties and are prone to decomposition upon oxidation. In this study, by employing simple yet versatile bipyridines as ligands, we synthesized a series of redox-active borate anions characterized by NMR and X-ray single-crystal diffraction. Notably, the borate anion can realize the reduction of Li+, generating elemental lithium metal and boron radical, thereby demonstrating its potent reducing ability. Furthermore, it can serve as a powerful two-electron-reducing reagent and be readily applied in various reductive homo-coupling reactions and Birch reduction of acridine. Additionally, this borate anion demonstrates its catalytic ability in the selective two-electron reduction of CO2 into CO.

5.
Chem Rec ; 23(12): e202300238, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37698286

ABSTRACT

Electron-precise B-B bonded compounds are valuable reagents in organic syntheses, which can be used as key starting material for the synthesis of functionalized organoboranes. Bis(pinacolato)diborane(4) B2 pin2 and its derivatives are among the most studied diboron species. However, their B-B bonds usually need to be activated by transition metal catalysts or bases for further transformations. Recently, many well-designed/reactive electron-precise B-B bonded compounds have been developed, which could facilitate direct reactions with small molecules, unsaturated substrates, and electrophiles. This review highlights the synthesis, structure, and reactivity of neutral and anionic B-B bonded compounds.

6.
Nat Commun ; 14(1): 4363, 2023 Jul 20.
Article in English | MEDLINE | ID: mdl-37474521

ABSTRACT

Four-dimensional scanning transmission electron microscopy (4D-STEM) has recently gained widespread attention for its ability to image atomic electric fields with sub-Ångstrom spatial resolution. These electric field maps represent the integrated effect of the nucleus, core electrons and valence electrons, and separating their contributions is non-trivial. In this paper, we utilized simultaneously acquired 4D-STEM center of mass (CoM) images and annular dark field (ADF) images to determine the projected electron charge density in monolayer MoS2. We evaluate the contributions of both the core electrons and the valence electrons to the derived electron charge density; however, due to blurring by the probe shape, the valence electron contribution forms a nearly featureless background while most of the spatial modulation comes from the core electrons. Our findings highlight the importance of probe shape in interpreting charge densities derived from 4D-STEM and the need for smaller electron probes.

7.
Chem Rev ; 123(6): 2737-2831, 2023 Mar 22.
Article in English | MEDLINE | ID: mdl-36898130

ABSTRACT

Confined fluids and electrolyte solutions in nanopores exhibit rich and surprising physics and chemistry that impact the mass transport and energy efficiency in many important natural systems and industrial applications. Existing theories often fail to predict the exotic effects observed in the narrowest of such pores, called single-digit nanopores (SDNs), which have diameters or conduit widths of less than 10 nm, and have only recently become accessible for experimental measurements. What SDNs reveal has been surprising, including a rapidly increasing number of examples such as extraordinarily fast water transport, distorted fluid-phase boundaries, strong ion-correlation and quantum effects, and dielectric anomalies that are not observed in larger pores. Exploiting these effects presents myriad opportunities in both basic and applied research that stand to impact a host of new technologies at the water-energy nexus, from new membranes for precise separations and water purification to new gas permeable materials for water electrolyzers and energy-storage devices. SDNs also present unique opportunities to achieve ultrasensitive and selective chemical sensing at the single-ion and single-molecule limit. In this review article, we summarize the progress on nanofluidics of SDNs, with a focus on the confinement effects that arise in these extremely narrow nanopores. The recent development of precision model systems, transformative experimental tools, and multiscale theories that have played enabling roles in advancing this frontier are reviewed. We also identify new knowledge gaps in our understanding of nanofluidic transport and provide an outlook for the future challenges and opportunities at this rapidly advancing frontier.

8.
Opt Express ; 31(4): 6974-6981, 2023 Feb 13.
Article in English | MEDLINE | ID: mdl-36823943

ABSTRACT

A sulfur dioxide (SO2) gas sensor based on the photoacoustic spectroscopy technology in a sulfur hexafluoride (SF6) gas matrix was demonstrated for SF6 decomposition components monitoring in the power system. A passive Q-switching laser diode (LD) pumped all-solid-state 266 nm deep-ultraviolet laser was exploited as the laser excitation source. The photoacoustic signal amplitude is linear related to the incident optical power, whereas, a random laser power jitter is inevitable since the immature laser manufacturing technology in UV spectral region. A compact laser power stabilization system was developed for better sensor performance by adopting a photodetector, a custom-made internal closed-loop feedback controller and a Bragg acousto-optic modulator (AOM). The out-power stability of 0.04% was achieved even though the original power stability was 0.41% for ∼ 2 hours. A differential two-resonator photoacoustic cell (PAC) was designed for weak photoacoustic signal detection. The special physical constants of SF6 buffer gas induced a high-Q factor of 85. A detection limit of 140 ppbv was obtained after the optimization, which corresponds to a normalized noise equivalent absorption coefficient of 3.2 × 10-9 cm-1WHz-1/2.

9.
Biochem Pharmacol ; 204: 115197, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35926651

ABSTRACT

Memory CD8+T cells participate in the fight against infection and tumorigenesis as well as in autoimmune disease progression because of their efficient and rapid immune response, long-term survival, and continuous differentiation. At each stage of their formation, maintenance, and function, the cell metabolism must be adjusted to match the functional requirements of the specific stage. Notably, enhanced glycolytic metabolism can generate sufficient levels of adenosine triphosphate (ATP) to form memory CD8+T cells, countering the view that glycolysis prevents the formation of memory CD8+T cells. This review focuses on how glycometabolism regulates memory CD8+T cells and highlights the key mechanisms through which the mammalian target of rapamycin (mTOR) signaling pathway affects memory CD8+T cell formation, maintenance, and function by regulating glycometabolism. In addition, different subpopulations of memory CD8+T cells exhibit different metabolic flexibility during their formation, survival, and functional stages, during which the energy metabolism may be critical. These findings which may explain why enhanced glycolytic metabolism can give rise to memory CD8+T cells. Modulating the metabolism of memory CD8+T cells to influence specific cell fates may be useful for disease treatment.


Subject(s)
Immunologic Memory , TOR Serine-Threonine Kinases , Adenosine Triphosphate/metabolism , Animals , CD8-Positive T-Lymphocytes , Cell Differentiation , Glycolysis , Mice , Mice, Inbred C57BL , TOR Serine-Threonine Kinases/metabolism
10.
Insects ; 13(8)2022 Aug 09.
Article in English | MEDLINE | ID: mdl-36005341

ABSTRACT

Hierodulinae is a species-rich mantid subfamily, with some species bearing a notable leaf-like pronotum. However, the evolutionary pattern and taxonomic significance of the leaf-like pronotum are largely unknown. Here, we present a phylogenomic analysis of the Hierodulinae genera Rhombodera Burmeister, 1838, and Hierodula Burmeister, 1838 based on mitochondrial genomes. We also describe a new species, namely Rhombodera hyalina sp. nov. from Guangxi, China. Our phylogenetic result, together with the evidence from male genitalia, suggests the division of the Oriental Hierodula and Rhombodera complex into three clades. We find a complex pattern on the evolution of the leaf-like pronotum, which is present in at least five lineages, respectively, of the above three clades.

11.
Int J Biol Macromol ; 216: 487-497, 2022 Sep 01.
Article in English | MEDLINE | ID: mdl-35810850

ABSTRACT

Common vetch (CV), a leguminous crop cultivated for green manure and fodder rich in protein and starch, is widespread over much area of the northern hemisphere. Its seeds can be used as a protein source to human consumption. CV protein isolates (CVPI) and major protein fractions (CV albumin protein, CVAP; CV globulin protein, CVGP; CV glutelin protein, CVGTP) from 4 samples were investigated the properties to facilitate full use of protein resources. Protein comprises 27.70 %-32.14 % of the dry CV seed weight, which is mainly composed by CVAP (26.79 %-56.12 %) and CVGP (22.78 %-52.42 %). CVPI, CVAP and CVGP mainly presented 7S and 11S components. CVGTP mainly contained the 11S component. They showed difference in thermal properties and surface hydrophobicity. Circular dichroism data showed that α-helix was their major secondary structure. CVPI and major protein fractions exhibited a U-shape protein solubility. CVPI and CVAP had advantages in emulsifying and foaming properties. This study provided novel insights on unexploited sources of CV proteins with interesting characteristics in terms of potential uses as protein-based foods.


Subject(s)
Fabaceae , Globulins , Vicia sativa , Fabaceae/chemistry , Globulins/chemistry , Humans , Plant Proteins/chemistry , Seeds/chemistry , Vicia sativa/metabolism
12.
Dalton Trans ; 51(32): 12125-12136, 2022 Aug 16.
Article in English | MEDLINE | ID: mdl-35876119

ABSTRACT

Biomass-based porous carbon materials have attracted considerable attention because of their simple, low-cost, green, and pollution-free preparation process. Owing to their unique tubular structure and subsequent activation process, they often have a well-developed pore structure. Biomass-based carbon materials with three-dimensional hierarchical pores and polyatomic doping are regarded as promising electrode materials in the field of energy storage. In this study, cornstalk was used as the biomass and a pioneering approach was used to prepare porous carbon co-doped with N, B, and P. The B,N,P-codoped porous carbon has a three-dimensional honeycomb-like network structure with uniformly distributed and interwoven macro-, meso-, and micropores. Furthermore, it has an ultra-high specific surface area of 3123.5 m2 g-1, a high specific capacitance of 342.5 F g-1 at a current density of 0.5 A g-1, and an energy density of up to 26.18 W h kg-1. This study demonstrates a multi-element co-doping strategy that enhances the performance of cornstalk as a precursor of a supercapacitor electrode material and has important implications in the high-value-added utilisation of waste straw.


Subject(s)
Carbon , Biomass , Carbon/chemistry , Electric Capacitance , Electrodes , Porosity
13.
RSC Adv ; 12(15): 9299-9303, 2022 Mar 21.
Article in English | MEDLINE | ID: mdl-35424867

ABSTRACT

A new route to control the microstructure and properties of carbon aerogels via vacuum impregnation is presented. The results show that the enhanced carbon aerogels exhibit uniform pore size distribution (∼50 nm), a high compressive strength of 77.0 MPa and a low thermal conductivity of 0.15-1.62 W m-1 K-1 at 25 to 1600 °C.

14.
Appl Opt ; 60(24): 7346-7350, 2021 Aug 20.
Article in English | MEDLINE | ID: mdl-34613022

ABSTRACT

Five-hundred-watt cylindrical vector beams (CVBs) at 1030 nm with the 3 dB linewidth being less than 0.25 nm have been generated from a narrow linewidth all-fiber linearly polarized laser by metasurface extracavity conversion. At maximum output power, the transmission efficiency and polarization extinction ratio of radially polarized cylindrical vector beams (RP-CVBs) are beyond 98% and 95%, respectively. The average power is approximately an order higher than previously reported high-power narrow-linewidth CVBs generated from fiber lasers. The temperature rise of the metasurface is less than 10°C at 500 W output power, which means that the system can be further power-scaled in the near future. The high-power, high-purity, and high-efficiency RP-CVBs generated by the metasurface demonstrate potential application of a metasurface in high-power CVBs lasers.

15.
Front Immunol ; 12: 725330, 2021.
Article in English | MEDLINE | ID: mdl-34386017

ABSTRACT

Gynecologic malignancies, mainly including ovarian cancer, cervical cancer and endometrial cancer, are leading causes of death among women worldwide with high incidence and mortality rate. Recently, adoptive T cell therapy (ACT) using engineered T cells redirected by genes which encode for tumor-specific T cell receptors (TCRs) or chimeric antigen receptors (CARs) has demonstrated a delightful potency in B cell lymphoma treatment. Researches impelling ACT to be applied in treating solid tumors like gynecologic tumors are ongoing. This review summarizes the preclinical research and clinical application of engineered T cells therapy for gynecologic cancer in order to arouse new thoughts for remedies of this disease.


Subject(s)
Cell- and Tissue-Based Therapy/methods , Genital Neoplasms, Female/therapy , Immunotherapy, Adoptive/methods , Receptors, Chimeric Antigen/immunology , T-Lymphocytes/transplantation , Animals , Female , Genital Neoplasms, Female/immunology , Genital Neoplasms, Female/pathology , Humans , T-Lymphocytes/immunology
16.
Opt Express ; 29(6): 7986-7997, 2021 Mar 15.
Article in English | MEDLINE | ID: mdl-33820254

ABSTRACT

In this work, quasi-static mode degradation in high power fiber amplifiers has been investigated experimentally. An increase of M2 from 1.3 to 2.6 with distortion of the beam profile is observed, which results in the signal spectra and backward light characterization departing from the traditional phenomena. The amplifier has been operated at the same input pump power of 705 W for nearly 2.2 hours to investigate the relationship between quasi-static mode degradation and photodarkening. The evolution of M2 factor/beam profile, mode correlation coefficient and output laser power at different working times indicate that the quasi-static mode degradation in the high power fiber amplifiers is dependent on photodarkening and evolves on the scale of tens of minutes. A visible green light has been injected to photobleach the gain fiber for 19 hours, which reveals that the quasi-static mode degradation has been suppressed simultaneously. To the best of our knowledge, this is the first detail report of photodarkening-induced quasi-static degradation in high power fiber amplifiers.

17.
Microb Pathog ; 153: 104776, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33548482

ABSTRACT

Listeria monocytogenes is a foodborne pathogen that causes systemic infections by crossing the intestinal barrier. However, in vitro analysis of the interaction of L. monocytogenes and small intestinal epithelium has yet to be fully elucidated. To study host responses from intestinal epithelium during L. monocytogenes infection, we used the co-culture model of small intestinal organoids and L. monocytogenes. Results showed that L. monocytogenes mediated damage to intestinal epithelium, especially intestinal stem cells. L. monocytogenes was found to reduce budding rate and increase mortality of organoids. Moreover, it affected the proliferation of epithelial cells and numbers of secretory cells. In addition, it was demonstrated that L. monocytogenes stimulated a reduction in the number of Lgr5+ stem cells. Furthermore, L. monocytogenes affected the expression of Hes1, Math1 and Sox9 to interfere with the differentiation of intestinal stem cells. Collectively, our findings reveal the effects of L. monocytogenes infection on intestinal stem cells and demonstrate that small intestinal organoid is a suitable experimental model for studying intestinal epithelium-pathogen interactions.


Subject(s)
Listeria monocytogenes , Coculture Techniques , Intestinal Mucosa , Intestines , Organoids , Stem Cells
18.
Nano Lett ; 21(5): 1935-1942, 2021 03 10.
Article in English | MEDLINE | ID: mdl-33635654

ABSTRACT

Optical imaging with nanometer resolution offers fundamental insights into light-matter interactions. Traditional optical techniques are diffraction limited with a spatial resolution >100 nm. Optical super-resolution and cathodoluminescence techniques have higher spatial resolutions, but these approaches require the sample to fluoresce, which many materials lack. Here, we introduce photoabsorption microscopy using electron analysis, which involves spectrally specific photoabsorption that is locally probed using a scanning electron microscope, whereby a photoabsorption-induced surface photovoltage modulates the secondary electron emission. We demonstrate spectrally specific photoabsorption imaging with sub-20 nm spatial resolution using silicon, germanium, and gold nanoparticles. Theoretical analysis and Monte Carlo simulations are used to explain the basic trends of the photoabsorption-induced secondary electron signal. Based on our current experiments and this analysis, we expect that the spatial resolution can be further improved to a few nanometers, thereby offering a general approach for nanometer-scale optical spectroscopic imaging and material characterization.

19.
Nano Lett ; 20(11): 7927-7932, 2020 11 11.
Article in English | MEDLINE | ID: mdl-33079557

ABSTRACT

The individual and collective behavior of ions near electrically charged interfaces is foundational to a variety of electrochemical phenomena encountered in biology, energy, and the environment. While many theories have been developed to predict the interfacial arrangements of counterions, direct experimental observations and validations have remained elusive. Utilizing cryo-electron microscopy, here we directly visualize individual counterions and reveal their discrete interfacial layering. Comparison with simulations suggests the strong effects of finite ionic size and electrostatic interactions. We also uncover correlated ionic structures under extreme confinement, with the channel widths approaching the ionic diameter (∼1 nm). Our work reveals the roles of ionic size, valency, and confinement in determining the structures of liquid-solid interfaces and opens up new opportunities to study such systems at the single-ion level.

20.
Drug Deliv ; 27(1): 1034-1043, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32627602

ABSTRACT

Knee osteoarthritis (OA) is a common degenerative disease. Intra-articular administration of flurbiprofen is frequently employed in clinic to treat OA, while repeated injections are required because of the limited effective duration. To improve therapeutic outcome and prolong the treatment interval, a poly(ε-caprolactone-co-lactide)-b-poly(ethylene glycol)-b-poly(ε-caprolactone-co-lactide) (PCLA-PEG-PCLA) triblock copolymer based flurbiprofen thermosensitive gel for the sustained intra-articular drug delivery was designed in this study. The anti-OA effects of this flurbiprofen thermogel were investigated on collagenase II-induced rat knee OA model by multiple approaches and compared with that of conventional sodium hyaluronate and flurbiprofen injecta. In vitro drug release studies indicated that flurbiprofen was sustained released from the thermosensitive gel for more than three weeks. This sustained drug release system exerted comparable short-term analgesic effects and distinctly improved long-term analgesic efficacy in terms of the increased percentage of the total ipsilateral paw print intensity and the reduced Knee-Bend scores of OA rats. The inflammatory response was attenuated in the samples of flurbiprofen gel treated group by showing decreased IL-1, IL-6, and IL-11 levels in the joint fluid and down-regulated IL-1, IL-6, IL-11, COX-2, TNF-α, and NF-κB/p65 expression in the articular cartilages. The results suggest the suitability of thermosensitive copolymer PCLA-PEG-PCLA for sustained intra-articular effects of flurbiprofen and provide in vivo experimental evidence for potential clinical application of this flurbiprofen delivery system to better management of OA cases.


Subject(s)
Cartilage, Articular/drug effects , Cyclooxygenase Inhibitors/administration & dosage , Cyclooxygenase Inhibitors/pharmacology , Cytokines/drug effects , Flurbiprofen/administration & dosage , Flurbiprofen/pharmacology , Gels , Osteoarthritis, Knee/metabolism , Animals , Cartilage, Articular/metabolism , Cyclooxygenase 2/drug effects , Cyclooxygenase 2/metabolism , Cytokines/metabolism , Delayed-Action Preparations , Disease Models, Animal , Drug Carriers , Drug Delivery Systems , In Vitro Techniques , Injections, Intra-Articular , Interleukin-1/metabolism , Interleukin-11/metabolism , Interleukin-6/metabolism , Matrix Metalloproteinase 8/toxicity , Osteoarthritis, Knee/chemically induced , Pain Measurement , Polyesters , Polyethylene Glycols , Polymers , Rats , Stifle/drug effects , Stifle/metabolism , Synovial Fluid/drug effects , Synovial Fluid/metabolism , Time Factors , Transcription Factor RelA/drug effects , Transcription Factor RelA/metabolism , Tumor Necrosis Factor-alpha/drug effects , Tumor Necrosis Factor-alpha/metabolism
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