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1.
Nature ; 626(7998): 294-299, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38326595

ABSTRACT

An essential ingredient for the production of Majorana fermions for use in quantum computing is topological superconductivity1,2. As bulk topological superconductors remain elusive, the most promising approaches exploit proximity-induced superconductivity3, making systems fragile and difficult to realize4-7. Due to their intrinsic topology8, Weyl semimetals are also potential candidates1,2, but have always been connected with bulk superconductivity, leaving the possibility of intrinsic superconductivity of their topological surface states, the Fermi arcs, practically without attention, even from the theory side. Here, by means of angle-resolved photoemission spectroscopy and ab initio calculations, we identify topological Fermi arcs on two opposing surfaces of the non-centrosymmetric Weyl material trigonal PtBi2 (ref. 9). We show these states become superconducting at temperatures around 10 K. Remarkably, the corresponding coherence peaks appear as the strongest and sharpest excitations ever detected by photoemission from solids. Our findings indicate that superconductivity in PtBi2 can occur exclusively at the surface, rendering it a possible platform to host Majorana modes in intrinsically topological superconductor-normal metal-superconductor Josephson junctions.

2.
Nat Commun ; 15(1): 1467, 2024 Feb 17.
Article in English | MEDLINE | ID: mdl-38368411

ABSTRACT

The noncentrosymmetric ferromagnetic Weyl semimetal CeAlSi with simultaneous space-inversion and time-reversal symmetry breaking provides a unique platform for exploring novel topological states. Here, by employing multiple experimental techniques, we demonstrate that ferromagnetism and pressure can serve as efficient parameters to tune the positions of Weyl nodes in CeAlSi. At ambient pressure, a magnetism-facilitated anomalous Hall/Nernst effect (AHE/ANE) is uncovered. Angle-resolved photoemission spectroscopy (ARPES) measurements demonstrated that the Weyl nodes with opposite chirality are moving away from each other upon entering the ferromagnetic phase. Under pressure, by tracing the pressure evolution of AHE and band structure, we demonstrate that pressure could also serve as a pivotal knob to tune the positions of Weyl nodes. Moreover, multiple pressure-induced phase transitions are also revealed. These findings indicate that CeAlSi provides a unique and tunable platform for exploring exotic topological physics and electron correlations, as well as catering to potential applications, such as spintronics.

3.
Int J Biol Macromol ; 251: 126191, 2023 Aug 12.
Article in English | MEDLINE | ID: mdl-37573918

ABSTRACT

Sorption dehumidification, as an energy-saving and eco-friendly approach, has been emerging in application for air dehumidification. Here, a prospective method is proposed to prepare biomass-based hygroscopic aerogels that are easily applicable, sustainable, high-efficient, and recyclable. The chitosan-based aerogel with a porous and hydrophilic network acts as the carrier and water reservoir for the uniformly distributed lithium chloride hygroscopic salt, and provides the hygroscopic salt with more liberal water channels to facilitate moisture capture and transfer. As a consequence, the prepared chitosan/polyvinyl alcohol@lithium chloride (chitosan/PVA@LiCl) hygroscopic aerogel exhibits an excellent moisture absorption capacity of up to 2.77 g g-1 at a relative humidity of 90 %. Meanwhile, as the chitosan/PVA@LiCl aerogel is set in a closed space about 2200 times larger than its own volume, the relative humidity can be reduced from 90 % to 32 % within 2 h, and further lower to 25 % after 4 h. Furthermore, combined with multi-walled carbon nanotubes, the photothermal hygroscopic aerogel is obtained that can rapidly desorb water under sunlight, thus to realize energy-free cycle. Overall, the renewable biomass-based aerogel materials with the advantages of simple preparation and excellent hygroscopic performance provides a new path for the development of sorption dehumidification technology.

4.
Polymers (Basel) ; 15(8)2023 Apr 08.
Article in English | MEDLINE | ID: mdl-37111971

ABSTRACT

A cost-effective and sustainable method is successfully developed to produce lignin-based cryogels with a mechanically robust 3D interconnected structure. A choline chloride-lactic acid (ChCl-LA)-based deep eutectic solvent (DES) is used as a cosolvent to promote the synthesis of lignin-resorcinol-formaldehyde (LRF) gels that can self-assemble a robust string-bead-like framework. The molar ratio of LA to ChCl in DES has a significant influence on the gelation time and properties of the ensuing gels. Moreover, it is discovered that doping the metal-organic framework (MOF) during the sol-gel process can greatly accelerate the gelation of lignin. It takes a mere 4 h to complete the LRF gelation process at a DES ratio of 1:5 combined with 5% MOF. This study yields LRF carbon cryogels doped with copper that exhibit 3D interconnected bead-like carbon spheres with a prominent micropore of 1.2 nm. A specific capacitance as high as 185 F g-1 can be obtained for the LRF carbon electrode at a current density of 0.5 A g-1, and it has an excellent long-term cycling stability. This study provides a novel method of synthesizing high-lignin-content carbon cryogels with promising potential for application in the field of energy storage devices.

5.
Transpl Immunol ; 78: 101830, 2023 06.
Article in English | MEDLINE | ID: mdl-36972853

ABSTRACT

Cytokine storm development is a major cause of many transplant-related complications, especially during the conditioning regimen. This study aimed to characterize the cytokine profile and determine its prognostic impact during conditioning in patients undergoing subsequent haploidentical stem cell transplantation. A total of 43 patients were enrolled in this study. Sixteen cytokines associated with cytokine release syndrome (CRS) during anti-thymocyte globulin (ATG) treatment were quantified in patients undergoing haploidentical stem cell transplantation. Thirty-six (83.7%) patients developed CRS during ATG treatment; most of those cases (33/36; 91.7%) were classified as grade 1 CRS, whereas only three (7.0%) developed grade 2 CRS. CRS was observed more frequently on the first (15/43; 34.9%) and second day (30/43; 69.8%) of ATG infusion. No factors were identified that could predict the development of CRS on the first day of ATG treatment. Five of the 16 cytokines (interleukins 6, 8, and 10 (IL-6, IL-8, and IL-10), C-reactive protein (CRP), and procalcitonin (PCT)) were significantly elevated during ATG treatment, although only the level of IL-6, IL-10, and PCT were associated with the severity of CRS. However, neither CRS nor the cytokine levels significantly impacted the development of acute graft-versus-host disease (GVHD) or cytomegalovirus (CMV) infection or affected overall survival.


Subject(s)
Cytomegalovirus Infections , Graft vs Host Disease , Hematopoietic Stem Cell Transplantation , Humans , Interleukin-10 , Prognosis , Interleukin-6 , Antilymphocyte Serum/therapeutic use , Cytokines/metabolism , Transplantation Conditioning , Retrospective Studies
6.
Biomater Adv ; 137: 212848, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35929243

ABSTRACT

Hyperbranched polymers hold great promise in nanomedicine for their controlled chemical structures, sizes, multiple terminal groups and enhanced stability than linear amphiphilic polymer assemblies. However, the rational design of hyperbranched polymer-based nanomedicine with low toxic materials, selective cellular uptake, controlled drug release, as well as real-time drug release tracking remains challenging. In this work, a hyperbranched multifunctional prodrug HBPSi-SS-HCPT is constructed basing on the nonconventional aggregation-induced emission (AIE) featured hyperbranched polysiloxanes (HBPSi). The HBPSi is a biocompatible AIE macromolecule devoid of conjugates, showing a high quantum yield of 17.88% and low cytotoxicity. By covalently grafting the anticancer drug, 10-hydroxycamptothecin (HCPT), to the HBPSi through 3,3'-dithiodipropionic acid, HBPSi-SS-HCPT is obtained. The HBPSis demonstrate obvious AIE features and it turned to aggregation-caused quenching (ACQ) after grafting HCPT owing to the FRET behavior between HBPSi and HCPT in HBPSi-SS-HCPT. In addition to on-demand HCPT release in response to changes in environmental pH and glutathione, a series of in vitro and in vivo studies revealed that HBPSi-SS-HCPT exhibits enhanced accumulation in tumor tissues through the enhanced permeation and retention (EPR) effect and preferential cancer cell uptake by charge reversal, thus resulting in apoptotic cell death subsequently. This newly developed multifunctional HBPSi-SS-HCPT prodrug provides a biocompatible strategy for controlled drug delivery, preferential cancer cell uptake, on-demand drug release and enhanced antitumor efficacy.


Subject(s)
Prodrugs , Drug Delivery Systems , Drug Liberation , Polymers/chemistry , Prodrugs/pharmacology , Siloxanes
7.
Exp Hematol Oncol ; 11(1): 25, 2022 May 03.
Article in English | MEDLINE | ID: mdl-35505384

ABSTRACT

BACKGROUND: Acute graft-versus-host disease (aGVHD) remains the major cause of early mortality after haploidentical related donor (HID) hematopoietic stem cell transplantation (HSCT). We aimed to establish a comprehensive model which could predict severe aGVHD after HID HSCT. METHODS: Consecutive 470 acute leukemia patients receiving HID HSCT according to the protocol registered at https://clinicaltrials.gov (NCT03756675) were enrolled, 70% of them (n = 335) were randomly selected as training cohort and the remains 30% (n = 135) were used as validation cohort. RESULTS: The equation was as follows: Probability (grade III-IV aGVHD) = [Formula: see text], where Y = -0.0288 × (age) + 0.7965 × (gender) + 0.8371 × (CD3 + /CD14 + cells ratio in graft) + 0.5829 × (donor/recipient relation) - 0.0089 × (CD8 + cell counts in graft) - 2.9046. The threshold of probability was 0.057392 which helped separate patients into high- and low-risk groups. The 100-day cumulative incidence of grade III-IV aGVHD in the low- and high-risk groups was 4.1% (95% CI 1.9-6.3%) versus 12.8% (95% CI 7.4-18.2%) (P = 0.001), 3.2% (95% CI 1.2-5.1%) versus 10.6% (95% CI 4.7-16.5%) (P = 0.006), and 6.1% (95% CI 1.3-10.9%) versus 19.4% (95% CI 6.3-32.5%) (P = 0.017), respectively, in total, training, and validation cohort. The rates of grade III-IV skin and gut aGVHD in high-risk group were both significantly higher than those of low-risk group. This model could also predict grade II-IV and grade I-IV aGVHD. CONCLUSIONS: We established a model which could predict the development of severe aGVHD in HID HSCT recipients.

8.
J Mater Chem B ; 10(22): 4306-4320, 2022 06 08.
Article in English | MEDLINE | ID: mdl-35586908

ABSTRACT

The poor penetration into deep tumor tissues of nanomedicines could not inhibit the production of lactic acid by deep tumor glycolysis, which leads to the accumulation of lactic acid and promotes tumor metastasis. In order to increase tumor penetration, it remains challenging to avoid tumor metastasis by the direct degradation of the extracellular matrix (ECM). Herein, in order to increase tumor penetration, a nano-platform, which can reduce extracellular matrix (ECM) production, and inhibit the glycolysis of deep tumors by releasing ethylenediaminetetraacetic acid (EDTA) is reported. In this design, EDTA and indocyanine green (ICG) are encapsulated in the liposome by a thin-film hydration method, and folic acid (FA) and the polyethyleneimine polymer (FA-PEI) are applied to coat the surface of liposomes through electrostatic interactions, and the FA-EDTA/ICG-Lip nanoparticles are obtained. FA-EDTA/ICG-Lip NPs can release EDTA and ICG in lysosomes (pH 4.5) to reduce ECM production by down-regulating transforming growth factor ß (TGF-ß) and activating an immune response by inducing tumor cell immunogenic cell death (ICD), respectively. Simultaneously, EDTA inhibits glycolysis of deep tumors by chelating Mg2+. By avoiding tumor metastasis, the strategy of indirectly reducing ECM production is demonstrated to enhance tumor penetration and inhibit deep tumor glycolysis.


Subject(s)
Breast Neoplasms , Breast Neoplasms/drug therapy , Cell Line, Tumor , Edetic Acid , Female , Folic Acid , Glycolysis , Humans , Indocyanine Green/pharmacology , Lactic Acid , Liposomes
10.
Nature ; 603(7902): 610-615, 2022 03.
Article in English | MEDLINE | ID: mdl-35322253

ABSTRACT

The Fermi surface plays an important role in controlling the electronic, transport and thermodynamic properties of materials. As the Fermi surface consists of closed contours in the momentum space for well-defined energy bands, disconnected sections known as Fermi arcs can be signatures of unusual electronic states, such as a pseudogap1. Another way to obtain Fermi arcs is to break either the time-reversal symmetry2 or the inversion symmetry3 of a three-dimensional Dirac semimetal, which results in formation of pairs of Weyl nodes that have opposite chirality4, and their projections are connected by Fermi arcs at the bulk boundary3,5-12. Here, we present experimental evidence that pairs of hole- and electron-like Fermi arcs emerge below the Neel temperature (TN) in the antiferromagnetic state of cubic NdBi due to a new magnetic splitting effect. The observed magnetic splitting is unusual, as it creates bands of opposing curvature, which change with temperature and follow the antiferromagnetic order parameter. This is different from previous theoretically considered13,14 and experimentally reported cases15,16 of magnetic splitting, such as traditional Zeeman and Rashba, in which the curvature of the bands is preserved. Therefore, our findings demonstrate a type of magnetic band splitting in the presence of a long-range antiferromagnetic order that is not readily explained by existing theoretical ideas.

11.
Phys Rev Lett ; 128(3): 036402, 2022 Jan 21.
Article in English | MEDLINE | ID: mdl-35119899

ABSTRACT

The entanglement of charge density wave (CDW), superconductivity, and topologically nontrivial electronic structure has recently been discovered in the kagome metal AV_{3}Sb_{5} (A=K, Rb, Cs) family. With high-resolution angle-resolved photoemission spectroscopy, we study the electronic properties of CDW and superconductivity in CsV_{3}Sb_{5}. The spectra around K[over ¯] is found to exhibit a peak-dip-hump structure associated with two separate branches of dispersion, demonstrating the isotropic CDW gap opening below E_{F}. The peak-dip-hump line shape is contributed by linearly dispersive Dirac bands in the lower branch and a dispersionless flat band close to E_{F} in the upper branch. The electronic instability via Fermi surface nesting could play a role in determining these CDW-related features. The superconducting gap of ∼0.4 meV is observed on both the electron band around Γ[over ¯] and the flat band around K[over ¯], implying the multiband superconductivity. The finite density of states at E_{F} in the CDW phase is most likely in favor of the emergence of multiband superconductivity, particularly the enhanced density of states associated with the flat band. Our results not only shed light on the controversial origin of the CDW, but also offer insights into the relationship between CDW and superconductivity.

12.
Bioresour Technol ; 344(Pt B): 126174, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34737047

ABSTRACT

To investigate the effect of hemicellulose removal on subsequent choline chloride and lactic acid (ChCl-LA) based deep eutectic solvent (DES) extraction of wheat straw lignin, ChCL-LA of DES and hot water presoaking pretreatments were used for hemicellulose prehydrolysis. Both presoakings led to a significant hemicellulose removal and introduced morphological changes on fiber cell wall surface. DES presoaking also instigated ether bonds cleavage between lignin and hemicellulose and selectively removed lignin in compound middle lamella (CML) and cell corner (CC) leading to cell wall disruption and swelling which facilitated lignin extraction. Hot water presoaking removed more hemicellulose and caused a migration of lignin to fibers surface, but did not improve subsequent lignin extraction. This study demonstrated that a two-stage DES treatment method, presoaking at room temperature followed by extracting at an elevated temperature, is a viable process to produce high yield and purity of lignin.


Subject(s)
Lignin , Triticum , Carbohydrates , Deep Eutectic Solvents , Solvents
13.
ACS Omega ; 6(49): 34129-34136, 2021 Dec 14.
Article in English | MEDLINE | ID: mdl-34926960

ABSTRACT

Green synthesis of lignin-based carbon materials can accelerate the development of energy storage and conversion in supercapacitors. In this work, hierarchical graphenelike carbon was prepared by alkali lignin (AL) pyrolysis at a high temperature of 1700 °C. Accompanied by metal salt catalysis and a nitrogen hybridization reaction, a unique nanostructure of graphitized ALC was obtained with both a well-ordered 2D sheet lamellar structure and a uniform bowl-like porous structure. ALC exhibited a graphenelike lattice structure, a BET specific surface area of 1190 m2·g-1, and excellent electrochemical performance (104 F·g-1/0.5 A·g-1). The study offers a prospective way to the high-value application of industrial lignin in supercapacitor electrode materials.

14.
Leuk Res Rep ; 16: 100258, 2021.
Article in English | MEDLINE | ID: mdl-34367907

ABSTRACT

Acute promyelocytic leukemia (APL) is a highly curable hematology malignancy. The major factor influence prognosis of APL is early deaths (ED) during the course of induction therapy, especially in high-risk APL. Therefore, effective reduction of white blood cells and correction of coagulation abnormalities are the key points of treatment for high-risk APL. Due to COVID19 pandemic in China since Jan 2020, some patients with hematologic malignancies suspected of COVID-19 infection had been isolated and traditional intravenous chemotherapy drugs is not available in isolated wards. We had explored a regimen of an oral etoposide to reduce the tumor burden for high-risk APL and dual induction with retinoic acid (ATRA) and oral arsenic realgar-Indigo nautralis formula (RIF), and finally two cases of high-risk APL patients received complete remission in one month. It is indicated that pure oral induction regimen: oral etoposide, ATRA and RIF provides a novel therapy in outpatient clinics.

15.
Micromachines (Basel) ; 12(6)2021 May 26.
Article in English | MEDLINE | ID: mdl-34073636

ABSTRACT

Microfluidic chips and optical elements can be fabricated based on the nonlinear photosensitivity in photo-thermo-refractive (PTR) glass by controlling the growth of nanocrystals in the femtosecond (fs) laser-irradiated region. Here, we focus on CeO2 and Sb2O3 that play important roles in UV irradiation, experimentally investigate the effects of the dopants on the nonlinear photochemical process in PTR glass triggered by fs Gaussian-Bessel beams. The results show that the generation of Ag0 atoms and the Ag nanoparticles can be improved by CeO2 and Sb2O3 co-doping. Besides, each multivalent ion in PTR glass possibly participates in the electron transfer processes and contributes to the generation of Ag0 atoms. Finally, X-ray diffraction analysis reveals the precipitation of NaF nanocrystals with an average size of 10 to 12 nm after laser irradiation and thermal treatment, which is unrelated to the dopants.

16.
Analyst ; 146(14): 4674-4682, 2021 Jul 21.
Article in English | MEDLINE | ID: mdl-34190228

ABSTRACT

With the existing medical diagnostic technology, the diagnosis of atherosclerosis (AS) is mainly focused on the later stage of AS development rather than plaque imaging in the period before plaque formation. It is impractical to apply the existing theoretical methods for the purpose of early detection of AS. Herein, this study uses a naphthalimide-based fluorescent probe for recognition of cellular reactive oxygen species (ROS). A platelet membrane (Mp) with foam cell targeting was wrapped around the probes to prepare two vesicle structures TBNG@Mp and GNTB@Mp. The animal experiment results show that the screened nano-detection system TBNG@Mp could accumulate in the thoracic aorta of early AS rats. Under the effect of intracellular ROS, fluorescence signals can be observed. In addition, acute biological toxicity was not observed in pathological sections. Therefore, the foam cell targeting system TBNG@Mp with acceptable biocompatibility can realize the detection of AS one to two decades in advance as well as has a good application prospect.


Subject(s)
Atherosclerosis , Animals , Atherosclerosis/diagnosis , Early Diagnosis , Fluorescent Dyes , Naphthalimides , Rats , Reactive Oxygen Species
17.
Nat Commun ; 12(1): 3129, 2021 May 25.
Article in English | MEDLINE | ID: mdl-34035305

ABSTRACT

Kagome-lattices of 3d-transition metals hosting Weyl/Dirac fermions and topological flat bands exhibit non-trivial topological characters and novel quantum phases, such as the anomalous Hall effect and fractional quantum Hall effect. With consideration of spin-orbit coupling and electron correlation, several instabilities could be induced. The typical characters of the electronic structure of a kagome lattice, i.e., the saddle point, Dirac-cone, and flat band, around the Fermi energy (EF) remain elusive in magnetic kagome materials. We present the experimental observation of the complete features in ferromagnetic kagome layers of YMn6Sn6 helically coupled along the c-axis, by using angle-resolved photoemission spectroscopy and band structure calculations. We demonstrate a Dirac dispersion near EF, which is predicted by spin-polarized theoretical calculations, carries an intrinsic Berry curvature and contributes to the anomalous Hall effect in transport measurements. In addition, a flat band and a saddle point with a high density of states near EF are observed. These multi-sets of kagome features are of orbital-selective origin and could cause multi-orbital magnetism. The Dirac fermion, flat band and saddle point in the vicinity of EF open an opportunity in manipulating the topological properties in magnetic materials.

18.
Micromachines (Basel) ; 12(3)2021 Feb 26.
Article in English | MEDLINE | ID: mdl-33652965

ABSTRACT

Antireflection and superhydrophilicity performance are desirable for improving the properties of electronic devices. Here, we experimentally provide a strategy of femtosecond laser preparation to create micro-nanostructures on the graphite surface in an air environment. The modified graphite surface is covered with abundant micro-nano structures, and its average reflectance is measured to be 2.7% in the ultraviolet, visible and near-infrared regions (250 to 2250 nm). The wettability transformation of the surface from hydrophilicity to superhydrophilicity is realized. Besides, graphene oxide (GO) and graphene are proved to be formed on the sample surface. This micro-nanostructuring method, which demonstrates features of high efficiency, high controllability, and hazardous substances zero discharge, exhibits the application for functional surface.

19.
J Mater Chem B ; 9(5): 1424-1431, 2021 02 07.
Article in English | MEDLINE | ID: mdl-33465212

ABSTRACT

The poor penetration of solid tumors hinders the development of hunger therapy represented by glucose oxidase (GOx). To address this limitation, we have constructed a GOx/Dex@ZIF-TA nanosystem consisting of tannic acid (TA), carrier ZIF-8, encapsulated GOx and dexamethasone (Dex). In this nanosystem, the loaded Dex can not only expand the pores of the nucleus to promote GOx to enter the nucleus, addressing the shortcomings of short life of reactive oxygen species, but also inhibit the production of collagen to reshape the tumor microenvironment and inhibit lung metastasis. In vivo experiments proved that Dex could inhibit the production of collagen, which increased the accumulation and penetration of the tumor tissues and inhibited lung metastasis. In addition, cell experiments showed that Dex could also enlarge the nuclear pores of the nucleus and promote the entry of drugs into the nucleus. More importantly, Dex is a broad anti-inflammatory drug, and the results of this study should be easily transformed to achieve clinical benefits. Together, this work provided a way to address the limitations of hunger distribution in tumor tissues.


Subject(s)
Glucose Oxidase/metabolism , Humans , Neoplasm Metastasis , Tumor Microenvironment
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