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1.
Front Immunol ; 15: 1369376, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38638426

RESUMO

Introduction: Interleukin-2 (IL-2) is one of the first cytokines to be discovered as an immune agonist for cancer immunotherapy. Biased IL-2 variants had been discovered to eliminate Treg activation or enhance the tumor specific T cell cytotoxicity. However, all the biased IL-2 variants pose the risk to overstimulate immune response at a low-dose range. Here, we introduce a novel dual-MOA bispecific PD-1-IL-2v molecule with great anti-tumor efficacy in a high dosed manner. Methods: The novel IL-2 variant was designed by structural truncation and shuffling. The single armed bispecific PD-1-IL-2v molecule and IL-2v were studied by immune cell activations in vitro and in vivo and anti-tumor efficacy in mouse model. Results and discussion: The IL-2 variant in this bispecific antibody only binds to IL-2Rßγ complex in a fast-on/off manner without α, ß or γ single receptor binding. This IL-2v mildly activates T and NK cells without over stimulation, meanwhile it diminishes Treg activation compared to the wild type IL-2. This unique bispecific molecule with "ßγ-only" IL-2v can not only "in-cis" stimulate and expand CD8 T and NK cells moderately without Treg activation, but also block the PD-1/L1 interaction at a similar dose range with monoclonal antibody.


Assuntos
Interleucina-2 , Receptor de Morte Celular Programada 1 , Animais , Camundongos , Interleucina-2/genética , Interleucina-2/metabolismo , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/metabolismo , Linhagem Celular Tumoral , Linfócitos T , Células Matadoras Naturais
2.
Zool Res ; 45(3): 478-491, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38682430

RESUMO

Acetaminophen (APAP), the most frequently used mild analgesic and antipyretic drug worldwide, is implicated in causing 46% of all acute liver failures in the USA and between 40% and 70% in Europe. The predominant pharmacological intervention approved for mitigating such overdose is the antioxidant N-acetylcysteine (NAC); however, its efficacy is limited in cases of advanced liver injury or when administered at a late stage. In the current study, we discovered that treatment with a moderate intensity static magnetic field (SMF) notably reduced the mortality rate in mice subjected to high-dose APAP from 40% to 0%, proving effective at both the initial liver injury stage and the subsequent recovery stage. During the early phase of liver injury, SMF markedly reduced APAP-induced oxidative stress, free radicals, and liver damage, resulting in a reduction in multiple oxidative stress markers and an increase in the antioxidant glutathione (GSH). During the later stage of liver recovery, application of vertically downward SMF increased DNA synthesis and hepatocyte proliferation. Moreover, the combination of NAC and SMF significantly mitigated liver damage induced by high-dose APAP and increased liver recovery, even 24 h post overdose, when the effectiveness of NAC alone substantially declines. Overall, this study provides a non-invasive non-pharmaceutical tool that offers dual benefits in the injury and repair stages following APAP overdose. Of note, this tool can work as an alternative to or in combination with NAC to prevent or minimize liver damage induced by APAP, and potentially other toxic overdoses.


Assuntos
Acetaminofen , Analgésicos não Narcóticos , Doença Hepática Induzida por Substâncias e Drogas , Overdose de Drogas , Acetaminofen/toxicidade , Animais , Camundongos , Analgésicos não Narcóticos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Masculino , Campos Magnéticos , Acetilcisteína/uso terapêutico , Acetilcisteína/farmacologia
3.
J Pediatr Orthop ; 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38533533

RESUMO

BACKGROUND: The shape of the labrum is strongly correlated with outcomes of developmental dysplasia of the hip (DDH). Magnetic resonance imaging (MRI) is the generally preferred imaging technique for observing the labrum. PURPOSE: We aimed to find a correlation between the labrum shape and anterior-posterior (AP) pelvic measurements in children with DDH. METHODS: Preoperative AP pelvic x-ray radiographs and MRI of patients with DDH from January 2019 to December 2021 were retrospectively collected and divided into three groups by labrum shape on MRI: everted, partly inverted, and inverted. The acetabular length ratio (RAL) in patients with unilateral DDH and the ratio of acetabular length to interpedicular distance (RALI) in all patients were calculated. T-tests were used to analyze differences between the groups. Receiver operating characteristic curve (ROC) analysis was performed between the everted group and the partly inverted and inverted groups. RESULTS: We found significant differences in RAL between the everted and partly inverted groups, everted and inverted groups, and everted and combined groups. The ROC analysis showed that the best cutoff value for RAL was 0.945 between the everted and combined groups, with an area under the curve (AUC) of 88.4%. The sensitivity at the best RAL value was 0.783, and the specificity was 0.887. Moreover, we observed a significant difference in RALI between the everted, partly inverted, and inverted groups, as well as between the everted and combined groups. The optimal cutoff value for RALI between the everted and combined groups was 0.575, with an AUC of 74.5%. The sensitivity at the best RALI value was 0.765, and the specificity was 0.674. CONCLUSION: The RAL or RALI values on pelvic AP radiographs can be used to predict the shape of the labrum. LEVEL OF EVIDENCE: III.

4.
BMC Pregnancy Childbirth ; 24(1): 164, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38408955

RESUMO

BACKGROUND: The causes of some stillbirths are unclear, and additional work must be done to investigate the risk factors for stillbirths. OBJECTIVE: To apply the International Classification of Disease-10 (ICD-10) for antepartum stillbirth at a referral center in eastern China. METHODS: Antepartum stillbirths were grouped according to the cause of death according to the International Classification of Disease-10 (ICD-10) criteria. The main maternal condition at the time of antepartum stillbirth was assigned to each patient. RESULTS: Antepartum stillbirths were mostly classified as fetal deaths of unspecified cause, antepartum hypoxia. Although more than half of the mothers were without an identified condition at the time of the antepartum stillbirth, where there was a maternal condition associated with perinatal death, maternal medical and surgical conditions and maternal complications during pregnancy were most common. Of all the stillbirths, 51.2% occurred between 28 and 37 weeks of gestation, the main causes of stillbirth at different gestational ages also differed. Autopsy and chromosomal microarray analysis (CMA) were recommended in all stillbirths, but only 3.6% received autopsy and 10.5% underwent chromosomal microarray analysis. CONCLUSIONS: The ICD-10 is helpful in classifying the causes of stillbirths, but more than half of the stillbirths in our study were unexplained; therefore, additional work must be done. And the ICD-10 score may need to be improved, such as by classifying stillbirths according to gestational age. Autopsy and CMA could help determine the cause of stillbirth, but the acceptance of these methods is currently low.


Assuntos
Classificação Internacional de Doenças , Natimorto , Gravidez , Feminino , Humanos , Natimorto/epidemiologia , Estudos Retrospectivos , Morte Fetal/etiologia , Encaminhamento e Consulta , Causas de Morte
5.
Small ; 20(17): e2307728, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38263806

RESUMO

Herein, the structure of integrated M3D inverters are successfully demonstrated where a chemical vapor deposition (CVD) synthesized monolayer WSe2 p-type nanosheet FET is vertically integrated on top of CVD synthesized monolayer MoS2 n-type film FET arrays (2.5 × 2.5 cm) by semiconductor industry techniques, such as transfer, e-beam evaporation (EBV), and plasma etching processes. A low temperature (below 250 °C) is employed to protect the WSe2 and MoS2 channel materials from thermal decomposition during the whole fabrication process. The MoS2 NMOS and WSe2 PMOS device fabricated show an on/off current ratio exceeding 106 and the integrated M3D inverters indicate an average voltage gain of ≈9 at VDD = 2 V. In addition, the integrated M3D inverter demonstrates an ultra-low power consumption of 0.112 nW at a VDD of 1 V. Statistical analysis of the fabricated inverters devices shows their high reliability, rendering them suitable for large-area applications. The successful demonstration of M3D inverters based on large-scale 2D monolayer TMDs indicate their high potential for advancing the application of 2D TMDs in future integrated circuits.

6.
ACS Appl Mater Interfaces ; 16(1): 1705-1711, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38145463

RESUMO

Two-dimensional (2D) metal nitrides have garnered significant interest due to their potential applications in future electronics and quantum systems. However, the synthesis of such materials with sufficient uniformity and at relevant scales remains an unaddressed challenge. This study demonstrates the potential of confined growth to control and enhance the morphology of 2D metal nitrides. By restricting the reaction volume of vapor-liquid-solid reactions, an enhanced precursor concentration was achieved that reduces the nucleation density, resulting in larger grain sizes and suppression of multilayer growth. Detailed characterization reveals the importance of balancing the energetic and kinetic aspects of tungsten nitride formation toward this ability. The introduction of a promoter enabled the realization of large-scale, single-layer tungsten nitride with a uniform and high interfacial quality. Finally, our advance in morphology control was applied to the production of edge-enriched 2D tungsten nitrides with significantly enhanced hydrogen evolution ability, as indicated by an unprecedented Tafel slope of 55 mV/dec.

7.
Nano Lett ; 24(1): 67-73, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38149785

RESUMO

Two-dimensional transition metal nitrides offer intriguing possibilities for achieving novel electronic and mechanical functionality owing to their distinctive and tunable bonding characteristics compared to other 2D materials. We demonstrate here the enabling effects of strong bonding on the morphology and functionality of 2D tungsten nitrides. The employed bottom-up synthesis experienced a unique substrate stabilization effect beyond van-der-Waals epitaxy that favored W5N6 over lower metal nitrides. Comprehensive structural and electronic characterization reveals that monolayer W5N6 can be synthesized at large scale and shows semimetallic behavior with an intriguing indirect band structure. Moreover, the material exhibits exceptional resilience against mechanical damage and chemical reactions. Leveraging these electronic properties and robustness, we demonstrate the application of W5N6 as atomic-scale dry etch stops that allow the integration of high-performance 2D materials contacts. These findings highlight the potential of 2D transition metal nitrides for realizing advanced electronic devices and functional interfaces.

8.
Huan Jing Ke Xue ; 44(12): 6508-6517, 2023 Dec 08.
Artigo em Chinês | MEDLINE | ID: mdl-38098379

RESUMO

To investigate the seasonal variation, health risks, and potential sources of polycyclic aromatic hydrocarbons(PAHs) in PM2.5 in the Lüliang area, PM2.5 samples were collected in Lishi District(downtown area) and Xiaoyi City(suburban area) from October 23, 2018 to July 1, 2019, and the concentrations of 14 PAHs were determined using gas chromatography-mass spectrometry(GC-MS). The annual average concentration of PAHs was 95.50 ng·m-3, and the concentration of 5-6 ring PAHs was mainly(49.7%), with 3 ring PAHs accounting for a relatively low proportion(8.3%).The concentration of PAHs in Lüliang City showed a seasonal pattern of winter>autumn>spring>summer. The results of the ILCRs model and Monte Carlo simulation showed that the toxicity of PAHs in Lüliang City followed the rule of adults>youth>children. Except in summer, the ILCRs values in the Lishi area were between 10-6 and 10-4, much higher than those in Xiaoyi City, indicating that there was a high potential risk of polycyclic aromatic hydrocarbons in the urban area. Through the characteristic ratio method and positive matrix factorization(PMF), it was shown that the PAHs in Lüliang City were mainly from the combustion of coal and biomass(61.9%) and vehicle exhaust emissions(38.1%). Based on the backward trajectory and potential source factor contribution analysis model, it was determined that the potential sources of PAHs in Lüliang City were mainly distributed in southern Shanxi, northern Shaanxi, and western Inner Mongolia.


Assuntos
Poluentes Atmosféricos , Hidrocarbonetos Policíclicos Aromáticos , Adulto , Criança , Adolescente , Humanos , Poluentes Atmosféricos/análise , Material Particulado/análise , Monitoramento Ambiental/métodos , Emissões de Veículos/análise , Estações do Ano , Medição de Risco , China , Hidrocarbonetos Policíclicos Aromáticos/análise , Carvão Mineral/análise
9.
Int J Speech Lang Pathol ; : 1-9, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37908078

RESUMO

Purpose: The aim of this pilot study was to explore the efficacy of an intensive 3 week water resistance phonation (WRP) therapy program for people with presbyphonia.Method: Participants included 13 people with presbyphonia who received intensive WRP therapy. All participants completed eight sessions of therapy over 3 weeks. Auditory perceptual ratings, and acoustic and aerodynamic assessments were performed before and after treatment. Participants also completed the voice-related quality of life questionnaire before and after the treatment.Result: After 3 weeks of intensive voice therapy, significant improvements were demonstrated in acoustic, aerodynamic, and auditory perceptual parameters, as well as patient perceptions of voice-related quality of life. Acoustically, it was found there were significant decreases in shimmer (p = 0.019), noise-to-harmonic ratio (p = 0.016), and smoothed cepstral peak prominence (p = 0.001). Perceptually, the clients with presbyphonia showed significant reductions in the ratings of the overall grade, roughness, asthenia, and strain. Moreover, there was a significant increase in the total score of the Mandarin version of the Voice-Related Quality of Life measure post-therapy.Conclusion: The investigation provides preliminary evidence that people with presbyphonia can improve their vocal function and voice-related quality of life through intensive WRP therapy within a short period of time.

10.
Org Biomol Chem ; 21(47): 9341-9345, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37987693

RESUMO

A visible light-enabled cascade cyclization strategy is disclosed with concomitant phosphorylation and heterocycle construction. It provides a novel and environmentally benign approach for accessing tetrahydroindolizine-containing phosphonates under metal-free conditions. Mechanistic studies revealed that phosphinoyl radicals were generated from H-phosphonates via a HAT process.

11.
J Org Chem ; 88(23): 16547-16555, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37971809

RESUMO

A photocatalytic three-component reaction of a nitroarene, a thiophenol, and a ketone for the synthesis of multifunctional diaryl sulfides was reported using a nitro group as the nitrogen source and thiophenol as the sulfur source. Thiophenol also serves as a proton donor to reduce nitroarene to arylamine as a key intermediate for the formation of C-N and C-S bonds. Good functional group tolerance and mild reaction conditions make this method have practical synthetic value for diversified multifunctional diaryl sulfides.

12.
Laryngoscope Investig Otolaryngol ; 8(4): 980-988, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37621265

RESUMO

Objectives: This study developed the Mandarin Chinese version of the Aging Voice Index (AVI), with preliminary validation of the scale for potential clinical applications. Study Design: Scale development. Methods: The experimental procedure involved: (1) cross-cultural adaptation of the original AVI into the Mandarin Chinese version (CAVI); (2) evaluation by expert panel; (3) back translation; (4) pilot testing; (5) development of the final CAVI; (6) scale validation with 68 older adults of 60-89 years old (29 females and 39 males), 34 with voice disorders and 34 age-matched with normal voice. Internal consistency reliability, test-retest reliability, content validity, criterion-related validity, and discriminatory ability (diagnostic accuracy) of the CAVI were evaluated. Results: There were high internal consistency (Cronbach's alpha = 0.9733), high test-retest reliability (intraclass correlation coefficient = 0.9578, p < 0.01), high content validity (content validity index = 0.9710), high criterion-related validity (Pearson's r = 0.9439, p < 0.01 between CAVI and Voice Handicap Index-10; r = 0.8070, p < 0.01 between CAVI and voice-related quality of life [V-RQOL]), and significant difference in CAVI scores between the two groups with huge effect size (t(34.69) = -11.59, Cohen's d = 2.81, p < 0.001). Receiver operating characteristic analysis revealed a high diagnostic accuracy of the CAVI, with an area under the curve of 0.9974 (p < 0.001) and a cut-off score of 12.0 with 100% sensitivity and 97.1% specificity. Conclusion: Our findings suggested that the CAVI could be a reliable and valid standardized self-assessment questionnaire tool for clinical evaluation of the impact of voice problems specifically for Mandarin-speaking older adults. Further studies should explore a full-scale validation of the CAVI for being a standard clinical tool, including for older adults in Mainland China. Level of evidence: 3b (case-control study).

13.
Int Orthop ; 2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37442823

RESUMO

PURPOSE: Hip vessel examination provides key information on many hip-related pediatric diseases, and it has an important role in the evaluation of femoral head (FH) blood supply and diagnosis of avascular necrosis (AVN). The aim of this study was to investigate the feasibility of MR-enhanced high-resolution three-dimensional water-selective cartilage (3D-WATSc) sequence in visualizing the vessels of the hip joint in children. PATIENTS AND METHODS: Children with hip disease were randomly enrolled prospectively at our hospital from January 2021 to August 2022. We performed our institution's hip MRI protocol and enhanced high-resolution 3D-WATSc sequence. The 3D-WATSc images were reconstructed and analyzed, and images of the normal hip were categorized into grades 0-3. The abnormal hip images were compared with those of the normal side using the χ2 test. RESULTS: Twenty-four patients with unilateral hip abnormalities were included in this study. The cartilaginous vascular canal and ossification centre vessels of normal FHs were observed in 18 patients (75%) and met the grade 3 standard. An abnormal cartilaginous canal was observed in 16 patients (67%); meanwhile, 18 patients (75%) had abnormal extrachondral vessels. Comparison of high-resolution 3D-WATSc images with those of the normal side provided effective abnormal vascular information in 95.8% of patients. CONCLUSIONS: Enhanced high-resolution 3D-WATSc can visualize the blood vessels of the hip in children. This may provide a new method for the vascular study of various pediatric hip diseases.

14.
J Ethnopharmacol ; 314: 116635, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37182675

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Uncaria rhynchophylla (Miq.) Miq. ex Havil. is a plant species that is routinely devoted in traditional Chinese medicine to treat central nervous system disorders. Rhynchophylline (Rhy), a predominant alkaloid isolated from Uncaria rhynchophylla (Miq.) Miq. ex Havil., has been demonstrated to reverse methamphetamine-induced (METH-induced) conditioned place preference (CPP) effects in mice, rats and zebrafish. The precise mechanism is still poorly understood, thus further research is necessary. AIM OF STUDY: This study aimed to investigate the role of miRNAs in the inhibitory effect of Rhy on METH dependence. MATERIALS AND METHODS: A rat CPP paradigm and a PC12 cell addiction model were established. Microarray assays were used to screen and identify the candidate miRNA. Behavioral assessment, real-time PCR, dual-luciferase reporter assay, western blotting, stereotaxic injection of antagomir/agomir and cell transfection experiments were performed to elucidate the effect of the candidate miRNA and intervention mechanism of Rhy on METH dependence. RESULTS: Rhy successfully reversed METH-induced CPP effect and the upregulated miR-181a-5p expression in METH-dependent rat hippocampus and PC12 cells. Moreover, suppression of miR-181a-5p by antagomir 181a reversed METH-induced CPP effect. Meanwhile, overexpression of miR-181a-5p by agomir 181a in combination with low-dose METH (0.5 mg/kg) elicited a significant CPP effect, which was blocked by Rhy through inhibiting miR-181a-5p. Finally, the result demonstrated that miR-181a-5p exerted its regulatory role by targeting γ-aminobutyric acid A receptor α1 (GABRA1) both in vivo and in vitro. CONCLUSION: This finding reveals that Rhy inhibits METH dependence via modulating the miR-181a-5p/GABRA1 axis, which may be a promising target for treatment of METH dependence.


Assuntos
Transtornos Relacionados ao Uso de Anfetaminas , Metanfetamina , MicroRNAs , Ratos , Camundongos , Animais , Receptores de GABA , Antagomirs , Peixe-Zebra/genética , Transtornos Relacionados ao Uso de Anfetaminas/genética , Transtornos Relacionados ao Uso de Anfetaminas/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Metanfetamina/farmacologia
15.
Micromachines (Basel) ; 14(5)2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37241683

RESUMO

Graphene-an outstanding low-dimensional material-exhibited many physics behaviors that are unknown over the past two decades, e.g., exceptional matter-light interaction, large light absorption band, and high charge carrier mobility, which can be adjusted on arbitrary surfaces. The deposition approaches of graphene on silicon to form the heterostructure Schottky junctions was studied, unveiling new roadmaps to detect the light at wider-ranged absorption spectrums, e.g., far-infrared via excited photoemission. In addition, heterojunction-assisted optical sensing systems enable the active carriers' lifetime and, thereby, accelerate the separation speed and transport, and then they pave new strategies to tune high-performance optoelectronics. In this mini-review, an overview is considered concerning recent advancements in graphene heterostructure devices and their optical sensing ability in multiple applications (ultrafast optical sensing system, plasmonic system, optical waveguide system, optical spectrometer, or optical synaptic system) is discussed, in which the prominent studies for the improvement of performance and stability, based on the integrated graphene heterostructures, have been reported and are also addressed again. Moreover, the pros and cons of graphene heterostructures are revealed along with the syntheses and nanofabrication sequences in optoelectronics. Thereby, this gives a variety of promising solutions beyond the ones presently used. Eventually, the development roadmap of futuristic modern optoelectronic systems is predicted.

16.
Zookeys ; 1154: 159-222, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37213701

RESUMO

In this study, 21 species of the leaf-beetle genus Aplosonyx in China are described, including three new species, Aplosonyxancorellasp. nov., Aplosonyxnigricornissp. nov. and Aplosonyxwudangensissp. nov., and 1 new record, Aplosonyxduvivieri Jacoby, 1900. Additionally, Aplosonyxancorafulvescens Chen, 1964 is elevated to species. A key to the Chinese species of Aplosonyx is provided.

17.
ACS Nano ; 17(11): 10280-10290, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37218668

RESUMO

Although molecular piezoelectric materials are ideal constituents for next-generation electronic microdevices, their weak piezoelectric coefficients which restrict their practical applications need to be enhanced by some strategies. Herein, a series of d-phenylalanine derivatives are synthesized and an increased molecular piezoelectric coefficient of their assemblies is achieved by acid doping. The acid doping can increase the asymmetric distribution of charges in the molecules and in turn molecular polarizability, leading to the enhanced molecular piezoelectricity of assemblies. The effective piezoelectric coefficients can be promoted up to 38.5 pm V-1 and four times those without doping, which is also higher than those obtained by the reported methods. Moreover, the piezoelectric energy harvesters can generate voltage up to 3.4 V and current up to 80 nA. This practical strategy can enhance piezoelectric coefficients without varying the crystal structures of the assemblies, which may inspire future molecular design of organic functional materials.

18.
Macromol Biosci ; 23(10): e2300082, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37219022

RESUMO

Bacterial infections and oxidative damage caused by various reactive oxygen species (ROS) pose a significant threat to human health. It is highly desirable to find an ideal biomaterial system with broad spectrum antibacterial and antioxidant capabilities. A new supramolecular antibacterial and antioxidant composite hydrogel made of chiral L-phenylalanine-derivative (LPFEG) as matrix and Mxene (Ti3 C2 Tx ) as filler material is presented. The noncovalent interactions (H-bonding and π-π interactions) in between LPFEG and Mxene and the inversion of LPFEG chirality are verified by Fourier transform infrared and circular dichroism spectroscopy. The composite hydrogels show improved mechanical properties revealed by rheological analysis. The composite hydrogel system exhibits photothermal conversion efficiency (40.79%), which enables effective photothermal broad-spectrum antibacterial activities against both Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli, Pseudomonas aeruginosa) bacteria. Furthermore, the Mxene also enables the composite hydrogel to exhibit excellent antioxidant activity by efficiently scavenging free radicals like DPPH•, ABTS•+, and •OH. These results indicate that the Mxene-based chiral supramolecular composite hydrogel, with improved rheological, antibacterial, and antioxidant properties has a great potential for biomedical applications.

19.
Nat Commun ; 14(1): 2228, 2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37076531

RESUMO

The spacetime light cone is central to the definition of causality in the theory of relativity. Recently, links between relativistic and condensed matter physics have been uncovered, where relativistic particles can emerge as quasiparticles in the energy-momentum space of matter. Here, we unveil an energy-momentum analogue of the spacetime light cone by mapping time to energy, space to momentum, and the light cone to the Weyl cone. We show that two Weyl quasiparticles can only interact to open a global energy gap if they lie in each other's energy-momentum dispersion cones-analogous to two events that can only have a causal connection if they lie in each other's light cones. Moreover, we demonstrate that the causality of surface chiral modes in quantum matter is entangled with the causality of bulk Weyl fermions. Furthermore, we identify a unique quantum horizon region and an associated 'thick horizon' in the emergent causal structure.

20.
ACS Nano ; 17(7): 6275-6291, 2023 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-36946387

RESUMO

Revascularization plays a critical role in the healing of diabetic wounds. Accumulation of advanced glycation end products (AGEs) and refractory multidrug resistant bacterial infection are the two major barriers to revascularization, directly leading to impaired healing of diabetic wounds. Here, an artfully designed chiral gel dressing is fabricated (named as HA-LM2-RMR), which consists of l-phenylalanine and cationic hexapeptide coassembled helical nanofibers cross-linked with hyaluronic acid via hydrogen bonding. This chiral gel possesses abundant chiral and cationic sites, not only effectively reducing AGEs via stereoselective interaction but also specifically killing multidrug resistant bacteria rather than host cells since cationic hexapeptides selectively interact with negatively charged microbial membrane. Surprisingly, the HA-LM2-RMR fibers present an attractive ability to activate sprouted angiogenesis of Human Umbilical Vein Endothelial Cells by upregulating VEGF and OPA1 expression. In comparison with clinical Prontosan Wound Gel, the HA-LM2-RMR gel presents superior healing efficiency in the infected diabetic wound with respect to angiogenesis and re-epithelialization, shortening the healing period from 21 days to 14 days. These findings for chiral wound dressing provide insights for the design and construction of diabetic wound dressings that target revascularization, which holds great potential to be utilized in tissue regenerative medicine.


Assuntos
Diabetes Mellitus , Células Endoteliais , Humanos , Cicatrização , Bandagens , Peptídeos/farmacologia , Produtos Finais de Glicação Avançada/farmacologia
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