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1.
Phys Rev Lett ; 133(4): 046503, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39121416

RESUMO

The kagome spin ice can host frustrated magnetic excitations by flipping its local spin. Under an inelastic tunneling condition, the tip in a scanning tunneling microscope can flip the local spin, and we apply this technique to kagome metal HoAgGe with a long-range ordered spin ice ground state. Away from defects, we discover a pair of pronounced dips in the local tunneling spectrum at symmetrical bias voltages with negative intensity values, serving as a striking inelastic tunneling signal. This signal disappears above the spin ice formation temperature and has a dependence on the magnetic fields, demonstrating its intimate relation with the spin ice magnetism. We provide a two-level spin-flip model to explain the tunneling dips considering the spin ice magnetism under spin-orbit coupling. Our results uncover a local emergent excitation of spin ice magnetism in a kagome metal, suggesting that local electrical field induced spin flip climbs over a barrier caused by spin-orbital locking.

2.
Nature ; 632(8026): 775-781, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39169248

RESUMO

Superconductivity involving finite-momentum pairing1 can lead to spatial-gap and pair-density modulations, as well as Bogoliubov Fermi states within the superconducting gap. However, the experimental realization of their intertwined relations has been challenging. Here we detect chiral kagome superconductivity modulations with residual Fermi arcs in KV3Sb5 and CsV3Sb5 using normal and Josephson scanning tunnelling microscopy down to 30 millikelvin with a resolved electronic energy difference at the microelectronvolt level. We observe a U-shaped superconducting gap with flat residual in-gap states. This gap shows chiral 2a × 2a spatial modulations with magnetic-field-tunable chirality, which align with the chiral 2a × 2a pair-density modulations observed through Josephson tunnelling. These findings demonstrate a chiral pair density wave (PDW) that breaks time-reversal symmetry. Quasiparticle interference imaging of the in-gap zero-energy states reveals segmented arcs, with high-temperature data linking them to parts of the reconstructed vanadium d-orbital states within the charge order. The detected residual Fermi arcs can be explained by the partial suppression of these d-orbital states through an interorbital 2a × 2a PDW and thus serve as candidate Bogoliubov Fermi states. In addition, we differentiate the observed PDW order from impurity-induced gap modulations. Our observations not only uncover a chiral PDW order with orbital selectivity but also show the fundamental space-momentum correspondence inherent in finite-momentum-paired superconductivity.

3.
Nat Mater ; 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39198714

RESUMO

Superconductivity and magnetism are often antagonistic in quantum matter, although their intertwining has long been considered in frustrated-lattice systems. Here we utilize scanning tunnelling microscopy and muon spin resonance to demonstrate time-reversal symmetry-breaking superconductivity in kagome metal Cs(V, Ta)3Sb5, where the Cooper pairing exhibits magnetism and is modulated by it. In the magnetic channel, we observe spontaneous internal magnetism in a fully gapped superconducting state. Under the perturbation of inverse magnetic fields, we detect a time-reversal asymmetrical interference of Bogoliubov quasi-particles at a circular vector. At this vector, the pairing gap spontaneously modulates, which is distinct from pair density waves occurring at a point vector and consistent with the theoretical proposal of an unusual interference effect under time-reversal symmetry breaking. The correlation between internal magnetism, Bogoliubov quasi-particles and pairing modulation provides a chain of experimental indications for time-reversal symmetry-breaking kagome superconductivity.

4.
Biomedicines ; 12(8)2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39200168

RESUMO

BACKGROUND: Cognitive impairment is a prevalent complication of type 2 diabetes, influenced significantly by various dietary patterns. High-carbohydrate diets (HCDs) are commonly consumed nowadays; however, the specific impact of HCDs on cognitive function in diabetes remains unclear. METHODS: The objective of this study was to investigate whether an HCD has effects on cognition in diabetes. Eight-week-old diabetic (db/db) mice and wild-type (WT) mice underwent a twelve-week dietary intervention, including a normal diet (ND), an HCD, or a high-fat diet (HFD). Following this, behavioral tests were conducted, and related hippocampal pathology was evaluated. RESULTS: Our results demonstrated that an HCD exacerbated cognitive decline in db/db mice compared to an ND. Additionally, an HCD increased amyloid-ß burden and expression of ß-site APP cleaving enzyme-1. An HCD was also found to promote the phosphorylation of tau protein via the PI3K/Akt/GSK-3ß pathway. Furthermore, an HCD markedly induced neuroinflammation and increased the quantity of microglia and astrocytes. However, these damages induced by an HCD were less severe than those caused by an HFD. CONCLUSIONS: Collectively, our findings indicate that a high intake of carbohydrates can have an adverse impact on cognitive function in diabetes.

5.
Nat Commun ; 15(1): 7052, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39147740

RESUMO

The interplay of topology, magnetism, and correlations gives rise to intriguing phases of matter. In this study, through state-of-the-art angle-resolved photoemission spectroscopy, density functional theory, and dynamical mean-field theory calculations, we visualize a fourfold degenerate Dirac nodal line at the boundary of the bulk Brillouin zone in the antiferromagnet YMn2Ge2. We further demonstrate that this gapless, antiferromagnetic Dirac nodal line is enforced by the combination of magnetism, space-time inversion symmetry, and nonsymmorphic lattice symmetry. The corresponding drumhead surface states traverse the whole surface Brillouin zone. YMn2Ge2 thus serves as a platform to exhibit the interplay of multiple degenerate nodal physics and antiferromagnetism. Interestingly, the magnetic nodal line displays a d-orbital dependent renormalization along its trajectory in momentum space, thereby manifesting Hund's coupling. Our findings offer insights into the effect of electronic correlations on magnetic Dirac nodal lines, leading to an antiferromagnetic Hund nodal line.

6.
Nat Commun ; 15(1): 6467, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39085284

RESUMO

A hallmark of unconventional superconductors is a complex electronic phase diagram where intertwined orders of charge-spin-lattice degrees of freedom compete and coexist. While the kagome metals such as CsV3Sb5 also exhibit complex behavior, involving coexisting charge density wave order and superconductivity, much is unclear about the microscopic origin of the superconducting pairing. We study the vortex lattice in the superconducting state of Cs(V0.86Ta0.14)3Sb5, where the Ta-doping suppresses charge order and enhances superconductivity. Using small-angle neutron scattering, a strictly bulk probe, we show that the vortex lattice exhibits a strikingly conventional behavior. This includes a triangular symmetry with a period consistent with 2e-pairing, a field dependent scattering intensity that follows a London model, and a temperature dependence consistent with a uniform superconducting gap. Our results suggest that optimal bulk superconductivity in Cs(V1-xTax)3Sb5 arises from a conventional Bardeen-Cooper-Schrieffer electron-lattice coupling, different from spin fluctuation mediated unconventional copper- and iron-based superconductors.

7.
Nat Mater ; 23(9): 1214-1221, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39009656

RESUMO

A nematic phase breaks the point-group symmetry of the crystal lattice and is known to emerge in correlated materials. Here we report the observation of an intra-unit-cell nematic order and associated Fermi surface deformation in the kagome metal ScV6Sn6. Using scanning tunnelling microscopy and scanning tunnelling spectroscopy, we reveal a stripe-like nematic order breaking the crystal rotational symmetry within the kagome lattice itself. Moreover, we identify a set of Van Hove singularities adhering to the kagome-layer electrons, which appear along one direction of the Brillouin zone and are annihilated along other high-symmetry directions, revealing rotational symmetry breaking. Via detailed spectroscopic maps, we further observe an elliptical deformation of the Fermi surface, which provides direct evidence for an electronically mediated nematic order. Our work not only bridges the gap between electronic nematicity and kagome physics but also sheds light on the potential mechanism for realizing symmetry-broken phases in correlated electron systems.

8.
J Thorac Dis ; 16(5): 3251-3259, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38883687

RESUMO

Background: There is a lack of readily available clinical markers of non-small cell lung cancer (NSCLC) immunotherapy efficacy. Previous studies have found that overexpressed complement component 1q (C1q) promotes macrophage M2 polarization and an immunosuppressive tumor microenvironment. This study aimed to evaluate the association between serum C1q and the efficacy of immune checkpoint inhibitors (ICIs) in patients with advanced NSCLC. Methods: A total of 168 patients with advanced NSCLC who received ICIs in the Renmin Hospital of Wuhan University were included in this study. Serum C1q levels were collected before and 3 weeks after immunotherapy treatment, together with other data on clinical and demographic characteristics. The primary outcome was overall survival (OS) (months from first dose of ICIs to death, censored at date of last follow-up). Secondary outcome was progression-free survival (PFS) [defined as months from first dose of ICIs to clinical or radiographic progression by Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST 1.1) or death, censored at date of last follow-up] and objective response rate (ORR) which was defined as rate of complete response (CR) or partial response (PR) at best response by RECIST 1.1. Results: A total of 168 patients were included in this study, including 127 males (75.60%) and 41 females (24.40%). Thirty-nine patients achieved objective response (2 CR, 37 PR), and 111 patients (66.07%) had stable disease (SD) as best response. The ORR was 23.21% and the disease control rate was 89.28%. The upward trends of serum C1q levels between baseline and post-treatment were strongly associated with the shorter PFS [hazard ratio (HR) =1.554, 95% confidence interval (CI): 1.07-2.10, P=0.01] and OS (HR =1.444, 95% CI: 1.01-1.98, P=0.03). Moreover, taking the median OS 18.9 months as the cut-off of prognosis, receiver operating characteristic (ROC) analysis showed that serum baseline C1q yielded an area under the ROC curve of 0.785 (95% CI: 0.711-0.869). The optimal serum baseline C1q cut-off point to predict immunotherapy prognosis was 216.2 mg/L. Conclusions: These findings suggested that elevated serum C1q after ICIs treatment was related to a worse prognosis in NSCLC. Monitoring the baseline and dynamic data of C1q during hospitalization showed the potential to predict the prognosis of NSCLC patients.

9.
JCI Insight ; 9(14)2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38842940

RESUMO

Loss of ferroptosis contributes to the development of human cancer, and restoration of ferroptosis has been demonstrated as a potential therapeutic strategy in cancer treatment. However, the mechanisms of how ferroptosis escape contributes to ovarian cancer (OV) development are not well elucidated. Here, we show that ferroptosis negative regulation signatures correlated with the tumorigenesis of OV and were associated with poor prognosis, suggesting that restoration of ferroptosis represents a potential therapeutic strategy in OV. High-throughput drug screening with a kinase inhibitor library identified MEK inhibitors as ferroptosis inducers in OV cells. We further demonstrated that MEK inhibitor-resistant OV cells were less vulnerable to trametinib-induced ferroptosis. Mechanistically, mTOR/eIF4E binding protein 1 (4EBP1) signaling promoted solute carrier family 7 member 11 (SLC7A11) protein synthesis, leading to ferroptosis inhibition in MEK inhibitor-resistant cells. Dual inhibition of MEK and mTOR/4EBP1 signaling restrained the protein synthesis of SLC7A11 via suppression of the mTOR/4EBP1 axis to reactivate ferroptosis in resistant cells. Together, these findings provide a promising therapeutic option for OV treatment through ferroptosis restoration by the combined inhibition of MEK and mTOR/4EBP1 pathways.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Sistema y+ de Transporte de Aminoácidos , Ferroptose , Neoplasias Ovarianas , Inibidores de Proteínas Quinases , Serina-Treonina Quinases TOR , Ferroptose/efeitos dos fármacos , Humanos , Feminino , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/genética , Linhagem Celular Tumoral , Sistema y+ de Transporte de Aminoácidos/metabolismo , Sistema y+ de Transporte de Aminoácidos/genética , Sistema y+ de Transporte de Aminoácidos/antagonistas & inibidores , Animais , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Camundongos , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Serina-Treonina Quinases TOR/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Transdução de Sinais/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Piridonas/farmacologia , Piridonas/uso terapêutico , Pirimidinonas/farmacologia , Pirimidinonas/uso terapêutico
10.
Front Oncol ; 14: 1387388, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38715777

RESUMO

The v-raf murine sarcoma viral oncogenic homolog B1 (BRAF) V600E is a rare mutation that functions as an oncogenic driver in patients with non-small cell lung cancer (NSCLC) leading to the overactivation of the RAS-RAF-MEK-ERK (MAPK) pathway and the subsequent uncontrolled cell proliferation. Understanding the mechanism behind BRAF mutation, its inhibition, and relationship to the upstream and downstream effector is essential for advancing treatment strategies for NSCLC patients with the BRAF V600E mutation. Next-generation sequencing studies have identified the presence of breast cancer susceptibility gene 1/2 (BRCA1/2) mutations in NSCLC patients, which are pathogenic variants associated with breast, ovarian, and prostate cancers. Although poly ADP-ribose polymerase (PARP) inhibitors are currently an approved treatment option for malignant tumors linked to BRCA1/2 pathogenic variants, the therapeutic potential of PARP inhibitors in NSCLC remains unclear. The development of genetic testing provides a platform for investigating the pathophysiological mechanisms of genetic mutations above. Here, we report a novel case of a middle-aged non-smoking female diagnosed with BRAF V600E and BRCA2 germline mutated lung adenocarcinoma, who had previously undergone a diverse array of cancer-targeted therapies, including PARP inhibitor, before the identification of the BRAF V600E mutation. Following this, a combination of dabrafenib and trametinib was administered and induced a rapid and positive response within two months. Our case not only highlights the importance of dynamic and repetitive genetic testing in managing patients, but contributes to the growing body of clinical evidence supporting the efficacy of BRAF/MEK co-inhibition in patients harboring a BRAF V600E mutation and provokes thinking for further research into the impact of PARP inhibitors in BRCA1/2-mutated NSCLC.

11.
Sci Rep ; 14(1): 9580, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38671053

RESUMO

Kagome superconductors AV3Sb5 (A = K, Rb, and Cs) have attracted enormous interest due to the coexistence of charge density wave (CDW) order, unconventional superconductivity (SC) and anomalous Hall effect (AHE). In this paper, we reported an intensive investigation on Cs(V1-xTax)3Sb5 single crystals with systematic Ta doping. Ta was confirmed to be doped into V-site in the Kagome layer from both single crystal X-ray diffraction structural refinement and scanning transmission electron microscopy observation. The highest Ta doping level was found to be about 16%, which is more than twice as much as 7% in Nb-doped CsV3Sb5. With the increase of Ta doping, CDW order was gradually suppressed and finally vanished when the doping level reached to more than 8%. Meanwhile, superconductivity was enhanced with a maximum critical temperature (Tc) of 5.3 K, which is the highest Tc in the bulk crystal of this Kagome system at ambient pressure so far. The µ0Hc2(T) behavior demonstrates that the system is still a two-band superconductor after Ta doping. Based on the electrical transport measurement, a phase diagram was set up to exhibit the evolution of CDW and SC in the Cs(V1-xTax)3Sb5 system. These findings pave a new way to search for new superconductors with higher Tc in the AV3Sb5 family and establish a new platform for tuning and controlling the multiple orders and superconducting states.

12.
Nature ; 628(8008): 527-533, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38600389

RESUMO

Topology1-3 and interactions are foundational concepts in the modern understanding of quantum matter. Their nexus yields three important research directions: (1) the competition between distinct interactions, as in several intertwined phases, (2) the interplay between interactions and topology that drives the phenomena in twisted layered materials and topological magnets, and (3) the coalescence of several topological orders to generate distinct novel phases. The first two examples have grown into major areas of research, although the last example remains mostly unexplored, mainly because of the lack of a material platform for experimental studies. Here, using tunnelling microscopy, photoemission spectroscopy and a theoretical analysis, we unveil a 'hybrid' topological phase of matter in the simple elemental-solid arsenic. Through a unique bulk-surface-edge correspondence, we uncover that arsenic features a conjoined strong and higher-order topology that stabilizes a hybrid topological phase. Although momentum-space spectroscopy measurements show signs of topological surface states, real-space microscopy measurements unravel a unique geometry of topologically induced step-edge conduction channels revealed on various natural nanostructures on the surface. Using theoretical models, we show that the existence of gapless step-edge states in arsenic relies on the simultaneous presence of both a non-trivial strong Z2 invariant and a non-trivial higher-order topological invariant, which provide experimental evidence for hybrid topology. Our study highlights pathways for exploring the interplay of different band topologies and harnessing the associated topological conduction channels in engineered quantum or nano-devices.

15.
Rapid Commun Mass Spectrom ; 38(6): e9693, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38356085

RESUMO

RATIONALE: The volatile organic compounds (VOCs) of Lonicerae Japonicae flos (LJF) and Lonicera flos (LF) play a pivotal role in determining their sensory characteristics, medicinal properties, and subsequent impact on market pricing and consumer preferences. However, the differences and specificity of these VOCs remain obscure. Hence, it is crucial to conduct a comprehensive characterization of the VOCs in LJF and LF and pinpoint their potential differential VOCs. METHODS: In this study, headspace gas chromatography-ion mobility spectrometry (HS-GC/IMS) and headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC/MS) were employed to comprehensively investigate the compositional characteristics and distinctions in VOCs between LJF and LF. Multivariate statistical analysis was used to identify candidate differential VOCs of LJF and LF samples. RESULTS: A total of 54 and 88 VOCs were identified using HS-GC/IMS and HS-SPME-GC/MS analysis, respectively. Primary VOCs detected in LJF include leaf alcohol, (E)-2-hexen-1-ol dimer, 2-octyn-1-ol, and (E)-3-hexen-1-ol. Key VOCs prevalent in LF encompass farnesol, heptanoic acid, octanoic acid, and valeric acid. Multivariate statistical analysis indicates that compounds such as phenethyl alcohol and leaf alcohol were selected as potential VOCs for distinguishing between LJF and LF. CONCLUSION: This research conducted a comprehensive analysis of the fundamental volatile components in both LJF and LF. It subsequently elucidated the distinctions and specificities within their respective VOC profiles. And this study enables differentiation between LJF and LF through the analysis of VOCs, offering valuable insights for enhancing the quality control of both LJF and LF.


Assuntos
Lonicera , Extratos Vegetais , Compostos Orgânicos Voláteis , Cromatografia Gasosa-Espectrometria de Massas/métodos , Compostos Orgânicos Voláteis/análise , Microextração em Fase Sólida/métodos , Espectrometria de Mobilidade Iônica , Etanol
16.
Molecules ; 29(3)2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38338347

RESUMO

The flower buds of three Panax species (PGF: P. ginseng; PQF: P. quinquefolius; PNF: P. notoginseng) widely consumed as health tea are easily confused in market circulation. We aimed to develop a green, fast, and easy analysis strategy to distinguish PGF, PQF, and PNF. In this work, fast gas chromatography electronic nose (fast GC e-nose), headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS), and headspace solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) were utilized to comprehensively analyze the volatile organic components (VOCs) of three flowers. Meanwhile, a principal component analysis (PCA) and heatmap were applied to distinguish the VOCs identified in PGF, PQF, and PNF. A random forest (RF) analysis was used to screen key factors affecting the discrimination. As a result, 39, 68, and 78 VOCs were identified in three flowers using fast GC e-nose, HS-GC-IMS, and HS-SPME-GC-MS. Nine VOCs were selected as potential chemical markers based on a model of RF for distinguishing these three species. Conclusively, a complete VOC analysis strategy was created to provide a methodological reference for the rapid, simple, and environmentally friendly detection and identification of food products (tea, oil, honey, etc.) and herbs with flavor characteristics and to provide a basis for further specification of their quality and base sources.


Assuntos
Panax , Compostos Orgânicos Voláteis , Cromatografia Gasosa-Espectrometria de Massas/métodos , Nariz Eletrônico , Microextração em Fase Sólida/métodos , Panax/química , Espectrometria de Mobilidade Iônica , Compostos Orgânicos Voláteis/análise , Flores/química , Chá
17.
Oncogene ; 43(15): 1149-1159, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38396292

RESUMO

O-linked-ß-N-acetylglucosamine (O-GlcNAc) modification (O-GlcNAcylation) and ubiquitination are critical posttranslational modifications that regulate tumor development and progression. The continuous progression of the cell cycle is the fundamental cause of tumor proliferation. S-phase kinase-associated protein 2 (SKP2), an important E3 ubiquitin ligase, assumes a pivotal function in the regulation of the cell cycle. However, it is still unclear whether SKP2 is an effector of O-GlcNAcylation that affects tumor progression. In this study, we found that SKP2 interacted with O-GlcNAc transferase (OGT) and was highly O-GlcNAcylated in hepatocellular carcinoma (HCC). Mechanistically, the O-GlcNAcylation at Ser34 stabilized SKP2 by reducing its ubiquitination and degradation mediated by APC-CDH1. Moreover, the O-GlcNAcylation of SKP2 enhanced its binding ability with SKP1, thereby enhancing its ubiquitin ligase function. Consequently, SKP2 facilitated the transition from the G1-S phase of the cell cycle by promoting the ubiquitin degradation of cell cycle-dependent kinase inhibitors p27 and p21. Additionally, targeting the O-GlcNAcylation of SKP2 significantly suppressed the proliferation of HCC. Altogether, our findings reveal that O-GlcNAcylation, a novel posttranslational modification of SKP2, plays a crucial role in promoting HCC proliferation, and targeting the O-GlcNAcylation of SKP2 may become a new therapeutic strategy to impede the progression of HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Proteínas Quinases Associadas a Fase S , Humanos , Carcinoma Hepatocelular/patologia , Divisão Celular , Neoplasias Hepáticas/patologia , Proteínas Quinases Associadas a Fase S/genética , Proteínas Quinases Associadas a Fase S/metabolismo , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
18.
Nat Commun ; 15(1): 1658, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38395887

RESUMO

Charge density wave (CDW) orders in vanadium-based kagome metals have recently received tremendous attention, yet their origin remains a topic of debate. The discovery of ScV6Sn6, a bilayer kagome metal featuring an intriguing [Formula: see text] CDW order, offers a novel platform to explore the underlying mechanism behind the unconventional CDW. Here, we combine high-resolution angle-resolved photoemission spectroscopy, Raman scattering and density functional theory to investigate the electronic structure and phonon modes of ScV6Sn6. We identify topologically nontrivial surface states and multiple van Hove singularities (VHSs) in the vicinity of the Fermi level, with one VHS aligning with the in-plane component of the CDW vector near the [Formula: see text] point. Additionally, Raman measurements indicate a strong electron-phonon coupling, as evidenced by a two-phonon mode and new emergent modes. Our findings highlight the fundamental role of lattice degrees of freedom in promoting the CDW in ScV6Sn6.

19.
Biomater Sci ; 12(5): 1197-1210, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38240497

RESUMO

Genome editing mediated by CRISPR/Cas9 is an attractive weapon for cancer therapy. However, in vivo delivery of CRISPR/Cas9 components to achieve therapeutic efficiency is still challenging. Herein, a quaternary ammonium-functionalized poly(L-lysine) and a cholesterol-modified PEG (QNP) were self-assembled with a negatively charged CRISPR Cas9/sgRNA ribonucleoprotein (RNP) to form a ternary complex (QNP/RNP). Such a delivery system of QNP exhibited multiplex genome editing capabilities in vitro (e.g., the GFP gene and the PLK1 gene). In addition, QNP/RNPPLK1 containing PLK1 sgRNA led to 30.99% of genome editing efficiency in MCF-7 cells with negligible cytotoxicity of the carrier. QNP/RNPPLK1, which was capable of simultaneously inhibiting cell proliferation, mediating cell cycle arrest and downregulating expression of PLK1, held great in vitro therapeutic efficiency. Moreover, QNP/RNPPLK1 exhibited outstanding accumulation in tumors and high biocompatibility in vivo. In an MCF-7 xenograft animal model, QNP/RNPPLK1 showed excellent anti-tumor efficacy and achieved 17.75% indels ratio. This work showcases the successful delivery of CRISPR Cas9/sgRNA RNP with enhanced genome editing efficiency and provides a potential on-demand strategy for cancer therapy.


Assuntos
Compostos de Amônio , Neoplasias , Animais , Humanos , Sistemas CRISPR-Cas/genética , RNA Guia de Sistemas CRISPR-Cas , Edição de Genes , Ribonucleoproteínas/genética , Neoplasias/tratamento farmacológico , Neoplasias/genética
20.
J Pharm Biomed Anal ; 239: 115910, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38101240

RESUMO

Xiaoyao Wan (XYW) is a prescription medicine of traditional Chinese medicine (TCM) with the effects of "soothing the liver and relieving depression," and "strengthening spleen and nourishing blood". XYW has been widely concerned in the treatment of depression and has become one of the commonly used classic formulas in clinical practice. However, the pharmacodynamic substance basis and the quality control studies of XYW are hitherto quite limited. Here, we aim to fully utilize an advanced ultra - performance liquid chromatography-quadrupole - Orbitrap mass spectrometry (UPLC-Q-Orbitrap-MS), headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) and headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) technique to deep characterization of the pharmacological substance basis and quantitatively evaluate the quality of XYW. Firstly, 299 compounds were identified or tentatively characterized, including 198 non-volatile organic compounds (n-VOCs) and 101 volatile organic compounds (VOCs). Secondly, principal component analysis (PCA) and hierarchical cluster analysis (HCA) was used to analyze quality differences in XYW at different manufacturers. Thirdly, a parallel reaction monitoring (PRM) method was established and validated to quantify the fourteen major effective substances in different manufacturers of XYW, which were chosen as the benchmarked substances to evaluate the quality of XYW. In conclusion, this study shows that the strategy provides a useful method for quality control of TCM and offers a practical workflow for exploring the quality consistency of TCM.


Assuntos
Medicamentos de Ervas Chinesas , Compostos Orgânicos Voláteis , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão , Compostos Orgânicos Voláteis/análise
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