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1.
Nanoscale ; 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39405055

RESUMO

Graphene plasmons exhibit significant potential across diverse fields, including optoelectronics, metamaterials, and biosensing. However, the exposure of all surface atoms in graphene makes it susceptible to surrounding interference, including losses stemming from charged impurity scattering, the dielectric environment, and the substrate roughness. Thus, designing a dielectric environment with a long lifetime and tunability is essential. In this study, we created a van der Waals (vdW) heterostructure with graphene nanoribbons and mica nano-films. Through Fourier-transform infrared spectroscopy, we identified hybrid modes resulting from the interaction between graphene plasmons and mica phonons. By doping and manipulating the structure of graphene, we achieved control over the phonon-plasmon ratio, thereby influencing the characteristics of these modes. Phonon-dominated modes exhibited stable resonant frequencies, whereas plasmon-dominated modes demonstrated continuous tuning from 1140 to 1360 cm-1 in resonance frequency, accompanied by an increase in extinction intensity from 0.1% to 1.2%. Multiple phonon couplings limited frequency modulation, yielding stable resonances unaffected by the gate voltage. Mica substrates offer atomic level flatness, long phonon lifetimes, and dielectric functionality, enabling hybrid modes with high confinement, extended lifetimes (up to 1.9 picoseconds), and a broad frequency range (from 750 cm-1 to 1450 cm-1). These properties make our graphene and mica heterostructure promising for applications in chemical sensing and integrated photonic devices.

2.
Elife ; 132024 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-39412391

RESUMO

Mitotic anaphase onset is a key cellular process tightly regulated by multiple kinases. The involvement of mitogen-activated protein kinases (MAPKs) in this process has been established in Xenopus egg extracts. However, the detailed regulatory cascade remains elusive, and it is also unknown whether the MAPK-dependent mitotic regulation is evolutionarily conserved in the single-cell eukaryotic organisms such as fission yeast (Schizosaccharomyces pombe). Here, we show that two MAPKs in S. pombe indeed act in concert to restrain anaphase-promoting complex/cyclosome (APC/C) activity upon activation of the spindle assembly checkpoint (SAC). One MAPK, Pmk1, binds to and phosphorylates Slp1Cdc20, the co-activator of APC/C. Phosphorylation of Slp1Cdc20 by Pmk1, but not by Cdk1, promotes its subsequent ubiquitylation and degradation. Intriguingly, Pmk1-mediated phosphorylation event is also required to sustain SAC under environmental stress. Thus, our study establishes a new underlying molecular mechanism of negative regulation of APC/C by MAPK upon stress stimuli, and provides a previously unappreciated framework for regulation of anaphase entry in eukaryotic cells.


Assuntos
Ciclossomo-Complexo Promotor de Anáfase , Proteínas Cdc20 , Proteínas Quinases Ativadas por Mitógeno , Schizosaccharomyces , Ciclossomo-Complexo Promotor de Anáfase/metabolismo , Schizosaccharomyces/metabolismo , Proteínas Cdc20/metabolismo , Proteínas Cdc20/genética , Fosforilação , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/genética , Estresse Fisiológico , Proteínas de Schizosaccharomyces pombe/metabolismo , Proteínas de Schizosaccharomyces pombe/genética
3.
Nat Commun ; 15(1): 7813, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39242560

RESUMO

Humans can be exposed to multiple pollutants in the air and surface water. These environments are non-static, trans-boundary and correlated, creating a complex network, and significant challenges for research on environmental hazards, especially in real-world cancer research. This article reports on a large study (377 million people in 30 provinces of China) that evaluated the combined impact of air and surface water pollution on cancer. We formulate a spatial evaluation system and a common grading scale for co-pollution measurement, and validate assumptions that air and surface water environments are spatially connected and that cancers of different types tend to cluster in areas where these environments are poorer. We observe "dose-response" relationships in both the number of affected cancer types and the cancer incidence with an increase in degree of co-pollution. We estimate that 62,847 (7.4%) new cases of cancer registered in China in 2016 were attributable to air and surface water pollution, and the majority (69.7%) of these excess cases occurred in areas with the highest level of co-pollution. The findings clearly show that the environment cannot be considered as a set of separate entities. They also support the development of policies for cooperative environmental governance and disease prevention.


Assuntos
Poluição do Ar , Exposição Ambiental , Neoplasias , China/epidemiologia , Humanos , Neoplasias/epidemiologia , Neoplasias/etiologia , Neoplasias/induzido quimicamente , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Exposição Ambiental/efeitos adversos , Poluição da Água/efeitos adversos , Incidência , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/efeitos adversos
4.
Biomed Chromatogr ; 38(10): e5987, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39126351

RESUMO

The traditional formulation Hanchuan zupa granules (HCZPs) have been widely used for controlling coronavirus disease 2019 (COVID-19). However, its active components remain unknown. Here, HCZP components targeting the spike receptor-binding domain (S-RBD) of SARS-CoV-2 were investigated using a surface plasmon resonance (SPR) biosensor-based active ingredient recognition system (SPR-AIRS). Recombinant S-RBD proteins were immobilized on the SPR chip by amine coupling for the prescreening of nine HCZP medicinal herbs. Ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) identified gallic acid (GA) and methyl gallate (MG) from Rosa rugosa as S-RBD ligands, with KD values of 2.69 and 0.95 µM, respectively, as shown by SPR. Molecular dynamics indicated that GA formed hydrogen bonds with G496, N501, and Y505 of S-RBD, and MG with G496 and Y505, inhibiting S-RBD binding to angiotensin-converting enzyme 2 (ACE2). SPR-based competition analysis verified that both compounds blocked S-RBD and ACE2 binding, and SPR demonstrated that GA and MG bound to ACE2 (KD = 5.10 and 4.05 µM, respectively), suggesting that they blocked the receptor and neutralized SARS-CoV-2. Infection with SARS-CoV-2 pseudovirus showed that GA and MG suppressed viral entry into 293T-ACE2 cells. These S-RBD inhibitors have potential for drug design, while the findings provide a reference on HCZP composition and its use for treating COVID-19.


Assuntos
Ácido Gálico , Rosa , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Ressonância de Plasmônio de Superfície , Glicoproteína da Espícula de Coronavírus/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/antagonistas & inibidores , SARS-CoV-2/efeitos dos fármacos , Ressonância de Plasmônio de Superfície/métodos , Ácido Gálico/farmacologia , Ácido Gálico/química , Ácido Gálico/análogos & derivados , Humanos , Rosa/química , Antivirais/farmacologia , Antivirais/química , Antivirais/análise , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/química , Enzima de Conversão de Angiotensina 2/metabolismo , Enzima de Conversão de Angiotensina 2/química , Espectrometria de Massas em Tandem/métodos , Técnicas Biossensoriais/métodos , Internalização do Vírus/efeitos dos fármacos , Tratamento Farmacológico da COVID-19 , Cromatografia Líquida de Alta Pressão/métodos , Ligação Proteica , Simulação de Dinâmica Molecular , COVID-19/virologia
5.
IUBMB Life ; 76(10): 832-844, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39012196

RESUMO

Osteoporosis (OP) is a systemic metabolic bone disease resulting in reduced bone strength and increased susceptibility to fractures, making it a significant public health and economic problem worldwide. The clinical use of anti-osteoporosis agents is limited because of their serious side effects or the high cost of long-term use. The Xianlinggubao (XLGB) formula is an effective traditional Chinese herbal medicine commonly used in orthopedics to treat osteoporosis; however, its mechanism of action remains unclear. In this study, we screened 40 small RNAs derived from XLGB capsules and found that XLGB28-sRNA targeting TNFSF11 exerted a significant anti-osteoporosis effect in vitro and in vivo by simultaneously promoting osteogenesis and inhibiting osteoclastogenesis. Oral administration of bencaosome [16:0 Lyso PA+XLGB28-sRNA] effectively improved bone mineral density and reduced the damage to the bone microstructure in mice. These results suggest that XLGB28-sRNA may be a novel oligonucleotide drug that promotes osteogenesis and inhibits osteoclastogenesis in mice.


Assuntos
Densidade Óssea , Medicamentos de Ervas Chinesas , Osteoclastos , Osteogênese , Osteoporose , Animais , Osteogênese/efeitos dos fármacos , Osteoporose/tratamento farmacológico , Osteoporose/patologia , Camundongos , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Osteoclastos/patologia , Densidade Óssea/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Feminino , Camundongos Endogâmicos C57BL , Diferenciação Celular/efeitos dos fármacos , Lipossomos/química , Células RAW 264.7 , Modelos Animais de Doenças , Ligante RANK
6.
IUBMB Life ; 76(11): 937-950, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39051847

RESUMO

In 2020, the number of deaths caused by lung cancer worldwide reached 1,796,144, making it the leading cause of cancer-related deaths. Cyclooxygenase-2/prostaglandin endoperoxide synthase 2 (COX-2/PTGS2) is overexpressed in lung cancer, which promotes tumor proliferation, invasion, angiogenesis, and resistance to apoptosis. Here, we report that the oligonucleotide drug HQi-sRNA-2 from Traditional Chinese Medicine Huangqin targeting COX-2/PTGS2 significantly inhibited proliferation, migration, and invasion and induced apoptosis in the human lung cancer cell line NCI-H460. Oral delivery of HQi-sRNA-2 bencaosomes prolonged survival, reduced tumor burden, and maintained weight in a spontaneous mouse lung cancer model. Compared with paclitaxel, HQi-sRNA-2 may be less toxic and have approximately equal efficacy in reducing tumor burden. Our previous studies reported that herbal small RNAs (sRNAs) are functional medical components. Our data suggest that sphingosine (d18:1)-HQi-sRNA-2 bencaosomes, targeting COX-2/PTGS2 and downregulating the PI3K and AKT signaling pathways, may provide novel therapeutics for lung cancer.


Assuntos
Apoptose , Proliferação de Células , Ciclo-Oxigenase 2 , Medicamentos de Ervas Chinesas , Neoplasias Pulmonares , Animais , Ciclo-Oxigenase 2/metabolismo , Ciclo-Oxigenase 2/genética , Camundongos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Humanos , Proliferação de Células/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Movimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Transdução de Sinais/efeitos dos fármacos , Modelos Animais de Doenças , Ensaios Antitumorais Modelo de Xenoenxerto , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos
7.
Phys Rev Lett ; 132(25): 256503, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38996236

RESUMO

The recently discovered superconductivity with critical temperature T_{c} up to 80 K in the double-layer Nickelate La_{3}Ni_{2}O_{7-δ} under pressure has drawn great attention. Here, we report the positive muon spin relaxation (µ^{+}SR) study of polycrystalline La_{3}Ni_{2}O_{6.92} under ambient pressure. Zero-field µ^{+}SR experiments reveal the existence of magnetic order in La_{3}Ni_{2}O_{6.92} with T_{N}=154 K. The weak transverse field µ^{+}SR measurements reveal the bulk nature of magnetism. In addition, a small quantity of oxygen deficiencies can greatly broaden the internal magnetic field distribution sensed by muons.

8.
IUBMB Life ; 76(11): 960-971, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38923653

RESUMO

To date, SARS-CoV-2 has caused millions of deaths, but the choice of treatment is limited. We previously established a platform for identifying Food and Drug Administration (FDA)-approved repurposed drugs for avian influenza A virus infections that could be used for coronavirus disease 2019 (COVID-19) treatment. In this study, we analyzed blood samples from two cohorts of 63 COVID-19 patients, including 19 patients with severe disease. Among the 39 FDA-approved drugs we identified for COVID-19 therapy in both cohorts, 23 drugs were confirmed by literature mining data, including 14 drugs already under COVID-19 clinical trials and 9 drugs reported for COVID-19 treatments, suggesting the remaining 16 FDA-approved drugs may be candidates for COVID-19 therapy. Additionally, we previously reported that herbal small RNAs (sRNAs) could be effective components in traditional Chinese medicine (TCM) for treating COVID-19. Based on the abundance of sRNAs, we screened the 245 TCMs in the Bencao (herbal) sRNA Atlas that we had previously established, and we found that the top 12 TCMs for COVID-19 treatment was consistent across both cohorts. We validated the efficiency of the top 30 sRNAs from each of the top 3 TCMs for COVID-19 treatment in poly(I:C)-stimulated human non-small cell lung cancer cells (A549 cells). In conclusion, our study recommends potential COVID-19 remedies using FDA-approved repurposed drugs and herbal sRNAs from TCMs.


Assuntos
Antivirais , Tratamento Farmacológico da COVID-19 , Reposicionamento de Medicamentos , Medicamentos de Ervas Chinesas , SARS-CoV-2 , Humanos , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/genética , Antivirais/farmacologia , Antivirais/uso terapêutico , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , COVID-19/virologia , Medicina Tradicional Chinesa , Masculino , Feminino , Pessoa de Meia-Idade , RNA de Plantas/genética
9.
IUBMB Life ; 76(11): 951-959, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38935610

RESUMO

Type 2 diabetes mellitus is a prevalent metabolic disease, posing a considerable threat to public health. Oligonucleotide drugs have proven to be a promising field of therapy for the diseases. In this study, we reported that a herbal small RNA (sRNA), JGL-sRNA-h7 (B34735529, F1439.L002444.A11), could exhibit potent hypoglycemic effects by targeting glucose-6-phosphatase. Oral administration of sphingosine (d18:1)-JGL-sRNA-h7 bencaosomes ameliorated hyperglycemia and diabetic kidney injury better than metformin in db/db mice. Furthermore, glucose tolerance was also improved in sphingosine (d18:1)-JGL-sRNA-h7 bencaosomes-treated beagle dogs. Our study indicates that JGL-sRNA-h7 could be a promising hypoglycemic oligonucleotide drug.


Assuntos
Hiperglicemia , Hipoglicemiantes , Animais , Cães , Hiperglicemia/tratamento farmacológico , Camundongos , Administração Oral , Hipoglicemiantes/farmacologia , Hipoglicemiantes/administração & dosagem , Masculino , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/patologia , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Oligonucleotídeos/administração & dosagem , Camundongos Endogâmicos C57BL
10.
Dalton Trans ; 53(20): 8732-8739, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38712507

RESUMO

Interfacial engineering emerges as a potent strategy for regulating the catalytic reactivity of metal phosphides. Developing a facile and cost-effective method to construct bifunctional metal phosphides for highly efficient electrochemical overall water splitting remains an essential and challenging issue. Here, a multiphase transition metal phosphide is constructed through the direct phosphorization of a Ni-Co metal-organic framework grown on nickel foam (Ni-Co-MOF/NF), which is prepared by utilizing nickel foam as conductive substrate and nickel source. The resulting transition metal phosphide manifests a pillar-layered morphology, wherein CoP, Ni2P, and Ni5P4 nanoparticles are embedded within each carbon sheet and these carbon sheets assemble into a pillar-shaped structure on the nickel foam (Ni2P-Ni5P4-CoP-C/NF). The heterogeneous Ni2P-Ni5P4-CoP-C/NF with multiple interfaces serves as a highly efficient bifunctional electrocatalyst with overpotentials of -100 mV and 293 mV in the hydrogen evolution reaction and oxygen evolution reaction, respectively, at 50 mA cm-2 in alkaline media. This superior catalytic performance should mainly be ascribed to its enriched active centers and multiphase synergy. When directly applied for alkaline overall water splitting, the Ni2P-Ni5P4-CoP-C/NF couple demonstrates satisfactory activity (1.55 V @10 mA cm-2) along with sustained durability over 18 hours. This method brings fresh enlightenment to the economical and controllable preparation of multi-metal phosphides for energy conversion.

11.
Chin Herb Med ; 16(1): 3-12, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38375050

RESUMO

To promote the development of extracellular vesicles of herbal medicine especially the establishment of standardization, led by the National Expert Committee on Research and Application of Chinese Herbal Vesicles, research experts in the field of herbal medicine and extracellular vesicles were invited nationwide with the support of the Expert Committee on Research and Application of Chinese Herbal Vesicles, Professional Committee on Extracellular Vesicle Research and Application, Chinese Society of Research Hospitals and the Guangdong Engineering Research Center of Chinese Herbal Vesicles. Based on the collation of relevant literature, we have adopted the Delphi method, the consensus meeting method combined with the nominal group method to form a discussion draft of "Consensus statement on research and application of Chinese herbal medicine derived extracellular vesicles-like particles (2023)". The first draft was discussed in online and offline meetings on October 12, 14, November 2, 2022 and April and May 2023 on the current status of research, nomenclature, isolation methods, quality standards and research applications of extracellular vesicles of Chinese herbal medicines, and 13 consensus opinions were finally formed. At the Third Academic Conference on Research and Application of Chinese Herbal Vesicles, held on May 26, 2023, Kewei Zhao, convenor of the consensus, presented and read the consensus to the experts of the Expert Committee on Research and Application of Chinese Herbal Vesicles. The consensus highlights the characteristics and advantages of Chinese medicine, inherits the essence, and keeps the righteousness and innovation, aiming to provide a reference for colleagues engaged in research and application of Chinese herbal vesicles at home and abroad, decode the mystery behind Chinese herbal vesicles together, establish a safe, effective and controllable accurate Chinese herbal vesicle prevention and treatment system, and build a bridge for Chinese medicine to the world.

12.
J Antibiot (Tokyo) ; 77(4): 201-205, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38273126

RESUMO

Assisted by OSMAC strategy, one new p-terphenyl and two new α­pyrone derivates, namely nocarterphenyl I (1) and nocardiopyrone D-E (2-3), were obtained and characterized from the marine sediment-derived actinomycete Nocardiopsis sp. HDN154086. The structures of these compounds were determined on the basis of MS, NMR spectroscopic data and single-crystal X-ray diffraction. Compound 1 with a rare 2,2'-bithiazole structure among natural products showed promising activity against five bacteria with MIC values ranging from 0.8 to 1.6 µM and 3 exhibited notable antibacterial activity against MRSA compared the positive control ciprofloxacin.


Assuntos
Actinobacteria , Compostos de Terfenil , Actinobacteria/química , Nocardiopsis , Pironas/química , Estrutura Molecular , Antibacterianos/química , Compostos de Terfenil/química
13.
Respir Res ; 24(1): 306, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38057804

RESUMO

BACKGROUND: Particulate matter (PM) air pollution poses a significant risk to respiratory health and is especially linked with various infectious respiratory diseases such as influenza. Our previous studies have shown that H5N1 virus infection could induce alveolar epithelial A549 cell death by enhancing lysosomal dysfunction. This study aims to investigate the mechanisms underlying the effects of PM on influenza virus infections, with a particular focus on lysosomal dysfunction. RESULTS: Here, we showed that PM nanoparticles such as silica and alumina could induce A549 cell death and lysosomal dysfunction, and degradation of lysosomal-associated membrane proteins (LAMPs), which are the most abundant lysosomal membrane proteins. The knockdown of LAMPs with siRNA facilitated cellular entry of both H1N1 and H5N1 influenza viruses. Furthermore, we demonstrated that silica and alumina synergistically increased alveolar epithelial cell death induced by H1N1 and H5N1 influenza viruses by enhancing lysosomal dysfunction via LAMP degradation and promoting viral entry. In vivo, lung injury in the H5N1 virus infection-induced model was exacerbated by pre-exposure to silica, resulting in an increase in the wet/dry ratio and histopathological score. CONCLUSIONS: Our findings reveal the mechanism underlying the synergistic effect of nanoparticles in the early stage of the influenza virus life cycle and may explain the increased number of respiratory patients during periods of air pollution.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Virus da Influenza A Subtipo H5N1 , Vírus da Influenza A , Influenza Humana , Lesão Pulmonar , Humanos , Animais , Camundongos , Lesão Pulmonar/induzido quimicamente , Lisossomos , Óxido de Alumínio , Dióxido de Silício
14.
Angew Chem Int Ed Engl ; 62(50): e202315136, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-37902429

RESUMO

The helical twisting tendency of liquid crystals (LCs) is generally governed by the inherent configuration of the chiral emitter. Here, we introduce the multistage inversion of supramolecular chirality as well as circularly polarized luminescence (CPL) by manipulating the ratio of single enantiomeric emitters (R-PCP) to LC monomers (5CB). Increasing the content of R-PCP from 1 wt % to 3 wt % inverted the helix of LCs from left-handed to right-handed, accompanying a CPL sign changed from positive to negative. The biaxiality of chiral emitters, as well as the steric effect of chiral-chiral and chiral-achiral interaction, were identified as the reasons for helical sense inversion. Due to the strong helical twisting power, 4 wt % R-PCP drove the photonic band gap (PBG) of chiral LCs to match up with their emission range, leading to an inversion of the CPL again with a high dissymmetry factor (≈1.2). Directly adjusting the PBG using chiral emitters is seldom achieved in cholesteric LCs. On this basis, an achiral sensitizer PtTPBP was assembled into the helical superstructure. The generation of triplet-triplet annihilation-induced upconverted CPL from R-PCP and the downshifting CPL from PtTPBP with opposite rotation was achieved in a single chiral LC system by tuning the position of the PBG.

15.
Nanoscale ; 15(38): 15450-15471, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37721398

RESUMO

Against the backdrop of advocacy for green and low-carbon development, electrochromism has attracted academic and industrial attention as an intelligent and energy-saving applied technology due to its optical switching behavior and its special principles of operation. Inorganic electrochromic materials, represented by transition metal oxides, are considered candidates for the next generation of large-scale electrochromic applied technologies due to their excellent stability. However, the limited color diversity and low color purity of these materials greatly restrict their development. Starting from the multicolor properties of inorganic electrochromic materials, this review systematically elaborates on recent progress in the aspects of the intrinsic multicolor of electrochromic materials, and structural multicolor based on the interaction between light and microstructure. Finally, the challenges and opportunities of inorganic electrochromic technology in the field of multicolor are discussed.

16.
Entropy (Basel) ; 25(9)2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37761652

RESUMO

Recent research has shown that visual-text pretrained models perform well in traditional vision tasks. CLIP, as the most influential work, has garnered significant attention from researchers. Thanks to its excellent visual representation capabilities, many recent studies have used CLIP for pixel-level tasks. We explore the potential abilities of CLIP in the field of few-shot segmentation. The current mainstream approach is to utilize support and query features to generate class prototypes and then use the prototype features to match image features. We propose a new method that utilizes CLIP to extract text features for a specific class. These text features are then used as training samples to participate in the model's training process. The addition of text features enables model to extract features that contain richer semantic information, thus making it easier to capture potential class information. To better match the query image features, we also propose a new prototype generation method that incorporates multi-modal fusion features of text and images in the prototype generation process. Adaptive query prototypes were generated by combining foreground and background information from the images with the multi-modal support prototype, thereby allowing for a better matching of image features and improved segmentation accuracy. We provide a new perspective to the task of few-shot segmentation in multi-modal scenarios. Experiments demonstrate that our proposed method achieves excellent results on two common datasets, PASCAL-5i and COCO-20i.

17.
Innovation (Camb) ; 4(5): 100459, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37560333

RESUMO

The search of quantum spin liquid (QSL), an exotic magnetic state with strongly fluctuating and highly entangled spins down to zero temperature, is a main theme in current condensed matter physics. However, there is no smoking gun evidence for deconfined spinons in any QSL candidate so far. The disorders and competing exchange interactions may prevent the formation of an ideal QSL state on frustrated spin lattices. Here we report comprehensive and systematic measurements of the magnetic susceptibility, ultralow-temperature specific heat, muon spin relaxation (µSR), nuclear magnetic resonance (NMR), and thermal conductivity for NaYbSe2 single crystals, in which Yb3+ ions with effective spin-1/2 form a perfect triangular lattice. All these complementary techniques find no evidence of long-range magnetic order down to their respective base temperatures. Instead, specific heat, µSR, and NMR measurements suggest the coexistence of quasi-static and dynamic spins in NaYbSe2. The scattering from these quasi-static spins may cause the absence of magnetic thermal conductivity. Thus, we propose a scenario of fluctuating ferrimagnetic droplets immersed in a sea of QSL. This may be quite common on the way pursuing an ideal QSL, and provides a brand new platform to study how a QSL state survives impurities and coexists with other magnetically ordered states.

19.
J Food Sci ; 88(8): 3577-3593, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37458288

RESUMO

This study explores potential hypoglycemic mechanisms by preparing and identifying novel dipeptidyl peptidase IV (DPP-IV) inhibitory peptides from goat milk (GM) whey protein. Papain was used to hydrolyze the GM whey protein. After purification by ultrafiltration, the Sephadex column, and preparative RP-HPLC, the peptide inhibited DPP-IV, α-glucosidase, and α-amylase with IC50 of 0.34, 0.37, and 0.72 mg/mL, respectively. To further explore the inhibitory mechanism of peptides on DPP-IV, SPPEFLR, LDADGSY, YPVEPFT, and FNPTY were identified and synthesized for the first time, with IC50 values of 56.22, 52.16, 175.7, and 62.32 µM, respectively. Molecular docking and dynamics results show that SPPEFLR, LDADGSY, and FNPTY bind more tightly to the active pocket of DPP-IV, which was consistent with the in vitro activity. Furthermore, the first three N-terminals of SPPEFLR and FNPTY peptides exhibit proline characteristics and competitively inhibit DPP-IV. Notably, the first N-terminal leucine of LDADGSY may play a key role in inhibiting DPP-IV.


Assuntos
Inibidores da Dipeptidil Peptidase IV , Leite , Animais , Proteínas do Soro do Leite/metabolismo , Simulação de Acoplamento Molecular , Dipeptidil Peptidase 4/química , Inibidores da Dipeptidil Peptidase IV/farmacologia , Inibidores da Dipeptidil Peptidase IV/química , Peptídeos/química , Cabras
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