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1.
Nature ; 572(7770): 497-501, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31367036

RESUMO

Layered antiferromagnetism is the spatial arrangement of ferromagnetic layers with antiferromagnetic interlayer coupling. The van der Waals magnet chromium triiodide (CrI3) has been shown to be a layered antiferromagnetic insulator in its few-layer form1, opening up opportunities for various functionalities2-7 in electronic and optical devices. Here we report an emergent nonreciprocal second-order nonlinear optical effect in bilayer CrI3. The observed second-harmonic generation (SHG; a nonlinear optical process that converts two photons of the same frequency into one photon of twice the fundamental frequency) is several orders of magnitude larger than known magnetization-induced SHG8-11 and comparable to the SHG of the best (in terms of nonlinear susceptibility) two-dimensional nonlinear optical materials studied so far12,13 (for example, molybdenum disulfide). We show that although the parent lattice of bilayer CrI3 is centrosymmetric, and thus does not contribute to the SHG signal, the observed giant nonreciprocal SHG originates only from the layered antiferromagnetic order, which breaks both the spatial-inversion symmetry and the time-reversal symmetry. Furthermore, polarization-resolved measurements reveal underlying C2h crystallographic symmetry-and thus monoclinic stacking order-in bilayer CrI3, providing key structural information for the microscopic origin of layered antiferromagnetism14-18. Our results indicate that SHG is a highly sensitive probe of subtle magnetic orders and open up possibilities for the use of two-dimensional magnets in nonlinear and nonreciprocal optical devices.

2.
Proc Natl Acad Sci U S A ; 119(52): e2203894119, 2022 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-36534812

RESUMO

The gut microbiota and liver cancer have a complex interaction. However, the role of gut microbiome in liver tumor initiation remains unknown. Herein, liver cancer was induced using hydrodynamic transfection of oncogenes to explore liver tumorigenesis in mice. Gut microbiota depletion promoted liver tumorigenesis but not progression. Elevated sterol regulatory element-binding protein 2 (SREBP2) was observed in mice with gut flora disequilibrium. Pharmacological inhibition of SREBP2 or Srebf2 RNA interference attenuated mouse liver cancer initiation under gut flora disequilibrium. Furthermore, gut microbiota depletion impaired gut tryptophan metabolism to activate aryl hydrocarbon receptor (AhR). AhR agonist Ficz inhibited SREBP2 posttranslationally and reversed the tumorigenesis in mice. And, AhR knockout mice recapitulated the accelerated liver tumorigenesis. Supplementation with Lactobacillus reuteri, which produces tryptophan metabolites, inhibited SREBP2 expression and tumorigenesis in mice with gut flora disequilibrium. Thus, gut flora disequilibrium promotes liver cancer initiation by modulating tryptophan metabolism and up-regulating SREBP2.


Assuntos
Disbiose , Microbioma Gastrointestinal , Neoplasias Hepáticas , Proteína de Ligação a Elemento Regulador de Esterol 2 , Animais , Camundongos , Carcinogênese , Neoplasias Hepáticas/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo , Triptofano/metabolismo , Disbiose/complicações
3.
Chem Soc Rev ; 53(12): 6042-6067, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38770558

RESUMO

A steady stream of material transport based on carriers and channels in living systems plays an extremely important role in normal life activities. Inspired by nature, researchers have extensively applied supramolecular cages in cargo transport because of their unique three-dimensional structures and excellent physicochemical properties. In this review, we will focus on the development of supramolecular cages as carriers and channels for cargo transport in abiotic and biological systems over the past fifteen years. In addition, we will discuss future challenges and potential applications of supramolecular cages in substance transport.

4.
Nano Lett ; 24(43): 13811-13818, 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-39417603

RESUMO

Alloy-type anodes used in magnesium ion batteries (MIBs) have garnered significant attention in light of their substantial theoretical specific capacities and possible matchability with conventional electrolytes. However, the major challenges for alloy-type anodes are the sluggish transport kinetics as well as severe volume variations during the discharge/charge processes. Herein, we present a strategy for phase-structure modulation to fabricate a self-supporting In-Bi film through straightforward magnetron sputtering. In comparison to the single-phase In and Bi electrodes, the biphase InBi/Bi electrode displays markedly enhanced rate and cycling performance, with the discharge capacities of 303.1/292.6 mAh g-1 after 550/500 cycles at 200/2000 mA g-1, respectively. The exceptional Mg storage capability of the sputtered InBi/Bi electrode could be ascribed to the favorable two-phase configuration and increased phase boundaries, effectively accommodating volume expansion and accelerating Mg2+ ion transport. More importantly, the (de)magnesiation mechanism of InBi/Bi for MIBs was elucidated through operando X-ray diffraction.

5.
J Am Chem Soc ; 146(30): 21017-21024, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39029108

RESUMO

The devastating COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has made society acutely aware of the urgency in developing effective techniques to timely monitor the outbreak of previously unknown viral species as well as their mutants, which could be even more lethal and/or contagious. Here, we report a fluorogenic sensor array consisting of peptides truncated from the binding domain of human angiotensin-converting enzyme 2 (hACE2) for SARS-CoV-2. A set of five fluorescently tagged peptides were used to construct the senor array in the presence of different low-dimensional quenching materials. When orthogonally incubated with the wild-type SARS-CoV-2 and its variants of concern (VOCs), the fluorescence of each peptide probe was specifically recovered, and the different recovery rates provide a "fingerprint" characteristic of each viral strain. This, in turn, allows them to be differentiated from each other using principal component analysis. Interestingly, the classification result from our sensor array agrees well with the evolutionary relationship similarity of the VOCs. This study offers insight into the development of effective sensing tools for highly contagious viruses and their mutants based on rationally truncating peptide ligands from human receptors.


Assuntos
Enzima de Conversão de Angiotensina 2 , COVID-19 , Corantes Fluorescentes , Peptídeos , SARS-CoV-2 , Enzima de Conversão de Angiotensina 2/metabolismo , Enzima de Conversão de Angiotensina 2/química , SARS-CoV-2/enzimologia , SARS-CoV-2/isolamento & purificação , Humanos , Peptídeos/química , Peptídeos/metabolismo , Corantes Fluorescentes/química , COVID-19/virologia , COVID-19/diagnóstico , Técnicas Biossensoriais/métodos
6.
Br J Cancer ; 130(6): 925-933, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38238428

RESUMO

BACKGROUND: The diagnosis of follicular thyroid carcinoma (FTC) prior to surgery remains a major challenge in the clinic. METHODS: This multicentre diagnostic study involved 41 and 150 age- and sex-matched patients in the training cohort and validation cohort, respectively. The diagnostic properties of circulating small extracellular vesicle (sEV)-associated and cell-free RNAs were compared by RNA sequencing in the training cohort. Subsequently, using a quantitative real-time polymerase chain reaction (qRT‒PCR) assay, high-quality candidates were identified to construct an RNA classifier for FTC and verified in the validation cohort. The parallel expression, stability and influence of the RNA classifier on surgical strategy were also investigated. RESULTS: The diagnostic properties of sEV long RNAs, cell-free long RNAs and sEV microRNAs (miRNAs) were comparable and superior to those of cell-free miRNAs in RNA sequencing. Given the clinical application, the circulating sEV miRNA (CirsEV-miR) classifier was developed from five miRNAs based on qRT‒PCR data, which could well identify FTC patients (area under curve [AUC] of 0.924 in the training cohort and 0.844 in the multicentre validation cohort). Further tests revealed that the CirsEV-miR score was significantly correlated with the tumour burden, and the levels of sEV miRNAs were also higher in sEVs from the FTC cell line, organoid and tissue. Additionally, circulating sEV miRNAs remained constant after different treatments, and the addition of the CirsEV-miR classifier as a biomarker improves the current surgical strategy. CONCLUSIONS: The CirsEV-miR classifier could serve as a noninvasive, convenient, specific and stable auxiliary test to help diagnose FTC following ultrasonography.


Assuntos
Adenocarcinoma Folicular , Vesículas Extracelulares , MicroRNAs , Neoplasias da Glândula Tireoide , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Adenocarcinoma Folicular/diagnóstico , Adenocarcinoma Folicular/genética , Adenocarcinoma Folicular/metabolismo , Biomarcadores , Vesículas Extracelulares/metabolismo , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/metabolismo
7.
Small ; 20(35): e2401528, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38634219

RESUMO

The role of tannins (TA), a well-known abundant and ecologically friendly chelating ligand, in metal capture has long been studied. Different kinds of TA-containing adsorbents are synthesized for uranium capture, while most adsorbents suffer from unfavorable adsorption kinetics. Herein, the design and preparation of a TA-containing 2D crosslinked network adsorbent (TANP) is reported. The ≈1.8-nanometer-thick TANP films curl up into micrometer-scale pores, which contribute to fast mass transfer and full exposure of active sites. The coordination environment of uranyl (UO2 2+) ions is explored by integrated analysis of U L3-edge XANES and EXAFS. Density functional theory calculations indicate the energetically favorable UO2 2+ binding. Consequently, TANP with excellent adsorption kinetics presents a high uranium capture capacity (14.62 mg-U g-Ads-1) and a high adsorption rate (0.97 mg g-1 day-1) together with excellent selectivity and biofouling resistance. Life cycle assessment and cost analysis demonstrate that TANP has tremendous potential for application in industrial-scale uranium extraction from seawater.

8.
Small ; 20(37): e2401510, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38745545

RESUMO

To simulate life's emergent functions, mining the multiple sensing capabilities of nanosystems, and digitizing networks of transduction signals and molecular interactions, is an ongoing endeavor. Here, multifunctional antimonene-silver nanocomposites (AM-Ag NCs) are synthesized facilely and fused for molecular sensing and digitization applications (including ultra-multi-mode and multi-analyte sensing, parallel and batch logic computing, long-text information protection). By mixing surfactant, AM, Ag+ and Sodium borohydride (NaBH4) at room temperature for 5 min, the resulting NCs are comprised of Ag nanoparticles scattered within AM nanosheets and protected by the surfactant. Interestingly, AM-Ag NCs exhibit ultra-multi-mode sensing ability for multiplex metal ions (Hg2+, Fe3+, or Al3+), which significantly improved selectivity (≈2 times) and sensitivity (≈400 times) when analyzing the combined channels. Moreover, multiple sensing capabilities of AM-Ag NCs enable diverse batch and parallel molecular logic computations (including advanced cascaded logic circuits). Ultra-multi-mode selective patterns of AM-Ag NCs to 18 kinds of metal ions can be converted into a series of binary strings by setting the thresholds, and realized high-density, long-text information protection for the first time. This study provides new ideas and paradigms for the preparation and multi-purpose application of 2D nanocomposites, but also offers new directions for the fusion of molecular sensing and informatization.

9.
Small ; 20(11): e2307396, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37888791

RESUMO

Rechargeable magnesium batteries (RMBs) are considered as one of the most promising candidates for next-generation batteries. However, the popularization of RMBs is seriously plagued due to the lack of suitable non-nucleophilic electrolytes and the passivation of Mg anode. Herein, a novel non-nucleophilic electrolyte is developed by introducing (s)-1-methoxy-2-propylamine (M4) into themagnesium aluminum chloride complex (MACC)-like electrolyte. The as-synthesizes Mg(AlCl4 )2 -IL-DME-M4 electrolyte enables robust reversible cycling of Mg plating/stripping with low overpotential, high anodic stability, and ionic conductivity (8.56 mS cm-1 ). These features should be mainly attributed to the in situ formation of an MgF2 containing Mg2+ -conducting interphase, which dramatically suppresses the passivation and parasitic reaction of Mg anode with electrolyte. Remarkably, the Mg/S batteries assemble with as-synthesize electrolyte and a new type MoS2 @CMK/S cathode deliver unprecedented electrochemical performance. Specifically, the Mg/S battery exhibited the highest reversible capacity up to 1210 mAh g-1 at 0.1 C, excellent rate capability and satisfactory long-term cycling stability with a reversible capacity of 370 mAh g-1 (coulombic efficiency of ≈100%) at 1.0 C for 600 cycles. The study findings provide a novel strategy and inspiration for designing efficient non-nucleophilic Mg electrolyte and suitable sulfur-host materials for practical Mg/S battery applications.

10.
J Transl Med ; 22(1): 484, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773604

RESUMO

BACKGROUND: The aim of this study was to conduct an in silico analysis of a novel compound heterozygous variant in breast cancer susceptibility gene 2 (BRCA2) to clarify its structure-function relationship and elucidate the molecular mechanisms underlying triple-negative breast cancer (TNBC). METHODS: A tumor biopsy sample was obtained from a 42-year-old Chinese woman during surgery, and a maxBRCA™ test was conducted using the patient's whole blood. We obtained an experimentally determined 3D structure (1mje.pdb) of the BRCA2 protein from the Protein Data Bank (PDB) as a relatively reliable reference. Subsequently, the wild-type and mutant structures were predicted using SWISS-MODEL and AlphaFold, and the accuracy of these predictions was assessed through the SAVES online server. Furthermore, we utilized a high ambiguity-driven protein-protein docking (HADDOCK) algorithm and protein-ligand interaction profiler (PLIP) to predict the pathogenicity of the mutations and elucidate pathogenic mechanisms that potentially underlies TNBC. RESULTS: Histological examination revealed that the tumor biopsy sample exhibited classical pathological characteristics of TNBC. Furthermore, the maxBRCA™ test revealed two compound heterozygous BRCA2 gene mutations (c.7670 C > T.pA2557V and c.8356G > A.pA2786T). Through performing in silico structural analyses and constructing of 3D models of the mutants, we established that the mutant amino acids valine and threonine were located in the helical domain and oligonucleotide binding 1 (OB1), regions that interact with DSS1. CONCLUSION: Our analysis revealed that substituting valine and threonine in the helical domain region alters the structure and function of BRCA2 proteins. This mutation potentially affects the binding of proteins and DNA fragments and disrupts interactions between the helical domain region and OB1 with DSS1, potentially leading to the development of TNBC. Our findings suggest that the identified compound heterozygous mutation contributes to the clinical presentation of TNBC, providing new insights into the pathogenesis of TNBC and the influence of compound heterozygous mutations in BRCA2.


Assuntos
Proteína BRCA2 , Simulação por Computador , Mutação , Humanos , Feminino , Adulto , Mutação/genética , Proteína BRCA2/genética , Proteína BRCA2/química , Proteína BRCA2/metabolismo , Simulação de Acoplamento Molecular , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Genes BRCA2 , Sequência de Bases
11.
BMC Microbiol ; 24(1): 294, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39107680

RESUMO

The colonization of alien plants in new habitats is typically facilitated by microorganisms present in the soil environment. However, the diversity and structure of the archaeal, bacterial, and fungal communities in the latitudinal spread of alien plants remain unclear. In this study, the rhizosphere and bulk soil of Chromolaena odorata were collected from five latitudes in Pu' er city, Yunnan Province, followed by amplicon sequencing of the soil archaeal, bacterial, and fungal communities. Alpha and beta diversity results revealed that the richness indices and the structures of the archaeal, bacterial, and fungal communities significantly differed along the latitudinal gradient. Additionally, significant differences were observed in the bacterial Shannon index, as well as in the structures of the bacterial and fungal communities between the rhizosphere and bulk soils. Due to the small spatial scale, trends of latitudinal variation in the archaeal, bacterial, and fungal communities were not pronounced. Total potassium, total phosphorus, available nitrogen, available potassium and total nitrogen were the important driving factors affecting the soil microbial community structure. Compared with those in bulk soil, co-occurrence networks in rhizosphere microbial networks presented lower complexity but greater modularity and positive connections. Among the main functional fungi, arbuscular mycorrhizae and soil saprotrophs were more abundant in the bulk soil. The significant differences in the soil microbes between rhizosphere and bulk soils further underscore the impact of C. odorata invasion on soil environments. The significant differences in the soil microbiota along latitudinal gradients, along with specific driving factors, demonstrate distinct nutrient preferences among archaea, bacteria, and fungi and indicate complex microbial responses to soil nutrient elements following the invasion of C. odorata.


Assuntos
Archaea , Bactérias , Chromolaena , Fungos , Microbiota , Rizosfera , Microbiologia do Solo , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Fungos/classificação , Fungos/genética , Fungos/isolamento & purificação , Chromolaena/microbiologia , Archaea/classificação , Archaea/genética , Archaea/isolamento & purificação , China , Espécies Introduzidas , Biodiversidade , Solo/química , Raízes de Plantas/microbiologia , Filogenia
12.
Ann Surg Oncol ; 31(2): 1232-1242, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37930500

RESUMO

BACKGROUND: Intrahepatic cholangiocarcinoma (ICC) constitutes a group of heterogeneous malignancies within the liver. We sought to subtype ICC based on anatomical origin of tumors, as well as propose modifications of the current classification system. METHODS: Patients undergoing curative-intent resection for ICC, hilar cholangiocarcinoma (CCA), or hepatocellular carcinoma (HCC) were identified from three international multi-institutional consortia of databases. Clinicopathological characteristics and survival outcomes were assessed. RESULTS: Among 1264 patients with ICC, 1066 (84.3%) were classified as ICC-peripheral subtype, whereas 198 (15.7%) were categorized as ICC-perihilar subtype. Compared with ICC-peripheral subtype, ICC-perihilar subtype was more often associated with aggressive tumor characteristics, including a higher incidence of nodal metastasis, macro- and microvascular invasion, perineural invasion, as well as worse overall survival (OS) (median: ICC-perihilar 19.8 vs. ICC-peripheral 37.1 months; p < 0.001) and disease-free survival (DFS) (median: ICC-perihilar 12.8 vs. ICC-peripheral 15.2 months; p = 0.019). ICC-perihilar subtype and hilar CCA had comparable OS (19.8 vs. 21.4 months; p = 0.581) and DFS (12.8 vs. 16.8 months; p = 0.140). ICC-peripheral subtype tumors were associated with more advanced tumor features, as well as worse survival outcomes versus HCC (OS, median: ICC-peripheral 37.1 vs. HCC 74.3 months; p < 0.001; DFS, median: ICC-peripheral 15.2 vs. HCC 45.5 months; p < 0.001). CONCLUSIONS: ICC should be classified as ICC-perihilar and ICC-peripheral subtype based on distinct clinicopathological features and survival outcomes. ICC-perihilar subtype behaved more like carcinoma of the bile duct (i.e., hilar CCA), whereas ICC-peripheral subtype had features and a prognosis more akin to a primary liver malignancy.


Assuntos
Neoplasias dos Ductos Biliares , Carcinoma Hepatocelular , Colangiocarcinoma , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/patologia , Colangiocarcinoma/patologia , Prognóstico , Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos/patologia
13.
Opt Lett ; 49(8): 2117-2120, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38621090

RESUMO

The characterization of inverted structures (crystallographic, ferroelectric, or magnetic domains) is crucial in the development and application of novel multi-state devices. However, determining these inverted structures needs a sensitive probe capable of revealing their phase correlation. Here a contrast-enhanced phase-resolved second harmonic generation (SHG) microscopy is presented, which utilizes a phase-tunable Soleil-Babinet compensator and the interference between the SHG fields from the inverted structures and a homogeneous reference. By this means, such inverted structures are correlated through the π-phase difference of SHG, and the phase difference is ultimately converted into the intensity contrast. As a demonstration, we have applied this microscopy in two scenarios to determine the inverted crystallographic domains in two-dimensional van der Waals material MoS2. Our method is particularly suitable for applying in vacuum and cryogenic environments while providing optical diffraction-limited resolution and arbitrarily adjustable contrast. Without loss of generality, this contrast-enhanced phase-resolved SHG microscopy can also be used to resolve other non-centrosymmetric inverted structures, e.g. ferroelectric, magnetic, or multiferroic phases.

14.
BMC Cancer ; 24(1): 717, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38862932

RESUMO

BACKGROUNDS: To compare the efficacy and safety of transcatheter arterial chemoembolization (TACE) combined Lenvatinib plus Camrelizumab (TLC) in unresectable hepatocellular carcinoma (uHCC) with those of TACE alone . METHODS: A retrospective analysis was performed on 222 patients with uHCC who were treated between September 2013 and Jun 2023. One group received TACE + lenvatinib + camrelizumab (TLC) (n = 97) and another group received TACE alone (n = 151). Efficacy and safety were compared after propensity score matching between the TLC and TACE groups. RESULTS: After propensity matching, the TLC group had higher objective response rate (ORR) (88.6% vs. 28.6%, P < 0.001), disease control rate (DCR) (94.3%% vs. 72.9%, P < 0.001), and conversion rates before and after propensity matching were 44.1% and 41.4%, respectively, compared with the TACE group. The median progression free survival (PFS) was longer in the TLC group than in the TACE group (12.7 vs. 6.1 months, P = 0.005). The median overall survival (OS) was longer in the TLC group than in the TACE group (19.4 vs. 13.0 months, P = 0.023). Cox multivariate analysis with different modes of adjustment showed that treatment was an independent influencing factor of PFS and OS. The interaction analysis showed that cirrhosis and Child-Pugh stage an interactive role in the PFS of different treatment. Decreased AFP after treatment portends higher ORR and DCR. CONCLUSION: TACE combined Lenvatinib plus Camrelizumab regimen was safe and superior to TACE alone in improving PFS, OS, and tumor response rates for unresectable recurrent HCC patients.


Assuntos
Anticorpos Monoclonais Humanizados , Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Compostos de Fenilureia , Pontuação de Propensão , Quinolinas , Humanos , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Quinolinas/uso terapêutico , Quinolinas/administração & dosagem , Quinolinas/efeitos adversos , Masculino , Feminino , Quimioembolização Terapêutica/métodos , Quimioembolização Terapêutica/efeitos adversos , Pessoa de Meia-Idade , Estudos Retrospectivos , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/administração & dosagem , Compostos de Fenilureia/uso terapêutico , Compostos de Fenilureia/administração & dosagem , Compostos de Fenilureia/efeitos adversos , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Resultado do Tratamento , Terapia Combinada , Adulto
15.
Langmuir ; 2024 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-39471246

RESUMO

Developing fouling-resistant materials is of paramount interest in marine industries and biomedical applications. In this work, we studied the interfacial hydration and surface-protein interactions of the amphiphilic brush surface functionalized with hybrid hydrophilic trimethylamine N-oxide (TMAO) and hydrophobic pentafluoroethyl groups using a combination of atomistic molecular dynamics simulations and free-energy computations. Our results show that while the interfacial hydration density of the amphiphilic surface slightly decreases with the introduction of small fluorocarbons compared to that of the pure TMAO-functionalized surface, the amphiphilic surface remains relatively strong in resisting protein adsorption. The nanosized clustering of hydrophobic fluorine atoms on the top of the amphiphilic brush surface introduces weak protein adsorption; however, due to the strong interfacial hydration and weak hydrophobic interaction, the amphiphilic surface exhibits sufficient antibiofouling activities. Our fundamental studies will be critical for the discovery of marine fouling-resistant coating surfaces.

16.
Soft Matter ; 20(24): 4765-4775, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38841820

RESUMO

Silicones have excellent material properties and are used extensively in many applications, ranging from adhesives and lubricants to electrical insulation. To ensure strong adhesion of silicone adhesives to a wide variety of substrates, silane-based adhesion promotors are typically blended into the silicone adhesive formulation. However, little is known at the molecular level about the true silane adhesion promotion mechanism, which limits the ability to develop even more effective adhesion promoters. To understand the adhesion promotion mechanism of silane molecules at the molecular level, this study has used sum frequency generation vibrational spectroscopy (SFG) to determine the behavior of (3-glycidoxypropyl)trimethoxy silane (γ-GPS) at the buried interface between poly(ethylene terephthalate) (PET) and a bulk silicone adhesive. To complement and extend the SFG results, atomistic molecular dynamics (MD) simulations were applied to investigate molecular behavior and interfacial interaction of γ-GPS at the silicone/PET interface. Free energy computations were used to study the γ-GPS interaction in the sample system and determine the γ-GPS interfacial segregation mechanism. Both experiments and simulations consistently show that γ-GPS molecules prefer to segregate at the interface between PET and PDMS. The methoxy groups on γ-GPS molecules orient toward the PDMS polymer phase. The consistent picture of interfacial structure emerging from both simulation and experiment provides enhanced insight on how γ-GPS behaves in the silicone - PET system and illustrates why γ-GPS could improve the adhesion of silicone adhesive, leading to further understanding of silicone adhesion mechanisms useful in the design of silicone adhesives with improved performance.

17.
Arch Virol ; 169(7): 139, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38849620

RESUMO

Amdoparvoviruses infect various carnivores, including mustelids, canids, skunks, and felids. Aleutian mink disease virus (AMDV) belongs to the prototypical species Amdoparvovirus carnivoran1. Here, we identified a novel amdoparvovirus in farmed Asian badgers (Meles meles), and we named this virus "Meles meles amdoparvovirus" (MMADV). A total of 146 clinical samples were collected from 134 individual badgers, and 30.6% (41/134) of the sampled badgers tested positive for amdoparvovirus by PCR. Viral DNA was detected in feces, blood, spleen, liver, lung, and adipose tissue from these animals. Viral sequences from eight samples were determined, five of which represented nearly full-length genome sequences (4,237-4,265 nt). Six serum samples tested positive by PCR, CIEP, and IAT, four of which had high antibody titers (> 512) against AMDV-G. Twenty-six of the 41 amdoparvovirus-positive badgers showed signs of illness, and necropsy revealed lesions in their organs. Sequence comparisons and phylogenetic analysis of the viral NS1 and VP2 genes of these badger amdoparvoviruses showed that their NS1 proteins shared 62.6%-88.8% sequence identity with known amdoparvoviruses, and they clustered phylogenetically into two related clades. The VP2 proteins shared 76.6%-97.2% identity and clustered into two clades, one of which included raccoon dog and arctic fox amdoparvovirus (RFAV), and the other of which did not include other known amdoparvoviruses. According to the NS1-protein-based criterion for parvovirus species demarcation, the MMADV isolate from farm YS should be classified as a member of a new species of the genus Amdoparvovirus. In summary, we have discovered a novel MMADV and other badger amdoparvoviruses that naturally infect Asian badgers and are possibly pathogenic in badgers.


Assuntos
Vírus da Doença Aleutiana do Vison , Mustelidae , Filogenia , Animais , Mustelidae/virologia , Vírus da Doença Aleutiana do Vison/genética , Vírus da Doença Aleutiana do Vison/isolamento & purificação , Vírus da Doença Aleutiana do Vison/classificação , DNA Viral/genética , Genoma Viral/genética , Infecções por Parvoviridae/veterinária , Infecções por Parvoviridae/virologia , Doença Aleutiana do Vison/virologia , Doença Aleutiana do Vison/epidemiologia , Anticorpos Antivirais/sangue
18.
Phys Chem Chem Phys ; 26(8): 6582-6589, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38329233

RESUMO

Allosteric regulation is common in protein-protein interactions and is thus promising in drug design. Previous experimental and simulation work supported the presence of allosteric regulation in the SARS-CoV-2 spike protein. Here the route of allosteric regulation in SARS-CoV-2 spike protein is examined by all-atom explicit solvent molecular dynamics simulations, contrastive machine learning, and the Ohm approach. It was found that peptide binding to the polybasic cleavage sites, especially the one at the first subunit of the trimeric spike protein, activates the fluctuation of the spike protein's backbone, which eventually propagates to the receptor-binding domain on the third subunit that binds to ACE2. Remarkably, the allosteric regulation routes starting from the polybasic cleavage sites share a high fraction (39-67%) of the critical amino acids with the routes starting from the nitrogen-terminal domains, suggesting the presence of an allosteric regulation network in the spike protein. Our study paves the way for the rational design of allosteric antibody inhibitors.


Assuntos
COVID-19 , Humanos , Glicoproteína da Espícula de Coronavírus/metabolismo , SARS-CoV-2/metabolismo , Sítios de Ligação , Ligação Proteica , Regulação Alostérica , Simulação de Dinâmica Molecular
19.
BMC Endocr Disord ; 24(1): 125, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39054438

RESUMO

BACKGROUND: Parathyroid carcinoma (PC) is a rare malignancy, often diagnosed incidentally through postoperative pathological examination. The occurrence of nodular goiter, intrathyroidal parathyroid carcinoma, contralateral parathyroid adenoma (PA), and papillary thyroid microcarcinoma (PTMC) is extremely uncommon, which prompted us to report our case experience. CASE PRESENTATION: We describe a 67-year-old male who presented with a cervical mass causing tracheal compression, which prompted him to seek medical advice. Based on preoperative auxiliary examination results from color Doppler ultrasound, SPECT parathyroid imaging, and blood tests, he was initially diagnosed with a suspected parathyroid adenoma and nodular goiter. Excision of the right lobe and isthmus of the thyroid, and left superior parathyroid gland was conducted, which were sent to intraoperative frozen pathological examination. During intraoperative observation, adhesion around the right thyroid lobe was discovered. Consequently, right central area lymph node dissection was performed due to suspicion of an aggressive malignant tumor. Histology and immunohistochemistry analysis revealed incidental intrathyroidal parathyroid carcinoma, contralateral parathyroid adenoma, classical papillary thyroid microcarcinoma, and nodular goiter. CONCLUSION: Parathyroid carcinoma should be highly suspected when extremely high levels of PTH and severe hypercalcemia are present, which cannot be simply explained by a preoperatively localized parathyroid adenoma, especially when suspicious malignant adhesion is found during intraoperative exploration. In cases where multifocal thyroid nodules are associated with increased uptake of 99Tc-sestamibi, the possibility of coexisting carcinomas should be considered, not only for thyroid malignancy but also for the potential presence of intrathyroidal parathyroid carcinoma.


Assuntos
Carcinoma Papilar , Hiperparatireoidismo Primário , Neoplasias Primárias Múltiplas , Neoplasias das Paratireoides , Neoplasias da Glândula Tireoide , Humanos , Masculino , Neoplasias das Paratireoides/cirurgia , Neoplasias das Paratireoides/patologia , Neoplasias das Paratireoides/diagnóstico por imagem , Neoplasias das Paratireoides/diagnóstico , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/cirurgia , Neoplasias da Glândula Tireoide/diagnóstico , Idoso , Carcinoma Papilar/patologia , Carcinoma Papilar/cirurgia , Carcinoma Papilar/diagnóstico , Carcinoma Papilar/diagnóstico por imagem , Hiperparatireoidismo Primário/cirurgia , Hiperparatireoidismo Primário/etiologia , Hiperparatireoidismo Primário/patologia , Hiperparatireoidismo Primário/diagnóstico , Neoplasias Primárias Múltiplas/patologia , Neoplasias Primárias Múltiplas/cirurgia , Neoplasias Primárias Múltiplas/diagnóstico , Achados Incidentais
20.
Cereb Cortex ; 33(4): 997-1013, 2023 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-35332914

RESUMO

A critical way for humans to acquire information is through language, yet whether and how language experience drives specific neural semantic representations is still poorly understood. We considered statistical properties captured by 3 different computational principles of language (simple co-occurrence, network-(graph)-topological relations, and neural-network-vector-embedding relations) and tested the extent to which they can explain the neural patterns of semantic representations, measured by 2 functional magnetic resonance imaging experiments that shared common semantic processes. Distinct graph-topological word relations, and not simple co-occurrence or neural-network-vector-embedding relations, had unique explanatory power for the neural patterns in the anterior temporal lobe (capturing graph-common-neighbors), inferior frontal gyrus, and posterior middle/inferior temporal gyrus (capturing graph-shortest-path). These results were relatively specific to language: they were not explained by sensory-motor similarities and the same computational relations of visual objects (based on visual image database) showed effects in the visual cortex in the picture naming experiment. That is, different topological properties within language and the same topological computations (common-neighbors) for language and visual inputs are captured by different brain regions. These findings reveal the specific neural semantic representations along graph-topological properties of language, highlighting the information type-specific and statistical property-specific manner of semantic representations in the human brain.


Assuntos
Mapeamento Encefálico , Encéfalo , Humanos , Mapeamento Encefálico/métodos , Idioma , Semântica , Lobo Temporal/patologia , Imageamento por Ressonância Magnética/métodos
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