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1.
Plant J ; 115(2): 452-469, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37026387

RESUMEN

Plasma membrane represents a critical battleground between plants and attacking microbes. Necrosis-and-ethylene-inducing peptide 1 (Nep1)-like proteins (NLPs), cytolytic toxins produced by some bacterial, fungal and oomycete species, are able to target on lipid membranes by binding eudicot plant-specific sphingolipids (glycosylinositol phosphorylceramide) and form transient small pores, causing membrane leakage and subsequent cell death. NLP-producing phytopathogens are a big threat to agriculture worldwide. However, whether there are R proteins/enzymes that counteract the toxicity of NLPs in plants remains largely unknown. Here we show that cotton produces a peroxisome-localized enzyme lysophospholipase, GhLPL2. Upon Verticillium dahliae attack, GhLPL2 accumulates on the membrane and binds to V. dahliae secreted NLP, VdNLP1, to block its contribution to virulence. A higher level of lysophospholipase in cells is required to neutralize VdNLP1 toxicity and induce immunity-related genes expression, meanwhile maintaining normal growth of cotton plants, revealing the role of GhLPL2 protein in balancing resistance to V. dahliae and growth. Intriguingly, GhLPL2 silencing cotton plants also display high resistance to V. dahliae, but show severe dwarfing phenotype and developmental defects, suggesting GhLPL2 is an essential gene in cotton. GhLPL2 silencing results in lysophosphatidylinositol over-accumulation and decreased glycometabolism, leading to a lack of carbon sources required for plants and pathogens to survive. Furthermore, lysophospholipases from several other crops also interact with VdNLP1, implying that blocking NLP virulence by lysophospholipase may be a common strategy in plants. Our work demonstrates that overexpressing lysophospholipase encoding genes have great potential for breeding crops with high resistance against NLP-producing microbial pathogens.


Asunto(s)
Lisofosfolipasa , Verticillium , Lisofosfolipasa/genética , Gossypium/genética , Peroxisomas , Fitomejoramiento , Enfermedades de las Plantas/microbiología , Resistencia a la Enfermedad/genética , Regulación de la Expresión Génica de las Plantas
2.
Small ; : e2405068, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39077978

RESUMEN

The function-oriented synthesis of polyoxometalate (POM) nanoclusters has become an increasingly important area of research. Herein, the well-known broad-spectrum anticancer drug Ge-132 which contains GeIV as potential heteroatoms and carboxyl coordination sites, is introduced to the POM system, leading to the first organogermanium functionalized GeIV-SbIII-templating POM nanocluster Na4[H2N(CH3)2]16 H18[Sm4(H2O)12W4O14Ge(CH2CH2COOH)]2[SbW9O33]4[Ge(CH2CH2COOH) SbW15O54]2·62H2O (1). An unprecedented organogermanium templating Dawson-like [Ge(CH2CH2COOH)SbW15O54]12- building block is discovered. To take advantage of the potential pharmaceutical activity of such an organogermanium-functionalized POM cluster, 1 is further composited with gold nanoparticles (NPs) to prepare 1-Au NPs, which doubles the blood circulation time of 1-based nanodrug. Efficient separation of photogenerated charges in 1-Au NPs largely boosts the photothermal conversion efficiency (PCE = 55.0%), which is nearly 2.1 times that of either single 1 (PCE = 26.7%) or Au NPs (PCE = 26.2%), and simultaneously facilitate the generation of toxic activate reactive oxygen species in tumor microenvironment. Based on these findings, it is demonstrated that 1-Au NPs are a multifunctional and renal clearable nanomedicine with great potential in photoacoustic imaging guiding photothermal-chemodynamic therapy for breast cancer.

3.
J Chem Phys ; 160(21)2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38828813

RESUMEN

Computational modeling of plasmon-mediated molecular photophysical and photochemical behaviors can help us better understand and tune the bound molecular properties and reactivity and make better decisions to design and control nanostructures. However, computational investigations of coupled plasmon-molecule systems are challenging due to the lack of accurate and efficient protocols to simulate these systems. Here, we present a hybrid scheme by combining the real-time time-dependent density functional theory (RT-TDDFT) approach with the time-domain frequency dependent fluctuating charge (TD-ωFQ) model. At first, we transform ωFQ in the frequency-domain, an atomistic electromagnetic model for the plasmonic response of plasmonic metal nanoparticles (PMNPs), into the time-domain and derive its equation-of-motion formulation. The TD-ωFQ introduces the nonequilibrium plasmonic response of PMNPs and atomistic interactions to the electronic excitation of the quantum mechanical (QM) region. Then, we combine TD-ωFQ with RT-TDDFT. The derived RT-TDDFT/TD-ωFQ scheme allows us to effectively simulate the plasmon-mediated "real-time" electronic dynamics and even the coupled electron-nuclear dynamics by combining them with the nuclear dynamics approaches. As a first application of the RT-TDDFT/TD-ωFQ method, we study the nonradiative decay rate and plasmon-enhanced absorption spectra of two small molecules in the proximity of sodium MNPs. Thanks to the atomistic nature of the ωFQ model, the edge effect of MNP on absorption enhancement has also been investigated and unveiled.

4.
Nanotechnology ; 33(49)2022 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-36067729

RESUMEN

The number of MXene layers plays a crucial role in their performance when they are used as anode materials for sodium-ion batteries. Herein, Ti-based nitride MXenes with different layers, TixNx-1O2MXene (x= 2, 3, 4) structures, were constructed to calculate the structural stability of their precursor, electronic properties after etching, and sodium storage behavior compared with the common Ti2CO2and Ti3C2O2MXene. First-principles calculations indicate that nitride MXenes possess a better rate capability than carbide MXenes of the same thickness. Moreover, the barrier for Na diffusion on the Ti2NO2MXene surface (0.114 eV) is lowest. Meanwhile, comparing the properties of three nitride MXenes with different thicknesses, Ti2NO2MXene performs relatively well with a high theoretical capacity with 756 mAh g-1and a lower open circuit voltage of 1.1 V. In conclusion, the performance improvement of nitride MXene is not linear with thickness, because that of Ti3N2O2MXene is relatively weaker. This work lays the foundation for the feasibility of Ti3N2Txexperimental preparation and provides corresponding evidence on the choice of MXene thickness. More attention should be paid to the etching method for Ti2NTxMXene.

5.
Sheng Li Xue Bao ; 74(6): 970-978, 2022 Dec 25.
Artículo en Zh | MEDLINE | ID: mdl-36594385

RESUMEN

The aim of this study was to explore the regulating effects of hyperoside (Hyp) on lipid metabolism in high-fat diet mice. The high-fat diet mouse model was established by high-fat diet induction. After 5 weeks of Hyp intragastric administration in high-fat diet mice, the serum lipid levels before and after Hyp administration were measured by the corresponding kits. The tissue structure of mouse liver was observed by HE staining before and after Hyp administration. The changes of intestinal flora and transcriptome were measured by Illumina platforms. Liquid chromatography-mass spectrometry (LC-MS) was used to determine non-targeted metabolites. The results showed that Hyp significantly reduced lipid levels in the high-fat diet mice and effectively restored the external morphology and internal structure of liver tissue. Hyp changed the species composition of the intestinal flora in high-fat diet mice, increased the abundance of beneficial flora such as Ruminococcus, and decreased the abundance of harmful flora such as Sutterella. Combined multi-omics analysis revealed that the effect of retinoic acid on lipid metabolism was significant in the high-fat diet mice treated with Hyp, while the increase of retinoic acid content was significantly negatively correlated with the expression of genes such as cyp1a2 and ugt1a6b, positively correlated with AF12 abundance, and significantly negatively correlated with unidentified_Desulfovibrionaceae abundance. These results suggest that Hyp may modulate the abundance of AF12, unidentified_Desulfovibrionaceae and inhibit the expression of genes such as cyp1a2 and ugt1a6b, thus increasing the content of retinoic acid and regulating lipid metabolism in the high-fat diet mice.


Asunto(s)
Dieta Alta en Grasa , Metabolismo de los Lípidos , Animales , Ratones , Dieta Alta en Grasa/efectos adversos , Citocromo P-450 CYP1A2/metabolismo , Citocromo P-450 CYP1A2/farmacología , Multiómica , Hígado , Lípidos/farmacología , Tretinoina/metabolismo , Tretinoina/farmacología , Ratones Endogámicos C57BL
6.
Angew Chem Int Ed Engl ; 60(51): 26592-26598, 2021 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-34719865

RESUMEN

The sluggish oxygen reaction kinetics concomitant with the high overpotentials and parasitic reactions from cathodes and solvents is the major challenge in aprotic lithium-oxygen (Li-O2 ) batteries. Herein, PtIr multipods with a low Lewis acidity of the Pt atoms are reported as an advanced cathode for improving overpotentials and stabilities. DFT calculations disclose that electrons have a strong disposition to transfer from Ir to Pt, since Pt has a higher electronegativity than Ir, resulting in a lower Lewis acidity of the Pt atoms than that on the pure Pt surface. The low Lewis acidity of Pt atoms on the PtIr surface entails a high electron density and a down-shifting of the d-band center, thereby weakening the binding energy towards intermediates (LiO2 ), which is the key in achieving low oxygen-reduction-reaction (ORR) and oxygen-evolution-reaction (OER) overpotentials. The Li-O2 cell based on PtIr electrodes exhibits a very low overall discharge/charge overpotential (0.44 V) and an excellent cycle life (180 cycles), outperforming the bulk of reported noble-metal-based cathodes.

7.
J Thorac Dis ; 16(5): 3228-3250, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38883620

RESUMEN

Background: The preoperative differential diagnosis of nodular lung adenocarcinoma has long been a challenging issue for thoracic surgeons. This study aimed to explore differential diagnosis of nodular lung adenocarcinoma by comprehensively analyzing its clinical, computed tomography (CT) imaging, and postoperative pathological and genetic features. Methods: The clinical, CT imaging, and postoperative pathological features of different classifications of nodular lung adenocarcinoma were retrospectively analyzed through univariate and multivariate statistical methods. Results: There were 132 patients with nodular lung adenocarcinoma enrolled. Firstly, compared with ground-glass nodular lung adenocarcinoma, solid nodular lung adenocarcinoma was more common in women [odds ratio (OR), 3.662; 95% confidence interval (CI): 1.066-12.577] and older adults (OR, 1.061; 95% CI: 1.007-1.119), and CT signs were mostly lobulation (OR, 4.957; 95% CI: 1.714-14.337) and spiculation (OR, 8.214; 95% CI: 2.740-24.621); the mean CT (CTm) value of solid nodular lung adenocarcinoma was significantly higher than that of ground-glass nodular lung adenocarcinoma, and the optimal diagnostic threshold was -267.5 Hounsfield units (HU). Secondly, the maximum diameter of nodule size (NSmax) of invasive adenocarcinoma (IAC) was significantly greater than that of minimally IAC (MIA; OR, 6.306; 95% CI: 1.191-33.400) or atypical adenomatous hyperplasia (AAH)/adenocarcinoma in situ (AIS; OR, 189.539; 95% CI: 4.720-7,610.476), and the optimal diagnostic threshold between IAC and MIA was 1.35 cm; the CTm value of IAC was significantly higher than that of MIA, and the optimal diagnostic threshold was -460.75 HU. Thirdly, lepidic-predominant adenocarcinoma (LPA) manifest more commonly as pure ground-glass nodule (pGGN; OR, 6.252; 95% CI: 1.429-27.358) or mixed ground-glass nodule (mGGN; OR, 4.224; 95% CI: 1.223-14.585). Moreover, the mutation rate of epidermal growth factor receptor (EGFR) in IAC was 70.69% (41/58). The EGFR mutation rates of mGGNs (OR, 8.794; 95% CI: 1.489-51.933) and solid nodules (SNs; OR, 12.912; 95% CI: 1.597-104.383) were significantly higher than that of pGGNs. Furthermore, compared with those of micropapillary-predominant adenocarcinoma (MPA), solid-predominant adenocarcinoma (SPA), or invasive mucinous adenocarcinoma (IMA), there were significantly higher EGFR mutation rates in acinar-predominant adenocarcinoma/papillary-predominant adenocarcinoma (APA/PPA; OR, 55.925; 95% CI: 4.045-773.284) and LPA (OR, 38.265; 95% CI: 2.307-634.596). Conclusions: Different classifications of nodular lung adenocarcinoma have their own clinicopathological and CT imaging features, and the latter is the main predictor.

8.
J Colloid Interface Sci ; 668: 335-342, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38678888

RESUMEN

Membrane receptors perform a diverse range of cellular functions, accounting for more than half of all drug targets. The mechanical microenvironment regulates cell behaviors and phenotype. However, conventional analysis methods of membrane receptors often ignore the effects of the extracellular matrix stiffness, failing to reveal the heterogeneity of cell membrane receptors expression. Herein, we developed an in-situ surface-enhanced Raman scattering (SERS) imaging method to visualize single-cell membrane receptors on substrates with different stiffness. Two SERS substrates, Au@4-mercaptobenzonitrile@Ag@Sgc8c and Au@4-pethynylaniline@Ag@SYL3c, were employed to specifically target protein tyrosine kinase-7 (PTK7) and epithelial cell adhesion molecule (EpCAM), respectively. The polyacrylamide (PA) gels with tunable stiffness (2.5-25 kPa) were constructed to mimic extracellular matrix. The simultaneous SERS imaging of dual membrane receptors on single cancer cells on substrates with different stiffness was achieved. Our findings reveal decreased expression of PTK7 and EpCAM on cells cultured on stiffer substrates and higher migration ability of the cells. The results elucidate the heterogeneity of membrane receptors expression of cells cultured on the substrates with different stiffness. This single-cell analysis method offers an in-situ platform for investigating the impacts of extracellular matrix stiffness on the expression of membrane receptors, providing insights into the role of cell membrane receptors in cancer metastasis.


Asunto(s)
Molécula de Adhesión Celular Epitelial , Matriz Extracelular , Análisis de la Célula Individual , Espectrometría Raman , Matriz Extracelular/metabolismo , Humanos , Molécula de Adhesión Celular Epitelial/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Oro/química , Resinas Acrílicas/química , Plata/química , Propiedades de Superficie , Línea Celular Tumoral , Compuestos de Anilina/química , Tamaño de la Partícula , Moléculas de Adhesión Celular
9.
Talanta ; 271: 125697, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38295449

RESUMEN

Therapeutic drug monitoring (TDM) is an important tool in precision medicine as it allows estimating pharmacodynamic and pharmacokinetic effects of drugs in clinical settings. An accurate, fast and real-time determination of the drug concentrations in patients ensures fast decision-making processes at the bedside to optimize the clinical treatment. Surface-enhanced Raman spectroscopy (SERS), which is based on the application of metallic nanostructured substrates to amplify the inherent weak Raman signal, is a promising technique in medical research due to its molecular specificity and trace sensitivity accompanied with short detection times. Therefore, we developed a SERS-based detection scheme using silicon nanowires decorated with silver nanoparticles, fabricated by means of top-down etching combined with chemical deposition, to detect the antibiotic ceftriaxone (CRO) in spiked fresh plasma and microdialysis samples. We successfully detected CRO in both matrices with an LOD of 94 µM in protein-depleted fresh plasma and 1.4 µM in microdialysate.


Asunto(s)
Nanopartículas del Metal , Nanocables , Humanos , Antibacterianos/farmacología , Plata/química , Ceftriaxona , Silicio/química , Nanopartículas del Metal/química , Nanocables/química , Espectrometría Raman/métodos
10.
Small Methods ; : e2400336, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38517268

RESUMEN

Industrializing water electrolyzers demands better electrocatalysts, especially for the anodic oxygen evolution reaction (OER). The prevailing OER catalysts are Ir or Ru-based nanomaterials, however, they still suffer from insufficient stability. An alternative yet considerably less explored approach is to upgrade Rh, a known stable but moderately active element for OER electrocatalysis, via rational structural engineering. Herein, a precise synthesis of assembled RhRuFe trimetallenes (RhRuFe TMs) with an average thickness of 1 nm for boosting overall water splitting catalysis is reported. Favorable mass transport and optimized electronic structure collectively render RhRuFe TMs with an improved OER activity of an overpotential of 330 mV to deliver 10 mA cm-2, which is significantly lower than the Rh/C control (by 601 mV) and reported Rh-based OER electrocatalysts. In particular, the RhRuFe TMs-based water splitting devices can achieve the current density of 10 mA cm-2 at a low voltage of 1.63 V, which is among the best in the Rh-based bifunctional catalysts for electrolyzers. The addition of Fe in RhRuFe TMs can modulate the strain/electron distribution of the multi-alloy, which regulates the binding energies of H* and OH* in hydrogen and oxygen evolution reactions for achieving the enhanced bifunctional OER and HER catalysis is further demonstrated.

11.
ACS Sens ; 8(11): 4307-4314, 2023 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-37923556

RESUMEN

Matrix metalloproteinase-9 (MMP-9), a proteolytic enzyme, degrades the extracellular matrix and plays a key role in cell communication. However, the real-time monitoring of cell-secreted MMP-9 during cell-cell communication remains a challenge. Herein, we developed a cell-based membrane-anchored surface-enhanced Raman scattering (SERS) biosensor using a Au@4-mercaptobenzonitrile (4-MBN) @Ag@peptide nanoprobe for the monitoring of cell-secreted MMP-9 during cell communication. The multifunctional nanoprobe was created with Au@4-MBN@Ag acting as an interference-free SERS substrate with high enhancement in which the peptide not only serves to anchor the cell membrane but also provides MMP-9-activatable cleaved peptide chains. MMP-9-mediated cleavage resulted in the detachment of the Au@4-MBN@Ag nanoparticles from the cell membrane, thereby decreasing the SERS signals of cancer cells. The cell membrane-anchored SERS biosensor enables the real-time monitoring of cell-secreted MMP-9 during the interaction of MCF-7 and HUVEC cells. This study successfully demonstrates the dynamic change of cell-secreted MMP-9 during the communication between MCF-7 cells and HUVEC cells. The proposed nanoprobe was also utilized to precisely evaluate the breast and hepatoma cancer cell aggressiveness. This study provides a novel strategy for real-time monitoring of MMP-9 secretion during cell communication, which is promising for the investigation of the mechanisms underlying different tumor processes.


Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Humanos , Metaloproteinasa 9 de la Matriz , Plata , Membrana Celular , Péptidos
12.
Talanta ; 253: 123900, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36095940

RESUMEN

Research on ion channels and their monoclonal antibodies plays a critical role in drug development and disease diagnosis. The current ion channel researches are often not conducted in the microenvironment for cells survival, which restricts the mechanism study of the links between the cell structure and the ion channel function. In this work, we synthesized gold core-4-mercaptobenzonitrile-sliver shell-goat anti-rabbit immunoglobulin G (Au@4-MBN@Ag@IgG) nanoparticles as surface-enhanced Raman scattering (SERS) nanoprobes for investigating the human ether-a-go-go related gene (hERG) potassium ion channel in cell membranes. This is the first attempt to study ion channels using SERS. Due to the unique core-molecule-shell structure and the silver shell of nanoprobes, strong and stable SERS signal was obtained. With the help of antibodies, the Au@4-MBN@Ag@IgG nanoprobes were captured by hERG antibodies and then bonded with hERG ion channels based on the sandwich immune response. The reporter molecule, 4-MBN, displayed a strong and sharp characteristic peak at 2233 cm-1 in the Raman silent region. The intensity of this peak denoted the concentration of antibodies and the expression of ion channel proteins. We successfully applied this amplification-free method for in-situ imaging the distribution of the hERG ion channel on the transfected HEK293 cell surface at the single-cell level. This hERG ion channel profiling strategy promises a maneuverable tool for ion channel research.


Asunto(s)
Inmunoglobulina G , Canales Iónicos , Humanos , Células HEK293 , Nanopartículas del Metal
13.
Adv Mater ; 35(29): e2211854, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36731862

RESUMEN

Advancing electrocatalysts for alkaline hydrogen oxidation/evolution reaction (HOR/HER) is essential for anion exchange membrane-based devices. The state-of-the-art Pt-based electrocatalysts for alkaline HOR suffer from low intrinsic activities and severe CO poisoning due to the challenge of simultaneously optimizing surface adsorption toward different adsorbates. Herein, this challenge is overcome by tuning an atomic MoOx layer with high oxophilicity onto PtMo nanoparticles (NPs) with optimized Had , OHad , and COad adsorption for boosting anti-CO-poisoning hydrogen-cycle electrocatalysis in alkaline media. For alkaline HOR, this catalyst exhibits high kinetics and an exchange current density of 3.19 mA µgPt -1 at 50 mV versus reversible hydrogen electrode and 0.83 mA cmPt -2 , 10.3- and 3.8-fold higher than those of commercial Pt/C, respectively. For alkaline HER, it achieves an unprecedented overpotential of 37 mV at 10 mA cm-2 . Experimental and theoretical studies show that the orchestrated electronic and oxophilic regulation of the PtMo/MoOx interface NPs simultaneously optimizes Had and OHad adsorption for boosting alkaline hydrogen electrocatalysis, whereas reactive oxygen from the amorphous MoOx atomic layer lowers the CO oxidation reaction barrier, leading to superior anti-poisoning ability even at 100 ppm CO.

14.
Adv Mater ; 35(32): e2302285, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37248040

RESUMEN

Strain engineering has been utilized as an effective approach to regulate the binding of reaction intermediates and modify catalytic behavior on noble metal nanocatalysts. However, the continuous, precise control of strain for a depiction of strain-activity correlation remains a challenge. Herein, Pd-based nanooctahedrons coated with two Ir overlayers are constructed, and subject to different postsynthetic treatments to alter the amount of H intercalated into Pd core for achieving three different surface strains (o-Pd/Ir-1.2%, o-Pd/Ir-1.7%, and o-Pd/Ir-2.1% NPs). It is demonstrated that the catalytic performances of o-Pd/Ir NPs display a volcano-shaped curve against strains toward the hydrogen evolution reaction (HER). Specifically, o-Pd/Ir-1.7% NPs exhibit superior catalytic performance with a mass activity of 9.38 A mgIr -1 at -0.02 V versus reversible hydrogen electrode, 10.8- and 18.8-fold higher than those of commercial Pt/C and Ir/C, respectively, making it one of the most active HER electrocatalysts reported to date. Density function theory calculations verify that the moderate tensile strain on Ir(111) surfaces plays a pivotal role in optimizing the H binding energy. This work highlights a new strategy for precise control over the surface strain of nanocrystals for more efficient electrocatalysis.

15.
Chirality ; 24(7): 552-7, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22566128

RESUMEN

The enantioselective degradation of quizalofop-ethyl and its metabolite quizalofop-acid in two soils, a Wuhan acidic soil and a Baoding alkaline soil, was investigated. The dissipation of quizalofop-ethyl consisted of two phases, a rapidly deceasing first phase that lasted 1 day and a slowly decreasing second phase that extended till the end of the incubation. It is shown that S-quizalofop-ethyl degraded slightly faster than R-quizalofop-ethyl in the two soils. Further incubation of enantiopure enaniomers showed that quizalofop-ethyl was configurationally stable in soil. Quizalofop-acid was produced quickly, and its amount reached a maximum at 1-6 days time and then decreased slowly with half-lives ranging from 11 to 21 days. The results also showed that quizalofop-acid degraded faster in the acidic Wuhan soil than in the alkaline Baoding soil. At last, significant enantiomerization from S-quizalofop-acid to R-quizalofop-acid was observed, and the enantiomerization was fast, resulting in residues enriched with R-quizalofop-acid whatever racemic quizalofop-ethyl or pure enantiomers were initially applied in the soils.


Asunto(s)
Propionatos/química , Quinoxalinas/química , Suelo/química , Concentración de Iones de Hidrógeno , Propionatos/metabolismo , Quinoxalinas/metabolismo , Estereoisomerismo , Especificidad por Sustrato
16.
Zhonghua Bing Li Xue Za Zhi ; 41(2): 102-6, 2012 Feb.
Artículo en Zh | MEDLINE | ID: mdl-22455886

RESUMEN

OBJECTIVE: To study the clinicopathologic features, criteria for grading and prognostic factors of primary hepatic neuroendocrine neoplasms. METHODS: Thirty-five cases of primary hepatic neuroendocrine neoplasm were retrieved from the archival files over a period of 11 years (with 32 cases having integrated data). According to the 2010 WHO classification of tumors of the digestive system, the cases were categorized into three groups: neuroendocrine tumor grade 1 (NET G1), neuroendocrine tumor grade 2 (NET G2) and neuroendocrine carcinoma (NEC). Statistical correlation between various histologic parameters and survival data was analyzed. RESULTS: Statistical analysis showed significant difference between NET [G1 (1 case)/G2 (14 cases)] and NEC (17 cases) groups in terms of tumor differentiation, necrosis, nuclear atypia, mitotic count and Ki-67 proliferative index (P < 0.05). There was no statistically significant difference in tumor size, growth pattern and presence of vascular tumor emboli (P > 0.05). The survival rate of patients correlated with tumor differentiation, growth pattern, necrosis, nuclear atypia, mitotic count and proliferative index (P < 0.05). There was no statistically significant difference between patient survival and tumor size or presence of vascular tumor emboli (P > 0.05). CONCLUSIONS: The subdivision of primary hepatic neuroendocrine neoplasm according to the 2010 WHO classification of tumors of the digestive system helps to evaluate the malignant potential and prognosis of the tumors. Prognostically useful histologic parameters include tumor differentiation, growth pattern, necrosis, nuclear atypia, mitotic count and proliferative index.


Asunto(s)
Carcinoma Neuroendocrino/patología , Neoplasias Hepáticas/patología , Tumores Neuroendocrinos/patología , Adulto , Anciano , Carcinoma Neuroendocrino/inmunología , Femenino , Estudios de Seguimiento , Humanos , Antígeno Ki-67/metabolismo , Neoplasias Hepáticas/clasificación , Neoplasias Hepáticas/inmunología , Masculino , Persona de Mediana Edad , Tumores Neuroendocrinos/clasificación , Tumores Neuroendocrinos/inmunología , Tasa de Supervivencia
17.
Comput Methods Programs Biomed ; 215: 106634, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35081497

RESUMEN

BACKGROUND AND OBJECTIVE: Colorectal cancer (CRC) is currently one of the main cancers world-wide, with a high incidence in the elderly. In the diagnosis of CRC, endorectal ultrasound plays an important role in judging benign and early malignant tumors. However, malignant tumors in the early-stage are not easy to identify visually and experts usually seek help from multi-view images, which increases the workload and also exists a certain probability of misdiagnosis. In recent years, with the widespread use of deep learning methods in the analysis of medical images, it becomes necessary to design an effective computer-aided diagnosis (CAD) system of CRC based on multi-view endorectal ultrasound images. METHOD: In this study, we proposed a CAD system for judging benign and early malignant colorectal tumors, and constructed the first multi-view ultrasound image dataset of CRC to validate our algorithm. Our system is an end-to-end model based on a deep neural network (DNN) which includes a feature extraction module based on dense blocks, a multi-view fusion module, and a Multi-Layer Perception-based classifier. A center loss was used for the first time in CAD tasks, to optimize our model. RESULT: On the constructed dataset, the proposed system surpasses expert diagnosis in accuracy, sensitivity, specificity, and F1-score. Compared with the popular deep classification networks and other CAD methods, the algorithm has reached the best performance. Comparative experiments using different feature extraction methods, different view fusion strategies, and different classifiers verify the effectiveness of each part of the algorithm. CONCLUSION: We propose a CAD system for judging benign and early malignant colorectal tumors based on DNN, which combines information of ultrasound images from different views for comprehension. On the first CRC multi-view ultrasound image dataset which we constructed, our method outperforms expert diagnosis results and all other methods, and the effectiveness of each part of the system has been verified. Our system has application value in future medical practice on early diagnosis of CRC.


Asunto(s)
Neoplasias Colorrectales , Juicio , Anciano , Neoplasias Colorrectales/diagnóstico por imagen , Diagnóstico por Computador , Humanos , Redes Neurales de la Computación , Ultrasonografía
18.
Anal Chim Acta ; 1189: 339224, 2022 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-34815036

RESUMEN

Psoralen ultraviolet A (PUVA) therapy has thrived as a promising treatment for psoriasis. However, overdose of PUVA treatment will cause side-effects, such as melanoma formation. And these side-effects are often ignored during PUVA therapy. Hence, in situ monitoring therapeutic response of PUVA therapy is important to minimize side-effects. Aberrant expression of tyrosinase (TYR) has been proved to be associated with melanoma, indicating that TYR is a potential target for evaluation of PUVA therapy. Herein, we reported a strategy for in situ monitoring TYR activity during PUVA therapy by using a cell-array chip-based SERS platform. The cell-array chip was used to simulate cell survival environment for cell culture. Capture of single cells and living cell analysis were realized in the isolated microchambers. An enzyme-induced core-shell self-assembly substrate was used to evaluate TYR activity in living cells during PUVA therapy. The gold nanoparticle modified with a SERS reporter, 4-mercaptobenzonitrile (4-MBN), was used as the core. In the presence of oxygen and TYR, hydroxylation of l-tyrosine occurred, leading to the reduction of silver ion on the surface of gold cores. The growth of silver shells was accompanied by the increased SERS intensity of the reporter, which is related directly to TYR activity. The detection limit for TYR activity is 0.45 U/mL. Upregulation of TYR activity was successfully monitored after PUVA therapy. Notably, real-time and in situ information of therapeutic response can be obtained through monitoring PUVA therapy by using a cell-array chip-based SERS platform, which has great potential to guide the clinical application of PUVA therapy.


Asunto(s)
Oro , Nanopartículas del Metal , Terapia PUVA , Animales , Línea Celular , Ratones , Plata , Espectrometría Raman
19.
Colloids Surf B Biointerfaces ; 215: 112490, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35405536

RESUMEN

Theranostic nanoplatforms with accurate diagnosis and effective therapy show a bright prospect for tumor treatments. Herein, a novel boracic acid-modified graphite carbon nitride and Prussian blue nanohybrid (PB@B-g-C3N4) was developed, which provides sialic acid-targeted Raman recognition and synergistic photothermal/photodynamic therapy in the near-infrared region. Owing to the specific interaction between boracic acid and sialic acid and Raman response at 2157 cm-1 of PB, the nanohybrids exhibit high specificity and Raman sensitivity for detection of the overexpressed sialic acid on tumor cells. Moreover, the photothermal conversion efficiency of PB@B-g-C3N4 is as high as 47.0% with 808 nm laser irradiation due to the enhanced absorbance of PB@B-g-C3N4. PB@B-g-C3N4 also possesses excellent photodynamic activity, which is attributed to the energy transfer of PB (type I) and electron transfer between PB and B-g-C3N4 (type II). This nanotheranostic agent for Raman recognition of cancer markers and synergistic photothermal/photodynamic therapy holds great potential for the development of efficient theranostic nanoplatforms.


Asunto(s)
Neoplasias , Fotoquimioterapia , Ferrocianuros , Humanos , Ácido N-Acetilneuramínico , Neoplasias/terapia , Fototerapia/métodos
20.
Adv Mater ; 34(27): e2202084, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35484940

RESUMEN

Moderate adsorption of oxygenated intermediates takes a significant role in rational design of high-efficiency oxygen reduction reaction (ORR) electrocatalysts. Long-serving as a reliable strategy to tune geometric structure of nanomaterials, defect engineering enjoys the great ability of adjusting the coordination environment of catalytic active sites, which enables dominant regulation of adsorption energy and kinetics of ORR catalysis. However, limited to controllable nanocrystals fabrication, inducing uniformly dispersed high-coordinated defects into ultrathin 2D nanosheets remains challenging. Herein, atomic-scale cavities (ASCs) are proposed as a new kind of high-coordinated active site and successfully introduced into suprathin Pd (111)-exposed metallene. Due to its atomic concave architecture, leading to elevated CN and moderately downshifted d-band center, the as-made Pd metallene with ASCs (c-Pd M) exhibits excellent ORR performance with mass activity of 2.76 A mgPd -1 at 0.9 V versus reversible hydrogen electrode (RHE) and half-wave potential as high as 0.947 V, which is 18.9 (2.7) times higher and 104 (46) mV larger than that of commercial Pt/C (Pd metallene without ASCs). Besides, the durability of c-Pd M exceeds its commercial counterpart with ≈30% loss after 5000 cycles. This work highlights a new-style mentality of designing fancy active sites toward efficient ORR electrocatalysis.

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