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1.
Heliyon ; 10(18): e37892, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39323857

RESUMEN

Jingdong 120-meter radio telescope (JRT) is poised to become the world's largest single-aperture fully steerable medium-low frequency radio telescope. However, like other large-aperture radio telescopes, the JRT is vulnerable to wind loads, which can cause structural deformation and pointing errors. Addressing this challenge requires the ability to predict dynamic winds in real-time. This study developed a wind pressure preprocessing and prediction model using sensor data collected from the Kunming 40-meter radio telescope (KRT), enabling real-time prediction of wind pressure on the telescope. The model employs adaptive noise and Variational Mode Decomposition (VMD) techniques to eliminate random noise from the original wind pressure data. Subsequently, wind pressure predictions are made using a Bidirectional Long Short-term Memory (BiLSTM) model. By conducting predictions under various stabilization conditions and conducting a thorough analysis of measurement data from five sensors, the study has achieved impressive results in predicting wind pressure on the KRT reflector surface. The proposed model demonstrates the lowest MAE, RMSE, and MAPE, while achieving the highest R 2 across various data sets. Where the average R 2 of the proposed model is 0.9392 at 45° pitch angle attitude and the RMSE, MAE and MAPE values are 1.4923, 1.2377 and 1.82% respectively. This model helps wind load monitoring of real-time wind pressure monitoring of the telescope surface, to study the effects of wind load on pointing accuracy. By adjusting the control parameters to reduce wind load interference, to ensure the high-precision work of a large radio telescope, such as JRT.

2.
BMC Health Serv Res ; 24(1): 1135, 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39334309

RESUMEN

BACKGROUND: China accounts for 24% of newly diagnosed cancer cases and 30% of cancer-related deaths worldwide. Comprehensive analyses of the economic burden on patients across different cancer treatment phases, based on empirical data, are lacking. This study aims to estimate the financial burden borne by patients and analyze the cost compositions of the leading cancers with the highest number of new cases in China. METHODS: This cross-sectional cost-of-illness study analyzed patients diagnosed with lung, breast, colorectal, esophageal, liver, or gastric cancer, identified through electronic health records (EHRs) from 84 hospitals across 17 provinces in China. Patients completed any one of the initial treatment phase, follow-up phase, and relapse/metastasis phase were recruited by trained attending physicians through a stratified sampling procedure to ensure enough cases for each cancer progression stage and cancer treatment phase. Direct and indirect costs by treatment phase were collected from the EHRs and self-reported surveys. We estimated per case cost for each type of cancer, and employed subgroup analyses and multiple linear regression models to explore cost drivers. RESULTS: We recruited a total of 13,745 cancer patients across three treatment phases. The relapse/metastasis phase incurred the highest per case costs, varying from $8,890 to $14,572, while the follow-up phase was the least costly, ranging from $1,840 to $4,431. Being in the relapse/metastasis phase and having an advanced clinical stage of cancer at diagnosis were associated with significantly higher cost, while patients with low socioeconomic status borne lower costs. CONCLUSIONS: There were substantial financial burden on patients with six leading cancers in China. Health policymakers should emphasize comprehensive healthcare coverage for marginalized populations such as the uninsured, less educated, and those living in underdeveloped regions.


Asunto(s)
Costo de Enfermedad , Neoplasias , Humanos , China/epidemiología , Estudios Transversales , Masculino , Femenino , Persona de Mediana Edad , Neoplasias/economía , Neoplasias/terapia , Anciano , Adulto , Costos de la Atención en Salud/estadística & datos numéricos , Gastos en Salud/estadística & datos numéricos
3.
BMC Cancer ; 24(1): 1148, 2024 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-39277718

RESUMEN

BACKGROUND: Breast cancer (BC) poses significant burdens on women globally. While past research suggests a potential link between bone mineral density (BMD) and BC risk, findings remain inconsistent. Our study aims to elucidate the causal relationship between BMD and BC in East Asians using bidirectional Mendelian randomization (MR). METHODS: Genetic association data for bone mineral density T-scores (BMD-T) and Z-scores (BMD-Z) (Sample size = 92,615) and BC from two different sources (Sample size1 = 98,283; Sample size2 = 79,550) were collected from publicly available genome-wide association studies (GWAS). Single-nucleotide polymorphisms (SNPs) associated with BMD-T and BMD-Z as phenotype-related instrumental variables (IVs) were used, with BC as the outcome. As the primary means of causal inference, the inverse variance weighted (IVW) approach was employed. Heterogeneity analysis was conducted using Cochran's Q test, while MR-Egger regression analysis was implemented to assess the pleiotropic effects of the IVs. Sensitivity analyses were performed using methods such as MR-Egger, weighted median, and weighted mode to analyze the robustness and reliability of the results. The MR-PRESSO method and the RadialMR were used to detect and remove outliers. The PhenoScanner V2 website was utilized to exclude confounding factors shared between BMD and BC. Besides, the Bonferroni correction was also used to adjust the significance threshold. Then, the meta-analysis method was applied to combine the MR analysis results from the two BC sources. Finally, a reverse MR analysis was conducted. RESULTS: The results of the IVW method were consolidated through meta-analysis, revealing a positive correlation between genetically predicted BMD-T ([Formula: see text], [Formula: see text], [Formula: see text]) and BMD-Z ([Formula: see text],[Formula: see text], [Formula: see text]) with increased BC risk. The Cochran's [Formula: see text] test and MR-Egger regression suggested that neither of these causal relationships was affected by heterogeneity or horizontal pleiotropy. The sensitivity analyses supported the IVW results, indicating the robustness of the findings. Reverse MR analysis showed no causal relationship between BC and BMD. CONCLUSION: Our MR study results provide evidence for the causal relationship between BMD and BC risk in East Asian populations, suggesting that BMD screening is of great significance in detecting and preventing BC.


Asunto(s)
Densidad Ósea , Neoplasias de la Mama , Femenino , Humanos , Densidad Ósea/genética , Neoplasias de la Mama/genética , Neoplasias de la Mama/epidemiología , Pueblos del Este de Asia , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Análisis de la Aleatorización Mendeliana , Polimorfismo de Nucleótido Simple , Factores de Riesgo
4.
J Am Chem Soc ; 146(31): 21677-21688, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39042557

RESUMEN

Achieving high guest loading and multiguest-binding capacity holds crucial significance for advancement in separation, catalysis, and drug delivery with synthetic receptors; however, it remains a challenging bottleneck in characterization of high-stoichiometry guest-binding events. Herein, we describe a large-sized coordination cage (MOC-70-Zn8Pd6) possessing 12 peripheral pockets capable of accommodating multiple guests and a high-resolution electrospray ionization mass spectrometry (HR-ESI-MS)-based method to understand the solution host-guest chemistry. A diverse range of bulky guests, varying from drug molecules to rigid fullerenes as well as flexible host molecules of crown ethers and calixarenes, could be loaded into open pockets with high capacities. Notably, these hollow cage pockets provide multisites to capture different guests, showing heteroguest coloading behavior to capture binary, ternary, or even quaternary guests. Moreover, a pair of commercially applied drugs for the combination therapy of chronic lymphocytic leukemia (CLL) has been tested, highlighting its potential in multidrug delivery for combined treatment.


Asunto(s)
Espectrometría de Masa por Ionización de Electrospray , Éteres Corona/química , Calixarenos/química , Paladio/química , Zinc/química , Fulerenos/química , Estructura Molecular
5.
Adv Sci (Weinh) ; 11(36): e2401182, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39051482

RESUMEN

Treatment of highly aggressive triple-negative breast cancer (TNBC) in the clinic is challenging. Here, a liposome nanodrug (LP@PFH@HMME) integrating imaging agents and therapeutic agents for bimodal imaging-guided sonodynamic therapy (SDT) is developed, which boosted immunogenicity to enable potent immunotherapy via immune checkpoint blockade (ICB) in TNBC. In the acidic tumor microenvironment (TME), LP@PFH@HMME undergoes "nano-to-micro" transformation due to a pH-responsive lipid fusion, which makes droplets much more sensitive to ultrasound (US) in contrast-enhanced ultrasound (CEUS) and SDT studies. The nanodrug demonstrates robust bimodal imaging ability through fluorine-19 magnetic resonance imaging (19F MRI) and CEUS bimodal imaging, and it exhibits excellent solubility in aqueous solution with relatively high 19F content and desirable long transverse relaxation time (T2 = 1.072 s), making it suitable for high-performance 19F MRI, in addition to effective accumulation of nanodrugs after tail vein injection. Thus, 19F MRI/CEUS dual imaging is achievable to show adequate time points for US irradiation of tumor sites to induce highly effective SDT, which produces abundant reactive oxygen species (ROS) triggering immunogenic cell death (ICD) to assist ICB-based immunotherapy. The combination treatment design of sonodynamic therapy with immunotherapy effectively inhibited TNBC growth and recurrence, highlighting the promise of multifunctional nanodrugs in treating TNBC.


Asunto(s)
Inhibidores de Puntos de Control Inmunológico , Neoplasias de la Mama Triple Negativas , Terapia por Ultrasonido , Neoplasias de la Mama Triple Negativas/terapia , Neoplasias de la Mama Triple Negativas/diagnóstico por imagen , Neoplasias de la Mama Triple Negativas/inmunología , Inhibidores de Puntos de Control Inmunológico/farmacología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Animales , Ratones , Femenino , Terapia por Ultrasonido/métodos , Humanos , Ultrasonografía/métodos , Modelos Animales de Enfermedad , Liposomas/química , Imagen por Resonancia Magnética con Fluor-19/métodos , Imagen por Resonancia Magnética/métodos , Medios de Contraste , Inmunoterapia/métodos , Línea Celular Tumoral , Microambiente Tumoral/inmunología , Microambiente Tumoral/efectos de los fármacos
6.
Adv Sci (Weinh) ; 11(34): e2406683, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38984397

RESUMEN

Given that tumor microenvironment (TME) exerts adverse impact on the therapeutic response and clinical outcome, robust TME modulators may significantly improve the curative effect and increase survival benefits of cancer patients. Here, Au nanodots-anchored CoFe2O4 nanoflowers with PEGylation (CFAP) are developed to respond to TME cues, aiming to exacerbate redox dyshomeostasis for efficacious antineoplastic therapy under ultrasound (US) irradiation. After uptake by tumor cells, CFAP with glucose oxidase (GOx)-like activity can facilitate glucose depletion and promote the production of H2O2. Multivalent elements of Co(II)/Co(III) and Fe(II)/Fe(III) in CFAP display strong Fenton-like activity for·OH production from H2O2. On the other hand, energy band structure CFAP is superior for US-actuated 1O2 generation, relying on the enhanced separation and retarded recombination of e-/h+ pairs. In addition, catalase-mimic CFAP can react with cytosolic H2O2 to generate molecular oxygen, which may increase the product yields from O2-consuming reactions, such as glucose oxidation and sonosensitization processes. Besides the massive production of reactive oxygen species, CFAP is also capable of exhausting glutathione to devastate intracellular redox balance. Severe immunogenic cell death and effective inhibition of solid tumor by CFAP demonstrates the clinical potency of such heterogeneous structure and may inspire more relevant designs for disease therapy.


Asunto(s)
Cobalto , Compuestos Férricos , Oro , Oxidación-Reducción , Microambiente Tumoral , Microambiente Tumoral/efectos de los fármacos , Cobalto/química , Oro/química , Compuestos Férricos/química , Animales , Ratones , Humanos , Nanopartículas del Metal/química , Homeostasis , Línea Celular Tumoral , Especies Reactivas de Oxígeno/metabolismo , Modelos Animales de Enfermedad , Peróxido de Hidrógeno/metabolismo
7.
Anal Chem ; 96(27): 10943-10952, 2024 07 09.
Artículo en Inglés | MEDLINE | ID: mdl-38918973

RESUMEN

Both controllable regulation of the conformational structure of a polypeptide and specific recognition of an amino acid are still arduous challenges. Here, a novel dual-mode (electrochemical and colorimetric) biosensor was built for arginine (Arg) recognition based on a conformation switch, utilizing controllable and synergistic self-assembly of a ferrocene-grafted hexadecapeptide (P16Fc) with gold nanoparticles (AuNPs). Benefiting from the flexibility and unique topological structure of P16Fc formed nanospheres, the assembly and disassembly can undergo a conformation transition induced by Arg through controlling the distance and number of Fc detached from the gold surface, producing on-off electrical signals. Also, they can induce aggregation and dispersion of AuNPs in solution, causing a color change. The mechanism of Arg recognition with polypeptide conformation regulation was well explored by combining microstructure characterizations with molecular mechanics calculations. The electrochemical and colorimetric assays for Arg were successfully established in sensitive and selective manner, not only obtaining a very low detection limit, but also effectively eliminating the interference from other amino acids and overcoming the limitation of AuNP aggregation. Notably, the conformational change-based assay with the peptide regulated by the target will make a powerful tool for the amino acid biosensing and health diagnosis.


Asunto(s)
Arginina , Técnicas Electroquímicas , Compuestos Ferrosos , Oro , Nanopartículas del Metal , Metalocenos , Péptidos , Arginina/química , Compuestos Ferrosos/química , Metalocenos/química , Oro/química , Nanopartículas del Metal/química , Péptidos/química , Técnicas Biosensibles/métodos , Colorimetría/métodos , Conformación Proteica , Límite de Detección
8.
Acta Biomater ; 183: 264-277, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38815685

RESUMEN

Tumor starvation therapy utilizing glucose oxidase (GOx), has gained traction due to its non-invasive and bio-safe attributes. However, its effectiveness is often hampered by severe hypoxia in the tumor microenvironment (TME), limiting GOx's catalytic activity. To address this issue, a multifunctional nanosystem based on mesoporous polydopamine nanoparticles (MPDA NPs) was developled to alleviate TME hypoxia. This nanosystem integrated GOx modification and oxygenated perfluoropentane (PFP) encapsulation to address hypoxia-related challenges in the TME. Under NIR laser irradiation, the MPDA NPs exhibit significant photothermal conversion efficacy, activating targeted tumor photothermal therapy (PTT), while also serving as proficient photoacoustic (PA) imaging agents. The ensuing temperature rise facilitates oxygen (O2) release and induces liquid-gas conversion of PFP, generating microbubbles for enhanced ultrasound (US) imaging signals. The supplied oxygen alleviates local hypoxia, thereby enhancing GOx-mediated endogenous glucose consumption for tumor starvation. Overall, the integration of ultrasound/photoacoustic dual imaging-guided PTT and starvation therapy within MPDA-GOx@PFP@O2 nanoparticles (MGPO NPs) presents a promising platform for enhancing the efficacay of tumor treatment by overcoming the complexities of the TME. STATEMENT OF SIGNIFICANCE: A multifunctional MPDA-based theranostic nanoagent was developed for US/PAI imaging-guided PTT and starvation therapy against tumor hypoxia by direct O2 delivery. The incorporation of oxygenated perfluoropentane (PFP) within the mesoporous structure of MGPO not only enables efficient US imaging but also helps in alleviating tumor hypoxia. Moreover, the strong near-infrared (NIR) absorption of MGPO NPs promote the generation of PFP microbubbles and release of oxygen, thereby enhancing US imaging and GOx-mediated starvation therapy. Such a multifunctional nanosystem leverages synergistic effects to enhance therapeutic efficacy while incorporating US/PA imaging for precise visualization of the tumor.


Asunto(s)
Nanopartículas , Técnicas Fotoacústicas , Nanomedicina Teranóstica , Técnicas Fotoacústicas/métodos , Animales , Nanomedicina Teranóstica/métodos , Ratones , Nanopartículas/química , Nanopartículas/uso terapéutico , Humanos , Línea Celular Tumoral , Fluorocarburos/química , Neoplasias/diagnóstico por imagen , Neoplasias/terapia , Porosidad , Terapia Fototérmica , Indoles/química , Polímeros/química , Glucosa Oxidasa/química , Ultrasonografía , Ratones Endogámicos BALB C , Ratones Desnudos , Oxígeno/química , Microambiente Tumoral/efectos de los fármacos , Femenino , Pentanos
9.
Angew Chem Int Ed Engl ; 63(1): e202313336, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-37983653

RESUMEN

The precise control of the regioselectivity in the transition metal-catalyzed migratory hydrofunctionalization of alkenes remains a big challenge. With a transient ketimine directing group, the nickel-catalyzed migratory ß-selective hydroarylation and hydroalkenylation of alkenyl ketones has been realized with aryl boronic acids using alkyl halide as the mild hydride source for the first time. The key to this success is the use of a diphosphine ligand, which is capable of the generation of a Ni(II)-H species in the presence of alkyl bromide, and enabling the efficient migratory insertion of alkene into Ni(II)-H species and the sequent rapid chain walking process. The present approach diminishes organosilanes reductant, tolerates a wide array of complex functionalities with excellent regioselective control. Moreover, this catalytic system could also be applied to the migratory hydroarylation of alkenyl azahetereoarenes, thus providing a general approach for the preparation of 1,2-aryl heteroaryl motifs with wide potential applications in pharmaceutical discovery.

10.
Acta Biomater ; 172: 454-465, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37863345

RESUMEN

Ultra-high-field (UHF) MRI has shown great advantages over low-field magnetic resonance imaging (MRI). Despite being the most commonly used MRI contrast agents, gadolinium chelates perform poorly in high magnetic fields, which significantly weakens their T1 intensity. In comparison, the rare element Holmium (Ho)-based nanoparticles (NPs) have demonstrated great potential as T2-weighted MRI contrast agents in UHF MRI due to their extremely short electron relaxation times (∼ 10-13s). In this study, a multifunctional nanotherapeutic probe was designed for UHF MRI-guided chemotherapy and photothermal therapy. The Ho (III)-doped mesoporous polydopamine (Ho-MPDA, HM) nanosphere was loaded with the chemotherapeutic drug mitoxantrone (MTO) and then coated with 4T1 cell membranes to enhance active targeting delivery to breast cancer. The prepared nanotherapeutic probe MTO@HMM@4T1 (HMM@T) exhibited good biocompatibility, high drug-loading capability and great potential as Ho (III)-based UHF MRI contrast agents. Moreover, the biodegradation of HMM@T in response to the intratumor pH and glutathione (GSH) promotes MTO release. Near-infrared (NIR) light irradiation of HM induced photothermal therapy and further enhanced drug release. Consequently, HMM@T effectively acted as an MRI-guided tumor-targeting chemo-photothermal therapy against 4T1 breast cancer. STATEMENT OF SIGNIFICANCE: Ultra-high-field (UHF) MRI has shown great advantages over low-field magnetic resonance imaging (MRI). Although gadolinium chelates are the most commonly used MRI contrast agents in clinical practice, they exhibit a significantly decreased T1 relaxivity at UHF. Holmium exhibits outstanding UHF magnetic resonance capabilities in comparison with gadolinium chelates currently used in clinic. Herein, a theranostic nanodrug (HMM@T) was designed for UHF MRI-guided chemo-photothermal therapy. The nanodrug possessed remarkable UHF T2 MRI properties (r2 = 152.13 mM-1s-1) and high drug loading capability of 18.4 %. The biodegradation of HMM@T NPs under triple stimulations of pH, GSH, and NIR led to an efficient release of MTO in tumor microenvironment. Our results revealed the potential of a novel UHF MRI-guided multifunctional nanosystem in cancer treatment.


Asunto(s)
Neoplasias de la Mama , Hipertermia Inducida , Nanopartículas , Humanos , Femenino , Holmio/farmacología , Terapia Fototérmica , Medios de Contraste/farmacología , Nanomedicina Teranóstica/métodos , Gadolinio/farmacología , Gadolinio/química , Fototerapia/métodos , Neoplasias de la Mama/tratamiento farmacológico , Imagen por Resonancia Magnética/métodos , Nanopartículas/química , Doxorrubicina/farmacología , Hipertermia Inducida/métodos , Microambiente Tumoral
11.
Sensors (Basel) ; 23(20)2023 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-37896629

RESUMEN

Due to the strong oxidizing properties of H2O2, excessive discharge of H2O2 will cause great harm to the environment. Moreover, H2O2 is also an energetic material used as fuel, with specific attention given to its safety. Therefore, it is of great importance to explore and prepare good sensitive materials for the detection of H2O2 with a low detection limit and high selectivity. In this work, a kind of hydrogen peroxide electrochemical sensor has been fabricated. That is, polypyrrole (PPy) has been electropolymerized on the glass carbon electrode (GCE), and then Ag and Cu nanoparticles are modified together on the surface of polypyrrole by electrodeposition. SEM analysis shows that Cu and Ag nanoparticles are uniformly deposited on the surface of PPy. Electrochemical characterization results display that the sensor has a good response to H2O2 with two linear intervals. The first linear range is 0.1-1 mM (R2 = 0.9978, S = 265.06 µA/ (mM × cm2)), and the detection limit is 0.027 µM (S/N = 3). The second linear range is 1-35 mM (R2 = 0.9969, 445.78 µA/ (mM × cm2)), corresponding to 0.063 µM of detection limit (S/N = 3). The sensor reveals good reproducibility (σ = 2.104), repeatability (σ = 2.027), anti-interference, and stability. The recoveries of the electrode are 99.84-103.00% (for 0.1-1 mM of linear range) and 98.65-104.80% (for 1-35 mM linear range). Furthermore, the costs of the hydrogen peroxide electrochemical sensor proposed in this work are reduced largely by using non-precious metals without degradation of the sensing performance of H2O2. This study provides a facile way to develop nanocomposite electrochemical sensors.

12.
JAMA Oncol ; 9(4): 465-472, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36821107

RESUMEN

Importance: Cancers are a leading cause of mortality, accounting for nearly 10 million annual deaths worldwide, or 1 in 6 deaths. Cancers also negatively affect countries' economic growth. However, the global economic cost of cancers and its worldwide distribution have yet to be studied. Objective: To estimate and project the economic cost of 29 cancers in 204 countries and territories. Design, Setting, and Participants: A decision analytical model that incorporates economic feedback in assessing health outcomes associated with the labor force and investment. A macroeconomic model was used to account for (1) the association of cancer-related mortality and morbidity with labor supply; (2) age-sex-specific differences in education, experience, and labor market participation of those who are affected by cancers; and (3) the diversion of cancer treatment expenses from savings and investments. Data were collected on April 25, 2022. Main Outcomes and Measures: Economic cost of 29 cancers across countries and territories. Costs are presented in international dollars at constant 2017 prices. Results: The estimated global economic cost of cancers from 2020 to 2050 is $25.2 trillion in international dollars (at constant 2017 prices), equivalent to an annual tax of 0.55% on global gross domestic product. The 5 cancers with the highest economic costs are tracheal, bronchus, and lung cancer (15.4%); colon and rectum cancer (10.9%); breast cancer (7.7%); liver cancer (6.5%); and leukemia (6.3%). China and the US face the largest economic costs of cancers in absolute terms, accounting for 24.1% and 20.8% of the total global burden, respectively. Although 75.1% of cancer deaths occur in low- and middle-income countries, their share of the economic cost of cancers is lower at 49.5%. The relative contribution of treatment costs to the total economic cost of cancers is greater in high-income countries than in low-income countries. Conclusions and Relevance: In this decision analytical modeling study, the macroeconomic cost of cancers was found to be substantial and distributed heterogeneously across cancer types, countries, and world regions. The findings suggest that global efforts to curb the ongoing burden of cancers are warranted.


Asunto(s)
Neoplasias , Masculino , Femenino , Humanos , Morbilidad , Neoplasias/epidemiología , Neoplasias/terapia , Escolaridad , China
13.
Chem Commun (Camb) ; 58(97): 13511-13514, 2022 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-36385370

RESUMEN

A practical method for regioselective hydroarylation of unactivated γ- or δ-vinyl alkylamines has been reported, enabling facile preparation of highly value-added ε- or ζ-aryl alkylamines. The protocol employs nickel catalysis, shows high functional group tolerance and can be used for modifying bio-related molecules.


Asunto(s)
Alquenos , Níquel
14.
Chem Commun (Camb) ; 58(83): 11709-11712, 2022 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-36178252

RESUMEN

A practical method for 1,2-diborylation of non-activated monosubstituted alkenes via nickel catalysis has been developed. The protocol features high functional group tolerance and can be applied for the formal synthesis of drugs and modification of natural product derivatives. Preliminary mechanistic studies imply the involvement of a Ni(II) catalytic cycle.


Asunto(s)
Alquenos , Productos Biológicos , Catálisis , Níquel
15.
Bioelectrochemistry ; 146: 108165, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35623273

RESUMEN

L-glutamate (L-Glu) has gained much attention owing to its contribution to the umami taste and it plays important roles in the central nervous system. Herein, an enzyme-free amperometric biosensor based on a peptide possessing an electroactive ferrocene linker as ferrocene-Gly-Gly-Gly-Gly-Ile- Pro-Val-Tyr-Cys-Gly-Leu-Ile-Gly-Gly-Gly-Gly-Lys-(CH2)4- thioctic acid self- assembled on gold electrode was designed and fabricated for specific determination of L-Glu. The biosensor was characterised via cyclic voltammetry, electrochemical impedance spectroscopy, atomic force microscopy and scanning electron microscopy. The biosensor showed optimum response within 200 s at 0.10 V in phosphate-buffered saline. Moreover, the biosensor exhibited excellent sensitivity and a low detection limit of 1.00 × 10-10 M. The sensitivity at an L-Glu concentration of 1.00 × 10-7 M - 1.00 × 10-3 M was 0.1572 µA/M, and that at an L-Glu concentration of 1.00 × 10-10 M - 1.00 × 10-7 M was 0.0293 µA/M. The peptide-based biosensor had excellent specificity and a wider linear range. The relative standard deviation of the L-Glu concentrations measured by the biosensor in a hundred-fold dilution of mouse serum samples was less than 5.00% compared with the high-performance liquid chromatography results, and the recovery rate of L-Glu was from 93.32% to 105.15%.


Asunto(s)
Aptámeros de Péptidos , Ácido Glutámico , Secuencia de Aminoácidos , Animales , Metalocenos , Ratones , Fragmentos de Péptidos , Péptidos , Tripsina
16.
Front Bioeng Biotechnol ; 10: 846446, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35433665

RESUMEN

Magnetic resonance imaging-guided high-intensity focused ultrasound (MRI-guided HIFU) is a non-invasive strategy of diagnosis and treatment that is applicable in tumor ablation. Here, we prepared a multifunctional nanotheranostic agent (SSPN) by loading perfluorohexane (PFH) and superparamagnetic iron oxides (SPIOs) in silica lipid for MRI-guided HIFU ablation of tumors. PFH was introduced to improve the ablation effect of HIFU and the ultrasound (US) contrast performance. Due to its liquid-to-gas transition characteristic, it is sensitive to temperature. SPIOs were used as an MRI contrast agent. Silica lipid was selected because it is a more stable carrier material compared with normal lipid. Previous studies have shown that SSPNs have good biocompatibility, stability, imaging, and therapeutic effects. Therefore, this system is expected to develop an important therapeutic agent for MRI-guided HIFU therapy against tumors.

17.
Adv Clin Exp Med ; 31(3): 307-315, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34856079

RESUMEN

BACKGROUND: Heterogeneity within the tumor may cause large heterogeneity in quantitative perfusion parameters. Three-dimensional contrast-enhanced ultrasound (3D-CEUS) can show the spatial relationship of vascular structure after post-acquisition reconstruction and monodisperse bubbles can resonate the ultrasound pulse, resulting in the increase in sensitivity of CEUS imaging. OBJECTIVES: To evaluate whether the combination of 3D-CEUS and monodisperse microbubbles could reduce the heterogeneity of quantitative CEUS. MATERIAL AND METHODS: Three in vitro perfusion models with perfusion volume ratio of 1:2:4 were set up. Both quantitative 2D-CEUS and 3D-CEUS were used to acquire peak intensity (PI) with 2 kinds of ultrasound agents. One was a new kind of monodisperse bubbles produced in this study, named Octafluoropropane-loaded cerasomal microbubbles (OC-MBs), the other was SonoVue®. The coefficient of variation (CV) was calculated to evaluate the cross-sectional variability. Pearson's correlation analysis was used to assess the correlation between weighted PIs (average of PIs of 3 different planes) and perfusion ratios. RESULTS: The average CVs of quantitative 3D-CEUS was slightly lower than that of 2D-CEUS (0.41 ±0.17 compared to 0.55 ±0.26, p = 0.3592). As for quantitative 3D-CEUS, the PI of the OC-MBs has shown better stability than that of SonoVue®, but without a significant difference (average CVs: 0.32 ±0.19 compared to 0.50 ±0.10, p = 0.0711). In the 2D-CEUS condition, the average CVs of OC-MBs group and SonoVue® group were 0.68 ±0.15 and 0.41 ±0.17 (p = 0.2747). As for 3D-CEUS condition, using OC-MBs group and SonoVue®, the r-values of the weighted PI and perfusion ratio were 0.8685 and 0.5643, respectively, while that of 2D-CEUS condition were 0.7760 and 0.3513, respectively. CONCLUSIONS: Our in vitro experiments showed that OC-MBs have the potential in acquiring more stable quantitative CEUS value, as compared to the SonoVue® in 3D-CEUS condition. The combination of 3D-CEUS and OC-MBs can reflect perfusion volume more precisely and may be a potential way to reduce quantitative heterogeneity.


Asunto(s)
Medios de Contraste , Microburbujas , Estudios Transversales , Ultrasonografía/métodos
18.
Front Physiol ; 12: 763478, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34916957

RESUMEN

Aims: The aim was to describe the incidence of atrial fibrillation (AF) after cavotricuspid isthmus (CTI) ablation in patients with typical atrial flutter (AFL) without history of AF and to identify risk factors for new-onset AF after the procedure. Methods: A total of 191 patients with typical AFL undergoing successful CTI ablation were enrolled. Patients who had history of AF, structural heart disease, cardiac surgery, or ablation or who received antiarrhythmic drug after procedure were excluded. Clinical and electrophysiological data were collected. Results: There were 47 patients (24.6%) developing new AF during a follow-up of 3.3 ± 1.9 years after CTI ablation. Receiver operating characteristic (ROC) curves indicated that the cut-off values of left atrial diameter (LAD) and CHA2DS2-VASc score were 42 mm and 2, with area under the curve of 0.781 and 0.550, respectively. The multivariable Cox regression analysis revealed that obstructive sleep apnea (OSA) [hazard ratio (HR) 3.734, 95% confidence interval (CI) 1.470-9.484, P = 0.006], advanced interatrial block (aIAB) (HR 2.034, 95% CI 1.017-4.067, P = 0.045), LAD > 42 mm (HR 2.710, 95% CI 1.478-4.969, P = 0.001), and CHA2DS2-VASc score > 2 (HR 2.123, 95% CI 1.118-4.034, P = 0.021) were independent risk factors of new-onset AF. Conclusion: A combination of OSA, aIAB, LAD > 42 mm, and CHA2DS2-VASc > 2 was a strongly high risk for new-onset AF after ablation for typical AFL, and it had significance in postablation management in clinical practice.

19.
Nanoscale ; 13(42): 17822-17836, 2021 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-34668898

RESUMEN

Near-infrared-II (NIR-II) cancer photothermal therapy (PTT) has become more and more attractive as the NIR-II light shows a higher tissue penetrating depth, which leads to better anti-cancer effects. Recently, the members of the MXene family have been reported as NIR-II photothermal agents, possessing a high specific surface area and a fascinating light-to-heat conversion rate at the same time. Herein, we reported a combination of NIR-II photothermal therapy and immune therapy based on the MXene family member niobium carbide (Nb2C). First, Nb2C nanosheets (NSs) under 50 nm were prepared. They showed a high photothermal conversion efficiency under a 1064-nm laser, and the NIR-II light showed a deeper tissue penetration depth. Then, a nanoplatform with high R837 stability and a high loading rate was obtained after modification with a polydopamine (PDA) layer on the surface of Nb2C. With the R837 modification, the percentage of mature dendritic cells (DCs) increased and the immune response enhanced, compared with the immune response caused by PTT only. Finally, a red blood cell (RBC) membrane was applied as a coat over the nanoplatform in order to avoid excessive blood clearance. During in vivo experiments, blood circulation of Nb2C@PDA-R837@RBC nanoparticles (NPs) was prolonged, and all primary tumors were eliminated. Secondary tumors were also inhibited effectively due to the strengthened immune response, proving that Nb2C@PDA-R837@RBC NPs could inhibit tumor recurrence. All the results above indicated Nb2C@PDA-R837@RBC NPs as a potential RBC camouflaged nanoplatform for the combination of effective PTT and immune therapy towards tumor treatment.


Asunto(s)
Hipertermia Inducida , Nanopartículas , Neoplasias , Línea Celular Tumoral , Rayos Infrarrojos , Niobio , Fototerapia
20.
Org Lett ; 23(18): 7156-7160, 2021 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-34468157

RESUMEN

A new, simple, yet easily accessible, (1-selenocyanatoethyl)benzene has been designed and applied as a SeCN group transfer reagent for selenocyanation of aliphatic C(sp3)-H bonds for the first time. This protocol is featured with mild reaction conditions and wide substrate scope. Control experiments reveal that a radical-group transfer mechanism might be involved.

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