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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 324: 125013, 2025 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-39186875

RESUMO

As a reactive sulfur species, sulfur dioxide (SO2) and its derivatives play crucial role in various physiological processes, which can maintain redox homeostasis at normal levels and lead to the occurrence of many diseases at abnormal levels. So, the development of a suitable fluorescent probe is a crucial step in advancing our understanding of the role of SO2 derivatives in living organisms. Herein, we developed a near-infrared fluorescent probe (SP) based on the ICT mechanism to monitor SO2 derivatives in living organisms in a ratiometric manner. The probe SP exhibited excellent selectivity, good sensitivity, fast response rate (within 50 s), and low detection limit (1.79 µM). In addition, the cell experiment results suggested that the SP has been successfully employed for the real-time monitoring of endogenous and exogenous SO2 derivatives with negligible cytotoxicity. Moreover, SP was effective in detecting SO2 derivatives in mice.


Assuntos
Corantes Fluorescentes , Dióxido de Enxofre , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Dióxido de Enxofre/análise , Animais , Camundongos , Humanos , Limite de Detecção , Espectrometria de Fluorescência , Imagem Óptica , Células HeLa
2.
J Am Chem Soc ; 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39353154

RESUMO

Solar-driven carbon dioxide (CO2) reduction into C2+ products such as ethylene represents an enticing route toward achieving carbon neutrality. However, due to sluggish electron transfer and intricate C-C coupling, it remains challenging to achieve highly efficient and selective ethylene production from CO2 and H2O beyond capitalizing on Cu-based catalysts. Herein, we report a judicious design to attain asymmetric C-C coupling through interfacial defect-rendered tandem catalytic centers within a sulfur-vacancy-rich MoSx/Fe2O3 photocatalyst sheet, enabling a robust CO2 photoreduction to ethylene without the need for copper, noble metals, and sacrificial agents. Specifically, interfacial S vacancies induce adjacent under-coordinated S atoms to form Fe-S bonds as a rapid electron-transfer pathway for yielding a Z-scheme band alignment. Moreover, these S vacancies further modulate the strong coupling interaction to generate a nitrogenase-analogous Mo-Fe heteronuclear unit and induce the upward shift of the d-band center. This bioinspired interface structure effectively suppresses electrostatic repulsion between neighboring *CO and *COH intermediates via d-p hybridization, ultimately facilitating an asymmetric C-C coupling to achieve a remarkable solar-to-chemical efficiency of 0.565% with a superior selectivity of 84.9% for ethylene production. Further strengthened by MoSx/WO3, our design unveils a promising platform for optimizing interfacial electron transfer and offers a new option for C2+ synthesis from CO2 and H2O using copper-free and noble metal-free catalysts.

3.
BMC Surg ; 24(1): 277, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39354471

RESUMO

OBJECTIVE: Lymphaticovenular anastomosis (LVA) is increasingly utilized in the treatment of lymphedema. This study aims to assess the efficacy and safety of the "Overlapping" LVA technique, which addresses the size mismatch between lymphatic and venous vessels in lymphedema treatment. METHODS: Between August 2022 and April 2023, seventeen patients diagnosed with lymphedema were enrolled in this study. The severity of lymphedema in these patients was classified according to the International Society of Lymphology (ISL) staging system.All patient underwent LVA procedures, anastomosis techniques including the Overlapping, end-to-end and octopus anastomosis. The techniques of anastomosis, anastomosis time, patency rate, and volume of limb lymphedema were evaluated. RESULTS: Our study enrolled 17 lymphedema patients who underwent the LVA procedure. All patients showed significant postoperative improvement in limb edema. The mean drainage volume was 472.29 ml. The Overlapping technique demonstrated a 100% success rate as assessed by clinical observation and intraoperative Indocyanine Green (ICG) lymphography. The average anastomosis time was 5.3 min, reducing operative time compared to traditional methods. CONCLUSIONS: These findings suggest that the Overlapping technique could serve as a valuable addition to the current LVA technique. This Overlapping anastomosis technique provides a wide range of applications for lymphatic anastomosis treatment and prevention of lymphedema.


Assuntos
Anastomose Cirúrgica , Vasos Linfáticos , Linfedema , Microcirurgia , Humanos , Anastomose Cirúrgica/métodos , Linfedema/cirurgia , Vasos Linfáticos/cirurgia , Pessoa de Meia-Idade , Feminino , Masculino , Adulto , Idoso , Microcirurgia/métodos , Resultado do Tratamento , Veias/cirurgia , Duração da Cirurgia , Linfografia/métodos , Estudos Retrospectivos
4.
Elife ; 132024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39365738

RESUMO

Artificially sweetened beverages containing noncaloric monosaccharides were suggested as healthier alternatives to sugar-sweetened beverages. Nevertheless, the potential detrimental effects of these noncaloric monosaccharides on blood vessel function remain inadequately understood. We have established a zebrafish model that exhibits significant excessive angiogenesis induced by high glucose, resembling the hyperangiogenic characteristics observed in proliferative diabetic retinopathy (PDR). Utilizing this model, we observed that glucose and noncaloric monosaccharides could induce excessive formation of blood vessels, especially intersegmental vessels (ISVs). The excessively branched vessels were observed to be formed by ectopic activation of quiescent endothelial cells (ECs) into tip cells. Single-cell transcriptomic sequencing analysis of the ECs in the embryos exposed to high glucose revealed an augmented ratio of capillary ECs, proliferating ECs, and a series of upregulated proangiogenic genes. Further analysis and experiments validated that reduced foxo1a mediated the excessive angiogenesis induced by monosaccharides via upregulating the expression of marcksl1a. This study has provided new evidence showing the negative effects of noncaloric monosaccharides on the vascular system and the underlying mechanisms.


Consuming too much sugar can damage blood vessels and contribute to diseases like diabetes and heart disease. Artificial sweeteners have been suggested as a healthier alternative, and are now included in many products like sodas and baked goods. However, some studies have suggested that people who consume large amounts of artificial sweeteners also have an increased risk of cardiovascular disease. Others suggest individuals may also experience spikes in blood sugar levels similar to those observed in people with diabetes. Yet few studies have examined how artificial sweeteners affect the network of vessels that transport blood and other substances around the body. To investigate this question, Wang, Zhao, Xu, et al. studied zebrafish embryos which had been exposed to sugar and a type of artificial sweetener known as non-caloric monosaccharides. Various imaging tools revealed that high levels of sugar caused the embryos to produce more new blood vessels via a process called angiogenesis. This excessive growth of blood vessels has previously been linked to diabetic complications, including cardiovascular disease. Wang, Zhao, Xu, et al. found that zebrafish embryos exposed to several different non-caloric monosaccharides developed similar blood vessel problems. All the sweeteners tested caused immature cells lining the blood vessels to develop into active tip cells that promote angiogenesis. This led to more new blood vessels forming that branch off already existing veins and arteries. These findings suggest that artificial sweeteners may cause the same kind of damage to blood vessels as sugar. This may explain why people who consume a lot of artificial sweeteners are at risk of developing heart disease and high blood sugar levels. Future studies could help scientists learn more about how genetics or other factors affect the health impact of sugars and artificial sweeteners. This may lead to a greater understanding of the long-term health effects of artificially sweetened foods.


Assuntos
Proteína Forkhead Box O1 , Monossacarídeos , Neovascularização Fisiológica , Peixe-Zebra , Animais , Neovascularização Fisiológica/efeitos dos fármacos , Monossacarídeos/metabolismo , Proteína Forkhead Box O1/metabolismo , Proteína Forkhead Box O1/genética , Células Endoteliais/metabolismo , Células Endoteliais/efeitos dos fármacos , Glucose/metabolismo , Glucose/farmacologia , Proteínas de Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Transdução de Sinais , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Angiogênese
5.
Cancer Immunol Immunother ; 73(12): 257, 2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-39367943

RESUMO

Neoadjuvant chemoimmunotherapy (NACI) has significant implications for the treatment of esophageal cancer. However, its clinical efficacy varies considerably among patients, necessitating further investigation into the underlying mechanisms. The rapid advancement of single-cell RNA sequencing (scRNA-seq) technology facilitates the analysis of patient heterogeneity at the cellular level, particularly regarding treatment outcomes. In this study, we first analyzed scRNA-seq data of esophageal squamous cell carcinoma (ESCC) following NACI, obtained from the Gene Expression Omnibus (GEO) database. After performing dimensionality reduction, clustering, and annotation on the scRNA-seq data, we employed CellChat to investigate differences in cell-cell communication among samples from distinct efficacy groups. The results indicated that macrophages in the non-responder exhibited stronger cell communication intensity compared to those in responders, with SPP1 and GALECTIN signals showing the most significant differences between the two groups. This finding underscores the crucial role of macrophages in the efficacy of NACI. Subsequently, reclustering of macrophages revealed that Mac-SPP1 may be primarily responsible for treatment resistance, while Mac-C1QC appears to promote T cell activation. Finally, we conducted transcriptome sequencing on ESCC tissues obtained from 32 patients who underwent surgery following NACI. Utilizing CIBERSORT, CIBERSORTx, and WGCNA, we analyzed the heterogeneity of tumor microenvironment among different efficacy groups and validated the correlation between SPP1+ macrophages and resistance to NACI in ESCC using publicly available transcriptome sequencing datasets. These findings suggest that SPP1+ macrophages may represent a key factor contributing to resistance against NACI in ESCC.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Imunoterapia , Macrófagos , Terapia Neoadjuvante , RNA-Seq , Análise de Célula Única , Humanos , Terapia Neoadjuvante/métodos , Carcinoma de Células Escamosas do Esôfago/terapia , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/imunologia , Neoplasias Esofágicas/terapia , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Análise de Célula Única/métodos , Resistencia a Medicamentos Antineoplásicos/genética , Imunoterapia/métodos , Osteopontina/genética , Osteopontina/metabolismo , Microambiente Tumoral/imunologia , Masculino , Feminino , Biomarcadores Tumorais/genética , Análise da Expressão Gênica de Célula Única
6.
Adv Healthc Mater ; : e2400509, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39352052

RESUMO

Despite great promise, application of mRNA therapeutics in the lung has proven challenging. Many groups have reported success instilling liquid mRNA formulations in animal models, but direct intratracheal administration of large liquid quantities to the human lung presents significant safety and distribution concerns. To accomplish safe and effective mRNA delivery to the lung, formulations must be prepared for dosing via inhalation. An inhaled mRNA delivery system for the lung must be both robust enough to survive inhalation conditions and potent enough to deliver mRNA upon reaching the lung. In this work dry powder lipid nanoparticle formulations are developed, using spray-freeze-drying, to produce stable, biologically active, inhalable dry powders for mRNA delivery. The final powders have suitable aerosolization properties, with mean mass aerodynamic diameter (MMAD) of 3-4 microns, and fine particle fraction (FPF) ≈40%, allowing for efficient mRNA delivery to the deep lung following inhalation. Importantly, the formulations developed here are suitable for use with different ionizable lipids. Four different ionizable lipid-based formulations are evaluated as powders, and all exhibit in vivo pulmonary mRNA delivery equal to that of instilled liquid formulations. These results lay promising groundwork for the eventual development of an inhalable mRNA dry powder therapeutic.

7.
Cell Signal ; 124: 111445, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39366532

RESUMO

Aberrant splicing is a significant contributor to gene expression abnormalities in cancer. SNRPB2, a component of U2 small nuclear ribonucleoprotein particles (snRNPs), contributes to the assembly of the spliceosome, the molecular machinery responsible for splicing. To date, few studies have investigated the role of SNRPB2 in tumorigenesis. We examined data sourced from various public databases, such as The Cancer Genome Atlas(TCGA), the Clinical Proteomic Tumor Analysis Consortium(CPTAC), and Gene Expression Omnibus(GEO). Our investigation included gene expression, genomic and epigenomic scrutiny, gene set enrichment assessment(GSEA), and immune cell infiltration evaluation. Furthermore, we performed empirical validation to ascertain the impact of SNRPB2 suppression on the proliferation and migration of liver cancer cells. Analysis of gene expression revealed widespread upregulation of SNRPB2 across a spectrum of cancer types, with heightened levels of SNRPB2 expression in numerous tumors linked to unfavorable prognosis. Genomic and epigenomic assessments revealed connections between SNRPB2 expression and variations in SNRPB2 copy number, DNA methylation patterns, and RNA modifications. Through gene set enrichment analysis, the involvement of SNRPB2 in vital biological processes and pathways related to cancer was identified. Furthermore, scrutiny of immune cell infiltration suggested a potential relationship between SNRPB2 and the tumor microenvironment, which was reinforced by multiple single-cell sequencing profiles. Subsequent experimental validation revealed that silencing SNRPB2 effectively impeded the proliferation and migration of liver cancer cells. Taken together, these findings underscore the prospective utility of SNRPB2 as a prognostic biomarker and a promising candidate for immunotherapy in cancer. It is necessary to engage in additional exploration into its underlying mechanisms and clinical treatment potential.

8.
Acta Biomater ; 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39368722

RESUMO

Oral biotherapeutics hold significant promise, but their lack of controllability and targeting poses a major challenge, particularly for intestinal bacterial biotherapeutics. In response, we have developed a nanoencapsulation approach that responds to the release of enzyme activity in the organism and activates the enzyme in situ, allowing for controlled colonization of microbes in the gut. The nano-coating comprises a two-layer structure: an inner layer of polydopamine with photothermal and adhesive properties, and an outer layer of gelatin-sodium carboxymethylcellulose, which is hydrolyzed by cellulases in the gut following photothermal interaction with dopamine. We have successfully achieved controlled colonization of a wide range of microorganisms. Furthermore, in a diabetes model, this approach has had a profound impact on regulating glucagon-like peptide-1 (GLP-1) production, ß-cell physiology, and promoting insulin secretion. This nanocoating is achieved by in situ activation of cellulase without the need for genetic or targeted molecular modification, representing a new paradigm and alternative strategy for microbial therapy. It not only enables precise and controlled colonization of probiotics but also demonstrates great potential for broader application in the field of oral biotherapy. STATEMENT OF SIGNIFICANCE: We have developed a nano-encapsulation method that triggers enzyme activity in response to enzymatic activity, resulting in the controlled release and adhesion of a wide range of microorganisms in the gut. The nano coating comprises two layers: an inner layer of polydopamine with photothermal and adhesion properties, and an outer layer of a gelatin-sodium carboxymethylcellulose polymer, which can be hydrolyzed by cellulases in the intestine. Additionally, this method allows for the preparation of various microbial coatings. This approach holds significant promise for regulating GLP-1 production, the physiological function of pancreatic ß-cells, and promoting insulin secretion in diabetes models.

9.
Sci Rep ; 14(1): 23673, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39390077

RESUMO

To improve the dielectric performance of the anodic alumina film used in aluminum electrolytic capacitors, this study comparatively investigated the microstructure and dielectric properties of anodic aluminum oxide obtained through micro-arc oxidation (MAO) and conventional anodic oxidation (CAO). It is found that from the perspective of microstructure, the internal structure of the MAO treated oxide film has more and larger pores than that of CAO. This was attributed to the generation and overflow of numerous oxygen bubbles from within the oxide film at the locations where plasma sparks occurred during the process, thus forming larger pores. Regarding dielectric properties, the leakage current of the oxide film after MAO treatment was significantly reduced compared to CAO, with reductions of 58%, 56%, 64%, and 74% for the tested electrolytes Y1-Y4, respectively.

10.
Anal Chem ; 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39399894

RESUMO

Genetically sequencing patient-derived organoids (PDOs) at the single-cell level has emerged as a promising method to infer cell-level heterogeneity of original organs and improve cancer precision medicine. Unfortunately, because of the limited starting quantity and uncontrolled establishing process of PDOs, the existing single-cell sequencing technologies, either manual-operation-based or microfluid-based, are inefficient in processing PDOs originating from clinical tissue samples. To address such issues, this study presents a microfluidic chip-based automatic system for sequencing organoids at the single-cell level, named as MASSO. By performing all required procedures, including PDO establishment/culturing/digesting and single-cell isolation/lysis/whole-genome amplification, in a single microfluidic chip, the possible loss of precious PDO is avoided, and the high quality of on-chip whole-genome amplification of a single PDO cell is ensured. By automating the entire operation process, possible human error is eliminated, and the data repeatability is improved, therefore bridging the technical gap between laboratorial proof-of-concept studies and clinical practices. After characterizing the organoid single-cell whole-genome amplification chip (named as OSA-Chip) and the MASSO, the first successful attempt, to the best of our knowledge, on whole-genome sequencing lung cancer PDO at the single-cell level was performed by MASSO. The results reveal that the MASSO is capable of not only identifying common cancer-related mutations but also discovering specific mutations that affect drug responses, therefore laying the technical foundation for efficiently understanding the cell-level heterogeneities of PDOs and corresponding original organs.

11.
Adv Sci (Weinh) ; : e2405965, 2024 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-39400530

RESUMO

Aminocyanines incorporating Cy7 and Cy7.5 moieties function as molecular jackhammers (MJH) through vibronic-driven action (VDA). This mechanism, which couples molecular vibrational and electronic modes, results in picosecond-scale concerted stretching of the entire molecule. When cell-associated and activated by near-infrared light, MJH mechanically disrupts cell membranes, causing rapid necrotic cell death. Unlike photodynamic and photothermal therapies, the ultrafast vibrational action of MJH is unhindered by high concentrations of reactive oxygen species scavengers and induces only a minimal temperature increase. Here, the efficient synthesis of a library of MJH is described using a practical approach to access a key intermediate and facilitating the preparation of various Cy7 and Cy7.5 MJH with diverse side chains in moderate to high yields. Photophysical characterization reveals that structural modifications significantly affect molar extinction coefficients and quantum yields while maintaining desirable absorption and emission wavelengths. The most promising compounds, featuring dimethylaminoethyl and dimethylcarbamoyl substitutions, demonstrate up to sevenfold improvement in phototherapeutic index compared to Cy7.5 amine across multiple cancer cell lines. This synthetic strategy provides a valuable platform for developing potent, light-activated therapeutic agents for cancer treatment, with potentially broad applicability across various cancer types.

12.
NPJ Precis Oncol ; 8(1): 229, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39384982

RESUMO

The incidence of multiple primary lung cancer (MPLC) is increasing, with some of our surgical patients exhibiting numerous lesions. We defined lung cancer with five or more primary lesions as super MPLCs. Elucidating the genomic characteristics of this special MPLC subtype can help reduce disease burden and understand tumor evolution. In our cohort of synchronous super early-stage MPLCs (PUMCH-ssesMPLC), whole-exome sequencing on 130 resected malignant specimens from 18 patients provided comprehensive super-MPLC genomic landscapes. Mutations are enriched in PI3k-Akt and MAPK pathways. Their BRAF mutation frequency (31.5%) is significantly higher than MPLC with fewer lesions and early-stage single-lesion cancer, while EGFR mutations are significantly fewer (13.8%). As lesion counts increase, BRAF mutations gradually become dominant. Also, invasive lesions more tend to have classic super-MPLC mutation patterns. High-frequency BRAF mutations, especially Class II, and low-frequency EGFR mutations could be a reason for the limited effectiveness of targeted therapy in super-MPLC patients.

13.
Signal Transduct Target Ther ; 9(1): 274, 2024 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-39420203

RESUMO

Immunotherapy has made significant strides in cancer treatment, particularly through immune checkpoint blockade (ICB), which has shown notable clinical benefits across various tumor types. Despite the transformative impact of ICB treatment in cancer therapy, only a minority of patients exhibit a positive response to it. In patients with solid tumors, those who respond well to ICB treatment typically demonstrate an active immune profile referred to as the "hot" (immune-inflamed) phenotype. On the other hand, non-responsive patients may exhibit a distinct "cold" (immune-desert) phenotype, differing from the features of "hot" tumors. Additionally, there is a more nuanced "excluded" immune phenotype, positioned between the "cold" and "hot" categories, known as the immune "excluded" type. Effective differentiation between "cold" and "hot" tumors, and understanding tumor intrinsic factors, immune characteristics, TME, and external factors are critical for predicting tumor response and treatment results. It is widely accepted that ICB therapy exerts a more profound effect on "hot" tumors, with limited efficacy against "cold" or "altered" tumors, necessitating combinations with other therapeutic modalities to enhance immune cell infiltration into tumor tissue and convert "cold" or "altered" tumors into "hot" ones. Therefore, aligning with the traits of "cold" and "hot" tumors, this review systematically delineates the respective immune characteristics, influencing factors, and extensively discusses varied treatment approaches and drug targets based on "cold" and "hot" tumors to assess clinical efficacy.


Assuntos
Neoplasias , Humanos , Neoplasias/imunologia , Neoplasias/genética , Neoplasias/tratamento farmacológico , Neoplasias/terapia , Microambiente Tumoral/imunologia , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/genética , Imunoterapia , Inibidores de Checkpoint Imunológico/uso terapêutico , Terapia de Alvo Molecular
14.
Adv Mater ; : e2412210, 2024 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-39420657

RESUMO

Reconfigurable devices with field-effect transistor features and neuromorphic behaviors are promising for enhancing data processing capability and reducing power consumption in next-generation semiconductor platforms. However, commonly used 2D materials for reconfigurable devices require additional modulation terminals and suffer from complex and stringent operating rules to obtain specific functionalities. Here, a p-type disordered tellurium oxide is introduced that realizes dual-mode reconfigurability as a logic transistor and a neuromorphic device. Due to the disordered film surface, the enhanced adsorption of oxygen molecules and laser-induced desorption concurrently regulate the carrier concentration in the channel. The device exhibits high-performance p-type characteristics with a field-effect hole mobility of 10.02 cm2 V-1 s-1 and an Ion/Ioff ratio exceeding 106 in the transistor mode. As a neuromorphic device, the vision system exhibits biomimetic bee vision, explicitly responding to the blue-to-ultraviolet light. Finally, in-sensor denoising and invisible image recognition in static and dynamic scenarios are achieved.

15.
Adv Mater ; : e2410952, 2024 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-39420661

RESUMO

Brain-like intelligence is ushering humanity into an era of the Internet of Perceptions (IoP), where the vast amounts of data generated by numerous sensing nodes pose significant challenges to transmission bandwidth and computing hardware. A recently proposed near-sensor computing architecture offers an effective solution to reduce data processing delays and energy consumption. However, a pressing need remains for innovative hardware with multifunctional near-sensor image processing capabilities. In this work, Mott material (vanadium dioxide)-based photothermoelectric near-infrared photodetectors are developed that exhibit electrode-dependent and tunable super-linear photoresponse (exponent α > 33) with ultralow modulation bias. These devices demonstrate an opto-thermo-electro-coupled phase transition, resulting in a large photocurrent on/off ratio (>105), high responsivity (≈500 A W-1), and well detectivity (≈3.9 × 1012 Jones), all while maintaining rapid response speeds (τr = 2 µs and τd = 5 µs) under the bias of 1 V. This electrode-dependent super-linear response is found to arise from the electron doping effect determined by the polarity of the Seebeck coefficient. Furthermore, the work showcases intensity-selective near-sensor processing and night vision pattern reorganization, even with noisy inputs. This work paves the way for developing near-sensor devices with potential applications in medical image preprocessing, flexible electronics, and intelligent edge sensing.

16.
Chem Commun (Camb) ; 60(84): 12217-12220, 2024 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-39356229

RESUMO

Herein, a pyrolysis-induced precursor transformation strategy has been proposed. Using pre-synthesized PDA-M as a precursor, the production of transition metal single atom catalysts (SACs) has been achieved, with compositional flexibility at high metal loadings. In particular, the Ni SAC sample has shown promising CO selectivity when evaluated for the electrochemical CO2 reduction reaction, reaching 29.8 mA cm-2 CO partial current density and 90.3% CO faradaic efficiency at -1.05 V vs. RHE.

17.
Nat Commun ; 15(1): 8947, 2024 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-39414855

RESUMO

As a transdermal drug delivery method, microneedles offer minimal invasiveness, painlessness, and precise in-situ treatment. However, current microneedles rely on passive diffusion, leading to uncontrollable drug penetration. To overcome this, we developed a pneumatic microneedle patch that uses live Enterobacter aerogenes as microengines to actively control drug delivery. These microbes generate gas, driving drugs into deeper tissues, with adjustable glucose concentration allowing precise control over the process. Our results showed that this microorganism-powered system increases drug delivery depth by over 200%, reaching up to 1000 µm below the skin. In a psoriasis animal model, the technology effectively delivered calcitriol into subcutaneous tissues, offering rapid symptom relief. This innovation addresses the limitations of conventional microneedles, enhancing drug efficiency, transdermal permeability, and introducing a creative paradigm for on-demand controlled drug delivery.


Assuntos
Administração Cutânea , Sistemas de Liberação de Medicamentos , Agulhas , Sistemas de Liberação de Medicamentos/instrumentação , Sistemas de Liberação de Medicamentos/métodos , Animais , Enterobacter aerogenes/efeitos dos fármacos , Pele/metabolismo , Pele/microbiologia , Microinjeções/instrumentação , Microinjeções/métodos , Camundongos , Humanos , Modelos Animais de Doenças , Absorção Cutânea
18.
Sci Rep ; 14(1): 22169, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39333291

RESUMO

Polyamide 6 (PA6) films with significant α relaxation process was selected as the model system. The creep behavior and rheological mechanism during deformation in the amorphous regions of semi-crystalline polymers are systematically investigated by carrying out creep experiments. Based on the quasi point defect (QPD) theory, the complete physical process of PA6 film creep behavior from elasticity to viscoelasticity and viscoplasticity was analyzed and modeled from the perspective of structural heterogeneity. The results demonstrate that the creep deformation of PA6 film is a typical thermo-mechanical coupling and nonlinear mechanics process, and potential creep mechanisms corresponds to stress-induced local shear deformation enhancement and thermal activation-induced particle flow diffusion. The elastic-plastic transition involved in the creep deformation process of semi-crystalline polymer originates from the activation of quasi-point defective sites in the amorphous region, the expansion of sheared micro-domains and irreversible fusion. The generalized fractional Kelvin (GFK) model is proposed, and the physical meaning of parameters is explained by combining the quasi point defect theory and creep delay spectrum(L(τ)). Finally, the effectiveness of the GFK model and the QPD theory in studying the deformation behavior of PA6 films was validated by comparing experimental data with theoretical results, which theoretically reveals the structural evolution of PA6 film during creep process.

19.
ACS Nano ; 18(39): 27042-27054, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39298299

RESUMO

Chemodynamic therapy (CDT) can induce cancer cell death through hydroxyl radicals (·OH) generated from Fenton or Fenton-like reactions. Compared with traditional therapies, CDT effectively overcomes inevitable drug resistance and exhibits low side effects. However, clinical application still faces challenges, primarily due to insufficient ·OH generation and the short-lifetime of ·OH in vivo. To address these challenges, we developed a peroxynitrite (ONOO-)-based CDT nanodrug (DOX@PMOF) composed of MOF-199, NO donor (PArg), and nicotinamide adenine dinucleotide phosphate oxidase 4 (NOX4) activator (doxorubicin, DOX). In DOX@PMOF, MOF-199 serves as both a carrier for loading DOX and a source of Cu+ for triggering CDT. Upon uptake by cancer cells, the high concentration of glutathione (GSH) reduces MOF-199 to Cu+, which then reacts with H2O2 to generate ·OH. Moreover, the released DOX upregulates NOX4 expression, leading to the elevated H2O2 level and thereby promoting a high-efficiency Fenton-like reaction for sufficient ·OH generation. Subsequently, PArg generates abundant NO in response to the tumor microenvironment, leading to a cascade of NO and ·OH for the in situ synthesis of ONOO-. ONOO- is more toxic and has a longer lifetime and diffusion distance than ·OH, resulting in a more effective CDT treatment. To further enhance the in vivo therapeutic effect, we coated DOX@PMOF with a homologous cell membrane to form an active tumor-targeting nanodrug (DOX@MPMOF), which has demonstrated the ability to effectively inhibit tumor growth and metastasis while exhibiting good biosafety.


Assuntos
Doxorrubicina , Ácido Peroxinitroso , Microambiente Tumoral , Ácido Peroxinitroso/metabolismo , Ácido Peroxinitroso/química , Microambiente Tumoral/efeitos dos fármacos , Doxorrubicina/farmacologia , Doxorrubicina/química , Humanos , Animais , Camundongos , Camundongos Endogâmicos BALB C , Linhagem Celular Tumoral , Antibióticos Antineoplásicos/farmacologia , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/síntese química , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/farmacologia , Estruturas Metalorgânicas/síntese química , Feminino , Nanopartículas/química
20.
Nat Commun ; 15(1): 8298, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39333067

RESUMO

Wearable visual bionic devices, fueled by advancements in artificial intelligence, are making remarkable progress. However, traditional silicon vision chips often grapple with high energy losses and challenges in emulating complex biological behaviors. In this study, we constructed a van der Waals P3HT/GaAs nanowires P-N junction by carefully directing the arrangement of organic molecules. Combined with a Schottky junction, this facilitated multi-faceted birdlike visual enhancement, including broadband non-volatile storage, low-light perception, and a near-zero power consumption operating mode in both individual devices and 5 × 5 arrays on arbitrary substrates. Specifically, we realized over 5 bits of in-memory sensing and computing with both negative and positive photoconductivity. When paired with two imaging modes (visible and UV), our reservoir computing system demonstrated up to 94% accuracy for color recognition. It achieved motion and UV grayscale information extraction (displayed with sunscreen), leading to fusion visual imaging. This work provides a promising co-design of material and device for a broadband and highly biomimetic optoelectronic neuromorphic system.

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