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1.
Molecules ; 29(9)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38731472

RESUMO

Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by the accumulation of amyloid beta (Aß) plaques in the brain. Aß1-42 is the main component of Aß plaque, which is toxic to neuronal cells. Si nanowires (Si NWs) have the advantages of small particle size, high specific surface area, and good biocompatibility, and have potential application prospects in suppressing Aß aggregation. In this study, we employed the vapor-liquid-solid (VLS) growth mechanism to grow Si NWs using Au nanoparticles as catalysts in a plasma-enhanced chemical vapor deposition (PECVD) system. Subsequently, these Si NWs were transferred to a phosphoric acid buffer solution (PBS). We found that Si NWs significantly reduced cell death in PC12 cells (rat adrenal pheochromocytoma cells) induced by Aß1-42 oligomers via double staining with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and fluorescein diacetate/propyl iodide (FDA/PI). Most importantly, pre-incubated Si NWs largely prevented Aß1-42 oligomer-induced PC12 cell death, suggesting that Si NWs exerts an anti-Aß neuroprotective effect by inhibiting Aß aggregation. The analysis of Fourier Transform Infrared (FTIR) results demonstrates that Si NWs reduce the toxicity of fibrils and oligomers by intervening in the formation of ß-sheet structures, thereby protecting the viability of nerve cells. Our findings suggest that Si NWs may be a potential therapeutic agent for AD by protecting neuronal cells from the toxicity of Aß1-42.


Assuntos
Peptídeos beta-Amiloides , Nanofios , Silício , Peptídeos beta-Amiloides/toxicidade , Peptídeos beta-Amiloides/metabolismo , Peptídeos beta-Amiloides/antagonistas & inibidores , Nanofios/química , Animais , Células PC12 , Ratos , Silício/química , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/toxicidade , Fragmentos de Peptídeos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/química , Agregados Proteicos/efeitos dos fármacos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo
2.
ACS Appl Mater Interfaces ; 16(19): 24410-24420, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38709954

RESUMO

Sonophotodynamic antimicrobial therapy (SPDAT) is recognized as a highly efficient biomedical treatment option, known for its versatility and remarkable healing outcomes. Nevertheless, there is a scarcity of sonophotosensitizers that demonstrate both low cytotoxicity and exceptional antibacterial effectiveness in clinical applications. In this paper, a novel ZnO nanowires (NWs)@TiO2-xNy core-sheath composite was developed, which integrates the piezoelectric effect and heterojunction to build dual built-in electric fields. Remarkably, it showed superb antibacterial effectiveness (achieving 95% within 60 min against S. aureus and ∼100% within 40 min against E. coli, respectively) when exposed to visible light and ultrasound. Due to the continuous interference caused by light and ultrasound, the material's electrostatic equilibrium gets disrupted. The modification in electrical properties facilitates the composite's ability to attract bacterial cells through electrostatic forces. Moreover, Zn-O-Ti and Zn-N-Ti bonds formed at the interface of ZnO NWs@TiO2-xNy, further enhancing the dual internal electric fields to accelerate the excited carrier separation to generate more reactive oxygen species (ROS), and thereby boosting the antimicrobial performance. In addition, the TiO2 layer limited Zn2+ dissolution into solution, leading to good biocompatibility and low cytotoxicity. Lastly, we suggest a mechanistic model to offer practical direction for the future development of antibacterial agents that are both low in toxicity and high in efficacy. In comparison to the traditional photodynamic therapy systems, ZnO NWs@TiO2-xNy composites exhibit super piezo-photocatalytic antibacterial activity with low toxicity, which shows great potential for clinical application as an antibacterial nanomaterial.


Assuntos
Antibacterianos , Escherichia coli , Nanofios , Staphylococcus aureus , Titânio , Óxido de Zinco , Titânio/química , Titânio/farmacologia , Titânio/efeitos da radiação , Óxido de Zinco/química , Óxido de Zinco/farmacologia , Antibacterianos/química , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Nanofios/química , Catálise , Espécies Reativas de Oxigênio/metabolismo , Testes de Sensibilidade Microbiana , Humanos , Luz , Camundongos , Animais
3.
Nat Commun ; 15(1): 3902, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724527

RESUMO

Radiation-induced in situ tumor vaccination alone is very weak and insufficient to elicit robust antitumor immune responses. In this work, we address this issue by developing chiral vidarabine monophosphate-gadolinium nanowires (aAGd-NWs) through coordination-driven self-assembly. We elucidate the mechanism of aAGd-NW assembly and characterize their distinct features, which include a negative surface charge, ultrafine topography, and right-handed chirality. Additionally, aAGd-NWs not only enhance X-ray deposition but also inhibit DNA repair, thereby enhancing radiation-induced in situ vaccination. Consequently, the in situ vaccination induced by aAGd-NWs sensitizes radiation enhances CD8+ T-cell-dependent antitumor immunity and synergistically potentiates the efficacy immune checkpoint blockade therapies against both primary and metastatic tumors. The well-established aAGd-NWs exhibit exceptional therapeutic capacity and biocompatibility, offering a promising avenue for the development of radioimmunotherapy approaches.


Assuntos
Nanofios , Polímeros , Nanofios/química , Animais , Camundongos , Polímeros/química , Linhagem Celular Tumoral , Gadolínio/química , Gadolínio/farmacologia , Camundongos Endogâmicos C57BL , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Vacinas Anticâncer/imunologia , Feminino , Humanos , Vacinação/métodos , Neoplasias/imunologia
4.
Anal Chem ; 96(19): 7470-7478, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38696229

RESUMO

MicroRNAs (miRNAs) are endogenous and noncoding single-stranded RNA molecules with a length of approximately 18-25 nucleotides, which play an undeniable role in early cancer screening. Therefore, it is very important to develop an ultrasensitive and highly specific method for detecting miRNAs. Here, we present a bottom-up assembly approach for modifying glass microtubes with silica nanowires (SiNWs) and develop a label-free sensing platform for miRNA-21 detection. The three-dimensional (3D) networks formed by SiNWs make them abundant and highly accessible sites for binding with peptide nucleic acid (PNA). As a receptor, PNA has no phosphate groups and exhibits an overall electrically neutral state, resulting in a relatively small repulsion between PNA and RNA, which can improve the hybridization efficiency. The SiNWs-filled glass microtube (SiNWs@GMT) sensor enables ultrasensitive, label-free detection of miRNA-21 with a detection limit as low as 1 aM at a detection range of 1 aM-100 nM. Noteworthy, the sensor can still detect miRNA-21 in the range of 102-108 fM in complex solutions containing 1000-fold homologous interference of miRNAs. The high anti-interference performance of the sensor enables it to specifically recognize target miRNA-21 in the presence of other miRNAs and distinguish 1-, 3-mismatch nucleotide sequences. Significantly, the sensor platform is able to detect miRNA-21 in the lysate of breast cancer cell lines (e.g., MCF-7 cells and MDA-MB-231 cells), indicating that it has good potential in the screening of early breast cancers.


Assuntos
Vidro , MicroRNAs , Nanofios , Ácidos Nucleicos Peptídicos , Dióxido de Silício , MicroRNAs/análise , Ácidos Nucleicos Peptídicos/química , Dióxido de Silício/química , Humanos , Nanofios/química , Vidro/química , Técnicas Biossensoriais/métodos , Limite de Detecção
5.
ACS Appl Mater Interfaces ; 16(19): 24341-24350, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38687629

RESUMO

Magnetic micro/nanorobots are promising platforms for targeted drug delivery, and their construction with soft and flexible features has received extensive attention for practical applications. Despite significant efforts in this field, facile fabrication of magnetic microrobots with flexible structures and versatility in targeted therapy remains a big challenge. Herein, we proposed a novel universal strategy to fabricate a biohybrid flexible sperm-like microrobot (BFSM) based on a Chlorella (Ch.) cell and artificial flagella, which showed great potential for targeted chemo-photothermal therapy for the first time. In this approach, microspherical Ch. cells were utilized to construct the microrobotic heads, which were intracellularly deposited with core-shell Pd@Au, extracellularly magnetized with Fe3O4, and further loaded with anticancer drug. The magnetic heads with excellent photothermal and chemotherapeutic capability were further assembled with flexible polypyrrole nanowires via biotin-streptavidin bonding to construct the BFSMs. Based on the exquisite head-to-tail structures, the BFSMs could be effectively propelled under precessing magnetic fields and move back and forth without a U-turn. Moreover, in vitro chemo-photothermal tests were conducted to verify their performance of targeted drug delivery toward localized HeLa cells. Due to this superior versatility and facile fabrication, the BFSMs demonstrated great potential for targeted anticancer therapy.


Assuntos
Terapia Fototérmica , Humanos , Células HeLa , Robótica , Sistemas de Liberação de Medicamentos , Antineoplásicos/química , Antineoplásicos/farmacologia , Doxorrubicina/química , Doxorrubicina/farmacologia , Polímeros/química , Nanofios/química , Ouro/química
6.
Sensors (Basel) ; 24(7)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38610372

RESUMO

The build-up of lactate in solid tumors stands as a crucial and early occurrence in malignancy development, and the concentration of lactate in the tumor microenvironment may be a more sensitive indicator for analyzing primary tumors. In this study, we designed a self-powered lactate sensor for the rapid analysis of tumor samples, utilizing the coupling between the piezoelectric effect and enzymatic reaction. This lactate sensor is fabricated using a ZnO nanowire array modified with lactate oxidase (LOx). The sensing process does not require an external power source or batteries. The device can directly output electric signals containing lactate concentration information when subjected to external forces. The lactate concentration detection upper limit of the sensor is at least 27 mM, with a limit of detection (LOD) of approximately 1.3 mM and a response time of around 10 s. This study innovatively applied self-powered technology to the in situ detection of the tumor microenvironment and used the results to estimate the growth period of the primary tumor. The availability of this application has been confirmed through biological experiments. Furthermore, the sensor data generated by the device offer valuable insights for evaluating the likelihood of remote tumor metastasis. This study may expand the research scope of self-powered technology in the field of medical diagnosis and offer a novel perspective on cancer diagnosis.


Assuntos
Nanofios , Neoplasias , Humanos , Ácido Láctico , Neoplasias/diagnóstico , Fontes de Energia Elétrica , Eletricidade , Microambiente Tumoral
7.
ACS Sens ; 9(4): 1896-1905, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38626402

RESUMO

With the escalating global awareness of air quality management, the need for continuous and reliable monitoring of toxic gases by using low-power operating systems has become increasingly important. One of which, semiconductor metal oxide gas sensors have received great attention due to their high/fast response and simple working mechanism. More specifically, self-heating metal oxide gas sensors, wherein direct thermal activation in the sensing material, have been sought for their low power-consuming characteristics. However, previous works have neglected to address the temperature distribution within the sensing material, resulting in inefficient gas response and prolonged response/recovery times, particularly due to the low-temperature regions. Here, we present a unique metal/metal oxide/metal (MMOM) nanowire architecture that conductively confines heat to the sensing material, achieving high uniformity in the temperature distribution. The proposed structure enables uniform thermal activation within the sensing material, allowing the sensor to efficiently react with the toxic gas. As a result, the proposed MMOM gas sensor showed significantly enhanced gas response (from 6.7 to 20.1% at 30 ppm), response time (from 195 to 17 s at 30 ppm), and limit of detection (∼1 ppm) when compared to those of conventional single-material structures upon exposure to carbon monoxide. Furthermore, the proposed work demonstrated low power consumption (2.36 mW) and high thermal durability (1500 on/off cycles), demonstrating its potential for practical applications in reliable and low-power operating gas sensor systems. These results propose a new paradigm for power-efficient and robust self-heating metal oxide gas sensors with potential implications for other fields requiring thermal engineering.


Assuntos
Gases , Nanofios , Óxidos , Nanofios/química , Gases/química , Gases/análise , Óxidos/química , Metais/química
8.
Sci Total Environ ; 925: 171763, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38494030

RESUMO

Microbial biofilms are behind microbiologically influenced corrosion (MIC). Sessile cells in biofilms are many times more concentrated volumetrically than planktonic cells in the bulk fluids, thus providing locally high concentrations of chemicals. More importantly, "electroactive" sessile cells in biofilms are capable of utilizing extracellularly supplied electrons (e.g., from elemental Fe) for intracellular reduction of an oxidant such as sulfate in energy metabolism. MIC directly caused by anaerobic biofilms is classified into two main types based on their mechanisms: extracellular electron transfer MIC (EET-MIC) and metabolite MIC (M-MIC). Sulfate-reducing bacteria (SRB) are notorious for their corrosivity. They can cause EET-MIC in carbon steel, but they can also secrete biogenic H2S to corrode other metals such as Cu directly via M-MIC. This study investigated the use of conductive magnetic nanowires as electron mediators to accelerate and thus identify EET-MIC of C1020 by Desulfovibrio vulgaris. The presence of 40 ppm (w/w) nanowires in ATCC 1249 culture medium at 37 °C resulted in 45 % higher weight loss and 57 % deeper corrosion pits after 7-day incubation. Electrochemical tests using linear polarization resistance and potentiodynamic polarization supported the weight loss data trend. These findings suggest that conductive magnetic nanowires can be employed to identify EET-MIC. The use of insoluble 2 µm long nanowires proved that the extracellular section of the electron transfer process is a bottleneck in SRB MIC of carbon steel.


Assuntos
Desulfovibrio vulgaris , Desulfovibrio , Nanofios , Humanos , Aço , Elétrons , Carbono/metabolismo , Biofilmes , Desulfovibrio/metabolismo , Corrosão , Sulfatos/metabolismo , Redução de Peso
9.
Talanta ; 272: 125772, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38367400

RESUMO

Hydrogen peroxide (H2O2) is a biomarker relevant for oxidative stress monitoring. Most chronic airway diseases are characterized by increased oxidative stress. To date, the main methods for the detection of this analyte are expensive and time-consuming laboratory techniques such as fluorometric and colorimetric assays. There is a growing interest in the development of electrochemical sensors for H2O2 detection due to their low cost, ease of use, sensitivity and rapid response. In this work, an electrochemical sensor based on gold nanowire arrays has been developed. Thanks to the catalytic activity of gold against hydrogen peroxide reduction and the high surface area of nanowires, this sensor allows the quantification of this analyte in a fast, efficient and selective way. The sensor was obtained by template electrodeposition and consists of gold nanowires about 5 µm high and with an average diameter of about 200 nm. The high active surface area of this electrode, about 7 times larger than a planar gold electrode, ensured a high sensitivity of the sensor (0.98 µA µM-1cm-2). The sensor allows the quantification of hydrogen peroxide in the range from 10 µM to 10 mM with a limit of detection of 3.2 µM. The sensor has excellent properties in terms of reproducibility, repeatability and selectivity. The sensor was validated by quantifying the hydrogen peroxide released by human airways A549 cells exposed or not to the pro-oxidant compound rotenone. The obtained results were validated by comparing them with those obtained by flow cytometry after staining the cells with the fluorescent superoxide-sensitive Mitosox Red probe giving a very good concordance.


Assuntos
Peróxido de Hidrogênio , Nanofios , Humanos , Peróxido de Hidrogênio/química , Nanofios/química , Ouro/química , Reprodutibilidade dos Testes , Técnicas Eletroquímicas/métodos , Células Epiteliais , Eletrodos
10.
ACS Sens ; 9(3): 1525-1532, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38377562

RESUMO

Peptides with distinct physiochemical properties and biocompatibility hold significant promise across diverse domains including antifouling biosensors. However, the stability of natural antifouling peptides in physiological conditions poses significant challenges to their viability for sustained practical applications. Herein, a unique antifouling peptide FFFGGGEKEKEKEK was designed and self-assembled to form peptide nanoparticles (PNPs), which possessed enhanced stability against enzymatic hydrolysis in biological fluids. The PNP-coated interfaces exhibited superior stability and antifouling properties in preventing adsorption of nonspecific materials, such as proteins and cells in biological samples. Moreover, a highly sensitive and ultralow fouling electrochemical biosensor was developed through the immobilization of the PNPs and specific aptamers onto the polyaniline nanowire-modified electrode, achieving the biomarker carcinoembryonic antigen detection in complex biofluids with reliable accuracy. This research not only addresses the challenge of the poor proteolytic resistance observed in natural peptides but also introduces a universal strategy for constructing ultralow fouling sensing devices.


Assuntos
Incrustação Biológica , Técnicas Biossensoriais , Nanopartículas , Nanofios , Incrustação Biológica/prevenção & controle , Peptídeos/química , Nanofios/química
11.
Anal Chim Acta ; 1292: 342233, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38309850

RESUMO

BACKGROUND: Label-free surface-enhanced Raman spectroscopy (SERS)-based metabolic profiling has great potential for early cancer diagnosis, but further advancements in analytical methods and clinical evidence studies are required for clinical applications. To improve the cancer diagnostic accuracy of label-free SERS spectral analysis of complex biological fluids, it is necessary to obtain specifically enhanced SERS signals of cancer-related metabolites present at low concentrations. RESULTS: This study presents a novel 3D SERS sensor, comprising a surface-carbonized silver nanowire (AgNW)-stacked filter membrane, alongside an optimized urine/methanol/chloroform extraction technique, which specifically changes the molecular adsorption and orientation of aromatic metabolites onto SERS substrates. By analyzing the pretreated urine samples on the surface-carbonized AgNW 3D SERS sensor, distinct and highly enhanced SERS peaks derived from semi-polar aromatic metabolites were observed for pancreatic cancer and prostate cancer samples compared with normal controls. Urine metabolite analysis using SERS fingerprinting successfully differentiated pancreatic cancer and prostate cancer groups from normal control group: normal control (n = 56), pancreatic cancer (n = 40), and prostate cancer (n = 39). SIGNIFICANCE AND NOVELTY: We confirmed the clinical feasibility of performing fingerprint analysis of urinary metabolites based on the surface-carbonized AgNW 3D SERS sensor and methanol/chloroform extraction for noninvasive cancer screening. This technology holds potential for large-scale screening owing to its high accuracy, and cost effective, simple and rapid detection method.


Assuntos
Nanopartículas Metálicas , Nanofios , Neoplasias Pancreáticas , Neoplasias da Próstata , Masculino , Humanos , Análise Espectral Raman/métodos , Detecção Precoce de Câncer , Prata/química , Clorofórmio , Metanol , Nanopartículas Metálicas/química
12.
ACS Sens ; 9(2): 979-987, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38299870

RESUMO

Through the capture of a target molecule at the metal surface with a highly confined electromagnetic field induced by surface plasmon, surface enhanced Raman spectroscopy (SERS) emerges as a spectral analysis technology with high sensitivity. However, accurate SERS identification of a gaseous molecule with low density and high velocity is still a challenge due to its difficulty in capture. In this work, a flexible paper-based plasmonic metal-organic framework (MOF) film consisting of Ag nanowires@ZIF-8 (AgNWs@ZIF-8) is fabricated for SERS detection of gaseous molecules. Benefiting from its micronanopores generated by the nanowire network and ZIF-8 shell, the effective capture of the gaseous molecule is achieved, and its SERS spectrum is obtained in this paper-based flexible plasmonic MOF nanowire film. With optimal structure parameters, spectra of gaseous 4-aminothiophenol, 4-mercaptophenol, and dithiohydroquinone demonstrate that this film has good SERS performance, which could maintain obvious Raman signals within 30 days during reproducible detection. To realize SERS identification of gaseous molecules, deep learning is performed based on the SERS spectra of the mixed gaseous analyte obtained in this flexible porous film. The results point out that an artificial neural network algorithm could identify gaseous aldehydes (gaseous biomarker of colorectal cancer) in simulated exhaled breath with high accuracy at 93.7%. The integration of the flexible paper-based film sensors with deep learning offers a promising new approach for noninvasive colorectal cancer screening. Our work explores SERS applications in gaseous analyte detection and has broad potential in clinical medicine, food safety, environmental monitoring, etc.


Assuntos
Aprendizado Profundo , Estruturas Metalorgânicas , Nanofios , Análise Espectral Raman , Aldeídos , Gases
13.
Anal Chim Acta ; 1288: 342148, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38220282

RESUMO

Long-term high blood glucose levels brings extremely detrimental effect on diabetic patients, such as blindness, renal failure, and cardiovascular diseases. Therefore, there is an urgent need to develop highly flexible and sensitive sensors for precisely non-invasive and continuous monitoring glucose levels. Herein, we present a highly flexible and sensitive wearable sensor for non-enzymatic electrochemical glucose analysis with vertically aligned mushroom-like gold nanowires (v-AuNWs) chemically grown on stainless steel wire sieve (SSWS) as integrated electrode. Owing to the unique nanostructures and excellent catalysis of the v-AuNWs, the as-fabricated glucose sensors exhibit superior flexibility and excellent electro-catalytic capability. In detail, these sensors display rapid response towards glucose within 5 s, and the sensor constructed with v-AuNWs for growth time of 15 min shows the highest sensitivity of 180.1 µA mM-1 cm-2 within a wide linear range of 6.5 × 10-4 mM-12.0 mM and the lowest detection limit of 0.65 µM (S/N = 3). It is noteworthy that due to the good ductility of the v-AuNWs and their strong contact with the SSWS substrate, these glucose sensors exhibit no obvious response variation after repeated bending for 100 times at bending angle of 180°. Additionally, the glucose sensors display superior anti-interfering capability as well as desirable repeatability. More importantly, these glucose sensors can be attached on human skin to determine sweat glucose reliably and analyze glucose concentration in human serum in vitro.


Assuntos
Técnicas Biossensoriais , Nanofios , Dispositivos Eletrônicos Vestíveis , Humanos , Nanofios/química , Ouro/química , Aço Inoxidável , Glucose/análise
14.
Redox Biol ; 70: 103055, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38290385

RESUMO

Nanozymes with superior antioxidant properties offer new hope for treating oxidative stress-related inflammatory skin diseases. However, lacking sufficient catalytic activity or having complex material designs limit the application of current metallic nanozymes in inflammatory skin diseases. Here, we report a simple and effective twin-defect platinum nanowires (Pt NWs) enzyme with multiple mimetic enzymes and broad-spectrum ROS scavenging capability for the treatment of inflammatory skin diseases in mice (including psoriasis and rosacea). Pt NWs with simultaneous superoxide dismutase, glutathione peroxidase and catalase mimetic enzyme properties exhibit cytoprotective effects against ROS-mediated damage at extremely low doses and significantly improve treatment outcomes in psoriasis- and rosacea-like mice. Meanwhile, these ultrasmall sizes of Pt NWs allow the nanomaterials to effectively penetrate the skin and do not produce significant biotoxicity. Therefore, Pt NWs have potential applications in treating diseases related to oxidative stress or inflammation.


Assuntos
Dermatite , Nanofios , Psoríase , Rosácea , Animais , Camundongos , Espécies Reativas de Oxigênio , Antioxidantes/farmacologia
15.
Adv Healthc Mater ; 13(7): e2302893, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38060694

RESUMO

Bandages for daily wounds are the most common medical supplies, but there are still ingrained defects in their appearance, comfort, functions, as well as environmental pollution. Here, novel bandages based on bacterial cellulose (BC) membrane for wound monitoring and advanced wound management are developed. The BC membrane is combined with silver nanowires (AgNWs) by using vacuum filtration method to achieve transparent, ultrathin (≈7 µm), breathable (389.98-547.79 g m-2  d-1 ), and sandwich-structured BC/AgNWs bandages with superior mechanical properties (108.45-202.35 MPa), antibacterial activities against Escherichia coli and Staphylococcus aureus, biocompatibility, and conductivity (9.8 × 103 -2.0 × 105  S m-1 ). Significantly, the BC/AgNWs bandage is used in the electrical stimulation (direct current, 600  microamperes for 1 h every other day) treatment of full-thickness skin defect in rats, which obviously promotes wound healing by increasing the secretion of vascular endothelial growth factor (VEGF). The BC bandage is used for monitoring wounds and achieve a high accuracy of 94.7% in classifying wound healing stages of hemostasis, inflammation, proliferation, and remodeling, by using a convolutional neural network. The outcomes of this study not only provide two BC-based bandages as multifunctional wound management, but also demonstrate a new strategy for the development of the next generation of smart bandage.


Assuntos
Celulose , Nanofios , Ratos , Animais , Prata , Fator A de Crescimento do Endotélio Vascular , Antibacterianos , Bandagens , Estimulação Elétrica
16.
J Colloid Interface Sci ; 657: 567-579, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38071806

RESUMO

Monitoring blood glucose level is critical, since its abnormality leads to diabetes and causes death, even though glucose is essential for human living. Herein, the sensing study was performed on electrochemical nonenzymatic glucose sensors, which are composed of an Au nanocluster (AuNC) catalyst deposited on a metallic nanotube array (MeNTA) and polypyrrole nanowire (PPyNW). The AuNC was produced by irradiating a femtosecond pulse laser to the Au precursor solution, and it is a simple and facile method. The successful deposition of AuNC on both MeNTA and PPyNW was confirmed by means of the surface morphology and the Au content increase. On the exploration by cyclic voltammetry in alkaline condition, AuNC/MeNTA electrodes showed better performance than AuNC/PPyNW electrodes: The former was a remarkable electrocatalytic detector towards glucose oxidation with better sensitivity, lower detection limit, wider linear range, and longer-term stability without interference from potential interfering agents such as ascorbic acid, urea, NaCl, KCl, etc. Moreover, nonenzymatic AuNC/MeNTA electrodes exhibited high precision and accuracy in real human blood samples and, thus, can be a promising candidate in glucose sensing applications.


Assuntos
Técnicas Biossensoriais , Nanotubos , Nanofios , Humanos , Polímeros , Pirróis , Nanofios/química , Técnicas Biossensoriais/métodos , Glucose/química , Eletrodos , Catálise , Técnicas Eletroquímicas
17.
Adv Sci (Weinh) ; 11(4): e2305890, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38039434

RESUMO

Biomaterials encounter considerable challenges in extensive bone defect regeneration. The amelioration of outcomes may be attainable through the orchestrated modulation of both innate and adaptive immunity. Silicon-hydroxyapatite, for instance, which solely focuses on regulating innate immunity, is inadequate for long-term bone regeneration. Herein, extra manganese (Mn)-doping is utilized for enhancing the osteogenic ability by mediating adaptive immunity. Intriguingly, Mn-doping engenders heightened recruitment of CD4+ T cells to the bone defect site, concurrently manifesting escalated T helper (Th) 2 polarization and an abatement in Th1 cell polarization. This consequential immune milieu yields a collaborative elevation of interleukin 4, secreted by Th2 cells, coupled with attenuated interferon gamma, secreted by Th1 cells. This orchestrated interplay distinctly fosters the osteogenesis of bone marrow stromal cells and effectuates consequential regeneration of the mandibular bone defect. The modulatory mechanism of Th1/Th2 balance lies primarily in the indispensable role of manganese superoxide dismutase (MnSOD) and the phosphorylation of adenosine 5'-monophosphate-activated protein kinase (AMPK). In conclusion, this study highlights the transformative potential of Mn-doping in amplifying the osteogenic efficacy of silicon-hydroxyapatite nanowires by regulating T cell-mediated adaptive immunity via the MnSOD/AMPK pathway, thereby creating an anti-inflammatory milieu favorable for bone regeneration.


Assuntos
Nanofios , Osteogênese , Manganês/farmacologia , Silício/farmacologia , Durapatita/farmacologia , Proteínas Quinases Ativadas por AMP/farmacologia
18.
Adv Mater ; 36(5): e2310979, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37994277

RESUMO

The immunomodulatory effect of divalent manganese cations (Mn2+ ), such as activation of the cGAS-STING pathway or NLRP3 inflammasomes, positions them as adjuvants for cancer immunotherapy. In this study, it is found that trace Mn2+ ions, bound to bovine serum albumin (BSA) to form Mn@BSA nanocomplexes, stimulate pro-inflammatory responses in human- or murine-derived macrophages through TLR4-mediated signaling cascades. Building on this, the assembly of Mn@BSA nanocomplexes to obtain nanowire structures enables stronger and longer-lasting immunostimulation of macrophages by regulating phagocytosis. Furthermore, Mn@BSA nanocomplexes and their nanowires efficiently activate peritoneal macrophages, reprogramme tumor-associated macrophages, and inhibit the growth of melanoma tumors in vivo. They also show better biosafety for potential clinical applications compared to typical TLR4 agonists such as lipopolysaccharides. Accordingly, the findings provide insights into the mechanism of metalloalbumin complexes as potential TLR agonists that activate macrophage polarization and highlight the importance of their nanostructures in regulating macrophage-mediated innate immunity.


Assuntos
Nanofios , Receptor 4 Toll-Like , Camundongos , Humanos , Animais , Receptor 4 Toll-Like/metabolismo , Manganês , Macrófagos/metabolismo , Soroalbumina Bovina/química
19.
Anal Chem ; 96(1): 599-605, 2024 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-38156620

RESUMO

Circular RNAs (circRNAs) represent an emerging category of endogenous transcripts characterized by long half-life time, covalently closed structures, and cell-/tissue-specific expression patterns, making them potential disease biomarkers. Herein, we demonstrate the construction of fluorescent G-quadruplex nanowires for label-free and accurate monitoring of circular RNAs in breast cancer cells and tissues by integrating proximity ligation-rolling circle amplification cascade with lighting up G-quadruplex. The presence of target circRNA facilitates the SplintR ligase-mediated ligation of the padlock probe. Upon the addition of primers, the ligated padlock probe can serve as a template to initiate subsequent rolling circle amplification (RCA), generating numerous long G-quadruplex nanowires that can incorporate with thioflavin T (ThT) to generate a remarkably improved fluorescence signal. Benefiting from good specificity of SplintR ligase-mediated ligation reaction and exponential amplification efficiency of RCA, this strategy can sensitively detect target circRNA with a limit of detection of 4.65 × 10-18 M. Furthermore, this method can accurately measure cellular circRNA expression with single-cell sensitivity and discriminate the circRNA expression between healthy para-carcinoma tissues and breast cancer tissues, holding great potential in studying the pathological roles of circRNA and clinic diagnostics.


Assuntos
Neoplasias da Mama , Nanofios , Humanos , Feminino , RNA Circular , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Corantes Fluorescentes/química , Ligases , Técnicas de Amplificação de Ácido Nucleico/métodos
20.
Small ; 20(19): e2309230, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38112271

RESUMO

Bone infection poses a major clinical challenge that can hinder patient recovery and exacerbate postoperative complications. This study has developed a bioactive composite scaffold through the co-assembly and intrafibrillar mineralization of collagen fibrils and zinc oxide (ZnO) nanowires (IMC/ZnO). The IMC/ZnO exhibits bone-like hierarchical structures and enhances capabilities for osteogenesis, antibacterial activity, and bacteria-infected bone healing. During co-cultivation with human bone marrow mesenchymal stem cells (BMMSCs), the IMC/ZnO improves BMMSC adhesion, proliferation, and osteogenic differentiation even under inflammatory conditions. Moreover, it suppresses the activity of Gram-negative Porphyromonas gingivalis and Gram-positive Streptococcus mutans by releasing zinc ions within the acidic infectious microenvironment. In vivo, the IMC/ZnO enables near-complete healing of infected bone defects within the intricate oral bacterial milieu, which is attributed to IMC/ZnO orchestrating M2 macrophage polarization, and fostering an osteogenic and anti-inflammatory microenvironment. Overall, these findings demonstrate the promise of the bioactive scaffold IMC/ZnO for treating bacteria-infected bone defects.


Assuntos
Regeneração Óssea , Colágeno , Células-Tronco Mesenquimais , Nanofios , Osteogênese , Alicerces Teciduais , Óxido de Zinco , Óxido de Zinco/química , Óxido de Zinco/farmacologia , Nanofios/química , Regeneração Óssea/efeitos dos fármacos , Alicerces Teciduais/química , Humanos , Colágeno/química , Células-Tronco Mesenquimais/citologia , Osteogênese/efeitos dos fármacos , Animais , Porphyromonas gingivalis/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Streptococcus mutans/fisiologia , Streptococcus mutans/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos
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