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1.
Biochem Biophys Res Commun ; 699: 149496, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38290175

RESUMEN

BACKGROUND: Peripheral nerve injury (PNI) presents a significant clinical challenge, leading to enduring sensory-motor impairments. While mesenchymal stem cell (MSC)-based therapy holds promise for PNI treatment, enhancing its neurotrophic effects remains crucial. Platelet-rich plasma-derived exosomes (PRP-Exo), rich in bioactive molecules for intercellular communication, offer potential for modulating cellular biological activity. METHODS: PRP-Exo was isolated, and its impact on MSC viability was evaluated. The effects of PRP-Exo-treated MSCs (MSCPExo) on Schwann cells (SCs) from injured sciatic nerves and human umbilical vein endothelial cells (HUVECs) were assessed. Furthermore, the conditioned medium from MSCPExo (MSCPExo-CM) was analyzed using a cytokine array and validated through ELISA and Western blot. RESULTS: PRP-Exo enhanced MSC viability. Coculturing MSCPExo with SCs ameliorated apoptosis and promoted SC proliferation following PNI. Similarly, MSCPExo-CM exhibited pro-proliferative, migratory, and angiogenic effects. Cytokine array analysis identified 440 proteins in the MSCPExo secretome, with 155 showing upregulation and 6 showing downregulation, many demonstrating potent pro-regenerative properties. ELISA confirmed the enrichment of several angiotrophic and neurotrophic factors. Additionally, Western blot analysis revealed the activation of the PI3K/Akt signaling pathway in MSCPExo. CONCLUSION: Preconditioning MSCs with PRP-Exo enhanced the paracrine function, particularly augmenting neurotrophic and pro-angiogenic secretions, demonstrating an improved potential for neural repair.


Asunto(s)
Exosomas , Células Madre Mesenquimatosas , Plasma Rico en Plaquetas , Humanos , Exosomas/metabolismo , Células Endoteliales , Fosfatidilinositol 3-Quinasas/metabolismo , Citocinas/metabolismo , Regeneración Nerviosa
2.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 45(3): 374-381, 2023 Jun.
Artículo en Zh | MEDLINE | ID: mdl-37106519

RESUMEN

Objective To investigate the effect of human platelet-rich plasma-derived exosomes(PRP-exos)on the proliferation of Schwann cell(SC)cultured in vitro. Methods PRP-exos were extracted by polymerization-precipitation combined with ultracentrifugation.The morphology of PRP-exos was observed by transmission electron microscopy,and the concentration and particle size distribution of PRP-exos were determined by nanoparticle tracking analysis.Western blotting was employed to determine the expression of the marker proteins CD63,CD81,and CD9 on exosome surface and the platelet membrane glycoprotein CD41.The SCs of rats were isolated and cultured,and the expression of the SC marker S100ß was detected by immunofluorescence staining.The fluorescently labeled PRP-exos were co-cultured with SCs in vitro for observation of their interaction.EdU assay was employed to detect the effect of PRP-exos on SC proliferation,and CCK-8 assay to detect the effects of PRP-exos at different concentrations(0,10,20,40,80,and 160 µg/ml)on SC proliferation. Results The extracted PRP-exos appeared as uniform saucer-shaped vesicles with the average particle size of(122.8±38.7)nm and the concentration of 3.5×1012 particles/ml.CD63,CD81,CD9,and CD41 were highly expressed on PRP-exos surface(P<0.001,P=0.025,P=0.004,and P=0.032).The isolated SCs expressed S100ß,and PRP-exos could be taken up by SCs.PRP-exos of 40,80,and 160 µg/ml promoted the proliferation of SCs,and that of 40 µg/ml showed the best performance(all P<0.01). Conclusions High concentrations of PRP-exos can be extracted from PRP.PRP-exos can be taken up by SCs and promote the proliferation of SCs cultured in vitro.


Asunto(s)
Exosomas , Plasma Rico en Plaquetas , Humanos , Ratas , Animales , Exosomas/metabolismo , Células de Schwann , Técnicas de Cocultivo , Proliferación Celular , Células Cultivadas
3.
Small ; 17(30): e2101093, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34145751

RESUMEN

Effective and reliable encapsulation of phase change materials (PCMs) is essential and critical to the high-performance solar-thermal energy harvesting and storage. However, challenges remain pertaining to manufacturing scalability, high efficiency in energy storage/release, and anti-leakage of melted PCMs. Herein, inspired by natural legume, a facile and scalable extrusion-based core-sheath 3D printing strategy is demonstrated for directly constructing bean-pod-structured octadecane (OD)/graphene (BOG) phase change microlattices, with regular porous configuration as well as individual and effective encapsulation of OD "beans" into highly interconnected graphene network wrapping layer built by closely stacked and aligned graphene sheets. The unique architectural features enable the ready spreading of light into the interior of phase change microlattice, a high transversal thermal conductivity of 1.67 W m-1 K-1 , and rapid solar-thermal energy harvesting and transfer, thereby delivering a high solar-thermal energy storage efficiency, and a large phase change enthalpy of 190 J g-1 with 99.1% retention after 200 cycles. Most importantly, such encapsulated PCMs feature an exceptional thermal reliability and stability, with no leakage and shape variation even at 1000 thermal cycles and partial damage of BOG. This work validates the feasibility of scalably printing practical encapsulated PCMs, which may revolutionize the fabrication of composite PCMs for solar-thermal energy storage devices.


Asunto(s)
Fabaceae , Calor , Impresión Tridimensional , Reproducibilidad de los Resultados , Conductividad Térmica
4.
Small ; 17(5): e2006181, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33432780

RESUMEN

To address the lack of a suitable electrolyte that supports the stable operation of the electrochemical yarn muscles in air, an ionic-liquid-in-nanofibers sheathed carbon nanotube (CNT) yarn muscle is prepared. The nanofibers serve as a separator to avoid the short-circuiting of the yarns and a reservoir for ionic liquid. The ionic-liquid-in-nanofiber-sheathed yarn muscles are strong, providing an isometric stress of 10.8 MPa (about 31 times the skeletal muscles). The yarn muscles are highly robust, which can reversibly contract stably at such conditions as being knotted, wide-range humidity (30 to 90 RH%) and temperature (25 to 70 °C), and long-term cycling and storage in air. By utilizing the accumulated isometric stress, the yarn muscles achieve a high contraction rate of 36.3% s-1 . The yarn muscles are tightly bundled to lift heavy weights and grasp objects. These unique features can make the strong and robust yarn muscles as a desirable actuation component for robotic devices.


Asunto(s)
Líquidos Iónicos , Nanofibras , Nanotubos de Carbono , Electrólitos , Músculo Esquelético
5.
Microb Pathog ; 150: 104732, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33429052

RESUMEN

Streptococcus suis (S. suis) is a gram-positive coccus that causes disease in humans and animals. The codon usage pattern of bacteria reveals a range of evolutionary changes that assist them to enhance tolerance to environments. To better understand the genetic features during the evolution of S. suis, we performed codon usage analysis. Nine pathogenic strains of different serotypes and different geographical distribution were analyzed to better understand the differences in their evolutionary process. Nucleotide compositions and relative synonymous codon usage (RSCU) analysis revealed that A/T-ending codons are dominant in S. suis. Neutrality analysis, correspondence analysis and ENC-plot results revealed that natural selection is the predominant element prompting codon usage. Cluster analysis based on RSCU was roughly consistent with the dendrogram rooted genomic BLAST analysis. Comparison of synonymous codon usage pattern between S. suis and susceptible hosts (H. sapiens and S. scrofa) revealed that the codon usage of S. suis is separated from the synonymous codon usage of susceptible hosts. The CAI values implied that S. suis includes a series of predicted highly expressed coding sequences contained in metabolism and transcriptional regulation, revealing the necessity of this pathogen to deal with various environmental conditions. The study of codon usage in S. suis may provide evidence involving the molecular evolution of bacteria and a better understanding of evolutionary relationships between S. suis and its corresponding hosts.


Asunto(s)
Uso de Codones , Streptococcus suis , Animales , Codón/genética , Evolución Molecular , Humanos , Selección Genética , Streptococcus suis/genética
6.
Nanotechnology ; 32(26)2021 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-33730705

RESUMEN

We investigated the microstructures of carbon nanotube (CNT) films and the effect of CNT length on their mechanical performance. 230 µm-, 300 µm-, and 360 µm- long CNTs were grown and used to fabricate CNT films by a winding process. Opposite from the length effect on CNT fibers, it has been found that the mechanical properties of the CNT films decrease with increasing CNT length. Without fiber twisting, short CNTs tend to bundle together tightly by themselves in the film structure, resulting in an enhanced packing density; meanwhile, they also provide a high degree of CNT alignment, which prominently contributes to high mechanical properties of the CNT films. When CNTs are long, they tend to be bent and entangled, which significantly reduce their packing density, impairing the film mechanical behaviors severely. It has also been unveiled that the determinant effect of the CNT alignment on the film mechanical properties is more significant than that of the film packing density. These findings provide guidance on the optimal CNT length when attempting to fabricate high-performance macroscopic CNT assemblies.

7.
Nanotechnology ; 32(49)2021 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-34433147

RESUMEN

Carbon nanotube (CNT) films have demonstrated great potential for highly efficient thermal management materials. However, how to enable a combined feature of excellent thermal conductivity and structural robustness, which is crucial for the high-performance realization, still remains challenging. Herein, an effective and facile strategy to solve the problem was proposed by developing a graphene (G)/CNT film with highly aligned welding of ultrathin G layer to robust CNT film. The unique architectural features of the obtained composite film enabled a high tensile strength (116 MPa) and electric conductivity (1.7 × 103S cm-1). Importantly, the thermal conductivity was significantly improved compared to neat CNT film, and reached as high as 174 W m-1K-1. In addition, the G/CNT film featured a superior electromagnetic shielding performance. This work provides useful guidelines for designing and fabricating the composite CNT film with prominent thermal conductivity, as well as excellent mechanical and electrical properties.

8.
Nano Lett ; 19(3): 1577-1586, 2019 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-30798604

RESUMEN

Soft and magnetic resonance imaging (MRI) compatible neural electrodes enable stable chronic electrophysiological measurements and anatomical or functional MRI studies of the entire brain without electrode interference with MRI images. These properties are important for many studies, ranging from a fundamental neurophysiological study of functional MRI signals to a chronic neuromodulatory effect investigation of therapeutic deep brain stimulation. Here we develop soft and MRI compatible neural electrodes using carbon nanotube (CNT) fibers with a diameter from 20 µm down to 5 µm. The CNT fiber electrodes demonstrate excellent interfacial electrochemical properties and greatly reduced MRI artifacts than PtIr electrodes under a 7.0 T MRI scanner. With a shuttle-assisted implantation strategy, we show that the soft CNT fiber electrodes can precisely target specific brain regions and record high-quality single-unit neural signals. Significantly, they are capable of continuously detecting and isolating single neuronal units from rats for up to 4-5 months without electrode repositioning, with greatly reduced brain inflammatory responses as compared to their stiff metal counterparts. In addition, we show that due to their high tensile strength, the CNT fiber electrodes can be retracted controllably postinsertion, which provides an effective and convenient way to do multidepth recording or potentially selecting cells with particular response properties. The chronic recording stability and MRI compatibility, together with their small size, provide the CNT fiber electrodes unique research capabilities for both basic and applied neuroscience studies.

9.
BMC Genomics ; 20(1): 670, 2019 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-31438846

RESUMEN

BACKGROUND: Postoperative cognitive dysfunction (POCD) affects a large number of post-surgery patients, especially for the elderly. However, the etiology of this neurocognitive disorder is largely unknown. Even if several studies have reported a small number of miRNAs as the essential modulatory factors in POCD, these findings are still rather limited. The aim of current study was to screen the POCD-related miRNAs in the hippocampus tissues and investigate the target genes of differentially expressed miRNAs and their biological functions underlying POCD pathophysiology. METHODS: The miRNA microarray was used to find the abnormal expression of miRNAs in the hippocampus tissues from the POCD model mice to normal mice (Discovery cohort, 3 vs 3). The nominal significant results were validated in an independent sample of hippocampus tissues of 10 mice based on same miRNA microarray (Replication cohort, 5 vs 5). Expression level of the most significantly abnormal miRNA was further validated by real-time quantitative polymerase chain reaction (PCR). To determine the expression pattern among miRNAs and genes and detect the interactions, we conducted a weighted gene co-expression network analysis (WGCNA) in the miRNAs and genes expression data from hippocampus tissue of wild type mice (n = 24). The target genes of miRNAs were predicted using the miRWalk3.0 software. Furthermore, we used the ClueGO software to decipher the pathways network and reveal the biological functions of target genes of miRNAs. RESULTS: We found that nine miRNAs showed significant associations with POCD in both datasets. Among these miRNAs, mmu-miR-190a-3p was the most significant one. By performing WGCNA analysis, we found 25 co-expression modules, of which mmu-miR-190a-3p was significantly anti-correlated with red module. Moreover, in the red module, 314 genes were significantly enriched in four pathways such as axon guidance and calcium signaling pathway, which are well-documented to be associated with psychiatric disorders and brain development. Also, 169 of the 314 genes were highly correlated with mmu-miR-190a-3p, and four genes (Sphkap, Arhgef25, Tiam1, and Ntrk3) had putative binding sites at 3'-UTR of mmu-miR-190a-3p. Based on protein-protein network analysis, we detected that Tiam1 was a central gene regulated by the mmu-miR-190a-3p. CONCLUSIONS: Taken together, we conclude that mmu-miR-190a-3p is involved in the etiology of POCD and may serve as a novel predictive indicator for POCD.


Asunto(s)
MicroARNs/genética , Complicaciones Cognitivas Postoperatorias/genética , Proteína 1 de Invasión e Inducción de Metástasis del Linfoma-T/genética , Animales , Redes Reguladoras de Genes , Masculino , Aprendizaje por Laberinto , Ratones , Ratones Endogámicos C57BL , Complicaciones Cognitivas Postoperatorias/fisiopatología , Transcriptoma
11.
J Neuroinflammation ; 14(1): 17, 2017 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-28109286

RESUMEN

BACKGROUND: Considerable evidence has shown that neuroinflammation and oxidative stress play an important role in the pathophysiology of postoperative cognitive dysfunction (POCD) and other progressive neurodegenerative disorders. Increasing evidence suggests that acetaminophen (APAP) has unappreciated antioxidant and anti-inflammatory properties. However, the impact of APAP on the cognitive sequelae of inflammatory and oxidative stress is unknown. The objective of this study is to explore whether APAP could have neuroprotective effects on lipopolysaccharide (LPS)-induced cognitive impairment in mice. METHODS: A mouse model of LPS-induced cognitive impairment was established to evaluate the neuroprotective effects of APAP against LPS-induced cognitive impairment. Adult C57BL/6 mice were treated with APAP half an hour prior to intracerebroventricular microinjection of LPS and every day thereafter, until the end of the study period. The Morris water maze was used to assess cognitive function from postinjection days 1 to 3. Animal behavioural tests as well as pathological and biochemical assays were performed to evaluate LPS-induced hippocampal damage and the neuroprotective effect of APAP. RESULTS: Mice treated with LPS exhibited impaired performance in the Morris water maze without changing spontaneous locomotor activity, which was ameliorated by treatment with APAP. APAP suppressed the accumulation of pro-inflammatory cytokines and microglial activation induced by LPS in the hippocampus. In addition, APAP increased SOD activity, reduced MDA levels, modulated glycogen synthase kinase 3ß (GSK3ß) activity and elevated brain-derived neurotrophic factor (BDNF) expression in the hippocampus. Moreover, APAP significantly decreased the Bax/Bcl-2 ratio and neuron apoptosis in the hippocampus of LPS-treated mice. CONCLUSIONS: Our results suggest that APAP may possess a neuroprotective effect against LPS-induced cognitive impairment and inflammatory and oxidative stress via mechanisms involving its antioxidant and anti-inflammatory properties, as well as its ability to inhibit the mitochondrial permeability transition (MPT) pore and the subsequent apoptotic pathway.


Asunto(s)
Acetaminofén/farmacología , Antioxidantes/farmacología , Disfunción Cognitiva , Hipocampo/efectos de los fármacos , Animales , Disfunción Cognitiva/inducido químicamente , Lipopolisacáridos/toxicidad , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Actividad Motora/efectos de los fármacos , Fármacos Neuroprotectores/farmacología
12.
Small ; 12(15): 2035-45, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26929042

RESUMEN

To date, it has been a great challenge to design high-performance flexible energy storage devices for sufficient loading of redox species in the electrode assemblies, with well-maintained mechanical robustness and enhanced electron/ionic transport during charge/discharge cycles. An electrochemical activation strategy is demonstrated for the facile regeneration of carbon nanotube (CNT) film prepared via floating catalyst chemical vapor deposition strategy into a flexible, robust, and highly conductive hydrogel-like film, which is promising as electrode matrix for efficient loading of redox species and the fabrication of high-performance flexible pseudosupercapacitors. The strong and conductive CNT films can be effectively expanded and activated by electrochemical anodic oxygen evolution reaction, presenting greatly enhanced internal space and surface wettability with well-maintained strength, flexibility, and conductivity. The as-formed hydrogel-like film is quite favorable for electrochemical deposition of manganese dioxide (MnO2 ) with loading mass up to 93 wt% and electrode capacitance kept around 300 F g(-1) (areal capacitance of 1.2 F cm(-2) ). This hybrid film was further used to assemble a flexible symmetric pseudosupercapacitor without using any other current collectors and conductive additives. The assembled flexible supercapacitors exhibited good rate performance, with the areal capacitance of more than 300 mF cm(-2) , much superior to other reported MnO2 based flexible thin-film supercapacitors.

13.
Small ; 11(31): 3830-6, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25941071

RESUMEN

In order to maximize the carbon nanotube (CNT) buckypaper properties, it is critical to improve their alignment and reduce their waviness. In this paper, a novel approach, microcombing, is reported to fabricate aligned CNT films with a uniform structure. High level of nanotube alignment and straightness was achieved using sharp surgical blades with microsized features at the blade edges to comb single layer of CNT sheet. These microcombs also reduced structural defects within the film and enhanced the nanotube packing density. Following the microcombing approach, the as-produced CNT films demonstrated a tensile strength of up to 3.2 GPa, Young's modulus of up to 172 GPa, and electrical conductivity of up to 1.8 × 10(5) S m(-1) , which are much superior to previously reported CNT films or buckypapers. More importantly, this novel technique requires less rigorous process control and can construct CNT films with reproducible properties.

14.
Phys Chem Chem Phys ; 17(11): 7104-8, 2015 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-25705030

RESUMEN

Fibrous all-carbon woven memory devices have been formed by using reduced acid graphene oxide as a switching material, and flexible carbon nanotube fibers as electrodes. The as prepared fibrous all-carbon woven memory devices exhibited an ultra-high ON/OFF current ratio of 10(9), a fast switching speed of 3 ms, and a long life time of at least 500 cycles that could pave the way for future e-textiles.

15.
Small ; 10(22): 4606-25, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25123967

RESUMEN

Assembly of carbon nanotubes (CNTs) in effective and productive ways is of vital importance to their application. Recent progress in synthesis of CNTs has inspired new strategies for utilizing the unique physiochemical properties of CNTs in macroscale materials and devices. Assembling CNTs by dry processes (e.g., directly collecting CNTs in the form of freestanding films followed by pressing, stretching, and multilayer stacking instead of dispersing them in solution) not only considerably simplifies the processes but also avoids structural damage to the CNTs. Various dry-processable CNTs are reviewed, focusing on their synthesis, properties, and applications. The synthesis techniques are organized in terms of aggregative morphologies and microstructure control of CNTs. Important applications such as functional thin-film devices, strong CNT films, and composites are included. The opportunities and challenges in the synthesis techniques and fabrication of advanced composites and devices are discussed.

16.
World Neurosurg ; 185: e1086-e1092, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38490441

RESUMEN

OBJECTIVE: This study aimed to examine the mechanism of occipital condyle fractures (OCFs), their clinical symptoms, computer tomography (CT) scan findings, treatment options, and classification. METHODS: A retrospective analysis was conducted on 43 patients with OCFs who were admitted to our neurosurgery center between 2017 and 2023. RESULTS: The investigation covered their clinical symptoms, CT scan results, and treatment outcomes. It was found that 25.6% of the patients suffered from severe craniocerebral injuries with Glasgow Coma Scale (GCS) scores of 3-8 points, 9.3% had moderate injuries with GCS scores of 9-12 points, and 65.1% exhibited mild injuries with GCS scores of 13-15 points. Of these patients, 90.7% showed improvement upon discharge, 4.7% succumbed to their injuries, and another 4.7% developed paraplegia. Symptoms indicative of OCF in individuals with CCJ injuries included neck pain, swelling, cranial nerve palsy, and posterior pharyngeal wall swelling. Frequently observed complications in OCF patients included cerebral contusion, occipital bone fractures, and skull base fractures. Employing thin-layer CT scans of the CCJ area, along with sagittal and coronal CT reconstructions, is essential for identifying OCFs. The fractures were classified into 3 types based on the Anderson-Montesano classification, which, when modified, provides enhanced treatment guidance. CONCLUSIONS: OCFs are predominantly present in cases of high-energy trauma, with high-resolution thin-layer CT scans serving as the preferred diagnostic method. The application of the modified Anderson-Montesano classification, distinguishing between stable and unstable fractures, facilitates the determination of suitable treatment strategies. Stable OCFs can be managed using a rigid neck brace, while unstable OCFs may require Halo-vest frame fixation or surgical intervention.


Asunto(s)
Hueso Occipital , Humanos , Estudios Retrospectivos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Hueso Occipital/diagnóstico por imagen , Hueso Occipital/lesiones , Hueso Occipital/cirugía , Adulto Joven , Adolescente , Anciano , Tomografía Computarizada por Rayos X , Fracturas Craneales/diagnóstico por imagen , Fracturas Craneales/cirugía , Escala de Coma de Glasgow , Resultado del Tratamiento
17.
Int J Biol Macromol ; 270(Pt 1): 132381, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38754664

RESUMEN

Florfenicol (FF), with its broad-spectrum antibacterial activity, is frequently abused in the livestock and poultry industries and has aroused the growing public concern. Owing to structural similarities and varying maximum residue limits between florfenicol and other chloramphenicol (CAP)-type antibiotics, including thiamphenicol (TAP) and chloramphenicol (CAP), there is an urgent need for a rapid and effective immunoassay method to distinguish them, in order to minimize the risk of false positives. Fortunately, a highly specific monoclonal antibody (mAb), named as SF11, has been developed using hybridoma technology. Molecular simulations have revealed that the mAb SF11's specificity in recognizing florfenicol stems from the π-π stacking interaction between florfenicol and the mAb SF11 binding pocket. Using this highly specific mAb, a sensitive time-resolved fluorescence immunochromatographic assay (TRFICA) strip for rapid florfenicol detection has been developed. Under optimal conditions, this TRFICA demonstrated good analytical performance for the detection of florfenicol in milk and eggs samples, with the half-maximal inhibition concentration (IC50) values of 1.89 and 2.86 ng mL-1, the limit of detection (LOD) of 0.23 and 0.48 ng mL-1, the cut-off values of 62.50 and 31.25 ng mL-1, and the testing time of approximately thirteen minutes. Spiked recoveries in the milk and eggs samples ranged from 104.7 % to 112.3 % and 95.3 % to 116.4 %, respectively, with no obvious cross-reactions with the other analogues observed. The TRFICA results correlated well with those of high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) for real samples, indicating that the developed TRFICA method was sensitive, accurate and adapted for the rapid determination of florfenicol in milk and egg samples.


Asunto(s)
Anticuerpos Monoclonales , Huevos , Leche , Tianfenicol , Tianfenicol/análogos & derivados , Tianfenicol/análisis , Leche/química , Animales , Huevos/análisis , Anticuerpos Monoclonales/química , Residuos de Medicamentos/análisis , Inmunoensayo/métodos , Cromatografía de Afinidad/métodos , Antibacterianos/análisis , Antibacterianos/química , Contaminación de Alimentos/análisis
18.
Foods ; 13(3)2024 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-38338560

RESUMEN

Picoxystrobin (PIC) is a fungicide extensively used for disease control in both crops and vegetables. Residues of PIC in vegetables pose a potential threat to human health due to their accumulation in the food chain. In this study, a specific PIC monoclonal antibody (mAb) was developed by introducing a carboxylic acid arm into PIC and subsequently preparing a hapten and an artificial antigen. A sensitive and rapid time-resolved fluorescence immunochromatographic assay (TRFICA) was established based on the mAb. Subsequently, using a time-resolved fluorescent microsphere (TRFM) as signal probe, mAbs and microspheres were covalently coupled. The activated pH, the mAb diluents, the mAb amount, and the probe amount were optimized. Under optimized conditions, the quantitative limits of detection (qLOD) of PIC in cucumber, green pepper, and tomato using TRFICA were established at 0.61, 0.26, and 3.44 ng/mL, respectively; the 50% inhibiting concentrations (IC50) were 11.76, 5.29, and 37.68 ng/mL, respectively. The linear ranges were 1.81-76.71, 0.80-35.04, and 8.32-170.55 ng/mL, respectively. The average recovery in cucumber, green pepper, and tomato samples ranged from 79.8% to 105.0%, and the corresponding coefficients of variation (CV) were below 14.2%. In addition, 15 vegetable samples were selected and compared with the results obtained using ultra-performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS). The results revealed a high degree of concordance between the proposed method and UPLC-MS/MS. In conclusion, the devised TRFICA method is a valuable tool for rapid, on-site, and highly sensitive detection of PIC residues in vegetables.

19.
Food Chem ; 450: 139372, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-38640545

RESUMEN

Based on the size and surface properties of dimethomorph and flumorph, we used a computer simulation-assisted size exclusion hapten design strategy to develop group-specific monoclonal antibodies that can simultaneously recognize dimethomorph and flumorph. For this, we performed quantitative and visual semi-quantitative time-resolved fluorescence immunochromatography (TRFICA) to simultaneously detect dimethomorph and flumorph in potatoes and apples. In potato samples, the visual limit of detection (vLOD) for dimethomorph and flumorph was 4 ng/mL and 8 ng/mL, respectively, whereas the quantitative limit of detection (qLOD) for dimethomorph and flumorph was 0.26 and 0.33 ng/mL, respectively. The vLOD of dimethomorph and flumorph in apple samples was 8 ng/mL, whereas the qLOD of dimethomorph and flumorph was 0.17 and 0.38 ng/mL, respectively. The average recovery of potato and apple samples ranged from 77.5% to 121.7%, which indicated that the method can be used to rapidly detect dimethomorph and flumorph in food samples.


Asunto(s)
Cromatografía de Afinidad , Contaminación de Alimentos , Haptenos , Malus , Solanum tuberosum , Solanum tuberosum/química , Haptenos/química , Malus/química , Contaminación de Alimentos/análisis , Cromatografía de Afinidad/métodos , Cromatografía de Afinidad/instrumentación , Anticuerpos Monoclonales/química , Límite de Detección , Fungicidas Industriales/análisis
20.
Nanomaterials (Basel) ; 14(13)2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38998704

RESUMEN

With the widespread use of electronic devices, electromagnetic interference (EMI) has become an increasingly severe issue, adversely affecting device performance and human health. Carbon nanotubes (CNTs) are recognized for their electrical conductivity, flexibility, and stability, making them promising candidates for EMI shielding applications. This research developed hierarchical porous-structured CNT/carbon composites for enhancing electromagnetic interference (EMI) shielding properties. Featuring a CNT film with nano-scale pores and an amorphous carbon layer with micro-scale pores, the CNT/carbon composites are strategically arranged to promote the penetration of EM waves into the composite's interior and facilitate multiple reflections, thereby improving the EMI shielding performance. An impressive EMI shielding effectiveness of 61.4 dB was achieved by the CNT/carbon composites, marking a significant improvement over the 36.5 dB measured for the pristine CNT film. Owing to the micro pores in the amorphous carbon layer, a notable reduction in the reflection shielding efficiency (SER) but, concurrently, a substantial increase in the absorption shielding efficiency (SEA) compared with the pristine CNT film was realized in the composites. This study successfully validated the effectiveness of the hierarchical porous structure in enhancing the EMI shielding performance, providing a promising new strategy for the development of lightweight, flexible, and efficient EMI shielding materials.

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