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1.
Biosens Bioelectron ; 259: 116380, 2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38754193

RESUMEN

Exosomes, as novel biomarker for liquid biopsy, exhibit huge important potential value for cancer diagnosis. However, various proteins show different expression levels on exosomal membrane, and the absolute concentration of exosomes in clinical samples is easily influenced by a number of factors. Here, we developed a CRISPR/Cas12a and aptamer-chemiluminescence based analysis (CACBA) for the relative abundance determination of tumor-related protein positive exosomes in plasma for breast cancer diagnosis. The total concentration of exosomes was determined through captured CD63 using a CRISPR/Cas12a-based method with the LoD of 8.97 × 103 particles/µl. Meanwhile, EpCAM and MUC1 positive exosomes were quantitatively detected by aptamer-chemiluminescence (ACL) based method with the LoD of 1.45 × 102 and 3.73 × 102 particles/µl, respectively. It showed that the percentages of EpCAM and MUC1 positive exosomes offered an excellent capability to differentiate breast cancer patients and healthy donors. The high sensitivity, strong specificity, outstanding anti-interference capability, and steady recovery rate of this approach offered higher accuracy and robustness than the commercialized method in clinical trial. In addition with good stability, easy preparation and low cost, this method not only provides a new approach to rapid analysis of exosome proteins, it may be quickly extended to the diagnoses of various cancers.

2.
Adv Sci (Weinh) ; : e2400446, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38639386

RESUMEN

Despite accumulating evidence linking defective lysosome function with autoimmune diseases, how the catabolic machinery is regulated to maintain immune homeostasis remains unknown. Late endosomal/lysosomal adaptor, MAPK and mTOR activator 5 (Lamtor5) is a subunit of the Ragulator mediating mechanistic target of rapamycin complex 1 (mTORC1) activation in response to amino acids, but its action mode and physiological role are still unclear. Here it is demonstrated that Lamtor5 level is markedly decreased in peripheral blood mononuclear cells (PBMCs) of patients with systemic lupus erythematosus (SLE). In parallel, the mice with myeloid Lamtor5 ablation developed SLE-like manifestation. Impaired lysosomal function and aberrant activation of mTORC1 are evidenced in Lamtor5 deficient macrophages and PBMCs of SLE patients, accompanied by blunted autolysosomal pathway and undesirable inflammatory responses. Mechanistically, it is shown that Lamtor5 is physically associated with ATP6V1A, an essential subunit of vacuolar H+-ATPase (v-ATPase), and promoted the V0/V1 holoenzyme assembly to facilitate lysosome acidification. The binding of Lamtor5 to v-ATPase affected the lysosomal tethering of Rag GTPase and weakened its interaction with mTORC1 for activation. Overall, Lamtor5 is identified as a critical factor for immune homeostasis by intergrading v-ATPase activity, lysosome function, and mTOR pathway. The findings provide a potential therapeutic target for SLE and/or other autoimmune diseases.

3.
Biosensors (Basel) ; 14(4)2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38667191

RESUMEN

Exosomes constitute an emerging biomarker for cancer diagnosis because they carry multiple proteins that reflect the origins of the parent cell. The highly sensitive detection of exosomes is a crucial prerequisite for the diagnosis of cancer. In this study, we report an exosome detection system based on quantum weak value amplification (WVA). The WVA detection system consists of a reflection detection light path and a Zr-ionized biochip. Zr-ionized biochips effectively capture exosomes through the specific interaction between zirconium dioxide and the phosphate groups on the lipid bilayer of exosomes. Aptamer-modified gold nanoparticles (Au NPs) are then used to specifically recognize proteins on exosomes to enhance the detection signal. The sensitivity and resolution of the detection system are 2944.07 nm/RIU and 1.22 × 10-5 RIU, respectively. The concentration of exosomes can be directly quantified by the WVA system, ranging from 105-107 particles/mL with the detection limit of 3 × 104 particles/mL. The use of Au NPs-EpCAM for the specific enhancement of breast cancer MDA-MB-231 exosomes is demonstrated. The results indicate that the WVA detection system can be a promising candidate for the detection of exosomes as tumor markers.


Asunto(s)
Técnicas Biosensibles , Neoplasias de la Mama , Exosomas , Oro , Nanopartículas del Metal , Humanos , Neoplasias de la Mama/diagnóstico , Femenino , Oro/química , Nanopartículas del Metal/química , Biomarcadores de Tumor , Línea Celular Tumoral , Límite de Detección , Circonio/química
4.
Microbiol Res ; 281: 127627, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38262205

RESUMEN

Cells are the essential building blocks of living organisms, responsible for carrying out various biochemical reactions and performing specific functions. In eukaryotic cells, numerous membrane organelles have evolved to facilitate these processes by providing specific spatial locations. In recent years, it has also been discovered that membraneless organelles play a crucial role in the subcellular organization of bacteria, which are single-celled prokaryotic microorganisms characterized by their simple structure and small size. These membraneless organelles in bacteria have been found to undergo Liquid-Liquid phase separation (LLPS), a molecular mechanism that allows for their assembly. Through extensive research, the occurrence of LLPS and its role in the spatial organization of bacteria have been better understood. Various biomacromolecules have been identified to exhibit LLPS properties in different bacterial species. LLPS which is introduced into synthetic biology applies to bacteria has important implications, and three recent research reports have shed light on its potential applications in this field. Overall, this review investigates the molecular mechanisms of LLPS occurrence and its significance in bacteria while also considering the future prospects of implementing LLPS in synthetic biology.


Asunto(s)
Orgánulos , Separación de Fases , Orgánulos/química , Bacterias/genética
5.
Biomed Pharmacother ; 171: 116129, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38194738

RESUMEN

Listeria monocytogenes (Lm), a foodborne bacterium, can infect people and has a high fatality rate in immunocompromised individuals. Listeriolysin O (LLO), the primary virulence factor of Lm, is critical in regulating the pathogenicity of Lm. This review concludes that LLO may either directly or indirectly activate a number of host cell viral pathophysiology processes, such as apoptosis, pyroptosis, autophagy, necrosis and necroptosis. We describe the invasion of host cells by Lm and the subsequent removal of Lm by CD8 T cells and CD4 T cells upon receipt of the LLO epitopes from major histocompatibility complex class I (MHC-I) and major histocompatibility complex class II (MHC-II). The development of several LLO-based vaccines that make use of the pore-forming capabilities of LLO and the immune response of the host cells is then described. Finally, we conclude by outlining the several natural substances that have been shown to alter the three-dimensional conformation of LLO by binding to particular amino acid residues of LLO, which reduces LLO pathogenicity and may be a possible pharmacological treatment for Lm.


Asunto(s)
Toxinas Bacterianas , Proteínas de Choque Térmico , Proteínas Hemolisinas , Listeria monocytogenes , Listeriosis , Humanos , Listeriosis/prevención & control , Linfocitos T CD8-positivos , Inmunidad
6.
Biochem Pharmacol ; 220: 116011, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38154548

RESUMEN

Sinularin, a natural product that purified from soft coral, exhibits anti-tumor effects against various human cancers. However, the mechanisms are not well understood. In this study, we demonstrated that Sinularin inhibited the viability of human prostate cancer cells in a dose-dependent manner and displayed significant cytotoxicity only at high concentration against normal prostate epithelial cell RWPE-1. Flow cytometry assay demonstrated that Sinularin induced tumor cell apoptosis. Further investigations revealed that Sinularin exerted anti-tumor activity through intrinsic apoptotic pathway along with up-regulation of pro-apoptotic protein Bax and PUMA, inhibition of anti-apoptotic protein Bcl-2, mitochondrial membrane potential collapses, and release of mitochondrial proteins. Furthermore, we illustrated that Sinularin induced cell apoptosis via up-regulating PUMA through inhibition of FOXO3 degradation by the ubiquitin-proteasome pathway. To explore how Sinularin suppress FOXO3 ubiquitin-proteasome degradation, we tested two important protein kinases AKT and ERK that regulate FOXO3 stabilization. The results revealed that Sinularin stabilized and up-regulated FOXO3 via inhibition of AKT- and ERK1/2-mediated FOXO3 phosphorylation and subsequent ubiquitin-proteasome degradation. Our findings illustrated the potential mechanisms by which Sinularin induced cell apoptosis and Sinularin may be applied as a therapeutic agent for human prostate cancer.


Asunto(s)
Proteínas Reguladoras de la Apoptosis , Diterpenos , Compuestos Heterocíclicos con 3 Anillos , Neoplasias de la Próstata , Humanos , Masculino , Apoptosis , Proteínas Reguladoras de la Apoptosis/metabolismo , Línea Celular Tumoral , Proteína Forkhead Box O3 , Próstata/metabolismo , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/metabolismo , Complejo de la Endopetidasa Proteasomal , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ubiquitinas/metabolismo
7.
Nat Commun ; 14(1): 7441, 2023 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-37978190

RESUMEN

Interferon-gamma (IFN-γ) signaling is necessary for the proinflammatory activation of macrophages but IFN-γ-independent pathways, for which the initiating stimuli and downstream mechanisms are lesser known, also contribute. Here we identify, by high-content screening, SEPTIN2 (SEPT2) as a negative regulation of IFN-γ-independent macrophage autoactivation. Mechanistically, endoplasmic reticulum (ER) stress induces the expression of SEPT2, which balances the competition between acetylation and ubiquitination of heat shock protein 5 at position Lysine 327, thereby alleviating ER stress and constraining M1-like polarization and proinflammatory cytokine release. Disruption of this negative feedback regulation leads to the accumulation of unfolded proteins, resulting in accelerated M1-like polarization, excessive inflammation and tissue damage. Our study thus uncovers an IFN-γ-independent macrophage proinflammatory autoactivation pathway and suggests that SEPT2 may play a role in the prevention or resolution of inflammation during infection.


Asunto(s)
Interferón gamma , Activación de Macrófagos , Humanos , Interferón gamma/metabolismo , Macrófagos/metabolismo , Citocinas/metabolismo , Inflamación/metabolismo
8.
Appl Opt ; 62(28): 7455-7462, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37855514

RESUMEN

In long-distance oil pipelines, the abnormal flow state of the fluid in the pipeline can cause continuous water hammer effects, which can damage the pipeline and even cause leakage or collapse. Based on this phenomenon, this paper proposes a new, to the best of our knowledge, detection method based on sensing optical fiber and phase-sensitive optical time-domain reflectometry (φ-OTDR) system to solve the problem of continuous water hammer detection in long-distance pipelines. The method uses a non-invasive, low-cost, real-time approach to monitor pipeline wall deformation characteristics and assess flow-induced vibration (FIV) intensity by statistically distinguishing water hammer signals from normal vibration signals and calculating the peak-to-average ratio (PAR) of these signals. Experimental results show that the FIV status of different types of pipelines can be effectively monitored by calculating the PAR of water hammer signals and vibration signals. The measured PAR based on the φ-OTDR system has high consistency with the PAR variation trend of simulation results, the distributed fiber optic sensor is less affected by environmental factors, and its detection distance and anti-interference ability are better than those of high-precision commercial triaxial acceleration sensors.

9.
Int J Mol Sci ; 24(18)2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37762463

RESUMEN

Overconsumption of high-fat foods increases the risk of fatty liver disease (FLD) and liver cancer with long pathogenic cycles. It is also known that the intake of the chemical poison nitrosamine and its nanopreparations can promote the development of liver injuries, such as FLD, and hepatic fibrosis, and significantly shorten the formation time of the liver cancer cycle. The present work confirmed that the coexposure of a high-fat diet (HFD) and nano-diethylnitrosamine (nano-DEN) altered the tumor microenvironment and studied the effect of this coexposure on the progression of fatty liver malignant transformation into liver cancer. Gene transcriptomics and immunostaining were used to evaluate the tumor promotion effect of the coexposure in mice. After coexposure treatment, tumor nodules were obviously increased, and inflammation levels were elevated. The liver transcriptomics analysis showed that the expression levels of inflammatory, fatty, and fibrosis-related factors in the coexposed group were increased in comparison with the nano-DEN- and high-fat-alone groups. The Kyoto Encyclopedia of Genes and Genomes (KEGG) results showed that coexposure aggravated the high expression of genes related to the carcinomatous pathway and accelerated the formation of the tumor microenvironment. The immunohistochemical staining results showed that the coexposure significantly increased the abnormal changes in proteins related to inflammation, proliferation, aging, and hypoxia in mouse liver tissues. The coexposure of high fat and nano-DEN aggravated the process of steatosis and carcinogenesis. In conclusion, the habitual consumption of pickled foods containing nitrosamines in a daily HFD significantly increases the risk of liver pathology lesions progressing from FLD to liver cancer.

10.
Cell Host Microbe ; 31(7): 1170-1184.e7, 2023 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-37402373

RESUMEN

The historically dominant SARS-CoV-2 Delta variant and the currently dominant Omicron variants carry a T492I substitution within the non-structural protein 4 (NSP4). Based on in silico analyses, we hypothesized that the T492I mutation increases viral transmissibility and adaptability, which we confirmed with competition experiments in hamster and human airway tissue culture models. Furthermore, we showed that the T492I mutation increases the replication capacity and infectiveness of the virus and improves its ability to evade host immune responses. Mechanistically, the T492I mutation increases the cleavage efficiency of the viral main protease NSP5 by enhancing enzyme-substrate binding, which increases production of nearly all non-structural proteins processed by NSP5. Importantly, the T492I mutation suppresses viral-RNA-associated chemokine production in monocytic macrophages, which may contribute to the attenuated pathogenicity of Omicron variants. Our results highlight the importance of NSP4 adaptation in the evolutionary dynamics of SARS-CoV-2.


Asunto(s)
COVID-19 , Animales , Cricetinae , Humanos , SARS-CoV-2/genética , Evolución Biológica , Mutación , Glicoproteína de la Espiga del Coronavirus
11.
Opt Express ; 31(12): 19853-19866, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37381392

RESUMEN

In this paper, based on the compressed sensing theory and the orthogonal matching pursuit algorithm, we have designed a data compression scheme, taking the Space-Temporal graph, time domain curve, and its time-frequency spectrum of phase-sensitive optical time-domain reflectometer as the target signals. The compression rates of the three signals were 40%, 35%, and 20%, while the average reconstruction times were 0.74 s, 0.49 s, and 0.32 s. The reconstructed samples effectively retained the characteristic blocks, response pulses, and energy distribution that symbolize the presence of vibrations. The average correlation coefficients of the three kinds of reconstructed signals with the original samples were 0.88, 0.85, and 0.86, respectively, and then a series of quantitative metrics were designed to evaluate the reconstructing efficiency. We have utilized the neural network trained by the original data to identify the reconstructed samples with an accuracy of over 70%, indicating that the reconstructed samples accurately present the vibration characteristics.

12.
J Chromatogr Sci ; 2023 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-37070405

RESUMEN

Anlotinib and osimertinib are a class of tyrosine kinase inhibitors for the treatment of malignant tumor. The combination of anlotinib and osimertinib is currently used for treating non-small cell lung cancer (NSCLC) patients. This study aimed to develop a simple and rapid isotope-labeled UHPLC-MS/MS method for the simultaneous determination of anlotinib and osimertinib in human plasma. The analytes were extracted by protein precipitation with acetonitrile and were then separated on a Shim-pack GIST C18 column. The detection was performed on Shimadzu 8050 triple quadruple mass spectrometer in the positive electrospray ionization mode with multiple reaction monitoring. The precursor-to-product ion transitions were m/z 408.10→ 339.75, 500.25→ 72.20 and 413.50 â†’ 344.50 for anlotinib, osimertinib and D5-anlotinib, respectively. Validation is based on US Food and Drug Administration guidelines. The linearity ranges were 0.5-100 ng/mL for anlotinib and were 1-500 ng/mL for osimertinib with the correlation coefficients (r  2) ≥ 0.99. Accuracy and precision, matrix effect, extraction recovery and stability of anlotinib and osimertinib were acceptable after validation. The UHPLC-MS/MS method was successfully validated and was applied to monitor the concentration of anlotinib and osimertinib in NSCLC patients.

13.
Geriatr Nurs ; 51: 54-64, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36893611

RESUMEN

OBJECTIVE: The aim of this review was to evaluate the overall diagnostic performance of e-devices for detection of health problems in older adults at home. METHODS: A systematic review was conducted following the PRISMA-DTA guidelines. RESULTS: 31 studies were included with 24 studies included in meta-analysis. The included studies were divided into four categories according to the signals detected: physical activity (PA), vital signs (VS), electrocardiography (ECG) and other. The meta-analysis showed the pooled estimates of sensitivity and specificity were 0.94 and 0.98 respectively in the 'VS' group. The pooled sensitivity and specificity were 0.97 and 0.98 respectively in the 'ECG' group. CONCLUSIONS: All kinds of e-devices perform well in diagnosing the common health problems. While ECG-based health problems detection system is more reliable than VS-based ones. For sole signal detection system has limitation in diagnosing specific health problems, more researches should focus on developing new systems combined of multiple signals.


Asunto(s)
Ejercicio Físico , Humanos , Anciano , Sensibilidad y Especificidad
14.
Front Microbiol ; 14: 1115556, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36825088

RESUMEN

Cancer and microbial infections are significant worldwide health challenges. Numerous studies have demonstrated that bacteria may contribute to the emergence of cancer. In this review, we assemble bacterial species discovered in various cancers to describe their variety and specificity. The relationship between bacteria and macrophages in cancer is also highlighted, and we look for ample proof to establish a biological basis for bacterial-induced macrophage polarization. Finally, we quickly go over the potential roles of metabolites, cytokines, and microRNAs in the regulation of the tumor microenvironment by bacterially activated macrophages. The complexity of bacteria and macrophages in cancer will be revealed as we gain a better understanding of their pathogenic mechanisms, which will lead to new therapeutic approaches for both inflammatory illnesses and cancer.

15.
Clin Transl Med ; 13(1): e1153, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36639831

RESUMEN

BACKGROUND: The MYC oncoprotein, also known as the master regulator of genes, is a transcription factor that regulates numerous physiological processes, including cell cycle control, apoptosis, protein synthesis and cell adhesion, among others. MYC is overexpressed in approximately 70% of human cancers. Given its pervasive role in cancer biology, MYC down-regulation has become an attractive cancer treatment strategy. METHODS: The CRISPR/Cas9 method was used to produce KO cell models. Western blot was used to analyzed the expressions of MYC and TATA-binding proteinassociated factors 10 (TAF10) in cancer cells (MCF7, A549, HepG2 cells) Cell culture studies were performed to determine the mechanisms by which small molecules (Z363119456, Z363) affects MYC and TAF10 expressions and functions. Mouse studies were carried out to investigate the impact of Z363 regulation on tumor growth. RESULTS: Z363 activate Thyroid hormone Receptor-interacting Protein 12 (TRIP12), which phosphorylates MYC at Thr58, resulting in MYC ubiquitination and degradation and thereby regulating MYC target genes. Importantly, TRIP12 also induces TAF10 degradation, which reduces MYC protein levels. TRIP12, an E3 ligase, controls MYC levels both directly and indirectly by inhibiting MYC or TAF10 activity. CONCLUSIONS: In summary,these results demonstrate the anti-cancer properties of Z363, a small molecule that is co-regulated by TAF10 and MYC.


Asunto(s)
Neoplasias , Proteínas Proto-Oncogénicas c-myc , Factores Asociados con la Proteína de Unión a TATA , Ubiquitina-Proteína Ligasas , Animales , Humanos , Ratones , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Regulación de la Expresión Génica , Factores de Transcripción/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación/genética , Proteínas Proto-Oncogénicas c-myc/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , Factores Asociados con la Proteína de Unión a TATA/genética , Factores Asociados con la Proteína de Unión a TATA/metabolismo
16.
International Eye Science ; (12): 1973-1977, 2023.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-998474

RESUMEN

Glaucomatous optic neuropathy(GON)is the difficulty of glaucoma treatment. In recent years, a variety of theories have been put forward about the pathogenesis of GON, but none of them can explain the principle of optic neuropathy caused by all types of glaucoma, which makes the disease difficult to treat in clinical treatment and is not conducive to early intervention. The latest research found that the transient receptor potential channel vanillic acid subfamily 4(TRPV4)in the retina plays an important role in various pathogenesis of GON. This article will review TRPV4 and its role in the occurrence and development of GON in order to find a common “connection point” for the multiple mechanism theories of GON, which will contribute to further understanding and clinical treatment of the disease.

17.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-996820

RESUMEN

ObjectiveThis study analyzed the outcome indicators in randomized controlled trials (RCTs) on traditional Chinese medicine (TCM) treatment of vertigo, aiming to provide a reference for clinical trial protocol design and the establishment of core indicator sets for vertigo treatment. MethodCNKI, Wanfang, VIP, SinoMed, PubMed, Embase, and Web of Science were searched for the RCTs on TCM treatment of vertigo, and data extraction was conducted. ResultA total of 375 RCTs involving 33 593 patients were included, from which 482 outcome indicators were extracted, with a frequency of 2 715 and an average of seven outcome indicators used for each RCT. In addition, there were some differences in outcome indicators reported by different study groups. According to the functional properties, the reported outcome indicators were classified into nine domains: clinical symptoms and signs, TCM symptom efficacy, physical and chemical examinations, quality of life, mental health, safety events, patients’ satisfaction degree, long-term prognosis, and economic evaluation. The outcome indicators with higher frequency were clinical total effective rate, total TCM symptom score, occurrence of adverse reactions, dizziness handicap inventory (DHI) score, average flow velocity of the basilar artery, incidence of adverse reactions, average flow velocity of the left vertebral artery, average flow velocity of the right vertebral artery, plasma viscosity, and vertigo score. ConclusionThe outcome indicators reported by RCTs of TCM treatment of vertigo mainly have two problems: lack of unified standards and norms and insufficient attention to outcome indicators that can reflect the characteristics of TCM. The construction of the core indicator set for TCM treatment of vertigo should fully highlight the characteristic advantages of TCM and unify the standards and norms for the outcome indicators on this basis, so as to improve the quality of clinical research and the value of secondary research.

18.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-973703

RESUMEN

Information technology has become an important driver to facilitate higher education developments in the context of new medical sciences. A new “virtual-real combination” experimental teaching model was designed and created through integrating information technology with experimental teaching by Experimental Teaching Center of Basic Medical Sciences and Department of Pathogen Biology, Nanjing Medical University and was applied in Human Parasitology teaching, which achieved satisfactory teaching effectiveness. This new model showed effective to deepen the understanding of the basic human parasitology knowledge, improve the operative skills, and cultivate the moral literacy and comprehensive capability among medical students. This report presents the teaching protocols and implementation, teaching effectiveness and evaluation, and experiences of comprehensive schistosome experiments.

19.
Mikrochim Acta ; 189(11): 407, 2022 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-36198915

RESUMEN

Uniform and monodisperse quantum dot (QD)-encoded magnetic microbeads with Janus structure were produced in a microfluidic device via photopolymerization. UV light through a microscope objective was used to solidify the microbeads which showed sharp interfaces and excellent magnetic responses. QDs with different emission peaks (450 nm for blue and 640 nm for red) were mixed at different ratios to provide three spectral codes. The QD-encoded microbeads can be distinguished by analyzing their fluorescent images in HSV color space. After hydrolysis of the anhydride group in alkaline solution, protein was immobilized on microbeads via activation of carboxyl groups using (1-ethyl-3(3-dimethylaminoprophyl) carbodiimide/N-hydroxysuccinimide (EDC/NHS). A microhole array in polydimethylsiloxane (PDMS) substrates with a specific size was fabricated to trap individual microbeads in a single microhole. The combination of Janus-structured QD-encoded magnetic microbeads and microhole arrays facilitates both flexibility, binding kinetics, sensitivity for suspension assay, and fluorescence mapping analysis for conventional biochips, thus providing a novel platform for multiplex bioanalysis. The capability of this integration for multiplex immunoassays was verified using three kinds of IgG and their corresponding anti-IgG. A detection limit of 0.07 ng/mL was achieved for human IgG, indicating practical applications in various fields.


Asunto(s)
Puntos Cuánticos , Anhídridos , Carbodiimidas , Dimetilpolisiloxanos , Humanos , Inmunoensayo/métodos , Microfluídica/métodos , Microesferas
20.
ACS Appl Mater Interfaces ; 14(34): 39354-39363, 2022 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-35984869

RESUMEN

Heat dissipation is necessary for the safer operation of high-power electronic devices and high-capacity batteries. Thermal meta-materials can efficiently manipulate heat flow by molding natural materials into specific structures. In this study, we construct a three-dimensional-printed meta-material structure with efficient and deterministic heat conduction through combining the 2D boron nitride (BN) with nano-diamond (DM) bridging. A research of thermal conductivity and dielectric properties exhibits that the nanosized diamond-bridged and oriented 2D boron nitride endows efficient heat transfer and maintains low dielectric loss with low filler loading. The composites loaded with 19 wt% BN platelets and 1 wt% DM have the highest thermal conductivity of 3.687 W/(m·K) in the heat flow orientation, while the thermal conductivity is only 0.632 W/(m·K) in the vertical heading of heat flow. The thermal conductive networks with thermal meta-materials based on the structural characteristics have been designed to secure critical device components from the heat source and dissipate heat flow in a definite way. The infrared images show that the temperature difference of monitoring points in different directions on the BN-oriented composite substrate is 9 °C, which realizes the protection of the heat source and key components. This study shows the latent capacity of 3D-printed structured materials for critical device component protection and heat administration applications in electronic devices and electric equipment.

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