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1.
ACS Appl Mater Interfaces ; 16(15): 18300-18310, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38574271

RESUMO

To tackle the proliferation of pathogenic microorganisms without relying on antibiotics, innovative materials boasting antimicrobial properties have been engineered. This study focuses on the development of graphene oxide/silver (GO/Ag) nanocomposites, derived from partially reduced graphene oxide adorned with silver nanoparticles. Various nanocomposites with different amounts of silver (GO/Ag-1, GO/Ag-2, GO/Ag-3, and GO/Ag-4) were synthesized, and their antibacterial efficacy was systematically studied. The silver nanoparticles were uniformly deposited on the partially reduced graphene oxide surface, exhibiting spherical morphologies with an average size of 25 nm. The nanocomposites displayed potent antibacterial properties against both gram-positive bacteria (S. aureus and B. subtilis) and gram-negative bacteria (E. coli and S. enterica) as confirmed by minimum inhibition concentration (MIC) studies and time-dependent experiments. The optimal MIC for Gram-positive bacteria was 62.5 µg/mL and for Gram-negative bacteria was 125 µg/mL for the GO/Ag nanocomposites. Bacterial cells that encountered the nanocomposite films exhibited significantly greater inhibitory effects compared to those exposed to conventional antibacterial materials. Furthermore, the cytotoxicity of these nanocomposites was assessed using human epithelial cells (HEC), revealing that GO/Ag-1 and GO/Ag-2 exhibited lower toxicity levels toward HEC and remained compatible even at higher dilution rates. This study underscores the potential of GO/Ag-based nanocomposites as versatile materials for antibacterial applications, particularly as biocompatible wound dressings, offering promising prospects for wound healing and infection control.


Assuntos
Grafite , Nanopartículas Metálicas , Nanocompostos , Humanos , Prata/farmacologia , Staphylococcus aureus , Escherichia coli , Óxidos/farmacologia , Antibacterianos/farmacologia , Grafite/farmacologia
2.
Cancer Discov ; 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38563585

RESUMO

Glioblastoma (GBM) exhibits profound metabolic plasticity for survival and therapeutic resistance, while the underlying mechanisms remain unclear. Here, we show that GBM stem cells (GSCs) reprogram the epigenetic landscape by producing substantial amounts of phosphocreatine (PCr). This production is attributed to the elevated transcription of brain-type creatine kinase (CKB), mediated by Zinc finger E-box binding homeobox 1 (ZEB1). PCr inhibits the poly-ubiquitination of the chromatin regulator bromodomain containing protein 2 (BRD2) by outcompeting the E3 ubiquitin ligase SPOP for BRD2 binding. Pharmacological disruption of PCr biosynthesis by cyclocreatine leads to BRD2 degradation and a decrease in its targets' transcription, which inhibits chromosome segregation and cell proliferation. Notably, cyclocreatine treatment significantly impedes tumor growth and sensitizes tumors to a BRD2 inhibitor in mouse GBM models without detectable side effects. These findings highlight that high production of PCr is a druggable metabolic feature of GBM and a promising therapeutic target for GBM treatment.

3.
Adv Mater ; : e2401151, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38558183

RESUMO

Natural material-based hydrogels are considered ideal candidates for constructing robust bio-interfaces due to their environmentally sustainable nature and biocompatibility. However, these hydrogels often encounter limitations such as weak mechanical strength, low water resistance, and poor ionic conductivity. Here, inspired by the role of natural moisturizing factor (NMF) in skin, a straightforward yet versatile strategy is proposed for fabricating all-natural ionic biogels that exhibit high resilience, ionic conductivity, resistance to dehydration, and complete degradability, without necessitating any chemical modification. A well-balanced combination of gelatin and sodium pyrrolidone carboxylic acid (an NMF compound) gives rise to a significant enhancement in the mechanical strength, ionic conductivity, and water retention capacity of the biogel compared to pure gelatin hydrogel. The biogel manifests temperature-controlled reversible fluid-gel transition properties attributed to the triple-helix junctions of gelatin, which enables in situ gelation on diverse substrates, thereby ensuring conformal contact and dynamic compliance with curved surfaces. Due to its salutary properties, the biogel can serve as an effective and biocompatible interface for high-quality and long-term electrophysiological signal recording. These findings provide a general and scalable approach for designing natural material-based hydrogels with tailored functionalities to meet diverse application needs.

4.
Cancer Lett ; 588: 216768, 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38453045

RESUMO

Hedgehog signaling is activated in response to liver injury, and modulates organogenesis. However, the role of non-canonical hedgehog activation via TGF-ß1/SMAD3 in hepatic carcinogenesis is poorly understood. TGF-ß1/SMAD3-mediated non-canonical activation was found in approximately half of GLI2-positive hepatocellular carcinoma (HCC), and two new GLI2 isoforms with transactivating activity were identified. Phospho-SMAD3 interacted with active GLI2 isoforms to transactivate downstream genes in modulation of stemness, epithelial-mesenchymal transition, chemo-resistance and metastasis in poorly-differentiated hepatoma cells. Non-canonical activation of hedgehog signaling was confirmed in a transgenic HBV-associated HCC mouse model. Inhibition of TGF-ß/SMAD3 signaling reduced lung metastasis in a mouse in situ hepatic xenograft model. In another cohort of 55 HCC patients, subjects with high GLI2 expression had a shorter disease-free survival than those with low expression. Moreover, co-positivity of GLI2 with SMAD3 was observed in 87.5% of relapsed HCC patients with high GLI2 expression, indicating an increased risk of post-resection recurrence of HCC. The findings underscore that suppressing the non-canonical hedgehog signaling pathway may confer a potential strategy in the treatment of HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Humanos , Camundongos , Carcinoma Hepatocelular/patologia , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Neoplasias Hepáticas/patologia , Camundongos Transgênicos , Proteínas Nucleares/metabolismo , Transdução de Sinais , Proteína Smad3/genética , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Proteína Gli2 com Dedos de Zinco/genética , Proteína Gli2 com Dedos de Zinco/metabolismo
5.
Medicine (Baltimore) ; 103(8): e37206, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38394493

RESUMO

Several studies have reported that antioxidants exert both preventive and inhibitory effects against tumors. However, their causal effects on small-cell lung cancer (SCLC) remain controversial. Herein, we explored the causal effects of 6 antioxidants on SCLC by combining a genome-wide association study database and the Mendelian randomization (MR) approach. We obtained antioxidant genetic variance data for 6 exposure factors: carotene, vitamin A (retinol), selenium, zinc, vitamin C, and vitamin E, from the genome-wide association study database. The instrumental variables for exposure factors and SCLC outcomes were integrated by screening instrumental variables and merging data. Two-sample MR was used to analyze the causal relationship between exposure and outcomes. Finally, we examined the heterogeneity and horizontal pleiotropy of the MR analysis by performing multiple sensitivity analyses. We found a causal relationship between carotene and SCLC using two-sample MR analysis and sensitivity analysis (P = .02; odds ratio = 0.73; 95% confidence interval: 0.55-0.95). In contrast, there was no causal relationship between other examined antioxidants and SCLC. We found that diet-derived circulating antioxidants could afford protection against SCLC, and carotene is the causal protective factor against SCLC.


Assuntos
Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Humanos , Antioxidantes , Estudo de Associação Genômica Ampla , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/prevenção & controle , Dieta , Carcinoma de Pequenas Células do Pulmão/genética , Vitamina A , Carotenoides , Análise da Randomização Mendeliana
6.
Int J Dermatol ; 63(2): 169-176, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38058233

RESUMO

BACKGROUND: Mycobacterium haemophilum has been increasingly found in severely immunocompromised patients but is scarcely reported in immunocompetent adults. METHODS: We systematically reviewed previous literature to identify studies on infection in immunocompetent adults. Articles reporting at least one case of M. haemophilum infection were included. We excluded articles involving patients who had immunosuppression-related diseases and routinely used glucocorticoids or immunosuppressants. We also reported a case of a young immunocompetent woman infected by M. haemophilum along the eyebrows, which was probably due to the use of an eyebrow pencil retrieved from a sink drain. RESULTS: Twelve qualifying articles reporting M. haemophilum infection in immunocompetent adults were identified. Among them, most cases report skin lesions along the eyebrows, and the remaining had cervicofacial lymphadenitis, lesions on the arm or fingers, inflammation in the eyeballs, or ulceration in the perineal region. Most cases were caused by tattoos, make-up, injury, or surgical operation. For diagnosis, specialized tissue culture sensitivity was roughly 75%, and polymerase chain reaction (PCR) test sensitivity was approximately 89%. Triple antibiotic therapy for 3 to 24 months, or surgical excision was effective in controlling infection. CONCLUSION: M. haemophilum infection should be considered if routine antibacterial and glucocorticoid treatments are ineffective against the disease, even in healthy adults. To definitively diagnose this infection, conditioned tissue culture or PCR testing is required. Treatment usually involves a combination of multiple antibiotics and, if necessary, surgical removal of infected tissue.


Assuntos
Linfadenite , Infecções por Mycobacterium , Mycobacterium haemophilum , Adulto , Feminino , Humanos , Antibacterianos/uso terapêutico , Linfadenite/diagnóstico , Infecções por Mycobacterium/diagnóstico , Infecções por Mycobacterium/tratamento farmacológico , Infecções por Mycobacterium/microbiologia , Inflamação
7.
Biochem Pharmacol ; 219: 115950, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38043718

RESUMO

Metabolic network intertwines with cancerous signaling and drug responses. Malonate is a prevailing metabolite in cancer and a competitive inhibitor of succinate dehydrogenase (SDH). Recent studies showed that malonate induced reactive oxygen species (ROS)-dependent apoptosis in neuroblastoma cells, but protected cells from ischemia-reperfusion injury. We here revealed that malonate differentially regulated cell death and survival in cancer cells. While high-dose malonate triggered ROS-dependent apoptosis, the low-dose malonate induced autophagy and conferred resistance to multiple chemotherapeutic agents. Mechanistically, our results showed that malonate increased p53 stability and transcriptionally up-regulated autophagy modulator DRAM (damage-regulated autophagy modulator), thus promoting autophagy. We further proved that autophagy is required for malonate-associated chemoresistance. Collectively, our findings suggest that malonate plays a double-edge function in cancer response to stressors, and highlights a pro-cancer impact of p53-induced autophagy in response to malonate.


Assuntos
Neoplasias , Proteína Supressora de Tumor p53 , Humanos , Espécies Reativas de Oxigênio/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Sobrevivência Celular , Resistencia a Medicamentos Antineoplásicos , Apoptose , Autofagia , Malonatos/farmacologia , Linhagem Celular Tumoral
8.
Biotechnol J ; 19(1): e2300519, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37997672

RESUMO

Metal enhanced fluorescence (MEF) is a phenomenon that increases fluorescence signal through placement of metal near a fluorophore. For biosensing applications, MEF-based biosensors are becoming increasingly popular as it enables highly sensitive detection of molecules, important for early diagnosis. The structure and size of the metal influence the optical properties through enhancing the fluorophore photostability and light absorption and emission. In recent years, many metal nanostructures have been fabricated and examined for their effectiveness in developing MEF-based biosensors. This review focuses on the latest applications of three-dimensional nanostructures and nano-patterned surfaces used to develop and improve fluorescence sensing via MEF. Current reviews mostly discussed the applications of two dimensional MEF and metal-nanoparticles-based MEF with a focus on fabrication of nanoparticles and metal substrates. In this article, we focused more on the effect of the metal nanostructure and size on MEF and then provided an in-depth summary of the performance of the state-of-the-art three dimensional MEF-based biosensors. While more work is needed to demonstrate applicability for complex samples, it is evident that with the use of metal nanoparticles and three dimensional nano-patterns, the assay sensitivity of fluorescence-based detection can be greatly improved, making it suitable for use in early disease diagnostics.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Nanoestruturas , Espectrometria de Fluorescência/métodos , Metais/química , Corantes Fluorescentes/química , Nanoestruturas/química , Técnicas Biossensoriais/métodos , Nanopartículas Metálicas/química
9.
Nutr Rev ; 82(3): 374-388, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-37604108

RESUMO

Front-of-package (FOP) labels have been adopted in many countries to battle the obesity pandemic and its serious health consequences by providing clearer and easier-to-understand nutrition and health information. The effectiveness of FOP labels has been generally confirmed, with some contextual and individual factors modifying their effectiveness. Existing theories (eg, the dual-process theory) and shifting priorities for self-control, provide some explanations for the FOP label effect. However, the cognitive and neural mechanisms underlying the processing of FOP labels remain unknown. Here, a new model, namely, the neural model of FOP label processing, has been proposed to fill this gap by providing an integrated account of FOP label processing while simultaneously considering multiple important situational and individual factors in the same framework. This neural model is built on the core eating network (ie, the ventral reward pathway and the dorsal control pathway) for food cue processing and actual food consumption. The new model explains how FOP labels may facilitate attention, influence the core eating network, and thus alter food choices. It also demonstrates how motivation may modify FOP label processing in 2 ways: affecting attention (the indirect way) and changing the process of evaluating the food (the direct way). It further explains how some contextual and individual factors (eg, ego depletion, time pressure, and health knowledge) influence the process. Thus, the neural model integrates evidence from behavioral, eye-tracking, and neuroimaging studies into a single, integrated account, deepening understanding of the cognitive and neural mechanisms of FOP label processing. This model might facilitate consensus on the most successful FOP label. Moreover, it could provide insights for consumers, food industries, and policy makers and encourage healthy eating behaviors.


Assuntos
Comportamento do Consumidor , Rotulagem de Alimentos , Humanos , Rotulagem de Alimentos/métodos , Alimentos , Preferências Alimentares/psicologia , Atenção , Comportamento de Escolha , Valor Nutritivo
10.
Anal Biochem ; 683: 115369, 2023 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-37914004

RESUMO

Microarrays are powerful tools for high-throughput bioassays that can extract information from tens of thousands of micro-spots consisting of biomolecules. This information is invaluable to many applications, such as drug discovery and disease diagnostics. Different applications of these microarrays need spots of different shapes, sizes, and chemistries to achieve their goals. Micro/nano-fabrication techniques are used to make microarrays with different feature structures and array densities for required assay procedures. Understanding these fabrication methods is essential to creating an effective microarray. The purpose of this article is to critically review fabrication methods used in recent microarray-based bioassay studies. We summarized commonly used microarray fabrication techniques and filled the gap in recent literature on relevant topics. We discussed recent examples of how microarrays were fabricated and used in a variety of bioassays. Specifically, we examined microarray printing, various microlithography techniques, and microfluidics-based microarray fabrication. We evaluated how their application shaped the fabrication methods and compared their performance based on different applications. In the end, we discussed current challenges and outlined potential future directions. This review addressed the gap in literature and provided important insights for choosing appropriate fabrication techniques towards different applications.


Assuntos
Bioensaio , Microfluídica , Análise em Microsséries
11.
Adv Sci (Weinh) ; 10(34): e2304668, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37870166

RESUMO

Positive computed tomography (CT) contrast nanoagent has significant applications in diagnosing tumors. However, the sensitive differentiation between hepatoma and normal liver tissue remains challenging. This challenge arises primarily because both normal liver and hepatoma tissues capture the nanoagent, resulting in similar positive CT contrasts. Here, a strategy for fusing positive and negative CT contrast nanoagent is proposed to detect hepatoma. A nanoagent Hf-MOF@AB@PVP initially generates a positive CT contrast signal of 120.3 HU in the liver. Subsequently, it can specifically respond to the acidic microenvironment of hepatoma to generate H2 , further achieving a negative contrast of -96.0 HU. More importantly, the relative position between the negative and positive signals area is helpful to determine the location of hepatoma and normal liver tissues. The distinct contrast difference of 216.3 HU and relative orientation between normal liver and tumor tissues are meaningful to sensitively distinguish hepatoma from normal liver tissue utilizing CT imaging.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Meios de Contraste , Microambiente Tumoral
12.
ACS Nano ; 17(14): 13872-13884, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37458394

RESUMO

"Structure subserves function" is one fundamental biological maxim, and so the biological membrane that delimits the regions primarily serves as the margin between life and death for individual cells. Here, an Oswald ripening mechanism-guided solvothermal method was proposed for the synthesis of uniform MnS nanocapsules assembled with metastable γ-MnS nanocrystals. Through designing the physicochemical properties, MnS nanocapsules would disaggregate into small γ-MnS nanocrystals in a tumor acidic environment, with the surface potential switched from negative to positive, thus showing conspicuous delivery performance. More significantly, the specific accumulation of Mn2+ in mitochondria was promoted due to the downregulation of mitochondrial calcium uptake 1 (MICU1) by the formed H2S, thus leading to serious mitochondrial Mn-poisoning for membrane permeability increase and then tumor apoptosis. This study provides a synthesis strategy of metal sulfide nanocapsules and encourages multidisciplinary researchers to focus on ion-cancer crosstalk for the development of an antitumor strategy.


Assuntos
Membranas Mitocondriais , Nanocápsulas , Membranas Mitocondriais/metabolismo , Mitocôndrias , Apoptose , Permeabilidade
13.
Behav Sci (Basel) ; 13(7)2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-37504020

RESUMO

In the context of online consumption, consumers are often faced with a decision between buying now or later. This study examines intertemporal choice by conducting two mixed experimental designs on a total of 206 college students to investigate the impact of combining sales volume and limited quantity on online consumption decisions. Experiment 1 revealed that under unlimited conditions, the same option with high sales volume was relatively more attractive and participants were more inclined to choose it, leading to a herding effect. However, under limited conditions, there was no scarcity effect. Experiment 2 built upon the findings of Experiment 1 and added dynamic change in sales volume. It was found that even with dynamic changes in sales volume, high sales volumes could still lead to a herding effect. In the case of unlimited conditions, dynamic changes in sales offset the effect of sales volume on intertemporal choice. Sales volume and limited quantity are important factors that influence consumers' purchasing decisions. Therefore, this study combines sales volume and limited quantity and adds dynamic changes in sales to explore individuals' intertemporal choices in online consumption situations. The findings of the study have significant implications for both merchants and consumers.

14.
Anal Chem ; 95(23): 9068-9075, 2023 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-37267452

RESUMO

Microarrays have been widely used for multiplexed bioassays. Fabrication of a conventional microarray typically requires a complex microarray spotter, using which nanoliter bioreagent (e.g., antibody and cells) droplets are delivered onto a glass slide. However, arraying a delicate bioreagent in nanoliter volumes could cause the loss of bioactivity and needs a complex microarray spotter. Further, mixing of different bioreagents in a multiplexed assay leads to cross-reactions, producing false positive signals that impair assay reproducibility and scalability. In this work, we propose a new microarray format, named "compartmentalized linker array (CLA)", that consists of pre-prepared storable microarrays of chemical linkers in microliter compartments. CLA can be used for binding and patterning bioreagents into microarrays by simply pipetting and incubating bioreagent solutions in compartments. Using commonly used aminosilane linker-based antibody microarray, we developed CLA and demonstrated its application for a multiplexed sandwich immunoassay measuring three cancer-related proteins. A "two-phase" blocking system was established for de-activating background regions on glass where no linker molecules are present. Storage conditions of the CLA chip were explored and demonstrated for long-term storage. In a multiplexed immunoassay, low pg/mL sensitivity was achieved for all the three proteins, comparable to those of conventional assays. Moreover, CLA can be potentially used for other applications beyond protein assays, making microarray technology transferrable and widely available for the biological and biomedical research community.


Assuntos
Análise Serial de Proteínas , Proteínas , Reprodutibilidade dos Testes , Análise em Microsséries , Imunoensaio , Anticorpos/química
15.
Adv Sci (Weinh) ; 10(23): e2300604, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37276385

RESUMO

Increased levels of circulating cell-free DNA (cfDNA) are associated with poor clinical outcomes in patients with acute kidney injury (AKI). Scavenging cfDNA by nanomaterials is regarded as a promising remedy for cfDNA-associated diseases, but a nanomaterial-based cfDNA scavenging strategy has not yet been reported for AKI treatment. Herein, polyglycerol-amine (PGA)-covered MoS2 nanosheets with suitable size are synthesized to bind negatively charged cfDNA in vitro, in vivo and ex vivo models. The nanosheets exhibit higher cfDNA binding capacity than polymer PGA and PGA-based nanospheres owing to the flexibility and crimpability of their 2D backbone. Moreover, with low cytotoxicity and mild protein adsorption, the nanosheets effectively reduced serum cfDNA levels and predominantly accumulated in the kidneys to inhibit the formation of neutrophil extracellular traps and renal inflammation, thereby alleviating both lipopolysaccharide and ischemia-reperfusion induced AKI in mice. Further, they decreased the serum cfDNA levels in samples from AKI patients. Thus, PGA-covered MoS2 nanosheets can serve as a potent cfDNA scavenger for treating AKI and other cfDNA-associated diseases. In addition, this work demonstrates the pivotal feature of a 2D sheet-like structure in the development of the cfDNA scavenger, which can provide a new insight into the future design of nanoplatforms for modulating inflammation.


Assuntos
Injúria Renal Aguda , Ácidos Nucleicos Livres , Camundongos , Animais , Molibdênio , Injúria Renal Aguda/tratamento farmacológico , Inflamação/complicações , Aminas
16.
Science ; 380(6648): 972-979, 2023 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-37262147

RESUMO

The suprachiasmatic nucleus (SCN) drives circadian clock coherence through intercellular coupling, which is resistant to environmental perturbations. We report that primary cilia are required for intercellular coupling among SCN neurons to maintain the robustness of the internal clock in mice. Cilia in neuromedin S-producing (NMS) neurons exhibit pronounced circadian rhythmicity in abundance and length. Genetic ablation of ciliogenesis in NMS neurons enabled a rapid phase shift of the internal clock under jet-lag conditions. The circadian rhythms of individual neurons in cilia-deficient SCN slices lost their coherence after external perturbations. Rhythmic cilia changes drive oscillations of Sonic Hedgehog (Shh) signaling and clock gene expression. Inactivation of Shh signaling in NMS neurons phenocopied the effects of cilia ablation. Thus, cilia-Shh signaling in the SCN aids intercellular coupling.


Assuntos
Cílios , Relógios Circadianos , Ritmo Circadiano , Proteínas Hedgehog , Neurônios do Núcleo Supraquiasmático , Animais , Camundongos , Cílios/metabolismo , Cílios/fisiologia , Relógios Circadianos/genética , Ritmo Circadiano/fisiologia , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Neurônios do Núcleo Supraquiasmático/fisiologia , Transdução de Sinais , Regulação da Expressão Gênica , Camundongos Transgênicos
17.
Cogn Neurodyn ; 17(2): 467-476, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37007203

RESUMO

In order to improve the modeling performance of Volterra sequence for nonlinear neural activity, in this paper, a new optimization algorithm is proposed to identify Volterra sequence parameters. Algorithm combines the advantages of particle swarm optimization (PSO) and genetic algorithm (GA) improve the performance of the identification of nonlinear model parameters from rapidity and accuracy. In the modeling experiments of neural signal data generated by the neural computing model and clinical neural data set in this paper, the proposed algorithm shows its excellent potential in nonlinear neural activity modeling. Compared with PSO and GA, the algorithm can achieve less identification error, and better balance the convergence speed and identification error. Further, we explore the influence of algorithm parameters on identification efficiency, which provides possible guiding significance for parameter setting in practical application of the algorithm.

18.
Mikrochim Acta ; 190(4): 144, 2023 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-36939899

RESUMO

Conventional cellular protein detection techniques such as immunocytochemistry and flow cytometry require abundant cells, posing multiple challenges, including difficulty and cost for obtaining enough cells and the potential for clogging the instrument when using flow cytometry. Also, it is challenging to conduct cellular protein imaging and quantification simultaneously from a single experiment. We present a novel 3D platform, which integrates highly biocompatible cell-entrapped alginate hydrogel droplet array with gold-nanoparticle (AuNP)-based metal enhanced fluorescence (MEF), to achieve simultaneous imaging and quantification of proteins in intact cells in a sensitive manner. Compared to 2D immunocytochemistry, this 3D system allows for a higher cell loading capacity per unit area; together with the MEF-based signal enhancement from the embedded AuNPs, sensitive protein quantification was realized. Furthermore, compared to flow cytometry, this platform allows for protein imaging from individual cells. Taking the detection of EpCAM protein in ovarian cancer cells as a model, we optimized the AuNP size and concentration for optimal fluorescent signals. The 5 nm AuNPs at 6.54 × 1013 particles/mL proved to be the most effective in signal enhancement, providing 2.4-fold higher signals compared to that without AuNPs and 6.4-fold higher signals than that of 2D immunocytochemistry. The number of cells required in our technology is 1-3 orders of magnitude smaller than that of conventional methods. This AuNP-embedded hydrogel platform combines the benefits of immunocytochemistry and flow cytometry, providing increased assay sensitivity while also allowing for qualitative analysis through imaging, suitable for protein determination in a variety of cells.


Assuntos
Hidrogéis , Nanopartículas Metálicas , Ouro , Fluorescência
20.
Ocul Immunol Inflamm ; : 1-6, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36888977

RESUMO

This report describes a case of idiopathic hypertrophic cranial pachymeningitis (IHCP) with scleritis and optic disc involvement. The patient was a 56-year-old woman with chief complaints of fever, headache, binocular pain, and redness. Biochemical and immunological indicators, cranial magnetic resonance imaging, and relevant ophthalmological examinations were employed for evaluation. Infectious and neoplastic causes were excluded. Typical meningeal thickening and enhancement on magnetic resonance imaging revealed IHCP. Diffuse hyperaemia and oedema of the conjunctiva and the T-shape sign on the B-scan suggested anterior and posterior scleritis, respectively. Abnormalities in fundus photography, optical coherence tomography, and visual field examination suggested optic disc involvement. After anti-infection and steroid therapy, the patient's temperature returned to normal and the symptoms of headache, binocular pain, and redness improved. Neurologists and ophthalmologists should consider the combination of IHCP with scleritis in their differential diagnosis when patients complain of headache accompanied by ocular pain and redness.

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