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1.
Cereb Cortex ; 34(6)2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38937078

RESUMO

Table tennis players have adaptive visual and sensorimotor networks, which are the key brain regions to acquire environmental information and generate motor output. This study examined 20 table tennis players and 21 control subjects through ultrahigh field 7 Tesla magnetic resonance imaging. First, we measured percentage amplitude of fluctuation across five different frequency bands and found that table tennis players had significantly lower percentage amplitude of fluctuation values than control subjects in 18 brain regions, suggesting enhanced stability of spontaneous brain fluctuation amplitudes in visual and sensorimotor networks. Functional connectional analyses revealed increased static functional connectivity between two sensorimotor nodes and other frontal-parietal regions among table tennis players. Additionally, these players displayed enhanced dynamic functional connectivity coupled with reduced static connectivity between five nodes processing visual and sensory information input, and other large-scale cross-regional areas. These findings highlight that table tennis players undergo neural adaptability through a dual mechanism, characterized by global stability in spontaneous brain fluctuation amplitudes and heightened flexibility in visual sensory networks. Our study offers novel insights into the mechanisms of neural adaptability in athletes, providing a foundation for future efforts to enhance cognitive functions in diverse populations, such as athletes, older adults, and individuals with cognitive impairments.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Adulto Jovem , Encéfalo/fisiologia , Encéfalo/diagnóstico por imagem , Feminino , Adulto , Tênis/fisiologia , Atletas , Mapeamento Encefálico/métodos , Rede Nervosa/fisiologia , Rede Nervosa/diagnóstico por imagem , Vias Neurais/fisiologia , Adaptação Fisiológica/fisiologia , Adolescente
2.
Environ Sci Technol ; 58(23): 10388-10397, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38828512

RESUMO

Selective catalytic reduction of nitrogen oxides (NOx) with ammonia (NH3-SCR) is an efficient NOx reduction strategy, while the denitrification (deNOx) catalysts suffer from serious deactivation due to the coexistence of multiple poisoning substances, such as alkali metal (e.g., K), SO2, etc., in industrial flue gases. It is essential to understand the interaction among various poisons and their effects on the deNOx process. Herein, the ZSM-5 zeolite-confined MnSmOx mixed (MnSmOx@ZSM-5) catalyst exhibited better deNOx performance after the poisoning of K, SO2, and/or K&SO2 than the MnSmOx and MnSmOx/ZSM-5 catalysts, the deNOx activity of which at high temperature (H-T) increased significantly (>90% NOx conversion in the range of 220-480 °C). It has been demonstrated that K would occupy both redox and acidic sites, which severely reduced the reactivity of MnSmOx/ZSM-5 catalysts. The most important, K element is preferentially deposited at -OH on the surface of ZSM-5 carrier due to the electrostatic attraction (-O-K). As for the K&SO2 poisoning catalyst, SO2 preferred to be combined with the surface-deposited K (-O-K-SO2ads) according to XPS and density functional theory (DFT) results, the poisoned active sites by K would be released. The K migration behavior was induced by SO2 over K-poisoned MnSmOx@ZSM-5 catalysts, and the balance of surface redox and acidic site was regulated, like a synergistic promoter, which led to K-poisoning buffering and activity recovery. This work contributes to the understanding of the self-detoxification interaction between alkali metals (e.g., K) and SO2 on deNOx catalysts and provides a novel strategy for the adaptive use of one poisoning substance to counter another for practical NOx reduction.


Assuntos
Zeolitas , Zeolitas/química , Catálise , Oxirredução , Óxidos de Nitrogênio/química , Óxidos/química , Amônia/química , Desnitrificação , Metais/química
3.
Anal Chem ; 95(4): 2504-2512, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36651128

RESUMO

The establishment and application of a generalizable three-dimensional (3D) tumor device for high-throughput screening plays an important role in drug discovery and cancer therapeutics. In this study, we introduce a facile microplatform for considerable 3D tumor generation and combinatorial drug screening evaluation. High fidelity of chip fabrication was achieved depending on the simple and well-improved microcontact printing. We demonstrated the high stability and repeatability of the established tumor-on-a-chip system for controllable and massive production of 3D tumors with high size uniformity. Importantly, we accomplished the screening-like chemotherapy investigation involving individual and combinatorial drugs and validated the high accessibility and applicability of the system in 3D tumor-based manipulation and analysis on a large scale. This achievement in tumor-on-a-chip has potential applications in plenty of biomedical fields such as tumor biology, pharmacology, and tissue microengineering. It offers an insight into the development of the popularized microplatform with easy-to-fabricate and easy-to-operate properties for cancer exploration and therapy.


Assuntos
Neoplasias , Humanos , Avaliação Pré-Clínica de Medicamentos/métodos , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Ensaios de Triagem em Larga Escala , Descoberta de Drogas , Impressão Tridimensional
4.
Acta Pharmacol Sin ; 44(6): 1191-1205, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36627345

RESUMO

UDP-glucose ceramide glucosyltransferase (UGCG) is the first key enzyme in glycosphingolipid (GSL) metabolism that produces glucosylceramide (GlcCer). Increased UGCG synthesis is associated with cell proliferation, invasion and multidrug resistance in human cancers. In this study we investigated the role of UGCG in the pathogenesis of hepatic fibrosis. We first found that UGCG was over-expressed in fibrotic livers and activated hepatic stellate cells (HSCs). In human HSC-LX2 cells, inhibition of UGCG with PDMP or knockdown of UGCG suppressed the expression of the biomarkers of HSC activation (α-SMA and collagen I). Furthermore, pretreatment with PDMP (40 µM) impaired lysosomal homeostasis and blocked the process of autophagy, leading to activation of retinoic acid signaling pathway and accumulation of lipid droplets. After exploring the structure and key catalytic residues of UGCG in the activation of HSCs, we conducted virtual screening, molecular interaction and molecular docking experiments, and demonstrated salvianolic acid B (SAB) from the traditional Chinese medicine Salvia miltiorrhiza as an UGCG inhibitor with an IC50 value of 159 µM. In CCl4-induced mouse liver fibrosis, intraperitoneal administration of SAB (30 mg · kg-1 · d-1, for 4 weeks) significantly alleviated hepatic fibrogenesis by inhibiting the activation of HSCs and collagen deposition. In addition, SAB displayed better anti-inflammatory effects in CCl4-induced liver fibrosis. These results suggest that UGCG may represent a therapeutic target for liver fibrosis; SAB could act as an inhibitor of UGCG, which is expected to be a candidate drug for the treatment of liver fibrosis.


Assuntos
Células Estreladas do Fígado , Cirrose Hepática , Camundongos , Humanos , Animais , Simulação de Acoplamento Molecular , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/metabolismo , Fígado/metabolismo , Colágeno Tipo I/metabolismo
5.
Inflamm Res ; 71(9): 1095-1108, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35816227

RESUMO

Endotoxin-induced acute lung injury (ALI) is a challenging life-threatening disease for which no specific therapy exists. Mitochondrial dysfunction is corroborated as hallmarks in sepsis which commonly disrupt mitochondria-centered cellular communication networks, especially mitonuclear crosstalk, where the ubiquitous cofactor nicotinamide adenine dinucleotide (NAD+) is essential for mitonuclear communication. Heme oxygenase-1 (HO-1) is critical for maintaining mitochondrial dynamic equilibrium and regulating endoplasmic reticulum (ER) and Golgi stress to alleviating acute lung injury. However, it is unclear whether HO-1 regulates NAD+-mediated mitonuclear communication to exert the endogenous protection during endotoxin-induced ALI. In this study, we observed HO-1 attenuated endotoxin-induced ALI by regulated NAD+ levels and NAD+ affected the mitonuclear communication, including mitonuclear protein imbalance and UPRmt to alleviate lung damage. We also found the protective effect of HO-1 depended on NAD+ and NAD+-mediated mitonuclear communication. Furtherly, the inhibition of the PGC1α/PPARγ signaling exacerbates the septic lung injury by reducing NAD+ levels and repressing the mitonuclear protein imbalance and UPRmt. Altogether, our study certified that HO-1 ameliorated endotoxin-induced acute lung injury by regulating NAD+ and NAD+-mediated mitonuclear communications through PGC1α/PPARγ pathway. The present study provided complementary evidence for the cytoprotective effect of HO-1 as a potential target for preventing and attenuating of endotoxin-induced ALI.


Assuntos
Lesão Pulmonar Aguda , Heme Oxigenase-1 , Lesão Pulmonar Aguda/metabolismo , Endotoxinas/toxicidade , Heme Oxigenase-1/metabolismo , Humanos , NAD/efeitos adversos , NAD/metabolismo , PPAR gama/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Transdução de Sinais
6.
Analyst ; 147(11): 2294-2316, 2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35506869

RESUMO

Single-cell manipulation and analysis is critical to the study of many fundamental biological processes and uncovering cellular heterogeneity, and presents the potential for extremely valuable applications in biomedical fields, including neuroscience, regenerative therapy, early diagnosis, and drug screening. The use of microfluidic technologies in single-cell manipulation and analysis is one of the most promising approaches and enables the creation of innovative conditions that are impractical or impossible to achieve using conventional methods. Herein, an overview of the technological development of single-cell droplet microfluidics is presented. The significant advantages of microfluidic droplet technology, the dynamic parameters affecting droplet production, and the geometric structures of microfluidic devices are emphasized. Furthermore, the progress to date in passive and active droplet generation methods based on microfluidics and various microfluidic tools for the production of single-cell droplets and hydrogel microspheres are summarized. Their key features, achievements, and limitations associated with single-cell droplet and hydrogel formation are discussed. The recent popularized applications of single-cell droplet microfluidics in biomedicine involving small-molecule detection, protein analysis, and drug screening and genetic analysis of single cells are explored too. Finally, the challenges that must be overcome to enable future applications in single-cell droplet microfluidics are highlighted.


Assuntos
Técnicas Analíticas Microfluídicas , Microfluídica , Hidrogéis , Microfluídica/métodos
7.
Org Biomol Chem ; 20(46): 9234-9240, 2022 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-36382715

RESUMO

A phthalimide probe (P1) possessing a hydroxylamine group on the benzene ring has been prepared for fluorescence sensing of copper ions. The detection is based on the reaction between hydroxylamine and copper ions, resulting in two fluorescent products through hydroxyl rearrangement and dehydroxylation reactions. P1 shows a specific and sensitive fluorescence response towards copper ions with a limit of detection (LOD) of 1.11 nM (N = 3). The copper impurities from the industrial sources of the "click" ligand (tris(benzyltriazolylmethyl)amine (TBTA)) have been successfully examined using P1. This is the first case to utilize the reaction between hydroxylamine and copper ions. More importantly, the copper mediated hydroxyl rearrangement reaction opens a way to prepare a new sort of excited state intramolecular proton transfer (ESIPT) dye with ultra-small size and bright green fluorescence under physiological conditions.


Assuntos
Cobre , Corantes Fluorescentes , Espectrometria de Fluorescência/métodos , Prótons , Hidroxilaminas
8.
Crit Care ; 26(1): 46, 2022 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-35172856

RESUMO

BACKGROUND: Previous cluster-randomized controlled trials evaluating the impact of implementing evidence-based guidelines for nutrition therapy in critical illness do not consistently demonstrate patient benefits. A large-scale, sufficiently powered study is therefore warranted to ascertain the effects of guideline implementation on patient-centered outcomes. METHODS: We conducted a multicenter, cluster-randomized, parallel-controlled trial in intensive care units (ICUs) across China. We developed an evidence-based feeding guideline. ICUs randomly allocated to the guideline group formed a local "intervention team", which actively implemented the guideline using standardized educational materials, a graphical feeding protocol, and live online education outreach meetings conducted by members of the study management committee. ICUs assigned to the control group remained unaware of the guideline content. All ICUs enrolled patients who were expected to stay in the ICU longer than seven days. The primary outcome was all-cause mortality within 28 days of enrollment. RESULTS: Forty-eight ICUs were randomized to the guideline group and 49 to the control group. From March 2018 to July 2019, the guideline ICUs enrolled 1399 patients, and the control ICUs enrolled 1373 patients. Implementation of the guideline resulted in significantly earlier EN initiation (1.20 vs. 1.55 mean days to initiation of EN; difference - 0.40 [95% CI - 0.71 to - 0.09]; P = 0.01) and delayed PN initiation (1.29 vs. 0.80 mean days to start of PN; difference 1.06 [95% CI 0.44 to 1.67]; P = 0.001). There was no significant difference in 28-day mortality (14.2% vs. 15.2%; difference - 1.6% [95% CI - 4.3% to 1.2%]; P = 0.42) between groups. CONCLUSIONS: In this large-scale, multicenter trial, active implementation of an evidence-based feeding guideline reduced the time to commencement of EN and overall PN use but did not translate to a reduction in mortality from critical illness. TRIAL REGISTRATION: ISRCTN, ISRCTN12233792 . Registered November 20th, 2017.


Assuntos
Estado Terminal , Apoio Nutricional , China , Estado Terminal/terapia , Humanos , Unidades de Terapia Intensiva , Fatores de Tempo
9.
Allergol Immunopathol (Madr) ; 50(3): 113-118, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35527664

RESUMO

BACKGROUND: Pneumonia is a continuous and widespread disease with higher incidence, the effects of it on human life can be fearful. Tricin has been demonstrated to take part in the progression and development of diseases. However, the function of Tricin and its related regulatory pathways remain unclear. This study was planned to investigate the effects of Tricin on severe pneumonia. METHODS: The cell viability was detected through CCK-8 assay. The TNF-α, IL-1ß and IL-6 levels were assessed through ELISA and RT-qPCR. The levels of MDA, SOD and GSH were tested through corresponding commercial kits. The protein expressions were examined through western blot. RESULTS: In our study, the lipopolysaccharide (LPS) was firstly used to stimulate cell model for severe pneumonia. We discovered that Tricin had no toxic effects on BEAS-2B cells and the decreased cell viability induced by LPS was relieved by a dose-dependent Tricin treatment. Additionally, through ELISA and RT-qPCR, it was uncovered that Tricin reduced the LPS-induced inflammation through regulating TNF-α, IL-1ß and IL-6. Furthermore, Tricin relieved LPS-induced oxidative stress through reducing MDA level and enhancing SOD and GSH levels. Finally, it was demonstrated that Tricin retarded LPS-activated AKT and MAPK pathways. CONCLUSION: Our findings revealed that Tricin attenuated the progression of LPS induced severe pneumonia through modulating AKT and MAPK signaling pathways. This discovery might afford one novel sight for the treatment of severe pneumonia.


Assuntos
Lipopolissacarídeos , Pneumonia , Células Epiteliais/metabolismo , Flavonoides , Humanos , Inflamação , Interleucina-6/metabolismo , Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/farmacologia , Sistema de Sinalização das MAP Quinases , Proteínas Proto-Oncogênicas c-akt/metabolismo , Superóxido Dismutase/metabolismo , Superóxido Dismutase/farmacologia , Fator de Necrose Tumoral alfa/metabolismo
10.
J Neuroinflammation ; 18(1): 230, 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34645472

RESUMO

BACKGROUND: Astrocytic glycogen works as an essential energy reserve for surrounding neurons and is reported to accumulate excessively during cerebral ischemia/reperfusion (I/R) injury. Our previous study found that accumulated glycogen mobilization exhibits a neuroprotective effect against I/R damage. In addition, ischemia could transform astrocytes into A1-like (toxic) and A2-like (protective) subtypes. However, the underlying mechanism behind accumulated glycogen mobilization-mediated neuroprotection in cerebral reperfusion injury and its relationship with the astrocytic A1/A2 paradigm is unknown. METHODS: Astrocytic glycogen phosphorylase, the rate-limiting enzyme in glycogen mobilization, was specifically overexpressed and knocked down in mice and in cultured astrocytes. The I/R injury was imitated using a middle cerebral artery occlusion/reperfusion model in mice and an oxygen-glucose deprivation/reoxygenation model in cultured cells. Alterations in A1-like and A2-like astrocytes and the expression of phosphorylated nuclear transcription factor-κB (NF-κB) and phosphorylated signal transducer and activator of transcription 3 (STAT3) were determined by RNA sequencing, immunofluorescence and immunoblotting. Metabolites, including glycogen, NADPH, glutathione and reactive oxygen species (ROS), were analyzed by biochemical analysis. RESULTS: Here, we observed that astrocytic glycogen mobilization inhibited A1-like astrocytes and enhanced A2-like astrocytes after reperfusion in an experimental ischemic stroke model in vivo and in vitro. In addition, glycogen mobilization could enhance the production of NADPH and glutathione by the pentose phosphate pathway (PPP) and reduce ROS levels during reperfusion. NF-κB inhibition and STAT3 activation caused by a decrease in ROS levels were responsible for glycogen mobilization-induced A1-like and A2-like astrocyte transformation after I/R. The astrocytic A1/A2 paradigm is closely correlated with glycogen mobilization-mediated neuroprotection in cerebral reperfusion injury. CONCLUSIONS: Our data suggest that ROS-mediated NF-κB inhibition and STAT3 activation are the key pathways for glycogen mobilization-induced neuroprotection and provide a promising metabolic target for brain reperfusion injury in ischemic stroke.


Assuntos
Astrócitos/metabolismo , Isquemia Encefálica/metabolismo , Glicogênio/metabolismo , AVC Isquêmico/metabolismo , Neuroproteção/fisiologia , Traumatismo por Reperfusão/metabolismo , Animais , Animais Recém-Nascidos , Astrócitos/patologia , Isquemia Encefálica/patologia , Isquemia Encefálica/prevenção & controle , Técnicas de Cocultura , Feminino , AVC Isquêmico/patologia , AVC Isquêmico/prevenção & controle , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Espécies Reativas de Oxigênio/metabolismo , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/prevenção & controle
11.
J Virol ; 94(17)2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32581104

RESUMO

Cap-independent translation initiation on picornavirus mRNAs is mediated by an internal ribosomal entry site (IRES) in the 5' untranslated region. The regulation of internal initiation requires the interaction of IRES-transacting factors (ITAFs) with the IRES. In this study, we identified a novel ITAF, heterogeneous nuclear ribonucleoprotein K (hnRNP K), which negatively regulates foot-and-mouth disease virus (FMDV) translation and viral replication. Further investigation revealed that the KH2 and KH3 domains of hnRNP K directly bind to domains II, III, and IV of the FMDV IRES, resulting in the inhibition of IRES-mediated translation by interfering with the recognition of another positive ITAF, polypyrimidine tract-binding protein (PTB). Conversely, hnRNP K-mediated inhibition was antagonized by the viral 3C protease through the cleavage of hnRNP K at the Glu-364 residue during FMDV infection. Interestingly, the N-terminal cleavage product, hnRNP K1-364, retained partial inhibitory effects on IRES activity, whereas the C-terminal cleavage product, hnRNP K364-465, became a positive regulator of FMDV replication. Our findings expand the current understanding of virus-host interactions concerning viral recruitment and the modulation of ITAFs, providing new insights into translational control during viral infection.IMPORTANCE The translation of picornaviral genome RNA mediated by the internal ribosomal entry site (IRES) is a crucial step for virus infections. Virus-host interactions play a critical role in the regulation of IRES-dependent translation, but the regulatory mechanism remains largely unknown. In this study, we identified an ITAF, hnRNP K, that negatively regulates FMDV replication by inhibiting viral IRES-mediated translation. In addition, we describe a novel translational regulation mechanism involving the proteolytic cleavage of hnRNP K by FMDV protease 3C. The cleavage of hnRNP K yields two cleavage products with opposite functions: the cleavage product hnRNP K1-364 retains a partial inhibitory effect on IRES activity, and the cleavage product hnRNP K364-465 becomes a positive regulator of FMDV replication. Our findings shed light on the effect of a novel ITAF on the translational regulation of picornavirus and provide new insights into translational control during viral infection.


Assuntos
Cisteína Endopeptidases/metabolismo , Vírus da Febre Aftosa/fisiologia , Ribonucleoproteínas Nucleares Heterogêneas Grupo K/metabolismo , Sítios Internos de Entrada Ribossomal/fisiologia , Transativadores/metabolismo , Proteínas Virais/metabolismo , Replicação Viral/fisiologia , Proteases Virais 3C , Animais , Linhagem Celular , Cricetinae , Vírus da Febre Aftosa/genética , Regulação Viral da Expressão Gênica , Células HEK293 , Humanos , Proteína de Ligação a Regiões Ricas em Polipirimidinas , RNA Mensageiro , Proteínas Virais/genética
12.
J Virol ; 94(16)2020 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-32493820

RESUMO

Foot-and-mouth disease (FMD), which is caused by FMD virus (FMDV), remains a major plague among cloven-hoofed animals worldwide, and its outbreak often has disastrous socioeconomic consequences. A live-attenuated FMDV vaccine will greatly facilitate the global control and eradication of FMD, but a safe and effective attenuated FMDV vaccine has not yet been successfully developed. Here, we found that the internal ribosome entry site (IRES) element in the viral genome is a critical virulence determinant of FMDV, and a nucleotide substitution of cytosine (C) for guanine (G) at position 351 of the IRES endows FMDV with temperature-sensitive and attenuation (ts&att) phenotypes. Furthermore, we demonstrated that the C351G mutation of IRES causes a temperature-dependent translation defect by impairing its binding to cellular pyrimidine tract-binding protein (PTB), resulting in the ts&att phenotypes of FMDV. Natural hosts inoculated with viruses carrying the IRES C351G mutation showed no clinical signs, viremia, virus excretion, or viral transmission but still produced a potent neutralizing antibody response that provided complete protection. Importantly, the IRES C351G mutation is a universal determinant of the ts&att phenotypes of different FMDV strains, and the C351G mutant was incapable of reversion to virulence during in vitro and in vivo passages. Collectively, our findings suggested that manipulation of the IRES, especially its C351G mutation, may serve as a feasible strategy to develop live-attenuated FMDV vaccines.IMPORTANCE The World Organization for Animal Health has called for global control and eradication of foot-and-mouth disease (FMD), the most economically and socially devastating disease affecting animal husbandry worldwide. Live-attenuated vaccines are considered the most effective strategy for prevention, control, and eradication of infectious diseases due to their capacity to induce potent and long-lasting protective immunity. However, efforts to develop FMD virus (FMDV) live-attenuated vaccines have achieved only limited success. Here, by structure-function study of the FMDV internal ribosome entry site (IRES), we find that the C351 mutation of the IRES confers FMDV with an ideal temperature-sensitive attenuation phenotype by decreasing its interaction with cellular pyrimidine tract-binding protein (PTB) to cause IRES-mediated temperature-dependent translation defects. The temperature-sensitive attenuated strains generated by manipulation of the IRES address the challenges of FMDV attenuation differences among various livestock species and immunogenicity maintenance encountered previously, and this strategy can be applied to other viruses with an IRES to rationally design and develop live-attenuated vaccines.


Assuntos
Vírus da Febre Aftosa/genética , Sítios Internos de Entrada Ribossomal/genética , Animais , Anticorpos Neutralizantes/metabolismo , Bovinos , Feminino , Febre Aftosa/virologia , Vírus da Febre Aftosa/metabolismo , Vírus da Febre Aftosa/patogenicidade , Regulação Viral da Expressão Gênica/genética , Sítios Internos de Entrada Ribossomal/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Mutação/genética , Ribossomos/genética , Suínos , Vacinas Atenuadas , Virulência/genética , Replicação Viral/genética
13.
Analyst ; 146(13): 4303-4313, 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34105525

RESUMO

Microengineering technology involving microfabrication, micropatterning and microfluidics enables promising advances in single cell manipulation and analysis. Herein, we describe a parallel, large-scale, and temporal investigation of diverse single cell activities and response dynamics using a facile-assembled microwell array chip with a microfluidics-molded microporous membrane. We demonstrated that the versatility with respect to geometrical homogeneity and diversity of microporous membrane fabrication, as well as the stability, repeatability, and reproducibility rely on the well-improved molding. Serial and practical operations including controllable single cell trapping, array-like culture or chemical stimulation, and temporal monitoring can be smoothly completed in the chip. We confirmed that the microwell array chip allowed an efficient construction of a single cell array. Using the cell array, on-chip detection of single cell behaviours under various culture and drug therapy conditions to explore phenotypic heterogeneity was achieved in massive and dynamic manners. These achievements provide a facile and reliable methodology for fabricating microporous membranes with precise control and for developing universal microplatforms to perform robust manipulation and versatile analysis of single cells. This work also offers an insight into the development of easy to fabricate/use and market-oriented microsystems for single cell research, pharmaceutical development, and high-throughput screening.


Assuntos
Ensaios de Triagem em Larga Escala , Microfluídica , Análise de Sequência com Séries de Oligonucleotídeos , Reprodutibilidade dos Testes
14.
Analyst ; 146(2): 454-462, 2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33491017

RESUMO

Neuronal cell microengineering involving micropatterning and polydimethylsiloxane (PDMS) microfluidics enables promising advances in microscale neuron control. However, a facile methodology for the precise and effective manipulation of neurons on a cell-repellent PDMS substrate remains challenging. Herein, a simple and straightforward strategy for neuronal cell patterning and neuronal network construction on PDMS based on microfluidics-assisted modification of functionalized Pluronic is described. The cell patterning process simply involves a one-step microfluidic modification and routine in vitro culture. It is demonstrated that multiple types of neuronal cell arrangements with various spatial profiles can be conveniently produced using this patterning tool. The precise control of neuronal cells with high patterning fidelity up to single cell resolution, as well as high adhesion and differentiation, is achieved too. Furthermore, neuronal network construction using the respective cell population and single cell patterning prove to be applicable. This achievement provides a convenient and feasible methodology for engineering neuronal cells on PDMS substrates, which will be useful for applications in many neuron-related microscale analytical research fields, including cell engineering, neurobiology, neuropharmacology, and neuronal sensing.


Assuntos
Engenharia Celular/instrumentação , Dimetilpolisiloxanos/química , Dimetilpolisiloxanos/farmacologia , Dispositivos Lab-On-A-Chip , Rede Nervosa/citologia , Neurônios/citologia , Poloxâmero/química , Animais , Axônios/efeitos dos fármacos , Axônios/metabolismo , Dendritos/efeitos dos fármacos , Dendritos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos , Imagem Óptica
15.
Nanotechnology ; 32(21)2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33601355

RESUMO

Flexible and stretchable sensors are emerging and promising wearable devices for motion monitoring. Manufacturing a flexible and stretchable strain sensor with desirable electromechanical performance and excellent skin compatibility plays an essential role in building a smart wearable system. In this paper, a graphene-coated silk-spandex (GCSS) fabric strain sensor is prepared by reducing graphene oxide. The sensor functions as a result of conductive fiber extending and woven structure deforming. The conductive fabric can be stretched towards 60% with high sensitivity, and its performance remains constant after a 1000-cycle test. Based on its superior performance, the GCSS is successfully employed to detect full-range human movement and provide data for deep learning-based gesture recognition. This work offers a desirable method to fabricate low-cost strain sensors for industrial applications such as human movement detection and advanced information science.


Assuntos
Grafite/química , Monitorização Fisiológica/instrumentação , Poliuretanos/química , Seda/química , Têxteis , Materiais Biocompatíveis , Condutividade Elétrica , Humanos , Movimento (Física) , Movimento , Estresse Mecânico , Dispositivos Eletrônicos Vestíveis
16.
Anal Chem ; 92(10): 7200-7208, 2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32233451

RESUMO

The health impact of environmental pollution involving an increase in human diseases has been subject to extensive study in recent decades. The methodology in biomimetic investigation of these pathophysiologic events is still in progress to uncover the gaps in knowledge associated with pollution and its influences on health. Herein, we describe a comprehensive evaluation of environmental pollutant-caused lung inflammation and injury using a microfluidic pulmonary alveolus platform with alveolar-capillary interfaces. We performed a microfluidic three-dimensional coculture with physiological microenvironment simulation at microscale control and demonstrated a reliable reconstruction of tissue layers including alveolar epithelium and microvascular endothelium with typical mechanical, structural, and junctional integrity, as well as viability. On-chip detection and analysis of pulmonary alveolus responses focusing on various inflammatory and injurious dynamics to the respective pollutant stimulations were achieved in the coculture-based microfluidic pulmonary alveolus model, in comparison with common on-chip monoculture and off-chip culture tools. We confirmed the synergistic effects of the epithelial and endothelial interfaces on the stimuli resistance and verified the importance of creating complex tissue microenvironments in vitro to explore pollution-involved human pathology. We believe the microfluidic approach presents great promise in environmental monitoring, drug discovery, and tissue engineering.


Assuntos
Benzopirenos/efeitos adversos , Poluentes Ambientais/efeitos adversos , Técnicas Analíticas Microfluídicas , Nicotina/efeitos adversos , Pneumonia/induzido quimicamente , Alvéolos Pulmonares/efeitos dos fármacos , Benzopirenos/química , Células Cultivadas , Técnicas de Cocultura , Citocinas/análise , Citocinas/metabolismo , Poluentes Ambientais/química , Humanos , Microscopia Confocal , Estrutura Molecular , Nicotina/química , Pneumonia/metabolismo , Pneumonia/patologia , Alvéolos Pulmonares/metabolismo , Alvéolos Pulmonares/patologia , Espécies Reativas de Oxigênio/metabolismo
17.
Biotechnol Bioeng ; 117(4): 1092-1100, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31868229

RESUMO

Three-dimensional (3D) tumor has been considered as the best in vitro model for cancer research. In recent years, various methods have been developed to controllable prepare multisize 3D tumors. Nonetheless, reported technologies are still problematic and difficult to produce 3D tumors with highly uniform size and cell content. Here, a novel and simple microsphere-based mold approach is proposed to rapidly fabricate spherical microwell arrays for multisize 3D tumors formation, culture, and recovery. Larger amounts of HepG2 3D tumors with excellent quality and uniformity can be efficiently generated using this method. In addition, the tumor size can also be simply controlled by adjusting the diameter of the microwell arrays. All experimental results indicated that the proposed method offers a promising platform to generate and recover highly controlled multisize 3D tumors for various cell-based biomedical research.


Assuntos
Técnicas de Cultura de Células/instrumentação , Microesferas , Análise Serial de Tecidos/instrumentação , Antineoplásicos/farmacologia , Técnicas de Cultura de Células/métodos , Sobrevivência Celular/efeitos dos fármacos , Desenho de Equipamento , Células Hep G2 , Humanos , Impressão Tridimensional , Análise Serial de Tecidos/métodos
18.
Analyst ; 145(20): 6447-6455, 2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-33043931

RESUMO

The development of a microplatform with multifunctional integration allowing the dynamic and high-throughput exploration of three-dimensional (3D) cultures is promising for biomedical research. Here, we introduce an integrated microfluidic 3D tumor system with pneumatic manipulation and chemical gradient generation to investigate anticancer therapy in a parallel, controllable, dynamic, and high-throughput manner. The stability of the microfluidic system to realize precise and long-term chemical gradient production was developed. Serial manipulations including active cell trapping, array-like tumor self-assembly and formation, reliable gradient generation, parallel multi-concentration drug stimulation, and real-time tumor analysis were achieved in a single microfluidic device. The microfluidic platform was demonstrated to be stable for high-throughput cell trapping and 3D tumor formation with uniform quantities. On-chip analysis of phenotypic tumor responses to diverse chemotherapies with different concentrations can be conducted in this device. The microfluidic advancement holds great potential for applications in the development of high-performance and multi-functional biomimetic tumor systems and in the fields of cancer research and pharmaceutical development.


Assuntos
Técnicas Analíticas Microfluídicas , Microfluídica , Linhagem Celular Tumoral , Dispositivos Lab-On-A-Chip
19.
Clin Lab ; 66(8)2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32776759

RESUMO

BACKGROUND: The current study aims to observe the expression of hsa_circ_0141720 in the serum of patients with acute cerebral infarction (ACI) and to explore its clinical value in the diagnosis of ACI. METHODS: Eighty patients with ACI within the previous 48 hours were selected, and 30 healthy persons in the same period were selected as the control. Microarray analysis was performed to evaluate the changes of circRNA profiles, and RT-PCR was used to validate the findings. Pearson's correlation assay was performed to analyze the correlation between the level of hsa_circ_0141720 and other clinical indicators. RESULTS: Microarray analysis identified eight differentially expressed cirRNAs in the serum of ACI patients. RT-PCR validated that the expression of hsa_circ_0141720 in serum of ACI patients was increased the most. Hence, we mainly focused on hsa_circ_0141720 in the following study. ROC curve analysis showed that when the cutoff value for serum hsa_circ_0141720 was 2.03, the sensitivity and specificity were 89.7% and 95.6%, respectively. Further study showed that enhanced hsa_circ_0141720 expression was positively correlated with the National Institutes of Health Stroke Scale (NIHSS) scores and infarct volume of ACI patients. Moreover, upregulation of hsa_circ_0141720 was also positively correlated with increased expression of serum interleukin 6 (IL-6) and plasma high-sensitivity C relative protein (hs-CRP) in patients with ACI. CONCLUSIONS: In summary, enhanced expression of hsa_circ_0141720 in the serum of patients with ACI was related to the severity of the disease and it may be used as a new serological index for the diagnosis of ACI.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/genética , Humanos , RNA Circular , Curva ROC , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/genética
20.
J Cell Physiol ; 234(7): 10566-10575, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30565685

RESUMO

Metastatic melanoma accounts for 60% of death for skin cancer. Although great efforts have been made to treat the disease, effective drugs against metastatic melanoma still lack at the clinical setting. In the current study, we found that lycorine, a small molecule of isoquinoline alkaloid, significantly suppressed melanoma cell migration and invasion in vitro, and decreased the metastasis of melanoma cells to lung tissues in tumor-bearing mice, resulting in significant prolongation of the survival of the mice without obvious toxicity. Molecular mechanistic studies revealed that lycorine significantly reduced intracellular levels of ß-catenin protein through degradation of the protein via the ubiquitin-proteasome pathway, and decreased the expression of ß-catenin downstream prometastatic matrix metallopeptidase 9 and Axin2 genes. Collectively, our findings support the notion that targeting the oncogenic ß-catenin by lycorine is a new option to inhibit melanoma cell metastasis, providing a good drug candidate potential for development novel therapeutics against metastatic melanoma.


Assuntos
Alcaloides de Amaryllidaceae/farmacologia , Metaloproteinase 9 da Matriz/genética , Melanoma/tratamento farmacológico , Fenantridinas/farmacologia , beta Catenina/genética , Animais , Apoptose/efeitos dos fármacos , Proteína Axina/genética , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Humanos , Melanoma/genética , Melanoma/patologia , Camundongos , Metástase Neoplásica , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
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