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1.
Biophys J ; 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38532626

RESUMO

T cells coordinate intercellular communication through the meticulous regulation of cytokine secretion. Direct visualization of vesicular transport and intracellular distribution of cytokines provides valuable insights into the temporal and spatial mechanisms involved in regulation. Employing Jurkat E6-1 T cells and interleukin-2 (IL-2) as a model system, we investigated vesicular dynamics using single-particle tracking and the nanoscale distribution of intracellular IL-2 in fixed T cells using superresolution microscopy. Live-cell imaging revealed that in vitro activation resulted in increased vesicular dynamics. Direct stochastic optical reconstruction microscopy and 3D structured illumination microscopy revealed nanoscale clustering of IL-2. In vitro activation correlated with spatial accumulation of IL-2 nanoclusters into more pronounced and elongated clusters. These observations provide visual evidence that accelerated vesicular transport and spatial concatenation of IL-2 clusters at the nanoscale may constitute a potential mechanism for modulating cytokine release by Jurkat T cells.

2.
Nano Lett ; 22(10): 4020-4027, 2022 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-35499493

RESUMO

Dendritic cells (DCs) can infiltrate tight junctions of the epithelium to collect remote antigens during immune surveillance. While elongated membrane structures represent a plausible structure to perform this task, their functional mechanisms remain elusive owing to the lack of high-resolution characterizations in live DCs. Here, we developed fluorescent artificial antigens (FAAs) based on quantum dots coated with polyacrylic acid. Single-particle tracking of FAAs enables us to superresolve the membrane fiber network responsible for the antigen uptake. Using the DC2.4 cell line as a model system, we discovered the extensive membrane network approaching 200 µm in length with tunnel-like cavities about 150 nm in width. The membrane fiber network also contained heterogeneous circular migrasomes. Disconnecting the membrane network from the cell body decreased the intracellular FAA density. Our study enables mechanistic investigations of DC membrane networks and nanocarriers that target this mechanism.


Assuntos
Células Dendríticas , Pontos Quânticos , Antígenos , Linhagem Celular , Vacinas Sintéticas
3.
Sensors (Basel) ; 20(10)2020 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-32455906

RESUMO

A safe charging algorithm in wireless rechargeable sensor network ensures the charging efficiency and the electromagnetic radiation below the threshold. Compared with the current charging algorithms, the safe charging algorithm is more complicated due to the radiation constraint and the mobility of the chargers. A safe charging algorithm based on multiple mobile chargers is proposed in this paper to charge the sensor nodes with mobile chargers, in order to ensure the premise of radiation safety, multiple mobile chargers can effectively complete the network charging task. Firstly, this algorithm narrows the possible location of the sensor nodes by utilizing the charging time and antenna waveform. Secondly, the performance of non-partition charging algorithm which algorithm allow chargers to charge different sensors sets in a different cycle is evaluated against the one of partition charging which does not allow for charging different ones. The moving distance of the charger node will be reduced by 18%. It not only improves the safety level which is inversely proportional to electromagnetic radiation but also expands the application scope of the wireless sensor nodes.

4.
Mol Genet Genomics ; 294(2): 277-286, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30374564

RESUMO

Gene circuits are constructed to run complex logical operations for the precise regulation of biological metabolic processes. At present, the implementation of most genetic circuits is based on the regulatory mechanism of various circuit components, but we hope to realize complex logic gates through biological metabolic pathways of organisms. In this study, we matched the regulatory elements of different functional mechanisms to build a Boolean logic gate model by means of a dual-vector circuit. In Escherichia coli, we made 12 circuit logic gate modules and validated the functions of four of the logic gates, including "AND", "NAND", "OR" and "NOR" by the expression and analysis of a reporter gene. The inputs were converted into outputs by an intermediate product of the host metabolism. The results indicated that these logic gate circuits had the expected efficacy and regulatory characteristics. Our study provides new ideas for designing genetic circuits and precisely controlling metabolic pathways.


Assuntos
Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica/genética , Redes Reguladoras de Genes/genética , Redes e Vias Metabólicas/genética , Interações Hospedeiro-Patógeno/genética
5.
J Phys Chem Lett ; 14(15): 3621-3626, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37023397

RESUMO

Quantum dot (QD)-organic dye couple chromophores are topical due to their applications in biology, catalysis, and energy. The maximization of energy transfer efficiency can be guided by the underlying Förster or Dexter mechanisms; however, the impact of fluorescence intermittency must also be considered. Here we demonstrate that the average ⟨ton⟩ and ⟨toff⟩ times of dye acceptors in coupled QD-dye chromophores are substantially affected by the donors' blinking behavior. With regard to biological imaging, this effect beneficially minimizes the photobleaching of the acceptor dye. The implications for alternative energy are less encouraging as the acceptors' capacity to store energy, using ⟨ton⟩/⟨toff⟩ as a metric, was reduced by as much as ∼95%. These detrimental effects can be mitigated by suppressing QD blinking via surface treatment. This study also demonstrates several instances of the nonconformity of QD blinking dynamics to a power law distribution, as a robust examination of the off times reveals log-normal behavior that is consistent with the Albery model.


Assuntos
Pontos Quânticos , Transferência Ressonante de Energia de Fluorescência/métodos , Corantes/química , Pontos Quânticos/química
6.
Clin Case Rep ; 11(8): e7726, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37575464

RESUMO

We reported a case of a 7-year-old boy with pulmonary alveolar microlithiasis (PAM) and detected two novel compound heterozygous mutations of solute carrier family 34 member 2 (SLC34A2), EXON:2-6 duplication and c.1218 (EXON:11) C > A (p. Phe406Leu). His symptoms were nonspecific. Chest computed tomography (CCT) showed bronchiectasis, a mosaic feature, and extensive calcifications in both lungs. In addition, bronchoscopy showed bronchitis obliterans which has rarely been reported as a complication in the literature. This case aimed to explore the mechanism of PAM and emphasize the role of gene analysis in diagnosing rare pediatric diseases. Finally, we undertook a review of the current literature containing SLC34A2 gene mutations to update the gene mutation spectrum of PAM.

7.
Chin J Physiol ; 55(6): 428-34, 2012 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-23286451

RESUMO

Down-regulation of microglial activation represents a practical strategy for combating diverse brain disorders such as stroke and neurodegenerative diseases. In the present study, we showed evidence that isopropyl 3-(3, 4-dihydroxyphenyl)-2-hydroxypropanoate (IDHP), a new bioactive metabolite of Danshen (Salvia miltiorrhiza Bunge), exerted an anti-inflammatory effect in lipopolysaccharide (LPS)- induced microglia. Our data showed that IDHP significantly reduced the production of nitric oxide (NO), tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß) in LPS-induced BV-2 cells and rat primary microglia in a dose-dependent manner. IDHP also suppressed mRNA expression of LPSinduced inducible nitric oxide synthase (iNOS), TNF-α and IL-1ß. Moreover, IDHP significantly suppressed the production of reactive oxygen species (ROS), nuclear factor κB (NF-κB) translocation and DNA binding activity induced by LPS treatment in BV-2 cells. These findings indicated that IDHP might be of value in the treatment of various microglia-mediated neuroinflammatory diseases.


Assuntos
Microglia , Salvia miltiorrhiza , Animais , Interleucina-1beta , Lipopolissacarídeos/farmacologia , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo
8.
Nanoscale ; 13(10): 5519-5529, 2021 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-33688882

RESUMO

We report single-particle characterization of membrane-penetrating semiconductor quantum dots (QDs) in T cell lymphocytes. We functionalized water-soluble CdSe/CdZnS QDs with a cell-penetrating peptide composed of an Asp-Ser-Ser (DSS) repeat sequence. DSS and peptide-free control QDs displayed concentration-dependent internalization. Intensity profiles from single-particle imaging revealed a propensity of DSS-QDs to maintain a monomeric state in the T cell cytosol, whereas control QDs formed pronounced clusters. Single-particle tracking showed a direct correlation between individual QD clusters' mobility and aggregation state. A significant portion of control QDs colocalized with an endosome marker inside the T cells, while the percentage of DSS-QDs colocalized dropped to 9%. Endocytosis inhibition abrogated the internalization of control QDs, while DSS-QD internalization only mildly decreased, suggesting an alternative cell-entry mechanism. Using 3D single-particle tracking, we captured the rapid membrane-penetrating activity of a DSS-QD. The ability to characterize membrane penetrating activities in live T cells creates inroads for the optimization of gene therapy and drug delivery through the use of novel nanomaterials.


Assuntos
Preparações Farmacêuticas , Pontos Quânticos , Citosol , Imunoterapia , Linfócitos T
9.
Front Pharmacol ; 12: 755653, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34803698

RESUMO

Astragaloside IV (AS-IV) has been used to treat cardiovascular disease. However, whether AS-IV exerts a protective effect against hypertensive heart disease has not been investigated. This study aimed to investigate the antihypertensive and cardioprotective effects of AS-IV on L-NAME-induced hypertensive rats via network pharmacology and experimental pharmacology. The network pharmacology and bioinformatics analyses were performed to obtain the potential targets of AS-IV and hypertensive heart disease. The rat hypertension model was established by administrated 50 mg/kg/day of L-NAME for 5 weeks. Meanwhile, hypertension rats were intragastrically administrated with vehicle or AS-IV or fosinopril for 5 weeks. Cardiovascular parameters (systolic blood pressure, diastolic blood pressure, mean arterial pressure, heart rates, and body weight), cardiac function parameters (LVEDd, LVEDs, and fractional shortening), cardiac marker enzymes (creatine kinase, CK-MB, and lactate dehydrogenase), cardiac hypertrophy markers (atrial natriuretic peptide and brain natriuretic peptide), endothelial function biomarkers (nitric oxide and eNOS), inflammation biomarkers (IL-6 and TNF-α) and oxidative stress biomarkers (SOD, MDA, and GSH) were measured and cardiac tissue histology performed. Network pharmacological analysis screened the top 20 key genes in the treatment of hypertensive heart disease treated with AS-IV. Besides, AS-IV exerted a beneficial effect on cardiovascular and cardiac function parameters. Moreover, AS-IV alleviated cardiac hypertrophy via down-regulating the expression of ANP and BNP and improved histopathology changes of cardiac tissue. AS-IV improved endothelial function via the up-regulation of eNOS expression, alleviated oxidative stress via increasing antioxidant enzymes activities, and inhibited cardiac inflammation via down-regulating IL-6 and TNF-α expression. Our findings suggested that AS-IV is a potential therapeutic drug to improve L-NAME-induced hypertensive heart disease partly mediated via modulation of eNOS and oxidative stress.

10.
Biomed Opt Express ; 11(5): 2328-2338, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32499926

RESUMO

We introduce an accessible cell phone imaging method using small droplets of microscope immersion oil and consumer-grade oils. Oil droplets were more resistant to evaporation than water droplets, and they resolved cellular structures that were visible using a 20x/0.75 objective. We optically characterized the droplets using a cell phone screen and resolution target. We further obtained cellular resolution images of an onion epidermis and a zea stem cross-section sample. Our droplet-based method enables stable optical imaging for diagnostic and educational purposes without custom setups, specialized components, or manufacturing processes.

11.
Zhongguo Zhong Yao Za Zhi ; 34(8): 980-3, 2009 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-19639780

RESUMO

OBJECTIVE: To establish a method for the determination of ephedrine and pseudoephedrine in Herba Ephedrae and Maxing Shigan Tang by capillary zone electrophoresis. METHOD: The conditions of the experiment were optimized with a fused-silica capillary of 60 cm x 50 microm (50 cm effective length) in a running buffer of 50 mmol x L(-1) borax-20 mmol x L(-1) threonine (pH 9.27) and an applied voltage of 15 kV (room temperature). Samples were introduced by hydrodynamic injections (10 cm x 20 s)and determined with on-column UV monitoring at 210 nm. Phenobarbital was chosen as the internal standard. RESULT: Ephedrine and pseudoephedrine are separated successfully within 8 min. The linear responses covered the ranges from 21.3 to 213 mg x L(-1) (r = 0.9996) for ephedrine and from 8.4 to 84 mg x L(-1) (r = 0.9995) for pseudoephedrine. The detection limits (S/N = 3) of ephedrine and pseudoephedrine were shown to be 1.45 and 1.48 microg x mL(-1), respectively, The quantitation limits (S/N = 10) of ephedrine and pseudoephedrine were shown to be 4.81 and 4.93 mg x L(-1), respectively. The average recoveries for ephedrine and pseudoephedrine were 97.5% and 98.6% with RSD less than 5.0%. CONCLUSION: The method is simple, rapid, cost-effective and precise with satisfactory results.


Assuntos
Eletroforese Capilar/métodos , Ephedra sinica/química , Efedrina/análise , Plantas Medicinais/química , Pseudoefedrina/análise , Medicamentos de Ervas Chinesas , Reprodutibilidade dos Testes
12.
PLoS One ; 12(1): e0169560, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28060896

RESUMO

Parkinson's disease (PD) is a complex multi-system and age-related neurodegenerative disorder. The intervention targeting neuroinflammation in PD patients is one effective strategy to slow down or inhibit disease progression. Microglia-mediated inflammatory response plays an important role in Parkinson's, Alzheimer's and other cerebral diseases. Isobavachalcone is a main component of Chinese herb medicine Psoralea corylifolia, which function includes immunoregulation, anti-oxidation and the regulation of ß-amyloid (Aß42) deposited in hippocampus in Alzheimer's patients. Whether it has the therapeutic effect on Parkinson's disease, however, is unclear. In this study, we found that isobavachalcone could effectively remit Parkinson's disease induced by 1-methyl-4-phenyl-1,2,3,6- tetrahydropyridine (MPTP), prolong the residence time of mice on Rota-rod and alleviate the neuronal necrosis. It also inhibited the over-activation of microglia, and decreased the expression of IL-6 and IL-1ß in the brain of PD mice. In vitro, isobavachalcone could inhibit nuclear factor-kappaB (NF-κB) pathway through inhibiting the LPS-induced transfer of NF-κB subunit from cytoplasm to nucleus in BV-2 cells. Isobavachalcone decreased the LPS-induced oxidative stress and the expression of inflammatory cytokines, and provided a neuroprotective effect by antagonizing microglia-mediated inflammation. Our results indicated that isobavachalcone may be a candidated drug against Parkinson's disease with great clinical potential.


Assuntos
Chalconas/farmacologia , Microglia/imunologia , Microglia/metabolismo , NF-kappa B/metabolismo , Fármacos Neuroprotetores/farmacologia , Doença de Parkinson/etiologia , Doença de Parkinson/metabolismo , Transdução de Sinais/efeitos dos fármacos , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/efeitos adversos , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Biomarcadores , Linhagem Celular , Modelos Animais de Doenças , Mediadores da Inflamação , Interleucina-6/metabolismo , Masculino , Camundongos , Atividade Motora/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo
13.
Theranostics ; 7(6): 1749-1769, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28529649

RESUMO

The accumulations of excess lipids within liver and serum are defined as non-alcoholic fatty liver disease (NAFLD) and hyperlipemia respectively. Both of them are components of metabolic syndrome that greatly threaten human health. Here, a recombinant fusion protein (SAK-HV) effectively treated NAFLD and hyperlipemia in high-fat-fed ApoE-/- mice, quails and rats within just 14 days. Its triglyceride and cholesterol-lowering effects were significantly better than that of atorvastatin during the observation period. We explored the lipid-lowering mechanism of SAK-HV by the hepatic transcriptome analysis and serials of experiments both in vivo and in vitro. Unexpectedly, SAK-HV triggered a moderate energy and material-consuming liver proliferation to dramatically decrease the lipids from both serum and liver. We provided the first evidence that PGC-1α mediated the hepatic synthesis of female hormones during liver proliferation, and proposed the complement system-induced PGC-1α-estrogen axis via the novel STAT3-C/EBPß-PGC-1α pathway in liver as a new energy model for liver proliferation. In this model, PGC-1α ignited and fueled hepatocyte activation as an "igniter"; PGC-1α-induced estrogen augmented the energy supply of PGC-1α as an "ignition amplifier", then triggered the hepatocyte state transition from activation to proliferation as a "starter", causing triglyceride and cholesterol-lowering effects via PPARα-mediated fatty acid oxidation and LDLr-mediated cholesterol uptake, respectively. Collectively, the SAK-HV-triggered distinctive lipid-lowering strategy based on the new energy model of liver proliferation has potential as a novel short-period biotherapy against NAFLD and hyperlipemia.


Assuntos
Anticolesterolemiantes/administração & dosagem , Terapia Biológica/métodos , Hiperlipidemias/terapia , Hepatopatia Gordurosa não Alcoólica/terapia , Proteínas Recombinantes de Fusão/administração & dosagem , Animais , Modelos Animais de Doenças , Estrogênios/metabolismo , Hirudinas/administração & dosagem , Hirudinas/genética , Fígado/patologia , Metaloendopeptidases/administração & dosagem , Metaloendopeptidases/genética , Camundongos , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Codorniz , Ratos , Proteínas Recombinantes de Fusão/genética , Resultado do Tratamento
14.
J Ethnopharmacol ; 164: 247-55, 2015 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-25666429

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Radix Salviae Miltiorrhizae, known as Danshen, is a well-known traditional Chinese herb which has been used extensively for the treatment of various diseases, including cardiovascular and cerebrovascular disease and neurodegenerative diseases for thousands of years. Tanshinone I is one of major bioactive flavonoids of Radix Salviae Miltiorrhizae. Modulation of microglial over-reaction may represent a therapeutic target to alleviate the progression of neurodegenerative diseases. Here, we tested the effect of Tanshinone I on neuro-inflammation and whether it can provide neuroprotection through inhibition of neuro-inflammation. MATERIALS AND METHODS: The effects of Tanshinone I on the production and/or mRNA expression of pro-inflammatory and anti-inflammatory factors in lipopolysaccharide(LPS)-induced BV-2 microglia cells were tested by Griess reaction, enzyme-linked immunosorbent assay (Elisa) or real time polymerase chain reaction. Activation of nuclear factor κ B (NF-κB) was measured by the nuclear translocation p65 and DNA binding activity. A model of Parkinson׳s disease was established by treatment of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in C57BL/6 mice. The effect of Tanshinone I on the behavioral changes, dopamine and its metabolites levels, expression of tyrosine hydroxylase (TH) and IBA-1, production of cytokines in the midbrain were investigated by the rotarod test, high-performance liquid chromatography (HPLC)-ECD, immunohistochemistry and Elisa. 1-methyl-4-phenylpyridinium (MPP+) concentration was tested by HPLC. Liver toxicity was determined by biochemical assay and histochemistry. RESULTS: We found that the productions and/or expressions of several pro-inflammatory M1 factors such as nitric oxide (NO), tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß) and IL-6 were highly suppressed by Tanshinone I in LPS-induced microglia. Interestingly, it did not affect the enhancement of expression of some anti-inflammatory M2 microglia markers, including IL-10, IL-1 receptor antagonist (IL-1Ra) and Cox-2. But it could significantly inhibit LPS-induced granulocyte colony-stimulating factor (G-CSF) expression. Tanshinone I could also inhibit LPS-induced NF-κB activation in microglia. Furthermore, it improved motor functions, normalized striatal neurotransmitters, and provided dopaminergic neuronal protection in MPTP-intoxicated mice. In vivo results also indicated that Tanshinone I could modulate MPTP-induced microglial activation, attenuated the increase of TNF-α, reserved the increase of IL-10 concentrain of MPTP-intoxicated mice. Tanshinone I does not alter MPTP toxic metabolite (MPP+) concentration. Oral administration of Tanshinone I at 10mg/kg daily for 2 weeks did not show liver toxicity. CONCLUSIONS: Tanshinone I selectively suppressed pro-inflammatory M1 genes expression in activated microglia, interestingly, partially reserved anti-inflammatory M2 genes expression. It also could provide neuroprotection in a mouse model of Parkinson׳s disease. These data indicated that Tanshinone I could make the most of the beneficial side and minimize the detrimental side of activated microglia simultaneously, and provide neuroprotection by modulating the immune response of microglia.


Assuntos
Abietanos/farmacologia , Anti-Inflamatórios/farmacologia , Fármacos Neuroprotetores/farmacologia , Transtornos Parkinsonianos/metabolismo , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina , Abietanos/uso terapêutico , Animais , Anti-Inflamatórios/uso terapêutico , Formigas , Linhagem Celular , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/patologia , Ciclo-Oxigenase 1/genética , Ciclo-Oxigenase 2/genética , Citocinas/genética , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Proteínas de Membrana/genética , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , NF-kappa B , Fármacos Neuroprotetores/uso terapêutico , Óxido Nítrico/metabolismo , Transtornos Parkinsonianos/induzido quimicamente , Transtornos Parkinsonianos/tratamento farmacológico , Transtornos Parkinsonianos/patologia , Fitoterapia , Teste de Desempenho do Rota-Rod
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