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1.
ACS Nano ; 18(8): 6612-6622, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38359901

RESUMO

To perform multiplex profiling of single cells and eliminate the risk of potential sample loss caused by centrifugation, we developed a microfluidic flow cytometry and mass spectrometry system (µCytoMS) to evaluate the drug uptake and induced protein expression at the single cell level. It involves a microfluidic chip for the alignment and purification of single cells followed by detection with laser-induced fluorescence (LIF) and inductively coupled plasma mass spectrometry (ICP-MS). Biofunctionalized nanoprobes (BioNPs), conjugating ∼3000 6-FAM-Sgc8 aptamers on a single gold nanoparticle (AuNP) (Kd = 0.23 nM), were engineered to selectively bind with protein tyrosine kinase 7 (PTK7) on target cells. PTK7 expression induced by oxaliplatin (OXA) uptake was assayed with LIF, while ICP-MS measurement of 195Pt revealed OXA uptake of the drug in individual cells, which provided further in-depth information about the drug in relation to PTK7 expression. At an ultralow flow of ∼0.043 dyn/cm2 (20 µL/min), the chip facilitates the extremely fast focusing of BioNPs labeled single cells without the need for centrifugal purification. It ensures multiplex profiling of single cells at a throughput speed of 500 cells/min as compared to 40 cells/min in previous studies. Using a machine learning algorithm to initially profile drug uptake and marker expression in tumor cell lines, µCytoMS was able to perform in situ profiling of the PTK7 response to the OXA at single-cell resolution for tests done on clinical samples from 10 breast cancer patients. It offers great potential for multiplex single-cell phenotypic analysis and clinical diagnosis.


Assuntos
Nanopartículas Metálicas , Microfluídica , Humanos , Citometria de Fluxo , Ouro , Biomarcadores , Espectrometria de Massas/métodos , Moléculas de Adesão Celular , Receptores Proteína Tirosina Quinases
2.
Anal Chem ; 95(35): 13297-13304, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37610312

RESUMO

A 2D flow cytometry platform, known as CytoLM Plus, was developed for multi-parameter single-cell analysis. Single particles or cells after hydrodynamic alignment in a microfluidic unit undergo first-dimension fluorescence and side scattering dual-channel optical detection. They were thereafter immediately directed to ICP-MS by connecting the microfluidic unit with a high-efficiency nebulizer to facilitate the second-dimension ICP-MS detection. Flow cytometry measurements of fluorescent microspheres evaluated the performance of CytoLM Plus for optical detection. 6434 fluorescence bursts were observed with a valid signal proportion as high as 99.7%. After signal unification and gating analysis, 6067 sets of single-particle signals were obtained with 6.6 and 6.2% deviations for fluorescence burst area and height, respectively. This is fairly comparable with that achieved by a commercial flow cytometer. Afterward, CytoLM Plus was evaluated by 2D flow cytometry measurement of Ag+-incubated and AO-stained MCF-7 cells. A program for 2D single-cell signal unification was developed based on the algorithm of screening in lag time window. In the present case, a lag time window of -4.2 ± 0.09 s was determined by cross-correlation analysis and two-parameter optimization, which efficiently unified the concurrent single-cell signals from fluorescence, side scattering, and ICP-MS. A total of 495 sets of concurrent 2D signals were screened out, and the statistical analysis of these single-cell signals ensured 2D multi-parameter single-cell analysis and data elucidation.


Assuntos
Algoritmos , Projetos de Pesquisa , Humanos , Corantes , Citometria de Fluxo , Análise de Célula Única
3.
Talanta ; 258: 124424, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36905790

RESUMO

Flow cytometry is among the most powerful tools for single-cell analysis, while the high cost and mechanical complexity of the commercial instrumentation limit the applications in personalized single-cell analysis. For this issue, we hereby construct an open and low-cost flow cytometer. It is highly compact to integrate the functions of (1) single cell aligning by a lab-made modularized 3D hydrodynamic focusing device, and (2) fluorescence detection of the single cells by a confocal laser-induced fluorescence (LIF) detector. The ceiling cost of the entire hardware for the LIF detection unit and 3D focusing device is $ 3200 and $ 400 respectively. A sheath flow velocity of 150 µL/min produces a focused sample stream of 17.6 µm × 14.6 µm at sample flow of 2 µL/min, based on the LIF response frequency and the laser beam spot diameter. The assay performance of the flow cytometer was evaluated by characterizing fluorescent microparticles and acridine orange (AO) stained HepG2 cells, producing throughputs of 40.5/s and 6.2/s respectively. Favorable assay precision and accuracy were demonstrated by the agreement of frequency histogram with imaging analysis, and good Gaussian-like distributions of fluorescent microparticles and AO-stained HepG2 cells. Practically, the flow cytometer was successfully applied for the evaluation of ROS generation in single HepG2 cells.


Assuntos
Corantes , Hidrodinâmica , Citometria de Fluxo/métodos , Laranja de Acridina , Lasers
4.
Se Pu ; 41(1): 87-93, 2023 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-36633080

RESUMO

Glutathione (GSH) is vital for oxidative stress resistance and heavy metals detoxification. It is significant to develop a sensitive and accurate quantitative GSH approach for the toxicity mechanism for studying heavy metals in cells. A high-sensitive capillary electrophoresis-laser induced fluorescence (CE-LIF) detection approach was proposed in this study to detect GSH content in cells. The approach employed HepG2 cells as an object and 2,3-naphthalenedicarboxaldehyde (NDA) with the active group of aromatic o-dialdehyde as a labeling reagent. The effects of buffer solution types, pH, additives on the GSH reaction rate with NDA, and the sensitivity of NDA-GSH were systematically investigated. The sensitivity of NDA-GSH and the reaction rate of GSH with NDA were compared in tris(hydroxymethyl)aminomethane (Tris) buffer solution at pH 7.4 or 9.2 and borate-Tris buffer solution at pH 9.2. The results revealed that the NDA-GSH sensitivity was the highest and the reaction rate of GSH and NDA was the fastest in borate buffer solution at pH 9.2. The effects of the four additives on the sensitivity of NDA-GSH were further compared. The best additive was revealed to be ß-cyclodextrin (ß-CD). GSH reacted with NDA to reach equilibrium within 5 min under the optimal experimental conditions, and the electrophoretic signal of NDA-GSH could be seen in 3 min. Quantitative analysis of GSH in HepG2 cells was performed using an external standard approach by determining a series of GSH standard solutions. The results revealed that the approach had a good linear relationship with the peak area vs. concentration (0.01-20.00 mmol/L) of GSH. The limit of detection (LOD) and limit of quantification (LOQ) of GSH were determined using signal-to-noise ratios of 3 (S/N=3) and 10 (S/N=10), which were 0.006 µmol/L and 0.020 µmol/L, respectively. The approach's spiked recoveries were 95.7%-112.6%, with relative standard deviations of the approach being 3.8%-5.0% (n=3). This approach offers high sensitivity, good stability, accuracy, and reliability. To study the relationship between the toxicity of arsenic and chromium on HepG2 cells and the content of GSH in HepG2 cells, the effects of arsenic and chromium with different valences on cell viability were analyzed. The results illustrated that the cytotoxicity of potassium dichromate (Cr(Ⅵ)) was the strongest. The variations of GSH content in HepG2 cells stimulated with arsenite (As(Ⅲ)), arsenate (As(Ⅴ)), chromium chloride (Cr(Ⅲ)), and Cr(Ⅵ) were analyzed by the proposed approach and analysis of intracellular GSH imaging. The results revealed that the stimulation group i. e. analyzed doses (low-dose 2 mg/L, high-dose 5 mg/L) of As(Ⅲ), As(Ⅴ), and Cr(Ⅲ) had no obvious effect on GSH content in HepG2 cells compared with the control group, whereas high-dose Cr(Ⅵ) can significantly reduce GSH content in HepG2 cells. Considering the analysis of cytotoxicity of As(Ⅲ), As(Ⅴ), Cr(Ⅲ), and Cr(Ⅵ), it shows that the content of GSH in HepG2 cells is related to cytotoxicity, and the content of GSH will decrease with the increase in cytotoxicity.


Assuntos
Arsênio , Fluorescência , Reprodutibilidade dos Testes , Boratos , Glutationa/análise , Glutationa/química , Cromo , Eletroforese Capilar/métodos , Lasers
5.
Lab Chip ; 22(21): 4238-4245, 2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36194170

RESUMO

In aptamer-based assay schemes, aptamer probes not labeled with biomarkers have to be eliminated before testing, which may lead to a tremendous waste of precious probes. We herein propose a microfluidics system integrating an aptamer concentration gradient generator (Apt-CGG) and a dual single-cell culturing array (D-SCA), termed Mi-Apt-SCA. This facilitates the precise construction of a nanoscale-gradient microenvironment and the high-throughput profiling of single-cell growth/phenotypes in situ with the minimal consumption of Apt-probe. Unlike previous snakelike mixers, the choreographed winding-ravined aptamer dual-spiral micromixer (Apt-WD-mixer) in Apt-CGG could allow thorough blending to generate linear concentration gradients of aptamer (quasi-non-Newtonian fluid) under the action of continuous fluidic wiggles and bidirectional Dean flow. In contrast to other trap-like systems, the mild vortex allows single-cell growth in an ultra-tender fluidic microenvironment using triple-jarless single-cell culture capsules (TriJ-SCCs) in D-SCA (shear stress: 3.43 × 10-5 dynes per cm2). The minimum dosage of aptamer probe required for exploring PDL1 protein expression in two hepatoma cell lines is only one-900th of that required by conventional protocols. In addition, this approach facilitated the profiling of ITF-ß/cisplatin-mediated single-cell/cell-cluster phenotypes.


Assuntos
Aptâmeros de Nucleotídeos , Produtos Biológicos , Neoplasias Hepáticas , Humanos , Aptâmeros de Nucleotídeos/metabolismo , Cisplatino , Microambiente Tumoral
6.
Anal Chim Acta ; 1226: 340268, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36068064

RESUMO

The cellular metabolism of metals is highly critical to elucidate their potential cytotoxicity or cell protection mechanism. In this work, an asymmetric serpentine microfluidic device (ASMD) with high sampling efficiency and excellent focusing performance was developed for single-cell focusing. ASMD coupling with ICP-MS ensures single-cell assay to provide the information for trivalent arsenic (As(III)) uptake by HepG2 cells, which reveals the heterogeneity of cellular arsenic distribution, and elucidates the arsenic elimination behaviors in single HepG2 cells. Further, the metabolism and transformation of As(III) in HepG2 cells was tracked by hyphenating capillary electrophoresis (CE) separation with ICP-MS. The results for single-cell analysis and arsenic elimination kinetics illustrated that the half-life of arsenic elimination is 0.9 ± 0.04 h with the elimination constant of 0.77 ± 0.03, i.e., 77% of accumulated As in HepG2 cells may be eliminated per hour. Moreover, arsenobetaine (AsB) was identified to be the main metabolite and biotransformation species of As in HepG2 cells. ASMD-ICP-MS and CE-ICP-MS are powerful for tracking the fate of metals or metal drugs in single cells to comprehensively understand their metabolic pathway and transformation behaviors.


Assuntos
Arsênio , Arsênio/análise , Arsênio/toxicidade , Eletroforese Capilar/métodos , Células Hep G2 , Humanos , Espectrometria de Massas/métodos , Análise Espectral
7.
Neurosurg Rev ; 45(4): 2709-2715, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35391607

RESUMO

Trigeminal neuralgia (TN) due to vertebrobasilar dolichoectasia (VBD) is a rare disease that can be challenging to treat. The objectives of this study are to investigate the characteristics of patients with TN due to VBD and to analyze the efficacy of microvascular decompression (MVD) by the interposition method for treatment of the condition. From 2010 until 2020, the data of 30 patients with TN due to VBD who were treated with MVD by the interposition method were analyzed retrospectively. The characteristics of the patients were compared with those of patients with non-VBD TN (n = 815). Kaplan-Meier survival analysis was performed to determine pain-free survival. The 30 patients (21 males, 9 females; mean age, 63.03 years) accounted for 3.55% of all patients with TN during the study period. In 30 patients, the offending vessel was the basilar artery (BA) in 1 patient, the vertebral artery (VA) in 6 patients, the VA plus the superior cerebellar artery (SCA) in 6 patients, the VA plus the anterior inferior cerebellar artery (AICA) in 12 patients, and the VA + SCA + AICA in 5 patients. Compared to non-VBD TN patients, those with TN due to VBD were significantly more likely to be male, to have TN of the left side, and to have hypertension (all P < 0.001). Mean age at surgery (P = 0.057) and symptom duration (P = 0.308) were comparable between the two groups. All 30 patients had immediate relief of facial pain after MVD and could stop medication. There were no postoperative complications. Over mean follow-up of 76.67 months, 3 patients had recurrence. The mean duration of pain-free survival was 70.77 months. In conclusions, TN due to VBD appears to be more likely in males, in those with hypertension, and to involve the left side. The interposition method performed by experienced and skilled neurosurgeons is a safe and effective treatment for TN due to VBD. Further studies are needed to analyze the associated long-term results and the pain recurrence rate among this special population.


Assuntos
Hipertensão , Cirurgia de Descompressão Microvascular , Neuralgia do Trigêmeo , Insuficiência Vertebrobasilar , Feminino , Humanos , Hipertensão/complicações , Masculino , Cirurgia de Descompressão Microvascular/métodos , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Neuralgia do Trigêmeo/etiologia , Neuralgia do Trigêmeo/cirurgia , Insuficiência Vertebrobasilar/complicações , Insuficiência Vertebrobasilar/cirurgia
8.
Ann Clin Lab Sci ; 51(6): 844-851, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34921038

RESUMO

OBJECTIVE: The chemokine receptor CX3CR1 and its specific ligand fractalkine (CX3CL1, FKN) has been implicated in modulating inflammatory and fibroproliferative diseases. The current study was performed to investigate the correlation of serum fractalkine levels with disease severity of liver fibrosis/cirrhosis (LC). METHODS: 162 LC patients and 140 healthy controls well enrolled in our study. Serum fractalkine levels were detected using commercial ELISA kit. Liver biopsy specimens were obtained using 16 G disposable needle in LC patients. The Child-Pugh grade was recorded to assess liver function. ROC curve analysis was performed to assess the potential diagnostic power of serum fractalkine with regard to the disease severity of Child-Pugh grade system. Pathological assessment of cirrhotic severity was performed by Laennec staging system. The L3 skeletal muscle index (L3SMI) was applicated to assess the nutrition status. RESULTS: Serum fractalkine levels were significantly higher in LC patients compared with healthy controls. The case group included 50 Child-Pugh A patients, 59 Child-Pugh B patients, and 53 Child-Pugh C patients. Cirrhosis patients with Child-Pugh C had drastically higher serum fractalkine levels compared with those with Child-Pugh B and A. Child-Pugh B patients showed significantly higher serum PACAP concentrations compared with those with Child-Pugh A. ROC curve analysis demonstrated that serum fractalkine may act as a potential indicator for disease progression of LC determined by Child-Pugh classification. Besides, serum fractalkine levels were positively related to ALT and AST concentrations and negatively related to L3SMI. CONCLUSION: Serum fractalkine levels were positively associated with disease severity of LC.


Assuntos
Quimiocina CX3CL1/metabolismo , Inflamação , Cirrose Hepática , Fígado , Quimiocina CX3CL1/sangue , Correlação de Dados , Progressão da Doença , Feminino , Humanos , Inflamação/sangue , Inflamação/metabolismo , Ligantes , Fígado/diagnóstico por imagem , Fígado/patologia , Cirrose Hepática/sangue , Cirrose Hepática/diagnóstico , Cirrose Hepática/etiologia , Cirrose Hepática/imunologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Receptores de Quimiocinas , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X
9.
ACS Appl Mater Interfaces ; 13(36): 43668-43675, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34473482

RESUMO

The efficient recognition of circulating tumor cells (CTCs) with an aptamer probe confers numerous benefits; however, the stability and binding affinity of aptamers are significantly hampered in real biological sample matrices. Inspired by the efficient preying mechanism by multiplex tubing feet and endoskeletons of sea urchins, we engineered a superefficient biomimetic single-CTC recognition platform by conjugating dual-multivalent-aptamers (DMAs) Sgc8 and SYL3C onto AuNPs to form a sea urchin-like nanoprobe (sea urchin-DMA-AuNPs). Aptamers Sgc8 and SYL3C selectively bind with the biomarker proteins PTK7 and EpCAM expressed on the surface of CTCs. CTCs were captured with 100% efficiency, followed by sorting on a specially designed multifunctional microfluidic configuration, integrating a single-CTC separation unit and a hydrodynamic filtrating purification unit. After sorting, background-free analysis of biomarker proteins in single CTCs was undertaken with inductively coupled plasma mass spectrometry by measuring the amount of 197Au isotope in sea urchin-DMA-AuNPs. With respect to a single-aptamer nanoprobe/-interface, the dual-aptamer nanoprobe improves the binding efficiency by more than 200% (Kd < 0.35 nM). The microchip facilitates the recognition of single CTCs with a sorting separation rate of 93.6% at a flow rate of 60 µL min-1, and it exhibits 73.8 ± 5.0% measurement efficiency for single CTCs. The present strategy ensures the manipulation and detection of a single CTC in 100 µL of whole blood within 1 h.


Assuntos
Aptâmeros de Nucleotídeos/química , Separação Celular/métodos , Ácidos Nucleicos Imobilizados/química , Dispositivos Lab-On-A-Chip , Nanopartículas Metálicas/química , Células Neoplásicas Circulantes/química , Materiais Biomiméticos/química , Moléculas de Adesão Celular/química , Linhagem Celular Tumoral , Molécula de Adesão da Célula Epitelial/química , Ouro/química , Humanos , Espectrometria de Massas , Técnicas Analíticas Microfluídicas/métodos , Receptores Proteína Tirosina Quinases/química
10.
Balkan Med J ; 38(4): 229-238, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34274912

RESUMO

BACKGROUND: Circular RNAs (CircRNAs) have been recently implicated in the progression of pancreatic cancer (PC). AIMS: To investigate the involvement of CircCCT3 in PC and studying its interactions and functioning during the progression of PC in vitro and in vivo, using methods of molecular biology and bioinformatics. STUDY DESIGN: Experimental study. METHODS: The expressions of CircCCT3 and miR-613 in pancreatic carcinoma tissues and cell lines were evaluated by quantitative real-time polymerase chain reaction (PCR). The relationship between clinical pathologic features as well as the survival rate and CircCCT3 expression was analyzed with chi-square test and the Kaplan-Meier method. CCK-8, wound healing, transwell assays, and the fluorescein isothiocyanate- AnnexinV/propidium iodide (FITC-AnnexinV/PI) assay were used to assess cell proliferation, migration, invasion, and apoptosis after CircCCT3 overexpression or downregulation. The Dual- Luciferase reporter assay, RNA immunoprecipitation (RIP), RNA pull-down and fluorescence in situ hybridization (FISH) assays were performed to validate the potential interaction of CircCCT3, miR-613, and vascular endothelial growth factor (VEGFA). The nude mouse xenograft tumor assay was used to detect CircCCT3 effects on pancreatic tumorigenesis in vivo. Western blotting analysis was performed to examine the VEGFA and the vascular endothelial growth factor receptor 2 (VEGFR2) protein expressions following. RESULTS: CircCCT3 expression was significantly increased in PC tissues (3.41 ± 0.57 vs. 1.00 ± 0.10, P < .01) and cell lines (Patu8988 2.57 ± 0.20; SW1990 2.88 ± 0.10; BxPC-3 2.45 ± 0.20; Panc02 2.99 ± 0.10 vs. H6c7 1.00 ± 0.10; all P < .001). CircCCT3 expression was negatively correlated with miR-613 expression. PC patients with high CircCCT3 expression exhibited significantly poorer overall survival rate than those patients with low CircCCT3 expression (P = .013). Moreover, it was found that CircCCT3 promoted cell proliferation, migration, and invasion, and inhibited cell apoptosis in PC cells. The CircCCT3 acted as a sponge for the miR-613 to facilitate VEGFA and VEGFR2 expression. si-CirCCT3 also inhibited tumor growth of PC in nude mice. si-CircCCT3 reduced VEGFA and VEGFR2 expression, whereas overexpression of CircCCT3 increased VEGFA and VEGFR2 expression. CONCLUSION: Increased CircCCT3 suggests a poor prognosis for PC patients and promotes the migration and invasion through targeting VEGFA/VEGFR2 signaling. CircCCT3 may serve as a potential and promising therapeutic target for PC treatment.


Assuntos
MicroRNAs/antagonistas & inibidores , RNA Circular/farmacologia , Transdução de Sinais/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/efeitos dos fármacos , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/efeitos dos fármacos , Biomarcadores Tumorais/análise , Linhagem Celular , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos
11.
Anal Chem ; 93(23): 8203-8209, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34077198

RESUMO

A two-dimensional cytometry platform (CytoLM) with high sensitivity and high temporal resolution is developed for single-particle and single-cell sampling and analysis. First, a Dean flow-assisted vortex capillary cell sampling (VCCS) unit confines the sample stream in curved flow and drives to focus and align the particles or cells in a small probe volume. By coupling VCCS to a laser-induced fluorescence (LIF) detector with data acquisition and processing capability, a high-throughput single-particle/cell analysis system (VCCS-LIF) was established. The particle analysis throughput of 119.42/s and a detection recovery of 78.20 ± 1.75% were achieved at a density of 9.16 × 104/mL for fluorescent particles, and the cell analysis throughput is 48.20/s at a density of 1.5 × 105/mL. Second, the CytoLM platform is constructed by hyphenating VCCS-LIF with inductively coupled plasma mass spectrometry (ICP-MS). In the analysis of HepG2 cells by Ag+ incubation and AO staining, 10,760 fluorescence bursts and 3068 MS events were observed in 240 s. Invalid signals due to undispersed cells were controlled at 3.80% for LIF and 1.01% for MS, with a proportion of effective signal of >96.20%. After peak identification and integral processing of the original data, the statistical results including peak area, height, width, and spacing are obtained concurrently and the information on concentration and elemental quantification of single cells is evaluated. CytoLM facilitates high-throughput, multi-dimensional, and multi-parameter characterization of particles and cells, and it may provide vast potential in life science analysis.


Assuntos
Imagem Individual de Molécula , Análise de Célula Única , Lasers , Espectrometria de Massas , Análise Espectral
12.
Anal Chim Acta ; 1166: 338540, 2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34023001

RESUMO

The study of silver species and their distribution/transformation in cell interior is of high significance for the elucidation of toxicology of silver nanoparticles (AgNPs). The intracellular speciation of dissolved Ag(I) and AgNPs was reported. The analytical platform integrated capillary electrophoresis (CE) to inductively coupled plasma-mass spectrometry (ICP-MS) incorporating a high efficiency interface and a high performance spiral flow spray chamber (SFSC). The interface and the SFSC provide a favorable detection limit of 87 ng L-1 for the dissolved Ag(I). Total silver content was quantified by ICP-MS subject to digestion of the cell lysate, and quantification of AgNPs was carried out by subtraction. The speciation of dissolved Ag(I) and AgNPs in culture medium and HepG2 cells was performed, with RSDs of <3% for relative peak area and <2% for migration time, as well as spiking recoveries of 93.8%-94.3% in opti-MEM and 92.7%-106.6% in cell lysate. The present study indicated higher solubility of AgNPs in the cell interior with respect to that in the culture medium, due to oxidative stress or acidic microenvironment in the cancer cells.


Assuntos
Nanopartículas Metálicas , Prata , Eletroforese Capilar , Espectrometria de Massas , Análise Espectral
14.
Talanta ; 218: 121065, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32797863

RESUMO

It is of significance to elucidate or understand the intracellular transformation & migration behaviors of heavy metals in specific cells. Herein, we report the fast and efficient separation of cadmium-metallothioneins (Cd-MTs) and Cd2+in cell lysate by a short column capillary electrophoresis (SC-CE), followed by coupling with inductively coupled plasma mass spectrometry (ICP-MS) to facilitate the speciation of intracellular cadmium species. The incorporation of sodium dodecyl sulfate (SDS) in running buffer significantly reduces the peak width of Cd2+from 170 s to 26 s in the electrophoretogram, causing a 5.3-fold improvement on the sensitivity. Linear ranges of 0.5-50 mg L-1,0.056-5.6 mg L-1 and 0.1-10 mg L-1 are achieved for MTs, Cd-MTs (Cd) and Cd2+, respectively, along with detection limits of 0.013 mg L-1 for Cd-MTs (Cd) and 0.020 mg L-1 for Cd2+. The transformation of cadmium in HepG2 and MCF-7 cells is evaluated after their incubation with Cd2+ reinforced culture medium. Intracellular free Cd2+ cation and Cd-MTs are identified, along with Cd2+ transformation to Cd-glutathione (GSH) adduct/complex, as further demonstrated by ESI-MS.


Assuntos
Cádmio , Eletroforese Capilar , Cádmio/toxicidade , Glutationa , Humanos , Células MCF-7 , Espectrometria de Massas
15.
World Neurosurg ; 141: e508-e513, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32492542

RESUMO

OBJECTIVE: Secondary trigeminal neuralgia (TN) caused by cerebellopontine angle (CPA) tumors are rare, although TN may be a primary manifestation in the neurosurgery department. In this study, we aimed to retrospectively assess patients with CPA tumor-induced TN from a single center. METHODS: Of 819 consecutive patients with TN treated at our center between 2007 and 2017, 36 with CPA tumor-induced TN were enrolled, and their medical and surgical records were analyzed. RESULTS: The 36 patients accounted for 4.4% of all patients with TN. A comparison of patients with classic and tumor-induced TN indicated significant intergroup differences in the mean age at surgery (58.94 vs. 49.33 years, P = 0.000), the mean age at onset of TN (52.01 vs. 38.04 years), and affected side (298/485 vs. 22/14 in left/right, P = 0.006); no such difference was noted in the sex ratio (0.598 vs. 0.385, P = 0.214). The rates of excellent, good, and fair clinical outcomes were 80.56%, 13.89%, and 2.78%, respectively. The offending vessels found during surgery included the superior and anterior inferior cerebellar arteries in 3 and 4 cases, respectively. Postoperative complications included aseptic meningitis (1 case), facial numbness (2 cases), hearing disturbance (3 cases), facial palsy (4 cases), hemorrhage (1 case), and diplopia (2 cases). CONCLUSIONS: Secondary TN caused by CPA tumors is not as frequent as classic TN. Compared with classic TN, tumor-induced TN is characterized by symptom onset and surgery at a younger age. Direct compression rather than chemical irritation is the cause of secondary TN.


Assuntos
Neuroma Acústico/complicações , Neuroma Acústico/cirurgia , Neuralgia do Trigêmeo/etiologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos/métodos , Estudos Retrospectivos , Resultado do Tratamento
16.
Anal Chem ; 92(9): 6604-6612, 2020 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-32233376

RESUMO

Single-cell analysis facilitates perception into the most essential processes in life's mysteries. While it is highly challenging to quantify them at the single-cell level, where precise single-cell sampling is the prerequisite. Herein, a real-time single-cell quantitative platform was established for high-throughput droplet-free single-cell sampling into time-resolved (TRA) ICP-MS and real-time quantification of intracellular target elements. The concentrated cells (2 × 106 cells mL-1) were spontaneously and orderly aligned in a spiral microchannel with 104 periodic dimensional confined micropillars. The quantification is conducted simultaneously by internal standard inducing from another branch channel in the chip. The flow-rate-independent feature of single-cell focusing into an aligned stream within a wide range of fluidic velocities (100-800 µL min-1) facilitates high-throughput, oil-free, single-cell introduction into TRA-ICP-MS. The system was used for real-time exploration of intracellular antagonism of Cu2+ against Cd2+. an obvious antagonistic effect was observed for the MCF-7 cell by culturing for 3, 6, 9, and 12 h with 100 µg L-1 Cd2+ and 100 µg L-1 Cu2+, and a rivalry rate of 12.8% was achieved at 12 h. At identical experimental conditions, however, limited antagonistic effect was encountered for a bEnd3 cell within the same incubation time period, with a rivalry rate of 4.81%. On the contrary, an antagonistic effect was not observed for the HepG2 cell by culturing for 6 h, while an obvious antagonistic effect was found by further culturing to 12 h, with a rivalry rate of 10.43%. For all three cell lines, significant heterogeneity was observed among individual cells.


Assuntos
Ensaios de Triagem em Larga Escala , Análise de Célula Única , Cádmio/química , Cobre/química , Humanos , Espectrometria de Massas , Tamanho da Partícula , Propriedades de Superfície , Fatores de Tempo , Células Tumorais Cultivadas
17.
World Neurosurg ; 129: e650-e656, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31158546

RESUMO

BACKGROUND: Hyperactive dysfunction syndrome (HDS) of the cranial nerves, such as trigeminal neuralgia (TN), hemifacial spasm (HFS), and glossopharyngeal neuralgia (GPN), is commonly managed by microsurgical treatment. However, certain patients may present a combination of these syndromes in the neurosurgery department. Here, we aimed to retrospectively assess patients with combined HDS from a single center. METHOD: Of 1275 consecutive patients with HDS treated at our center between 2007 and 2017, 37 patients with combined HDS were enrolled, and their medical and surgical records were analyzed. RESULTS: The patients with combined HDS, accounting for 2.9% of all patients with HDS, included 22 patients with bilateral TN, 5 patients with TN-HFS, 8 patients with TN-GPN, and 2 patients with GPN-HFS. A comparison of patients with single and combined HDS indicated a significant difference in the mean age at initial diagnosis (63.57 vs. 56.18 years, P = 0.000) but no such difference in the sex ratio (0.54 vs. 0.59, P = 0.865) or incidence of hypertension (32.43% vs. 24.56%, P = 0.274). In total, 32 microvascular decompression (MVD) procedures were performed in the 27 patients with combined HDS, and repeated MVD was required in 5 patients with bilateral TN. Of the 27 patients who underwent MVD, 25 (92.6%) experienced clinical cure or obvious alleviation. CONCLUSIONS: Combined HDS involves a group of functional disturbance disorders affecting specific cranial nerves, and it may include TN, HFS, and GPN. In addition to gender and incidence of hypertension, age appeared to be a vital indicator for the development of combined HDS, although this finding was inconsistent in previous studies. MVD appears to be a safe and effective treatment for combined HDS, with a high rate of long-term success.


Assuntos
Doenças dos Nervos Cranianos/cirurgia , Nervos Cranianos/cirurgia , Cirurgia de Descompressão Microvascular/métodos , Procedimentos Neurocirúrgicos/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
18.
Mol Divers ; 22(4): 893-906, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29934672

RESUMO

Chalcones containing tertiary amine side-chains have potent activity as acetylcholinesterase (AChE) inhibitors. However, the effects of the location of the tertiary amine groups as well as of other groups on AChE and butyrylcholinesterase (BChE) activity have not been reported. Here, we report the synthesis and testing of 36 new coumarin-chalcone hybrids (5d-7j, 9d-11f, 12k-13m) against AChE and BChE. The nature and position of the chalcone substituents had major effects on inhibitory activity as well as selectivity for AChE over BChE. Compounds with para-substituted chalcone fragments in which the substituents were choline-like had potent activity against AChE and poor activity against BChE, while ortho-substituted analogs exhibited an opposite effect. Replacement of the terminal amine groups by amide, alkyl or alkenyl groups abrogated activity. Compound 5e showed potent inhibitory activity [Formula: see text]) and good selectivity for AChE over BChE (ratio 27.4), and a kinetic study showed that 5e exhibited mixed-type inhibition against AChE. Computational docking results indicate that 5e binds to Trp 279, Tyr334 and Trp 84 in AChE, but only to Trp 82 in BChE. Overall, the results show that coumarin-chalcone hybrids with choline-like side-chains have promising activity and selectivity against AChE and be promising therapeutic leads for Alzheimer's disease.


Assuntos
Acetilcolinesterase/química , Butirilcolinesterase/química , Chalconas/química , Inibidores da Colinesterase/química , Cumarínicos/química , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade
19.
Nat Prod Res ; 32(6): 743-747, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28617100

RESUMO

Naringin, as a component universal existing in the peel of some fruits or medicinal plants, was usually selected as the material to synthesise bioactive derivates since it was easy to gain with low cost. In present investigation, eight new acacetin-7-O-methyl ether Mannich base derivatives (1-8) were synthesised from naringin. The bioactivity evaluation revealed that most of them exhibited moderate or potent acetylcholinesterase (AChE) inhibitory activity. Among them, compound 7 (IC50 for AChE = 0.82 ± 0.08 µmol•L-1, IC50 for BuChE = 46.30 ± 3.26 µmol•L-1) showed a potent activity and high selectivity compared with the positive control Rivastigmine (IC50 for AChE = 10.54 ± 0.86 µmol•L-1, IC50 for BuChE = 0.26 ± 0.08 µmol•L-1). The kinetic study suggested that compound 7 bind to AChE with mix-type inhibitory profile. Molecular docking study revealed that compound 7 could combine both catalytic active site (CAS) and peripheral active site (PAS) of AChE with four points (Trp84, Trp279, Tyr70 and Phe330), while it could bind with BuChE via only His 20.


Assuntos
Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Flavanonas/química , Acetilcolinesterase/metabolismo , Animais , Butirilcolinesterase/metabolismo , Domínio Catalítico , Técnicas de Química Sintética , Inibidores da Colinesterase/síntese química , Avaliação Pré-Clínica de Medicamentos/métodos , Flavonas/química , Concentração Inibidora 50 , Cinética , Bases de Mannich , Éteres Metílicos/química , Simulação de Acoplamento Molecular , Ratos
20.
Chin Med J (Engl) ; 126(12): 2354-60, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23786953

RESUMO

BACKGROUND: A recent study demonstrated that the inflammatory response accompanying necrotic brain injury played an important role in stroke. Thus, inhibition of this response may help to stop the expansion of infarcts. It has been also shown that the spleen, a major peripheral immune organ, plays a role in stroke-induced immune responses. This study aimed to establish rat models of middle cerebral artery occlusion (MCAO) and to investigate the effect of splenectomy and possible mechanisms in that rat models. METHODS: Infarct size in a stroke model was measured with the Nissl body staining method, numbers of inflammatory cells in ischemic regions were detected by immunofluorescence staining, and inflammatory factors were assayed by enzyme-linked immunosorbent assay and real-time polymerase chain reaction (PCR) in brain homogenates and sera. The significance of differences was determined by one-way analysis of variance (ANOVA) followed by the least significant difference post hoc test. RESULTS: Infarct size in the brain of rats that underwent splenectomies 2 weeks before permanent MCAO ((34.93 ± 3.23)%) was over 50% smaller than that of rats subjected to the stroke surgery alone ((74.33 ± 2.36)%, P < 0.001; (77.30 ± 2.62)%, P < 0.001). Lower numbers of T cells, neutrophils, and macrophages in brain tissue and lower levels of pro-inflammatory cytokines, such as interleukin (IL)-1ß and tumor necrosis factor (TNF)-α, were observed in rats that underwent splenectomies, compared with the two other groups, but splenectomized rats showed higher levels of the anti-inflammatory factor IL-10 in the brain. CONCLUSION: The mechanism(s) by which splenectomy protects brain from damage induced by stroke may correlate with the decreased numbers of inflammatory cells and changes in inflammatory cytokines.


Assuntos
Infarto Cerebral/prevenção & controle , Inflamação/prevenção & controle , Esplenectomia , Acidente Vascular Cerebral/complicações , Animais , Citocinas/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Linfócitos T/imunologia
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