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1.
Anal Chem ; 2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38330440

RESUMEN

Labile toxic pollutants detection remains a challenge due to the problem that a single method is prone to producing false-negative/-positive signals. The construction of a multisignal sensing platform with the advantages of different strategies is an effective way to solve this problem. Herein, a novel resonant light scattering (RLS), fluorescent and rapid visual multisignals sensing strategy for p-aminophenol (p-AP) detection was designed based on the adsorption and oxidation effects of defective amino-functionalized Ag-based nano metal-organic frameworks (NH2-Ag-nMOFs). In this reaction process, NH2-Ag-nMOFs with incomplete coordination oxidize H2O2 to produce singlet oxygen (1O2) which rapidly oxidizes p-AP, leading to the reduction of Ag+ to Ag0, thereby disrupting the structure of NH2-Ag-nMOFs and resulting in fluorescence quenching of NH2-Ag-nMOFs. Synchronously, owing to Ag0 aggregation and p-AP oxidation, the color of the system changed from colorless to purplish-red and pale brown within 20 s. The assay has realized the rapid naked-eye detection of 5 µM p-AP rapidly. Additionally, thanks to the intermolecular hydrogen bonding, NH2-Ag-nMOFs-p-AP aggregates formed, which enhanced the RLS signal. With the RLS signal, the designed multisignals sensing platform can analyze p-AP at a concentration as low as 11 nM and yield a wider dynamic response range than any single signal strategy reported before, which can quickly meet the measurement requirement of different actual samples. Overall, the proposed strategy without assembling various signal indicators presented an accurate, rapid, cost-effective, and sensitive multisignals sensing platform for p-AP analysis and has great prospects in labile toxic pollutants monitoring.

2.
Food Chem ; 443: 138557, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38280363

RESUMEN

CRISPR (clustered regularly interspaced short palindromic repeats) and CRISPR-associated protein (Cas) have gained extensive applications in bioassays. However, CRISPR-based detection platforms are often hampered by limited analytical sensitivity, while nucleic acid-based amplification strategies are usually indispensable for additional signal enhancement with potential risks of amplification leakages. To address these challenges, an amplification-free CRISPR-based bioassay of aflatoxin B1 (AFB1) was proposed by applying single nanoparticle counting. Single-particle mode inductively coupled plasma mass spectrometry (Sp-ICPMS) has been regarded as a sensitive tool for nanoparticle counting since one nanoparticle can generate considerable signals above backgrounds. With AFB1, activator strands were introduced to initiate the trans-cleavage of CRISPR/Cas12a for cutting the nanoparticles-tagged-magnetic beads, which were transduced to nanoparticle count signals after separation. Finally, a pico-mole level limit-of-detections (LODs) with moderate selectivity was achieved. Certified reference materials (CRMs) analysis and recovery tests were conducted with promising results. To our best knowledge, this is the first report of the single particle counting-based CRISPR/Cas12a biosensing study.


Asunto(s)
Técnicas Biosensibles , Nanopartículas , Aflatoxina B1 , Sistemas CRISPR-Cas , Bioensayo , Certificación
3.
J Hepatocell Carcinoma ; 10: 369-382, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36915393

RESUMEN

Background: FAT atypical cadherin 1 (FAT1) acts as a tumor suppressor or oncogene, which regulates cell adherence, proliferation, motility, and actin kinetics. FAT1 gene expression is closely related to hepatocarcinogenesis; however, the function and mechanism of FAT1 in hepatocellular carcinoma (HCC) remain unclear. Methods: Here, we screened for the FAT1, which is intimately linked to the development and progression of HCC, both in circulating tumor cells (CTCs) and tumor tissues using next generation sequencing (NGS). Immunohistochemical staining was performed to detect FAT1 protein expression. To determine the impact of FAT1 on epithelial-mesenchymal transition (EMT), migration and invasion of HCC, an in vitro transwell assay and Western blot were performed. Moreover, Gene Set Enrichment Analysis was carried out to discover the underlying mechanism. Finally, animal experiments were conducted to confirm the effects of FAT1 on HCC metastasis and tumorigenicity. Results: Our results showed that FAT1 expression was decreased in HCC tissues, while in vitro and in vivo, the FAT1 knockdown facilitated invasion, cell motility, colony formation, and proliferation. FAT1 knockdown also resulted in decreased expression of E-cadherin and markedly elevated expression of N-cadherin, vimentin, and snail. We also confirmed our hypothesis from the analysis of group differences in the CTC phenotype and lung metastasis in nude mice. Conclusion: Our findings illustrated that FAT1 played a negative regulatory role in the HCC EMT and metastasis, providing further evidence for the role played by FAT1 in the formation and progression of HCC.

4.
Hepatol Commun ; 7(1): e0006, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36633475

RESUMEN

BACKGROUND: Exosomal proteins from cancer cells are becoming new biomarkers for cancer monitoring and efficacy evaluation. However, their biological function and molecular mechanism underlying tumor metastasis are largely unknown. METHODS: Bioinformatic methods such as bulk gene expression analysis, single-cell RNA sequencing data analysis, and gene set enrichment analysis were employed to identify metastasis-associated proteins. The in vitro and in vivo experiments were used to investigate the function of RAB13 in HCC metastasis. RESULTS: We identified RAB13 as one of the critical regulators of metastasis in HCC-derived exosomes for the first time. In vitro, the invasiveness of HCC cell lines could be attenuated by RAB13 silence. In vivo, tumor size and proportion of high-grade lung metastatic nodule could be reduced in the mice with orthotopic transplantation of tumors and intravenously injected with exosomes derived from MHCC97H cell with RAB13 silence (si-RAB13-Exo), as compared with those without RAB13 silence (si-NC-Exo). Moreover, in si-RAB13-Exo group, circulating tumor cell counts were decreased at the third, fourth, and fifth weeks after orthotopic transplantation of tumors, and MMP2 (matrix metalloproteinase 2)/TIMP2 (tissue inhibitor of metalloproteinases 2) ratio was also significantly decreased. In addition, RAB13 expression was also associated with VEGF levels, microvessel density, and tube formation of vascular endothelial cells by both in vitro and in vivo models, indicating that RAB13 was associated with angiogenesis in HCC. CONCLUSIONS: We have demonstrated exosomal RAB13 as a potential regulator of metastasis for HCC by in silico, in vitro, and in vivo methods, which greatly improve our understanding of the functional impact of exosomal proteins on HCC metastasis.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animales , Ratones , Carcinoma Hepatocelular/patología , Células Endoteliales/metabolismo , Neoplasias Hepáticas/patología , Metaloproteinasa 2 de la Matriz , Proteómica , Factor A de Crecimiento Endotelial Vascular/metabolismo
5.
J Nanobiotechnology ; 21(1): 25, 2023 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-36681851

RESUMEN

BACKGROUND: Hematogenous metastasis is essential for the progression of advanced hepatocellular carcinoma (HCC) and can occur even after patients receive multidisciplinary therapies, including immunotherapy and hepatectomy; circulating tumor cells (CTCs) are one of the dominant components of the metastatic cascade. However, the CTC capture efficiency for HCC is low due to the low sensitivity of the detection method. In this study, epithelial cell adhesion molecule (EpCAM)/vimentin/Glypican-3 (GPC3) antibody-modified lipid magnetic spheres (LMS) were used to capture tumor cells with epithelial phenotype, mesenchymal phenotype and GPC3 phenotype, respectively, in order to capture more CTCs with a more comprehensive phenotype for monitoring tumor metastasis. RESULTS: The novel CTC detection system of Ep-LMS/Vi-LMS/GPC3-LMS was characterized by low toxicity, strong specificity (96.94%), high sensitivity (98.12%) and high capture efficiency (98.64%) in vitro. A sudden increase in CTC counts accompanied by the occurrence of lung metastasis was found in vivo, which was further validated by a clinical study. During follow-up, the rapid increase in CTCs predicted tumor progression in HCC patients. Additionally, genetic testing results showed common genetic alterations in primary tumors, CTCs and metastatic tissues. The proportion of patients predicted to benefit from immunotherapy with the CTC detection method was higher than that for the tissue detection method (76.47% vs. 41.18%, P = 0.037), guiding the application of clinical individualized therapy. CONCLUSIONS: The Ep-LMS/Vi-LMS/GPC3-LMS sequential CTC capture system is convenient and feasible for the clinical prediction of HCC progression. CTCs captured by this system could be used as a suitable alternative to HCC tissue detection in guiding immunotherapy, supporting the clinical application of CTC liquid biopsy.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Células Neoplásicas Circulantes , Humanos , Carcinoma Hepatocelular/patología , Células Neoplásicas Circulantes/patología , Neoplasias Hepáticas/patología , Molécula de Adhesión Celular Epitelial/metabolismo , Hepatectomía , Biomarcadores de Tumor/metabolismo , Glipicanos
6.
bioRxiv ; 2023 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-38168270

RESUMEN

The mammalian brain is composed of diverse neuron types that play different functional roles. Recent single-cell RNA sequencing approaches have led to a whole brain taxonomy of transcriptomically-defined cell types, yet cell type definitions that include multiple cellular properties can offer additional insights into a neuron's role in brain circuits. While the Patch-seq method can investigate how transcriptomic properties relate to the local morphological and electrophysiological properties of cell types, linking transcriptomic identities to long-range projections is a major unresolved challenge. To address this, we collected coordinated Patch-seq and whole brain morphology data sets of excitatory neurons in mouse visual cortex. From the Patch-seq data, we defined 16 integrated morpho-electric-transcriptomic (MET)-types; in parallel, we reconstructed the complete morphologies of 300 neurons. We unified the two data sets with a multi-step classifier, to integrate cell type assignments and interrogate cross-modality relationships. We find that transcriptomic variations within and across MET-types correspond with morphological and electrophysiological phenotypes. In addition, this variation, along with the anatomical location of the cell, can be used to predict the projection targets of individual neurons. We also shed new light on infragranular cell types and circuits, including cell-type-specific, interhemispheric projections. With this approach, we establish a comprehensive, integrated taxonomy of excitatory neuron types in mouse visual cortex and create a system for integrated, high-dimensional cell type classification that can be extended to the whole brain and potentially across species.

7.
Anal Chem ; 94(49): 17248-17254, 2022 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-36448711

RESUMEN

The occurrence of cancers is often accompanied by the abnormal expression of several sorts of biomarkers (e.g., nucleic acids and proteins). The multiplex assessment of them would substantially aid in the early detection and precise diagnosis, which is often hampered by their different detection schemes, different reaction matrix and reagents, and spectral overlapping. Herein, we propose a simple and sensitive mass spectrometric method for the multiplex detection of nucleic acid and protein, in which liver cancer-related biomarkers miRNA 223 and alpha-fetoprotein (AFP) were selected as model analytes. The self-amplification effect of metal atom-based nanoparticle probes can provide high sensitivity in complex serum samples without any additional amplification procedure. The detection limits for the simultaneous detection of miRNA 223 and AFP were 103 (2.1 pM) and 219 amol (0.15 ng/mL), respectively, with high specificity and selectivity. The proposed method is potentially useful for the rapid screening of cancers.


Asunto(s)
Técnicas Biosensibles , Neoplasias Hepáticas , Nanopartículas del Metal , MicroARNs , Humanos , MicroARNs/análisis , Neoplasias Hepáticas/diagnóstico , Biomarcadores de Tumor , Espectrometría de Masas , Nanopartículas del Metal/química , Límite de Detección , Técnicas Biosensibles/métodos
8.
Anal Chem ; 94(44): 15433-15439, 2022 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-36282892

RESUMEN

Liquid biopsy has become a sought-after technique for disease diagnosis because it provides real-time, dynamic, and comprehensive information that can alleviate the dilemmas faced by tissue biopsy. Multiplexed microRNAs (miRNAs) have been demonstrated to be promising biomarkers in liquid biopsy but fall short in providing simple and sensitive analytical methods. In this work, we established a novel nanoparticle counting strategy to accomplish simultaneous analysis of three breast cancer-associated miRNAs for breast cancer diagnosis. The frequency of nanoparticles not involved in the formation of sandwich structures was detected by single-particle inductively coupled plasma mass spectrometry (SP-ICPMS) to quantify the targets. The detection limits for miR-21, miR-155, and miR-16 were 49, 51, and 55 amol, respectively. The strategy was applied to clinical samples and successfully achieved the diagnosis between normal individuals and breast cancer patients. The area under the curve (AUC) for the combination of the relative expression of miR-21 and miR-155 was 0.818. The above results indicate that this strategy has potential and holds great promise for playing an essential role in cancer diagnosis.


Asunto(s)
Neoplasias de la Mama , MicroARNs , Nanopartículas , Humanos , Femenino , MicroARNs/análisis , Neoplasias de la Mama/patología , Biopsia Líquida , Biomarcadores/análisis , Biomarcadores de Tumor/análisis
9.
Anal Chem ; 94(37): 12899-12906, 2022 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-36069220

RESUMEN

Precision medicine demands the best application of multiple unambiguous biomarkers to bring uniform decisions in disease prognosis. The remarkable development of heterogeneous immunoassay greatly promotes precision medicine when combined with the biomarker combination strategy. Nevertheless, the cumbersome washing steps in heterogeneous immunoassay have inevitably compromised the accuracy because of the sample losses and nature change of the matrix, challenging the further exploration of a more facile and lower limit-of-detection analysis. The new methodologies with high throughputs and specificity are never out of date to provide simultaneous evaluations and uniform decisions on multiple analytes through a simple process. Herein, we propose a new wash-free immunoassay, named differential assay, for multiplexed biomarker monitoring. The method is based on counting the number difference of unbound nanoparticle tags before and after immunoreactions from a solid support (i.e., magnetic microsphere) by single-particle inductively coupled plasma mass spectrometry (sp-ICP-MS), discarding the tedious washing steps. We primarily explore the proof-of-concept proposal within two types (sandwich and competitive assay), demonstrating the good feasibility for further facile clinical practice. To provide efficient multiplexed evaluations, we synthesized PtNPs with four diameters and screened the most suitable size for efficient differential immunoassay. The wash-free strategy was successfully utilized in simultaneous serological biomarker (CA724, CA199, and CEA) evaluation, with results in good accordance with those measured by the clinical routine method. Potentially, the proposed differential bioassay can be regarded as a more facile and valuable tool in malignancy prognosis and cancer recurrence monitoring.


Asunto(s)
Nanopartículas , Neoplasias Gástricas , Biomarcadores de Tumor , Humanos , Inmunoensayo/métodos , Magnetismo , Neoplasias Gástricas/diagnóstico
10.
Front Oncol ; 12: 878923, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35707353

RESUMEN

Background: Hepatocellular carcinoma (HCC) is a leading cause of cancer-related mortality worldwide, but effective early detection and prognostication methods are lacking. Methods: The Cox regression model was built to stratify the HCC patients. The single-cell RNA sequencing data analysis and gene set enrichment analysis were employed to investigate the biological function of identified markers. PLCB1 gain- or loss-of-function experiments were performed, and obtained HCC samples were analyzed using quantitative real-time PCR and immunohistochemistry assay to validate the biological function of identified markers. Results: In this study, we developed a model using optimized markers for HCC recurrence prediction. Specifically, we screened out 8 genes through a series of data analyses, and built a multivariable Cox model based on their expression. The risk stratifications using the Eight-Gene Cox (EGC) model were closely associated with the recurrence-free survivals (RFS) in both training and three validation cohorts. We further demonstrated that this risk stratification could serve as an independent predictor in predicting HCC recurrence, and that the EGC model could outperform other models. Moreover, we also investigated the cell-type-specific expression patterns of the eight recurrence-related genes in tumor microenvironment using single-cell RNA sequencing data, and interpreted their functional roles from correlation and gene set enrichment analyses, in vitro and in vivo experiments. Particularly, PLCB1 and SLC22A7 were predominantly expressed in malignant cells, and they were predicted to promote angiogenesis and to help maintain normal metabolism in liver, respectively. In contrast, both FASLG and IL2RB were specifically expressed in T cells, and were highly correlated with T cell marker genes, suggesting that these two genes might assist in maintaining normal function of T cell-mediated immune response in tumor tissues. Conclusion: In conclusion, the EGC model and eight identified marker genes could not only facilitate the accurate prediction of HCC recurrence, but also improve our understanding of the mechanisms behind HCC recurrence.

11.
Chem Sci ; 13(21): 6270-6275, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35733887

RESUMEN

Explicit interpretation of heterogeneity between prostate-specific antigen (PSA) subtypes is essential for prostate cancer differentiation during different disease courses, whereas a universal protocol with uniform criteria is still lacking across the globe. In this work, a standard-free single magnetic bead (SMB) nanoplatform utilizing metal nanoparticles with optimal diameters was proposed for prostate disease differentiation in a 134-donor model. The inaccuracy of detection in absolute quantification was diminished via evaluations of metal intensities on the single magnetic bead. The intrinsic proportion of fPSA in tPSA was successfully evaluated by direct use of the Pt to Au intensity ratio (Pt/Au ratio), exhibiting better differentiation between healthy and unhealthy, benign prostatic hyperplasia (BPH) and cancer individuals compared with solo fPSA or tPSA. We generated thresholds respectively for prostate disease differentiation, envisioning that this standard-free SMB nanoplatform would establish a standardized methodology with uniform criteria worldwide in cancer diagnosis, staging, and postoperative assessments.

12.
Front Public Health ; 10: 1066299, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36589974

RESUMEN

The ongoing COVID-19 pandemic has evolved beyond being a public health crisis as it has exerted worldwide severe economic impacts, triggering cascading failures in the global industrial network. Although certain powerful enterprises can remain its normal operation during this global shock, what's more likely to happen for the majority, especially those small- and medium-sized firms, is that they are experiencing temporary suspension out of epidemic control requirement, or even permanent closure due to chronic business losses. For those enterprises that sustain the pandemic and only suspend for a relatively short period, they could resume work and production when epidemic control and prevention conditions are satisfied and production and operation are adjusted correspondingly. In this paper, we develop a novel quantitative framework which is based on the classic susceptible-infectious-recovered (SIR) epidemiological model (i.e., the SIR model), containing a set of differential equations to capture such enterprises' reactions in response to COVID-19 over time. We fit our model from the resumption of work and production (RWP) data on industrial enterprises above the designated size (IEDS). By modeling the dynamics of enterprises' reactions, it is feasible to investigate the ratio of enterprises' state of operation at given time. Since enterprises are major economic entities and take responsibility for most output, this study could potentially help policy makers better understand the economic impact caused by the pandemic and could be heuristic for future prevention and resilience-building strategies against suchlike outbreaks of public health crises.


Asunto(s)
COVID-19 , Enfermedades Transmisibles , Humanos , COVID-19/epidemiología , Pandemias , Brotes de Enfermedades , Personal Administrativo
13.
Anal Chem ; 93(37): 12714-12722, 2021 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-34494424

RESUMEN

Early diagnosis, early isolation, and early treatment are efficient solutions to control the COVID-19 pandemic. To achieve the accurate early diagnosis of SARS-CoV-2, a multiplex detection strategy is required for the cross-validation to solve the problem of "false negative" of the existing gold standard assay. Here, we present a multicomponent nucleic acid assay platform for SARS-CoV-2 detection based on lanthanide nanoparticle (LnNP)-tagging strategy. For targeting SARS-CoV-2's RNA fragments ORF1ab gene, RdRp gene, and E gene, three LnNP probes can be used simultaneously to identify three sites in one sample through elemental mass spectrometry detection with limits of detection of 1.2, 1.3, and 1.3 fmol, respectively. With the multisite cross-validation, we envision that this multiplex and sensitive detection platform may provide an effective strategy for SARS-CoV-2 fast screening with a high accuracy.


Asunto(s)
COVID-19 , Elementos de la Serie de los Lantanoides , Nanopartículas , Humanos , Pandemias , ARN Viral/genética , SARS-CoV-2 , Sensibilidad y Especificidad
14.
ACS Sens ; 6(8): 2893-2901, 2021 08 27.
Artículo en Inglés | MEDLINE | ID: mdl-34269056

RESUMEN

The detection and monitoring of dichloroalkanes, which are typical chlorinated volatile organic compounds (CVOCs) with obvious biological toxicity, is of significance for environmental pollution and public health. Herein, a novel ozone-activated cataluminescence (CTL) sensor system based on silica nanospheres was developed for highly sensitive and fast quantification of dichloroalkanes. A typical CTL system coupled with a plasma-ozone-assist unit was designed for promoting the CTL response of dichloroalkanes. The ozone generated by plasma provides a new pathway of catalytic oxidation process, which accompanied by the CTL signal amplification of dichloroalkanes results in an enhanced CTL sensor system with improved limit of detection (1,2-dichloroethane: 0.04 µg mL-1, 1,2-dichloropropane: 0.03 µg mL-1) and benign selective performance under the interference of CO2, H2O, NO, NO2, SO2, CS2, and other common CVOCs. Moreover, a segmented CTL mechanism including co-adsorption of ozone and dichloroalkanes, thermal elimination, the ozonation route, and a luminous step was ratiocinated based on multiple characterizations and discussion. The proposed methodology and theory open up an attractive perspective for the analysis of less active volatile organic compounds.


Asunto(s)
Nanosferas , Ozono , Catálisis , Mediciones Luminiscentes , Dióxido de Silicio
15.
Front Oncol ; 11: 621353, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34094907

RESUMEN

BACKGROUND: HCC is one of the most common malignancies with an increasing incidence worldwide, especially in Asian countries. However, even though targeted cancer therapy drugs such as sorafenib and regorafenib are available, the overall outcome of HCC remains unsatisfactory. Thus, it is urgent to investigate the molecular mechanisms of HCC progression, so as to provide accurate diagnostic criteria and therapeutic targets. METHODS: RNA-seq data was used to identify and quantify circular RNAs (circRNAs). DESeq2 was used to identify the differentially expressed circRNAs. miRNA binding sites within circRNAs were identified by miRanda. Gene set enrichment analysis (GSEA) was conducted to predict the biological function of circRNAs. RESULTS: The differential expression analysis identified 107 upregulated and 95 downregulated circRNAs in HCC tissues. We observed that a differentially expressed circRNA (DE-circRNA), hsa_circ_0141900 was highly negatively correlated with its parental gene RAB1A (PCC < -0.6), which was also closely associated with mTOR signaling pathway. Moreover, we also constructed competing endogenous RNA (ceRNA) network to identify key circRNAs involved in HCC. Notably, hsa_circ_0002130 and hsa_circ_0008774 were highly correlated with the genes involved in gluconeogenesis and HNF3A pathway via the target genes, GOT2 and AR, suggesting that the two circRNAs might regulate these pathways, respectively. Survival analysis revealed that GOT2 was associated with favorable prognosis. Furthermore, high expression of hsa_circ_0002130 was found to inhibit tumor cell growth and promotes GOT2 expression. CONCLUSION: In summary, the circRNAs highlighted by the integrative analysis greatly improved our understanding of the underlying mechanism of circRNAs in HCC.

16.
Entropy (Basel) ; 22(6)2020 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-33286387

RESUMEN

The stock market is a complex system with unpredictable stock price fluctuations. When the positive feedback in the market amplifies, the systemic risk will increase rapidly. During the last 30 years of development, the mechanism and governance system of China's stock market have been constantly improving, but irrational shocks have still appeared suddenly in the last decade, making investment decisions risky. Therefore, based on the daily return of all a-shares in China, this paper constructs a dynamic complex network of individual stocks, and represents the systemic risk of the market using the average weighting degree, as well as the adjusted structural entropy, of the network. In order to eliminate the influence of disturbance factors, empirical mode decomposition (EMD) and grey relational analysis (GRA) are used to decompose and reconstruct the sequences to obtain the evolution trend and periodic fluctuation of systemic risk. The results show that the systemic risk of China's stock market as a whole shows a downward trend, and the periodic fluctuation of systemic risk has a long-term equilibrium relationship with the abnormal fluctuation of the stock market. Further, each rise of systemic risk corresponds to external factor shocks and internal structural problems.

17.
Anal Chem ; 92(24): 16105-16112, 2020 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-33275406

RESUMEN

Pancreatic cancer is one of the foremost malignant gastrointestinal tumors, with prognosis and postoperative prediction remaining challenging because of the lack of facile, sensitive diagnostic methods and a specific single biomarker. Combined-biomarker analysis which provides a promising strategy to conquer such dilemma still requires developments in methodologies to gain accurate and reliable outcomes with wash-/separation-free scenarios and minimal interferences. Herein, a multiplex single-particle homogeneous immunoassay was proposed by simultaneously evaluating three pancreatic cancer-related biomarkers. Owing to the excellent resolution and multielement detectors without mass spectra overlapping, single-particle ICP-MS simultaneously provided biomarkers (CA125, CEA, and CA199) with three to four order-of-magnitude linear ranges and low-level limits of detection from specific antibody-labeled noble metal nanoparticles (AuNPs, AgNPs, and PtNPs). By scrutinizing both intensity and frequency signals, the proposed method was successfully applied in patients' serological evaluation, with results correlating well with those measured by the clinical routine method. The proposed method provides a potential tool in risk assessment of disease recurrence and survival.


Asunto(s)
Biomarcadores de Tumor/sangre , Inmunoensayo/métodos , Neoplasias Pancreáticas/sangre , Humanos , Límite de Detección , Espectrometría de Masas , Nanopartículas del Metal/química
18.
Financ Res Lett ; 37: 101782, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33013238

RESUMEN

The proposal of "The Belt and Road" (The B&R) Initiative has promoted regional economic cooperation and financial integration. It is crucial to measure the volatility spillover effects among "The B&R" currency market. Results from the time-varying spillover model show that "The B&R" system spillover index reflects some sudden regional crises. Likewise, the spillover of RMB exchange rate is affected by internal financial reforms as well as external economic shocks. Further, the recent outbreak of the COVID-19 has disrupted this system and the influence of RMB.

19.
J Exp Clin Cancer Res ; 39(1): 20, 2020 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-31973767

RESUMEN

BACKGROUND: Exosomes play crucial roles in regulating the crosstalk between normal and cancer cells in the tumor microenvironment, and in regulating cancer proliferation, migration and invasion through their cargo molecules. METHODS: We analyzed the pro-invasiveness of exosomal circRNA-100,338 in HCC using the transwell invasion assay. The co-culture of human umbilical vein endothelial cells (HUVEC) and exosomes derived from HCC cell lines were used to evaluate the impact of HCC derived exosomes on HUVEC. Nude mice models were used to validate the findings in vitro. Clinically, quantitative RT-PCR was used to quantify the expression of serum exosomal circRNA-100,338 in HCC patients at both pre-surgery within one week and post-surgery within three weeks. RESULTS: We aim to investigate the pro-invasive role of exosomal circRNA-100,338 in HCC metastasis. We for the first time demonstrated that circRNA-100,338 was highly expressed in both highly metastatic HCC cells and their secreted exosomes. The transwell invasion assay showed that the overexpression or knockdown of exosomal circRNA-100,338 significantly enhanced or reduced the invasive abilities of HCC cells. Subsequently, in vitro and in vivo assays showed that exosomal circRNA-100,338 affected the cell proliferation, angiogenesis, permeability, and vasculogenic mimicry (VM) formation ability of human umbilical vein endothelial cells (HUVEC), and tumor metastasis. Furthermore, we also observed that the persistent high expression of exosomal circRNA-100,338 in serum of HCC patients who underwent curative hepatectomy may be a risk indicator of pulmonary metastasis and poor survival. CONCLUSIONS: Our findings indicated that metastatic ability of HCC cells could be enhanced by transferring exosomal circRNA-100,338 to recipient HUVECs, which could affect proangiogenic activity by regulating angiogenesis.


Asunto(s)
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Neovascularización Patológica/metabolismo , ARN Circular/genética , Animales , Carcinoma Hepatocelular/patología , Modelos Animales de Enfermedad , Humanos , Neoplasias Hepáticas/patología , Masculino , Ratones , Ratones Desnudos , Invasividad Neoplásica , Metástasis de la Neoplasia , Transfección
20.
Anal Chem ; 92(3): 2876-2881, 2020 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-31910615

RESUMEN

The most convenient method for the clinical routine analysis of disease biomarkers is homogeneous immunoassay, which minimizes the requirements for automation and time-/lab-consumption. Despite great success, because sample constituents are not removed by a separation or washing step, a major challenge in conducting homogeneous immunoassays for the practical application is the matrix effect-related inaccuracy. Herein, to guarantee an accurate quantification, a self-validated homogeneous immunoassay was proposed, by simultaneously scrutinizing both frequency and intensity of single gold nanoparticles. The two analytical modes of single particle inductively coupled plasma mass spectrometry (ICPMS) correlated well with each other, resulting in a self-validation mechanism for the accurate immunoassay. Both two modes of the proposed method provided linear ranges of 2 orders of magnitude and LODs of pM level. Thanks to the self-validated strategy and the high tolerance of the matrix effect of ICPMS, the proposed homogeneous immunoassay was successfully demonstrated in a series of human serum samples, with results in good accordance with clinical routine methods.


Asunto(s)
Antígeno Carcinoembrionario/sangre , Ensayo de Inmunoadsorción Enzimática , Oro/química , Nanopartículas del Metal/química , Reacciones Antígeno-Anticuerpo , Biomarcadores/sangre , Antígeno Carcinoembrionario/inmunología , Humanos , Espectrometría de Masas , Tamaño de la Partícula
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