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1.
J Hazard Mater ; 474: 134672, 2024 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-38815397

RESUMO

Room-temperature catalytic oxidation of formaldehyde (HCHO) has been extensively investigated due to its high efficiency, convenience, and environmental friendliness. Herein, nickel-iron layered double hydroxide (NiFe LDH) nanosheets were synthesized in-situ on a nickel foil (NF) using a facile one-step hydrothermal method, followed by the deposition of ultra-low content (0.069 wt%) of Pt nanoparticles through NaBH4 reduction. The resulting three-dimensional (3D) hierarchical Pt/NiFe-NF catalyst exhibited exceptional activity for the complete decomposition of formaldehyde to carbon dioxide (CO2) at room temperature (∼95 % conversion within 1 h), as well as remarkable cycling stability. The 3D porous structure of Pt/NiFe-NF provides fast transport channels for the diffusion of gas molecules, making the active catalyst surfaces more accessible. Moreover, abundant hydroxyl groups in NiFe LDH serve as adsorption centers for HCHO molecules to form dioxymethylene (DOM) and formate intermediates. Furthermore, electronic interactions between NiFe LDH and Pt enhance the adsorption and activation of O2 on Pt surfaces, leading to the complete decomposition of intermediates into non-toxic products. This work presents new insights into the design and preparation of Pt-based 3D hierarchical catalysts with surface-rich hydroxyl groups for the efficient removal of indoor HCHO.

2.
J Inflamm Res ; 17: 2977-2989, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38764494

RESUMO

Background: Some patients with COVID-19 rapidly develop respiratory failure or mortality, underscoring the necessity for early identification of those prone to severe illness. Numerous studies focus on clinical and lab traits, but only few attend to chest computed tomography. The current study seeks to numerically quantify pulmonary lesions using early-phase CT scans calculated through artificial intelligence algorithms in conjunction with clinical and laboratory helps clinicians to early identify the development of severe illness and death in a group of COVID-19 patients. Methods: From December 15, 2022, to January 30, 2023, 191 confirmed COVID-19 patients admitted to Xinhua Hospital Affiliated with Shanghai Jiao Tong University School of Medicine were consecutively enrolled. All patients underwent chest CT scans and serum tests within 48 hours prior to admission. Variables significantly linked to critical illness or mortality in univariate analysis were subjected to multivariate logistic regression models post collinearity assessment. Adjusted odds ratio, 95% confidence intervals, sensitivity, specificity, Youden index, receiver-operator-characteristics (ROC) curves, and area under the curve (AUC) were computed for predicting severity and in-hospital mortality. Results: Multivariate logistic analysis revealed that myoglobin (OR = 1.003, 95% CI 1.001-1.005), APACHE II score (OR = 1.387, 95% CI 1.216-1.583), and the infected CT region percentage (OR = 113.897, 95% CI 4.939-2626.496) independently correlated with in-hospital COVID-19 mortality. Prealbumin stood as an independent safeguarding factor (OR = 0.965, 95% CI 0.947-0.984). Neutrophil counts (OR = 1.529, 95% CI 1.131-2.068), urea nitrogen (OR = 1.587, 95% CI 1.222-2.062), SOFA score(OR = 3.333, 95% CI 1.476-7.522), qSOFA score(OR = 15.197, 95% CI 3.281-70.384), PSI score(OR = 1.053, 95% CI 1.018-1.090), and the infected CT region percentage (OR = 548.221, 95% CI 2.615-114,953.586) independently linked to COVID-19 patient severity.

3.
Water Res ; 257: 121648, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38663215

RESUMO

Reconstructing transient states presents significant challenges, particularly within complex pipe networks. These challenges arise due to nonlinear behaviours, inherent uncertainties in the system, and limitations in data availability. This work proposed a novel approach employing Physics-Informed Neural Networks (PINN) to reconstruct transient states in pipe networks, even with limited sensor data. To integrate the complex topology of pipe network systems into neural networks, the method integrates the PINN framework with an efficient elastic water column (EWC) model which can be simply formulated across diverse pipe network configurations. The results showed the proposed PINN method can accurately reconstruct the pressure and flow variation at unmonitored locations, even provided with noisy data at a limited number of locations. One of its advantages lies in its ability to effectively capture extreme values that hold potential significance for pipe infrastructure, providing a promising avenue for pipe failure analysis and enhanced safety management. Laboratory experiments have also been conducted to validate the efficacy and reliability of this method, thus further underlining its potential for real-world applications.


Assuntos
Redes Neurais de Computação , Pressão , Modelos Teóricos , Abastecimento de Água
4.
J Clin Ultrasound ; 51(7): 1242-1243, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37310175

RESUMO

① Gray scale ultrasound showed multiple hypoechoic masses of varying sizes in the right breast. The larger one was 1.8 × 0.7 cm (arrow), oval in shape, with clear boundaries, and lymphatic hilar-like structures. ② Color Doppler ultrasonography showed blood flow signals within the hypoechoic mass, and the larger (arrow) mass showed blood flow signals similar to lymphatic hilum. ③ Elastography showed the mass was soft and blue (short arrow) or green (long arrow) in texture, and the surrounding tissue was hard and red in texture. ④ Contrast-enhanced ultrasound showed that after 19 s of contrast agent injection, the whole breast showed a 'snowflake' high enhancement, but no enhancement was observed in local areas (arrow). ⑤ The ultrasound-guided puncture image clearly showed the puncture needle (arrow) insert into the hypoechoic mass for biopsy. ⑥ The arrow in the pathological image (HE, 20 × 10 times) showed tumor cells.


Assuntos
Técnicas de Imagem por Elasticidade , Linfoma , Humanos , Masculino , Ultrassonografia/métodos , Técnicas de Imagem por Elasticidade/métodos , Meios de Contraste , Agulhas , Linfoma/diagnóstico por imagem , Ultrassonografia Doppler em Cores/métodos
5.
Anticancer Drugs ; 34(1): 92-102, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36066384

RESUMO

Cancer patients often suffer from cancer symptoms, treatment complications and concomitant diseases and are, therefore, often treated with several drugs in addition to anticancer drugs. Whether such drugs, here denoted as 'concomitant drugs', have anticancer effects or interact at the tumor cell level with the anticancer drugs is not very well known. The cytotoxic effects of nine concomitant drugs and their interactions with five anti-cancer drugs commonly used for the treatment of colorectal cancer were screened over broad ranges of drug concentrations in vitro in the human colon cancer cell line HCT116wt. Seven additional tyrosine kinase inhibitors were included to further evaluate key findings as were primary cultures of tumor cells from patients with colorectal cancer. Cytotoxic effects were evaluated using the fluorometric microculture cytotoxicity assay (FMCA) and interaction analysis was based on Bliss independent interaction analysis. Simvastatin and loperamide, included here as an opioid agonists, were found to have cytotoxic effects on their own at reasonably low concentrations whereas betamethasone, enalapril, ibuprofen, metformin, metoclopramide, metoprolol and paracetamol were inactive also at very high concentrations. Drug interactions ranged from antagonistic to synergistic over the concentrations tested with a more homogenous pattern of synergy between simvastatin and protein kinase inhibitors in HCT116wt cells. Commonly used concomitant drugs are mostly neither expected to have anticancer effects nor to interact significantly with anticancer drugs frequently used for the treatment of colorectal cancer.


Assuntos
Antineoplásicos , Neoplasias Colorretais , Humanos , Células Tumorais Cultivadas , Antineoplásicos/farmacologia , Interações Medicamentosas , Sinvastatina
6.
Fish Shellfish Immunol ; 127: 918-924, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35863536

RESUMO

PAP (3'-phosphoadenosine 5'-phosphate) is a ubiquitous phosphoric acid and a natural inhibitor of the XRN (5'-3'exoribonuclease) family. It was proved to enter the nucleus through the retrograde signaling pathway and inhibit XRN2 to prevent the degradation of miRNA precursors, thus promoting the anti-oxidation miRNA level in Arabidopsis thaliana. Vitamin E (tocopherol) was proved to promote the accumulation of PAP in the plant, which facilitates PAP into the nucleus to accomplish its antioxidant function. However, the relationship between VE and PAP in animals is unclear. To identify the relationship between VE and PAP and to uncover the function of PAP in fish, we investigated the performance of VE and PAP in Nile tilapia by comparing the antioxidant indicators (SOD, GSH-Px, and CAT), the Keap1-Nrf2 signaling pathway, and the miRNA expression profiles. Results showed that the antioxidant effect of VE and PAP showed similar character either in tilapia liver or in serum: the activities of GSH-Px and CAT of both groups were significantly increased (P < 0.05); the SOD activity of the VE group was significantly increased (P < 0.05), and although the result of the PAP group was not so significant (P > 0.05), PAP improved the SOD level, too. The two groups also showed similar character in the tilapia liver; both did not significantly increase the liver δ-VE content (P > 0.05). However, VE significantly increased the content of α-VE and γ-VE (P < 0.05), while the PAP group was insignificant (P > 0.05). Feed with VE and intraperitoneal injection of PAPs reagent both increased the PAP content in the liver of tilapia, and the effect of the VE group was more significant (P < 0.05) than that of the PAP group (P > 0.05). Both groups reduced the expression of Keap1 and Cullin3 genes and improved the level of HO-1 gene expression, with the improved miRNA level of Nrf2. As a logical result, they decreased the expression of XRN1 and XRN2. By profile sequencing, we further identified some antioxidant closely related miRNAs shared in the VE and PAP groups, including miR-30, miR-24, miR-19b, and miR-100. By comparing the regulating mechanism of VE and PAP of feed supply and intraperitoneal injection, we proved that VE and PAP were closely related in fish; VE promoted the gathering of PAP. The latter retrograded into the nucleus of the fish liver to inhibit the expression of XRN genes and to up-regulate antioxidant miRNA levels as it does in plants. Only the PAP can accomplish the antioxidant activities, while VE promotes the process. Our study laid the foundation for the application of PAP as a new antioxidant agent in fish farming and benefit a further understanding of the VE antioxidant function in fish.


Assuntos
Ciclídeos , MicroRNAs , Ração Animal/análise , Animais , Antioxidantes/metabolismo , Ciclídeos/genética , Ciclídeos/metabolismo , Dieta , Suplementos Nutricionais , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , MicroRNAs/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Transdução de Sinais , Superóxido Dismutase/metabolismo , Vitamina E/metabolismo
7.
Water Res ; 221: 118828, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35841787

RESUMO

In water pipeline systems, monitoring and predicting hydraulic transient events are important to ensure the proper operation of pressure control devices (e.g., pressure reducing valves) and prevent potential damages to the network infrastructure. Simulating transient pressures using traditional numerical methods, however, require a complete model with known boundary and initial conditions, which is rarely able to obtain in a real system. This paper proposes a new physics-based and data-driven method for targeted transient pressure reconstruction without the need of having a complete pipe system model. The new method formulates a physics-informed neural network (PINN) by incorporating both measured data and physical laws of the transient flow in the training process. This enables the PINN to learn and explore hidden information of the hydraulic transient (e.g., boundary conditions and wave damping characteristics) that is embedded in the measured data. The trained PINN can then be used to predict transient pressures at any location of the pipeline. Results from two numerical and one experimental case studies showed a high accuracy of the pressure reconstruction using the proposed approach. In addition, a series of sensitivity analyses have been conducted to determine the optimal hyperparameters in the PINN and to understand the effects of the sensor configuration on the model performance.


Assuntos
Redes Neurais de Computação , Física , Água
8.
Bioengineered ; 13(3): 7134-7146, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35274595

RESUMO

Sepsis-induced myocardial dysfunction (SIMD) is associated with high morbidity and mortality rates; however, it lacks targeted therapies. Modulating cardiomyocyte autophagy maintains intracellular homeostasis during SIMD. Clemastine, a histamine receptor inhibitor, promotes autophagy and other effective biological functions. Nevertheless, the effect of clemastine on SIMD remains unclear. This study aimed to explore the underlying mechanism of clemastine in cardiomyocyte injury in cecum ligation and perforation (CLP)-induced rats and lipopolysaccharide (LPS)-stimulated H9c2 cells. Clemastine (10 mg/kg, 30 mg/kg, and 50 mg/kg) was intraperitoneally injected after 30 min of CLP surgery. Serum cTnI levels and the 7-day survival rate were evaluated. Echocardiograms and H&E staining were used to evaluate cardiac function and structure. TEM was used to detect the mitochondrial ultrastructure and autophagosomes. Clemastine significantly improved the survival rate and reduced cTnI production in serum. Clemastine ameliorated cellular apoptosis, improved mitochondrial ultrastructure both in vivo and in vitro, increased ATP content, decreased dynamin-related protein 1 (DRP1) expression, and decreased mitochondrial ROS levels. Additionally, clemastine treatment increased autophagosome concentration, LC3II/LC3I rate, and Beclin 1 expression. However, 3-methyladenine (3-MA), an autophagy inhibitor, could abolish the effect of clemastine on alleviating myocardial apoptosis. In conclusion, clemastine protected against cardiac structure destruction and function dysfunction, mitochondrial damage, apoptosis, and autophagy in vivo and in vitro. Moreover, clemastine attenuated myocardial apoptosis by promoting autophagy. This study provides a novel favorable perspective for SIMD therapy.


Assuntos
Cardiomiopatias , Sepse , Animais , Apoptose , Autofagia , Cardiomiopatias/tratamento farmacológico , Cardiomiopatias/etiologia , Clemastina/metabolismo , Clemastina/farmacologia , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Ratos , Sepse/complicações , Sepse/tratamento farmacológico , Sepse/metabolismo
9.
Curr Med Sci ; 41(4): 815-820, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34403107

RESUMO

OBJECTIVE: Mild encephalopathy with reversible splenial lesion (MERS) is associated with a variety of infections and anti-epileptic drug withdrawal. Here we report the clinical characteristics of H1N1 influenza A-associated MERS based on our experience of four pediatric cases. METHODS: A detailed retrospective analysis of four patients with H1N1 influenza A-associated MERS was performed at Guangzhou Women and Children's Medical Center. RESULTS: All patients exhibited mild influenza-like illness and seizures. Three patients presented with a new-onset seizure with fever after 5 years of age. 75% patients had altered mental status. For all four patients, influenza A (H1N1) viral RNA was detected in throat swab specimens at least twice. Brain magnetic resonance images revealed similar ovoid lesions in the corpus callosum, mainly in the splenium and for one patient in the splenium and genu of the corpus callosum. Only one patient had an abnormal electroencephalogram tracing. Cells and protein in the cerebrospinal fluid were normal in all patients. All patients received oseltamivir and one patient received intravenous immunoglobulin. As a result, all patients fully recovered after 2 months and showed no neurologic sequelae at discharge. CONCLUSION: This case series provides insight towards clinical features of H1N1 influenza A-associated MERS.


Assuntos
Encefalopatias/diagnóstico , Encéfalo/diagnóstico por imagem , Corpo Caloso/diagnóstico por imagem , Vírus da Influenza A Subtipo H1N1/patogenicidade , Encéfalo/fisiopatologia , Encefalopatias/diagnóstico por imagem , Encefalopatias/fisiopatologia , Encefalopatias/virologia , Criança , Pré-Escolar , Corpo Caloso/fisiopatologia , Feminino , Humanos , Influenza Humana/complicações , Influenza Humana/diagnóstico , Influenza Humana/fisiopatologia , Influenza Humana/virologia , Imageamento por Ressonância Magnética , Masculino
10.
J Hazard Mater ; 416: 125745, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33866294

RESUMO

Exploring nitrogen-containing extractants for recovering hazardous minor actinides that are workable in solutions of high acidity has been a challenge in nuclear waste treatment. Herein, we report our findings that 2,6-bis-triazolyl-pyridine (PyTri), which is ineffective as a hydrophobic ligand for minor actinide separation, turns into an excellent extractant that exhibits unexpectedly high efficiency and selectivity (SFAm/Eu = 172, 1 M HNO3) when attaching to pillar[5]arene platform. Surprisingly, the distribution ratio of Am(III) (DAm) is 4300 times higher than that of the acyclic PyTri ligand. The solvent extraction performance of this pillar[5]arene-achored PyTri not only far exceeds the best known pillar[5]arene ligands reported to date, but also stays comparable to other reported outstanding extractants. Slope analysis indicates that each P[5]A-PyTri can bind two metal ions, which is further corroborated by spectroscopic characterizations. Thermodynamic studies imply that the extraction process is exothermic and spontaneous in nature. Complexation investigation via EXAFS technique and DFT calculations strongly suggest that each Eu(III) ion is coordinated to three PyTri arms through a nine-coordination mode. This work provides a N-donor extractant that can operate at high acidity for minor actinide partitioning and implicates a promising approach for transforming poor extractants into superior ones.

11.
Am J Transl Res ; 12(10): 6290-6301, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33194030

RESUMO

Severe acute pancreatitis (SAP) contributes to multiple organ dysfunction and intestine is one of the most susceptible targets. This study aims to explore the role of C3a/C3aR axis in SAP-induced intestinal barrier injury. Adult male Sprague Dawley rats were randomly divided into control, SAP, C3aRA (0.06 mg/kg) and C3aRA (0.12 mg/kg) groups. SAP rat models were established by retrograde injection of 3.5% sodium taurocholate solutions into pancreatic ducts. Histopathological changes and dysfunction in pancreatitis and intestine were measured by hematoxylin and eosin (H&E) staining and detection of amylase (AMY), lipase (LIPA), endotoxins and diamine oxidase (DAO) levels in serum. Cell apoptosis was evaluated by TUNEL assay and western blot analysis. In addition, the expressions of caudin-1, caudin-2, occludin and ZO-1 were detected by western blot assay and immunohistochemical staining. Inflammatory cytokines and oxidative stress levels in SAP rats were determined. The C3a/C3aR expression was increased in pancreatic and intestinal tissues of successfully established SAP rat models. C3a receptor antagonist (C3aRA) alleviated pancreatic and intestinal pathological lesions and dysfunction induced by SAP. C3aRA inhibited cell apoptosis and promoted the expressions of caudin-1, caudin-2, occludin and ZO-1 in intestinal tissues. Moreover, C3aRA repressed inflammatory cytokines by reduction of TNF-α, IL-1ß, IL-6 and MCP-1 levels, and ameliorated oxidative stress through regulation of ROS, MPO and SOD activity in rats with SAP-induced intestinal barrier injury. Our findings suggested that inhibition of C3a/C3aR axis diminished pancreatic damage and SAP-induced intestinal barrier injury in vivo, which may provide a new therapeutic strategy for SAP-induced intestinal injury.

12.
Anal Chim Acta ; 1126: 1-6, 2020 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-32736712

RESUMO

A novel reverse transcription-based loop-mediated isothermal amplification (LAMP) strategy for miRNA detection has been developed. This method consists of two stem-loop probes inspired by the dumbbell-shaped amplicons and inner primers used in conventional LAMP reactions. Termed "terminal hairpin formation and self-priming" (THSP), this reaction incorporates phosphorothioated (PS) modifications to achieve DNA folding and extension without primers. The final signal is monitored by a sequence-specific detection probe, which minimizes the background noise. We suggest that our rapid, facile, and reliable LAMP method will be a promising candidate for detecting miRNA in biomedical applications.


Assuntos
MicroRNAs , Transcrição Reversa , Primers do DNA , MicroRNAs/genética , Técnicas de Diagnóstico Molecular , Técnicas de Amplificação de Ácido Nucleico , Sensibilidade e Especificidade
13.
Fish Shellfish Immunol ; 106: 28-35, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32707297

RESUMO

MiR-155 is reported as immune regulated miRNA in mammalian corresponding to immunity, antibacterial and antiviral effects regulation. However, the roles and mechanisms of the miRNA have remained largely undefined. We herein comprehensively investigated the functions of miR-155 in vitro and in vivo by miR-155 mimics, agomir and antagomir in Cyprinus carpio and Ictalurus punctatus, with the target genes in the SOSC1 pathway certified in I. punctatus via luciferase reporter assays. Results showed that the miR-155 regulated the expressions of cytokines, including TNF-α, IFN-γ, IL-1ß, IL-6 and IL-10. Further research confirmed SOSC1 as one of the targets of the miRNA, and the JAK1/STAT3/SOSC1 signal pathway involved in the miR-155 effects on the expression of immune cytokines as well. Additionally, the changes of TLR2 in fish may also be related to miR-155 along with its target SOCS1, and the TLR2/MyD88 pathway may partly participate in the effects of the miR-155 on the cytokines. The research here confirmed that the miR-155 can regulate cytokines expression by SOSC1 signal pathways of fish in vitro and in vivo, which would provide resources for understanding and studying about immune regulation in fish.


Assuntos
Carpas/genética , Citocinas/genética , Proteínas de Peixes/genética , Regulação da Expressão Gênica/imunologia , Ictaluridae/genética , MicroRNAs/genética , Animais , Carpas/imunologia , Citocinas/imunologia , Proteínas de Peixes/imunologia , Ictaluridae/imunologia , MicroRNAs/imunologia , Transdução de Sinais/imunologia
14.
J Pharm Anal ; 10(2): 97-101, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32292623

RESUMO

The recent pneumonia outbreak caused by a novel coronavirus (SARS-CoV-2) is posing a great threat to global public health. Therefore, rapid and accurate identification of pathogenic viruses plays a vital role in selecting appropriate treatments, saving people's lives and preventing epidemics. It is important to establish a quick standard diagnostic test for the detection of the infectious disease (COVID-19) to prevent subsequent secondary spread. Polymerase chain reaction (PCR) is regarded as a gold standard test for the molecular diagnosis of viral and bacterial infections with high sensitivity and specificity. Isothermal nucleic acid amplification is considered to be a highly promising candidate method due to its fundamental advantage in quick procedure time at constant temperature without thermocycler operation. A variety of improved or new approaches also have been developed. This review summarizes the currently available detection methods for coronavirus nucleic acid. It is anticipated that this will assist researchers and clinicians in developing better techniques for timely and effective detection of coronavirus infection.

15.
J Pharm Anal ; 9(4): 217-226, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31452959

RESUMO

MicroRNAs (miRNAs) are a family of endogenous, small (approximately 22 nucleotides in length), noncoding, functional RNAs. With the development of molecular biology, the research of miRNA biological function has attracted significant interest, as abnormal miRNA expression is identified to contribute to serious human diseases such as cancers. Traditional methods for miRNA detection do not meet current demands. In particular, nanomaterial-based methods, nucleic acid amplification-based methods such as rolling circle amplification (RCA), loop-mediated isothermal amplification (LAMP), strand-displacement amplification (SDA) and some enzyme-free amplifications have been employed widely for the highly sensitive detection of miRNA. MiRNA functional research and clinical diagnostics have been accelerated by these new techniques. Herein, we summarize and discuss the recent progress in the development of miRNA detection methods and new applications. This review will provide guidelines for the development of follow-up miRNA detection methods with high sensitivity and specificity, and applicability to disease diagnosis and therapy.

16.
Anal Chim Acta ; 1077: 208-215, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31307711

RESUMO

A novel microRNA (miRNA) quantification method has been developed using one-step rolling circle-quantitative PCR (RC-qPCR) analysis. Vent (exo-) DNA polymerase is firstly utilized to combine a rolling circle amplification (RCA) and qPCR in one step with high sensitivity and specificity in our RC-qPCR assay. Before performing the RC-qPCR, a padlock probe is ligated only when it is perfectly hybridized with miRNA. This ligation-based miRNA assay is highly specific for mature miRNAs, discriminating among related miRNAs that differ by as little as one nucleotide. It exhibits a dynamic range of seven orders of magnitude with a detection limit of 500 aM, and could be also used for the quantification of other small RNA molecules such as short interfering RNAs (siRNAs).


Assuntos
MicroRNAs/análise , Reação em Cadeia da Polimerase/métodos , Linhagem Celular Tumoral , DNA/química , DNA/genética , Sondas de DNA/química , Sondas de DNA/genética , DNA Polimerase Dirigida por DNA/química , Humanos , Limite de Detecção , MicroRNAs/genética , Hibridização de Ácido Nucleico , Sensibilidade e Especificidade , Thermococcus/enzimologia
17.
Luminescence ; 34(8): 823-829, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31290225

RESUMO

A simple microRNA (miRNA) aptasensor has been developed combining the conformational switch of a streptavidin aptamer and isothermal strand displacement amplification. In the presence of its target miRNA, the allosteric molecular beacon (aMB) probe immobilized on the plate can be 'switched on' and release the streptavidin aptamer. At the same time, Klenow fragment (3'→5' exo-) is utilized to initiate DNA-strand displacement, which starts the target recycling process. Based on the aptamer' high binding affinity and subsequent catalytic chemiluminescence (CL) detection, this CL strategy is highly specific in distinguishing mature miRNAs in same family. It exhibits a dynamic range of four orders of magnitude with a detection limit of 50 fM, and shows great potential for miRNA-related clinical practices and biochemical research.


Assuntos
Aptâmeros de Nucleotídeos/química , Luminescência , MicroRNAs/análise , Conformação de Ácido Nucleico
18.
Mikrochim Acta ; 186(7): 463, 2019 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-31230126

RESUMO

A novel chemiluminescence resonance energy transfer (CRET) system was developed and combined with a structure-switching aptamer for the highly sensitive detection of platinum. Platinum was chosen as a model analyte to demonstrate the generality of the new CRET system. This aptameric platform consisted of a streptavidin labeled aptamer against platinum and a streptavidin-coated magnetic bead for the selective separation of platinum-bound aptamer. The platinum-aptamer probe contained several guanine (G) bases bound to the 3,4,5-trimethoxyphenyl-glyoxal (TMPG) donor group at the 5' end, a fluorescent acceptor (6-carboxy-2',4,7,7'-tetrachlorofluorescein, TET) at the 3' end, and a streptavidin aptamer sequence in which several base pairs were replaced by the G-G mismatch to induce the platinum-oligonucleotide coordination. The chemiluminescence (CL) generated by TMPG/G bases is transferred to the acceptor (TET). In the presence of platinum, the platinum-aptamer probe was folded such that the G bases at the 5' end and TET at the 3' were in close proximity. The complex was separated using streptavidin-coated magnetic beads by the addition of TMPG to form the TMPG/G bases complex. The ultraweak CL from the TMPG/G bases was strongly enhanced by TET. This novel CRET-based method can be easily performed with high limit of detection (50 ng·mL-1) and selectivity over other metal ions. This technique provides a novel method for simple, fast, and convenient point-of-care diagnostics for monitoring proteins and metal ions. Graphical abstract Schematic presentation of chemiluminescence resonance energy transfer (CRET) detection of platinum(II) by Pt-base pair coordination to the aptamer. TMPG: 3,4,5-trimethoxyphenyl-glyoxal, fluorophore TET: 6-carboxy-2',4,7,7'-tetrachlorofluorescein.


Assuntos
Cisplatino/sangue , Medições Luminescentes/métodos , Platina/sangue , Animais , Aptâmeros de Nucleotídeos/química , Transferência de Energia , Fluoresceínas/química , Corantes Fluorescentes/química , Glioxal/análogos & derivados , Guanina/química , Limite de Detecção , Luminescência , Fenômenos Magnéticos , Ratos Sprague-Dawley , Estreptavidina/química
19.
Anal Chim Acta ; 1050: 154-160, 2019 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-30661583

RESUMO

A novel real-time polymerase chain reaction (qPCR) platform for the simple and robust detection of platinum is described for the first time. Compared with conventional qPCR, a helper template, which is related to the active template for performing qPCR, was introduced in our helper qPCR system. Several guanine (G) bases were introduced in the helper template to obtain a platinum-responsive on/off switch based on G-Pt-G coordination. Because of the helper template, a slight change in platinum concentration would significantly change the signal in the qPCR. This novel helper qPCR technique easily detects platinum with high sensitivity (1 ng/mL) and selectivity over other metal ions. Therefore, it will be a promising technique for the detection of platinum in biomedical and environmental samples.


Assuntos
DNA/química , Platina/análise , Platina/química , Reação em Cadeia da Polimerase em Tempo Real
20.
Mol Immunol ; 101: 585-596, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29887504

RESUMO

Although participation of IL-6 in lung inflammation has been widely elucidated, the transcriptional regulation of its generation in alveolar type II cells stimulated by TNF-α remain unclear. Here, we find that TNF-α significantly induces IL-6 production, and TNF-α induction of IL-6 is mainly regulated at transcriptional level. Upon stimulated by TNF-α, Activator Protein-1 (AP-1)-mediated transcriptional activity is apparently increased in alveolar type II epithelial cells, which might be derived from elevated phosphorylation of JNK and subsequent activation of c-Jun. Either down-regulation of c-Jun or the AP-1 site mutation leads to significant reduction of IL-6 expression. In contrast, ectopic expression of c-Jun notably increases IL-6 generation. So, c-Jun, one of the AP-1 family members, plays a pivotal role in TNF-α-induced IL-6 generation. CCAAT/enhancer binding protein δ (C/EBPδ) expression is significantly amplified by TNF-α, which may contribute to the rise of C/EBP activity in alveolar type II cells. C/EBPδ shRNA treatment results in attenuation of IL-6 expression in the cells, which is consistent with data by introduction of mutations into the C/EBP site in the promoter. However, overexpression of C/EBPδ greatly increases the IL-6 promoter activity. In addition, data regarding another transactivator in the family-C/EBPß show that it does not affect IL-6 production. We also find that the IKK/NF-κB p65 pathway is activated in TNF-α-treated alveolar type II epithelial cells, and plays an essential role in positive regulation of IL-6 expression in TNF-α-treated alveolar type II epithelial cells via knockdown or forced expression of NF-κB p65, or elimination of κB sites in the IL-6 promoter. Notably, IL-6 promoter-driven luciferase production in primary alveolar type II epithelial cells can also be increased by the ectopic expression of c-Jun, C/EBPδ, and NF-κB p65, respectively. Collectively, our data provide insights into molecular mechanism involved in IL-6 expression in alveolar type II epithelial cells on TNF-α treatment, which provides a theoretical basis for specific inhibition of IL-6 production at the transcriptional level.


Assuntos
Células Epiteliais Alveolares/metabolismo , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Quinase I-kappa B/metabolismo , Interleucina-6/genética , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas c-jun/metabolismo , Fator de Transcrição AP-1/metabolismo , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Células Epiteliais Alveolares/efeitos dos fármacos , Animais , Sítios de Ligação , Linhagem Celular , Regulação para Baixo/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Regiões Promotoras Genéticas
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