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1.
J Cancer Res Clin Oncol ; 150(4): 184, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38598014

RESUMO

BACKGROUND: Extracellular vesicles (EVs) can mediate cell-to-cell communication and affect various physiological and pathological processes in both parent and recipient cells. Currently, extensive research has focused on the EVs derived from cell cultures and various body fluids. However, insufficient attention has been paid to the EVs derived from tissues. Tissue EVs can reflect the microenvironment of the specific tissue and the cross-talk of communication among different cells, which can provide more accurate and comprehensive information for understanding the development and progression of diseases. METHODS: We review the state-of-the-art technologies involved in the isolation and purification of tissue EVs. Then, the latest research progress of tissue EVs in the mechanism of tumor occurrence and development is presented. And finally, the application of tissue EVs in the clinical diagnosis and treatment of cancer is anticipated. RESULTS: We evaluate the strengths and weaknesses of various tissue processing and EVs isolation methods, and subsequently analyze the significance of protein characterization in determining the purity of tissue EVs. Furthermore, we focus on outlining the importance of EVs derived from tumor and adipose tissues in tumorigenesis and development, as well as their potential applications in early tumor diagnosis, prognosis, and treatment. CONCLUSION: When isolating and characterizing tissue EVs, the most appropriate protocol needs to be specified based on the characteristics of different tissues. Tissue EVs are valuable in the diagnosis, prognosis, and treatment of tumors, and the potential risks associated with tissue EVs need to be considered as therapeutic agents.


Assuntos
Líquidos Corporais , Vesículas Extracelulares , Neoplasias , Humanos , Carcinogênese , Comunicação Celular , Microambiente Tumoral
2.
J Pharm Biomed Anal ; 243: 116080, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38479306

RESUMO

Cancer antigen 125 (CA125) is pivotal as a tumor marker in early ovarian cancer prevention and diagnosis. In this work, we introduced an ultrasensitive label-free electrochemical immunosensor tailored for CA125 detection, leveraging nanogold-functionalized copper-cobalt oxide nanosheets (CuCo-ONSs@AuNPs) as nanocomposites. For the inaugural application, copper-cobalt oxide nanosheets delivered the requisite DPV electrochemical response for the immunosensors. Their large specific surface area and commendable electrical conductivity amplify electron transfer and enable significant gold nanoparticle loading. Concurrently, AuNPs offer a plethora of active sites, facilitating easy immobilization of biomolecules via the bond between amino groups and AuNPs. We employed scanning electron microscopy, transmission electron microscopy, and x-ray photoelectron spectroscopy to characterize the nanomaterials' surface morphology and elemental composition. The electrochemical sensor response signals were ascertained using differential pulse voltammetry. Under optimal conditions, the immunosensor exhibited a linear detection range from 1×10-7 U/mL to 1×10-3 U/mL and a detection limit of 3.9×10-8 U/mL (S/N=3). The proposed label-free electrochemical immunosensor furnishes a straightforward, dependable, and sensitive approach for CA125 quantification and stands as a promising method for clinical detection of other tumor markers.


Assuntos
Técnicas Biossensoriais , Cobalto , Nanopartículas Metálicas , Nanocompostos , Neoplasias , Óxidos , Ouro/química , Técnicas Biossensoriais/métodos , Cobre , Limite de Detecção , Técnicas Eletroquímicas/métodos , Antígeno Ca-125 , Nanopartículas Metálicas/química , Imunoensaio/métodos , Biomarcadores Tumorais , Nanocompostos/química
3.
Talanta ; 272: 125606, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38394747

RESUMO

Carbohydrate antigen 199 (CA199) is the most sensitive marker reported for pancreatic cancer, and it is a difficult task to develop a highly sensitive assay for CA199. During the experiment, a ratiometric electrochemical immunosensor for quantitative analysis of CA199 was prepared for NiCo@Fc-MWCNTs-LDH as the electrode sensing surface and 3D-rGOF@Ag/Au as the label of Ab2. NiCo@Fc-MWCNTs-LDH not only provide the required signal for the immunosensor, but also have a layered structure to obtain a large specific surface area, which can provide more sites for the placement of biological molecules. rGOF has the advantages of large specific surface area and high porosity, which can adsorb Ag electrochemical probe through redox reaction. The modification of gold nanoparticles can not only enhance the electrical conductivity of nano-composites, but also immobilize more biomolecules to improve the sensitivity of electrochemical sensors. With the beefing up of CA199 concentration, the oxidation peak current of Ag increases and the oxidation peak current of Fc-COOH decreases. The ratio (y = IAg/IFc-COOH) of two different signals was linear with the logarithm of CA199 concentration in a certain value range. Under optimal conditions, the immunosensor showed excellent performance in the concentration range of 0.0001 U/mL to 10 U/mL, and the detection limit was 5.55 × 10-4 U/mL. The strategy could clearly discriminate between matched and mismatched targets, demonstrating high specifificity. This approach further detects CA199 in human plasma to differentiate pancreatic cancer patients from healthy individuals with high accuracy. This method also provided a new idea for the ultrasensitive quantitative detection of other biomarkers.


Assuntos
Técnicas Biossensoriais , Grafite , Nanopartículas Metálicas , Neoplasias Pancreáticas , Humanos , Ouro/química , Técnicas Biossensoriais/métodos , Nanopartículas Metálicas/química , Técnicas Eletroquímicas/métodos , Imunoensaio/métodos , Biomarcadores Tumorais , Neoplasias Pancreáticas/diagnóstico , Limite de Detecção , Grafite/química
4.
Urol Oncol ; 42(5): 133-143, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38418270

RESUMO

Early detection, diagnosis, and treatment take on critical significance in preventing and treating bladder cancer. As indicated by numerous studies, survivin can serve as a biomarker of bladder cancer, whereas the results of a wide variety of studies have been controversial. This paper is to assess the accuracy of survivin in the diagnosis of bladder cancer by a meta-analysis. The studies regarding the diagnosis of bladder cancer using survivin were systematically retrieved from the CNKI, WanFang, CBM, VIP, Web of science, cochrane library and pubmed were extracted, and the literature quality was assessed. Meta-analysis was conducted using STATA 16.0 MP. 2,082 relevant studies were searched, and 40 studies were finally covered for meta-analysis. The pooled specificity and pooled sensitivity of survivin mRNA was 0.95 (95%CI: 0.91, 0.97) and 0.94 (95%CI: 0.88, 0.97). The pooled specificity and pooled sensitivity of survivin protein reached 0.95 (95%CI: 0.90, 0.97) and 0.87 (95%CI: 0.78, 0.92). The pooled positive likelihood ratio, pooled negative likelihood ratio, the area under the curve, and diagnostic odds ratio for survivin mRNA reached 17.7 (95%CI: 10.3, 30.6), 0.07 (95%CI: 0.04, 0.12), 0.98 (95%CI: 0.97, 0.99) and 266 (95%CI: 114, 621), respectively. For survivin protein was 16.4 (95%CI: 7.9, 33.9), 0.14 (95%CI: 0.08, 0.24), 0.97 (95%CI: 0.95, 0.98) and 117 (95%CI: 38, 357), respectively. Survivin takes on great significance in diagnosing bladder cancer. However, due to some limitations in the number and quality of covered studies, this conclusion should be validated through additional higher quality clinical studies.


Assuntos
Neoplasias da Bexiga Urinária , Humanos , Survivina , Biomarcadores , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/genética , RNA Mensageiro/genética , Razão de Chances
5.
Talanta ; 269: 125412, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37984234

RESUMO

A "signal-on" electrochemiluminescence (ECL) immunosensor has been proposed for detecting carbohydrate antigen 153 (CA153) based on the dual MOFs sandwich strategy. The conductive and porous substrate consisting of 1T-MoS2 and two-dimensional conductive metal-organic framework (MOF, Ni-HAB) was anchored onto the glassy carbon electrode (GCE) to label the capture antibody (Ab1), and the luminescence-functionalized MOF (Ru(bpy)32+@UiO-66-NH2) was utilized to immobilize the detection second antibody (Ab2) to construct a "signal-on" responsive sandwich-type electrochemiluminescence immunoassay. Meanwhile, tripropylamine (TPA) acts as the co-reactant and provides a luminescence system for Ru(bpy)32+@UiO-66-NH2. The luminescence-functionalized MOFs showed excellent ECL activity owing to the tunable structure of MOFs. The remarkable enhancement in ECL intensity was obtained by the immunoreaction of antigen and antibody. Under the optimized conditions, the biosensor exhibited a detection limit of 0.0001 U mL-1 (S/N = 3) with a wide range from 0.001 to 50 U mL-1. The proposed ECL immunosensor was applicable for detecting human serum samples with a recovery of 99.83 ∼ 101 % (RSD < 5 %). This work demonstrates that the advantage of multifunctional MOFs could be applied to construct highly selective ECL immunosensor, and it may facilitate the diagnosis of breast cancer in clinics.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Estruturas Metalorgânicas , Compostos Organometálicos , Humanos , Molibdênio , Imunoensaio/métodos , Técnicas Biossensoriais/métodos , Estruturas Metalorgânicas/química , Biomarcadores Tumorais , Compostos Organometálicos/química , Anticorpos , Medições Luminescentes/métodos , Técnicas Eletroquímicas/métodos , Limite de Detecção , Nanopartículas Metálicas/química
6.
Bioelectrochemistry ; 156: 108613, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37995504

RESUMO

Cancer antigen 125 (CA125)1 is the most important biological screening indicator used to monitor epithelial ovarian cancers, and it plays a vital role in distinguishing ovarian cancers from benign diseases. Biosensors show great potential in the analysis and detection of disease markers. In this study, we designed electrochemical sensors based on three-dimensional amino-functionalized reduced graphene oxide (3D-rGOF-NH2),2 MgAl layered double hydroxide nanocomposites containing ordered mesoporous carbon (CMK-3),3 and ferrocene carboxylic acids(Fc-COOH)4for the detection of CA125. 3D-rGOF-NH2 possesses good conductivity, a large surface area, and high porosity, enabling more immobilized nanoparticles to be deposited on its surface with excellent stability. CMK-3@Fc@MgAl-LDH nanocomposite was used as a carrier to enhance the immobilization of antibodies and the loading of Fc, conductors to enhance conductivity, and enhancers to gradually amplify the signal of Fc. The surface morphology, elemental composition, and surface groups of the materials were characterized using scanning electron microscopy (SEM),5 transmission electron microscopy (TEM),6 and X-ray diffraction (XRD)7 techniques. The response signal of the electrochemical sensor was measured by DPV. Under the optimal conditions, the electrochemical sensor obtained a linear detection range of 0.01 U/mL-100 U/mL with a detection limit of 0.00417 U/mL.


Assuntos
Técnicas Biossensoriais , Grafite , Nanopartículas Metálicas , Nanocompostos , Humanos , Antígeno Ca-125 , Técnicas Biossensoriais/métodos , Anticorpos Imobilizados/química , Imunoensaio/métodos , Nanocompostos/química , Grafite/química , Técnicas Eletroquímicas/métodos , Limite de Detecção , Nanopartículas Metálicas/química , Ouro/química
7.
Sci Rep ; 13(1): 18003, 2023 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-37865650

RESUMO

Routing and security are the two main prerequisites for ensuring the correct operation of wireless networks. The importance of these cases doubles in wide networks such as IoT. This paper presents an algorithm to improve Secure Routing in IoT called SRAIOT. This algorithm uses a hierarchical structure to determine the connections between network components and data transfer routing. In SRAIOT, the network structure is managed hierarchically and through SDN. For this purpose, the IoT network is first divided into a set of subnets using the SDN solution, communication control and authentication are managed using the controller nodes of each subnet. The communication between two objects (located in different subnets) will be possible if their identity is confirmed through the controller nodes related to them. On the other hand, in order to identify the sources of attacks and network security threats, the controller nodes in each subnet monitor the network traffic pattern using an ensemble learning model and identify possible attacks in their subnet. The performance of SRAIOT was tested in the simulation, and the results were compared with previous methods. The results of these tests show that SRAIOT improves network performance regarding routing and detecting attacks.

8.
Nutr Metab Cardiovasc Dis ; 33(12): 2464-2470, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37798231

RESUMO

BACKGROUND AND AIMS: Hyperuricemia has become a vital public health problem affecting the health of residents. The visceral fat area (VFA) is closely related to many chronic diseases. However, the association between VFA and hyperuricemia within the Chinese adult population remains nebulous. The aim of the research is to assess the relationship between VFA and serum uric acid levels. METHODS AND RESULTS: From June 2020 to June 2021, a total of 340 Chinese adults (240 in the control group and 100 in the hyperuricemia group) were recruited from the physical examination center of Hongqi Hospital Affiliated to Mudanjiang Medical University. General demographic characteristics were collected by questionnaire. VFA was measured by a body composition analyzer, and serum biochemical indices were detected by clinical laboratory. VFA in the hyperuricemia group was higher than in the control group (P<0.05). Further, VFA demonstrated a positive correlation with serum uric acid level (rs = 0.370, P<0.001). To further explore this relationship, we divided the VFA into quartiles (<P25, P25-P50, P50-P75, ≥P75). Upon comparison with the <P25 group, we found the VFA in the P25-P50, P50-P75, and ≥P75 groups to be associated with a substantially escalated risk of hyperuricemia, even after adjusting for age, gender, body weight, fasting plasma glucose, calcium, alanine transaminase, urea, alkaline phosphatase, and γ-glutamyltransferase. The OR and 95% CI were 2.547 (1.023, 6.341), 3.788 (1.409, 10.187) and 3.723 (1.308, 10.595), respectively (P<0.05). CONCLUSION: VFA has a positive correlation with serum uric acid levels and may serve as a crucial predictive marker for hyperuricemia.


Assuntos
Hiperuricemia , Ácido Úrico , Humanos , Adulto , Estudos Transversais , Gordura Intra-Abdominal , Hiperuricemia/diagnóstico , Hiperuricemia/epidemiologia , População do Leste Asiático
9.
Mikrochim Acta ; 190(9): 366, 2023 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-37615746

RESUMO

The excessive utilization of antibiotics has led to significant water contamination and posed severe threats to human well-being. Consequently, the pressing imperative to identify antibiotics in the environment arises. In this study, we have successfully synthesized a hollow PCN-222 MOF distinguished by its substantial surface area and abundant functional groups, particularly the porphyrin cores. To augment the electrical conductivity of the hollow PCN-222 (HPCN-222), gold (Au) particles were incorporated within the porphyrin core using a fundamental hydrothermal method. This modification facilitated the effective immobilization of aptamer strands through π-π stacking and electrostatic interactions. As a result, the Au@HPCN-222 composite demonstrated exceptional efficacy as a substrate for immobilizing the aptamer (Apt) onto the GCE surface. By employing differential pulse voltammetry (DPV) we successfully achieved the detection of chloramphenicol (CAP) with a remarkably low limit of detection of 0.0138 ng mL-1 and the peak DPV currents at 0.18 V (vs. Ag/AgCl) were used for calibration. Furthermore, this aptasensor exhibited high selectivity and reproducibility.


Assuntos
Cloranfenicol , Porfirinas , Humanos , Reprodutibilidade dos Testes , Antibacterianos , Calibragem , Oligonucleotídeos
10.
Colloids Surf B Biointerfaces ; 228: 113419, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37393700

RESUMO

Paclitaxel is one of the most effective chemotherapeutic drugs which processes the obvious curative effect for a broad range of cancers including breast, ovarian, lung, and head & neck cancers. Though some novel paclitaxel-loaded formulations have been developed, the clinical application of the paclitaxel is still limited due to its toxicity and solubility issues. Over the past decades, we have seen rapid advances in applying nanocarriers in paclitaxel delivery systems. The nano-drug delivery systems offer unique advantages in enhancing the aqueous solubility, reducing side effects, increasing permeability, prolonging circulation half-life of paclitaxel. In this review, we summarize recent advances in developing novel paclitaxel-loaded nano delivery systems based on nanocarriers. These nanocarriers show great potentials in overcoming the disadvantages of pure paclitaxel and as a result improving the efficacy.


Assuntos
Nanopartículas , Neoplasias , Humanos , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Sistemas de Liberação de Fármacos por Nanopartículas , Medicina de Precisão , Sistemas de Liberação de Medicamentos , Neoplasias/tratamento farmacológico , Linhagem Celular Tumoral
11.
Anal Biochem ; 676: 115233, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37433362

RESUMO

Exosomes derived from lung cancer typically contain the genetic information of the donor cells. Therefore, exosomes contribute to early diagnosis, treatment effectiveness evaluation, and prognosis assessment of cancer. Based on the biotin-streptavidin system and MXenes nanomaterial, a dual-effect amplification method had been developed to construct an ultrasensitive colorimetric aptasensor for detecting exosomes. MXenes can enhance the loading of aptamer and biotin as the high specific surface area. Biotin-streptavidin system can increase the amount of horseradish peroxidase-linked (HRP-linked) streptavidin, considerably boosting the color signal of the aptasensor. The proposed colorimetric aptasensor exhibited excellent sensitivity, with a detection limit of 42 particles µL-1 and a linear range of 102 to 107 particles µL-1. The constructed aptasensor showed satisfactory reproducibility, stability, and selectivity, confirming the promising application of exosomes in clinical cancer detection.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Exossomos , Estreptavidina , Biotina , Reprodutibilidade dos Testes , Técnicas Biossensoriais/métodos , Limite de Detecção
12.
Talanta ; 265: 124848, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37352782

RESUMO

As a novel class of non-invasive biomarkers, exosome-carried proteins are essential in early detection and precise cancer diagnosis. In the study, we developed an electrochemical biosensor based on MXenes-Au NPs modification to assess the differential expression of EGFR, CEA, and EpCAM proteins of exosomes. This sensor has sensitively detected tumor biomarkers in the exosomes generated by various tumor cells (including A549, MCF-7, PC-3, and HeLa). Building a biosensor that can distinguish minute differences of proteins in various derived-from exosomes is crucial for addressing the issues with early and accurate cancer detection.


Assuntos
Técnicas Biossensoriais , Exossomos , Humanos , Proteínas de Membrana/metabolismo , Exossomos/química , Biomarcadores Tumorais/análise , Células HeLa
13.
Mikrochim Acta ; 190(4): 147, 2023 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-36947252

RESUMO

The detection signal of carbohydrate antigen 125 (CA125) can be quantitatively amplified via the dual metal-organic framework (MOF) sandwich strategy. We propose a versatile method for synthesizing uniform MXene and MIL-101(Fe)-NH2 composites that combine the advantages of both materials to build a base layer with superb performance. MXene exhibits excellent electrical conductivity and high surface area. The mesoporous MIL-101(Fe)-NH2 not only increases the loading capacity of the primary antibody but also possesses the catalytic activity of the metal center (Fe). UiO66 loaded with methylene blue (MB) was fabricated as an electrochemical immunosensor signal tag to enable the detection of CA125. The mixture of MXene and MIL-101(Fe)-NH2 prepared as the substrate was fixed by chitosan rich in amino groups. As the signal amplification sector, UiO66@MB enhanced secondary antibody loading capacity and generated a redox signal enabling the detection of antigenic substances. The proposed electrochemical immunosensor demonstrated high sensitivity with a low limit of detection (LOD) of 0.006 U/mL. Therefore, the dual MOF sandwich-based immunosensor provides a novel method for the early diagnosis of CA125.


Assuntos
Biomarcadores Tumorais , Técnicas Biossensoriais , Técnicas Biossensoriais/métodos , Anticorpos Imobilizados , Imunoensaio/métodos , Anticorpos , Antígeno Ca-125 , Azul de Metileno/química
14.
Food Chem ; 417: 135813, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36913870

RESUMO

A high performance liquid chromatography was established to determine purine content of prepackaged food. Chromatographic separation was performed on Agilent5 TC-C18 column. Ammonium formate (10 mmol/L, pH = 3.385) and methanol (99:1) were used as mobile phase. Purine concentration and peak area showed good linear relationships in the range from 1 to 40 mg/L (guanine, hypoxanthine, adenine) and xanthine exhibited a good linear relationship ranged from 0.1 to 4.0 mg/L. Recoveries of four purines ranged from 93.03% to 107.42%. Purine content in prepackaged food was following: animal derived prepackaged food: 16.13-90.18 mg/100 g; beans and bean products: 66.36-157.11 mg/100 g; fruits and fruit products: 5.64-21.79 mg/100 g; instant rice and flour products: 5.68-30.83 mg/100 g; fungi, algae, fungi and algae products: 32.57-70.59 mg/100 g. This proposed method had good precision and accuracy with a wide linear range for detection of purine. Animal derived prepackaged food was purine-rich food, purine content of plant derived prepackaged food varied greatly.


Assuntos
Purinas , Animais , Cromatografia Líquida de Alta Pressão/métodos , Hidrólise , Purinas/análise , Xantina
15.
Expert Rev Mol Diagn ; 23(4): 325-334, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36970945

RESUMO

OBJECTIVE: The relationship between noncoding RNAs and the prognosis of bladder cancer (BC) is still controversial. The purpose of this study is to evaluate the relationship between noncoding RNAs and prognosis by meta-analysis. METHODS: Comprehensive retrieval of PubMed, Embase, the Cochrane Library, the Web of Science, CNKI, and WanFang databases is related to the correlation between noncoding RNAs and the prognosis of BC. Data were extracted, and the literature quality was evaluated. STATA16.0 served for the meta-analysis. RESULTS: 1. CircRNAs: High circ-ZFR expression led to poor overall survival (OS) of BC. 2. LncRNAs: Low lnc-GAS5 expression predicted poor OS of BC, high lnc-TUG1 expression predicted poor OS of BC. 3. MiRNAs: High miR-21 expression predicted poor OS of BC, high miR-222 expression led to poor OS of BC, high miR-155 expression predicted poor progression-free survival (PFS) of BC, high miR-143 expression caused poor PFS of BC, low miR-214 expression could result in poor recurrence-free survival (RFS) of BC. CONCLUSIONS: High circ-ZFR, lnc-TUG1, miR-222, and miR-21 expressions were correlated with poor OS of BC; high miR-155 and miR-143 expression predicted poor PFS of BC; low lnc-GAS5 expression predicted poor OS of BC; low miR-214 expression predicted poor RFS of BC.


Assuntos
MicroRNAs , RNA Longo não Codificante , Neoplasias da Bexiga Urinária , Humanos , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , MicroRNAs/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismo , Regulação Neoplásica da Expressão Gênica
16.
Biosens Bioelectron ; 228: 115175, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36871422

RESUMO

Circulating cell-free DNA (cfDNA) is a promising biomarker of liquid biopsy, but it still faces some difficulties in achieving sensitive and convenient detection. Herein, an Ω-shaped fiber optic localized surface plasmon resonance (FO-LSPR) biosensor based on hybridization chain reaction (HCR) coupled with gold nanoparticles (AuNPs) was developed, and applied in simple and sensitive detection of cfDNA. Specifically, one-base mismatch was designed in HCR hairpins (H1 and H2) to obtain high reaction efficiency, and AuNPs was introduced onto H1 through poly-adenine to construct HCR coupled with AuNPs strategy. Meanwhile, target cfDNA was designed into two domains: one could trigger HCR to generate dsDNA concatemer carrying numerous AuNPs, and the other could hybridize with capture DNA on the surface of Ω-shaped fiber optic (FO) probes. Thus, the presence of target cfDNA would initiate HCR, and bring the formed dsDNA concatemer and AuNPs to approach the probe surface, resulting in dramatically amplified LSPR signal. Besides, HCR required simple isothermal and enzyme-free condition, and Ω-shaped FO probe with high refractive index sensitivity just needed to be immersed into HCR solution directly for signal monitoring. Benefiting from the synergetic amplification of mismatched HCR and AuNPs, the proposed biosensor exhibited high sensitivity with a limit of detection of 14.0 pM, and therefore could provide a potential strategy for biomedical analysis and disease diagnosis.


Assuntos
Técnicas Biossensoriais , Ácidos Nucleicos Livres , Nanopartículas Metálicas , Ouro , Hibridização de Ácido Nucleico/métodos , DNA/genética , DNA/análise , Limite de Detecção
17.
Biochim Biophys Acta Gen Subj ; 1867(1): 130251, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36244576

RESUMO

CdSe/ZnS Quantum dots (QDs) are possibly released to surface water due to their extensive application. Based on their high reactivity, even small amounts of toxicant QDs will disturb water microbes and pose a risk to aquatic ecology. Here, we evaluated CdSe/ZnS QDs toxicity to Tetrahymena thermophila (T. thermophila), a model organism of the aquatic environment, and performed metabolomics experiments. Before the omics experiment was conducted, QDs were found to induce inhibition of cell proliferation, and reactive oxygen species (ROS) production along with Propidium iodide labeled cell membrane damage indicated oxidative stress stimulation. In addition, mitochondrial ultrastructure alteration of T. thermophila was also confirmed by Transmission Electron Microscope results after 48 h of exposure to QDs. Further results of metabolomics detection showed that 0.1 µg/mL QDs could disturb cell physiological and metabolic metabolism characterized by 18 significant metabolite changes, of which twelve metabolites improved and three decreased significantly compared to the control. Kyoto Encyclopedia of Genes and Genomes analysis showed that these metabolites were involved in the ATP-binding cassette transporter and purine metabolism pathways, both of which respond to ROS-induced cell membrane damage. In addition, purine metabolism weakness might also reflect mitochondrial dysfunction associated with energy metabolism and transport abnormalities. This research provides deep insight into the potential risks of quantum dots in aquatic ecosystems.


Assuntos
Compostos de Cádmio , Pontos Quânticos , Compostos de Selênio , Tetrahymena thermophila , Pontos Quânticos/toxicidade , Compostos de Cádmio/toxicidade , Compostos de Cádmio/química , Compostos de Selênio/farmacologia , Tetrahymena thermophila/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Ecossistema , Estresse Oxidativo , Água , Purinas , Lipídeos
18.
Micromachines (Basel) ; 15(1)2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38276840

RESUMO

SAW devices with a multi-layered piezoelectric substrate have excellent performance due to advantages such as a high quality factor, Q, low loss insertion, large bandwidth, etc. Prior to manufacturing, a comprehensive analysis and proper design are essential to evaluating the device's key performance indicators, including the Bode Q value, bandwidth, and transverse mode suppression. This study explored the performance of SAW resonators employing a 42°Y-X LiTaO3 (LT) thin-plate-based multi-layered piezoelectric substrate. The thicknesses for each layer of the 42°Y-X LT/SiO2/poly-Si/Si substrate were optimized according to the index of phase velocity, Bode Q value, and bandwidth. The effect of the device structure parameters on the dispersion curve and slowness curve was studied, and a flat slowness curve was found to be favorable for transverse mode suppression. In addition, the design of the dummy configuration was also optimized for the suppression of spurious waves. Based on the optimized design, a one-port resonator on the 42°Y-X LT/SiO2/poly-Si/Si substrate was fabricated. The simulation results and measurements are presented and compared, which provides guidelines for the design of new types of SAW devices configured with complex structures.

19.
Artigo em Inglês | MEDLINE | ID: mdl-36525187

RESUMO

People pose a serious risk by plants contaminated with lead in soil. However, the strength of lead enrichment capacity in root, stem, and leaf of the plant is still controversial. Therefore, a meta-analysis was conducted to investigate the ability of lead enrichment of root, stem, and leaf and the main influencing factors for lead absorption. The results of this study indicated that all parts of plant can significantly accumulate lead. Concentrations of lead followed an order of root > stem > leaf. Alkaline soil was conducive to the absorption of lead. When the lead concentration in the soil was higher than 20 mg/kg, the lead absorption in root was more. Lead is absorbed most in trees and least in Gramineae. It is argued that this study is beneficial to select plants suitable for absorption of lead from polluted soil. This study also can help to clarify the influencing factors for lead enrichment in different parts of the plant.

20.
Bioelectrochemistry ; 148: 108230, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36029760

RESUMO

An electrochemical immunosensor based on the modification of nanocomposite was constructed to detect the lung cancer marker Cytokeratin 19 fragment antigen 21-1 (CYFRA21-1). Ordered mesoporous carbon CMK-3 was selected to mix with carboxylated multi-walled carbon nanotubes (CMWCNTs), and their combination could enhance electron transfer efficiency and amplify the electrochemical signal. Furthermore, aurum nanoparticles (AuNPs) were further mixed with the hybrid carbon nanomaterials, which bind antibodies via Au-S bonds and provide numerous of binding sites for antibodies. Finally, CYFRA21-1 could be detected by specific immune response between antigen and antibody by improving the immunosensor sensitivity. The characterization of scanning electron microscopy (SEM) showed that AuNPs were embedded on the surface and interstices of CMK-3@CMWCNTs. The curves of cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) showed that the immunsensor was successfully constructed. The constructed immunosensor had a linear range of 0.5 pg/mL to 105 pg/mL for the detection of CYFRA21-1 in serum, and the correlation coefficient (r) was 0.998, with a detection limit of 0.2 pg/mL. Thus, this method is selective and sensitive for getting the accurate and reliable detection results and provides a new method for the CYFRA21-1 ultrasensitive detection in serum.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Nanocompostos , Nanotubos de Carbono , Antígenos de Neoplasias , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Ouro/química , Imunoensaio , Queratina-19 , Limite de Detecção , Nanopartículas Metálicas/química , Nanocompostos/química , Nanotubos de Carbono/química
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