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1.
Mikrochim Acta ; 190(6): 214, 2023 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-37171612

RESUMO

A new ultrasensitive sandwich-type electrochemical immunosensor has been successfully constructed to quantitatively detect carcinoembryonic antigen (CEA) using blackberry-like mesoporous bismuth-based nanospheres NaBiOF (NBOF NSs) inlaid with Pt nanodots (NDs) (BiPt NSs) as the antibody capture and signal-amplifying probe. The growth of Pt NDs inside the holes of NBOF NSs formed the nanozyme inlay outside NBOF NSs, greatly increasing the specific surface area and exposure of the catalytic active sites by minimizing the particle size of the Pt to nanodot scale. Such a blackberry-shaped heterojunction structure of BiPt NSs was well-suited to antibody capture and improved the catalytic performance of BiPt NSs in reducing H2O2, amplifying the signal, and yielding highly sensitive detection of CEA. The use of Au nanoparticle-modified multi-walled carbon nanotubes (Au@MWCNTs) as the electrode substrates significantly enhanced the electron transfer behavior over the electrode surface, further increasing the conductivity and sensitivity of the immunosensor. Remarkably, good compatibility with human body fluid was achieved using the newly developed BiPt-based immunosensor resulting from the favorable biocompatibility and stability of both BiPt NSs and Au@MWCNTs. Benefiting from the double signal amplification strategy and the high biocompatibility, the immunosensor responded linearly to CEA in a wide range from 50 fg/mL to 100 ng/ml with an extremely low detection limit of 3.52 fg/mL (S/N = 3). The excellent detection properties of this new immunosensor were evidenced by the satisfactory selectivity, reproducibility, and stability obtained, as well as the reliable and precise determination  of CEA in actual human blood samples. This work provides a new strategy for the early clinical diagnosis of cancer. Novel blackberry-like mesoporous NaBiOF nanospheres with Pt nanodot inlay were successfully usedto construct a sandwich-type electrochemical immunosensor for the ultra-sensitive detection ofcarcinoembryonic antigen in human blood plasma based on a remarkable signal amplification strategy.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Nanotubos de Carbono , Humanos , Antígeno Carcinoembrionário , Ouro/química , Técnicas Biossensoriais/métodos , Nanotubos de Carbono/química , Peróxido de Hidrogênio/química , Reprodutibilidade dos Testes , Nanopartículas Metálicas/química , Anticorpos Imobilizados/química , Técnicas Eletroquímicas/métodos , Imunoensaio/métodos , Anticorpos
2.
Sensors (Basel) ; 23(17)2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37687984

RESUMO

In the pursuit of automating the entire underground drilling process in coal mines, the automatic rod feeding technology of drilling robots plays a crucial role. However, the current lack of positional accuracy in automatic rod feeding leads to frequent accidents. To address this issue, this paper presents an algorithm for compensating positioning errors in automatic rod feeding. The algorithm is based on a theoretical mathematical model and manual teaching methods. To enhance the positioning accuracy, we first calibrate the pull rope sensor to correct its measurement precision. Subsequently, we establish a theoretical mathematical model for rod feeding positions by employing spatial coordinate system transformations. We determine the target rod feeding position using a manual teaching-based approach. Furthermore, we analyze the relationship between the theoretical rod delivery position and the target rod delivery position and propose an anisotropic spatial difference compensation technique that considers both distance and direction. Finally, we validate the feasibility of our proposed algorithm through automatic rod feeding tests conducted on a coal mine underground drilling robot. The results demonstrate that our algorithm significantly improves the accuracy of rod feeding positions for coal mine underground drilling robots.

3.
Small ; 18(9): e2104550, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34910856

RESUMO

Excess generation of reactive oxygen species (ROS) based on sensitizers under ultrasound (US) excitation can cause the death of tumor cells via oxidative damage, but sonosensitizers are largely unexplored. Herein, oxygen-deficient black BiOCl (B-BiOCl) nanoplates (NPs) are reported, with post-treatment on conventional BiOCl by simple UV excitation, showing stronger singlet oxygen (1 O2 ) generation than commercial TiO2 nanoparticles and their derivatives under US irradiation. Moreover, L-buthionine-sulfoximine (BSO), a GSH biosynthesis inhibitor, is incorporated into B-BiOCl NPs. The authors find that BSO can be released owing to the degradation of B-BiOCl NPs in the presence of acid and GSH, which are overexpressed in tumors. The results show that BSO/B-BiOCl-PEG NPs have a multifunctional synergistic effect on improving ROS production. In particular, BiOCl has remarkable near-infrared light absorption after UV treatment and is good for photoacoustic imaging that can guide subsequent sonodynamic therapy. This work shows that just with a simple oxygen deficiency treatment, strong 1 O2 generation can be provided to a conventional material under US irradiation and, interestingly, this effect can be amplified by using a small inhibitor BSO, and this is clearly demonstrated in cell and mice experiments.


Assuntos
Glutationa , Oxigênio Singlete , Animais , Glutationa/metabolismo , Hipóxia , Metionina/análogos & derivados , Camundongos , Oxigênio , Espécies Reativas de Oxigênio/metabolismo
4.
Front Immunol ; 15: 1267963, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38464509

RESUMO

Background: Coronary artery disease (CAD) and type 2 diabetes mellitus (T2DM) are closely related. The function of immunocytes in the pathogenesis of CAD and T2DM has not been extensively studied. The quantitative bioinformatics analysis of the public RNA sequencing database was applied to study the key genes that mediate both CAD and T2DM. The biological characteristics of associated key genes and mechanism of CD8+ T and NK cells in CAD and T2DM are our research focus. Methods: With expression profiles of GSE66360 and GSE78721 from the Gene Expression Omnibus (GEO) database, we identified core modules associated with gene co-expression relationships and up-regulated genes in CAD and T2DM using Weighted Gene Co-expression Network Analysis (WGCNA) and the 'limma' software package. The enriched pathways of the candidate hub genes were then explored using GO, KEGG and GSEA in conjunction with the immune gene set (from the MSigDB database). A diagnostic model was constructed using logistic regression analysis composed of candidate hub genes in CAD and T2DM. Univariate Cox regression analysis revealed hazard ratios (HRs), 95% confidence intervals (CIs), and p-values for candidate hub genes in diagnostic model, while CIBERSORT and immune infiltration were used to assess the immune microenvironment. Finally, monocytes from peripheral blood samples and their immune cell ratios were analyzed by flow cytometry to validate our findings. Results: Sixteen candidate hub genes were identified as being correlated with immune infiltration. Univariate Cox regression analysis revealed that NPEPPS and ABHD17A were highly correlated with the diagnosis of CAD and T2DM. The results indicate that CD8+ T cells (p = 0.04) and NKbright cells (p = 3.7e-3) are significantly higher in healthy controls than in individuals with CAD or CAD combined with T2DM. The bioinformatics results on immune infiltration were well validated by flow cytometry. Conclusions: A series of bioinformatics studies have shown ABHD17A and NPEPPS as key genes for the co-occurrence of CAD and T2DM. Our study highlights the important effect of CD8+ T and NK cells in the pathogenesis of both diseases, indicating that they may serve as viable targets for diagnosis and therapeutic intervention.


Assuntos
Doença da Artéria Coronariana , Diabetes Mellitus Tipo 2 , Humanos , Doença da Artéria Coronariana/genética , Diabetes Mellitus Tipo 2/genética , Regulação para Cima , Linfócitos T CD8-Positivos , Células Matadoras Naturais , Bases de Dados de Ácidos Nucleicos
5.
ACS Nano ; 17(4): 4009-4022, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36757738

RESUMO

Enhanced imaging techniques using contrast agents enable high-resolution structural imaging to reveal space-occupying lesions but rarely provide detailed molecular information. To this end, we report a structural and molecular fusion magnetic resonance imaging (MRI) nanoprobe for differential diagnosis between benign and malignant tumors. This fusion nanoprobe, termed FFT NPs, follows a working mechanism involving a T1-/T2-weighted magnetic resonance tuning effect (MRET) between a magnetic Fe3O4 core and a paramagnetic Fe-tannic acid (Fe-TA) shell. The FFT NPs with an "always-on" inert T2 signal provide structural MRI (sMRI) contrast of tumors while affording an activated T1 signal in the presence of ATP, which is overproduced during the rapid growth of malignant tumors to enable molecular MRI (mMRI) of tumor lesions. We propose the use of the ratiometric mMRI:sMRI intensity to assist in the differential diagnosis of malignant 4T1 tumors from benign L929 fibroblast tumors. Furthermore, the dissociated FFT NPs were found to be able to catalyze H2O2 conversion in 4T1 tumors to generate excess reactive oxygen species (ROS) for chemodynamic therapy. The described fusion nanoprobe strategy enables the differential diagnosis of tumors from a combined spatial and molecular perspective with one-stop MRI imaging with potential applications in precision intervention.


Assuntos
Peróxido de Hidrogênio , Neoplasias , Humanos , Diagnóstico Diferencial , Seguimentos , Imageamento por Ressonância Magnética/métodos , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Meios de Contraste/química
6.
Colloids Surf B Biointerfaces ; 220: 112924, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36308884

RESUMO

A new sandwich-type electrochemical immunosensor for the sensitive detection of carcinoembryonic antigen (CEA) was originally developed using a unique bismuth (Bi)-gold (Au) nano-electrocatalyst triggering efficient capture of tumor marker, where the nano-electrocatalyst was obtained by implanting Au nanoparticles (Au NPs) inside the mesoporous NBiOF nanospheres (Au@NBOF NSs) for the purpose to marker secondary antibody (Ab2) and amplify the response signal through electrochemically catalyzing the reduction of hydrogen peroxide. The synergistic interaction between NBOF NSs and Au NPs endowed the as-received Au@NBOF nano-electrocatalyst with large electrocatalytic active surface area and powerful signal amplification function as upper sandwich layer to conjugate Ab2. The multi-walled carbon nanotubes sparkled with Au nanostars served as the lower sandwich layer to capture the primary antibody (Ab1), which enhanced the interfacial electron transport and the load capacity of Ab1 as a result of increasing the sensing response of the designed immunosensor based on the sandwich-type Ab1-CEA-Ab2 interaction. Such immunosensor proposed on the above double signal amplification strategy efficiently detected the target CEA in a wide concentration range from 100 fg mL-1 to 200 ng mL-1. The detection limit was as low as 9.57 fg mL-1 with excellent specificity and reproducibility. The satisfactory results in analyzing human serum samples indicate the potential application of this new immunosensor in early clinical diagnosis of cancer and the evaluation of treatment efficiency.


Assuntos
Técnicas Biossensoriais , Grafite , Nanopartículas Metálicas , Nanotubos de Carbono , Humanos , Ouro , Antígeno Carcinoembrionário , Bismuto , Técnicas Eletroquímicas/métodos , Biomarcadores Tumorais , Reprodutibilidade dos Testes , Imunoensaio/métodos , Limite de Detecção , Anticorpos Imobilizados
7.
Bioact Mater ; 6(2): 386-403, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32954056

RESUMO

To fabricate a highly biocompatible nanoplatform enabling synergistic therapy and real-time imaging, novel Au@Bi2S3 core shell nanobones (NBs) (Au@Bi2S3 NBs) with Au nanorods as cores were synthesized. The combination of Au nanorods with Bi2S3 film made the Au@Bi2S3 NBs exhibit ultrahigh photothermal (PT) conversion efficiency, remarkable photoacoustic (PA) imaging and high computed tomography (CT) performance; these Au@Bi2S3 NBs thus are a promising nanotheranostic agent for PT/PA/CT imaging. Subsequently, poly(N-vinylpyrrolidone)-modified Au@Bi2S3 NBs (Au@Bi2S3-PVP NBs) were successfully loaded with the anticancer drug doxorubicin (DOX), and a satisfactory pH sensitive release profile was achieved, thus revealing the great potential of Au@Bi2S3-PVP NBs in chemotherapy as a drug carrier to deliver DOX into cancer cells. Both in vitro and in vivo investigations demonstrated that the Au@Bi2S3-PVP NBs possessed multiple desired features for cancer therapy, including extremely low toxicity, good biocompatibility, high drug loading ability, precise tumor targeting and effective accumulation. Highly efficient ablation of the human liver cancer cell HepG2 was achieved through Au@Bi2S3-PVP NB-mediated photothermal therapy (PTT). As both a contrast enhancement probe and therapeutic agent, Au@Bi2S3-PVP NBs provided outstanding NIR-triggered multi-modal PT/PA/CT imaging-guided PTT and effectively inhibited the growth of HepG2 liver cancer cells via synergistic chemo/PT therapy.

8.
RSC Adv ; 10(13): 7740-7750, 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-35492191

RESUMO

Reactive oxygen species (ROS) are by-products of aerobic metabolism and can also act as signaling molecules to participate in multiple regulation of biological and physiological processes. The occurrence, growth and metastasis of tumors, and even the apoptosis, necrosis and autophagy of tumor cells are all closely related to ROS. However, ROS levels in the body are usually maintained at a stable status. ROS produced by oxidative stress can cause damage to cell lipids, protein and DNA. In recent years, ROS have achieved satisfactory results on the treatment of tumors. Therefore, this review summarizes some research results of tumor treatments from the perspective of ROS in recent years, and analyzes how to achieve the mechanism of inhibition and treatment of tumors by ROS or how to affect the tumor microenvironment by influencing ROS. At the same time, the detection methods of ROS, problems encountered in the research process and solutions are also summarized. The purpose of this review is to provide a clearer understanding of the ROS role in tumor treatment, so that researchers might have more inspiration and thoughts for cancer prevention and treatment in the next stage.

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