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1.
Mikrochim Acta ; 190(1): 44, 2023 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-36602637

RESUMEN

Integrated polyurethane (PU)-based foams modified with PEGylated graphene oxide and folic acid (PU@GO-PEG-FA) were developed with the goal of capturing and detecting tumor cells with precision. The detection of the modified PU@GO-PEG surface through FA against folate receptor-overexpressed tumor cells is the basis for tumor cell capture. Molecular dynamics (MD) simulations were applied to study the strength of FA interactions with the folate receptor. Based on the obtained results, the folate receptor has intense interactions with FA, which leads to the reduction in the FA interactions with PEG, and so decreases the fluorescence intensity of the biosensor. The synergistic interactions offer the FA-modified foams a high efficiency for capturing the tumor cell. Using a turn-off fluorescence technique based on the complicated interaction of FA-folate receptor generated by target recognition, the enhanced capture tumor cells could be directly read out at excitation-emission wavelengths of 380-450 nm. The working range is between 1×10 2 to 2×10 4 cells mL -1 with a detection limit of 25 cells mL -1 and good reproducibility with relative standard deviation of 2.35%. Overall, findings demonstrate that the fluorescence-based biosensor has a significant advantage for early tumor cell diagnosis.


Asunto(s)
Ácido Fólico , Poliuretanos , Simulación de Dinámica Molecular , Reproducibilidad de los Resultados
2.
BMC Urol ; 22(1): 133, 2022 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-36038861

RESUMEN

BACKGROUND: The significance of total and specific subpopulations of tumor-infiltrating lymphocytes (TILs) in cancer is now well-documented. In the present study, we investigated the relevance of CD3+, CD8 +, CD45RO +, and FOXP3 + TILs to the prognosis and survival of patients with bladder cancer and the disease's clinical-pathological parameters. METHODS: Infiltration of each subset was immunohistochemically evaluated in both stromal and intratumoral regions of tumor tissues from 85 patients with urothelial cell carcinoma of the bladder, with known survival. RESULTS: Our results indicated that intratumoral CD45RO+ lymphocytes were significantly higher in high-grade tumors than in low-grade ones (P = 0.028). The frequencies of intratumoral CD3+ (P = 0.002), CD8 + (P = 0.008), intratumoral (P = 0.002), and stromal (P = 0.017) CD45RO+ lymphocytes were also higher in patients with muscular invasion than those without invasion. The frequencies of intratumoral CD3+ (P = 0.043), CD8+ (P = 0.003), CD45RO+ (P = 0.023), and total CD45RO+ (P = 0.015), showed variation in patients with different T-stage, as well; mostly increased in T2 versus Ta and T1. Comparing patients in different stages revealed an increase in the frequencies of total CD3+ (P = 0.011), intratumoral CD3+ (P = 0.006), total CD8+ (P = 0.012), intratumoral CD8+ (P = 0.009) and stromal CD8+ (P = 0.034), as well as total and stromal CD45RO+ lymphocytes (P = 0.01 and P = 0.034, respectively) in stage II comparing to stage I, while the frequencies of stromal CD3+ (P = 0.077) and CD8+ (P = 0.053) cells tended to be decreased in stage III compared to stage II. CONCLUSIONS: We collectively observed that the frequency of immune cells, especially CD45RO+, CD3+, and CD8+ lymphocytes, were significantly higher in early-progressed tumors. This observation could be explained by continuous and prolonged stimulation of immune cells with tumor antigens during tumor progression or an increase in the recruiting factors, especially in the early stages, to eliminate tumor cells. However, with tumor progression to the late stages, the inhibitory microenvironment provided by tumor cells suppresses or changes the functionality of the effector and memory immune cells to help tumor growth. However, more functional studies with larger sample sizes are needed to reveal the real status of the immune system in patients with bladder cancer.


Asunto(s)
Carcinoma de Células Transicionales , Neoplasias de la Vejiga Urinaria , Biomarcadores , Linfocitos T CD8-positivos/patología , Carcinoma de Células Transicionales/patología , Humanos , Antígenos Comunes de Leucocito , Linfocitos Infiltrantes de Tumor/patología , Pronóstico , Microambiente Tumoral , Neoplasias de la Vejiga Urinaria/patología
3.
Mikrochim Acta ; 186(12): 773, 2019 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-31720840

RESUMEN

This review, with 201 references, describes the recent advancement in the application of carbonaceous nanomaterials as highly conductive platforms in electrochemical biosensing. The electrochemical biosensing is described in introduction by classifying biosensors into catalytic-based and affinity-based biosensors and statistically demonstrates the most recent published works in each category. The introduction is followed by sections on electrochemical biosensors configurations and common carbonaceous nanomaterials applied in electrochemical biosensing, including graphene and its derivatives, carbon nanotubes, mesoporous carbon, carbon nanofibers and carbon nanospheres. In the following sections, carbonaceous catalytic-based and affinity-based biosensors are discussed in detail. In the category of catalytic-based biosensors, a comparison between enzymatic biosensors and non-enzymatic electrochemical sensors is carried out. Regarding the affinity-based biosensors, scholarly articles related to biological elements such as antibodies, deoxyribonucleic acids (DNAs) and aptamers are discussed in separate sections. The last section discusses recent advancements in carbonaceous screen-printed electrodes as a growing field in electrochemical biosensing. Tables are presented that give an overview on the diversity of analytes, type of materials and the sensors performance. Ultimately, general considerations, challenges and future perspectives in this field of science are discussed. Recent findings suggest that interests towards 2D nanostructured electrodes based on graphene and its derivatives are still growing in the field of electrochemical biosensing. That is because of their exceptional electrical conductivity, active surface area and more convenient production methods compared to carbon nanotubes. Graphical abstract Schematic representation of carbonaceous nanomaterials used in electrochemical biosensing. The content is classified into non-enzymatic sensors and affinity/ catalytic biosensors. Recent publications are tabulated and compared, considering materials, target, limit of detection and linear range of detection.


Asunto(s)
Anticuerpos/análisis , Aptámeros de Nucleótidos/análisis , Técnicas Biosensibles , ADN/análisis , Técnicas Electroquímicas , Nanotubos de Carbono/química , Tamaño de la Partícula , Propiedades de Superficie
4.
Anal Chim Acta ; 1252: 341017, 2023 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-36935143

RESUMEN

Developing smartphone technology for point-of-care diagnosis is one of the current favorable trends in the field of biosensors. In fact, using smartphones can provide better accessibility and facility for rapid diagnosis of diseases. On the other hand, the detection of circulating tumor cells (CTCs) is one of the recent methods for the early diagnosis of cancer. Here, a new smartphone-assisted lab-in-a-tube device is introduced for the detection of Mucin 1 (MUC1) overexpressed tumor-derived cell lines using gold nanoclusters (GNCs)-based aptasensor. Accordingly, commercial polyurethane (PU) foam was first coated with graphene oxide (GO) to increase its surface area (8.45-fold), and improve its wettability. The surface of the resulting three-dimensional PU-GO (3DPU-GO) platform was then modified by MUC1 aptamer-GNCs to provide the required sensitivity and specificity through a turn "on/off" detection system. The proposed biosensor was first optimized with a spectrophotometer method. Afterward, findings were evaluated based on the red color intensity of the lab-in-a-tube system; and indicated the high ability of the biosensor for detection of MUC1-overexpressed tumor cell lines in the range of 250-20,000 cells mL-1 with a limit of detection of 221 cells mL-1. In addition, the developed biosensor showed a decent selectivity against positive-control cell lines (MCF-7, and HT-29) in comparison to negative-control cell lines (HEK293, and L929). Notably, the results represented good accordance with reference methods including spectroscopy devices. Ultimately, the results of this work bring a new perspective to the field of point-of-care detection and can be considered in future biosensors.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Nanopartículas del Metal , Humanos , Mucina-1/metabolismo , Teléfono Inteligente , Oro/química , Células HEK293 , Técnicas Biosensibles/métodos , Aptámeros de Nucleótidos/química , Límite de Detección , Nanopartículas del Metal/química
5.
J Mater Chem B ; 10(7): 990-1004, 2022 02 16.
Artículo en Inglés | MEDLINE | ID: mdl-35107117

RESUMEN

Blood analysis is an established approach to monitor various diseases, ranging from heart defects and diabetes to cancer. Among various tumor markers in the blood, circulating tumor cells (CTCs) have received increasing attention due to the fact that they originate directly from the tumors. Capturing and detecting CTCs represents a promising approach in cancer diagnostics and clinical management of cancers. CTCs in blood progress to self-seeding a tumour or initiating a new lesion mass. Cytosensors are biosensors intended to identify CTCs in a blood sample of cancer patients and provide information about the cancer status. Herein, we firstly discuss different detection methods of state-of-the-art optical cytosensors, including colorimetry, fluorescence, surface plasmon resonance, photoelectrochemistry and electrochemiluminescence. Then we review the significant advances made in implementing biorecognition elements and nanomaterials for the detection of cancer cells. Despite great progress in optical cytosensors, and their integration with smartphones, they have still only been explored to prototype stages. Much more effort is needed to fulfil their potential in modern cancer diagnostics and in monitoring the state of disease for cancer patients.


Asunto(s)
Técnicas Biosensibles , Nanoestructuras , Células Neoplásicas Circulantes , Biomarcadores de Tumor/análisis , Técnicas Biosensibles/métodos , Recuento de Células , Humanos , Células Neoplásicas Circulantes/patología
6.
Biomater Adv ; 137: 212809, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35929249

RESUMEN

Macroporous scaffolds with bioactivity and magnetic properties can be a good candidate for bone regeneration and hyperthermia. In addition, modifying the surface of the scaffolds with biocompatible materials can increase their potential for in vivo applications. Here, we developed a multifunctional nanocomposite Mg2SiO4-CuFe2O4 scaffold for bone regeneration and hyperthermia. The surface of scaffold was coated with various concentrations of poly-3-hydroxybutyrate (P3HB, 1-5% (w/v)). It was observed that 3% (w/v) of P3HB provided a favorable combination of porosity (79 ± 2.1%) and compressive strength (3.2 ± 0.11 MPa). The hyperthermia potential of samples was assessed in the presence of various magnetic fields in vitro. The coated scaffolds showed a lower degradation rate than the un-coated one up to 35 days of soaking in simulated biological medium. Due to the porous and specific morphology of P3HB, it was found that in vitro bioactivity and cell attachment were increased on the scaffold. Moreover, it was observed that the P3HB coating improved the cell viability, alkaline phosphatase activity, and mineralization of the scaffold. Finally, we studied the bone formation ability of the scaffolds in vivo, and implanted the developed scaffold in the rat's femur for 8 weeks. Micro-computed tomography results including bone volume fraction and trabecular thickness exhibited an improvement in the bone regeneration of the coated scaffold compared to the control. The overall results of this study introduce a highly macroporous scaffold with multifunctional performance, noticeable ability in bone regeneration, and hyperthermia properties for osteosarcoma.


Asunto(s)
Hipertermia Inducida , Animales , Regeneración Ósea , Huesos , Fenómenos Magnéticos , Ratas , Microtomografía por Rayos X
7.
Int J Biol Macromol ; 202: 241-255, 2022 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-35041881

RESUMEN

A cancer nanotheranostic system was fabricated based on mesoporous silica@chitosan@gold (MCM@CS@Au) nanosystem targeted by aptamer toward the MUC-1 positive tumor cells. Subsequently, curcumin as an efficient herbal anticancer drug was first encapsulated into chitosan-triphosphate nanoparticles and then the resulted nanoparticle was loaded into the nanosystem (MCM@CS@Au-Apt). The nanosystem successful fabrication was approved at each synthesis step through FTIR, XRD, BET, DLS, FE-SEM, HRTEM, and fluorescence spectroscopy. Besides, the interaction between aptamer and curcumin was evaluated using full atomistic molecular dynamics simulations. The mechanism of curcumin release was likewise investigated through different kinetic models. Afterwards, the potential of the designed nanosystem in targeted imaging, and drug delivery was evaluated using fluorescence microscopy and flow cytometry. It was found that the energy transfer between the base pairs in the hairpin of double strands of DNA aptamer acts as a quencher for MCM@CS@Au fluorescence culminating in an "on/off" optical biosensor. On the other hand, the presence of pH-sensitive chitosan nanoparticles creates smart nanosystem to deliver more curcumin into the desired cells. Indeed, when the aptamer specifically binds to the MUC-1 receptor, its double strands separate under the low pH condition, leading to the drug release and the recovery of the fluorescence ("On" state). Based on the toxicity results, this nanosystem had more toxicity toward the MUC-1-positive tumor cells than MUC-1-negative cells, representing its selective targeting. Therefore, this nanosystem could be introduced as a smart anticancer nanotheranostic system for tracing particular biomarkers (MUC-1), non-invasive fluorescence imaging, and targeted curcumin delivery.


Asunto(s)
Técnicas Biosensibles , Quitosano , Nanopartículas del Metal , Nanopartículas , Neoplasias , Quitosano/química , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos , Oro/química , Humanos , Concentración de Iones de Hidrógeno , Nanopartículas del Metal/química , Nanopartículas/química , Neoplasias/tratamiento farmacológico , Medicina de Precisión , Dióxido de Silicio/química
8.
Adv Sci (Weinh) ; 9(33): e2204246, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36253095

RESUMEN

The last pandemic exposed critical gaps in monitoring and mitigating the spread of viral respiratory infections at the point-of-need. A cost-effective multiplexed fluidic device (NFluidEX), as a home-test kit analogous to a glucometer, that uses saliva and blood for parallel quantitative detection of viral infection and body's immune response in an automated manner within 11 min is proposed. The technology integrates a versatile biomimetic receptor based on molecularly imprinted polymers in a core-shell structure with nano gold electrodes, a multiplexed fluidic-impedimetric readout, built-in saliva collection/preparation, and smartphone-enabled data acquisition and interpretation. NFluidEX is validated with Influenza A H1N1 and SARS-CoV-2 (original strain and variants of concern), and achieves low detection limit in saliva and blood for the viral proteins and the anti-receptor binding domain (RBD) Immunoglobulin G (IgG) and Immunoglobulin M (IgM), respectively. It is demonstrated that nanoprotrusions of gold electrodes are essential for the fine templating of antibodies and spike proteins during molecular imprinting, and differentiation of IgG and IgM in whole blood. In the clinical setting, NFluidEX achieves 100% sensitivity and 100% specificity by testing 44 COVID-positive and 25 COVID-negative saliva and blood samples on par with the real-time quantitative polymerase chain reaction (p < 0.001, 95% confidence) and the enzyme-linked immunosorbent assay.


Asunto(s)
COVID-19 , Subtipo H1N1 del Virus de la Influenza A , Humanos , SARS-CoV-2 , Saliva/química , Anticuerpos Antivirales , Inmunoglobulina G , Inmunoglobulina M , Inmunidad
9.
ACS Sens ; 6(3): 797-807, 2021 03 26.
Artículo en Inglés | MEDLINE | ID: mdl-33464874

RESUMEN

Here, we report on an electrochemical biosensor based on core-shell structure of gold nano/micro-islands (NMIs) and electropolymerized imprinted ortho-phenylenediamine (o-PD) for detection of heart-fatty acid binding protein (H-FABP). The shape and distribution of NMIs (the core) were tuned by controlled electrodeposition of gold on a thin layer of electrochemically reduced graphene oxide (ERGO). NMIs feature a large active surface area to achieve a low detection limit (2.29 fg mL-1, a sensitivity of 1.34 × 1013 µA mM-1) and a wide linear range of detection (1 fg mL-1 to 100 ng mL-1) in PBS. Facile template H-FABP removal from the layer (the shell) in less than 1 min, high specificity against interference from myoglobin and troponin T, great stability at ambient temperature, and rapidity in detection of H-FABP (approximately 30 s) are other advantages of this biomimetic biosensor. The electrochemical measurements in human serum, human plasma, and bovine serum showed acceptable recovery (between 91.1 ± 1.7 and 112.9 ± 2.1%) in comparison with the ELISA method. Moreover, the performance of the biosensor in clinical serum showed lower detection time and limit of detection against lateral flow assay (LFA) rapid test kits, as a reference method. Ultimately, the proposed biosensor based on the core-shell structure of gold NMIs and MIP opens interesting avenues in the detection of proteins with low cost, high sensitivity and significantstability for clinical applications.


Asunto(s)
Técnicas Biosensibles , Impresión Molecular , Animales , Bovinos , Oro , Humanos , Islas , Polímeros Impresos Molecularmente
10.
ACS Appl Mater Interfaces ; 12(20): 23298-23310, 2020 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-32302093

RESUMEN

Hierarchical 3D gold nano-/microislands (NMIs) are favorably structured for direct and probe-free capture of bacteria in optical and electrochemical sensors. Moreover, their unique plasmonic properties make them a suitable candidate for plasmonic-assisted electrochemical sensors, yet the charge transfer needs to be improved. In the present study, we propose a novel plasmonic-assisted electrochemical impedimetric detection platform based on hybrid structures of 3D gold NMIs and graphene (Gr) nanosheets for probe-free capture and label-free detection of bacteria. The inclusion of Gr nanosheets significantly improves the charge transfer, addressing the central issue of using 3D gold NMIs. Notably, the 3D gold NMIs/Gr detection platform successfully distinguishes between various types of bacteria including Escherichia coli (E. coli) K12, Pseudomonas putida (P. putida), and Staphylococcus epidermidis (S. epidermidis) when electrochemical impedance spectroscopy is applied under visible light. We show that distinguishable and label-free impedimetric detection is due to dissimilar electron charge transfer caused by various sizes, morphologies, and compositions of the cells. In addition, the finite-difference time-domain (FDTD) simulation of the electric field indicates the intensity of charge distribution at the edge of the NMI structures. Furthermore, the wettability studies demonstrated that contact angle is a characteristic feature of each type of captured bacteria on the 3D gold NMIs, which strongly depends on the shape, morphology, and size of the cells. Ultimately, exposing the platform to various dilutions of the three bacteria strains revealed the ability to detect dilutions as low as ∼20 CFU/mL in a wide linear range of detection of 2 × 101-105, 2 × 101-104, and 1 × 102-1 × 105 CFU/mL for E. coli, P. putida, and S. epidermidis, respectively. The proposed hybrid structure of 3D gold NMIs and Gr, combined by novel plasmonic and conventional impedance spectroscopy techniques, opens interesting avenues in ultrasensitive label-free detection of bacteria with low cost and high stability.


Asunto(s)
Bacterias/aislamiento & purificación , Carga Bacteriana/métodos , Oro/química , Grafito/química , Dispositivos Laboratorio en un Chip , Nanoestructuras/química , Espectroscopía Dieléctrica , Escherichia coli K12/aislamiento & purificación , Técnicas Analíticas Microfluídicas/instrumentación , Técnicas Analíticas Microfluídicas/métodos , Pseudomonas putida/aislamiento & purificación , Staphylococcus epidermidis/aislamiento & purificación , Orina/microbiología
11.
Int Med Case Rep J ; 12: 189-192, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31303798

RESUMEN

Primary renal squamous cell carcinoma (SCC) is a very rare upper urinary tract neoplasm. Renal SCC has a poor prognosis because it usually presents in advanced stages. We report a 64-year-old woman with a right paravertebral mass; after right radical nephroureterectomy and salpingo-oophorectomy, pathologic examination revealed primary SCC.

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