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1.
Ecotoxicol Environ Saf ; 270: 115920, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38171105

RESUMEN

Phthalates (PEs) are widely used plasticizers in polymer products, and humans are increasingly exposed to them. This study was designed to investigate the alleviative effect of phytochemicals quercetin (Que) against male reproductive toxicity caused by the mixture of three commonly used PEs (MPEs), and further to explore the underlying mechanism. Forty-eight male SD rats were randomly and evenly divided into control group, Que group, MPEs group and MPEs+Que group (n = 12); The oral exposure doses of MPEs and Que were 450 mg/kg/d and 50 mg/kg/d, respectively. After 91 days of continuous intervention, compared with control group, the testes weight, epididymis weight, serum sex hormones, and anogenital distance were significantly decreased in MPEs group (P < 0.05); Testicular histopathological observation showed that all seminiferous tubules were atrophy, leydig cells were hyperplasia, spermatogenic cells growth were arrested in MPEs group. Ultrastructural observation of testicular germ cells showed that the edges of the nuclear membranes were indistinct, and the mitochondria were severely damaged with the cristae disrupted, decreased or even disappeared in MPEs group. Immunohistochemistry and Western blot analysis showed that testicular CYP11A1, CYP17A1 and 17ß-HSD were up-regulated, while StAR, PIWIL1 and PIWIL2 were down-regulated in MPEs group (P < 0.05); However, the alterations of these parameters were restored in MPEs+Que group. The results indicated MPEs disturbed steroid hormone metabolism, and caused male reproductive injuries; whereas, Que could inhibit MPEs' male reproductive toxicity, which might relate to the restored regulation of steroid hormone metabolism.


Asunto(s)
Ácidos Ftálicos , Quercetina , Testículo , Humanos , Ratas , Masculino , Animales , Quercetina/farmacología , Ratas Sprague-Dawley , Hormonas Esteroides Gonadales/metabolismo , Esteroides/metabolismo , Testosterona , Proteínas Argonautas/metabolismo , Proteínas Argonautas/farmacología
2.
Anal Chem ; 95(33): 12459-12469, 2023 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-37566460

RESUMEN

To sensitively monitor trace amounts of alternariol (AOH) in fruits, a dual-mode aptamer sensor utilizing the dual-function nanomaterial PoPD/Ru-Au was developed. This sensor provides both electrochemical (EC) and electrochemiluminescence (ECL) signals, which can greatly avoid the potential false positive of the traditional single signal, thus enhancing the accuracy and reliability of detection results. Polyo-phenylenediamine (PoPD), known for its favorable EC response, can also assist in enhancing the ECL behavior of Ru-Au. Furthermore, Ru-Au demonstrates excellent ECL performance and effectively activates K2S2O8 to amplify the EC response of PoPD. The complementary effect of the two can effectively amplify the final detection signal. Additionally, the PoPD/Ru-Au nanomaterial exhibits excellent electrical conductivity, further enhancing the EC and ECL response signals. The experimental results demonstrate that the EC detection range of AOH was 0.01-100 ng/mL, while the ECL detection range was 0.001-100 ng/mL, both exhibiting a satisfactory linear relationship. Therefore, the mutual verification of the detection results can be highly realized, and the purpose of avoiding wrong detection can be achieved.

3.
Anal Chem ; 95(18): 7109-7117, 2023 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-37098252

RESUMEN

In this paper, a novel donor-acceptor pair was creatively proposed based on the principle of electrochemiluminescence resonance energy transfer (ECL-RET): luminol immobilized on polyethyleneimine (PEI)-functionalized manganese-based single-atom nanozymes (Mn SANE/PEI-luminol, donor) and a PtCu-grafted hollow metal polydopamine framework (PtCu/h-MPF, acceptor). A quenched ECL immunosensor was constructed for the ultrasensitive analysis of carcinoembryonic antigen (CEA). Mn SANE, as an efficient novel coreaction accelerator with the outstanding performance of significantly activating H2O2 to produce large amounts of ROS, was further modified by the coreactant PEI, which efficiently immobilized luminol to form a self-enhanced emitter. As a result, the electron transport distance was effectively shortened, the energy loss was reduced, and luminol achieved a high ECL efficiency. More importantly, PtCu-grafted h-MPF (PtCu/h-MPF) was proposed as a novel quencher. The UV-vis spectra of PtCu/h-MPF partially overlap with the ECL spectra of Mn SANE/PEI-luminol, which can effectively trigger the ECL-RET behavior between the donor and the acceptor. The multiple quenching effect on Mn SANE/PEI-luminol was achieved, which significantly improved the sensitivity of the immunosensor. The prepared immunosensor exhibited good linearity in the concentration range of 10-5 to 80 ng/mL. The results indicate that this work provides a new method for the early detection of CEA in clinical diagnosis.


Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Luminol , Antígeno Carcinoembrionario/análisis , Polietileneimina , Técnicas Biosensibles/métodos , Peróxido de Hidrógeno , Técnicas Electroquímicas/métodos , Mediciones Luminiscentes/métodos , Inmunoensayo/métodos , Límite de Detección
4.
Anal Chem ; 95(44): 16225-16233, 2023 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-37877873

RESUMEN

Compared with the accuracy of a single signal and the limitation of environmental applicability, the application value of dual-mode detection is gradually increasing. To this end, based on the photothermal effect of Ag/Co embedded N-rich mesoporous carbon nanomaterials (AgCo@NC NPs), we designed a dual-mode signal response system for the detection of α-fetoprotein (AFP). First, AgCo@NC NPs act as a photothermal immunoprobe that converts light energy into heat driven by a near-infrared (NIR) laser and obtains temperature changes corresponding to the analyte concentration on a hand-held thermal imager. In addition, this temperature recognition system can significantly improve the efficiency of Fenton-like reactions. AgCo@NC NPs act as peroxidase mimics to initiate the generation of poly N-isopropylacrylamide (PNIPAM, resistance enhancer) by cascade catalysis and the degradation of methylene blue (MB), thus enabling electrochemical testing. The dual-mode assay ranges from 0.01 to 100 and 0.001-10 ng/mL, with lower limits of detection (LOD) of 3.2 and 0.089 pg/mL, respectively, and combines visualization, portability, and high efficiency, opening new avenues for future clinical diagnostics and inhibitor studies.


Asunto(s)
Nanoestructuras , alfa-Fetoproteínas , Luz
5.
J Sci Food Agric ; 103(3): 1541-1549, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36197122

RESUMEN

BACKGROUND: Phthalates (PEs), such as butyl benzyl phthalate, dibutyl phthalate and di(2-ethylhexyl) phthalate, are one of the most widely used plasticizers, and humans are increasingly exposed to them. Phytochemical quercetin (Que) is a typical flavonoid with several biological effects, such as antioxidative and anti-inflammatory. The present study was designed to explore the effect of Que on testicular toxicity caused by the mixture of three commonly used PEs (MPEs), and the underlying mechanism. Forty male Sprague-Dawley rats were randomly and equally divided into five groups (n = 8). Rats in control the group were orally treated with the excipient. Rats in the MPEs group were orally administered with 900 mg kg-1 day-1 MPEs, whereas rats in the MPEs+L-Que, MPEs+M-Que and MPEs+H-Que groups were simultaneously treated with 900 mg kg-1 day-1 MPEs and, respectively, 10, 30 and 90 mg kg-1 day-1 Que for 30 days. RESULTS: Compared with the control group, the testes weight, epididymides weight, serum testosterone, luteinizing hormone, follicle-stimulating hormone and estradiol levels, and anogenital distance in the MPEs group were significantly decreased (P < 0.05). The testicular tissues were injured with atrophy of seminiferous tubules, hyperplasia of Leydig cells and arrest of spermatogenesis in the MPEs group. Testicular steroidogenic proteins (StAR, P450scc, CYP17A1 and 17ß-HSD, P450arom) were up-regulated, whereas P-element-induced wimpy testis proteins (PIWIL1 and PIWIL2) were down-regulated in the MPEs group (P < 0.05). However, the alterations of these parameters were inhibited in the MPEs+M-Que and MPEs+H-Que groups. CONCLUSION: MPEs disturbed steroid hormone metabolism and caused testicular injuries. Que could inhibit testicular toxicity of MPEs, which might relate to the improved regulation of steroid hormone metabolism. © 2022 Society of Chemical Industry.


Asunto(s)
Dietilhexil Ftalato , Testículo , Humanos , Ratas , Masculino , Animales , Quercetina/farmacología , Quercetina/metabolismo , Testosterona , Ratas Sprague-Dawley , Dietilhexil Ftalato/metabolismo , Dietilhexil Ftalato/farmacología , Proteínas Argonautas/metabolismo , Proteínas Argonautas/farmacología
6.
Mikrochim Acta ; 189(12): 441, 2022 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-36334136

RESUMEN

In order to solve the problems of unstable signal and fast decrease of response signal of traditional electroactive substances, we synthesized a new type of electroactive substances, so that they can cooperatively amplify the response signal of the immune sensor and further improve its sensitivity. The conductive organic ligand tetrahydroxy 1,4-benzoquinone (THQ) and Cu2+ were chelated to form a stable polymeric two-dimensional metal-organic framework material Cu-THQ. Cu-THQ is a new type of electroactive substance. Compared with the traditional electroactive substance, Cu-THQ not only has stronger Redox activity, but also better stability and biocompatibility. We carried out various electrochemical characterizations on Cu-THQ and further proved that the introduction of Cu2+ not only greatly enhanced the stability of THQ electrical signal, but also increased its signal response. The experimental results showed that the prepared immunosensor exhibited good linearity for the detection of carcinoembryonic antigen in the range 1 fg/mL to 40 ng/mL, with detection limits and sensitivity of 0.477 fg/mL and 14.81 µA/(ng/mL)/cm2, respectively.


Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Antígeno Carcinoembrionario , Anticuerpos Inmovilizados , Técnicas Electroquímicas/métodos , Técnicas Biosensibles/métodos , Nanopartículas del Metal/química , Límite de Detección , Inmunoensayo/métodos , Benzoquinonas
7.
Mikrochim Acta ; 189(9): 334, 2022 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-35970980

RESUMEN

To accomplish ultra-sensitive detection of alpha-fetoprotein(AFP), a novel electrochemical immunosensor using polydopamine-coated Fe3O4 nanoparticles (PDA@Fe3O4 NPs) as a smart label and polyaniline (PANI) and Au NPs as substrate materials has been created. The sensor has the following advantages over typical immunoassay technology: (1) The pH reaction causes PDA@Fe3O4 NPs to release Prussian blue (PB) prosoma while also destroying the secondary antibody label and immunological platform and lowering electrode impedance; (2) PB has a highly efficient catalytic effect on H2O2, allowing for the obvious amplification of electrical impulses; (3) PANI was electrodeposited on the electrode surface to avoid PB loss and signal leakage, which effectively absorbed and fixed PB while considerably increasing electron transmission efficiency. The sensor's detection limit was 0.254 pg·mL-1 (S/N = 3), with a detection range of 1 pg·mL-1 to 100 ng·mL-1. The sensor has a high level of selectivity, repeatability, and stability, and it is predicted to be utilized to detect AFP in real-world samples.


Asunto(s)
Técnicas Biosensibles , alfa-Fetoproteínas , Preparaciones de Acción Retardada , Técnicas Electroquímicas , Compuestos Férricos/química , Oro , Peróxido de Hidrógeno , Concentración de Iones de Hidrógeno , Inmunoensayo , Indoles/análisis , Indoles/química , Polímeros/química
8.
J Clin Monit Comput ; 33(3): 493-507, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29946994

RESUMEN

Current acute pain intensity assessment tools are mainly based on self-reporting by patients, which is impractical for non-communicative, sedated or critically ill patients. In previous studies, various physiological signals have been observed qualitatively as a potential pain intensity index. On the basis of that, this study aims at developing a continuous pain monitoring method with the classification of multiple physiological parameters. Heart rate (HR), breath rate (BR), galvanic skin response (GSR) and facial surface electromyogram were collected from 30 healthy volunteers under thermal and electrical pain stimuli. The collected samples were labelled as no pain, mild pain or moderate/severe pain based on a self-reported visual analogue scale. The patterns of these three classes were first observed from the distribution of the 13 processed physiological parameters. Then, artificial neural network classifiers were trained, validated and tested with the physiological parameters. The average classification accuracy was 70.6%. The same method was applied to the medians of each class in each test and accuracy was improved to 83.3%. With facial electromyogram, the adaptivity of this method to a new subject was improved as the recognition accuracy of moderate/severe pain in leave-one-subject-out cross-validation was promoted from 74.9 ± 21.0 to 76.3 ± 18.1%. Among healthy volunteers, GSR, HR and BR were better correlated to pain intensity variations than facial muscle activities. The classification of multiple accessible physiological parameters can potentially provide a way to differentiate among no, mild and moderate/severe acute experimental pain.


Asunto(s)
Dolor Agudo/diagnóstico , Enfermedad Crítica , Frecuencia Cardíaca , Monitoreo Fisiológico/métodos , Redes Neurales de la Computación , Dimensión del Dolor/métodos , Adulto , Área Bajo la Curva , Electromiografía , Femenino , Respuesta Galvánica de la Piel , Voluntarios Sanos , Calor , Humanos , Masculino , Curva ROC , Reproducibilidad de los Resultados , Respiración , Adulto Joven
9.
Molecules ; 24(14)2019 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-31340473

RESUMEN

The use of cellulose nanocrystals (CNC) in high performance coatings is attractive for micro-scale structures or device fabrication due to the anisotropic geometry, however CNC are insulating materials. Carbon nanotubes (CNT) are also rod-shaped nanomaterials that display high mechanical strength and electrical conductivity. The hydrophobic regions of surface-modified CNC can interact with hydrophobic CNT and aid in association between the two anisotropic nanomaterials. The long-range electrostatic repulsion of CNC plays a role in forming a stable CNT and CNC mixture dispersion in water, which is integral to forming a uniform hybrid film. At concentrations favorable for film formation, the multiwalled nanotubes + CNC mixture dispersion shows cellular network formation, indicating local phase separation, while the single-walled nanotube + CNC mixture dispersion shows schlieren texture, indicating liquid crystal mixture formation. Conductive CNT + CNC hybrid films (5-20 µm thick) were cast on glass microscope slides with and without shear by blade coating. The CNT + CNC hybrid films electrical conductivity increased with increasing CNT loadings and some anisotropy was observed with the sheared hybrid films, although to a lesser extent than what was anticipated. Percolation models were applied to model the hybrid film conductivity and correlate with the hybrid film microstructure.


Asunto(s)
Celulosa/química , Cristales Líquidos/química , Nanopartículas/química , Nanotubos de Carbono/química , Anisotropía , Celulosa/ultraestructura , Conductividad Eléctrica , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Cristales Líquidos/ultraestructura , Microscopía de Fuerza Atómica , Nanopartículas/ultraestructura , Nanotecnología/métodos , Nanotubos de Carbono/ultraestructura , Agua/química
10.
Biomacromolecules ; 19(8): 3435-3444, 2018 08 13.
Artículo en Inglés | MEDLINE | ID: mdl-29944348

RESUMEN

Cellulose nanocrystals hydrolyzed by hydrochloric acid and esterified by acetic acid produce acetylated cellulose nanocrystals (CNC-AA) with acetyl ester surface functional groups. While much attention has been paid to understanding the phase behavior (liquid crystal) of aqueous dispersions of sulfonated nanocrystals, relatively few studies have focused on CNC-AA dispersions. CNC-AA dispersions exhibit multiple phase regimes and markedly different phase behavior due to their lower surface charge. At concentrations above 5.0 × 10-4%vol, a decrease in the apparent diffusion coefficient indicates the onset of interparticle interactions and a transition from the dilute regime. From 0.003 to 0.31%vol, biphasic behavior is observed, consisting of a birefringent lower phase and disordered or isotropic upper phase. Small-angle neutron scattering was used to measure the growth of fractal structures with increasing concentration and indicates a two-dimensional assembly with short-range order in a plate-like assembled geometry. Above 0.31%vol, the dispersion transitions exhibit a cross-hatch birefringent texture, which is believed to exist as a fine-scale nematic that possesses frozen-in flow shear behavior, consistent with a glassy phase. This cross-hatch pattern is maintained in dried films, where atomic force microscopy and scanning electron microscopy reveal a layered sheet-like structure. Imaging also indicates that the basic unit of CNC-AA microstructure in the film consists of 0.5-1.5 µm scale aligned nanorod domains, which agrees with neutron scattering and the dimensions of each individual "hatch" in the birefringent texture observed by cross-polarized microscopy. The assembly of the nanorods into this layered structure and the fine-scale nematic birefringent cross-hatch texture is of significant fundamental interest, particularly since it differs greatly from cellulose nanocrystals with other surface chemistry and offers potential opportunities in other applications owing to the unique assembly.


Asunto(s)
Celulosa/análogos & derivados , Cristales Líquidos/química , Nanopartículas/química , Transición de Fase , Celulosa/química
11.
PLoS One ; 19(5): e0301828, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38820356

RESUMEN

COVID-19 has been a massive trade shock that has disrupted global trade, making the last few years a special phase. Even during normal times, epidemic diseases have acted as trade shocks in specific countries, albeit not to the same extent as COVID-19. For some trade shocks, the situation normalizes after the disease transmission is over; for some, it does not. Thus, specific countries can sometimes lose their original trade ratio due to trade diversion; that is, an epidemic disease could lead to unexpected industry restructuring. To examine this, based on data on 110 WHO members from 1996 to 2018, we use a fixed-effect panel model supported by the Hausman Test to empirically identify whether epidemic diseases can cause trade shocks and trade diversion. We find: First, epidemic disease can lead to negative shocks to a country's trade growth and its ratio of worldwide trade. Second, with a longer epidemic, the probability of the trade diversion effect increases. Our results hold even after considering country heterogeneity. This presents a considerable concern about the shock of COVID-19 lasting further. Many countries are not just facing the problem of temporary trade shocks, but also the challenge of trade diversions. In particular, the probability of trade diversions is increasing rapidly, especially for late-developed countries due to their lack of epidemic containment and vaccine-producing capabilities. Even middle and high income countries cannot ignore global industry chain restructuring. Forward-looking policies should be implemented in advance; it may be too late when long-term trade damage is shown.


Asunto(s)
COVID-19 , Comercio , Humanos , COVID-19/epidemiología , COVID-19/prevención & control , COVID-19/transmisión , SARS-CoV-2 , Epidemias/prevención & control , Pandemias/prevención & control
12.
Bioelectrochemistry ; 159: 108729, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38772096

RESUMEN

This study explores the principles of resonance energy transfer and adsorption modulation using composites of Cu2S-MPA/NGODs. These composites can efficiently control the quenching process of electrochemiluminescence (ECL). Mercaptopropionic acid (MPA) was added during the synthesis of Cu2S-MPA to enhance its attachment to nitrogen-doped graphene quantum dots (NGODs). The UV absorption peaks of NGODs coincided with the emission peaks of luminol ECL, enabling resonance energy transfer and enhancing the quenching capability of Cu2S-MPA. Meanwhile, there is another quenching strategy. When the readily reducible Cu+ ions underwent partial reduction to Cu when they were bound to NGODs. This weakened the electrocatalytic effect on reactive oxygen species (ROS) and had a detrimental impact on electron transfer. Under optimal conditions, the immunosensor ECL intensity decreased linearly with the logarithm of carcinoembryonic antigen (CEA) concentration in the range of 0.00001-40 ng/mL, with a detection limit of 0.269 fg/mL. The sensor was effectively utilized for the identification of CEA in actual serum samples.


Asunto(s)
Antígeno Carcinoembrionario , Cobre , Técnicas Electroquímicas , Grafito , Mediciones Luminiscentes , Puntos Cuánticos , Cobre/química , Puntos Cuánticos/química , Grafito/química , Antígeno Carcinoembrionario/sangre , Antígeno Carcinoembrionario/análisis , Mediciones Luminiscentes/métodos , Adsorción , Técnicas Electroquímicas/métodos , Límite de Detección , Ácido 3-Mercaptopropiónico/química , Humanos , Transferencia de Energía , Técnicas Biosensibles/métodos , Sulfuros
13.
Biomed Opt Express ; 15(3): 1486-1499, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38495712

RESUMEN

Studying brain activity during online learning will help to improve research on brain function based on real online learning situations, and will also promote the scientific evaluation of online education. Existing research focuses on enhancing learning effects and evaluating the learning process associated with online learning from an attentional perspective. We aimed to comparatively analyze the differences in prefrontal cortex (PFC) activity during resting, studying, and question-answering states in online learning and to establish a classification model of the learning state that would be useful for the evaluation of online learning. Nineteen university students performed experiments using functional near-infrared spectroscopy (fNIRS) to monitor the prefrontal lobes. The resting time at the start of the experiment was the resting state, watching 13 videos was the learning state, and answering questions after the video was the answering state. Differences in student activity between these three states were analyzed using a general linear model, 1s fNIRS data clips, and features, including averages from the three states, were classified using machine learning classification models such as support vector machines and k-nearest neighbor. The results show that the resting state is more active than learning in the dorsolateral prefrontal cortex, while answering questions is the most active of the three states in the entire PFC, and k-nearest neighbor achieves 98.5% classification accuracy for 1s fNIRS data. The results clarify the differences in PFC activity between resting, learning, and question-answering states in online learning scenarios and support the feasibility of developing an online learning assessment system using fNIRS and machine learning techniques.

14.
Biosens Bioelectron ; 252: 116151, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38402725

RESUMEN

Perylene diimide (PDI) is a readily reducible electron-deficient dye that exhibits strong photoluminescent properties, providing new opportunities for synthesizing novel electrochemiluminescence (ECL) emitters. In this study, ethylene glycol (EG) was used to induce the self-assembly of PDI supramolecules for the preparation of ultrathin EG-PDI nanosheets characterized by low crystallinity and weak stacking interaction. Notably, EG-PDI integrates luminescent and catalytic functions into one device, accelerating the interfacial electron transfer and the faster charge transfer kinetics of EG-PDI with K2S2O8. Furthermore, the narrow band gap of EG-PDI facilitates its excitation at an ultra-low potential (-0.3 V). To improve the efficiency of tumor marker analysis, multifunctional Au nanostars (ANS) was introduced both as an energy acceptor of the ECL system and a probe for the photothermal system. Dual-mode immunoassay have demonstrated superior analytical performance in detecting alpha-fetoprotein (AFP), meeting the requirements of modern clinical diagnostics in resource-limited environments.


Asunto(s)
Técnicas Biosensibles , Imidas , Perileno/análogos & derivados , Inmunoensayo , Glicoles de Etileno
15.
Bioelectrochemistry ; 156: 108626, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38128442

RESUMEN

By combining two different materials, metal-organic frameworks (MOF) and ß-cyclodextrins (ß-CD), a signal amplification electrochemical luminescence (ECL) immunosensor was constructed to realize the sensitive detection of AFP. The indium-based metal-organic framework (In-MOF) was used as the carrier of Ru(bpy)32+, and Ru(bpy)32+ was immobilized by In-MOF through suitable pore size and electrostatic interaction. At the same time, using host-guest recognition, ß-CD enriched TPA into the hydrophobic cavity for accelerating the electronic excitation of TPA, then, achieving the purpose of signal amplification. The signal amplification immunosensor structure is constructed among the primary antibody Ab1 connected to the Ru(bpy)32+@In-MOF modified electrode, AFP, BSA and the secondary antibody (Ab2) loaded with TPA-ß-CD. The immunosensor has a good linearity in the range of 10-5 ng/mL-50 ng/mL, and the low limit of detection (LOD) is 1.1 × 10-6 ng/mL. In addition, the electrochemiluminescence immunosensor that we designed has strong stability, good selectivity and repeatability, which provides a choice for the analysis of AFP.


Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Estructuras Metalorgánicas , beta-Ciclodextrinas , Nanopartículas del Metal/química , alfa-Fetoproteínas , Mediciones Luminiscentes , Inmunoensayo , Límite de Detección , Estructuras Metalorgánicas/química , Técnicas Electroquímicas
16.
Zhonghua Zhong Liu Za Zhi ; 35(4): 256-61, 2013 Apr.
Artículo en Zh | MEDLINE | ID: mdl-23985252

RESUMEN

OBJECTIVE: To evaluate the effect of capsaicin on nude mice xenografted with colorectal carcinoma cells, and to explore its mechanism of action. METHODS: A nude mouse model of colorectal cancer was established by subcutaneous inoculation of human colorectal carcinoma HT-29 cells. Terminal deoxynucleotidyl transferase-mediated nicked labeling assay (TUNEL) was undertaken to detect the cell proliferation and apoptosis in the xenograft tissue in nude mice. Immunohistochemical (IHC) staining and Western blot were used to detect the expression of HSP27, Cyt-C and active caspase-3. RESULTS: The tumor growth of the groups C10 and C20 was significantly slower than that of the group NS. The integrated optical density (IOD) of both the group C5 (2532.14 ± 578.11) and group C10 (6364.03 ± 1137.98) was significantly higher than that of the group NS (760.12 ± 238.05), (P < 0.05). The integrated optical density (IOD) of the group C20 was (15743.96 ± 1855.95), significantly higher than that of the groups C10, C5 and NS (all were P < 0.01). Immunohistochemistry showed that the cytoplasmic expression of HSP27 was strongly positive in the group NS, and significantly reduced with the increasing dose of capsaicin in the treated groups. The expression of active caspase-3 and Cyt-C in the group NS was weakly positive, and was significantly increased with the increasing dose of capsaicin in the groups C5 and C10 (P < 0.05), and the expression of active caspase-3 and Cyt-C of the group C20 was significantly higher than that of the groups C5, C10 and NS (P < 0.01). Western blot analysis showed that both the expressions of HSP27 of the group C5 (0.73 ± 0.05) and the group C10 (0.41 ± 0.03) were significantly lower than that of the group NS (P < 0.05). The expression of HSP27 of the group C20 (0.22 ± 0.06) was significantly lower than that of the groups C5, C10 and NS (P < 0.01). The expressions of active-caspase-3 and Cyt-C in the group C5 were (2.57 ± 0.34) and (2.03 ± 0.38), significantly higher than those of the group NS (P < 0.05). The expressions of active-caspase-3 and Cyt-C in the group C10 were (4.23 ± 0.45) and (3.13 ± 0.44), also significantly higher than those of the group NS (P < 0.05). The expressions of active-caspase-3 and Cyt-C in the group C20 were (5.78 ± 0.48) and (4.92 ± 0.52), significantly higher than those of the group C5, C10 and NS (P < 0.01). TUNEL analysis showed that there was a significant difference of cell apoptosis in comparison of each two groups. The higher dose of capsaicin was used, the more apoptosis was observed. CONCLUSIONS: Capsaicin can significantly inhibit the tumor growth and induce cell apoptosis in the colorectal carcinoma xenograft in nude mice. Its mechanism of action is possibly related with the down-regulation of HSP27 expression and up-regulation of expression of active caspase-3 and Cyt-C in the colorectal carcinoma xenograft in nude mice.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Capsaicina/farmacología , Caspasa 3/metabolismo , Grupo Citocromo c/metabolismo , Proteínas de Choque Térmico HSP27/metabolismo , Animales , Antineoplásicos Fitogénicos/administración & dosificación , Capsaicina/administración & dosificación , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Femenino , Células HT29 , Proteínas de Choque Térmico , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Chaperonas Moleculares , Trasplante de Neoplasias , Distribución Aleatoria , Carga Tumoral , Ensayos Antitumor por Modelo de Xenoinjerto
17.
Fa Yi Xue Za Zhi ; 29(6): 451-3, 2013 Dec.
Artículo en Zh | MEDLINE | ID: mdl-24665619

RESUMEN

Abstract: Suxamethonium chloride is a depolarizing muscle relaxant used in general anesthesia. In overdose, it causes adverse reactions such as bradycardia, arrhythmia, cardiac arrest, and death. The article reviews the progress on testing methods of suxamethonium chloride such as infrared spectroscopy, chemical color reaction, chemical titration, enzyme electrode, chromatography and mass spectrometry.


Asunto(s)
Anestesia General , Arritmias Cardíacas/inducido químicamente , Bradicardia/inducido químicamente , Paro Cardíaco/inducido químicamente , Fármacos Neuromusculares Despolarizantes/efectos adversos , Succinilcolina/efectos adversos , Técnicas Biosensibles , Cromatografía , Sobredosis de Droga , Humanos , Espectrometría de Masas , Fármacos Neuromusculares Despolarizantes/análisis , Espectrofotometría Infrarroja , Succinilcolina/análisis
18.
Mol Clin Oncol ; 19(3): 69, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37614374

RESUMEN

GREM1 is a secreted protein that antagonizes bone morphogenetic proteins (BMPs) and participates in critical biological processes, including embryonic development, organogenesis and tissue differentiation. Gremlin 1 (GREM1) is also an inhibitor of TGF-ß and a ligand for vascular endothelial growth factor receptor 2. In addition, GREM1 can induce cells, participate in the process of epithelial-mesenchymal transition, and then participate in tumor development. GREM1 has a variety of biological functions and can participate in the malignant progression of a variety of tumors through the BMP signaling pathway. GREM1 also can inhibit TGF-ß in some tumors, thereby inhibiting tumors, and its involvement in tumor development varies in different types of cancer. The present review examines the role and function of GREM1 in tumors. GREM1 is expressed in a variety of tumor types. GREM1 expression can affect the epithelial-mesenchymal transformation of tumor cells. GREM1 has been studied in breast and colon cancer, and its potential role is to promote cancer. However, in pancreatic cancer, which was found to act differently from other cancer types, overexpression of GREM1 inhibits tumor metastasis. The present review suggests that GREM1 can be a diagnostic and prognostic indicator. In future studies, the study of GREM1 based on single-cell sequencing technology will further clarify its role and function in tumors.

19.
IEEE J Biomed Health Inform ; 27(2): 944-955, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36367916

RESUMEN

Atrial fibrillation (AF) is one of the clinic's most common arrhythmias with high morbidity and mortality. Developing an intelligent auxiliary diagnostic model of AF based on a body surface electrocardiogram (ECG) is necessary. Convolutional neural network (CNN) is one of the most commonly used models for AF recognition. However, typical CNN is not compatible with variable-duration ECG, so it is hard to demonstrate its universality and generalization in practical applications. Hence, this paper proposes a novel Time-adaptive densely network named MP-DLNet-F. The MP-DLNet module solves the problem of incompatibility between variable-duration ECG and 1D-CNN. In addition, the feature enhancement module and data imbalance processing module are respectively used to enhance the perception of temporal-quality information and decrease the sensitivity to data imbalance. The experimental results indicate that the proposed MP-DLNet-F achieved 87.98% classification accuracy, and F1-score of 0.847 on the CinC2017 database for 10-second cropped/padded single-lead ECG fragments. Furthermore, we deploy transfer learning techniques to test heterogeneous datasets, and in the CPSC2018 12-lead dataset, the method improved the average accuracy and F1-score by 21.81% and 16.14%, respectively. Experimental results indicate that our method can update the constructed model's parameters and precisely forecast AF with different duration distributions and lead distributions. Combining these advantages, MP-DLNet-F can exemplify all kinds of varied-duration or imbalance medical signal processing problems such as Electroencephalogram (EEG) and Photoplethysmography (PPG).


Asunto(s)
Fibrilación Atrial , Humanos , Fibrilación Atrial/diagnóstico , Redes Neurales de la Computación , Procesamiento de Señales Asistido por Computador , Electrocardiografía/métodos , Fotopletismografía/métodos , Algoritmos
20.
Front Neurosci ; 17: 1138091, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37034171

RESUMEN

The connection between emotional states and physical health has attracted widespread attention. The emotional stress assessment can help healthcare professionals figure out the patient's engagement toward the diagnostic plan and optimize the rehabilitation program as feedback. It is of great significance to study the changes of physiological features in the process of emotional change and find out subset of one or several physiological features that can best represent the changes of psychological state in a statistical sense. Previous studies had used the differences in physiological features between discrete emotional states to select feature subsets. However, the emotional state of the human body is continuously changing. The conventional feature selection methods ignored the dynamic process of an individual's emotional stress in real life. Therefore, a dedicated experimental was conducted while three peripheral physiological signals, i.e., ElectroCardioGram (ECG), Galvanic Skin Resistance (GSR), and Blood Volume Pulse (BVP), were continuously acquired. This paper reported a novel feature selection method based on emotional state transition, the experimental results show that the number of physiological features selected by the proposed method in this paper is 13, including 5 features of ECG, 4 features of PPG and 4 features of GSR, respectively, which are superior to PCA method and conventional feature selection method based on discrete emotional states in terms of dimension reduction. The classification results show that the accuracy of the proposed method in emotion recognition based on ECG and PPG is higher than the other two methods. These results suggest that the proposed method can serve as a viable alternative to conventional feature selection methods, and emotional state transition deserves more attention to promote the development of stress assessment.

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