Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 61
Filtrar
Más filtros

País/Región como asunto
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
Anal Chem ; 95(26): 9967-9974, 2023 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-37341470

RESUMEN

A stable and reusable electrochemiluminescent (ECL) signal amplification strategy was proposed through a pyrene-based conjugated polymer (Py-CP) triggered self-circulating enhancement system. Specifically, the delocalized conjugated π-electrons of Py-CPs made it an excellent coreactant to arouse the initial ECL signal improvement of Ru(phen)32+, but the subsequent signal reduction was attributed to the consumption of Py-CPs, in which this stage was called the signal sensitization evoking phase (SSEP). Then, the maximum use of ECL luminescence of Ru(phen)32+ produced in the SSEP was made to irradiate the photosensitizer Py-CPs for in situ producing numerous ·OH, and a stronger and more stable ECL response stage defined as the signal sensitization stabilize phase was reached. Encouragingly, the incorporation of Nb2C MXene quantum dots with an exceptional physicochemical property not only foreshortens the SSEP for quickly acquiring a stable ECL signal but also introduces the photoacoustic (PA) transduce mechanism for achieving dual-signal outputting. Ultimately, the portable and miniaturized ECL-PA synergetic sensing platform based on the closed-bipolar electrode realized sensitive let-7a detection in a wide linear range from 10-9 to 10-2 nM with a low detection limit of 3.3 × 10-10 nM and also demonstrated good selectivity, excellent stability, and high reliability. The successful application of an innovative signal transduction mechanism and dexterous coupling modality will provide new insights for advancing the development of flexible analytical devices.


Asunto(s)
Técnicas Biosensibles , Neoplasias Pulmonares , Humanos , Polímeros/química , Reproducibilidad de los Resultados , Mediciones Luminiscentes , Técnicas Electroquímicas , Pirenos , Neoplasias Pulmonares/diagnóstico
2.
BMC Infect Dis ; 23(1): 619, 2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37730544

RESUMEN

BACKGROUND: Diabetes that develops in human immunodeficiency virus (HIV)-infected patients who receive antiretroviral therapy (ART) is usually type 2 diabetes mellitus (T2DM); however, autoimmune diabetes, such as type 1 diabetes mellitus (T1DM) can also develop in this population. After treatment with ART, patients might experience clinical deterioration following an increase in the CD4 cell count, which is termed immune reconstitution inflammatory syndrome (IRIS). Here, we describe an HIV-infected patient on ART who developed T1DMat due to IRIS, highlighting the clinical complexity in diagnosis and treatment. CASE PRESENTATION: A 36-year-old man infected with HIV had a nadir CD4 cell count of 15.53/µL before medication, which increased to 429.09/µL after 9 months of regular ART. The fasting serum glucose at 9 months was between 96 mg/dL and 117 mg/dL. After 11 months of ART, the patient was admitted to hospital for diabetic ketoacidosis (DKA) and Graves' disease (GD). Noninsulin antidiabetics (NIADs) were prescribed following the resolution of DKA. However, poor glycemic control was noted despite well-titrated NIADs. Further investigation demonstrated poor pancreatic beta cell function and elevated anti-glutamic acid decarboxylase (anti-GAD) and anti-tyrosine phosphatase-like insulinoma antigen 2 (anti-IA2) titers. According to the results, he was diagnosed with T1DM and received multiple daily injections(MDI) of insulin. The regimen of MDI was insulin degludec as basal insulin and insulin aspart as prandial insulin. After MDI therapy, his glycemic control was improved. CONCLUSION: In this case, T1DM was ascribed to IRIS. Although this phenomenon has been demonstrated in previous case reports, further study is necessary to realize the mechanism of this association. Therefore, we emphasize that when HIV-infected patients on ART experience an unstable blood glucose level and abnormal thyroid function, physicians should consider T1DM and GD associated with ART-induced IRIS to reduce the subsequent complications and more serious endocrine dysfunction.


Asunto(s)
Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Infecciones por VIH , Síndrome Inflamatorio de Reconstitución Inmune , Masculino , Humanos , Adulto , VIH , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Síndrome Inflamatorio de Reconstitución Inmune/diagnóstico , Síndrome Inflamatorio de Reconstitución Inmune/etiología , Hipoglucemiantes , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico
3.
Anal Chem ; 94(38): 13269-13277, 2022 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-36109852

RESUMEN

An electrochemiluminescent (ECL)-photoacoustic (PA) dual-signal output biosensor based on the modular optimization and wireless nature of a bipolar electrode (BPE) was constructed. To further simplify the detection process, the BPE structure was designed as three separate units: anode ECL collection, cathode catalytic amplification, and intermediate functional sensing units. Specifically, the anode unit was placed with Eosin Yellow, a cheap and effective ECL reagent, and the cathode unit was a laser-induced polyoxometalate-graphene electrode, which was helpful to enhance the anode ECL signal. The intermediate functional sensing unit consisted of a temperature-sensitive conductive film. Further, using a carbon nano-onion nanocomposite with excellent absorption performance in the near-infrared region as a signal tag not only leads to changes in the electrical conductivity of the film through heat transfer and thus affects the ECL signal but also produces a strong PA response. With this design, PA and ECL signals can be output simultaneously. This work not only realizes multiple modularization processes in the design of sensors but also implements the diversification of signal output modes, which will enrich the joint research field of ECL detection technology and other new detection methods.


Asunto(s)
Técnicas Biosensibles , Grafito , Neoplasias Ováricas , Aniones , Técnicas Biosensibles/métodos , Carbono , Técnicas Electroquímicas/métodos , Electrodos , Eosina Amarillenta-(YS) , Femenino , Grafito/química , Humanos , Mediciones Luminiscentes/métodos , Cebollas , Neoplasias Ováricas/diagnóstico , Polielectrolitos
4.
Mikrochim Acta ; 187(5): 303, 2020 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-32350687

RESUMEN

A self-enhanced electrochemiluminescent ratiometric immunoassay for zearalenone is described. A system composed of N-aminobutyl-N-ethylisoluminol (ABEI) and glutathione (GSH) produces a strong electrochemiluminescence (ECL) at an applied potential of 0.8 V, probably because of short electron transfer distance and reduced energy loss. The method also uses octahedral anatase mesocrystals (OAM) with a large specific surface facilitating immobilization of ABEI and GSH. Helical carbon nanotubes, possessing a large specific surface, superior mechanical stability, and excellent electrical conductivity which serve as a solid support, greatly enhanced the loading capacity for g-C3N4 nanosheets and horseradish peroxidase-labeled anti-antibody. The peroxidase accelerates the decomposition of H2O2 to produce reactive oxygen species (ROSs), amplifying the blue ECL of ABEI and the green ECL of g-C3N4. The ratiometric sandwich immunoassay (performed by the ratio of ECL intensity at - 1.3 V and 0.8 V) allows for sensitive and reliable determination of ZEN in a wide linear range from 1.0 × 10-4 ng/mL to 10 ng/mL. The method was successfully applied to the analysis of corn hazelnut samples for ZEN. Graphical abstract Schematic presentation of a self-enhanced electrochemiluminescent ratiometric immunosensor based on octahedral anatase mesocrystals (OAM) supported ABEI-glutathione (GSH) and g-C3N4 functionalized helical carbon nanotubes (HCNT) for zearalenone (ZEN) determination.

5.
Mikrochim Acta ; 187(1): 75, 2019 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-31863215

RESUMEN

An impedimetric immunoassay was designed for ultrasensitive determination of zearalenone (ZEN). It is making use of the peroxidase-like activity of strip-shaped Co3O4 (ssCo3O4) which catalyzes the oxidation of 4-chloro-1-naphthol to produce an insoluble precipitate in the presence of H2O2. The precipitate is electrically nonconductive and accumulates on the electrode, thereby retarding the electron transfer from the redox probe ferro/ferricyanide to the surface of electrode. This amplifies the impedimetric signal in accordance with logarithm of the concentration of ZEN. The electrode was further modified with TiO2 mesocrystals (TiO2 MCs) which improve the capture of more analytes and increase the performance of the immunoassay. Under optimized experimental condition, the impedimetric signal increased linearly with the logarithm of the ZEN concentration range between 0.1 fg·mL-1 to 10 pg·mL-1. The detection limit is of 33 ag· mL-1. Graphical abstractThis work describes an impedimetric immunoassay based on the use of strip-shaped Co3O4 that catalyzes the production of an insoluble precipitate in the presence of H2O2 on the surface of a glassy carbon electrode. The effect was used for signal amplification in an electrochemical immunoassay for zearalenone.


Asunto(s)
Cobalto/química , Inmunoensayo , Óxidos/química , Peroxidasa/química , Tiras Reactivas/química , Zearalenona/análisis , Cobalto/metabolismo , Electrodos , Humanos , Oxidación-Reducción , Óxidos/metabolismo , Tamaño de la Partícula , Peroxidasa/metabolismo , Tiras Reactivas/metabolismo , Propiedades de Superficie , Zearalenona/metabolismo
6.
Mikrochim Acta ; 186(9): 608, 2019 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-31392525

RESUMEN

An ultrasensitive competitive-type electrochemiluminescence immunoassay for the mycotoxin zearalenone is described. The method is based on the use of (a) a mimotope peptide that was selected from a phage displayed peptide library and used to substitute ZEN for designing the competitive assay; (b) NiFe2O4 nanotubes with large specific surface area loaded with the ECL probe Ru(bpy)32+; and (c) poly(vinylpyrrolidone) (PVP)-assisted synthesis of TiO2 mesocrystals that acts as the sensing platform and support for antibody immobilization. Under the optimized conditions and at an ECL working potential of 1.1 V, a linear response is found for ZEN in the 0.1 to 1.0 × 10-5 ng·mL-1 concentration range with a detection limit as low as 3.3 fg·mL-1. Graphical abstract An ultrasensitive competitive-type electrochemiluminescence (ECL) immunosensor based on mimotope peptide was constructed for the detection of Zearalenone.

8.
Mikrochim Acta ; 185(5): 277, 2018 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-29721681

RESUMEN

A dual-responsive sandwich-type immunosensor is described for the detection of interleukin 6 (IL-6) by combining electrochemiluminescent (ECL) and electrochemical (EC) detection based on the use of two kinds of TiO2 mesocrystal nanoarchitectures. A composite was prepared from TiO2 (anatase) mesocages (AMCs) and a carboxy-terminated ionic liquid (CTIL) and then placed on a glassy carbon electrode (GCE). In the next step, the ECL probe Ru(bpy)3(II) and antibody against IL-6 (Ab1) were immobilized on the GCE. Octahedral anatase TiO2 mesocrystals (OAMs) served as the matrix for immobilizing acid phosphatase (ACP) and secondary antibody (Ab2) labeled with horseradish peroxidase (HRP) to form a bioconjugate of type Ab2-HRP/ACP/OAMs. It was self-assembled on the GCE by immunobinding. 1-Naphthol, which is produced in-situ on the surface of the GCE due to the hydrolysis of added 1-naphthyl phosphate by ACP, is oxidized by HRP in the presence of added H2O2. This results in an electrochemical signal (typically measured at 0.4 V vs. Ag/AgCl) that increases linearly in the 10 fg·mL-1 to 90 ng·mL-1 IL-6 concentration range with a detection limit of 0.32 fg·mL-1. Secondly, the oxidation product of 1-naphthol quenches the ECL emission of Ru(bpy)32+. This leads to a decrease in ECL intensity which is linear in the 10 ag·mL-1 to 90 ng·mL-1 concentration range, with a detection limit of 3.5 ag·mL-1. The method exhibits satisfying selectivity and good reproducibility which demonstrates its potential in clinical testing and diagnosis. Graphical abstract A dual-responsive sandwich-type immunosensor was fabricated for the detection of interleukin 6 by combining electrochemiluminescence and electrochemical detection based on the use of two kinds of TiO2 mesocrystal nanoarchitectures.


Asunto(s)
Técnicas Biosensibles/métodos , Inmunoensayo/métodos , Interleucina-6/análisis , Nanoestructuras/química , Titanio/química , Electroquímica , Estudios de Factibilidad , Peroxidasa de Rábano Silvestre/metabolismo , Luminiscencia
10.
Anal Chem ; 88(11): 5775-82, 2016 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-27180822

RESUMEN

In this work, we first exposed that the application of p-type semiconductor, silver iodide-chitosan nanoparticle (SICNP), acted as peroxidase mimetic to catalyze the bioprecipitation reaction for signal-amplification photocathodic immunosensing of human interleukin-6 (IL-6). After immobilization of captured antibody onto a polyethylenimine-functionalized carbon nitride (CN) matrix, SICNPs as photoactive tags and peroxidase mimetics were labeled on secondary antibodies, which were subsequently introduced onto the sensing interface to construct sandwich immunoassay platform through antigen-antibody specific recognition. Due to the matched energy levels between CN and AgI, the photocurrent intensity and photostability of SICNP were dramatically improved with rapid separation and transportation of photogenerated carriers. Moreover, the insoluble product in effective biocatalytic precipitation reaction served as electron acceptor to scavenge the photoexcited electron, leading to great amplification of the photocurrent signal of SICNP again. With the help of multiamplification processes, this photocathodic immunosensor presented a turn-on photoelectrochemical performance for IL-6, which showed wide linear dynamic range from 10(-6) to 10 pg/mL with the ultralow detection limit of 0.737 ag/mL. This work also performed the promising application of SICNP in developing an ultrasensitive, cost-effective, and enzyme-free photocathodic immunosensor for biomarkers.


Asunto(s)
Anticuerpos/inmunología , Biocatálisis , Quitosano/química , Inmunoensayo/métodos , Interleucina-6/inmunología , Yoduros/química , Nanopartículas/química , Procesos Fotoquímicos , Compuestos de Plata/química , Anticuerpos Inmovilizados/inmunología , Reacciones Antígeno-Anticuerpo , Catálisis , Electrodos , Humanos , Inmunoensayo/instrumentación
11.
Anal Chem ; 88(19): 9532-9538, 2016 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-27584697

RESUMEN

It is a great challenge to fabricate multiplex and convenient photoelectrochemical biosensors for ultrasensitive determination of biomarkers. Herein, a fascinating potentiometric addressable photoelectrochemical biosensor was reported for double biomarkers' detection by varying the applied bias in the detection process. In this biosensor, the nanocomposite of cube anatase TiO2 mesocrystals and polyamidoamine dendrimers modified a dual disk electrode as an excellent photoelectrochemical sensing matrix. Subsequently, two important biomarkers in serum for prostate cancer, prostate-specific antigen and human interleukin-6, were immobilized onto the different disks of modified electrode via glutaraldehyde bridges. Then another two photosensitizers, graphitic-carbon-nitride-labeled and CS-AgI-labeled different antibodies, were self-assembled onto the electrode surface by a corresponding competitive immune recognition reaction. The change in photocurrent with the target antigen concentration at different critical voltages enables us to selectively and quantitatively determine targets. The results demonstrated that this potentiometric addressable photoelectrochemical biosensing strategy not only has great promise as a new point-of-care diagnostic tool for early detection of prostate cancer but also can be conveniently expanded to multiplex biosensing by simply change biomarkers. More importantly, this work provides an unambiguous operating guideline of multiplex photoelectrochemical immunoassay.


Asunto(s)
Biomarcadores/análisis , Técnicas Biosensibles/métodos , Interleucina-6/análisis , Calicreínas/análisis , Potenciometría/métodos , Antígeno Prostático Específico/análisis , Dendrímeros/química , Electrodos , Humanos , Límite de Detección , Nanocompuestos/química , Poliaminas/química , Titanio/química
12.
Analyst ; 140(10): 3514-20, 2015 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-25832982

RESUMEN

A visible light responsive photocatalytic hybrid with excellent photoelectrochemical activity was first fabricated via the self-assembly of Au nanorods onto poly(l-cysteine) modified graphitic carbon nitride nanosheets. Herein, layered structural graphitic carbon nitride nanosheets with a proper band gap, high stability, and nontoxicity, as a photoactive material, demonstrate a high photocatalytic activity. Furthermore, the incorporation of multifunctional Au nanorods gave the hybrid a Schottky barrier and localized surface plasmonic resonance, which considerably enhanced the separation of the photo-excited electrons and holes, resulting in increased photoelectrochemical performance. As a proof of concept, mercapto-beta-cyclodextrin as a bionic recognition device was introduced into the hybrid to selectively detect naringin on the basis of the dramatic decreasing of photocurrent. The visible-light driven photoelectrochemical sensor exhibited excellent analytical performance, including high sensitivity, good selectivity and wide linear range from 1 × 10(-4) to 1 × 10(-10) M.

13.
Analyst ; 140(2): 582-9, 2015 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-25426499

RESUMEN

Herein, simple molecular recognition sites for formaldehyde were designed on electrospun polymer nanofibers. In order to improve the conductivity of the electrospun polymer nanofibers, carbon nanotubes were introduced into the resulting nanofibers. By employing these functionalized nanocomposite fibers to fabricate a biomimetic sensor platform, an obvious change caused by recognition between recognition sites and formaldehyde molecules was monitored through electrochemical impedance spectroscopy (EIS). The experimental conditions were optimized and then a quantitative method for formaldehyde sensing in low concentration was established. The relative results demonstrated that the sensor based on biomimetic recognition nanofibers displays an excellent recognition capacity toward formaldehyde. The linear response range of the sensor was between 1 × 10(-6) mol L(-1) and 1 × 10(-2) mol L(-1), with the detection limit of 8 × 10(-7) mol L(-1). The presented research provided a fast, feasible and sensitive method for formaldehyde with good anti-interference capabilities and good stability, which could meet the practical requirement for formaldehyde assay.


Asunto(s)
Materiales Biomiméticos/química , Técnicas Biosensibles/métodos , Espectroscopía Dieléctrica/métodos , Formaldehído/análisis , Límite de Detección , Nanocompuestos/química , Nanofibras/química , Nanotubos de Carbono/química
14.
Anal Chem ; 86(13): 6418-24, 2014 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-24884080

RESUMEN

A ternary hybrid was developed through interaction between a hierarchical-ordered TiO2 and a thiol group that was obtained by in situ chemical polymerization of L-cysteine on the carbon nanohorn (CNH) superstructure modified electrode. Herein, unique-ordered TiO2 superstructures with quasi-octahedral shape that possess high crystallinity, high porosity, oriented subunit alignment, very large specific surface area, and superior photocatalytic activity were first introduced as a photosensitizer element in the photoelectrochemical determination. Additionally, the assembly of hierarchical-structured CNHs was used to provide an excellent electron-transport matrix to capture and transport an electron from excited anatase to the electrode rapidly, hampering the electron-hole recombination effectively, resulting in improved photoelectrochemical response and higher photocatalytic activity in the visible light region. Owing to the dependence of the photocurrent signal on the concentration of electron donor, 4-methylimidozal, which can act as a photogenerated hole scavenger, an exquisite photoelectrochemical sensor was successfully fabricated with a wide linear range from 1 × 10(-4) to 1 × 10(-10) M, and the detection limit was down to 30 pM. The low applied potential of 0.2 V was beneficial to the elimination of interference from other reductive species that coexisted in the real samples. More importantly, the mesocrystal was first introduced in the fabricating of a biosensor, which not only opens up a new avenue for biosensors manufactured based on mesocrystal materials but also provides beneficial lessons in the research fields ranging from solar cells to photocatalysis.


Asunto(s)
Carbono/química , Técnicas Electroquímicas/métodos , Imidazoles/análisis , Nanoestructuras/química , Titanio/química , Cristalización , Electrodos , Contaminación de Alimentos/análisis , Luz , Límite de Detección , Procesos Fotoquímicos
15.
Heliyon ; 10(6): e28333, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38524572

RESUMEN

Brown tumors (osteitis fibrosa cystica) are rare pathognomonic signs that occur in patients with primary hyperparathyroidism (PHPT). Brown tumors can exist in multiple bones and can easily be misdiagnosed as a metastatic tumor or multiple myeloma. It is also localized in the forearm, humerus, and leg. The symptoms of hypercalcemia, pathologic fracture, and bodyweight loss may increase the diagnostic difficulty of brown tumors because multiple myeloma and bone metastasis also show the same symptoms. We studied a 68-year-old woman who had experienced unusual bodyweight loss in the past 6 months (56kg-40kg) and bone pain. She went to the hospital after a fall with a complaint of bone pain. An X-ray revealed a left bubbly-like cystic change and multiple fractures at the left ulna midshaft. Upon investigation, the level of intact parathyroid hormone was ascertained to be 1800 (normal: 10-60) pg/ml. Microscopically, the tumor demonstrated a benign bone lesion and was compatible with osteitis fibrosa cystica due to PHPT. The parathyroid scan (Tc-99 m sestamibi) indicated right parathyroid hyperplasia, which was later confirmed by a parathyroidectomy. She was diagnosed with osteitis fibrosa cystica associated with PHPT due to a parathyroid adenoma. PHPT can be presented with multiple fractures, bone pain, and bodyweight loss. Therefore, if a patient presents these symptoms, PHPT should be considered.

16.
Anal Bioanal Chem ; 405(1): 259-66, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23086086

RESUMEN

This study establishes a method, using different buffer conductivities and large-volume sample stacking (LVSS)-sweeping capillary electrophoresis, for analysis of carbamazepine (CBZ) and its five metabolites in serum. The capillary (50/60 cm) was filled with a high concentration of background electrolyte (150 mM phosphate, pH 3.5, containing 15 % methanol), followed by a large volume of samples (10 psi, 20 s) with low-concentration buffers (5 mM phosphate, pH 3.5, with 5 % methanol). When high voltage was applied (-20 kV), the sodium dodecyl sulfate (SDS) started to sweep the analytes to an outlet. Meanwhile, the analytes decelerated at the boundary between low- and high-conductivity buffers. Finally, a narrow sample zone was formed. The procedure of sweeping and separation was simultaneously carried out by a sweeping buffer (150 mM phosphate, pH 3.5) with 15% methanol and 50 mM SDS added, and the detection was performed by UV at 214 nm. The method was validated for linearity (r >/= 0.997), precision, and accuracy. The calibration curves were established for CBZ and its five metabolites between 0.03-25 and 0.03-3 µg/mL. The limits of detection (S/N = 3) were 0.01 µg/mL for each analyte. Compared with simple MEKC (0.5 psi, 5 s), this system can improve the sensitivity about 300-fold. Finally, this method was successfully applied to five patients, who had taken 200 mg CBZ daily, and CBZ levels were found to be from 3.72 to 5.82 µg/mL.


Asunto(s)
Carbamazepina/análisis , Electroforesis Capilar/métodos , Calibración , Carbamazepina/sangre , Carbamazepina/metabolismo , Técnicas de Química Analítica , Conductividad Eléctrica , Humanos , Concentración de Iones de Hidrógeno , Inmunoensayo/métodos , Modelos Lineales , Fosfatos/análisis , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Factores de Tiempo
17.
Luminescence ; 28(4): 456-60, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24073426

RESUMEN

A new strategy for the construction of a sensitive and stable electrochemiluminescent platform based on titanate nanotubes (TNTs) and Nafion composite modified electrode for luminol is described, TNTs contained composite modified electrodes that showed some photocatalytic activity toward luminol electrochemiluminescence emission, and thus could dramatically enhance luminol light emission. This extremely sensitive and stable platform allowed a decrease of the experiment electrochemiluminescence luminol reagent. In addition, in luminol solution at low concentrations, we compared the capabilities of a bare glassy carbon electrode with the TNT composite modified electrode for hydrogen peroxide detection. The results indicated that compared with glassy carbon electrode this platform was extraordinarily sensitive to hydrogen peroxide. Therefore, by combining with an appropriate enzymatic reaction, this platform would be a sensitive matrix for many biomolecules.


Asunto(s)
Carbono/química , Técnicas Electroquímicas , Luminiscencia , Luminol/química , Nanotubos/química , Titanio/química , Electrodos , Vidrio/química
18.
Sensors (Basel) ; 14(1): 458-67, 2013 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-24379050

RESUMEN

A surface plasmon resonance sensor for Mycobacterium tuberculosis (MTB) deoxyribonucleic acid (DNA) is developed using repeatable telecommunication wavelength modulation based on optical fiber communications laser wavelength and stability. MTB DNA concentrations of 1 µg/mL and 10 µg/mL were successfully demonstrated to have the same spectral half-width in the dip for optimum coupling. The sensitivity was shown to be -0.087 dB/(µg/mL) at all applied telecommunication wavelengths and the highest sensitivity achieved was 115 ng/mL without thiolated DNA immobilization onto a gold plate, which is better than the sensor limit of 400 ng/mL possible with commercial biosensor equipment.


Asunto(s)
ADN Bacteriano/análisis , Mycobacterium tuberculosis/genética , Resonancia por Plasmón de Superficie/métodos , Telecomunicaciones
19.
BMC Med Genomics ; 16(1): 118, 2023 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-37245000

RESUMEN

BACKGROUND: Marfan syndrome (MFS) is a rare autosomal dominant connective tissue disorder affecting the cardiovascular, skeletal, and ophthalmic systems. This report aimed to describe a novel genetic background and treatment prognosis of MFS. CASE PRESENTATION: A proband was initially diagnosed with bilateral pathologic myopia and suspected MFS. We performed whole exome sequencing and found a pathogenic nonsense FBN1 mutation in the proband, which confirmed the diagnosis of MFS. Notably, we identified a second pathogenic nonsense mutation in SDHB, which increased the risk of tumours. In addition, the proband karyotype was X trisomy, which may cause X trisomy syndrome. At the 6-month follow-up after posterior scleral reinforcement surgery, the proband's visual acuity improved significantly; however, myopia was still progressing. CONCLUSIONS: We report a rare case of MFS with a X trisomy genotype, a mutation in FBN1 and a mutation in SDHB for the first time, and our findings could be helpful for the clinical diagnosis and treatment of this disease.


Asunto(s)
Síndrome de Marfan , Miopía , Humanos , Síndrome de Marfan/genética , Síndrome de Marfan/diagnóstico , Síndrome de Marfan/patología , Trisomía/genética , Fibrilina-1/genética , Mutación , Codón sin Sentido , Succinato Deshidrogenasa/genética
20.
Arch Endocrinol Metab ; 67(2): 172-178, 2023 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-36651704

RESUMEN

Objective: Papillary thyroid carcinoma (PTC) accounts for approximately 85%-90% of all thyroid cancers. Of the iodine-metabolizing genes, BRAFV600E is a highly specific target for PTC and may have a reciprocal causative relationship with iodide-metabolizing genes. Materials and methods: In this study, we performed a data analysis of selected quantitative studies to determine the relationship between iodine nutritional status and the prevalence of the BRAF600E mutation in patients with PTC. Five studies were selected for meta-analysis based on the selection criteria. Results: A total of 2,068 patients were divided into three groups: low (urinary iodine concentration [UIC] < 100 µg/L), adequate (UIC 100-200 µg/L), and high (UIC ≥ 200 µg/L). The results were obtained using RevMan software, and the pooled odds ratios (ORs) were calculated using Mantel-Haenszel statistics with a 95% confidence interval (CI). The OR for the prevalence of the BRAFV600E mutation between the high and adequate groups was 1.25 (95% CI 0.64-2.43, p = 0.51), and the OR between the low and adequate groups was 0.98 (95% CI 0.42-2.31, p = 0.96). The BRAFV600E mutation risk did not change significantly at different levels of iodine nutrition (p = 0.33) in statistical analyses. Conclusion: We conducted preliminary research on dietary iodine intake and the BRAFV600E mutation in PTC. The results suggested that abnormal iodine intake might not directly influence the prevalence of the BRAFV600E mutation in these patients. Further research into the associations between dietary iodine intake and the BRAFV600E mutation in PTC, including the underlying mechanisms, is required.


Asunto(s)
Yodo , Neoplasias de la Tiroides , Humanos , Cáncer Papilar Tiroideo/genética , Cáncer Papilar Tiroideo/complicaciones , Estado Nutricional , Prevalencia , Neoplasias de la Tiroides/epidemiología , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/patología , Mutación/genética
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA