Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Biol Chem ; : 107494, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38925326

RESUMO

The commitment of stem cells to differentiate into osteoblasts is a highly regulated and complex process that involves the coordination of extrinsic signals and intrinsic transcriptional machinery. While rodent osteoblastic differentiation has been extensively studied, research on human osteogenesis has been limited by cell sources and existing models. Here, we systematically dissect hPSC-derived osteoblasts to identify functional membrane proteins and their downstream transcriptional networks involved in human osteogenesis. Our results reveal an enrichment of type II transmembrane serine protease CORIN in humans but not rodent osteoblasts. Functional analyses demonstrated that CORIN depletion significantly impairs osteogenesis. Genome-wide ChIP enrichment and mechanistic studies show that p38 MAPK-mediated CEBPD upregulation is required for CORIN-modulated osteogenesis. Contrastingly, the type I transmembrane heparan sulfate proteoglycan SDC1 enriched in MSCs exerts a negative regulatory effect on osteogenesis through a similar mechanism. ChIP-seq, bulk and single-cell transcriptomes, and functional validations indicated that CEBPD plays a critical role in controlling osteogenesis. In summary, our findings uncover previously unrecognized CORIN-mediated CEBPD transcriptomic networks in driving human osteoblast lineage commitment.

2.
Biosensors (Basel) ; 13(9)2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37754095

RESUMO

The coronavirus disease (COVID-19) pandemic has increased pressure to develop low-cost, compact, user-friendly, and ubiquitous virus sensors for monitoring infection outbreaks in communities and preventing economic damage resulting from city lockdowns. As proof of concept, we developed a wearable paper-based virus sensor based on a molecular imprinting technique, using a conductive polyaniline (PANI) polymer to detect the lentivirus as a test sample. This sensor detected the lentivirus with a 4181 TU/mL detection limit in liquid and 0.33% to 2.90% detection efficiency in aerosols at distances ranging from 30 cm to 60 cm. For fabrication, a mixture of a PANI monomer solution and virus were polymerized together to form a conductive PANI sensing element on a polyethylene terephthalate (PET) paper substrate. The sensing element exhibited formation of virus recognition sites after the removal of the virus via ultrasound sonication. A dry measurement technique was established that showed aerosol virus detection by the molecularly imprinted sensors within 1.5 h of virus spraying. This was based on the mechanism via which dispensing virus droplets on the PANI sensing element induced hybridization of the virus and molecularly imprinted virus recognition templates in PANI, influencing the conductivity of the PANI film upon drying. Interestingly, the paper-based virus sensor was easily integrated with a wearable face mask for the detection of viruses in aerosols. Since the paper sensor with molecular imprinting of virus recognition sites showed excellent stability in dry conditions for long periods of time, unlike biological reagents, this wearable biosensor will offer an alternative approach to monitoring virus infections in communities.

3.
Sensors (Basel) ; 20(24)2020 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-33352634

RESUMO

Perfluorinated compounds like perfluorooctanesulfonic acid (PFOS) are synthetic water pollutants and have accumulated in environments for decades, causing a serious global health issue. Conventional assays rely on liquid chromatography and mass spectroscopy that are very expensive and complicated and thus limit the large-scale monitoring of PFOS in wastewater. To achieve low-cost and accurate detection of PFOS, we designed a paper-based sensor with molecularly imprinted polyaniline electrodes that have recognition sites specific to PFOS. The calibration curve of resistivity ratios as a function of PFOS concentrations has a linear range from 1 to 100 ppt with a coefficient of determination of 0.995. The estimated limit of detection is 1.02 ppt. We also investigated attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS) spectra of the surface of the polyaniline (PANI) electrodes to propose the potential recognition sites in polyaniline matrix and the detection mechanism. This electrical paper sensor with low cost and excellent sensitivity and selectivity provides the potential for large-scale monitoring of wastewater.

4.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 4097-4100, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018899

RESUMO

A low-cost and enzyme-free glucose paper sensor is presented as a promising alternative to glucose test strips. This paper-based glucose sensor is prepared with molecularly imprinted (MIP) polyaniline (PANI) electrode. The determination of glucose concentrations was studied by the impedance change of the paper sensor before and after the blood samples dispensing at a low frequency. A comparison of the linear and polynomial regression was applied to analyze the impedance ratio as a function of glucose concentrations. The proposed glucose paper sensor showed a limit of detection (LoD) of 1.135 mM. This novel and non-enzymatic paper sensor suggests a low-cost glucose test assay and can improve the quality of routine testing for diabetic patients.


Assuntos
Impressão Molecular , Eletrodos , Glucose , Humanos , Sistemas de Infusão de Insulina , Limite de Detecção
5.
Sensors (Basel) ; 20(4)2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32079357

RESUMO

For the hundreds of millions of worldwide diabetic patients, glucose test strips are the most important and commonly used tool for monitoring blood glucose levels. Commercial test strips use glucose oxidases as recognition agents, which increases the cost and reduces the durability of test strips. To lower the cost of glucose sensors, we developed a paper-based electrical sensor with molecularly imprinted glucose recognition sites and demonstrated the determination of various glucose concentrations in bovine blood solutions. The sensing electrode is integrated with molecular recognition sites in the conductive polymer. A calibration graph as a function of glucose concentration in aqueous solution was acquired and matched with a correlation coefficient of 0.989. We also demonstrated the determination of the added glucose concentrations ranging from 2.2 to 11.1 mM in bovine blood samples with a linear correlation coefficient of 0.984. This non-enzymatic glucose sensor has the potential to reduce the health care cost of test strips as well as make glucose sensor test strips more accessible to underserved communities.


Assuntos
Compostos de Anilina/química , Técnicas Biossensoriais , Glucose/isolamento & purificação , Impressão Molecular , Técnicas Eletroquímicas , Eletrodos , Glucose/química , Ouro/química , Humanos
6.
J Mater Chem B ; 1(16): 2178-2189, 2013 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-32260851

RESUMO

Silver nanoparticles (AgNPs) exhibit size-dependent bactericidal activity. They are, however, subject to aggregation when added to most hydrophobic polymers. In this study, a surfactant-modified delaminated clay (surfactant-capped nanosilicate platelets, or "NSQ") was employed to be a nanocarrier for AgNPs. The nanohybrid of AgNPs and NSQ ("AgNP/NSQ") in aqueous solution showed remarkable bactericidal effect as well as negligible cytotoxicity and immune response at a concentration of 10 ppm. Poly(carbonate)urethane (PCU) with different hard/soft segment ratios was synthesized and used in the preparation of the nanocomposites, PCU-AgNP/NSQ. Based on TEM observation, AgNP/NSQ was well dispersed in the resulting nanocomposites. The reinforcing effects of AgNP/NSQ in nanocomposites were distinct for PCU with different hard/soft segment ratios. The phase-separated structure of PCU-AgNP/NSQ nanocomposites was investigated by small-angle X-ray scattering (SAXS). PCU-AgNP/NSQ containing 75 ppm of Ag demonstrated superior microbiostatic effect, as well as better biodurability and lower foreign body reaction than the commercial Pellethane 2363-80A.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...