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1.
Anal Chem ; 96(18): 7145-7154, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38656793

RESUMEN

Immunoassays serve as powerful diagnostic tools for early disease screening, process monitoring, and precision treatment. However, the current methods are limited by high costs, prolonged processing times (>2 h), and operational complexities that hinder their widespread application in point-of-care testing. Here, we propose a novel centrifugo-pneumatic reciprocating flowing coupled with spatial confinement strategy, termed PRCM, for ultrafast multiplexed immunoassay of pathogens on a centrifugal microfluidic platform. Each chip consists of four replicated units; each unit allows simultaneous detection of three targets, thereby facilitating high-throughput parallel analysis of multiple targets. The PRCM platform enables sequential execution of critical steps such as solution mixing, reaction, and drainage by coordinating inherent parameters, including motor rotation speed, rotation direction, and acceleration/deceleration. By integrating centrifugal-mediated pneumatic reciprocating flow with spatial confinement strategies, we significantly reduce the duration of immune binding from 30 to 5 min, enabling completion of the entire testing process within 20 min. As proof of concept, we conducted a simultaneous comparative test on- and off-the-microfluidics using 12 negative and positive clinical samples. The outcomes yielded 100% accuracy in detecting the presence or absence of the SARS-CoV-2 virus, thus highlighting the potential of our PRCM system for multiplexed point-of-care immunoassays.


Asunto(s)
COVID-19 , Centrifugación , SARS-CoV-2 , Inmunoensayo/métodos , Inmunoensayo/instrumentación , SARS-CoV-2/aislamiento & purificación , Centrifugación/instrumentación , COVID-19/diagnóstico , COVID-19/virología , Humanos , Técnicas Analíticas Microfluídicas/instrumentación , Dispositivos Laboratorio en un Chip
2.
Nano Lett ; 24(1): 417-423, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38149580

RESUMEN

Spectrally stable pure-red perovskite quantum dots (QDs) with low lead content are essential for high-definition displays but are difficult to synthesize due to QD self-purification. Here, we make use of entropy-driven quantum-confined pure-red perovskite QDs to fabricate light-emitting diodes (LEDs) that have low toxicity and are efficient and spectrum-stable. Based on experimental data and first-principles calculations, multiple element alloying results in a 60% reduction in lead content while improving QD entropy to promote crystal stability. Entropy-driven QDs exhibit photoluminescence with 100% quantum yields and single-exponential decay lifetimes without alteration of their morphology or crystal structure. The pure-red LEDs utilizing entropy-driven QDs have spectrally stable electroluminescence, achieving a brightness of 4932 cd/m2, a maximum external quantum efficiency of over 20%, and a 15-fold longer operational lifetime than the CsPbI3 QD-based LEDs. These achievements demonstrate that entropy-driven QDs can mitigate local compositional heterogeneity and ion migration.

3.
Microvasc Res ; 150: 104589, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37481161

RESUMEN

In our previous report, we presented evidence supporting the role of miR-574-3p in downregulating the expression of cullin 2 (CUL2) in gastric cancer (GC) cells. Expanding on those findings, the present study aims to confirm the direct interaction between miR-574-3p and the 3' untranslated region (3'UTR) of CUL2, which leads to the suppression of CUL2 expression and destabilization of the VCBCR complex. Based on these discoveries, we propose a novel pathway involving miR-574-3p, HIF-1α, and VEGF that contributes to angiogenesis. Through a series of meticulous experiments, we successfully validate this hypothesis. Specifically, our observations indicate that overexpression of miR-574-3p in GC cells induces an upregulation of HIF-1α and VEGF, resulting in enhanced proliferation, migration, invasion, and tube formation of HUVEC cells. Furthermore, employing a mouse model, we demonstrate that miR-574-3p facilitates the recruitment of endothelial cells towards matrigel xenografts. Additionally, we note a parallel increase in miR-574-3p and HIF-1α levels across multiple cell lines (including AGS, SGC-7901, Hela, and 293T cells) subjected to hypoxic conditions (2 % O2 or CoCl2 treatment), as well as in the myocardial muscles of sodium nitrite-induced hypoxic mice. Further investigations reveal that HIF-1α upregulates miR-574-3p expression by directly binding to the miR-574 promoter. Collectively, these findings strongly support the existence of a positive feedback loop between miR-574-3p and HIF-1α, which facilitates angiogenesis under hypoxic conditions.


Asunto(s)
MicroARNs , Factor A de Crecimiento Endotelial Vascular , Animales , Humanos , Ratones , Línea Celular Tumoral , Proliferación Celular , Retroalimentación , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Hipoxia , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo
4.
Mol Biol Rep ; 50(8): 6627-6641, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37358765

RESUMEN

BACKGROUND: Glutamine metabolism is critical for development of hepatocellular carcinoma (HCC), which makes it a novel promising treatment target. However, clinical evidence suggested glutamine withdrawal therapy does not achieved the desired tumor suppression. Therefore, it is valuable to investigate the survival mechanisms of tumors with glutamine deprivation. METHODS: The HCC cells were cultured in glutamine-free medium or supplemented with glutamine metabolites or ferroptosis inhibitors. The parameters related to ferroptosis and the activity of GSH synthesis-related enzymes of the HCC cells were detected by corresponding kits. The expressions of glutamate oxaloacetate transaminase 1 (GOT1), c-Myc and Nrf2 were detected by western blot and qRT-PCR. The chromatin immunoprecipitation and luciferase reporter assays were performed to investigate the correlation between c-Myc and GOT1. The siRNAs of c-Myc and GOT1 were used to explore their roles in GSH (GSH) synthesis and ferroptosis in vitro and in vivo. RESULTS: Glutamine deprivation-induced ferroptosis did not completely inhibit HCC cells proliferation. Glutamine deprivation activated the expression of c-Myc, which promoted the transcription of GOT1 and Nrf2, consequently maintaining the GSH synthesis and inhibiting ferroptosis. In addition, combined inhibition of GOT1 with glutamine deprivation could result in better inhibition of HCC in vitro and in vivo. CONCLUSIONS: In our work, the results indicate that GOT1 induced by c-Myc may play an important role in combating ferroptosis due to glutamine deprivation, making it a significant target in glutamine withdrawal therapy. This study provides a theoretical foundation for the clinical targeted therapy for HCC.


Asunto(s)
Carcinoma Hepatocelular , Ferroptosis , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/metabolismo , Aspartato Aminotransferasa Citoplasmática/metabolismo , Aspartato Aminotransferasa Citoplasmática/uso terapéutico , Neoplasias Hepáticas/metabolismo , Factor 2 Relacionado con NF-E2/genética , Glutamina/farmacología , Glutamina/metabolismo , Línea Celular Tumoral
5.
Front Plant Sci ; 13: 965723, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36247627

RESUMEN

The study aimed to investigate the effect and mechanism of eugenol treatment on fresh-peeled Chinese water chestnuts (CWCs). The results found that eugenol treatment maintained the appearance of fresh-peeled CWCs, accompanied by higher L* value, total solids and O2 contents, as well as lower browning degree, weight loss rate, CO2 content, a* and b* values. In addition, eugenol treatment significantly reduced the activities of peroxidase, phenylalanine ammonia-lyase, and polyphenol oxidase, as well as the total content of soluble quinone in fresh-peeled CWCs. Meanwhile, fresh-peeled CWCs treated with eugenol showed markedly lower content of total flavonoids, which may be related to yellowing. Furthermore, eugenol treatment suppressed the rates of O2·- and OH·- production as well as the contents of H2O2 and malondialdehyde in fresh-peeled CWCs. During the storage, eugenol treatment not only increased the activities of catalase, superoxide dismutase, ascorbate peroxidase and glutathione reductase as well as the DPPH free radical scavenging rate, but also increased the total phenolics, ascorbic acid and glutathione contents. In summary, eugenol treatment delayed the surface discoloration of fresh-peeled CWCs by improving the antioxidant capacity, inhibiting the phenolic compound metabolism and scavenging ROS, thus effectively maintaining the quality of fresh-peeled CWCs while extending their shelf life.

6.
Int J Med Sci ; 19(8): 1235-1240, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35928716

RESUMEN

Spontaneous intracerebral hemorrhage (ICH) is associated with high mortality and disability rates. The microglia-induced inflammatory response is a critical factor determining brain tissue damage after ICH. Raddeanin A (RA) is a natural triterpenoid compound with anti-inflammatory effects, although its effects on ICH and the underlying molecular mechanism have not been elucidated. In this study, we found that RA reduced the volume of cerebral hematoma and cerebral edema, attenuated neuronal apoptosis and improved the behavioral indices in a murine model of acute cerebral hemorrhage. Mechanistically, RA downregulated the TLR4-mediated pro-inflammatory effectors, reduced infiltration of microglia in peri-intracerebral hemorrhage and inhibited apoptosis of neurons co-cultured with activated microglia. In conclusion, RA can alleviate ICH-related tissue damage and promote the recovery of neuronal function by suppressing microglia-induced inflammation and apoptosis.


Asunto(s)
Edema Encefálico , Receptor Toll-Like 4 , Animales , Edema Encefálico/complicaciones , Edema Encefálico/etiología , Hemorragia Cerebral/complicaciones , Hemorragia Cerebral/tratamiento farmacológico , Ratones , Microglía , Saponinas
7.
Sci Rep ; 11(1): 8742, 2021 04 22.
Artículo en Inglés | MEDLINE | ID: mdl-33888857

RESUMEN

Deep-brain stimulation (DBS) is an effective treatment for patients with Meige syndrome. The globus pallidus interna (GPi) and the subthalamic nucleus (STN) are accepted targets for this treatment. We compared 12-month outcomes for patients who had undergone bilateral stimulation of the GPi or STN. Forty-two Asian patients with primary Meige syndrome who underwent GPi or STN neurostimulation were recruited between September 2017 and September 2019 at the Department of Neurosurgery, Peking University People's Hospital. The primary outcome was the change in motor function, including the Burke-Fahn-Marsden Dystonia Rating Scale movement (BFMDRS-M) and disability subscale (BFMDRS-D) at 3 days before DBS (baseline) surgery and 1, 3, 6, and 12 months after surgery. Secondary outcomes included health-related quality of life, sleep quality status, depression severity, and anxiety severity at 3 days before and 12 months after DBS surgery. Adverse events during the 12 months were also recorded. Changes in BFMDRS-M and BFMDRS-D scores at 1, 3, 6, and 12 months with DBS and without medication did not significantly differ based on the stimulation target. There were also no significant differences in the changes in health-related quality of life (36-Item Short-Form General Health Survey) and sleep quality status (Pittsburgh Sleep Quality Index) at 12 months. However, there were larger improvements in the STN than the GPi group in mean score changes on the 17-item Hamilton depression rating scale (- 3.38 vs. - 0.33 points; P = 0.014) and 14-item Hamilton anxiety rating scale (- 3.43 vs. - 0.19 points; P < 0.001). There were no significant between-group differences in the frequency or type of serious adverse events. Patients with Meige syndrome had similar improvements in motor function, quality of life and sleep after either pallidal or subthalamic stimulation. Depression and anxiety factors may reasonably be included during the selection of DBS targets for Meige syndrome.


Asunto(s)
Estimulación Encefálica Profunda , Globo Pálido/fisiopatología , Núcleo Subtalámico/fisiopatología , Anciano , Femenino , Humanos , Masculino , Síndrome de Meige/fisiopatología , Persona de Mediana Edad , Estudios Retrospectivos
8.
Clin Neurol Neurosurg ; 175: 57-60, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30384117

RESUMEN

OBJECTIVES: The extent of resection is an independent predictor of prognosis in patients with glioblastomas. Although fluorescein sodium may enhance intraoperative visualization of tumor margin and increase the extent of glioblastoma, the dose related anaphylactic reaction is still a major concern. In the present study, we used allergy skin testing to exclude the patients susceptible to anaphylaxis preoperatively, and then investigated the feasibility of low-dose fluorescein sodium to guide glioblastoma resection intraoperatively, thereby to improve the safety of fluorescein-guided glioma resection. PATIENTS AND METHODS: Patients with suspected glioblastoma based on brain MRI were subjected to allergy skin intradermal tests for fluorescein sodium preoperatively. Only those with negative allergy skin tests received intravenous injection of low dose fluorescein sodium (1-2 mg/kg) during microsurgical tumor resection under dedicated Yellow 560 filter. The degree of fluorescent staining was documented and the extent of resection was evaluated by MRI scan. RESULTS: One patient with positive allergy skin test was excluded from fluorescein sodium administration and no anaphylactic reaction was found during fluorescein sodium guided surgery in the patients who were negative for allergy skin tests. The low dose fluorescein sodium (1-2 mg/kg) could provide enough visualization of tumors with sufficient discrimination from surrounding normal brain tissue and improve the resection extent of glioblastoma. CONCLUSION: Preoperative allergy skin test is a useful method to exclude the patients susceptible to anaphylaxis, together with intraoperative low dose fluorescein sodium administration, may facilitate glioblastoma resection by fluorescence guidance while avoid safety concern of dose-related anaphylaxis.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/cirugía , Fluoresceína/administración & dosificación , Colorantes Fluorescentes/administración & dosificación , Glioblastoma/diagnóstico por imagen , Glioblastoma/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Anafilaxia/inducido químicamente , Anafilaxia/prevención & control , Estudios de Cohortes , Estudios de Factibilidad , Femenino , Fluoresceína/efectos adversos , Colorantes Fluorescentes/efectos adversos , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Cuidados Preoperatorios/métodos , Estudios Retrospectivos , Pruebas Cutáneas/métodos
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