RESUMEN
Squamous cell carcinoma antigen (SCCA) is one of the common squamous cell carcinomas (SCC) in women, which usually works as a tumor biomarker for cervical cancer in diagnostic applications. Herein, bimetallic PtCo highly branched nanocrystals (PtCo BNCs) acted as electrode substrates to construct sandwich-typed electrochemical immunosensor for ultrasensitive detection of SCCA, by using dendritic mesoporous SiO2@AuPt nanoparticles (DM-SiO2@AuPt NPs) to adsorb electroactive thionine (Thi) as a signal label. The PtCo BNCs enlarged the loading of the primary antibody (Ab1), showing effective improvement in conductivity and sensitivity. The DM-SiO2 had abundant pores to incorporate more Thi, on which the decorated AuPt NPs created a great number of active sites to immobilize the secondary antibodies (Ab2), thereby obviously amplifying the detection signals. The prepared sensor exhibited a broader linear range (0.001-120 ng mL-1) and a lower detection limit (0.33 pg mL-1, S/N = 3), combined with high reproducibility, a low relative standard deviation (below 2.5%) and acceptable recovery (from 98.5 to 110.0%) even in diluted human serum samples. This research provides a substantial platform for clinical diagnosis of SCCA in practice.
Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Antígenos de Neoplasias , Biomarcadores de Tumor , Técnicas Electroquímicas , Femenino , Oro/química , Humanos , Inmunoensayo , Límite de Detección , Nanopartículas del Metal/química , Reproducibilidad de los Resultados , Serpinas , Dióxido de Silicio/químicaRESUMEN
Human epididymis protein 4 (HE4) is a vital biomarker for early diagnosis of epithelial ovarian cancer (EOC). Herein, a new label-free biosensor was developed using K3[Fe(CN)6] as the electrochemical probe for ultrasensitive immunoassay of HE4 based on PtNi nanocubes assemblies (NCAs) as efficient biosensing interfaces. The PtNi NCAs were synthesized by a simple solvothermal approach, where N-hexadecyltrimethylammonium chloride (HTAC) and 2,2'-bis(4,5-dimethylimidazole) (BDMM) behaved as co-structuring directors. Under the optimal conditions, the obtained HE4 immunosensor displayed a wide detection range from 0.001 to 100 ng mL-1 and a low detection limit (0.11 pg mL-1, S/N = 3). As a result, the current sensing platform would serve as a useful reference for detecting cancer biomarkers in the clinical assay and diagnosis.
Asunto(s)
Técnicas Biosensibles , Neoplasias Ováricas , Femenino , Humanos , Inmunoensayo , Detección Precoz del Cáncer , Neoplasias Ováricas/diagnóstico , Biomarcadores de TumorRESUMEN
A signal-on sandwich-like electrochemical immunosensor was built for determination of cytokeratin 19 fragments 21-1 (CYFRA 21-1) in non-small cell lung cancer (NSCLC) by confining electroactive dye (e.g., methylene blue, MB) as a probe for amplifying signals. Specifically, core-shell gold@rhodium dendritic nanocrystals (Au@Rh DNCs) behaved as a substrate for primary antibody and accelerate interfacial electron transfer. Besides, hollow carbon spheres (HCSs) were subsequently modified with polydopamine (PDA) and PtPd nanoparticles for sequential integration of the secondary antibody and confinement of MB as a label, termed as MB/PtPd/PDA/HCSs for clarity. The built sensors showed a broad linear range (100 fg mL-1 ~ 100 ng mL-1) for detection of CYFRA 21-1 with an ultra-low detection limit (31.72 fg mL-1, S/N = 3), coupled with satisfactory performance in human serum samples. This work can be explored for assays of other proteins and provides some constructive insights for early and accurate diagnosis of NSCLC.
Asunto(s)
Técnicas Biosensibles , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Nanopartículas , Anticuerpos , Antígenos de Neoplasias , Carbono , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Humanos , Inmunoensayo , Indoles , Queratina-19 , Neoplasias Pulmonares/diagnóstico , PolímerosRESUMEN
The unresolved phylogenetic framework within the Selaginellaceae subfamily Gymnogynoideae (ca. 130 species) has hindered our comprehension of the diversification and evolution of Selaginellaceae, one of the most important lineages in land plant evolution. Here, based on plastid and nuclear data extracted from genomic sequencing of more than 90% species of all genera except two in Gymnogynoideae, a phylogenomic study focusing on the contentious relationships among the genera in Gymnogynoideae was conducted. Our major results included the following: (1) Only single-copy region (named NR) and only one ribosomal operon was firstly found in Afroselaginella among vascular plants, the plastome structure of Gymnogynoideae is diverse among the six genera, and the direct repeats (DR) type is inferred as the ancestral state in the subfamily; (2) The first strong evidence was found to support Afroselaginella as a sister to Megaloselaginella. Alternative placements of Ericetorum and Gymnogynum were detected, and their relationships were investigated by analyzing the variation of phylogenetic signals; and (3) The most likely genus-level relationships in Gymnogynoideae might be: ((Bryodesma, Lepidoselaginella), (((Megaloselaginella, Afroselaginella), Ericetorum), Gymnogynum)), which was supported by maximum likelihood phylogeny based on plastid datasets, maximum likelihood, and Bayesian inference based on SCG dataset and concatenated nuclear and plastid datasets and the highest proportion of phylogenetic signals of plastid genes.
RESUMEN
The fabrication of effective and stable electrocatalysts is crucial for practical applications of direct alcohol fuel cells (DAFCs). In this study, bimetallic PdCu nanostars (PdCu NSs) were fabricated by a Cu2+-modulated one-pot wet-chemical method, where cetyltrimethyl ammonium bromide (CTAB) worked as a structure-regulating reagent. The morphology, compositions, crystal structures and formation mechanism of the as-prepared PdCu NSs were investigated by a series of techniques. The unique architectures created abundant active sites, which resulted in a large electrochemical active surface area (9.5 m2 g-1). The PdCu NSs showed negative shifts in the onset potentials and large forward peak current densities by contrast with those of commercial Pd black for the catalytic ethylene glycol oxidation reaction (EGOR) and glycerol oxidation reaction (GOR). It revealed that the PdCu NSs outperformed Pd black in the similar surroundings. This work provides a constructive strategy for fabrication of high-efficiency electrocatalysts for alcohol fuel cells.
RESUMEN
BACKGROUND: Recent studies have demonstrated that mesenchymal stem cells (MSCs) can rescue injured target cells via mitochondrial transfer. However, it has not been fully understood how bone marrow-derived MSCs repair glomeruli in diabetic kidney disease (DKD). AIM: To explore the mitochondrial transfer involved in the rescue of injured glomerular endothelial cells (GECs) by MSCs, both in vitro and in vivo. METHODS: In vitro experiments were performed to investigate the effect of co-culture with MSCs on high glucose-induced GECs. The transfer of mitochondria was visua lized using fluorescent microscopy. GECs were freshly sorted and ultimately tested for apoptosis, viability, mRNA expression by real-time reverse transcri ptase-polymerase chain reaction, protein expression by western blot, and mitochondrial function. Moreover, streptozotocin-induced DKD rats were infused with MSCs, and renal function and oxidative stress were detected with an automatic biochemical analyzer and related-detection kits after 2 wk. Kidney histology was analyzed by hematoxylin and eosin, periodic acid-Schiff, and immunohistochemical staining. RESULTS: Fluorescence imaging confirmed that MSCs transferred mitochondria to injured GECs when co-cultured in vitro. We found that the apoptosis, proliferation, and mitochondrial function of injured GECs were improved following co-culture. Additionally, MSCs decreased pro-inflammatory cytokines [interleukin (IL)-6, IL-1ß, and tumor necrosis factor-α] and pro-apoptotic factors (caspase 3 and Bax). Mitochondrial transfer also enhanced the expression of superoxide dismutase 2, B cell lymphoma-2, glutathione peroxidase (GPx) 3, and mitofusin 2 and inhibited reactive oxygen species (ROS) and dynamin-related protein 1 expression. Furthermore, MSCs significantly ameliorated functional parameters (blood urea nitrogen and serum creatinine) and decreased the production of malondialdehyde, advanced glycation end products, and ROS, whereas they increased the levels of GPx and superoxide dismutase in vivo. In addition, significant reductions in the glomerular basement membrane and renal interstitial fibrosis were observed following MSC treatment. CONCLUSION: MSCs can rejuvenate damaged GECs via mitochondrial transfer. Additionally, the improvement of renal function and pathological changes in DKD by MSCs may be related to the mechanism of mitochondrial transfer.