RESUMO
Devising carbon dots with long wavelength emission (red light or near infrared), high selectivity and good bio-compatibility is critical in fluorescence detection and imaging, but achieving this goal remains a great challenge. Herein, near-infrared emissive carbon dots (NIR-CDs) with obvious emission characteristic of 653 nm were synthesized through hydrothermally treatment of toluidine bule and gallic acid. Noticeably, the NIR-CDs exhibited excellent selectivity and sensitivity to hypochlorite (ClO-), and the limit of detection is as low as 42.7 nM. The selective recognition reaction between ClO- and the surface functional groups of NIR-CDs inhibits the fluorescence from NIR-CDs. The quenching mechanism was confirmed by fluorescence lifetime decays, FT-IR spectroscopy and UV-vis absorption spectra. More remarkably, the NIR-CDs have rich hydrophilic groups showed lower cytotoxicity, excellent bio-compatibility and specific cell membrane localization ability. The established spectrofluorometric method based on NIR-CDs has been used to determination of ClO- level in tap water sample, the recoveries were 97.7 %-103.3 %. In addition, the NIR-CDs also has been successfully applied for the imaging of cell membrane. The study provides a novel idea for developing NIR ClO- probe as well as cell membrane localization probe based on CDs, which present bright prospects in real water samples monitoring and cell membrane imaging.
Assuntos
Carbono , Membrana Celular , Ácido Hipocloroso , Pontos Quânticos , Ácido Hipocloroso/análise , Pontos Quânticos/química , Carbono/química , Humanos , Membrana Celular/química , Espectrometria de Fluorescência , Limite de Detecção , Espectroscopia de Infravermelho com Transformada de Fourier , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Células HeLaRESUMO
Treatment of triple-negative breast cancer (TNBC) has long been a medical challenge because of the lack of effective therapeutic targets. Targeting lipid, carbohydrate, and nucleotide metabolism pathways has recently been proven as a promising option in view of three heterogeneous metabolic-pathway-based TNBC subtypes. Here, we present a multimodal anticancer platinum(II) complex, named Pt(II)caffeine, with a novel mode of action involving simultaneous mitochondrial damage, inhibition of lipid, carbohydrate, and nucleotide metabolic pathways, and promotion of autophagy. All these biological processes eventually result in a strong suppression of TNBC MDA-MB-231 cell proliferation both in vitro and in vivo. The results indicate that Pt(II)caffeine, influencing cellular metabolism at multiple levels, is a metallodrug with increased potential to overcome the metabolic heterogeneity of TNBC.
Assuntos
Platina , Neoplasias de Mama Triplo Negativas , Humanos , Platina/farmacologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/metabolismo , Cafeína/uso terapêutico , Linhagem Celular Tumoral , Carboidratos/farmacologia , Nucleotídeos/farmacologia , Lipídeos/farmacologia , Proliferação de Células , ApoptoseRESUMO
The effect of sediment and residual fish feed on aquaculture water bodies has gained increasing attention to alleviate the eutrophication and heavy metals enrichment induced by aquaculture. Thus, this study intended to reveal the possible interactions among nutrients, heavy metals, and Chlorella vulgaris (C. vulgaris) in aquaculture water bodies containing fish feed and sediment. The analyses showed that consistent with the composition of heavy metals in fish feed, manganese (Mn) and zinc (Zn) accounted for the highest proportions (68-78%) of heavy metals in sediment. Meanwhile, sediment in the centre of aquaculture water bodies (S2) contained more heavy metals than those in the perimeter (S1), but the released concentrations and rates (Rrelease) of heavy metals from S1 were higher than those from S2. Moreover, the biomass, growth rate, specific growth rate, and nitrogen and carbon fixation rate of C. vulgaris increased with adding fish feed, whereas superoxide dismutase (SOD) and malondialdehyde (MDA) decreased. In addition, with C. vulgaris, influenced by the release process from sediment and the uptake by C. vulgaris, the concentration and Rrelease of Mn, Pb, Cu, Mn, Cr and Cd from sediments coexisting with fish feed in water first increased and then decreased in general. The C. vulgaris biomass was significantly negatively related to Mn, Pb, Cu, Ni, Cr, and Cd and PO43-P (P < 0.05), which was caused by the uptake of C. vulgaris and indicated that C. vulgaris biomass is easily affected by these factors. Accordingly, the input of residual fish feed and sediment should be controlled.
Assuntos
Chlorella vulgaris , Metais Pesados , Poluentes Químicos da Água , Animais , Sedimentos Geológicos/análise , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Ecossistema , Cádmio/análise , Chumbo/análise , Metais Pesados/análise , Aquicultura , Peixes , Água/análise , Manganês/análise , Nutrientes , Medição de RiscoRESUMO
To achieve its carbon neutrality goal, China has invested broadly in energy infrastructure and the emerging integrated energy stations (IESs) projects will bring enormous opportunities. Accurate carbon emission accounting for IESs is challenging in view of the complexity of the manufacturing process and uncertainty in construction and operation processes. To overcome these challenges, this paper develops a novel quantitative carbon footprint analysis model for IESs from a lifecycle perspective, with production and materialization, construction, operation and maintenance, and disposal and recycling phases considered. The method is applied on a 110 kV wind power IES project in China, to analyze and calculate lifecycle carbon emissions, identify the key influence factors of carbon footprints and provide suggestions for carbon reduction. The findings can identify key influence factors and provide suggestions for carbon reduction for the development of IES projects.
Assuntos
Pegada de Carbono , Carbono , Animais , China , Carbono/análise , Estágios do Ciclo de Vida , Dióxido de CarbonoRESUMO
The hedgehog (Hh) pathway is tightly related with the formation, metastasis and recurrence of various cancers, which makes it a perfect anticancer target. Smoothened (SMO) is one of its key members. Three drugs targeting the Hh pathway have been successfully used in clinic, and they are all known as SMO inhibitors. However, serious drug resistant problem has limited their clinical application. The interaction of oncogenic ERK pathway with the Hh pathway in multiple ways has been proved as one of the main factors that result in drug resistance. Dual inhibition of the Hh and ERK pathways has displayed synergistic suppression to cancer cells overexpressing both pathways. Herein, we designed and synthesized a series of novel 4-aminopiperidine derivatives as SMO/ERK dual inhibitors, and evaluated their biological activities. The results showed that compounds I-13 displayed strong inhibitory activities towards both SMO and ERK, and it also exhibited significant cytotoxicity against human cholangiocarcinoma RBE cells which overexpress both the Hh and ERK pathways. All the results indicate that compound I-13 is a promising anticancer candidate as a SMO/ERK dual inhibitor.
Assuntos
Proteínas Hedgehog , Neoplasias , Humanos , Proteínas Hedgehog/metabolismo , Transdução de Sinais , Receptor Smoothened/metabolismo , Inibidores de Proteínas Quinases/farmacologiaRESUMO
Models that accurately estimate maximum crop biomass to obtain a reliable forecast of yield are useful in crop improvement programs and aiding establishment of government policies, including those addressing issues of food security. Here, we present a new sigmoidal growth model (NSG) and compare its performance with the beta sigmoidal growth model (BSG) for capturing the growth trajectories of eight crop species. Results indicated that both the NSG and the BSG fitted all the growth datasets well (R2 > 0.98). However, the NSG performed better than the BSG based on the calculated value of Akaike's information criterion (AIC). The NSG provided a consistent estimate for when maximum biomass occurred; this suggests that the parameters of the BSG may have less biological importance as compared to those in the NSG. In summary, the new sigmoidal growth model is superior to the beta sigmoidal growth model, which can be applied to capture the growth trajectory of various plant species regardless of the initial biomass values at the beginning of a growth period. Findings of this study will be helpful to understand the growth trajectory of different plant species regardless of their initial biomass values at the beginning of a growth period.