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1.
Zhongguo Yi Liao Qi Xie Za Zhi ; 48(2): 138-143, 2024 Mar 30.
Artículo en Chino | MEDLINE | ID: mdl-38605611

RESUMEN

Adrenal vein sampling is required for the staging diagnosis of primary aldosteronism, and the frames in which the adrenal veins are presented are called key frames. Currently, the selection of key frames relies on the doctor's visual judgement which is time-consuming and laborious. This study proposes a key frame recognition algorithm based on deep learning. Firstly, wavelet denoising and multi-scale vessel-enhanced filtering are used to preserve the morphological features of the adrenal veins. Furthermore, by incorporating the self-attention mechanism, an improved recognition model called ResNet50-SA is obtained. Compared with commonly used transfer learning, the new model achieves 97.11% in accuracy, precision, recall, F1, and AUC, which is superior to other models and can help clinicians quickly identify key frames in adrenal veins.


Asunto(s)
Aprendizaje Profundo , Rayos X , Radiografía
2.
Mar Pollut Bull ; 200: 116069, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38335629

RESUMEN

With the rapid economic development of coastal cities, the discharge of substantial amounts of heavy metal pollutants poses a serious hazard to mangroves; however, the potential sources of heavy metals and the resulting health risks are not fully understood. In this study, we analyzed the contents, sources, and ecological and health risks of heavy metal contamination in mangrove sediments from the northern margin of China. The accumulation of heavy metals in mangroves was primarily driven by five potential sources, namely agricultural (33.5 %), natural sources (21.3 %), industrial (19.1 %), aquaculture (14.3 %), and traffic (11.8 %). The assessment of health risks using a probabilistic approach demonstrated that noncarcinogenic risks were within acceptable limits for all populations. It was worth noting that both noncarcinogenic and carcinogenic risks were greater in children than in adults. Analysis of source-oriented health risks revealed that agricultural sources and As and Cd were priority sources and elements of pollution requiring attention.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Adulto , Niño , Humanos , Monitoreo del Ambiente , Suelo , Contaminantes del Suelo/análisis , Medición de Riesgo , China , Metales Pesados/análisis , Cadmio
3.
Sci Total Environ ; 920: 171028, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38378067

RESUMEN

Mangroves are the cradle of coastal water biodiversity and are susceptible to heavy metal pollution. However, the trophic transfer mechanism of heavy metals in the mangrove food web and the resulting human health risks are not fully understood. Heavy metal concentration (Cr, Ni, Cu, Zn, As, Cd, Pb, V, Co) and stable isotope ratios of carbon and nitrogen (δ13C and δ15N) were evaluated in sediments and particulate organic matter, litter, and aquatic organisms (plankton, arthropods, mollusks, omnivorous fish, and carnivorous fish) from the Yanpu Bay mangroves. The results revealed that heavy metals exhibited different trophic transfer patterns. As and Hg were efficiently biomagnified, with trophic magnification factors of 1.17 and 1.42, respectively; while Cr, Ni, Cu, Cd, Pb, V, and Co were efficiently biodiluted. Zn exhibited a trophic magnification factor > 1 and was not significantly correlated with δ15N (p > 0.05), suggesting no biomagnification or biodilution. The heavy metals in the important fishery species (omnivorous fish and carnivorous fish) were below the permissible limits, except for Zn in Ophichthus apicalis. The assessment of probabilistic health risks revealed that fish consumption in adults and children posed an acceptable risk (total target hazard quotient <1).


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , Animales , Niño , Humanos , Cadena Alimentaria , Bahías , Cadmio , Plomo , Monitoreo del Ambiente/métodos , Metales Pesados/análisis , Peces , Medición de Riesgo , China , Contaminantes Químicos del Agua/análisis
4.
J Colloid Interface Sci ; 656: 320-331, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-37995402

RESUMEN

Ferroptosis-mediated tumor treatment is constrained by the absence of single-component, activatable multifunctional inducers. Given this, a topological synthesis strategy is employed to develop an efficient bismuth-based semiconductor nano-photocatalyst (Bi2O3:S) for tumor ferroptosis therapy. Photo-excited electrons can participate in the reduction reaction to produce harmful reactive oxygen species (ROS) when exposed to near-infrared light. Meanwhile, photo-excited holes can contribute to the oxidation reaction to utilize extra glutathione (GSH) in tumors. In the acidic tumor microenvironment, bismuth ions generated from Bi2O3:S may further cooperate with GSH to amplify oxidative stress damage and achieve biodegradation. Both promote ferroptosis by downregulating glutathione peroxidase 4 (GPX4) expression. Besides, sulfur doping optimizes its near-infrared light-induced photothermal conversion efficiency, benefiting its therapeutic effect. Thus, bismuth ions and holes synergistically drive photo-activable ferroptosis in this nanoplatform, opening up new avenues for tumor therapy.


Asunto(s)
Ferroptosis , Neoplasias , Fotoquimioterapia , Humanos , Bismuto , Glutatión , Especies Reactivas de Oxígeno , Iones , Neoplasias/terapia , Línea Celular Tumoral , Fototerapia , Microambiente Tumoral
5.
Mar Pollut Bull ; 177: 113491, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35287010

RESUMEN

Understanding the effects of habitat heterogeneity on the functioning of macrobenthic communities is essential to the conservation of biodiversity in coastal ecosystems. However, the effects of habitat heterogeneity on the functional trait composition and diversity of seagrass bed macrobenthos are as scarce. In the present study, functional diversity indices (i.e., functional dispersion, functional richness, and Rao's quadratic entropy), RLQ analysis, and fourth-corner analysis indicated that macrobenthic functional trait composition and diversity differ among seagrass bed microhabitats (interior, edge, and bare sediment). More specifically, functional traits were more evenly distributed in the seagrass bed interior and edge habitats, when compared to bare sediment, and functional diversity was significantly higher (p < 0.01). Functional trait distributions were influenced by environmental parameters (e.g., total organic carbon, organic matter, and grain size). Suspension-feeding and burrowing bivalves preferentially inhabited bare sediment with high sand content and low TOC, whereas herbivorous, small, and sensitive species mainly inhabited muddy sediments with higher organic supply.


Asunto(s)
Biodiversidad , Ecosistema , Sedimentos Geológicos , Fenotipo , Arena
6.
Acta Biomater ; 129: 280-292, 2021 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-34033970

RESUMEN

Various physiological characteristics of the tumor microenvironment (TME), such as hypoxia, overexpression of glutathione (GSH) and hydrogen peroxide (H2O2), and mild acidity, can severely reduce the efficacy of many cancer therapies. Altering the redox balance of the TME and increasing oxidative stress can accordingly enhance the efficacy of tumor therapy. Herein, we developed a bismuth-based Cu2+-doped BiOCl nanotherapeutic platform, BCHN, able to self-supply H2O2 for TME-regulated chemodynamic therapy (CDT) combined with sensitized radiotherapy (RT). BCHN released H2O2 and consumed GSH to degrade the composite in the slightly acidic TME, and generated hydroxyl radicals (•OH) via a Fenton-like reaction catalyzed by copper ions, to achieve oxidative stress-enhanced CDT. The Fenton-like reaction also catalyzed H2O2 to produce O2 to relieve tumor hypoxia, and combined with the X-ray-blocking property of bismuth to realize TME-enhanced radiotherapy. Synergistic CDT/RT has previously been shown to effectively inhibit tumor cell proliferation and achieve effective tumor control. The current results demonstrated a highly efficient multifunctional bio-degradable nanoplatform for oncotherapy. STATEMENT OF SIGNIFICANCE: Tumor microenvironment-modulated synergy of radiotherapy and chemodynamic therapy is conducive to rapid tumor ablation. Based on this principle, we fabricated a biodegradable BiOCl-based nanocomposite, BCHN. By supplying H2O2, a Fenton-like reaction generated •OH and O2 catalyzed by copper ions, and consumed glutathione to biodegrade the composite. Overall, these actions increased tumor oxidative stress and realized the synergistic anti-tumor actions of chemodynamic therapy combined with bismuth-based sensitization radiotherapy. This strategy thus provides a unique approach to oncology therapy.


Asunto(s)
Peróxido de Hidrógeno , Microambiente Tumoral , Línea Celular Tumoral , Humanos , Hipoxia , Estrés Oxidativo
7.
Acta Biomater ; 119: 323-336, 2021 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-33122146

RESUMEN

Phototherapy, including photodynamic and photothermal therapies, is a non-invasive photo-triggered tumor treatment. Combination therapy and new synergistic therapeutic reagents may hold promise for improving these treatments. Herein, we report an amphiphilic iridium-based photosensitizer (C14-IP2000) loaded with a hydrophobic photo-thermal drug (ZnPc) to form nano-micelles (ZNPs) for dual-light triggered tumor phototherapy. The C14-IP2000 was contained within ZNPs consisting of an iridium complex core decorated with hydrophilic polyethylene glycol chains to extend the time in blood circulation, and two hydrophobic carbon chains to enhance the loading capacity and the hydrophobic interaction with the loaded reagent. The designed ZNPs showed effective blood circulation, passive tumor targeting ability, remarkable photodynamic conversion ability, and good photothermal conversion capability, and therefore may be used for combined tumor ablation. Our results demonstrated that the amphipathic bionic structure of ZNPs not only enables self-assembled reagent fabrication with prolonged circulation time and favorable metabolic characteristics for tumor combination therapy, but also provides a nanostructure strategy for the modification of functionalized reagents.


Asunto(s)
Hipertermia Inducida , Nanopartículas , Fotoquimioterapia , Línea Celular Tumoral , Humanos , Hipertermia , Micelas , Fototerapia
8.
ACS Appl Mater Interfaces ; 12(52): 57768-57781, 2020 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-33326213

RESUMEN

Solid tumors inevitably develop radioresistance due to low oxygen partial pressure in the tumor microenvironment. Despite numerous attempts, there are still few effective ways to avoid the hypoxia-induced poor radiotherapeutic effect. To overcome this problem, platinum (Pt) nanodots were fabricated into a mesoporous bismuth (Bi)-based nanomaterial to construct a biodegradable nanocomposite BiPt-folic acid-modified amphiphilic polyethylene glycol (PFA). BiPt-PFA could act as a radiosensitizer to enhance the absorption of X-rays at the tumor site and simultaneously trigger response behaviors related to the tumor microenvironment due to the enrichment of materials in the tumor area. During this process, the Bi-based component consumed glutathione via coordination, thus altering the oxidative stress balance, while Pt nanoparticles catalyzed the decomposition of hydrogen peroxide to generate oxygen, thereby relieving tumor hypoxia. Both Pt and Bi thus co-modulated the tumor microenvironment to improve the radiotherapeutic effect. In addition, Pt dots in BiPt-PFA had strong near-infrared absorption ability and created an intensive photothermal therapeutic effect. Modulation of the tumor microenvironment could thus improve the therapeutic effect in hypoxic tumors by a combination of photothermal therapy and enhanced radiotherapy. BiPt-PFA, as a biodegradable nanocomposite, may thus modulate the tumor microenvironment to enhance the hypoxic tumor therapeutic effect by thermoradiotherapy.


Asunto(s)
Bismuto/química , Nanocompuestos/química , Fármacos Sensibilizantes a Radiaciones/química , Hipoxia Tumoral/efectos de los fármacos , Microambiente Tumoral/efectos de los fármacos , Animales , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Humanos , Hipertermia Inducida , Nanopartículas del Metal/química , Ratones , Platino (Metal)/química , Polietilenglicoles/química , Porosidad , Fármacos Sensibilizantes a Radiaciones/farmacología , Seguridad , Solubilidad , Hipoxia Tumoral/efectos de la radiación , Microambiente Tumoral/efectos de la radiación , Agua/química
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