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1.
Sci Total Environ ; 912: 169154, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38065501

RESUMEN

Submerged plants constitute a vital component of shallow lake ecosystems, where water depth and sediment nitrogen­phosphorus content are two key factors influencing their growth. This study focuses on Vallisneria natans and investigates the morphological and physiological changes of V. natans under the interaction of three water depth gradients and two different sediment nutrient levels. It explores the mechanisms through which varying sediment nutrient conditions under different water depths affect the growth of V. natans. The results indicate that both independent and interactive effects of water depth and sediment nutrient status significantly impact the morphology, antioxidant enzyme activity, and photosynthetic pigment content of V. natans, with water depth having a greater influence. To adapt to increased water depth-induced light stress, V. natans responds morphologically by increasing leaf length, leaf width, and decreasing maximum root length. Physiologically, it enhances its antioxidant regulation capacity and photosynthetic efficiency by increasing antioxidant enzyme activity, root vitality, and photosynthetic pigment content to counter weak light stress. However, these adaptations are insufficient to cope with excessively deep waters (200 cm). Sediment nutrient levels primarily control the growth of V. natans by affecting its root system. When sediment nitrogen and phosphorus content is lower, V. natans exhibits greater total root volume and surface area to enhance nutrient absorption efficiency. Water depth not only directly influences the growth of submerged plants but may also impact the migration and transformation of phosphorus in sediments, further exacerbating its effects on the growth of these plants, thus accelerating the regime shift of shallow lakes. Therefore, this study reveals V. natans' response strategies to varying water depths and sediment nutrient levels, determining suitable water levels and sediment nutrient conditions for its growth. These research findings provide a scientific basis for water level management and ecological restoration of submerged aquatic plants in shallow lakes.


Asunto(s)
Ecosistema , Hydrocharitaceae , Agua , Antioxidantes , Hydrocharitaceae/fisiología , Lagos , Nitrógeno , Fósforo , Nutrientes
2.
ACS Appl Mater Interfaces ; 12(5): 5520-5530, 2020 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-31891473

RESUMEN

Radiotherapy (RT) is one of the most widely used cancer treatments in the clinical setting, while hypoxia-associated resistance often occurs. Herein, a PEGylated TaOx-based oxygen-carrying nanoplatform was constructed for triple sensitizing tumor radiotherapy. The high-Z element based hollow mesoporous TaOx nanospheres were prepared following the in situ growth of ultrasmall CuS nanocrystals and then packaged with O2-saturated perfluoropentane (PFP). NIR laser-triggered mild hyperthermia would lead to the increase of intratumoral blood flow, together with the release of O2, the radiotherapeutic efficiency would be enhanced. Alternatively, radiant energy would be deposited inside the tumor by the Ta element, therefore triple sensitization of radiotherapy could be achieved. The in vivo studies showed that the as-prepared nanospheres could achieve almost total inhibition of tumor growth without obvious side effects, which provides new possibilities for multisensitizing tumor radiotherapy.


Asunto(s)
Materiales Biocompatibles/uso terapéutico , Nanosferas/química , Neoplasias/terapia , Óxidos/química , Tantalio/química , Animales , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cobre/química , Femenino , Fluorocarburos/química , Humanos , Hipertermia Inducida , Rayos Infrarrojos/uso terapéutico , Ratones , Ratones Endogámicos BALB C , Nanosferas/toxicidad , Neoplasias/patología , Neoplasias/radioterapia , Oxígeno/química , Porosidad , Especies Reactivas de Oxígeno/metabolismo
3.
Molecules ; 23(6)2018 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-29882878

RESUMEN

An efficient and practical approach towards bifunctional phosphorus phenols has been developed through a reaction of diphenylphosphine oxide and the o-quinone methides in situ generated from 2-tosylalkyl phenols under basic conditions. This protocol features simple experimental procedures under mild conditions and is easily scaled up. With this method, a variety of diarylmethyl phosphine oxides can be produced with up to 92% yield.


Asunto(s)
Indolquinonas/química , Fenoles/síntesis química , Fosfinas/química , Fósforo/química , Espectroscopía de Resonancia Magnética con Carbono-13 , Concentración de Iones de Hidrógeno , Fenoles/química , Espectroscopía de Protones por Resonancia Magnética , Espectrometría de Masa por Ionización de Electrospray
4.
BMC Complement Altern Med ; 17(1): 455, 2017 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-28886741

RESUMEN

BACKGROUND: Nonalcoholic steatohepatitis (NASH) is a progressive form of nonalcoholic fatty liver disease, for which there is currently no safe and effective drug for therapy. In this study, we explored the effects of taurine, tea polyphenols (TPs), or a combination thereof, on NASH rats. METHODS: Rats were divided into a normal group, a high-fat diet induced model group and a treatment group (including taurine, TPs, or taurine + TPs treatment for 8 weeks). Twelve weeks later, all rats were sacrificed, and serum transaminase, lipid and lipopolysaccharide levels and hepatic oxidative stress levels were determined. Histological changes were evaluated. RESULTS: In NASH rats, hepatocyte damage, lipid disturbance, oxidative stress and elevated lipopolysaccharide levels were confirmed. Taurine treatment alleviated hepatocyte damage and oxidative stress. TPs treatment improved lipid metabolism and increased hepatic antioxidant activity. The therapeutic effects of taurine + TPs treatment on hepatocyte damage, lipid disturbance, and oxidative stress were superior to those of taurine and TPs treatment, respectively. Taurine, TPs and their combination all decreased serum lipopolysaccharide levels in NASH rats, but the combination of the compounds caused these levels to decrease more significantly than taurine or TPs treatment alone. CONCLUSION: Taurine combined with TPs treatment could relieve NASH by alleviating hepatocyte damage, decreasing oxidative stress and improving lipid metabolism and gut flora disturbance partly. Taurine and TPs combination may act as a new effective medicine for treating NASH patients.


Asunto(s)
Antioxidantes/farmacología , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Estrés Oxidativo/efectos de los fármacos , Polifenoles/farmacología , Taurina/farmacología , , Animales , Hígado/efectos de los fármacos , Masculino , Ratas , Ratas Sprague-Dawley
5.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 25(7): 643-5, 2005 Jul.
Artículo en Chino | MEDLINE | ID: mdl-16089146

RESUMEN

OBJECTIVE: To explore the effect of qingfei oral liquid (QOL) contained serum on protein expression of transforming growth factor-beta1 (TGF-beta1) and platelet derived growth factor-BB (PDGF-BB) of adenovirus type 3I, 7b induced human embryonic lung fibroblast cells. METHODS: The cells were divided into 5 groups, the normal cells group (NCG), the virus control group (VCG), the blank serum group (BSG), the ribavirin group (RVG) and the QOL contained serum group (QSG). All the cells except those in the NCG were challenged by adenovirus type 3I, 7b and treated with correspondent medicine. The contents of TGF-beta1 and PDGF-BB in the supernatant of cell culture were monitored by ELISA and compared among groups. RESULTS: Contents of TGF-beta1 and PDGF-BB in VCG were significantly higher, while those in QSG were significantly lower than those in VCG (P < 0.01). CONCLUSION: Adenovirus infection can increase the protein expression of TGF-beta1 and PDGF-BB of human embryonic lung fibroblast cells. QOL can decrease the protein expression of these cytokines, which maybe one of the mechanisms of its antiviral effect.


Asunto(s)
Adenovirus Humanos , Medicamentos Herbarios Chinos/farmacología , Fibroblastos/virología , Factor de Crecimiento Derivado de Plaquetas/biosíntesis , Factor de Crecimiento Transformador beta/biosíntesis , Adenovirus Humanos/clasificación , Adenovirus Humanos/efectos de los fármacos , Adenovirus Humanos/crecimiento & desarrollo , Animales , Becaplermina , Células Cultivadas , Embrión de Mamíferos , Femenino , Fibroblastos/citología , Humanos , Masculino , Proteínas Proto-Oncogénicas c-sis , Conejos , Factor de Crecimiento Transformador beta1
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