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1.
Bioconjug Chem ; 35(3): 400-411, 2024 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-38366969

RESUMEN

Photodynamic therapy (PDT) is a cancer treatment strategy that utilizes photosensitizers to convert oxygen within tumors into reactive singlet oxygen (1O2) to lyse tumor cells. Nevertheless, pre-existing tumor hypoxia and oxygen consumption during PDT can lead to an insufficient oxygen supply, potentially reducing the photodynamic efficacy. In response to this issue, we have devised a pH-responsive amphiphilic triblock fluorinated polymer (PDP) using copper-mediated RDRP. This polymer, composed of poly(ethylene glycol) methyl ether acrylate, 2-(diethylamino)ethyl methacrylate, and (perfluorooctyl)ethyl acrylate, self-assembles in an aqueous environment. Oxygen, chlorine e6 (Ce6), and doxorubicin (DOX) can be codelivered efficiently by PDP. The incorporation of perfluorocarbon into the formulation enhances the oxygen-carrying capacity of PDP, consequently extending the lifetime of 1O2. This increased lifetime, in turn, amplifies the PDT effect and escalates the cellular cytotoxicity. Compared with PDT alone, PDP@Ce6-DOX-O2 NPs demonstrated significant inhibition of tumor growth. This study proposes a novel strategy for enhancing the efficacy of PDT.


Asunto(s)
Nanopartículas , Fotoquimioterapia , Porfirinas , Humanos , Polímeros de Fluorocarbono , Oxígeno , Línea Celular Tumoral , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico , Hipoxia/tratamiento farmacológico , Concentración de Iones de Hidrógeno
2.
Huan Jing Ke Xue ; 38(5): 2102-2110, 2017 May 08.
Artículo en Chino | MEDLINE | ID: mdl-29965119

RESUMEN

Soil respiration is an important process for carbon emission. A field study was conducted with four treatments including T (traditional tillage+straw mulching level 0 kg·hm-2), R (ridge tillage+straw mulching level 0 kg·hm-2), RS1 (ridge tillage+straw mulching level 3750 kg·hm-2), and RS2 (ridge tillage+straw mulching level 7500 kg·hm-2), so as to probe the effects of ridge tillage and straw mulching amount on soil respiration and soil organic carbon(SOC) and the relationships of soil respiration rate with soil temperature and water content (SWC) during the growth period of fava bean in the triple intercropping system of fava bean/maize/sweat pomato in dryland region of southwest China known as the purple hilly region. The changes of soil respiration rate were in accordance with crop growing, being firstly increased and then decreased during the whole growth period of fava bean, and there were significant differences in soil respiration rate among different treatments, which could be ranked as RS2[3.365 g·(m2·d)-1] > RS1[2.935 g·(m2·d)-1] > T[2.683 g·(m2·d)-1] > R[2.263 g·(m2·d)-1]. Ridge tillage reduced soil respiration in fava bean farmland, whereas straw mulching treatment increased it, whose variation trend was in accordance with that of straw mulching levels. There was a significant exponential relationship between soil respiration and soil temperature at 5 cm and 10 cm depth, and the exponential model at 10 cm produced better fitness than that at 5 cm. The temperature sensitivity (Q10) at 10 cm could be ranked as RS2 > RS1 > R > T, being 1.751,1.665,1.616, and 1.35, respectively. The combined exponential model indicated that soil temperature and water content (SWC) could jointly explain 68%(R), 79%(RS1) and 76%(RS2) of variation in soil respiration. This study results suggested that ridge tillage and straw mulching significantly increased SOC of 0-5 cm, 5-10 cm, 10-20 cm and 20-30 cm soil layers, and the increase of SOC was in accordance with that of straw mulching levels. The SOC was significantly increased in 5-10 cm and 10-20 cm soil layers, which could be ranked as RS2 > RS1 > R > T, and the increases in SOC at 5-10 cm were especially notable. The weighted average of particulate organic carbon (POC) at 0-30 cm was significantly increased, but the proportion of POC in SOC did not show significant influence.


Asunto(s)
Agricultura , Carbono/química , Suelo/química , China , Granjas , Triticum , Vicia faba
3.
Huan Jing Ke Xue ; 37(3): 1114-20, 2016 Mar 15.
Artículo en Chino | MEDLINE | ID: mdl-27337908

RESUMEN

Under the background of global warming, the farmland soil respiration has become the main way of agricultural carbon emissions. And green manure has great potential to curb greenhouse gas emissions and achieve energy conservation and emissions reduction. However, in purple soil region of Southwest, China, soil respiration under green manure remains unclear, especially in the winter and intercropping. Through the green manure ( Chinese milk vetch) intercropping with rape, therefore, we compared the effects of rape rhizosphere under straw mulching. The soil organic carbon and soil respiration were examined. The results showed, compared with straw mulching, root separation was the major influencing factors of soil organic carbon on rape rhizosphere. Soil organic carbon was significantly decreased by root interaction. In addition, straw mulching promoted while green manure intercropping inhibited the soil respiration. Soil respiration presented the general characteristics of fall-rise-fall due to the strong influence of rape growth period. Therefore, it showed a cubic curve relationship with soil temperature.


Asunto(s)
Agricultura/métodos , Brassica rapa/crecimiento & desarrollo , Carbono/análisis , Estiércol , Rizosfera , Suelo/química , China , Monitoreo del Ambiente , Estaciones del Año , Temperatura
4.
Artículo en Inglés | MEDLINE | ID: mdl-21375929

RESUMEN

OBJECTIVE: To elucidate the growth and development of patients with Cushing's syndrome (CS) in adolescence. METHODS: We analyzed the clinical data of 19 patients aged under 18 with CS. We divided the patients into two groups according to the height at diagnosis. The patients under the 3rd percentile were in the short stature group (n=12), and the others in the non-short stature group (n=7). The intergroup differences in disease course, age of onset, and 24-hour urinary free cortisol were analyzed. RESULTS: The median age at diagnosis was 13 years. The median disease course was 0.9 years. All those patients presented with typical clinical characteristics of CS. Twelve cases (63.2%) were in short stature group. The disease course of the short stature group was found significantly longer than that of the non-short stature group [(2.7∓1.7) years vs. (0.8∓0.6) years, P=0.013], but no significant difference was found in the age of onset (P=0.530) or 24-hour urinary free cortisol (P=0.919) between the two groups. CONCLUSIONS: The data suggest that short stature is common in adolescent CS patients. The growth delay may be correlated to the disease course of CS.


Asunto(s)
Desarrollo del Adolescente/fisiología , Síndrome de Cushing/fisiopatología , Adolescente , Niño , Femenino , Humanos , Masculino , Estudios Retrospectivos
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