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1.
Chem Commun (Camb) ; 60(9): 1112-1115, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38180482

RESUMO

A photoacoustic (PA) imaging probe, HCy-SH, was designed and synthesized. This probe can react rapidly and specifically with sulfane sulfur to produce a strong PA signal. This probe also exhibited low cytotoxicity and biotoxicity. Thus, HCy-SH has been used for visual diagnosis of acute cerebral ischemia.


Assuntos
Isquemia Encefálica , Técnicas Fotoacústicas , Humanos , Enxofre , Diagnóstico por Imagem , Isquemia Encefálica/diagnóstico por imagem
2.
Chem Commun (Camb) ; 59(76): 11381-11384, 2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37665627

RESUMO

A novel biodegradable layered double hydroxide-copper selenide nanocomplex was prepared by anchoring copper selenide on manganese iron layered double hydroxide nanosheets. This nanocomplex can specifically release CuSe, Mn2+ and Fe3+ in the tumor microenvironment, which implements NIR-II photoacoustic imaging-guided synergistic cancer therapy under 1064 nm laser irradiation.


Assuntos
Neoplasias , Técnicas Fotoacústicas , Humanos , Manganês , Cobre , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Hidróxidos , Ferro , Microambiente Tumoral
3.
Anal Chem ; 95(12): 5384-5392, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36811909

RESUMO

Unravelling the pathophysiology of depression is a unique challenge. Depression is closely associated with reduced norepinephrine (NE) levels; therefore, developing bioimaging probes to visualize NE levels in the brain is a key to elucidating the pathophysiological process of depression. However, because NE is similar in structure and chemical properties to two other catecholamine neurotransmitters, epinephrine and dopamine, designing an NE-specific multimodal bioimaging probe is a difficult task. In this work, we designed and synthesized the first near-infrared fluorescent-photoacoustic (PA) dual-modality imaging probe for NE (FPNE). The ß-hydroxyethylamine of NE was shown to react via nucleophilic substitution and intramolecular nucleophilic cyclization, resulting in the cleavage of a carbonic ester bond in the probe molecule and release of a merocyanine molecule (IR-720). This process changed the color of the reaction solution from blue-purple to green, and the absorption peak was red-shifted from 585 to 720 nm. Under light excitation at 720 nm, linear relationships between the concentration of NE and both the PA response and the fluorescence signal intensity were observed. Thus, the use of intracerebral in situ visualization for diagnosis of depression and monitoring of drug interventions was achieved in a mouse model by fluorescence and PA imaging of brain regions after administration of FPNE by tail-vein injection.


Assuntos
Depressão , Diagnóstico por Imagem , Animais , Camundongos , Diagnóstico por Imagem/métodos , Norepinefrina/química , Norepinefrina/farmacologia , Espectrometria de Fluorescência , Encéfalo/diagnóstico por imagem
4.
Ying Yong Sheng Tai Xue Bao ; 31(3): 987-998, 2020 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-32537996

RESUMO

Ecological land is essential to sustainable development of urban agglomeration. Based on the results of remote sensing image interpretation, we analyzed the spatial-temporal evolution of ecological land in 32 research units of ecological land in Wuhan urban agglomeration in 2000-2005, 2005-2010 and 2010-2015, using the land use transition matrix, exploratory regression analysis, the ordinary least squares (OLS) model, and geographically weighted regression (GWR) model. Then, the best regression model was selected after perfecting the traditional index system of influencing factors by data of the location and quantitative information of companies, enterprises and life services, etc., and conducting exploratory regression analysis. Finally, we analyzed the influencing factors and spatial differentiation rules of different research periods with GWR model. The results showed that, from 2000 to 2015, the amount of transition from ecological land use to non-ecological land use in the urban agglomeration showed an inverted U-shaped change pattern, and the space showing the expanding trend from point to surface. Land use patterns of 8.4% area had changed in the urban agglomeration, among which the conversion of cultivated land, forest land, grassland, water body and unused land to non-ecological land accounted for 41.9% of the total area. The spatial pattern gradually expanded from the central urban area of Wuhan to the periphery of the municipal sub-center and county-level towns. The total number of passing models in the three stages of exploratory regression analysis was 326. The GWR and OLS regression were used for comparative analysis of all models. The adjusted R2 in the three stages of selected models were 0.83, 0.91 and 0.76, respectively. The former improved by 0.02, 0.03 and 0.02, and the AICc decreased by 2.88, 3.42 and 0.83, respectively. The results of GWR model showed substantially spatial differentiation of influencing factors of ecological land evolution in Wuhan urban agglomeration, and that the influence patterns was dominated by gradual transition in different directions in space, with other patterns such as "V" distribution. The effects of spatial factors were significant. The potential information of spatial data enhanced the interpretation of ecological land evolution within the urban agglomeration.


Assuntos
Monitoramento Ambiental , Regressão Espacial , China , Cidades , Florestas , Análise dos Mínimos Quadrados
5.
Entropy (Basel) ; 21(1)2018 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-33266736

RESUMO

As complex systems, the spatial structure of urban systems can be analyzed by entropy theory. This paper first calculates the interaction force between cities based on the gravity model, the spatial relationship matrix between cities is constructed using the method of network modeling, and the spatial network modeling of urban system can be calculated. Secondly, the Efficiency Entropy (EE), Quality Entropy (QE), and System Entropy (SE) of urban system network are calculated and analyzed by information entropy. Finally, taking the Huaihe River Basin (HRB) as a case study, model verification and empirical analysis are performed. It is found that the spatio-temporal pattern of the urban system network structure in the basin is uneven: in space, the urban system network in the HRB presents a layer-by-layer spatial distribution centered on the core city of Xuzhou; meanwhile, the overall urban system network in the basin presents an orderly development trend. This study has certain theoretical and practical value for the planning of urban and urban systems and the coordinated development of regions.

6.
Huan Jing Ke Xue ; 38(12): 5352-5366, 2017 Dec 08.
Artigo em Chinês | MEDLINE | ID: mdl-29964600

RESUMO

Streams and rivers play a major biogeochemical role in the global carbon cycle and act as hot spots for carbon dioxide (CO2) and methane (CH4) emissions to the atmosphere, excepting their roles of transporting the water and carbon from the terrestrial environment to the ocean. While carbon gases have been of great global concern, systematic reviews are still scarce. Given recent recognition of the pervasiveness of CO2 and CH4 in streams and rivers, this study synthesized existing research and discoveries to identify patterns and controls for riverine CO2 and CH4, knowledge gaps, and research opportunities. This study presented a conceptual framework for sources and the fates of CO2/CH4 from streams and rivers and used this framework to understand the dynamic processes of fluvial carbon evasion and potential anthropogenic disturbances. Multiple environmental influences combined with different contributions of endogenous metabolism and terrigenous input, and the CO2 and CH4 in streams and rivers showed significant spatial and temporal variability on a global scale, regional scale, and watershed scale, which indicates a substantial challenge for understanding the larger-scale dynamics. For a clearer recognition of how the changing environment and human activities may modify fluvial CO2 and CH4 dynamics, this study constructed a system framework of controls on CO2 and CH4 production and persistence in streams and rivers. The framework of controls can be viewed in terms of endogenous environmental controls that influence river metabolism (organic matter, temperature, nutrients, pH, and alternative electron acceptors) and external factors, including geomorphic and hydrologic drivers and human activities (agriculture, damming, and urbanization). We point out that the carbon emissions from rivers should be integrated into the terrestrial carbon budget, and in the future, more attention should be given to research on the sources of CO2 and CH4 in rivers, the generation and diffusion of CO2 and CH4 at different interfaces, the spatiotemporal variability of riverine carbon emissions, and the response of riverine CO2 and CH4 dynamics to the changing environment and human activities.

7.
Int J Med Mushrooms ; 17(7): 693-700, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26559703

RESUMO

Ophiocordyceps sinensis (syn. Cordyceps sinensis), well known as DongChongXiaCao (DCXC), is one of the most valuable traditional Chinese medicinal species. In this article, we provide a systematic review of natural enemies and diseases encountered in artificial cultivation of DCXC. Unfortunately, DCXC has been endangered over the past decades due to overharvesting and a worsening ecological environment. Therefore, the artificial cultivation of DCXC has been extensively investigated in recent years. Complete indoor artificial cultivation and semi-field cultivation are the two most common strategies used to cultivate DCXC. However, cultured DCXCs are often attacked by various natural enemies and diseases, which have resulted in substantial loss of the valuable medicinal resource. In this study, we have summarized the species of natural enemies and types of diseases confronted by DCXC. Twenty reported natural enemy species are categorized into four classes, one of which is reported for the first time in this study. Moreover, six microbial pathogens are also discussed. The recapitulation of the natural enemies and diseases in DCXC artificial cultivation not only promote the development of integrated pest management of DCXC cultivation but also provide important information to help preserve and develop this valuable resource.


Assuntos
Hypocreales/crescimento & desenvolvimento , Animais , China , Besouros , Espécies em Perigo de Extinção , Larva/microbiologia , Medicina Tradicional Chinesa/economia , Mariposas/crescimento & desenvolvimento , Mariposas/microbiologia , Mariposas/parasitologia , Tibet
8.
Zhong Yao Cai ; 37(10): 1729-33, 2014 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-25895376

RESUMO

OBJECTIVE: To explore the phenological characteristics of Polygonum viviparum introduced from high altitude to low altitude area. METHODS: To introduce the root and seed of Polygonum viviparum from high altitude to low altitude area and collect their growth and phenological data. RESULTS: In low altitude area, Polygonum viviparum germinated at the beginning of March, grew from March to the end of July, withered during the whole August due to high temperature, recovered from the end of August to the beginning of October, and then withered again due to low temperature. Its reproduction lasted from April to the end of July, stagnated from the beginning of August to the middle of September, and recovered from the middle of September to the end of October. CONCLUSION: The high temperature of August in low altitude area is the bottleneck season for Polygonum viviparum, yet it can grow normally while such technologies are applied to its culture as early seeding, culture seedling with fertilizing soil ball, complete overshadow etc.


Assuntos
Altitude , Polygonum/fisiologia , Germinação , Raízes de Plantas/fisiologia , Estações do Ano , Sementes/fisiologia , Solo
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