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1.
BMC Endocr Disord ; 24(1): 19, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38311763

RESUMO

BACKGROUND: We assessed the value of positron emission tomography/computed tomography (PET/CT) with [13N]N-ammonia ([13N]N-NH3) and [11C]C-methionine ([11C]C-MET) for the evaluation and management of recurrent secreting pituitary adenoma, which could not be detected by magnetic resonance imaging (MRI) or fluorine-18 fluorodeoxyglucose ([18F]F-FDG) PET. METHODS: Nine consecutive patients with biochemical and clinical evidence of active recurrent tumor not detected by MRI and [18F]F-FDG PET were enrolled in this study. All of the patients underwent [13N]N-NH3 and [11C]C-MET PET/CT, after which the pattern of tracer uptake was studied, the tumor position was located, and a clinical decision was made. RESULTS: In general, [11C]C-MET had a higher uptake in pituitary adenomas (PAs) than that in pituitary tissues, while [13N]N-NH3 had a higher uptake in pituitary tissue than in pituitary adenomas. Increased [11C]C-MET uptake was observed in all nine PAs and three pituitary tissues, while all pituitary tissues and only one pituitary adenoma showed increased [13N]N-NH3 uptake. Four patients had concordant imaging and surgical findings indicative of biochemical remission without hypopituitarism after treatment. Radiotherapy was adopted in two patients, medication in another two, and follow-up observation in one case. CONCLUSION: Combined [11C]C-MET and [13N]N-NH3 PET/CT is effective in the differentiation of PAs from pituitary tissue in recurrent functional PAs with negative MRI or [18F]F-FDG PET. These results provide a valuable reference for further disease management.


Assuntos
Adenoma , Neoplasias Hipofisárias , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Fluordesoxiglucose F18 , Neoplasias Hipofisárias/diagnóstico por imagem , Neoplasias Hipofisárias/patologia , Metionina , Amônia , Recidiva Local de Neoplasia/diagnóstico por imagem , Adenoma/diagnóstico por imagem , Adenoma/patologia , Tomografia por Emissão de Pósitrons/métodos , Racemetionina , Imageamento por Ressonância Magnética/métodos , Compostos Radiofarmacêuticos
3.
Glob Chang Biol ; 29(18): 5460-5477, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37357413

RESUMO

The long-term use of cropland and cropland reclamation from natural ecosystems led to soil degradation. This study investigated the effect of the long-term use of cropland and cropland reclamation from natural ecosystems on soil organic carbon (SOC) content and density over the past 35 years. Altogether, 2140 topsoil samples (0-20 cm) were collected across Northeast China. Landsat images were acquired from 1985 to 2020 through Google Earth Engine, and the reflectance of each soil sample was extracted from the Landsat image that its time was consistent with sampling. The hybrid model that included two individual SOC prediction models for two clustering regions was built for accurate estimation after k-means clustering. The probability hybrid model, a combination between the hybrid model and classification probabilities of pixels, was introduced to enhance the accuracy of SOC mapping. Cropland reclamation results were extracted from the land cover time-series dataset at a 5-year interval. Our study indicated that: (1) Long-term use of cropland led to a 3.07 g kg-1 and 6.71 Mg C ha-1 decrease in SOC content and density, respectively, and the decrease of SOC stock was 0.32 Pg over the past 35 years; (2) nearly 64% of cropland had a negative change in terms of SOC content from 1985 to 2020; (3) cropland reclamation track changed from high to low SOC content, and almost no cropland was reclaimed on the "Black soils" after 2005; (4) cropland reclamation from wetlands resulted in the highest decrease, and reclamation period of years 31-35 decreased when SOC density and SOC stock were 16.05 Mg C ha-1 and 0.005 Pg, respectively, while reclamation period of years 26-30 from forest witnessed SOC density and stock decreases of 8.33 Mg C ha-1 and 0.01 Pg, respectively. Our research results provide a reference for SOC change in the black soil region of Northeast China and can attract more attention to the area of the protection of "Black soils" and natural ecosystems.

4.
Glob Chang Biol ; 29(21): 6139-6156, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37641440

RESUMO

Robust estimates of wetland soil organic carbon (SOC) pools are critical to understanding wetland carbon dynamics in the global carbon cycle. However, previous estimates were highly variable and uncertain, due likely to the data sources and method used. Here we used machine learning method to estimate SOC storage and their changes over time in China's wetlands based on wetland SOC density database, associated geospatial environmental data, and recently published wetland maps. We built a database of wetland SOC density in China that contains 809 samples from 181 published studies collected over the last 20 years as presented in the published literature. All samples were extended and standardized to a 1-m depth, on the basis of the relationship between SOC density data from soil profiles of different depths. We used three different machine learning methods to evaluate their robustness in estimating wetland SOC storage and changes in China. The results indicated that random forest model achieved accurate wetland SOC estimation with R2 being .65. The results showed that average SOC density of top 1 m in China's wetlands was 25.03 ± 3.11 kg C m-2 in 2000 and 26.57 ± 3.73 kg C m-2 in 2020, an increase of 6.15%. SOC storage change from 4.73 ± 0.58 Pg in 2000 to 4.35 ± 0.61 Pg in 2020, a decrease of 8.03%, due to 13.6% decreased in wetland area from 189.12 × 103 to 162.8 × 103 km2 in 2020, despite the increase in SOC density during the same time period. The carbon accumulation rate was 107.5 ± 12.4 g C m-2 year-1 since 2000 in wetlands with no area changes. Climate change caused variations in wetland SOC density, and a future warming and drying climate would lead to decreases in wetland SOC storage. Estimates under Shared Socioeconomic Pathway 1-2.6 (low-carbon emissions) suggested that wetland SOC storage in China would not change significantly by 2100, but under Shared Socioeconomic Pathway 5-8.5 (high-carbon emissions), it would decrease significantly by approximately 5.77%. In this study, estimates of wetland SOC storage were optimized from three aspects, including sample database, wetland extent, and estimation method. Our study indicates the importance of using consistent SOC density and extent data in estimating and projecting wetland SOC storage.

5.
Int J Mol Sci ; 24(14)2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37511108

RESUMO

Abscisic acid (ABA) plays a vital role in the induction of low temperature tolerance in plants. To understand the molecular basis of this phenomenon, we performed a proteomic analysis on an ABA-deficit mutant barley (Az34) and its wild type (cv Steptoe) under control conditions (25/18 °C) and after exposure to 0 °C for 24 h. Most of the differentially abundant proteins were involved in the processes of photosynthesis and metabolisms of starch, sucrose, carbon, and glutathione. The chloroplasts in Az34 leaves were more severely damaged, and the decrease in Fv/Fm was larger in Az34 plants compared with WT under low temperature. Under low temperature, Az34 plants possessed significantly higher activities of ADP-glucose pyrophosphorylase, fructokinase, monodehydroascorbate reductase, and three invertases, but lower UDP-glucose pyrophosphorylase activity than WT. In addition, concentrations of proline and soluble protein were lower, while concentration of H2O2 was higher in Az34 plants compared to WT under low temperature. Collectively, the results indicated that ABA deficiency induced modifications in starch and sucrose biosynthesis and sucrolytic pathway and overaccumulation of reactive oxygen species were the main reason for depressed low temperature tolerance in barley, which provide novel insights to the response of barley to low temperature under future climate change.


Assuntos
Ácido Abscísico , Hordeum , Ácido Abscísico/metabolismo , Hordeum/metabolismo , Proteômica , Peróxido de Hidrogênio/metabolismo , Fotossíntese , Amido/metabolismo , Sacarose/metabolismo , Oxirredução , Homeostase , Regulação da Expressão Gênica de Plantas
6.
Glob Chang Biol ; 28(7): 2327-2340, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34995391

RESUMO

Algal blooms (ABs) in inland lakes have caused adverse ecological effects, and health impairment of animals and humans. We used archived Landsat images to examine ABs in lakes (>1 km2 ) around the globe over a 37-year time span (1982-2018). Out of the 176032 lakes with area >1 km2 detected globally, 863 were impacted by ABs, 708 had sufficiently long records to define a trend, and 66% exhibited increasing trends in frequency ratio (FRQR, ratio of the number of ABs events observed in a year in a given lake to the number of available Landsat images for that lake) or area ratio (AR, ratio of annual maximum area covered by ABs observed in a lake to the surface area of that lake), while 34% showed a decreasing trend. Across North America, an intensification of ABs severity was observed for FRQR (p < .01) and AR (p < .01) before 1999, followed by a decrease in ABs FRQR (p < .01) and AR (p < .05) after the 2000s. The strongest intensification of ABs was observed in Asia, followed by South America, Africa, and Europe. No clear trend was detected for the Oceania. Across climatic zones, the contributions of anthropogenic factors to ABs intensification (16.5% for fertilizer, 19.4% for gross domestic product, and 18.7% for population) were slightly stronger than climatic drivers (10.1% for temperature, 11.7% for wind speed, 16.8% for pressure, and for 11.6% for rainfall). Collectively, these divergent trends indicate that consideration of anthropogenic factors as well as climate change should be at the forefront of management policies aimed at reducing the severity and frequency of ABs in inland waters.


Assuntos
Monitoramento Ambiental , Eutrofização , Animais , Mudança Climática , Monitoramento Ambiental/métodos , Lagos , Vento
7.
J Environ Manage ; 323: 116242, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36261984

RESUMO

The Sustainable Development Goals (SDGs) and the Convention on Biological Diversity's 15th Conference of the Parties (CBD COP15) both emphasized the urgency of protecting biological diversity. Spartina alterniflora (S. alterniflora), as an invasive species in China, has posed severe biodiversity challenges, demanding nationwide control and management. This study aims to assess the effectiveness of S. alterniflora management during China's SDGs implementation from 2015 to 2020. Landsat images acquired in 2015 (the beginning year of SDGs), 2018, and 2020 (the end year of SDGs' targets 6.6, 14.2, 14.5, and 15.8 related to alien invasion) were applied to quantify the spatiotemporal dynamics of S. alterniflora extent. The results revealed a consistent shrinkage of S. alterniflora, with a net areal reduction of 2610 ha from 2015 to 2020, implying the effectiveness of control measures on S. alterniflora invasion. Provinces including Zhejiang, Jiangsu, and Shanghai have succeeded in controlling S. alterniflora, evidenced by the sharp reduction in S. alterniflora area by 4908 ha, 2176 ha, and 1034 ha, respectively, from 2015 to 2020. However, better management of S. alterniflora is needed in regions with more severe S. alterniflora invasion, e.g., Shandong, Fujian, and Guangdong provinces. Our results suggest that relevant policies, regulations, and ecological restoration projects implemented by national or local governments in China received satisfactory results in S. alterniflora control. Nevertheless, S. alterniflora potential utilities and its governance effectiveness should be objectively evaluated and weighed to obtain the greatest ecological benefits and promote sustainable coastal ecosystems. The results of this study are expected to provide important baseline information benefitting the formulation of coastal protection and restoration strategies in China.


Assuntos
Ecossistema , Áreas Alagadas , Desenvolvimento Sustentável , China , Poaceae , Espécies Introduzidas
8.
J Environ Manage ; 280: 111670, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33218828

RESUMO

According to the United Nations Sustainable Development Goals (SDGs), understanding the extent of wetlands, their change trends and the proximate causes is important for the conservation of wetlands and endangered waterfowls. Here we studied the world's ninth largest river basin, the Amur River Basin (ARB), with a land area of 2.08 million km2. Our objectives were to address the information deficiencies of spatially explicit wetland distributions and their changes and to quantify the proximate causes of these changes in various periods in the ARB. A hybrid approach combining object-based and hierarchical decision-trees classification (HOHC) was applied to Landsat series images to obtain multitemporal land cover datasets from 1980 to 2016. Further quantitative analysis revealed that the ARB held 184,561 km2 of wetlands in 2016, accounting for 9% of the whole basin area. Among these, 59% of the wetlands were identified on the Russian side, while 40% were on the Chinese side, and 1% were on the Mongolian side. The ARB lost 22% of its wetland (52,246 km2) from 1980 to 2016, with a consistent net loss from 1980 to 2010 but an area gain from 2010 to 2016. Human activities dominated the consistent wetland losses on the Chinese side of the ARB, of which cropland expansion was the primary proximate cause of wetland loss (69%). Conversely, the wetlands on the Russian side had consistent losses from 1980 to 2010 followed by a gain from 2010 to 2016, which could be attributed to climate change. These quantified data will inform decision-making on wetland conservation and benefit scientific studies depending on spatially explicit wetland information.


Assuntos
Conservação dos Recursos Naturais , Áreas Alagadas , Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina , Povo Asiático , Monitoramento Ambiental , Humanos , Rios , Federação Russa
9.
J Environ Manage ; 290: 112618, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33866089

RESUMO

China's surface mining greatly supported the rapid socio-economic development; however, there was a scarcity in the systematic understanding of national changes in surface mining changes and associated ecosystem services (ESs) losses, which inevitably affected human well-being and limited sustainable ecosystem management and policy optimization. In this study, we quantified the areal changes in surface mining based on the ChinaCover database and performed further analysis of ES loss from expanded surface mining using multidimensional geospatial data from 1990 to 2015, including MODIS products, meteorological records, and statistical datasets. Our observations reveal that China's surface mining was estimated to be 4746 km2 in 2015 and that Inner Mongolia had the largest surface mining area (28%). Surface mining expanded remarkably from 1990 to 2015, with an increase by 2.7 times after 2000. In particular, Inner Mongolia, Shanxi, and Qinghai had the greatest increases in surface mining area. Rapid expansion of surface mining led to obvious declines in natural habitat area, water retention, net primary productivity, and grain production, and these ES losses showed apparent spatiotemporal variations. China has taken many measures to reclaim the abandoned surface mining sites. Given the rapid expansion of surface mining and related ES loss, China should continue to perform ecological restoration for its sustainability.


Assuntos
Ecossistema , Mineração , China , Conservação dos Recursos Naturais , Desenvolvimento Econômico , Humanos , Políticas
10.
J Environ Manage ; 278(Pt 2): 111549, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33260073

RESUMO

China's coastal wetlands are critically important to shorebirds. Substantial loss of tidal flats, shorebirds' primary foraging grounds, has occurred from land claim and other processes, and is driving population declines in multiple species. Smooth cordgrass Spartina alterniflora was intentionally introduced to the coast of China in 1979 to promote conversion of tidal flats into dry land and has since spread rapidly. The occurrence of S. alterniflora reduces the availability of foraging and roosting habitat for shorebirds, and may be particularly detrimental in places that have experienced other tidal flat loss. However, the extent to which S. alterniflora is encroaching upon important shorebird habitat throughout coastal mainland China, and its intersection with tidal flat loss, has not been quantified. Here, we i) estimate change in the spatial extent of tidal flats between 2000 and 2015 in coastal mainland China where internationally important numbers of shorebirds have been recorded; ii) map the extent of S. alterniflora coverage in 2015 at the same set of sites; and, iii) investigate where these two threats to important shorebird habitat intersect. Our analysis of remote sensing data indicated a 15% net loss in tidal flat area between 2000 and 2015 across all sites, including a net loss in tidal flat area in 39 of 53 individual sites (74%). Spartina alterniflora occurred at 28 of 53 sites (53%) in 2015, of which 22 sites (79%) also had a net loss in tidal flat area between 2000 and 2015. Combined pressures from tidal flat loss and S. alterniflora invasion were most severe in eastern coastal China. Species highly dependent on migrating through this region, which include the Critically Endangered Spoon-billed Sandpiper and Endangered Nordmann's Greenshank and Far Eastern Curlew, may be particularly impacted. Our results underscore the urgent need to arrest tidal flat declines and develop a comprehensive control program for S. alterniflora in coastal areas of mainland China that are important for shorebirds.


Assuntos
Ecossistema , Poaceae , China , Espécies Introduzidas , Áreas Alagadas
11.
Br J Neurosurg ; 34(5): 487-491, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29667493

RESUMO

Objective: Pituicytomas and granular cell tumours (GCTs) of the neurohypophysis are considered non-adenomatous neoplasms in the sellar region. The association between hormone hypersecretion and the tumours is seldom discussed and unclear. Therefore, we attempt to investigate this association based on our experience and a review of the literature.Methods: We report three patients who presented with Cushing's syndrome- or acromegaly-like symptoms at our institution. They underwent transsphenoidal surgery for suspected pituitary adenomas, which were subsequently diagnosed as pituicytomas or hypophyseal GCTs following histological and immunohistochemical analysis. We also review previously reported relevant cases of pituitary non-adenomatous tumours in the literature.Results: Four cases of Cushing's syndrome with pituicytoma and one case of acromegaly with a GCT have recently been reported. In the three cases presented here, one patient with Cushing's syndrome and one patient with acromegaly also had a pituicytoma, while the second patient with acromegaly had a GCT.Conclusions: Rather than mere coexistence of non-adenomatous pituitary tumours with hypersecretory adenomas or hyperplasia, alternative causes for the observed symptoms maybe the presence of some unidentified substances produced by the tumours that stimulate the adenohypophysis to secrete pituitary hormones. The glial cells of the pituitary gland may play an important role in oncogenic differentiation and regulation of the release of hormones. Therefore, attention should be focused on investigating the origin and functions of glial cells.


Assuntos
Adenoma , Neoplasias Hipofisárias , Acromegalia/diagnóstico , Adenoma/diagnóstico , Adenoma/cirurgia , Síndrome de Cushing , Humanos , Hipófise , Neoplasias Hipofisárias/diagnóstico , Neoplasias Hipofisárias/cirurgia
12.
Sensors (Basel) ; 20(24)2020 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-33302357

RESUMO

Accurate prediction of wetland soil organic carbon concentration and an understanding of its controlling factors are important for studying regional climate change and wetland carbon cycles; with that knowledge mechanisms can be put in place that are conducive to sustainable ecosystem management for environmental health. In this study, a hybrid approach combining an artificial neural network and ordinary kriging and 103 soil samples at three soil depth ranges (0-30, 30-60, and 60-100 cm) were used to predict wetland soil organic carbon concentration in China's Liao River Basin. The model evaluation indicated that a combination of artificial neural network and ordinary kriging and limited soil samples achieved good performance in predicting wetland soil organic carbon concentration. Wetland soil organic carbon concentration in the Liao River Basin has apparent spatial and vertical heterogeneities with values decreasing from southeast to northwest and concentrates present mainly in the topsoil (0-30 cm). Mean wetland soil organic carbon concentration values at the three soil depths were 10.43 ± 0.38, 7.93 ± 0.25, and 7.61 ± 0.22 g/kg, respectively, which are smaller than those over other wetland regions in Northeast China. Terrain aspect contributed the most in predicting wetland soil organic carbon concentration at each of the three soil depths, followed by normalized difference vegetation index at 0-30 cm and mean annual precipitation at 30-60 and 60-100 cm. This study provides a framework method and baseline to quantify the soil organic carbon concentration dynamics in response to climatic and anthropogenic drivers.

13.
J Environ Manage ; 267: 110623, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32364128

RESUMO

China implemented the National Wetland Conservation Program (NWCP) from 2002 to protect and rehabilitate wetlands. Under the background of sustainable development, assessment on the effectiveness of the NWCP is important to ecosystem management, especially in the Sanjiang Plain, the largest marsh distribution area and hotspot area with wetland loss. To achieve this aim, this study examined the changes in land cover and ecosystem services (ESs) from 1990 to 2000 and from 2000 to 2015 in the Sanjiang Plain as well as the nine national nature reserves for wetlands (NNRWs) by means of Landsat series images and the InVEST model. Results reveal that the NWCP played critical roles in reducing wetland loss and improving regional ESs. The shrinkage rate of wetlands in the Sanjiang Plain has been decreased remarkably, with a declined rate of wetland loss from 750 km2 yr-1 to 189 km2 yr-1. The reduction rate of habitat area in good suitable grade and ecosystem carbon stock declined notably during the period 2000-2015 compared to the period 1990-2000. The amount of water retention increased by 5.4%, while the grain production capacity was enhanced by nine times from 1990 to 2015. Specifically, since 2000, the reduction rate of wetland area in NNRWs (33 km2 yr-1) was obviously lower than that in the entire Sanjiang Plain, whilst various ESs in NNRWs were better than that in the whole Sanjiang Plain. This study is expected to provide an example for evaluating the effectiveness of the NWCP at other regions and support regional wetland conservation management.


Assuntos
Ecossistema , Áreas Alagadas , Agricultura , China , Conservação dos Recursos Naturais
14.
Biochem Biophys Res Commun ; 520(1): 79-85, 2019 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-31582213

RESUMO

Prolactinoma is a clinically common intracranial tumor. When serum prolactin levels are not controlled despite administration of a dopamine agonist, the condition is referred to as drug-resistant prolactinoma. The mechanism underlying persistent prolactin secretion in drug-resistant prolactinoma remains unclear. MicroRNAs play an important role in tumorigenesis and development as well as chemotherapeutic resistance. This study was conducted to investigate the mechanism by which miRNA regulates prolactin secretion in drug-resistant prolactinoma. We first found that miR-1299 was elevated in drug-resistant prolactinoma and inhibited FOXO1 in a targeted manner through miRNA sequencing and luciferase assays. We then confirmed that FOXO1 binds to the promoter of the prolactin gene to inhibit its expression through chromatin immunoprecipitation-quantitative PCR and cytological experiments. Finally, inhibition or overexpression of miR-1299 in primary tumor cells confirmed that drug-resistant prolactinoma promoted prolactin secretion by promoting miR-1299 expression and reducing intracellular FOXO1. These results indicate that FOXO1 and miR-1299 are potential therapeutic targets for drug-resistant prolactinoma as well as other pituitary diseases.


Assuntos
Resistencia a Medicamentos Antineoplásicos , MicroRNAs/fisiologia , Proteínas do Tecido Nervoso/metabolismo , Neoplasias Hipofisárias/metabolismo , Prolactina/sangue , Prolactinoma/metabolismo , Regiões 3' não Traduzidas , Animais , Linhagem Celular Tumoral , Proteína Forkhead Box O1/metabolismo , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hipofisárias/tratamento farmacológico , Prolactinoma/tratamento farmacológico , Ratos , Transfecção
15.
Exp Mol Pathol ; 107: 124-128, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30776356

RESUMO

PURPOSE: Liraglutide, a glucagon-like peptide-1 (GLP-1) analogue, is an antidiabetic drug. It has been shown to improve the Psoriasis Area and Severity Index (PASI) in patients with type 2 diabetes and psoriasis in clinical practice, but the mechanism remains somewhat unclear. We used lipopolysaccharides (LPS) to induce inflammatory response in keratinocytes and explore the mechanism. METHODS: The HaCat cells were incubated with LPS for 16 h and then were treated with liraglutide for 30 min. Cell viability was testing by CCK-8 assay. GLP-1Rs and intracellular signaling pathways were identified by Western blot. The migration of macrophage was detecting by trans-well assay. RESULTS: Liraglutide decreased cell viability in the HaCat cells. Liraglutide restrained the migration of macrophage to the HaCat cells. LPS elevated not only the protein abundance of phospho-IKKα/ß S176/S180, phospho-NF-κB p65, phospho-JAK2, phospho-STAT3 and SOCS3, but also the levels of TNF-α and IL-6 in the HaCat cells. These effects of LPS were reversed by liraglutide. In addition, liraglutide increased phosphorylation of AMPK. The AMPK inhibitor Compound (CC) impaired liraglutide-inhibited p-NF-κB p65 and p-STAT3. CONCLUSIONS: GLP-1 impaired keratinocytes inflammatory signals by activating AMPK and restrained macrophage migration.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Hipoglicemiantes/farmacologia , Queratinócitos/efeitos dos fármacos , Liraglutida/farmacologia , Psoríase/fisiopatologia , Proteínas Quinases Ativadas por AMP/efeitos dos fármacos , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Humanos , Inflamação/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo
16.
Sensors (Basel) ; 19(10)2019 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-31109131

RESUMO

Given the extensive spread and ecological consequences of exotic Spartina alterniflora (S. alterniflora) over the coast of mainland China, monitoring its spatiotemporal invasion patterns is important for the sake of coastal ecosystem management and ecological security. In this study, Landsat series images from 1990 to 2015 were used to establish multi-temporal datasets for documenting the temporal dynamics of S. alterniflora invasion. Our observations revealed that S. alterniflora had a continuous expansion with the area increasing by 50,204 ha during the considered 25 years. The largest expansion was identified in Jiangsu Province during the period of 1990-2000, and in Zhejiang Province during the periods 2000-2010 and 2010-2015. Three noticeable hotspots for S. alterniflora invasion were Yancheng of Jiangsu, Chongming of Shanghai, and Ningbo of Zhejiang, and each had a net area increase larger than 5000 ha. Moreover, an obvious shrinkage of S. alterniflora was identified in three coastal cities including the city of Cangzhou of Hebei, Dongguan, and Jiangmen of Guangdong. S. alterniflora invaded mostly into mudflats (>93%) and shrank primarily due to aquaculture (55.5%). This study sheds light on the historical spatial patterns in S. alterniflora distribution and thus is helpful for understanding its invasion mechanism and invasive species management.


Assuntos
Técnicas Biossensoriais/métodos , Ecossistema , Monitoramento Ambiental/métodos , Poaceae/fisiologia , China , Humanos , Espécies Introduzidas
17.
Sensors (Basel) ; 18(12)2018 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-30558356

RESUMO

Forest plays a significant role in the global carbon budget and ecological processes. The precise mapping of forest cover can help significantly reduce uncertainties in the estimation of terrestrial carbon balance. A reliable and operational method is necessary for a rapid regional forest mapping. In this study, the goal relies on mapping forest and subcategories in Northeast China through the use of high spatio-temporal resolution HJ-1 imagery and time series vegetation indices within the context of an object-based image analysis and decision tree classification. Multi-temporal HJ-1 images obtained in a single year provide an opportunity to acquire phenology information. By analyzing the difference of spectral and phenology information between forest and non-forest, forest subcategories, decision trees using threshold values were finally proposed. The resultant forest map has a high overall accuracy of 0.91 ± 0.01 with a 95% confidence interval, based on the validation using ground truth data from field surveys. The forest map extracted from HJ-1 imagery was compared with two existing global land cover datasets: GlobCover 2009 and MCD12Q1 2009. The HJ-1-based forest area is larger than that of MCD12Q1 and GlobCover and more closely resembles the national statistics data on forest area, which accounts for more than 40% of the total area of the Northeast China. The spatial disagreement primarily occurs in the northern part of the Daxing'an Mountains, Sanjiang Plain and the southwestern part of the Songliao Plain. The compared result also indicated that the forest subcategories information from global land cover products may introduce large uncertainties for ecological modeling and these should be cautiously used in various ecological models. Given the higher spatial and temporal resolution, HJ-1-based forest products could be very useful as input to biogeochemical models (particularly carbon cycle models) that require accurate and updated estimates of forest area and type.

18.
Sensors (Basel) ; 18(4)2018 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-29614727

RESUMO

Soil salinity and sodicity can significantly reduce the value and the productivity of affected lands, posing degradation, and threats to sustainable development of natural resources on earth. This research attempted to map soil salinity/sodicity via disentangling the relationships between Landsat 8 Operational Land Imager (OLI) imagery and in-situ measurements (EC, pH) over the west Jilin of China. We established the retrieval models for soil salinity and sodicity using Partial Least Square Regression (PLSR). Spatial distribution of the soils that were subjected to hybridized salinity and sodicity (HSS) was obtained by overlay analysis using maps of soil salinity and sodicity in geographical information system (GIS) environment. We analyzed the severity and occurring sizes of soil salinity, sodicity, and HSS with regard to specified soil types and land cover. Results indicated that the models' accuracy was improved by combining the reflectance bands and spectral indices that were mathematically transformed. Therefore, our results stipulated that the OLI imagery and PLSR method applied to mapping soil salinity and sodicity in the region. The mapping results revealed that the areas of soil salinity, sodicity, and HSS were 1.61 × 106 hm², 1.46 × 106 hm², and 1.36 × 106 hm², respectively. Also, the occurring area of moderate and intensive sodicity was larger than that of salinity. This research may underpin efficiently mapping regional salinity/sodicity occurrences, understanding the linkages between spectral reflectance and ground measurements of soil salinity and sodicity, and provide tools for soil salinity monitoring and the sustainable utilization of land resources.

19.
Mar Drugs ; 13(3): 1569-80, 2015 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-25806467

RESUMO

Nonfunctioning pituitary adenoma (NFPA) is one of the most common types of pituitary adenoma. The marine anthraquinone derivative SZ-685C has been isolated from the secondary metabolites of the mangrove endophytic fungus Halorosellinia sp. (No. 1403) which is found in the South China Sea. Recent research has shown that SZ-685C possesses anticancer and tumor suppressive effects. The tetrazolium-based colorimetric assay (MTT assay) to investigate the different effect of the marine compound SZ-685C on the proliferation of primary human NFPA cells, rat normal pituitary cells (RPCs) and rat prolactinoma MMQ cell lines. Hoechst 33342 dye/propidium iodide (PI) double staining and fluorescein isothiocyanate-conjugated Annexin V/PI (Annexin V-FITC/PI) apoptosis assays detected an enhanced rate of apoptosis in cells treated with SZ-685C. Enhanced expression levels of caspase 3 and phosphate and tensin homolog (PTEN) were determined by Western blotting. Notably, the protein expression levels of Akt were decreased when the primary human NFPA cells were treated with SZ-685C. Here, we show that SZ-685C induces apoptosis of human NFPA cells through inhibition of the Akt pathway in vitro. The understanding of apoptosis has provided the basis for novel targeted therapies that can induce death in cancer cells or sensitize them to established cytotoxic agents and radiation therapy.


Assuntos
Antraquinonas/farmacologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias Hipofisárias/tratamento farmacológico , Adenoma/tratamento farmacológico , Adenoma/patologia , Animais , Antraquinonas/isolamento & purificação , Antineoplásicos/isolamento & purificação , Ascomicetos/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , China , Humanos , Neoplasias Hipofisárias/patologia , Prolactinoma/tratamento farmacológico , Prolactinoma/patologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Ratos , Metabolismo Secundário
20.
Environ Manage ; 54(2): 255-71, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24844462

RESUMO

This study investigated human-induced long-term wetland degradation that occurred in the Sanjiang Plain. Results from analyzing land-use/land-cover data sets derived from remotely sensed Landsat Multispectral Scanner/Thematic Mapper imagery for four time points showed that wetlands in the Sanjiang Plain have been severely transformed, and the area of wetlands decreased by 38 % from 1976 to 1986, by 16 % from 1986 to 1995, and by 31 % from 1995 to 2005. This study showed that transition to agricultural cultivation accounted for 91 % of wetland losses, whereas transition to grassland and forest accounted for 7 % of the wetlands losses. Institutional strategies and market policies probably exerted great impacts on agricultural practice that directly or indirectly influenced the decrease in wetlands. This study also indicated that an increased population likely led to wetland conversion to cropland by showing a high correlation between population and cropland (R (2) = 0.92, P < 0.001). Wetland loss occurred during later time intervals at a low rate. This study suggests that the existing wetland-protection measures in the Sanjiang Plain should be reinforced further because of possible environmental consequences of wetland loss, such as enhanced soil carbon emission, changed hydrological cycling, and regional temperature increase.


Assuntos
Agricultura/métodos , Conservação dos Recursos Naturais/estatística & dados numéricos , Meio Ambiente , Monitoramento Ambiental/estatística & dados numéricos , Crescimento Demográfico , Áreas Alagadas , China , Conservação dos Recursos Naturais/métodos , Monitoramento Ambiental/métodos , Humanos , Processamento de Imagem Assistida por Computador , Imagens de Satélites/métodos
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