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1.
J Environ Manage ; 353: 120202, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38308984

RESUMO

Surface water plays a crucial role in the ecological environment and societal development. Remote sensing detection serves as a significant approach to understand the temporal and spatial change in surface water series (SWS) and to directly construct long-term SWS. Limited by various factors such as cloud, cloud shadow, and problematic satellite sensor monitoring, the existent surface water mapping datasets might be short and incomplete due to losing raw information on certain dates. Improved algorithms are desired to increase the completeness and quality of SWS datasets. The present study proposes an automated framework to detect SWS, based on the Google Earth Engine and Landsat satellite imagery. This framework incorporates implementing a raw image filtering algorithm to increase available images, thereby expanding the completeness. It improves OTSU thresholding by replacing anomaly thresholds with the median value, thus enhancing the accuracy of SWS datasets. Gaps caused by Landsat7 ETM + SLC-off are respired with the random forest algorithm and morphological operations. The results show that this novel framework effectively expands the long-term series of SWS for three surface water bodies with distinct geomorphological patterns. The evaluation of confusion matrices suggests the good performance of extracting surface water, with the overall accuracy ranging from 0.96 to 0.97, and user's accuracy between 0.96 and 0.98, producer's accuracy ranging from 0.83 to 0.89, and Matthews correlation coefficient ranging from 0.87 to 0.9 for several spectral water indices (NDWI, MNDWI, ANNDWI, and AWEI). Compared with the Global Reservoirs Surface Area Dynamics (GRSAD) dataset, our constructed datasets promote greater completeness of SWS datasets by 27.01%-91.89% for the selected water bodies. The proposed framework for detecting SWS shows good potential in enlarging and completing long-term global-scale SWS datasets, capable of supporting assessments of surface-water-related environmental management and disaster prevention.


Assuntos
Monitoramento Ambiental , Água , Monitoramento Ambiental/métodos , Imagens de Satélites , Meio Ambiente , Algoritmos
2.
Environ Sci Pollut Res Int ; 31(5): 8082-8098, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38175517

RESUMO

The Yarlung Tsangpo River Basin is characterized by its intricate topography and a significant presence of erosive materials. These often coincide with heavy localized precipitation, resulting in pronounced hydraulic erosion and geological hazards in mountainous regions. To tackle this challenge, we integrated the RUSLE-TLSD (Revised Universal Soil Loss Equation-Transportation-limited sediment delivery) model with InSAR (Interferometric Synthetic Aperture Radar) data, aiming to explore the sediment transport process and pinpoint hazard-prone sites within mountainous small watershed. The RUSLE-TLSD model aids in evaluating multi-year sediment transport dynamics in mountainous zones. And, the InSAR data precisely delineates changes in sediment scouring and siltation at sites vulnerable to hazards. Our research estimates that the potential average soil erosion within the watershed stands at 52.33 t/(hm2 a), with a net soil erosion of 0.69 t/(hm2 a), the sediment transport pathways manifest within the watershed's gullies and channels. Around 4.32% of the watershed area undergoes sedimentation, predominantly at the base of slopes and within channels. Notably, areas (d) and (e) emerge as the most susceptible to disasters within the watershed. Further analysis of the InSAR data highlighted four regions in the typical area (e) from 2017 that are either sedimentation- or erosion-prone, referred to as "hotspots." Among them, R1 exhibits a strong interplay between water and sediment, rendering it highly sensitive to environmental factors. In contrast, R4, characterized by a sharp bend in siltation, remains relatively impervious to external elements. The NDVI (normalized difference vegetation index) stands out as the pivotal determinant influencing sediment transport within the watershed, exerting a pronounced impact on the outlet section, especially in spring. By employing this approach, we gained a deeper understanding of sediment transport mechanisms and potential hazards in small watershed in uninformative mountainous areas. This study furnishes a robust scientific framework beneficial for erosion mitigation and disaster surveillance in mountainous watersheds.


Assuntos
Monitoramento Ambiental , Rios , Monitoramento Ambiental/métodos , Solo , China , Estações do Ano
3.
Front Cell Neurosci ; 11: 281, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29033786

RESUMO

ß-Amyloid protein (Aß) is thought to cause neuronal loss in Alzheimer's disease (AD). Aß treatment promotes the re-activation of a mitotic cycle and induces rapid apoptotic death of neurons. However, the signaling pathways mediating cell-cycle activation during neuron apoptosis have not been determined. We find that Wnt5a acts as a mediator of cortical neuron survival, and Aß42 promotes cortical neuron apoptosis by downregulating the expression of Wnt5a. Cell-cycle activation is mediated by the reduced inhibitory effect of Wnt5a in Aß42 treated cortical neurons. Furthermore, Wnt5a signals through the non-canonical Wnt/Ca2+ pathway to suppress cyclin D1 expression and negatively regulate neuronal cell-cycle activation in a cell-autonomous manner. Together, aberrant downregulation of Wnt5a signaling is a crucial step during Aß42 induced cortical neuron apoptosis and might contribute to AD-related neurodegeneration.

4.
Neuropsychiatr Dis Treat ; 12: 3145-3152, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28003750

RESUMO

BACKGROUND: Alzheimer's disease (AD) is considered to be a neurodegenerative disorder that is characterized by increased oxidative stress. Medicinal plants, with their antioxidant properties, have been used to cure several human diseases. The aim of the current study was to explore the protective and therapeutic effect of baicalein on AD-induced rats. MATERIALS AND METHODS: Swiss Wistar rats were used in the study. The rats were divided into five groups. Group I: normal control group treated with water; Group II: disease control treated with AlCl3 to induce the mimicking AD for 4 successive weeks (SW); Group III: normal control group treated with baicalein (5 mg/kg) for 2 SW followed by combination of baicalein and AlCl3 for 4 SW; Group IV: normal control group treated with baicalein (10 mg/kg) for 2 SW followed by combination of baicalein and AlCl3 for 4 SW; Group V: normal control group treated with rivastigmine (0.3 mg/kg) for 2 SW followed by combination of rivastigmine and AlCl3 for 4 SW. Moreover, the therapeutic groups are as follows: Group VI: AD disease control treated with AlCl3 for 4 SW and serving as the therapeutic positive group; Group VII: AD disease control + baicalein (5 mg/kg) for 12 SW; Group VIII: AD disease control + baicalein (10 mg/kg) for 12 SW; Group IX: AD disease control + rivastigmine (0.3 mg/kg) for 12 SW. Behavioral test, T-maze, and rotarod test were also performed before and after the treatment. At the end of the experimental study, all the rats were sacrificed and their brains were removed and divided into two portions. The first portion was homogenated for estimating the level of acetylcholinesterase (AchE) and acetylcholine (Ach). Another portion was used for histopathological evaluation. RESULTS: The current investigation showed that baicalein significantly reduced the duration of revolving on the rotarod, cage activity, and T-maze activity in a dose-dependent manner compared with the AD control group rats. It also altered the AchE and Ach levels in the brain homogenates. The histopathology study also provides strength to the protective effect of baicalein. CONCLUSION: The current study showed that baicalein significantly (P<0.05) improved the biochemical and histopathological condition of AD in rats.

5.
Chin Med J (Engl) ; 126(18): 3439-45, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24034086

RESUMO

BACKGROUND: Our previous study had demonstrated that ulinastatin (UTI) had a neuroprotective effect in experimental autoimmune encephalomyelitis (EAE). Methylprednisolone has been recommended to be a standard drug in multiple sclerosis (MS) therapies. The present study was to investigate the protective effects of UTI combined methylprednisolone in EAE. METHODS: Mice were divided into a UTI treatment group, a methylprednisolone treatment group, a combined treatment group with UTI and methylprednisolone, a normal saline treatment group, and a normal control group. EAE mice were induced in groups receiving different combined treatments, or respective monotherapies. Demyelination was evaluated by Solochrome cyanin staining. 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNP)/ myelin basic protein (MBP)/ the precursor form of nerve growth factor (proNGF)/p75/ inducible nitric oxide synthase (iNOS) proteins in cerebral cortex of EAE were detected by Western blotting. RESULTS: The combined treatment group had a lower clinical score (0.61 ± 0.06) and demyelinating score (1.33 ± 0.33) than the groups with normal saline (clinical score: 1.39 ± 0.08, P < 0.001; demyelinating score: 2.75 ± 0.49, P < 0.05) or monotheraphies. Compared with the saline treated EAE group, UTI combined methylprednisolone significantly increased expressions of CNP (1.14 ± 0.06 vs. 0.65 ± 0.04, P < 0.001), MBP (1.28 ± 0.14 vs. 0.44 ± 0.17, P < 0.001), and decreased expressions of proNGF (1.08 ± 0.10 vs. 2.32 ± 0.12, P < 0.001), p75 (1.13 ± 0.13 vs. 2.33 ± 0.17, P < 0.001), and iNOS (1.05 ± 0.31 vs. 2.17 ± 0.13, P < 0.001) proteins in EAE. Furthermore, UTI combined methylprednisolone could significantly upregulate MBP (1.28 ± 0.14 vs. 1.01 ± 0.15, P < 0.05) expression and downregulate iNOS (1.05 ± 0.31 vs. 1.35 ± 0.14, P < 0.05) expression compared to methylprednisolone treatment EAE group. And proNGF expression was significantly lower in combined treatment (1.08 ± 0.10) than that in UTI (1.51 ± 0.24, P < 0.05) or methylprednisolone (1.31 ± 0.04, P < 0.05) treatment group. CONCLUSION: Combination treatment of UTI with methylprednisolone was shown to protect EAE, suggesting that combination therapy is a potential novel treatment in MS.


Assuntos
Encefalomielite Autoimune Experimental/tratamento farmacológico , Glicoproteínas/uso terapêutico , Metilprednisolona/uso terapêutico , Animais , Combinação de Medicamentos , Feminino , Glicoproteínas/administração & dosagem , Metilprednisolona/administração & dosagem , Camundongos , Camundongos Endogâmicos C57BL , Esclerose Múltipla/tratamento farmacológico
6.
Sheng Wu Gong Cheng Xue Bao ; 19(1): 30-4, 2003 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-15969032

RESUMO

By the method of single preimplantation embryos differential display polymerase chain reaction (SPEDDRT-PCR), 25 reprogramming cDNA fragments were obtained from single 2-cell, 8-cell embryos and blastula. After cloning and sequencing, five of them were identified by reverse-Northern and characterized with stage-specific expression during reconstructed embryo development. This results will help to isolate full length reprogramming genes and study their function during embryonic development.


Assuntos
Blastocisto/metabolismo , Desenvolvimento Embrionário/fisiologia , Animais , Blastocisto/fisiologia , Northern Blotting , Embrião de Mamíferos/metabolismo , Desenvolvimento Embrionário/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento/genética , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Reação em Cadeia da Polimerase , Gravidez , Coelhos
7.
Dev Growth Differ ; 45(5-6): 543-51, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14706078

RESUMO

Lack of or abnormal expression of developmentally important genes is believed to hamper early development of the nuclear transfer (NT) embryo. To identify stage-specific genes in rabbit NT embryo development, mRNA differential display was used to compare the mRNA content of rabbit NT embryos at different developmental stages, from Metaphase II oocytes to 8-16-cell stage embryos. Thirty-four zygotic transcripts, which abruptly appeared at the 8-16-cell stage in rabbit NT embryos, were isolated; 11 of these were potential novel genes with no matches in the current databases. Of the remaining 23, 12 were matched with established sequence tags with functions uncharacterized and the other 11 were homologous to those in the European Molecular Biology Laboratory (EMBL) and GenBank databases. The differential expression of eight of the 34 amplicons were confirmed by reverse Northern blotting, and four positive clones were validated. Previous studies and present data indicated that these three genes were probably related to preimplantation rabbit embryo development.


Assuntos
Embrião de Mamíferos/fisiologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Técnicas Genéticas , Animais , Sequência de Bases , Blastocisto , Northern Blotting , Núcleo Celular/metabolismo , DNA Complementar/metabolismo , Bases de Dados como Assunto , Desenvolvimento Embrionário e Fetal , Feminino , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , RNA Mensageiro/metabolismo , Coelhos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência do Ácido Nucleico , Fatores de Tempo
8.
Sheng Wu Gong Cheng Xue Bao ; 18(1): 79-83, 2002 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-11977606

RESUMO

This study was carried out to examine the effect of different donor cell type and micro-manipulation on the development of reconstituted embryos. Cultured mural cumulus cells or fibroblast cells from an adult transgenic goat expressing human erythropoietin(rhEPO) were used as the donor cells in nuclear transfer experiments. The reconstituted eggs were generated by transferring fibroblast cells or cumulus cells into the perivitelline space of enucleated M II oocytes and then followed by electrofusion and activation. After 6 days' incubation in vivo, the reconstructed embryos developed into morulae or blastocysts were transferred into 6 foster recipients. Two of the foster-mothers were pregnant and gave birth to two offspring, which were derived from the fibroblast cell and cumulus cell, respectively. Fingerprint analysis showed that the PCR-RFLP patterns of the two offspring were identical to that of donor goats. PCR results indicated that these cloned goats carried hEPO gene as same as their donor cells.


Assuntos
Clonagem de Organismos , Fibroblastos/citologia , Cabras/embriologia , Técnicas de Transferência Nuclear , Oócitos/citologia , Animais , Animais Geneticamente Modificados/genética , Fusão Celular/métodos , Transferência Embrionária/tendências , Eritropoetina/biossíntese , Eritropoetina/genética , Cabras/genética , Humanos , Microinjeções/métodos
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