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1.
Sci Rep ; 12(1): 11549, 2022 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-35798807

RESUMO

Accurately obtaining the spatial distribution information of fruit tree planting is of great significance to the development of fruit tree growth monitoring, disease and pest control, and yield estimation. In this study, the Sentenel-2 multispectral remote sensing imageries of different months during the growth period of the fruit trees were used as the data source, and single month vegetation indices, accumulated monthly vegetation indices (∑VIs), and difference vegetation indices between adjacent months (∆VIs) were constructed as input variables. Four conventional vegetation indices of NDVI, PSRI, GNDVI, and RVI and four improved vegetation indices of NDVIre1, NDVIre2, NDVIre3, and NDVIre4 based on the red-edge band were selected to construct a decision tree classification model combined with machine learning technology. Through the analysis of vegetation indices under different treatments and different months, combined with the attribute of Feature_importances_, the vegetation indices of different periods with high contribution were selected as input features, and the Max_depth values of the decision tree model were determined by the hyperparameter learning curve. The results have shown that when the Max_depth value of the decision tree model of the vegetation indices under the three treatments was 6, 8, and 8, the model classification was the best. The accuracy of the three vegetation index processing models on the training set were 0.8936, 0.9153, and 0.8887, and the accuracy on the test set were 0.8355, 0.7611, and 0.7940, respectively. This method could be applied to remote sensing classification of fruit trees in a large area, and could provide effective technical means for monitoring fruit tree planting areas with medium and high resolution remote sensing imageries.


Assuntos
Frutas , Tecnologia de Sensoriamento Remoto , Tecnologia de Sensoriamento Remoto/métodos
2.
J Interferon Cytokine Res ; 35(7): 569-79, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25811233

RESUMO

Smad-7 inhibited the transforming growth factor beta (TGF-ß)-induced proteoglycan synthesis in chondrocytes and completely antagonized the effect of TGF-ß on the proliferation of the cells. The aim of this study was to evaluate the contribution of Smad-7 to the pathophysiology of disc degeneration by determining the expression of Smad-7 in the degenerative intervertebral discs and its effect on the extracellular matrix metabolism of disc cells. Instability of the lumbar spine produced by imbalanced dynamic and static forces was used to induce intervertebral disc degeneration in rats. The expression of Smad-7 was assessed by the immunohistochemical method. Disc cell apoptosis was detected by in situ TUNEL staining. The effect of Smad-7 overexpression on the matrix metabolism of disc cells was analyzed in vitro by real-time polymerase chain reaction (PCR) and Western blotting. Finally, intradiscal injection of the Smad-7 overexpression lentivirus was performed to evaluate the in vivo effect of Smad-7 on disc degeneration. Radiographic and histomorphological examinations showed that lumbar disc degeneration became more and more severe in the rats with induced instability. Immunohistochemical observation demonstrated increasing protein expression of Smad-7 in the degenerative discs. A significantly positive correlation was found between Smad-7 expression and the degree of disc degeneration and between Smad-7 expression and disc cell apoptosis. Overexpression of Smad-7 in disc cells inhibited the expression of TGF-ß1, collagen type-I, collagen type-II, and aggrecan and promoted the expression of MMP-13, but did not change the expression of ADAMTS-5. The in vivo findings illustrated that intradiscal injection of lentivirus vector with Smad-7 overexpression accelerated the progress of disc degeneration. In conclusion, Smad-7 was highly expressed in the degenerative discs. Overexpression of Smad-7 weakened the protective role of TGF-ß and accelerated the progress of disc degeneration. Interference on Smad-7 might be a potential therapeutic method for the prevention and treatment of degenerative disc diseases.


Assuntos
Degeneração do Disco Intervertebral/metabolismo , Degeneração do Disco Intervertebral/patologia , Proteína Smad7/metabolismo , Animais , Western Blotting , Separação Celular , Matriz Extracelular/metabolismo , Vértebras Lombares/metabolismo , Masculino , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Transfecção
3.
Molecules ; 20(3): 4290-306, 2015 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-25756649

RESUMO

Sauromatum giganteum (Engl.) Cusimano & Hett Tuber are used in Chinese folklore medicine for treatment of neoplasms. However, the claim has not been scientifically validated. The aim of the study is to screen the antitumor bioactive fraction of Sauromatum giganteum (Engl.) Cusimano & Hett Tuber and sensitive tumor cell lines using a cytotoxicity assay in vitro and tumor transplantation method in vivo, to support its use in folk medicine. The petroleum ether fraction, chloroform fraction, ethyl acetate fraction, n-butanol fraction and water fraction were successively extracted by turn by the maceration under reflux assay. Screening of antitumor bioactive fraction and sensitive cell lines were measured by MTT assay and the serum pharmacology method, and in vivo the antitumor activities of the active fraction was evaluated by using S180 or H22 tumor-bearing mice model and Kunming mice. The active constituents of ethyl acetate fraction of Sauromatum giganteum (Engl.) Cusimano & Hett were characterized by UPLC-TOF-MS. Compared with control groups, mice serum containing ethyl acetate fraction had a inhibition effect on SMMC-7721 cell, SGC-7901 cell, MCF-7 cell, HeLa cell, A549 cell, HT-29, and MDA-MB-231, respectively, but mice serum containing other four fractions had no different with that of control group. The inhibition capabilities of mice serum containing ethyl acetate fraction on the seven cell lines in descending order is SGC-7901 > SMMC-7721 > MCF-7 > HT-29 > A549 > HeLa > MDA-MB-231. In vivo the inhibition rate of 106, 318, 954 mg/kg·d ethyl acetate fraction dry extract to sarcoma S180 is 15.22%, 26.15% and 40.24%, respectively, and life prolonging rate to hepatoma H22 is 33.61%, 40.16% and 55.74%. A total of 14 compounds were identified in the ethyl acetate fraction of Sauromatum giganteum (Engl.) Cusimano & Hett. The results of the experimental studies proved the antitumor activity of Sauromatum giganteum (Engl.) Cusimano & Hett and supported the traditional use of this plant. These data indicate the potential for the use of ethyl acetate fraction of Sauromatum giganteum (Engl.) Cusimano & Hett Tuber in tumor therapy, anti-tumor activity on cancer cell line in descending order is SGC-7901 > SMMC-7721 > MCF-7 > HT-29 > A549 > HeLa > MDA-MB-231.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Araceae/química , Proliferação de Células/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Extratos Vegetais/farmacologia , Tubérculos/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Animais , Cromatografia Líquida , Feminino , Humanos , Masculino , Camundongos , Neoplasias/metabolismo , Neoplasias/patologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Asian Pac J Cancer Prev ; 15(24): 10613-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25605148

RESUMO

BACKGROUND: Both alcohol and aqueous extracts of Sauromatum giganteum(Engl.) Cusimano and Hett, the dried root tuber of which is named Baifuzi in Chinese, have been used for folklore treatment of cancer in Northeast of China. However, little is known about which is most suitable to the cancer therapy. MATERIALS AND METHODS: Serum pharmacology and MTT assays were adopted to detect the effects of ethanol and aqueous extracts of Sauromatum giganteum(Engl.) Cusimano and Hett , prepared by heat reflux methods, on proliferation of different cancer cells. RESULTS: Cancer cells treated with medium supplemented with 10%, 20%, 40% serum(v/v) containing ethanol extract had a decline in viability, with inhibition rates of 7.69%, 21.8%, 41.9% in MCF-7 cells, 42.8%, 48.1%, 51.8% in SGC-7901 cells, 44.1%, 49.2%, 53.7% in SMMC-7721 cells, 6.8%, 15.2%, 39.8% in HepG2 cells, 7.57%, 16.3%, 36.2% in HeLa cells, 6.24%, 12.5%, 27.4% in A549 cells, and 7.20%, 17.5%, 31.3% in MDA-MB-231 cells, respectively. Viability in the aqueous extract groups was no different with that of controls. CONCLUSIONS: An ethanol extract of Sauromatum giganteum(Engl.) Cusimano and Hett inhibited the proliferation of SMMC-7721, SGC-7901 and MCF-7 cells, which supports the use of alcoholic but not aqueous extracts for control of sensive cancers, which might include hepatocarcinoma, gastric cancer and breast cancer.


Assuntos
Apoptose/efeitos dos fármacos , Araceae/química , Proliferação de Células/efeitos dos fármacos , Etanol/farmacologia , Neoplasias/patologia , Extratos Vegetais/farmacologia , Tubérculos/química , Animais , Depressores do Sistema Nervoso Central/farmacologia , Células HeLa , Células Hep G2 , Humanos , Células MCF-7 , Camundongos , Neoplasias/tratamento farmacológico , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
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