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1.
Ying Yong Sheng Tai Xue Bao ; 30(10): 3491-3500, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31621236

RESUMO

The dynamic simulation of cucumber growth and development in sunlight greenhouse can provide technical support for the intelligent management of cucumber production. According to the cucumber response characteristics to light and temperature, the cucumber development module based on the algorithm of clock model was established by using data from four-stage experiment with 'Jinyou 35' as experiment variety in two years. Based on the relationship between the leaf growth and key meteorological factors (temperature and radiation), leaf area index (LAI) module was established with the accumulated product of thermal effectiveness and photosynthetically active radiation (TEP) as independent variables. The simulation module of cucumber dry matter production was established by taking into consideration the double integral of LAI and daily length in photosynthesis per unit leaf area as well as the respiratory expenditure of different organs. Combined with water content of organs, fresh weight simulation module of cucumber organs was constructed. The whole cucumber development and growth simulation model in greenhouse was built based on each sub-module. The model parameters were calibrated and determined. The results showed that root mean square error (RMSE) of simulated values and observed values of four deve-lopment stages (from transplanting date to stretch tendril, to initial flowering, to early harvested and to uprooting), was 3.9-10.5 d. The normalized root mean square error (nRMSE) was 6.5%-28.6%. The coincidence index (D) was 0.79-0.97. The relationship between LAI and TEP was the regression of 'S' type curve. The RMSE of simulated and observed LAI values was 0.19. The nRMSE was 17.2%. The D value was 0.90. The RMSE of dry weight of root, stem, leaf, flower and fruit of the simulated values and observed values were 0.39-8.94 g·m-2. The nRMSE were 10.9%-17.7%. The D values were all above 0.98. The growth and development model of cucumber could accurately simulate the key development period of cucumber, leaf area and the dry and fresh weight of various organs and quantify the growth and development of cucumber in sunlight greenhouse.


Assuntos
Cucumis sativus , Crescimento e Desenvolvimento , Fotossíntese , Folhas de Planta , Luz Solar
2.
Ying Yong Sheng Tai Xue Bao ; 27(11): 3585-3592, 2016 Nov 18.
Artigo em Chinês | MEDLINE | ID: mdl-29696856

RESUMO

The suitability of four popular empirical and semi-empirical stomatal conductance models (Jarvis model, Ball-Berry model, Leuning model and Medlyn model) was evaluated based on para-llel observation data of leaf stomatal conductance, leaf net photosynthetic rate and meteorological factors during the vigorous growing period of potato and oil sunflower at Wuchuan experimental station in agro-pastoral ecotone in North China. It was found that there was a significant linear relationship between leaf stomatal conductance and leaf net photosynthetic rate for potato, whereas the linear relationship appeared weaker for oil sunflower. The results of model evaluation showed that Ball-Berry model performed best in simulating leaf stomatal conductance of potato, followed by Leuning model and Medlyn model, while Jarvis model was the last in the performance rating. The root-mean-square error (RMSE) was 0.0331, 0.0371, 0.0456 and 0.0794 mol·m-2·s-1, the normalized root-mean-square error (NRMSE) was 26.8%, 30.0%, 36.9% and 64.3%, and R-squared (R2) was 0.96, 0.61, 0.91 and 0.88 between simulated and observed leaf stomatal conductance of potato for Ball-Berry model, Leuning model, Medlyn model and Jarvis model, respectively. For leaf stomatal conductance of oil sunflower, Jarvis model performed slightly better than Leuning model, Ball-Berry model and Medlyn model. RMSE was 0.2221, 0.2534, 0.2547 and 0.2758 mol·m-2·s-1, NRMSE was 40.3%, 46.0%, 46.2% and 50.1%, and R2 was 0.38, 0.22, 0.23 and 0.20 between simulated and observed leaf stomatal conductance of oil sunflower for Jarvis model, Leuning model, Ball-Berry model and Medlyn model, respectively. The path analysis was conducted to identify effects of specific meteorological factors on leaf stomatal conductance. The diurnal variation of leaf stomatal conductance was principally affected by vapour pressure saturation deficit for both potato and oil sunflower. The model evaluation suggested that the stomatal conductance models for oil sunflower are to be improved in further research.


Assuntos
Helianthus/fisiologia , Modelos Biológicos , Estômatos de Plantas/fisiologia , Solanum tuberosum/fisiologia , China , Fotossíntese , Folhas de Planta/fisiologia
3.
Artigo em Inglês | MEDLINE | ID: mdl-21860655

RESUMO

Objective. This study was intended to evaluate the efficacy and safety of ligustrazine injection for chronic pulmonary heart disease (CPHD). Method. Randomized controlled trials (RCTs) of clinical therapeutic studies on CPHD when using ligustrazine injection were included. Searches were applied to the following electronic databases: the PubMed, the Cochrane Library, EMBASE, CBM, and AMED. No language restriction was used. All trials included were analyzed according to the criteria of the Cochrane Handbook. Review Manager 5.0 software was used for data analysis. Result. 34 RCTs with low methodological quality were included. Compared to conventional medicine treatment alone, ligustrazine injection plus conventional medicine treatment showed improvement in New York Heart Association classification of clinical status (Odds ratio 0.22; 95% CI 0.17 to 0.28) and depression of pulmonary artery hypertension (weighted mean difference -4.77; 95% CI -5.85 to -3.68). Three studies had reported adverse events. No serious adverse effects were reported. Conclusion. While there is some evidence that suggests potential effectiveness of ligustrazine injection for CPHD, the results were limited by the methodological flaws of the studies. High quality studies are needed to provide clear evidence for the future use of ligustrazine injection.

4.
Cell Commun Adhes ; 14(1): 21-31, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17453828

RESUMO

Melanoma-associated antigen family protein-D1 (MAGE-D1) is a recently identified p75 neurotrophin receptor intracellular binding protein and functions as an adaptor that mediates multiple signaling pathways, including Dlx/Msx-mediated transcription. Here, a new regulatory function for MAGE-D1 in tumor cell motility and adhesion to endothelium is described. MAGE-D1 over-expression suppressed HeLa cell and BEL7402 cell migration, invasion, and adhesion to the monolayer of ECV304 cells. We also report that MAGE-D1 over-expression disrupted actin cytoskeleton rearrangement induced by hypoxia and down-regulated hypoxia inducible factor 1-dependent luciferase gene expression. These findings provide new insight into the ability of MAGE-D1 to suppress the motility and adhesion response of tumor cells by interfering with actin cytoskeleton reorganization and hypoxia inducible factor 1-dependent gene expression.


Assuntos
Actinas/metabolismo , Antígenos de Neoplasias/metabolismo , Movimento Celular , Endotélio/patologia , Proteínas de Neoplasias/metabolismo , Neoplasias/metabolismo , Neoplasias/patologia , Actinas/química , Adenoviridae/genética , Western Blotting , Adesão Celular , Hipóxia Celular , Linhagem Celular Tumoral , Proliferação de Células , Citoesqueleto/metabolismo , Regulação Neoplásica da Expressão Gênica , Genes Reporter , Células HeLa , Humanos , Fator 1 Induzível por Hipóxia/genética , Invasividade Neoplásica , Pseudópodes/metabolismo , Cicatrização
5.
Mol Cell Biochem ; 300(1-2): 89-99, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17149546

RESUMO

MAGE-D1 is a member of the MAGE family of proteins, and functions as an adaptor that mediates multiple signaling pathways. The current study for the first time provides evidence for a role of MAGE-D1 in the negative regulation of angiogenic activity in vitro and in vivo models. Our findings showed that MAGE-D1 over-expression significantly suppressed the angiogenic key events such as endothelial cell migration and invasion, adhesion on collagen I substrate, and in vitro differentiation into tube-like structures under both normoxic and hypoxic conditions. MAGE-D1 over-expression also inhibited in vivo angiogenesis in Matrigel plugs that were implanted subcutaneously in mice. With further experiments, we revealed that MAGE-D1 over-expression disrupted actin cytoskeleton organization and lamellipodia formation, and down-regulated HIF-1-dependent gene expression in endothelial cells under hypoxic conditions. These findings demonstrate a new function of MAGE-D1 in the regulation of angiogenesis and provide new insight into the ability of MAGE-D1 to suppress the growth and angiogenic response of endothelial cells by interfering with HIF-1-dependent gene expression, and actin cytoskeleton reorganization, suggesting that MAGE-D1 might be a novel inhibitor of angiogenesis in vitro and in vivo.


Assuntos
Adenoviridae/fisiologia , Antígenos de Neoplasias/metabolismo , Proteínas de Neoplasias/metabolismo , Neovascularização Fisiológica , Actinas/metabolismo , Adesão Celular , Movimento Celular , Células Cultivadas , Colágeno/metabolismo , Citoesqueleto/metabolismo , Combinação de Medicamentos , Células Endoteliais/citologia , Células Endoteliais/virologia , Regulação da Expressão Gênica , Genes Reporter , Humanos , Fator 1 Induzível por Hipóxia/genética , Laminina/metabolismo , Proteoglicanas/metabolismo , Pseudópodes/metabolismo
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