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991.
In Vitro Cellular & Developmental Biology - Plant - Calycosin-7-O-β-D-glucoside (CG), a methoxylated isoflavonoid in Astragalus membranaceus Fisch. (Bunge), has a wide range of biological...  相似文献   
992.
In the present study, a new hepatic tissue‐origin cell line from European eel Anguilla anguilla has been developed and characterized. This cell line designated EL has been maintained in Leibovitz L‐15 supplemented with 10% fetal bovine serum over 72 months, and subcultured more than 90 times. The EL cell line consisted predominantly of fibroblast‐like cells, which could survive over 100 days in vitro, and could grow at 15–32°C. The optimum temperature for growth was 27°C. The chromosome analysis revealed a modal diploid karyotype of 2n = 38. The origin of this cell line was confirmed by the 18S recombinant (r)RNA sequencing. The susceptibility test indicated significant cytopathic effects in the EL cells with regard to the Rana grylio virus and the Herpesvirus anguillae. The viral replication was confirmed by transmission electron microscopy and polymerase chain reaction analysis. Following poly (I:C) exposure, the expression levels of the immune‐related molecules interferon regulatory factor‐7 (irf7) and transforming growth factor‐β (TGF‐β) were downregulated in EL cells, whereas the expression levels of the rf3 and the cytochrome P450 (CYP450) were upregulated. All four genes were significantly upregulated following inflammation by lipopolysaccharide (LPS). These data suggested the application of EL cell line for viral identification, as well as for immunodiagnosis and pharmacological targeting.  相似文献   
993.
To investigate the roles of tripartite motif containing 52 (TRIM52) in human hepatic fibrosis in vitro, human hepatic stellate cell line LX‐2 cells were transfected with hepatitis B virus (HBV) replicon to establish HBV‐induced fibrosis in LX‐2 cells, and then treated with small interfering RNA‐mediated knockdown of TRIM52 (siTRIM52). LX‐2 cells without HBV replicon transfection were treated with lentiviruses‐mediated overexpression of TRIM52 and phosphatase magnesium dependent 1A (PPM1A). Fibrosis response of LX‐2 cells were assessed by the production of hydroxyproline (Hyp) and collagen I/III, as well as protein levels of α‐smooth muscle actin (α‐SMA). PPM1A and phosphorylated (p)‐Smad2/3 were measured to assess the mechanism. The correlation between TRIM52 and PPM1A was determined using co‐immunoprecipitation, and whether and how TRIM52 regulated the degradation of PPM1A were determined by ubiquitination assay. Our data confirmed HBV‐induced fibrogenesis of LX‐2 cells, as evidenced by significant increase in Hyp and collagen I/III and α‐SMA, which was associated with reduction of PPM1A and elevation of transforming growth factor‐β (TGF‐β), p‐Smad2/3, and p‐Smad3L. However, those changes induced by HBV were significantly attenuated with additional siTRIM52 treatment. Similar to HBV, overexpression of TRIM52 exerted promoted effect in the fibrosis of LX‐2 cells. Interestingly, TRIM52 induced the fibrogenesis of LX‐2 cells and the activation of TGF‐β/Smad pathway were significantly reversed by PPM1A overexpression. Furthermore, our data confirmed TRIM52 as a deubiquitinase that influenced the accumulation of PPM1A protein, and subsequently regulated the fibrogenesis of LX‐2 cells. TRIM52 was a fibrosis promoter in hepatic fibrosis in vitro, likely through PPM1A‐mediated TGF‐β/Smad pathway.  相似文献   
994.
Revegetation represents an effective measure for preventing soil erosion on the Loess Plateau. However, the effects of revegetation‐induced changes in soil and root properties on soil resistance to concentrated flow erosion (SRC) remain unclear. This study sampled soils and roots across a 25‐year chronosequence from farmland to grasslands of different ages (3, 7, 10, 18, and 25 years) to quantify variations in soil and root properties (soil bulk density, SBD; soil disintegration rate, SDR; saturated hydraulic conductivity, SHC; organic matter content, OMC; water‐stable aggregate, WSA; mean weight diameter, MWD; root mass density, RMD; root length density, RLD; and root surface area density, RSAD) and their effects on SRC. Farmland and grassland SRCs were obtained using a hydraulic flume. Soil properties and root density gradually improved with restoration time. In terms of the comprehensive soil property index calculated via principal component analysis, grassland values were 0.66 to 1.94 times greater than farmland values. Grassland SRCs increased and gradually stabilized (>18 years) over time and were 1.60 to 8.26 times greater than farmland SRC. SRC improvement was significantly related to increases in OMC, SHC, WSA, and MWD and decreases in SBD and SDR over time. SRC was effectively simulated by the Hill curve of RMD, RLD, and RSAD. SDR, SHC, and RMD (0.5–1.0 mm) affected SRC the most. This study scientifically describes how revegetation improves soil quality and soil resistance to flow erosion, and suggests that vegetations rich in 0.5–1.0 mm roots should be preferred during revegetation.  相似文献   
995.
Yang  X. S.  Chen  Z. H.  Wang  B.  Liu  S. Q. 《Plasma Physics Reports》2020,46(8):815-822
Plasma Physics Reports - Modulational collapse of a wave pulse in a complex nonlinear plasma described by a complex nonlinear Schrödinger equation (CNSE) including the effects of viscous...  相似文献   
996.
Idiopathic pulmonary fibrosis (IPF) is a progressive disease characterized by excessive deposition of extracellular matrix (ECM) and chronic inflammation with limited therapeutic options. Psoralen, a major active component extracted from Psoralea corylifolia L. seed, has several biological effects. However, the role of psoralen in IPF is still unclear. Here, we hypothesized that psoralen played an essential role in IPF in the inhibition of fibroblast proliferation and inflammatory response. A murine model of IPF was established by injecting bleomycin (BLM) intratracheally, and psoralen was administered for 14 days from the 7th to 21st day after BLM injection. Our results demonstrated that psoralen treatment reduced body weight loss and improved the survival rate of mice with IPF. Histological and immunofluorescent examination showed that psoralen alleviated BLM‐induced lung parenchymal inflammatory and fibrotic alteration. Furthermore, psoralen inhibited proliferation and collagen synthesis of mouse fibroblasts and partially reversed BLM‐induced expression of α‐smooth muscle actin at both the tissue and cell level. Moreover, psoralen decreased the expression of transforming growth factor‐β1, interleukin‐1β, and tumor necrosis factor‐α in the lungs of BLM‐stimulated mice. Our results reveale for the first time that psoralen exerts therapeutic effects against IPF in a BLM‐induced murine model.  相似文献   
997.
Yang  R.  Yu  G.  Li  H.  Li  X.  Mu  C. 《Russian Journal of Plant Physiology》2020,67(2):231-241
Russian Journal of Plant Physiology - Organisms can produce heat shock proteins (HSPs) in response to elevated temperatures and other abiotic stresses. However, the function of HSPs, including...  相似文献   
998.
Guo  K. B.  Qiao  G.  Qiu  Z. L.  Wen  Z.  Yang  H.  Wen  X. P. 《Russian Journal of Plant Physiology》2020,67(1):94-102
Russian Journal of Plant Physiology - Attempts had been made to provide evidences insight into the pattern and physiological mechanism of sweet cherry fruit dropping. However, the fruit abscission...  相似文献   
999.
Yang  H. Y.  Dong  S. S.  Zhang  C. H.  Wu  W. L.  Lyu  L. F.  Li  W. L. 《Russian Journal of Plant Physiology》2020,67(1):76-84
Russian Journal of Plant Physiology - Tocopherol (vitamin E) is widely recognized as a cellular antioxidant and can prevent oxidative damage during seed quiescence and dormancy in all angiosperms....  相似文献   
1000.
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