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21.

Aim of the study

Scutellaria baicalensis Georgi is a widely used medicinal herb in several Asian countries including Korea. The various medicinal properties attributed to Scutellaria baicalensis include anti-bacterial, anti-viral, anti-inflammatory and anti-cancer effects. The present study investigated the cytotoxicity of Scutellaria baicalensis water extract (SBWE) on A549 non-small-cell-lung cancer cells and the A549 expression of cyclin D1, cyclin-dependent kinase 4 (CDK4) and matrix metalloproteinase-2 (MMP-2), and the effects of SBWE on cell cycle progression, especially the G1/S phase, and on cell motility.

Materials and methods

SBWE cytotoxicity was assessed by a standard colorimetric assay utilizing 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and expression of cyclin D1 and CDK4 protein in SBWE-treated A549 cells was assessed by Western blot analysis. Flow cytometry analysis was performed to determine the effect of SBWE on A549 cell cycle progression. A549 cell MMP-2 activity was examined by zymography. Cell motility and migration was assessed by a scratch wound healing assay.

Results

SBWE was not cytotoxic. The production of Cyclin D1, CDK4 and MMP-2 activity were significantly decreased in a SBWE dose-dependent manner, with maximum inhibition occurring at SBWE concentrations of 250 μg/ml and 500 μg/ml. SBWE inhibited cell cycle progression in the G1/S phase and significantly inhibited the motility of A549 cells.

Conclusions

Cyclin D1 protein may be associated with MMP-2 activity and cell motility. Thus, SBWE promotes a strong protective effect against MMP-2 mediated metastasis and cell proliferation through the down-regulation of cyclin D1. SBWE may be a useful chemotherapeutic agent for lung cancer.  相似文献   
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Thirty male pigs were infected orally with E. coli and Salmonella typhimurium, and divided into a control group and two additive groups to determine the effect of an additive mixture on the changes in protein expression. The pigs were given a food supplemented with a natural herbal additive containing immunoglobulin yolksac (IgY) at concentrations of 0.5% or 1%. On the 1st day and after eight weeks of feeding, the body weight gain, food intake and serum GOT/GPT levels were examined. The GOT/GPT levels on the 1st day were similar in the three groups. However, after eight weeks of feeding, the GOT level was significantly lower in the additive treatment groups (0.5% and 1.0%). In addition, the changes in the spleen proteome as a response to the herbal additive were examined using two-dimensional polyacrylamide gel electrophoresis. A total of 31 differentially expressed protein spots were identified by comparing the protein profiles of the control and additive treated porcine spleens. Finally, 19 proteins were detected by MALDI-TOF/MS. Overall, the proteins detected are involved in a range of biological process, such as metabolic processes, biological processes, transport, carbohydrate metabolic processes, generation of precursors and energy. In conclusion, these results support of the hypothesis that a natural herbal additive containing IgY can affect the immune regulation system and reduce the stress of microbial infections.  相似文献   
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The study of expertise is difficult to do in a laboratory environment due to the challenge of finding people at different skill levels and the lack of time for participants to acquire mastery. In this paper, we report on two studies that analyze naturalistic gameplay data using cohort analysis to better understand how skill relates to practice and habit. Two cohorts are analyzed, each from two different games (Halo Reach and StarCraft 2). Our work follows skill progression through 7 months of Halo matches for a holistic perspective, but also explores low-level in-game habits when controlling game units in StarCraft 2. Players who played moderately frequently without long breaks were able to gain skill the most efficiently. What set the highest performers apart was their ability to gain skill more rapidly and without dips compared to other players. At the beginning of matches, top players habitually warmed up by selecting and re-selecting groups of units repeatedly in a meaningless cycle. They exhibited unique routines during their play that aided them when under pressure.  相似文献   
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Formation of specific neuronal connections often involves competition between adjacent axons, leading to stabilization of the active terminal, while retraction of the less active ones. The underlying molecular mechanisms remain unknown. We show that activity-dependent conversion of pro–brain-derived neurotrophic factor (proBDNF) to mature (m)BDNF mediates synaptic competition. Stimulation of motoneurons triggers proteolytic conversion of proBDNF to mBDNF at nerve terminals. In Xenopus nerve–muscle cocultures, in which two motoneurons innervate one myocyte, proBDNF-p75NTR signaling promotes retraction of the less active terminal, whereas mBDNF–tyrosine-related kinase B (TrkB) p75NTR (p75 neurotrophin receptor) facilitates stabilization of the active one. Thus, proBDNF and mBDNF may serve as potential “punishment” and “reward” signals for inactive and active terminals, respectively, and activity-dependent conversion of proBDNF to mBDNF may regulate synapse elimination.  相似文献   
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Evidence suggests that auranofin (AF) exhibits anticancer activity by inhibiting thioredoxin reductase (TrxR). Here, in this study, we have investigated the synergistic effects of AF and morin and their mechanism for the anticancer effects focusing on apoptosis in Hep3B human hepatocellular carcinoma cells. We assessed the anticancer activities by annexin V/PI double staining, caspase, and TrxR activity assay. Morin enhances the inhibitory effects on TrxR activity of AF as well as reducing cell viability. Annexin V/PI double staining revealed that morin/AF cotreatment induced apoptotic cell death. Morin enhances AF‐induced mitochondrial membrane potential (ΔΨm) loss and cytochrome c release. Further, morin/AF cotreatment upregulated death receptor DR4/DR5, modulated Bcl‐2 family members (upregulation of Bax and downregulation of Bcl‐2), and activated caspase‐3, ‐8, and ‐9. Morin also enhances AF‐induced reactive oxygen species (ROS) generation. The anticancer effects results from caspase‐dependent apoptosis, which was triggered via extrinsic pathway by upregulating TRAIL receptors (DR4/DR5) and enhanced via intrinsic pathway by modulating Bcl‐2 and inhibitor of apoptosis protein family members. These are related to ROS generation. In conclusion, this study provides evidence that morin can enhance the anticancer activity of AF in Hep3B human hepatocellular carcinoma cells, indicating that its combination could be an alternative treatment strategy for the hepatocellular carcinoma.  相似文献   
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The aim of this study was to determine if human decay-accelerating factor (hDAF) protects against hyperacute rejection in an ex vivo liver perfusion system using human blood. Pig livers were perfused ex vivo via the portal vein for an average of 5–6 h using a membrane oxygenator. Three groups were studied. Group I: Wild-type pig livers were alloperfused with fresh pig blood (n=5). Group II: Wild-type pig livers were xenoperfused with fresh human blood (n=5). Group III: hDAF transgenic pig livers were xenoperfused with fresh human blood (n=5). The graft ischemic time, ratio of perfusate volume to liver weight, flow rate, and perfusate hematocrit were similar in each group. The hDAF livers perfused with human blood (Group III) had a lower ALT level, less protein and albumin losses, lower bilirubin levels in the perfusate, less weight gain, and greater bile production than the wild-type livers perfused with human blood. Histology showed classic features of hyperacute rejection in Group II, including massive hemorrhage, severe vasculitits, fibrin and C5b-9 deposition, and endothelial damage within 1 h of perfusion, whereas liver histology studies in Groups I and III were near normal. IgG and IgM deposits were seen in the xenoperfused livers. Electron microscopy (EM) and immuno-EM showed loss of endothelial cells, trapping of white blood cells and platelets, and diffuse fibrin deposits in Group II only. hDAF pig livers perfused with human blood showed superior function and histology when compared with wild-type pig livers. These data suggest that (1) hyperacute rejection may contribute to the inconsistent results using wild-type pig livers for extracorporeal liver support and (2) genetically modified pigs that express hDAF may provide a better donor source than wild-type pigs for extracorporeal liver support.  相似文献   
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