Objective To investigate the activation and role of signal transduction pathway of epidermal growth factor (EGF)-epidermal growth factor receptor (EGFR)-mitogen activated protein kinase (MAPK) in proliferation of human retinal pigment epithelial (RPE) cells. Methods Human RPE cells were stimulated with 0.1%，10% foetal calfserum (FCS) and EGF(0.1, 1, 10, 50 and 100 ng/ml)in 0.1% FCS Dulbeco′s modified Eagle′s medium (DMEM) and in 10% FCS DMEM for 3 days, respectively. Immunohistochemical staining and in situ hybridization were used to observe the expressions of EGFR protein and EGFR mRNA，respectively. Activation of MAPK was detected by immunohistochemical method with specific anti-phosphorylated ERK 1/2 antibody. Results The optimal concentrations of EGF were 10 ng/ml in 0.1% FCS DMEM and 1 ng/ml in 10% FCS DMEM. After 3 days of stimulation with EGF, phosphorylated ERK 1/2 staining was detectable in nucleus of RPE cells, whereas cells presented immunostaining for phosphorylated ERK 1/2 in the cytoplasm before stimulation. Conclusions EGF may improve the expression of EGFR protein and EGFR mRNA of RPE cells, and induced MAPK nuclear translocation in a concentration-dependent manner. EGF-EGFR-MAPK signal transduction pathway may play a key role in RPE cells proliferation, and serum exerts an important acceclerating function in the process. (Chin J Ocul Fundus Dis，2004，20：67-132)
The brain-computer interface (BCI) based on motor imagery electroencephalography (EEG) shows great potential in neurorehabilitation due to its non-invasive nature and ease of use. However, motor imagery EEG signals have low signal-to-noise ratios and spatiotemporal resolutions, leading to low decoding recognition rates with traditional neural networks. To address this, this paper proposed a three-dimensional (3D) convolutional neural network (CNN) method that learns spatial-frequency feature maps, using Welch method to calculate the power spectrum of EEG frequency bands, converted time-series EEG into a brain topographical map with spatial-frequency information. A 3D network with one-dimensional and two-dimensional convolutional layers was designed to effectively learn these features. Comparative experiments demonstrated that the average decoding recognition rate reached 86.89%, outperforming traditional methods and validating the effectiveness of this approach in motor imagery EEG decoding.
Extracellular vesicles (EVs), defined as cell-secreted nanoscale vesicles that carry bioactive molecules, have emerged as a promising therapeutic strategy in tumor and tissue regeneration. Their potential in repairing intervertebral disc degeneration (IDD) through multidimensional regulatory mechanisms is a rapidly advancing field of research. This paper provided an overview of the mechanisms of EVs in IDD repair, thoroughly reviewed recent literature on EVs for IDD, domestically and internationally, and summarized their therapeutic mechanisms. In IDD repair, EVs could act through different mechanisms at the molecular, cellular, and tissue levels. At the molecular level, EVs could treat IDD by inhibiting inflammatory reactions, suppressing oxidative stress, and regulating the synthesis and decomposition of extracellular matrix. At the cellular level, EVs could treat IDD by inhibiting cellular pyroptosis, ferroptosis, and apoptosis and promoting cell proliferation and differentiation. At the tissue level, EVs could treat IDD by inhibiting neovascularization. EVs have a strong potential for clinical application in the treatment of IDD and deserve more profound study.
To summarize Notch, basic hel ix-loop-hel ix (bHLH) and Wnt gene signal transduction pathways in the process of differentiation and development of neural stem cells. Methods The l iterature on the gene signal transduction pathway in the process of differentiation and development of neural stem cells was searched and then summarized and analyzed. Results The formation of Nervous System resulted from common actions of multi-signal transduction pathways. There may exist a fixed threshold in the compl icated selective system among Notch, bHLH and Wnt gene signal transduction pathways. Conclusion At present, the specific gene signal transduction pathway of multi pl ication and differentiation of neural stem cells is still unclear.
Endometriosis (EM) is a common benign gynecological disease with complex pathogenesis and lack of unified understanding. In recent years, the theory of stem/progenitor cells has gradually been recognized by scholars. The presence of stem/progenitor cells in the endometrium and researchers’ understanding of stem/progenitor cell specific markers has been further developed, which is of great significance for sorting stem/progenitor cells and further elucidating their roles in the pathogenesis of EM. At present, more endometrial stem cell signaling pathways have been studied including Wnt, Hedgehog, Notch, phosphatidylinositol-3-kinase/protein kinase B, Smad/connective tissue growth factor, CXCL12/CXCR4, etc. These signaling pathways can regulate stem cell involvement in the pathogenesis of EM. Exploring how signaling pathways to regulate stem cell involvement in the pathogenesis of EM can help elucidate the specific pathogenesis of EM and provide new directions for its treatment. This paper will summarize them.
ObjectiveTo observe the regulation of PTB-associated splicing factor (PSF) exerts on phosphatidylinositol 3 kinase (PI3K)/Akt signaling pathway in cultured retinal pigment epithelial (RPE) cells. MethodsARPE-19 RPE cells were divided into five groups including PSF overexpression (0.25, 0.50, 1.00 μg of pEGFP-C2-PSF plasmid DNA), PSF overexpression control (pEGFP-C2 empty vector DNA), PSF inhibition (0.25, 0.50, 1.00 μg of pGenesil-PSF-RNAi plasmid DNA), PSF inhibition control (pGenesil-scramble-siRNA empty vector) and sham transfected group (treated with lipofactamine 2000 reagent, but without adding plasmid DNA) groups. After transfecting with plasmid DNA, the cells were stimulated with insulin-like growth factor-1 (IGF-1). IGF-1-stimulated ARPE-19 cells were also treated with Wortmannin and /or PSF over-expression. WST-1 assay was used to detect the proliferation rates, the VEGF mRNA levels were analyzed using real time polymerase chain reaction (PCR), the levels of phosphorylation Akt and total Akt expression were measured by western blotting. ResultsAfter IGF-1 stimulation, the difference of the cell proliferation rates between PSF overexpression group, PSF overexpression control group and sham transfected group was statistically significant (F=29.728, P<0.05). The difference of the cell proliferation rates between PSF inhibition group, PSF inhibition control group and sham transfected was also statistically significant (F=14.121, P<0.05). Compared with control group, the VEGF mRNA levels was decreased in PSF overexpression group (P=0.000 3), but increased in PSF low expression group (P=0.030 9). Furthermore, overexpression of PSF could down-regulate the activation of pAkt after IGF-1 stimulation. When combined with Wortmannin treatment, the VEGF mRNA levels in PSF overexpression group was significantly lower than the control group (P<0.05). ConclusionsAfter IGF-1 treatment, PSF plays a role in suppressing the proliferation and VEGF expression in RPE cells by inactivating PI3K/Akt signaling pathway.
ObjectiveTo investigate the associations of signal transducers and activators of transcription 6 (STAT6) gene polymorphisms with susceptibility to tuberculosis in western Chinese Han population.MethodsA total of 900 tuberculosis patients and 1 534 healthy controls of West China Hospital of Sichuan University were enrolled from January 2014 to February 2016. Improved multiplex ligation detection reaction method was used to detect four polymorphisms (rs1059513, rs73118432, rs841718, and rs10783813) of STAT6 gene. The allelic frequencies, genetic types, and different genetic models were analyzed using the chi-square test and unconditional logistic regression models to evaluate the associations of STAT6 gene with tuberculosis risk.ResultsEventually, a total of 856 cases and 1 511 health controls were recruited in our study. No significant differences were observed in allele frequencies, genotype distributions, or genetic models (additive model, dominant model and recessive model) at rs1059513, rs73118432, rs841718, and rs10783813 in STAT6 gene (P>0.05). We found a strong linkage disequilibrium among rs73118432, rs841718, and rs10783813, but there was no statistical difference in haplotype frequencies between the two groups (P>0.05).ConclusionsSTAT6 gene rs73118432, rs841718, rs10783813, and rs1059513 polymorphisms might have no associations with tuberculosis susceptibility in western Chinese Han population. Further studies with larger sample sizes are needed to comfirm these results.
Objective To summarize the important role of myeloid differentiation factor 88 （MyD88） in toll like receptor （TLR） signaling pathway， and to summarize the relationship between MyD88 and relative diseases， and its potential application value. Methods Domestic and international publications online involving the role of MyD88 in TLR signaling pathway and the influence of MyD88 in some kinds of diseases in recent years were collected and reviewed. Results MyD88 was an important adapter protein， and played a connecting role in the TLR signaling pathway. It was the bottle neck of TLR signaling pathway， and could lead to the activation of many transcription factor to initiate innate immune response. It was also related to a variety of diseases. Conclusions MyD88 is the key adapter protein in TLR signaling pathway. It plays an important role in innate immunity， acquired immunity， and a variety of diseases， so it is a potential therapeutic target.
Objective To review the progress and application of peripheral nervous microelectrode. Methods The recent articles on peripheral nervous microelectrode were extensively reviewed. The classification, the progress of the peripheral nervous microelectrode and its utilizable prospect in the control of electronic prosthesis were summarized. Results The microelectrodes had favorable functions of selective stimulation and recording. It provided an information transmitting interface between the electric prosthesis and peripheral nerves. Conclusion Peripheral nervous signal is a feasible signal source to control electronic prosthesis.
ObjectiveTo summarize the therapeutic targets of pancreatic cancer (PC). MethodsThe related literatures about the therapeutic targets of PC were reviewed. ResultsPC was one of the most challenging tumor in worldwide, and was characterized as a highly aggressive disease with poor overall prognosis and a high mortality rate. The hallmark of PC was its poor response to radio-and chemo-therapy. Current chemotherapeutic regimens could not provide substantial survival benefit with a clear increase in overall survival. Recently, several new approaches which could significantly improve the clinical outcome of PC had been described, involving signal-transduction pathways, immune response, stroma reaction, and epigenetic changes. ConclusionsMany therapeutic targets are involved in the treatment of PC. As current therapies failed to significantly improve the progression and the survival of PC, new therapeutic approaches and clinical studies are strongly required.