Objective To study the effect of knockdown of signal transducer and activator of transcription 3 (STAT3) expression by short hairpin RNA (shRNA) on proliferation, apoptosis and invasion of human gastric cancer cell line MKN-45 in vitro . Methods Specific shRNA plasmids to STAT3 were constructed, and then transfected into MKN-45 cells by lipofectamine methods. Cells were divided into three groups: control group, psiRNA-H1 transfected group as negative group and psiRNA-H1/STAT3 transfected group. Semi-quantitative RT-PCR and Western blotting were used to detect the expression of STAT3 mRNA and protein, respectively. Proliferation and apoptosis of the transfected cells were observed by methyl thiazolyl tetrazolium (MTT) method and flow cytometry (FCM), respectively. The invasion of the transfected MKN-45 cells was measured by Boyden chamber. Results Compared with the negative control cells, semi-quantitative RT-PCR and Western blotting showed that the expressions of STAT3 mRNA and protein were down-regulated in the psiRNA-H1/STAT3 transfected group ( P ＜ 0.05) . The subcloned recombinant plasmid expressing shRNA effectively inhibited MKN-45 cell growth and proliferation while empty plasmid had no such specific effect. Cell apoptosis rate increased significantly in psiRNA-H1/STAT3 transfected group （ P ＜ 0.01）, and the invasion of MKN-45 cells was efficiently inhabited in psiRNA-H1/STAT3 transfected group as compared with control group and psiRNA-H1 transfected group( P ＜ 0.01).Conclusion Recombinant plasmid psiRNA-H1/STAT3 shRNA significantly inhibits the proliferation and invasion of MKN-45 cells and promotes their apoptosis.
ObjectiveTo investigate the effects of signaling pathway about the EGFR, MAPK, IKB/NF-κB, PI3K/Akt, WNT/beta-catenin, and the Hedgehog in development of hepatocellular carcinoma(HCC).
MethodsThe related literatures about the molecular genetic mechanism of signaling pathways were reviewed.
ResultsIn the occurrence and development of HCC, the EGFR, MAPK, IKB/NF-κB, PI3K/Akt, WNT/β-catenin, and Hedgehog signaling pathways not only interweaver with each other complexly, but also interact with each other, and some tumor markers, anticancer genes, proto-oncogenes, and miRNA may have synergistic effects for the occurrence of HCC.
ConclusionThe abnormal changes of molecular signaling pathways is a necessary condition for the occurrence and development of tumor, and there is considerable cross-talk and redundancy to many signaling pathways.
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.
Objective To probe into the roles of inositol 1, 4, 5-trisphosphate (IP3) and bcl-2 gene expression in inhabiting hepatocellular carcinoma of nude mice by quercetin. Methods Animals with hepatocellular carcinoma in quercetin group were treated with injection peritoneum of quercetin 50 mg/（kg·d ） for 3 weeks, while which in control group were treated with 0.4% DMSO of RPMI 1640 0.05 ml/（g·d）. Then the volume and the weight of tumors were measured, IP3, bcl-2 mRNA and bcl-2 protein were assayed by IP3-［3H］ Birtrak Assay, RT-PCR and Western blot respectively. Results The volume and weight of tumors in quercetin group were lower than those in control group 〔（15.8±10.1） mm3 vs. （52.3±26.5） mm3 in volume, （44.8±10.4） mg vs.（91.3±31.4） mg in weight， P＜0.01〕. Content of IP3 in quercetin group was lower than that in control group 〔（13.4±1.4） pmol/mg prot vs. （35.3±6.6） pmol/mg prot， P＜0.01〕. There was no significant difference in bcl-2 mRNA expression between quercetin group and control group 〔RI （the gray degree multiply area of bcl-2 /the gray degree multiply area of β-actin）： 0.55±0.05 vs. 0.79±0.19， P＞0.05〕， but the expression of bcl-2 protein in quercetin group was lower than that in control group (RI: 1.07±0.12 vs. 6.69±1.80, P＜0.01). Conclusion Quercetin can inhabit the growth of hepatocellular carcinoma tansplanted into liver of nude mice by reducing IP3 production and down-regulating bcl-2 gene expression.
Objective To review the latest development of the research on the selfrenwal signaling pathway and culture system in vitro of the embryonic stem cells(ESCs). Methods The recent articlesabout the selfrenewal signaling pathway and culture system in vitro of the ESCs were extensively reviewed. Results Understanding of the molecular mechanism of the selfrenewalin vitro and pluripotency of the ESCs was considered important for developing improved methods of deriving, culturing and differentiating these cells into the cells that could be successfully used in the clinical practice. Conclusion A further research is needed to elucidate the selfrenewal signaling pathway and the pluripotency of the ESCs and the culture systemin vitro forthe human ESCs remains to be further improved and developed.
OBJECTIVE: To study the effect of overexpression of truncated type II TGF-beta receptor on transforming growth factor-beta 1(TGF-beta 1) autoproduction in normal dermal fibroblasts. METHODS: In vitro cultured dermal fibroblasts were treated with recombinant human TGF-beta 1(rhTGF-beta 1) (5 ng/ml) or recombinant adenovirus containing truncated type II TGF-beta receptor gene (50 pfu/cell). Their effects on regulating gene expression of TGF-beta 1 were observed with Northern blotting. RESULTS: rhTGF-beta 1 up-regulated the gene expression of TGF-beta 1 and type I procollagen. Overexpression of truncated receptor II down-regulated the gene expression of TGF-beta 1. CONCLUSION: Overexpression of the truncated TGF-beta receptor II decreases TGF-beta 1 autoproduction via blocking TGF-beta receptor signal. The results may provided a new strategy for scar gene therapy.
Objective To investigate changes of TLR2 mRNA expression in lung of a mouse model of Chlamydia Pneumoniae pneumonitis, and to explore the possible mechanism of signal transduction. Methods Ninety-six male C3H/HeJ mice were randomly divided into four groups as follows: a control group, a model group, a SB203580 intervened group, and a pyrrolidine dithiocarbamate( PDTC) intervened group. Chlamydia Pneumoniae pneumonitis was induced by intranasally inoculated with 4. 0 ×106 IFU/mL of C. Pneumoniae per mouse in the model group and two intervened groups. Then the intervened groups were intraperitoneally injected with the p38MAPK inhibitor SB203580 and nuclear factor kappa B ( NF-κB)inhibitor PDTC, respectively. Six mice in each group were randomly killed in 1st, 4th, 7th and 14th day. The expressional changes of TLR2 mRNA in the mice lung tissue were measured by semi-quantitative RT-PCR. The concentrations of TNF-α in the lung homogenate were measured by ELISA. Results TLR2 mRNA expression in the lung tissue significantly increased after C. Pneumoniae infection, peaking at 4th and 7th days, then decreased after 14th day. Tumor necrosis factor-α( TNF-α) was also elevated in the lung tissue after C. Pneumoniae challenging. Both SB203580 and PDTC treatment effectively inhibited TNF-αand TLR2 mRNA expressions in lung. The inhibitory effect was more obvious by SB203580 treatment. Conclusion C. Pneumoniae can upregulate the expressions of TLR2 and TNF-α in lung, and TLR2/MAPK and TLR2 /NF-κB signal pathways may be involved in Chlamydia Pneumoniae pneumonitis.
ObjectiveTo summarize the clinical features and imaging features of CT in the omental torsion, and in order to reduce the misdiagnosis and missed diagnosis rate of imaging features.
MethodsThe data of 16 cases of omental torsion (secondary 15 cases, primary 1 case) and 286 cases of acute appendicitis (eliminated the subhepatic and retroperitoneal ectopic appendix) in our hospital from 1998 to 2014 were retrospectively analyzed.
ResultsEleven cases of omental torsion suffered from the shifting pain in right lower quadrant. No obvious shifting abdominal pain was observed in other 4 cases whose main manifestations were abdominal tenderness and rebound tenderness around umbilicus. The patient of the remaining 1 case had enclosed mass in the area of left groin with pain and suffered from continuous periumbilical pain. Abdominal spiral CT examination was performed in 16 patients before operation. Increased signal intensity of globular soft tissue, which deviating from McBurney's point, was found at level of distal umbilicus by preoperative spiral CT in 13 cases. One case of omental torsion associated with ncarcerated inguinal hernia was missed.
ConclusionsOmental torsion manifests chiefly shifting pain in right lower quadrant, abdominal tenderness, and rebound tenderness around umbilicus. It is easily confused with appendicitis. Abdominal spiral CT should be chosen as a preferred means in preoperative diagnosis of omental torsion.
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.
Objective To retrospectively assess the importance and imaging appearance of the signal intensity， the signal noise ratio (SNR), the contrast noise ratio (CNR) and enhancement patterns of early arterial phase in diagnosis and differential diagnosis of small hepatic nodular lesions on MRI. Methods Conventional spin-echo T2W, 2D GRE T1W plain scan and Gd-enhanced 3D-VIBE multi-phasic (early arterial, late arterial and portal venous phase) acquisitions were performed for 68 consecutive patients with 102 lesions on MRI. Native T2W and 2D GRE T1W were acquired first, then 3D-VIBE fast scanning at early arterial, late arterial and portal venous phase respectively. The SNR, CNR, signal intensity and enhanced pattern of the nodular lesions appearances on plain scan and eariy arterial phase were carefully observed. Results There were hyperintense in 102 (100%) lesions in T2W and hypointense in 95 (93.1%) lesions in T1W in plain scan. There were differences among the SNR, CNR of hepatic cyst, cavernous hemangioma, neoplasm metastasis and small hepatocellular carcinoma in T2W (P＜0.05)，the highest SNR and CNR of lesions were hepatic cyst. The SNR of small hepatocellular carcinoma and the CNR of hepatic cyst were highest in all the type diseases in T1W, there was significantly difference as compared with the other type diseases (P＜0.05). The enhancement rate of small hepatic nodular lesions was 76.5% in early arterial phase. The enhancement rate of small hepatocellular carcinoma and hepatic metastasis were 100% and 87.9% respectively. The non-enhancement rate of hepatic cyst were 100%. The common enhancement patterns of early arterial phase were peripheral enhancement which were 36 lesions (35.3%). The even enhancement and uneven enhancement were 22 lesions (21.6%) and 20 lesions (19.6%) respectively. Conclusion Qualitative and quantitative evaluation of MR signal intensity combined with the enhancement patterns of early arterial phase will help for qualitation and differential diagnosis of small hepatic nodular lesions on MRI.
