In recent years, the importance of tyrosine phosphorylation in the nervous system of mammalian is gaining recognition. Tyros ine protein kinases exert important modulatory effect on the proliferation, diff erentiation, migration and metabolism-related singal transduction pathways in c ells. In this paper we reviewed the signal cascade process of three different ty rosine protein kinase families, including Trk, Src and Eph tyrosine protein kina se families. Furthermore, we discussed important role and possible mechanisms of these tyrosine protein kinases on the neuron synapse plasticity and learning an d memory process.

Objective To explore the value of peak systolic displacement of mitral annulus in evaluating left ventricular systolic function by speckle tracking imaging(STI).Methods The study population consisted of 96 subjects. The apical four-chamber view and two-chamber view were obtained and the systolic displacements of mitral annulus were measured at lateral, spetum, anterior and inferior mitral annulus (MADlat, MADsep, MADant, MADinf).The systolic displacements of mitral annulus midpoint (MADmid) and its ratio to the length of left ventricle at end-diastole(MADmid%) were calculated.Left ventricular ejection fraction(LVEF) was measured by three-dimensional echocardiography.The correlation of these displacements parameter with LVEF was analyzed.Results ① There was no significant difference among MADsep, MADlat, MADant, MADinf and MADmid(P>0.05).②There was significant correlation between LVEF and these parameters (P <0.01) ,and MADmid and MADmid% showed an excellent correlation with LVEF (r = 0.87 and 0.89 respectively, P<0.01).③The cut-off value of MADmid for LVEF>50% was 8.9 mm with a sensitivity of 95% and a specificity of 80% while the cut off value of MADmid% for LVEF>50% was 10.9% with a sensitivity of 95% and a specificity of 85%.Conclusions Displacement of mitral annulus by STI showed an excellent correlation with LVEF, and it may be a new promising method for routine evaluation of left ventricular systolic function with its high feasibility, simplicity and accuracy.

Objective To investigate the influence of early enteral nutrition therapy on the intestinal barrier function and immune response of the patients with radiation enteritis (ER) so as to find a relatively simple and effective method to treat RE.Methods Fifty-six patients with radiation enteritis (RE) diagnosed by colonoscopy,X-rays,and pathology were randomly divided into 2 equal groups:experimental group undergoing enteral inutrition therapy,and control group undergoing conventional therapy only.Peripheral blood samples were collected 1,11,and 21 days after admission.Plasma diamine oxidase (DAO),D-lactic acid,endotoxin,and lactulose/mannitol (L/M) ratio,and levels of IgG,IgM,and IgA,and CD4/CD8 ratio were examined.Five cases from the experimental group and 5 cases from the control group underwent second-time operation because of incomplete intestinal obstruction,intestinal stenosis,or recurrent tumor respectively.The biopsy specimens of the terminal ileum or distal descending colon taken during the first and second operations underwent pathological examination.Peripheral blood samples were collected 1,11,and 21 days after admission.Plasma diamine oxidase (DAO),D-lactic acid,endotoxin,and lactulose/mannitol (L/M) ratio,and levels of IgG,IgM,and IgA,and CD4/CD8 ratio were examined.Results There were no significant differences in the intestinal function and blood immunological indices between these 2 groups.The levels of DAO,D-lactic acid,and endotoxin,and the L/M ratio 11 days after admission of the experiment group were all significantly lower than those of the control group (t =2.568,2.427,2.143,2.443,P ＜ 0.05),and all those indices 21 days after admission of the experiment group were all much more significantly lower in comparison with the control group (t =6.019,12.834,7.837,7.997,P ＜ 0.01).The levels of IgG,IgM,and IgA,and CD4/CD8 ratio 11 days after admission of the experimental group were all significantly higher than those of the control group (t =2.096,2.211,2.182,P＜ 0.05,and t=2.301,P＜ 0.05),and the differences became much more significant 21 days after admission (t =2.703,2.679,3.138,P ＜ 0.01,and t =5.107,P ＜ 0.01).The height of the intestinal villa and the thickness of the mucosa of the specimens taken at the second-time operation were both much greater than those at the first-time operation.Conclusion Early enteral support therapy helps effectively maintain the intestinal barrier and immune response function of the RE patients.

Objective To study the expressions of caudal type homeodomain transcription factors CDX1 and CDX2 in different subtype of intestinal metaplasia (IM) and gastric eareinoma,and investigate their roles in the development and progression of IM and gastric carcinogenesis, and determine the relationship between IM and gastric carcinoma. Methods Forty eases of chronic superficial gastritis, 40 cases of chronic atrophic gastritis (CAG), 46 eases of CAG with IM, 40 cases of gastric carcinoma, and 32 eases of IM foci in para-eancerous tissues were selected respectively to construct tissue microarrays. Immunohistechemistry and in situ hybridization were used to assess the expressions of CDX2 protein and CDX1, CDX2 mRNA in different gastric lesions respectively. Results The proportion of type Ⅲ IM in IM foci in para-caucerous tissues was significantly higher than that in CAG (56.25% vs 21.74% ,P< 0.01). There was no expression of CDX1, CDX2 mRNA and CDX2 protein in chronic superficial gastritis and CAG without IM. The expression of CDX2 protein and CDX2 mRNA in CAG with IM, para-cancerous tissues and gastric carcinoma was 69.57%, 53.12%,42.50% (CDX2 protein) and 63.04%,46.88%,35.00% (CDX2 mRNA), respectively. The exprossions of CDX1 mRNA in above throe gastric lesions were 67.39%, 50.00%, 40.00%, respectively. The expressions of CDX2 protein and CDX2, CDX1 mRNA in gastric carcinoma were significantly lower than those in CAG with IM (P< 0.01). But there was no significant difference between gastric carcinoma and IM foci in para-cancerous tissues (P> 0.05). Furthermoro,the expressions of CDX2 protein were significantly associated with histological type of gastric carcinoma, which in intestinal-type was significantly higher than those in diffuse-type(54.55% vs 27.78%, P< 0.05). The expression of CDX2 protein in type Ⅲ IM was also significantly lower than that in type Ⅰ IM(46.43% vs 79.31%,P< 0.05). Conclusions CDX1 and CDX2 may play important roles in the development and progression of IM and gastric carcinoma, and may be new gastric carcinoma associated genes. Type Ⅲ IM is a precancerous lesion of the intestinal-type gastric carcinoma.

0.05). Conclusion IBS may be related to the changes of the serum level of PYY,but not to the changes of PYY receptor.

Objective To express and purify mammalian glycosylation modified trimeric Ebola virus trimeric glycoprotein (EBOV-GP) using novel glycoengineered Pichia pastoris.Methods The EBOV-GP and EBOV-GPΔMLDΔTM genes were cloned into the pPICZ-αA vector,electrochemically converted to glycoengineered Pichia pastoris,and compared with EBOV-GP expressed in HEK-293T cells.Glycosylation was analyzed by PNGaseF and EndoH digestion,while the target protein was purified by affinity chromatography and ion exchange chromatography.N-terminal sequencing was used to determine whether the signal peptide was correctly cleaved during protein translation and gel column analysis was used to find out whether the trimeric structure was formed.Results The results of PNGaseF showed that EBOV-GP expressed by glycoengineered Pichia pastoris and HEK-293T cells had the same relative molecular mass and N-glycosylation degree.EndoH digestion showed that the N-glycosylation modification of EBOV-GPΔMLDΔTM was in a non-high mannose form.N-terminal sequencing showed that the signal peptide of the GP protein itself was correctly excised.Gel column analysis showed that the purified protein was in a trimeric form.Conclusion An EBOV-GP is obtained with complex glycosylation modification based on Glycoengineered Pichia pastoris.

Objective To observe the changes of peptide YY (PYY) and its receptors in rats with ulcerative colitis (UC) by detecting both the serum level of PYY and jejunum epithelial cells in UC rats. Methods Rats were randomly divided into UC group, diarrhea-irritable bowel syndrome (D-IBS) group and control group. We measured the serum level of PYY by radioimmunoassay and made radioligand analysis of two basic parameters reflecting the characteristics of PYY receptors: dissociation constant (Kd) and maximum binding capacity (Bmax). Results The serum level of PYY was higher in UC and D-IBS groups than in normal group (P<0.001), and it was higher in UC group than in D-IBS group (P<0.001). However, the values of Kd and Bmax in UC group did not differ significantly from those in D-IBS and normal groups (P>0.05). Conclusion The serum level of PYY in UC group was significantly higher than that in normal group and D-IBS group; therefore, we assume that the change of serum PYY level may be related to not only the symptom of diarrhea but also inflammation. Kd and Bmax in neither UC group nor D-IBS group were significantly different from those in normal group, which indicates that the symptom and inflammation in UC may have nothing to do with the changes of PYY receptors.

Objective To analyze the expression of C-reactive protein(CRP)in 2-12-year-old children with acute otitis media(AOM),we can use CRP as a strong evidence for the usage of antibiotics in the diagnosis and treatment of otitis media.Methods 250 children with AOM were selected as the research subjects.52 cases refused to test,CRP was detected in 198 children(231 ears).CRP was examined in all patients before treatment,they were followed up for 1 month.After treatment,CRP was reviewed in three days,one week and one month,respectively.Results In 198 children(231 ears),71 ears were recovered,33 ears improved,and 127 ears were ineffective in three days,the effective rate was 45.0%(104/231).100 ears were recovered,45 ears improved,and 86 ears were ineffective in one week,the effective rate was 62.8%(145/231).121 ears were recovered,56 ears improved,and 54 ears were ineffective in one month,the effective rate was 76.6%(177/231).The effective rate were significantly different among the three groops(x2=14.643、48.406,10.494,all P<0.05).Among 198 children,188 ears were in the low expression group,43 ears were in the high expression group.After three days of treatment,the composition ratio of group B and group C was changed(x2 =5.979,P=0.014),while group A had a significant change(x2 =13.948,P=0.000).Therefore,early use of antibiotics was effective in reducing CRP,so as to reduce the clinical symptoms in children.Conclusion CRP can be used to guide antibiotic monitoring.

Objective To develop an interleukin-4(IL-4) antagonist named M5-IgG1Fc protein constructed by genetic engineering of antibody Fc fragment-cytokine mutein fusion protein which has a long half-life time in plasma.M5-IgG1 Fc protein binds to IL-4 receptor but cannot activate downstream signalling pathway , which provides a basis for drug develop-ment for allergic diseases .Methods The synthesized interleukin-4 mutant gene ( named M5 ) was cloned into the expres-sion vector pBV220 and transformed into E.coli DH5α.Chimeric gene M5-IgG1Fc obtained by overlap extension (SOE) method was transformed into glycoengineered Pichia pastoris GJK01 through expression vector pPICZαA .Then M5-IgGFc fusion protein was obtained by protein purification after being induced by methanol in 72 hours.The anti-IL-4 biologicial ac-tivity assay of M5 and M5-IgG1 Fc was performed with CTLL-2/IL-4R cells and detected with MTT colormetry .Finally,the half-life time of M5 and M5-IgG1 Fc protein in mice was compared by detecting the remaining amount in plasma with ELISA kit.Results The M5 protein expressed in E.coli and M5-IgG1 Fc fusion protein expressed in P.pastoris GJK01 both had IL-4 antagonistic bioactivity .The EC50 of both, which inhibited 5.6 ×10 -2 nmol/ml of IL-4, were 0.31 ±0.05 and 0.77 ± 0.03 nmol/ml,respectively.The maximum of M5 in plasma at 0.5 h was 5.8 ×10 -2 nmol/ml but the remaining amount was 2.8%of the maximum at 2 h.M5 protein could not be detected after administration at 8 h because of the detection line . The maximum of M5-IgG1 Fc fusion protein was 4.7 ×10 -2 nmol/ml,while fusion protein M5-IgG1 Fc decreased to 4.3%of its maximum at 120 h and could not be detected at 168 h.Conclusion M5 protein has IL-4 antagonistic bioactivity .M5-IgG1 Fc fusion protein expressed in glycoengineered P.pastoris GJK01 has IL-4 antagonistic bioactivity and long retention time in mice,which can be potentially used for treatment of allergic diseases .

Hepatitis B virus ( HBV) is an important pathogen threatening to human health. Up to date, various of cell infection models and animal models for HBV and the host are widely used in the exploring research of infection mechanism, new drug development and effective therapeutic method for HBV. However, these models have some defects, such as low infection rate, rather short infective stage, and comparatively large species differences with human, and so on. Among them, the biggest problem is that these models cannot completely simulate HBV infection process and pathological changes naturally occurred in human. Herein, the major HBV infection models developed in the past fifteen years, as well as the latest research progress, are presented as a brief review, to provide a reference for constructing novel HBV infection models in the future.