Objective To observe the effect of astragaloside IV (A) and SB203580 antagonize cadmium (Cd) toxicity on expression of associated protein and blood-testis barrier(BTB) in rats and to study the protective mechanism of A on it.Methods Totally 21 SD male rats were randomly divided into 7 groups, 3 rats per group:Cd [ intraperitoneally injected with 0.1%CdCl2,1mg/(kg?d)],Cd+A [at the above dose of CdCl2,at the same time with A,10mg/(kg?d)], and Cd +SB203580 [at the above dose of CdCl2,at the same time with SB203580,100μg/(kg?d)], each of the above groups was further divided into continuous five and ten days treatment groups .The control group was intraperitoneally injected with equal dosage of normal saline .The testes were studied by light , electron microscopy , immunohistochemistry and Western blotting .Results In the control group ,irregular and lightly stained nuclei of Sertoli cell ( Sc) in seminiferous tubules were observed by HE staining .A continuous electron density line of tight junction ( TJ) and normal ultrastructure of BTB were observed .After Cd treatment ,the vesicular formation in the Sc was observed .The ultrastructural damage of Sc and TJ was observed .Compared with the corresponding time point of Cd group ,these were weakened in morphology of testis and ultrastructure of TJ after Cd +A or Cd +SB203580 treatment .The positive products of zonula occludens-1 ( ZO-1 ) and claudin-11 were localized mainly in the base of the seminiferous tubule .After Cd treatment , the average absorbance (AA) of ZO-1 and Claudin-11 was decreased significantly compared with that of the control group (P<0.05).After Cd +A or Cd +SB203580 treatment,AA of ZO-1 and Claudin-11 were increased significantly compared with that of the Cd group(P<0.05),though lower than that of the control group .The result of Western blotting showed that phosphorylation-p38MAPK in Cd group was increased significantly compared with that of the control group (P<0.05).After Cd +A or Cd+SB203580 treatment, it was decreased significantly compared with that of the Cd group (P<0.05).Conclusion Cd decreases ZO-1 and Claudin-11 expression and damages ultrastructure of TJ in BTB , asⅣhas protective effect on it , and is related to inhibiting activation of p 38 MAPK pathway .

Objective To investigate the toxic effect of cadmium (Cd) on the ultrastructure ,expression of related protein and the signal molecule phosphrylated P38 mitogen-actived protein kinase(P-P38MAPK) of primary cultured rat sertoli cell(Sc) ,and the protective effect of astragaloside (A ) on it .Methods The primary cultured rat Sc were divided into the control group ,Cd (50 mol/L)group and Cd(50 mol/L) plus A(10 mg/L) group ,they were used for the electron microscope observation and the im-munohistochemistry detection of vimentin ,E-cadherin ,-catenin and P-P38MAPK .Results The Sc ultrastructural changes included that the swelled mitochondria ,abundant lipid droplets and dilated endoplasmic reticulum were found in the Cd group .Further ,apop-tosis occurred in some Sc .However these ultrastructure changes above mentioned were slighter in the Cd plus A group ;the immu-nohistochemistry showed that the positive products of vimentin ,E-cadherin and-catenin were obviously decreased in the Cd group (P<0 .05) ,and those in the Cd plus A group were higher compared with the Cd group(P<0 .05);the expression of P-P38MAPK in cytoplasm was increased in the Cd group ,and showed the trend to move from cytoplasm to nucleus ,meanwhile ,the positive prod-ucts expression in the Cd plus A group was lower than that in the Cd group (P<0 .05) .Conclusion Cadmium can cause the injury of the Sc ultrastructure ,damage of cytoskeletal protein and fibronectin ,and increase of P-P38MAPK level ;astragaloside can antago-nize the toxicity of cadmium on Sc ,the protective effect maybe related with the decrease of P-P38MAPK in Sc .

Bacteria isolated from rotten hides,one identified as Pseudomonas aeraginosa later, were shown to decompose fresh hides completely in 48 hours at room temperature. Strongly collagenolytic activity was detected when native collagen from calfskin was used as substrate. The optimal reaction pH value and temperature of the collagenace produced by P.aeraginosa are 7.5 and 32℃ respectively. EDTA and EGTA inhabit the collagenolytic activity severely while PMSF has little effect on it. Not only media components but also fermentation conditions have differents effect on the production of this collagenolyic enzyme.

Immunohistochemical and electron microscopic techniques and image analysis were employed to investigate the regulation of cardiac AT1A and AT2 subtype receptors in rats during cardiac remodeling following myocardial infarction (MI). Positive immunostaining for AT1A and AT2 receptors was observed in myocytes and vessels with AT1A being more than AT2. Three days after MI, disappearance of myocardial cross striation and fibroblast hyperplasia were found with electron microscopy. AT1A receptor protein expression in myocardial noninfarcted portion notably increased compared with that in sham-operated control rats (P<0.001). No apparent changes were observed in AT2 receptor (P>0.05). Two weeks after MI, myocyte cross striation and collagen deposition were found. Meanwhile, AT1A receptor staining decreased compared with that of three days after MI (P<0.01), but there was still more than that of the control (P<0.05). AT2 receptor was significantly increased compared with that of the sham-operated control rats (P<0.001). These results suggust that both AT1A and AT2 receptor protein expression was upregulated in noninfarcted myocardium after MI, and the regulation of AT1A and AT2 receptors after MI may be involved in post-infarction cardiac remodeling.

BACKGROUND:The production and release of a large amount of inflammatory factors caused by immune system inflammatory response mainly contributes to secondary spinal cord injury. OBJECTIVE:To investigate the effects of umbilical cord Wharton’s jely mesenchymal stem cel transplantation on repair of injured neurological function and expression of inflammatory factors monocyte chemoattractant protein 1 and interleukin 10 in rats with acute spinal cord injury. METHODS: Eighty-one healthy adult male Sprague-Dawley rats were randomly and equaly divided into sham operation, model and cel transplantation groups, with 27 rats per group. Rats in the latter two groups were subjected to hemisection of the spinal cord to establish acute spinal cord injury models. Rat models in the cel transplantation group received umbilical cord Wharton’s jely mesenchymal stem cel injection (1×106)via the tail vein. Rat neurological function was evaluated using the BBB score at different time points after spinal cord injury. The expression of monocyte chemoattractant protein 1 and interleukin 10 in injured spinal cord tissue was detected using ELISA assay at different time points after spinal cord injury. Migration and neuronal differentiation of umbilical cord Wharton’s jely mesenchymal stem cels in the injured spinal cord tissue were determined using immunohistochemical staining method. RESULTS AND CONCLUSION:Compared with the sham operation and model groups, rat neurological function was significantly recovered in the cel transplantation group (P < 0.05). Compared to the model group, monocyte chemoattractant protein 1 level in the serum and monocyte chemoattractant protein 1 mRNA and protein expression in the injured spinal cord tissue were significantly lower (P < 0.05), but interleukin 10 mRNA and protein expression in the injured spinal cord tissue was significantly higher (P < 0.05), in the cel transplantation group. In the cel transplantation group, umbilical cord Wharton’s jely mesenchymal stem cels could migrate to the injured region and express glial fibrilary acidic protein. These findings suggest that umbilical cord Wharton’s jely mesenchymal stem cels promote rat neurological function recovery by regulating the inflammatory response in the injured spinal cord tissue, which is likely to be one of mechanisms by which transplantation of umbilical cord Wharton’s jely mesenchymal stem cels treats spinal cord injury.

Based on site-specific transposition of an expression cassette into a baculovirus shuttle vector (Bacmid) which propagated in Escherichia coli, the Bac-to-Bac System provides a rapid and efficient method to generate recombinant baculoviruses and is widely used for high level expression of heterologous proteins. And the efficiency of recombinant baculovirus infecting cells plays an important role on the protein expression. In this study, we introduced an EGFP expression cassette driven by polyhedrin promoter into the p74 locus of Bacmid by homologous recombination. The target Bacmid-egfp was then transformed into E. coli DH10B containing the transposition helper plasmid to gain a new transposition receipt strain E. coli DH10Bac-egfp. Because of the intact attTn7 sites and lacZ', target gene cloned in a pFastBac vector can be transposed into the Bacmid-egfp shutter vector to construct recombinant baculovirus, which would allow the tracing of the target protein expression and the recombinant Bacmid transfection or recombinant baculoviral infection under fluorescence microscopes. Recombinant virus Bac-egfp-DsRed was constructed by transposing DsRed into the Bacmid-egfp in E. coliDHl0Bac-egfp, and the Sf9 cells infected with the recombinant virus expressed DsRed and EGFP efficiently. Another protein IL-6 fused with 6 x his tag was expressed and purified sucessfully from Sf9 cells infected with recombinant virus Bac-egfp-6 x his-IL6 constructed by the improved Bac-to-Bac system.
Animals ; Baculoviridae ; genetics ; Green Fluorescent Proteins ; genetics ; Interleukin-6 ; biosynthesis ; genetics ; Plasmids ; Polymerase Chain Reaction ; Recombinant Proteins ; biosynthesis ; Spodoptera

OBJECTIVETo investigate the effect of the basic fibroblast growth factor (b-FGF) to regenerate an autologous tissue-engineered cartilage in vitro.

METHODSThe Cells were harvested from the elastic auricular cartilage of swine,and were plated at the concentration of 1 x 10(4) cells/cm2 , studied in vitro at two different media enviroments: Group I contained Ham's F-12 with supplements and b-FGF, Group II contained Ham's F-12 only with supplements. The passage 2 cells (after 12.75 +/- 1.26 days) were harvested and mixed with 30% pluronic F-127/Ham's F-12 at the concentration of 50 x 10(6) cells/ml. It was injected subcutaneously at 0.5 ml per implant. The implants were harvested 8 weeks after the vivo culture and examined with the histological stains.

RESULTSThe chondrocytes displayed morphologically similar to the fibroblasts in the media containing basic-FGF. The number of cell doublings (after 12.75 +/- 1.26 days) in vitro culture was as the following: Group I, 70; Group II, 5.4. Eight 8 weeks after the vivo autologous implantation, the average weight (g) and volume (cm3) in each group was as the following: Group I, 0.371 g/0.370 cm3 Group II, 0.179 g/0.173 cm3 (P < 0.01). With the b-FGF in vitro culture, the cells were expanded by 70 times after 2 weeks. Histologically, all of the engineered cartilage in the two groups were similar to the native elastic cartilage.

CONCLUSIONThese results indicate that the basic-FGF could be used positively to enhance the quality and quantity of the seeding cells for the generation of the well-engineered cartilage.

Animals ; Cartilage ; cytology ; drug effects ; physiology ; Cell Division ; drug effects ; Cells, Cultured ; Chondrocytes ; cytology ; drug effects ; Female ; Fibroblast Growth Factors ; pharmacology ; physiology ; Male ; Regeneration ; drug effects ; Swine ; Tissue Engineering ; methods ; Transplantation, Autologous

OBJECTIVETo express P1B, P2A, P3AB and P3D cDNA gene fragments in prokaryotic system using thioredoxin fusion expression system; to investigate the antigenicity and application of recombinant protein.

METHODSBy using PCR technique, P1B, P2A, P3AB and P3D gene fragments were cloned. Choosing M47 as the expressive vector, the recombinant plasmid P1B, P2A, P3AB and P3D was constructed and expressed in Escherichia coli after inducing by IPTG. By anion exchange and affinity chromatography, purified recombinant protein was obtained. By using Western Blot analysis and indirect ELISA to detect its antigenic activity.

RESULTSFour recombinant plasmids was proved to be constructed successfully by sequencing and the correct molecular weight of their expression products. Recombinant proteins were obtained in BL21 (DE3) and purified after Ni2+ affinity chromatography. Western Blot analysis and indirect ELISA showed that P2a had specific antigenicity.

CONCLUSIONThe P2a protein expressed in prokaryotic system was proved to have specific antigenicity. The indirect ELISA distinguished 24 positive sera from 24 negative sera. It is very likely that P2a can be an antigen to diagnose acute patients of hepatitis A and differentiate inactivated vaccine-induced immunity from an infection.

Blotting, Western ; Cloning, Molecular ; Enzyme-Linked Immunosorbent Assay ; Escherichia coli ; genetics ; Gene Expression ; Hepatitis A virus ; genetics ; immunology ; metabolism ; Humans ; Polymerase Chain Reaction ; Recombinant Proteins ; immunology ; metabolism ; Viral Proteins ; genetics ; immunology ; metabolism

OBJECTIVETo study the expressions of matrix metalloproteinase 2 (MMP2) and E-cadherin (E-CD) in salivary mucoepidermoid carcinoma, and their relationship with clinical stages, pathological grading, lymph node metastasis and prognosis.

METHODSSurgical specimens of salivary mucoepidermiod carcinoma and normal salivary gland tissue were collected. MMP-2 and E-CD were stained immunohistochemically with streptavidin peroxidase method.

RESULTSThe expression of MMP-2 was increased and the expression of E-CD was reduced or negative in salivary mucoepidemoid carcinoma compared with those of the normal salivary gland. Expression of MMP-2 and E-CD was closely correlated with lymph node metastasis of the mucoepidermoid carcinoma. MMP-2 was positively correlated with the prognosis of mucoepidermoid carcinoma, and E-CD was negatively correlated to the prognosis of mucoepidermoid carcinoma.

CONCLUSIONThe expression of MMP-2 and E-CD is closely correlated with the metastasis and prognosis of salivary mucoepidermoid carcinoma.

Cadherins ; biosynthesis ; genetics ; Carcinoma, Mucoepidermoid ; metabolism ; pathology ; Humans ; Matrix Metalloproteinase 2 ; biosynthesis ; genetics ; Neoplasm Invasiveness ; Neoplasm Metastasis ; Prognosis ; Salivary Gland Neoplasms ; metabolism ; pathology

OBJECTIVETo investigate the association between the C311S polymorphism of paraoxonase 2 (PON2) gene and ischemic stroke in Chinese type 2 diabetes mellitus (T2DM) patients.

METHODSA case-control study of 279 Chinese subjects (including 162 T2DM with or without ischemic stroke and 117 non-diabetic control) was performed. Genotype frequencies of C311S polymorphism were studied by polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP) analysis with DdeI digestion.

RESULTSC311S polymorphism of PON2 gene was detected in Chinese with the C/S allele frequencies 0.145 and 0.855. The frequency distribution showed significant difference between Chinese and Asian Indian. Furthermore, the genotype distribution (SS, CS and CC) of the PON2 C311S gene polymorphism exhibited a significant difference between T2DM patients complicated with ischemic stroke and T2DM without ischemic stroke, the former had a significantly higher C allele frequency(P<0.05).

CONCLUSIONThe above data indicate that the polymorphism at codon 311(Cys --> Ser)in the PON2 gene is associated with ischemic morbidity in Chinese T2DM patients and C allele might be a risk factor.

Adult ; Aryldialkylphosphatase ; genetics ; Asian Continental Ancestry Group ; genetics ; Diabetes Mellitus, Type 2 ; complications ; genetics ; Female ; Humans ; Male ; Middle Aged ; Polymorphism, Genetic ; Stroke ; etiology ; genetics