The mice were administered with 10~40mg?kg~(-1)?d~(-1) SHP [Sargassum hemiphyllum(Turner) C.Agardh polysaccharides,SHP] ip for 7d before 5Gy ?-rays irradiation to observe the effect of SHP on the mRNA expression of CD~+_(34) and SCF(stem cell factor),and to study the mechanism of SHP against irradiation on the hematopoietic system in irradiated mice.Flow cytometry was used to detect number of bone marrow cells and the mRNA expression of CD~+_(34) and SCF were analysed by RT-PCR test.The results showed that the percentage of CD~+_(34) cells was decreased by ?-rays irradiation(5Gy) and SHP(10～40mg?kg~(-1)) could increase significantly the percentage of CD~+_(34) cells to exhibit a protective effect of SHP on bone marrow in irradiated mice.Expressions of CD~+_(34) and SCF mRNA were lower in model group than those in conrol group and the expressions were higher in three test groups than those in model group.The results indicated that the increases of expressions of CD~+_(34) and SCF mRNA could be a mechanism of SHP against irradiation on the hematopoietic system in mice.

Objective To explore the efficacy and postoperative survival times of stereotactic radiosurgery by X-knife in the treatment of brain metastatic tumors.Methods Between March 1996 and March 2008,520 patients with brain metastatic tumors were treated in our hospital by stereotactic radiosurgery using X-knife.Among the cases,336 had single metastatic lesions,and 184 presented with multifocal tumors(2 lesions in 51 patients,3-5 lesions in 63,and 6-10 lesions in 70).The tumors sized 5 to 35 mm in diameter with a mean of 16.4 mm.Stereotactic radiosurgery was carried out in the cases with a mean central dose of 22 Gy(20 to 25 Gy),and mean marginal dose of 12 Gy(10 to 14 Gy).Over 80% of the lesions were encircled with the dosage.Results The 520 patients were followed up for 8 to 36 months(mean,20 months).CT and MRI performed in the 6th months postoperation showed complete response in 218 patients(41.9%),partial response in 182(35.0%),no response in 78(15.0%),and progressed disease in 42(8.1%).The overall control rate of the tumors were 91.9%(478/520).In this series,the 6-months survival rate was 85.0%(442/520),12-month survival rate was 68.1%(354/520),and the 1-year and 3-year survival rates were 40% and 5.5% respectively.The medium survival time was 12.6 months.Conclusions Stereotactic radiosurgery is an effective method for brain metastatic tumors.It can improve the life quality and survival time of the patients.

AIM: To observe the expression of proteins induced by whole-body irradiation in mice with low dose X-rays and their biological activity. METHODS: To analyse the expression of protein induced by whole-body irradiation with 75mGy X-rays and sham-irradiation, the method of gel filtration with Sephadex G-100 and HPLC were used. The biological activity of protein expressed in thymocytes was observed by mouse splenocyte proliferation and chromosome aberration of human peripheral blood lymphocytes. RESULTS: HPLC analysis showed that there was a marked decrease in expression of 24.5 kD protein molecule in the fractions of thymocyte extract in comparison with the corresponding fractions from the sham-irradiated control mice. These protein fractions from the thymocytes of the irradiated mice at the concentration of 6.25 mg/L showed both inhibitory effect on normal T cell proliferation and protective effect on the chromosome damage induced by high dose radiation. CONCLUSION: Down regulation of 24.5 kD protein molecule expression may have implications in the mechanism of immunoenhancement and cytogenetic adaptive response induced by low dose radiation.

The current teaching material system of laboratory medical science is based on the idea of"superimposed single-subject"and causes severe conflict of teaching time restriction and a large quantity of teaching content.In order to enable students to access to more important knowledge and cultivate their creative thinking ability,it is essential to conduct reform on single-subject curriculum model and reconstruct the course system of the laboratory medical.In addition,it is of great importance to re-evaluate,optimize and reorganize the new laboratory medicine courses and make rational use of educational resources.

Aim To investigate the effect of metformin (Met) on connexin43(Cx43) expression in H9c2 cells cultured with high glucose and the relevant mecha-nisms.Methods Rat myocardial cells H9c2 were cul-tured with high glucose , then combined with 3μmol· L-1 and 5 μmol · L-1 of Met for 24 h respectively . The viability and toxicity of H9c2 cells were detected by MTT and LDH , respectively .The expression and distribution of Cx43 were detected by immunofluores-cence staining .The intracellular oxygen species reac-tive ( ROS) level was detected by fluorescencemicrosco-py.And the expression of Cx43, P-AMPK, AMPK and GAPDH was determined by Western blot .Results The viability of H9c2 cells was increased and the level of intracellular ROS was decreased in Met group , while there existed no significant difference in LDH release among groups.Met significantly increased the phos-phorylation of AMPK and the expression of Cx 43, and improved the distribution of Cx 43 also.Conclusion The beneficial effect of Met on cardiovascular system in diabetic patients may via up-regulating the expression of Cx43 and down-regulating of intracellular ROS through activation of AMPK .

Aim To investigate the effect of simvastatin ( Sim ) on endogenous antioxidant system after acute myocardial infarction ( AMI ) and its potential mecha-nisms. Methods The acute myocardial infarction ( AMI ) rat models were made by ligation left anterior descending of coronary artery. Then the successful models were randomly divided into myocardial infarc-tion group ( MI group) and simvastatin group ( Sim,20 mg·kg-1·d-1), another group without ligation left anterior descending of coronary artery served as sham group(Sham group). The Sim group was administered simvastatin by gavage for 7 days. MI group and Sham group received saline. Hemodynamic parameters, lipid levels, troponinI ( c-TnI ) and lactate dehydrogenase ( LDH) concentrations were examined after 7days, and the levels of superoxide dismutase ( SOD) and glutathi-one peroxidase ( GP) of myocardial antioxidant system were detected by ELISA. The expression of cardiac p-Akt and p-eNOS protein were detected by Western blot. Results Acute myocardial infarction significant-ly lowered cardiac hemodynamic parameters, increased serum c-TnI and LDH levels, lowered levels of SOD and GP, and lowered the expression of p-Akt and p-eNOS protein. However, Sim could effectively prevent the deterioration of cardiac function, reduce serum c-TnI and LDH levels, increase levels of SOD and GP, and increase p-Akt and p-eNOS protein expression. Conclusion Early using Sim can effectively improve heart function after acute myocardial infarction, acti-vate myocardial antioxidant system,and reduce myocar-dial necrosis, which may be related to increasing the expression of p-Akt and p-eNOS.

Linoleic acid (C18∶2n-6) and ?-linolenic acid (C18∶3n-3) are found widely in fungi, plants and some lower animals. However, they can not be synthesized in mammals due to lack of △12 and ?-3 fatty acid desaturases. To enable endogenous production of essential fatty acids in mammalian cells, here the stable expression of a Caenorhabditis elegans gene FAT-2 encoding △12 fatty acid desaturase in CHO cells was reported. First, the FAT-2 coding sequence was cloned by RT-PCR. To facilitate high level synthesis of heterogeneous protein, the codon usage of the fatty acid desaturase genes was optimized according to the codon preference of mouse by site-directed mutagenesis, 2 synonymous mutations were introduced into FAT-2 gene by overlapping PCR. The codon-modified gene was finally fused to pBudCE4.1 vector (Invitrogen) under the control of CMV promoter. The expression vector pBudCE-FAT2 was linearized with NheⅠ, and then transfected CHO cells, the cells were under Zeocin selection for nine days and then propagated, then the transfected cells were harvested. The genome and total RNA were isolated for PCR and Norhern blot ananlysis. The results revealed that FAT-2 gene has been integrated into the genome of CHO cells and expressed properly. Fatty acids of total cellular lipids were analyzed by gas chromatography. The results indicate that the expression and function of △-12 fatty acid desaturase resulted in accumulation of linoleic acid. The levels of linoleic acid in transgenic cells were 2.4-fold higher than those in wild-type cells. The moderate linoleic acid in CHO cells was derived from cell culture media uptaken by cell membrane. The results demonstrate that a heterogenous desaturase gene can function well in mammalian cells and prove that transgenic approach is an efficient strategy for changing fatty acid composition of mammals.

Objective To explore if grape seed polyphenols (GSP) reverses human breast cancer multidrug resistance. MethodsIn this study,adriamycin-resistant human breast carcinoma cells ( MCF-7/ADR ) and its parental cells (MCF-7) were used to determine the effect of GSP. MTT assay was adopted to evaluate the cytotoxity. Western blot and Northern blot were performed to observe the expression of MDR1 in MCF-7/ADR. Adriamycin accumulation was measured by flow cytometry (FCM). ResultsGSP ( 1.2 mg/L ,2.4 mg/L) inhibited the expression of P-gp to 80.83%( t =5.58,P

Objective To investigate the biological function of NS5ABP37 and to look for proteins interacting with NS5ABP37 protein in hepatocytes. Methods We constructed bait plasmid expressing NS5ABP37 protein of hepatitis C virus (HCV) by cloning the gene of NS5ABP37 protein into pGBKT7, then the recombinant plasmid DNA was transformed into yeast AH109 (α type). The transformed yeast AH109 was mated with yeast Y187 (α type) containing liver cDNA library plasmid in 2×YPDA medium. Diploid yeast was plated on synthetic dropout nutrient medium (SD/-Trp-Leu-His-Ade) containing X-α-gal for selection and screening. After extracting and sequencing of plasmids from positive (blue) colonies, we made a sequence analysis by bioinformatics. Results We screened twenty-five proteins binding to NS5ABP37, including Homo sapiens cyclin Ⅰ (CCNI) gene, Homo sapiens matrix metallopeptidase 25 (MMP25) and Homo sapiens talin 1. Conclusion The yeast-two hybrid system is an effective method for identifying hepatocyte proteins interacting with NS5ABP37 of HCV. And the biological function of NS5ABP37 may be associated with glycometabolism, lipid metabolism and apoptosis.

Objective By using percutaneous endovascular microcatheter technique to establish an animal model of coronary microembolization in mini-swine which is suitable for long-term observation.Methods Coronary microembolization was established in 10 mini-swine by infusing 15 × 10~4 microspheres (φ45μm) selectively into the left anterior descending artery (n = 10). Coronary flow reserve (CFR) was measured by Doppler wire and left ventricular eject fraction (EF) was assessed by echocardiography.Hematoxylin and eosin (HE) staining and nitroblue tetrazolium (NBT) dye were used to demonstrate the presence of microembolization after the procedure of coronary microembolization. The ultra-structures of cardiomyocyte were observed by transmission electron microscopy (TEM). Before sacrifice, the CFR measurement and coronary angiography were performed again in survival animals. Results The coronary microvascular integrity (CFR < 2.0) and left ventricular function (EF < 50% ) were damaged by coronary microembolization. One month after the procedure, all the 10 animals survived and were able to receive the angiography and CFR measurement again. HE staining and NBT dye could demonstrate the presence of microembolization. The edema and fibrosis of cardiomyocytes could be revealed with TEM. Conclusion The animal model of coronary microembolization can be established in mini-swine by using percutaneous endovascular microcatheter technique. The model is suitable for long-term observation, the preparation is technically-simple and minimally-invasive with very low mortality. Therefore, this kind of animal model is an ideal experimental form for studying the mechanism of coronary microembolization.