The technique of extracting and refining mucopolysaccharide from Dasyatis akajei cartilage obtained was studied and the content of mucopolysaccharide was measured.The results showed that when the content of NaOH was 6%,temperature 40℃, extracting time 6h,followed neutral protein enzyme dissolution for 7h under 40℃,protein precipitation with trichloroacetic acid and 4 times volume 95% C_(2)H_(5)OH for polysaccharide precipitation.the extraction rate was over 21%, the product was white powder and its purity was about (84.53%).Physical and chemical properties of the mucopolysaccharide were identified.

On the basis of motor status of the frontalis musecle and the mouth corner 4 to 20 days after the onset, the degree and prognosis of facial paralysis of 218 cases were evaluated for 1～3 years. 44 cases belonged to neurapraxic type. In this type,visible motor recovery of frontalis and mouth corner was observed in 15 to 29 days after onset. Mild paralysis type (93 cases), in whom visible motor power of mouth corner appeared following the motor recovery of frontalis 14～20 days after onset, showed a total recovery in 24 to 40 days (84%). In moderate paralysis type, slight or absent visible motor recovery of frontalis was observed. Visible frontalis and mouth corner motor power appeared 20 days to 2 months after onset, with normal frontalis recovery in 42 cases.In 3 cases frontalis motor power recovered for 25% to 50%, and in 45 cases (67%) residual symptoms and complications were observed. Severe paralysis type consisted of 75% of patients, 36 patients, in whom the frontalis did not completely recover and 92% had residual symptoms and complications.Therefore, according to motor status of the frontalis and mouth corner, facial paralysis could be classified in predicting the prognosis.

ObjectiveIn our study, the electrical current intensities of 0.05ms square wavelenth in I/t curve were explored in diagnosing damage degree and predicting prognosis of facial paralysis.MethodsAccording to tested 0.05ms intensity values of fronto-occipital muscle and orbicular muscle of mouth in healthy side of 236 cases with facial paralysis and that values of 30 cases with completely-absent nerve, the standard of diagnosing slight, moderate and severe facial paralysis was made. A follow-up survey for the recovery of 198 cases evaluated by House-Brachmann facial nerve grading system was made for one to three years.ResultsIt is found that there were 113 slight cases and 89% of them recovered in 40 days, 112 cases reached to H-B Ⅰgrade; 82% of 49 moderate cases recovered in 4-5 months; 36 severe cases appeared visible mouth corner movement in 2-5 months after onset, and 92% of them had complications or sequelae.Conclusions Intensities of 0.05ms square wavelenth can help in diagnosing damage degree and predicting prognosis of facial paralysis.

Objective To investigate the effects of pulsed magnetic fields of different intensity on carotid restenosis (CRS), post carotid endarterectomy (CEA) and the expression of matrix metalloproteinase-2 (MMP-2)in vascular smooth muscle cells (VSMC). Methods An animal model of carotid altherosclerosis was established in 50 New Zealand rabbits by using air-drying lesions combined with high fat feed. After two months, the rabbits were treated with bilateral CEA, and then divided randomly into 3 groups. Two of the groups were treated with ei-ther 0.6 or 1.0 T pulsed magnetic fields, while the third group served as an untreated blank control. Changes in the pathology of the tunica intima were observed 1, 2 and 3 months after the CEA using morphologic analysis, and the expression of MMP-2 in the VSMC was determined using immunohistochemistry. Results The histological a-nalysis showed that the total luminal area, plaque area, the maximum plaque thickness and the proportion of siena-sis in the treated groups were all significandy lower, on average, than in the control group. At all three time points the average improvements in the 1.0 T group were significantly greater than in the 0.6 T group. The average ex-pression of MMP-2 in the treated groups was significantly lower than in the control group, especially in the 1.0 T group. Conclusions Pulsed magnetic field therapy positively influences CRS and the expression of MMP-2 in VSMC. Reduced MMP-2 expression might be one of the mechanisms through which pulsed magnetic fields prevent or lessen carotid restenosis post CEA.

This study aimed to explore the cognitive dysfunction of and hippocampal neuron damage to Wistar rats with STZ-induced diabetes at different morbidity time. All Wistar rats in the tests received intraperitoneal injections of streptozotocin (STZ; 60 mg/kg) to induce type 1 diabetes. The concentration of blood glucose and the body weight were investigated, the cognitive ability of rats was assessed using a standardized Y-maze, and the apoptotic neurons in the CA1 of the hippocampus were also examined by using the HE staining. While the sickening time was prolonged, the blood glucose concentration of the experimental rats increased continuously and the body weight decreased. On the 70th day after STZ administration, the neuronal loss in the hippocampal CA1 region increased and the working errors increased in rats with the diabetes. The results showed that Wistar rats could complicate with diabetic encephalopathy in 70 days after injection of STZ for inducing the diabetes.
Animals ; Blood Glucose ; Body Weight ; CA1 Region, Hippocampal ; cytology ; pathology ; Cognition ; Cognition Disorders ; physiopathology ; Diabetes Mellitus, Experimental ; physiopathology ; Diabetes Mellitus, Type 1 ; Neurons ; pathology ; Rats ; Rats, Wistar ; Streptozocin

BACKGROUND:With the development of science and technology and modern aerospace, the effects of mechanobiology in extreme mechanical environment—high acceleration are becoming an issue of concern. Studies have shown that high acceleration has certain effects on the cels. OBJECTIVE:Based on a centrifuge, to design a cel loading centrifuge used for exploration of cel mechanobiology under high acceleration. METHODS:For the cel loading centrifuge, a culture plate or/and culture bottle ful of culture fluid was/were loaded with constant acceleration or variable velocity to explore the experimental feasibility. Besides, a finite element model was built by ANSYS software according to structure and properties of the rotor. The rotor system was calculated under equilibrium and dangerous working conditions, respectively, to analyze the stress and deformation distribution. Moreover, the strength of the main shaft was checked under the dangerous working conditions. Then the analysis results of ANSYS were compared with the results of strength check. RESULTS AND CONCLUSION:Experimental findings showed that the culture plate or/and the culture bottle could be used for (0-40)×g highly constant acceleration or variable acceleration loading. Through the simulation and comparison analysis, we confirmed the reliability of the cel loading centrifuge. This cel loading centrifuge can be used to implement the study of cel mechanobiology under high acceleration in the general biology laboratory. It also provides a basis for wide application of cel loading centrifuge in the future.

Objective To investigate the effects of trichostatin A (TSA) on cell proliferation and cell cycle in human gastric cancer cell line SGC-7901 in vitro and its mechanism. Methods SGC-7901 cells were treated with 0.1, 0.5 and 2.0 μmol/L of TSA for 24 hrs. Growth inhibition rates of cells were measured by MTT assay and cell cycles were detected by flow cytometery (FCM). Expressions of cyclin D1 and p21 mRNA were measured by real-time PCR. Results The proliferations of SGC-7901 cells were inhibited when treated with TSA for 24 hrs. The inhibition rates in groups treat with 0.1, 0.5 or 2.0 μmol/L of TSA were 3.52%±6.11%, 13.29%±4.13% or 14.24%±2.80% ,respectively. The cell percentage of G0/G1 phase were higher in 0. 5 pznol/L group (71.26%±0.51%) and 2.0 μmol/L group (71.03%±0.12%) compared with control group (51.12%±1.17%). The cell percentage of S phase were lower in 0.5 μmol/L group (13.55%±0.44%) and 2.0 μmol/L group (10.63%±0.63%) compared with control group (34.60%±0.60%). The expression of cyclin D1 mRNA was down-regulated, whereas p21 mRNA expression was up-regulated. Conclusions TSA inhibits SCG-7901 gastric cancer cell proliferation by affecting the cell cycle control gene eyclin D1 and p21 mRNA expressions, which induce G0/G1 cell phase cycle arrest and ultimately impact on the growth of tumor cells.

ObjectiveTo assess the effects of DNA methyhransferase 1 ( DNMT1 ) gene silencing on DNMTs activity and methylated CpG sites of hMLH-1 in pancreatic cancer cell line PaTu8988.Methods DNMT1 siRNA and negative control siRNA was constructed by Ambion Company of United States.Then they were transfected into pancreatic cancer cell line PaTu8988 at the concentrations of 15,30 nmol/L,and the cells without transfection was used as the control group.Real-time PCR and Western blotting were applied to detect the DNMT1 mRNA and protein expression,and DNMTs activity was detected by using DNMTs activity assay kit.Change of methylation of CpG island of hMLH-1 was detected by bisulfite sequencing PCR (BSP).The expression of hMLH-1 mRNA was detected by Real-time PCR.ResultsAt 48 h after transfection,Realtime RT-PCR analysis showed that the levels of DNMT1 mRNA in DNMT1 siRNA group ( 15 nmol/L) and DNMT 1 siRNA group (30 nmol/L) were 0.573 ± 0.026 and 0.143 ± 0.044,which were significantly lower than those in control group 1.020 ±0.217 and negative siRNA 15 nmol/L group 0.900 ±0.475,and negative siRNA 30 nmol/L group 0.938 ± 0.327 (P ＜0.05 ).Western blotting analysis showed that the level of DNMT1 protein of DNMT1 siRNA group was also lower than those of negative siRNA and control groups.DNMT activity in DNMT1 siRNA15,30 nmol/L groups was 0.364 ± 0.124and 0.250 ± 0.072,which were significantly lower than those in control group 0.931 ± 0.065and negative siRNA group 0.665 ± 0.055 and 0.472 ± 0.040.DNMT activity was positively correlated with DNMT1 mRNA expression ( r =0.69,P ＜ 0.01 ).DNMT1 RNA interference decreased 8 methylated CpG sites of hMLH-1 to 1 site.Concluslons DNMT1siRNA can specifically inhibit the expression of DNMT1 gene of PaTu8988 and DNMT activity,and can decrease methylated CpG sites of hMLH-1 gene.

Objective To investigate the expression of DNMT3b mRNA and microRNA-29b (miR-29b) in pancreatic cancer cells and analyze their relationship.Methods Real-time RT-PCR method was used to detect the expression of DNMT3b mRNA and miR-29b in five pancreatic cancer cell lines ( PANC1,BxPC3,CFPAC,AsPC 1,Capan 2 ) and the relationship between DNMT3b mRNA and miR-29b expression was analvzed by pearson linear correlation method.Results The expression of DNMT3b mRNA in PANC1,BxPC3,CFPAC,AsPC 1,Capan 2 were 0.497 ±0.184,0.420 ±0.168,0.439 ±0.217,0.122 ±0.111 and 0.731 ±0.387,while the expression of miR-29b were 0.745 ± 0.596,0.797 ± 1.000,0.464 ± 0.430,1.836 ± 1.623 and 0.216 ± 0.335.The expression of DNMT3b mRNA was negatively correlated with the expression of miR-29b (r =-0.922,P =0.026 ).Conclusions Both DNMT3b and miRNA29b are involved in the carcinogenesis of pancreatic cancer,and they are negatively correlated.

Objective To observe whether the intravenously transplanted homologous bone marrow mesenchymal stem cells (MSCs) can migrate to the impaired pancreas tissue in the rats with acute necrotizing pancreatitis (ANP). Methods MSCs were isolated from bone marrow of male Sprague-Dawley (SD) rats and adhered to the culture plate in vitro. Female rats were divided randomly into 3 groups:normal transplantation group, ANP transplantation group, ANP group with 10 rats in each group. ANP was induced by intraperitoneal injections with L-arginine. Both transplantation group received MSCs infusion through tail vein. 72 h later, the rats were sacrificed, the pancreas, heart, liver and kidney tissues were harvested, and the morphological changes were examined and scored, the characteristics of migration of MSCs to pancreas were detected with the expression of sry gene of Y chromosome by using chromogenic in situ hybridization (CISH). Results Rapid proliferation occurred in isolated MSCs after culture for 3 ～ 5 days and colonies were formed. After 3 generations, CD29 + CD44 + CD45-cells accounted for over 95% of all the cells. There ware massive tissue necrosis, inflammatory cells infiltration in the pancreas of ANP group, the pathological score was 10.31 ±0. 85, which were significantly higher than that in ANP transplantation group (7.30 ±0.79, P ＜ 0.05). Sry gene could be detected in the pancreas, heart, liver and kidney tissues. In addition, scattered distributed sry positive cells were observed in the normally transplanted pancreatic tissue, lots of sry positive cells were observed in the ANP transplanted pancreatic tissue, and they were located in the most injured areas.Conclusions The inflammatory pancreatic tissue has the ability of recruiting MSCs in vivo, which can alleviate local inflammation.