In this paper the protective effect and facillitating reconverting effect of polypeptide from chlamys farreri (PCF) on thymocytes irradiated by 60 Co ? ray were studied using the MTT chromatometry .The results showed that:(1)the damaged extents of thymocytes were increased with the radiative intensity of 60 Co ? ray elevated at the range of 3GY to 9GY compared with that in no-exposure to 60 Co ? ray group.(2)PCF could reduce 60 Co ? ray damage on thymocytes with dose dependence .In the 0.25%~4% concentration range the higher concentration of PCF the stronger protective effects of it ,but the protective effect of PCF at the concentration below 0.5% disappeared while the radiative intensity of 60 Co ? ray was at 9GY.(3)PCF could facilitate the renovation ability of thymocytes after exposure 60 Co ? ray for two hours .And only 2% concentration of PCF showed the facilitating repair process of thymocytes after radiated by 60 Co ? ray for 7 hours .(4) PCF could decrease the activity and facilitate the death of the dying thymocytes after exposure 60 Co ? ray for 19 hours. The results suggested that the protective effect and facilitating repair effect of PCF on the thymocytes damaged by 60 Co ? ray may be mediated by the antisuperoxidation of PCF.

BACKGROUND: Studies have demonstrated that trehalose possesses protective effects on cyropreserved sternum. But the mechanism of action remains poorly understood. OBJECTIVE: To investigate the effects of trehalose on bcl-2 and bax mRNA expression in cryopreserved sternum. METHODS: Four groups of freshly prepared solution were used: low-potassium dextran (LPD), LPD + dimethyl sulfoxide (DMSO), LPD + trehalose, LPD + DMSO + trehalose. Rat sternum was cut and then immediately cryopreserved in the tubes containing each group of solution. Fresh rat sternum tissue and 4 groups of samples cryopreserved for 120 days were taken and bcl-2 and bax mRNA expression in fresh and cryopreserved sternum was detected using reverse transcription-polymerase chain reaction.RESULTS AND CONCLUSION: bcl-2 mRNA expression in the LPD + trehalose group was significantly higher, but bax mRNA expression was significantly lower, than in the LPD, LPD + DMSO groups (both P < 0.01). LPD + DMSO + trehalose group showed highest bcl-2 mRNA expression and lowest bax mRNA expression, which were basically similar to fresh bone tissue (P > 0.05). These findings indicate that trehalose may protect cell activity in cryopreserved sternum by enhancing bcl-2 mRNA expression and inhibiting bax mRNA expression, and trehalose together with DMSO shows better protective effects.

Objective To observe the changes of serum myostatin (MSTN) level in patients with gastric carcinoma-associated cachexia and to investigate the relationship between MSTN and tumor necrosis factor α (TNF-α) preliminarily.Methods Eighty patients with gastric cancer were divided into two groups based on their Patient-Generated Subjective Global Assessement (PG-SGA) scores:gastric carcinoma-associated cachexia group (GCC group,32 cases; PG-SGA stage C) and gastric carcinoma non-cachexia group (GCNC,48 cases; PG-SGA stage A + B).The serum MSTN and TNF-α levels were measured by enzyme linked immunosorbent assay,and relevant parameters including height,weight,albumin,hemoglobin,and C-reactive protein were also recorded before operation.Eighty healthy adults were chosen as the control group.Results The serum MSTN level in the GCC group [(1.36 ±0.50) μg/L] was significantly higher than that in the GCNC group [(0.91 ±0.49) μg/L; x2 =14.67,P =0.00],whereas the serum MSTN level in the GCNC group was significantly higher than that in the control group [(0.70 ± 0.37) μg/L; x2 =36.45,P =0.00].Serum MSTN level was not correlated with TNF-α in the GCC group (r=0.18,P=0.31),GCNC group (r=0.08,P=0.58),or control group (r=-0.16,P＝0.16).Conclusions Serum MSTN level is elevated in patients with gastric carcinoma-associated cachexia.However,it is not correlated with serum TNF-α.

Background The scarring of conjunctival filtering blebs after glaucomatous surgery is a leading cause of operation failure.Exploring the balance between matrix metalloproteinase-2 (MMP-2) and tissue inhibitor of matrix metalloproteinase-2 (TIMP-2) in conjunctival filtering bleb is very important for the study on pathogenesis of postoperative scarring.Objective This study was to evaluate the role of MMP-2 and TIMP-2 in wounding healing of subconjunctival tissue after filtering surgery in rats.Methods Sixty-three clean male SD rats were divided into normal control group and postoperative 1-day,3-day,5-day,7-day,14-day and 28-day group.The drainage tube was monocularly implanted into the anterior chamber of the rats to establish the filtering surgery models,and the operative response of the eyes was examined under the slit lamp microscope.The animals were sacrificed in corresponding time points,and the frozen sections of eyeballs were prepared,and the expressions of MMP-2 and TIMP-2 in conjunctival and subconjunctival tissues were detected using immunofluorescence technique.Western blot was employed to assay the dynamic expressions of MMP-2 and TIMP-2 proteins in conjunctival and subconjunctival tissues in different groups.The use and care of the rats complied with the Instruction Notions with Respect to Care for Laboratory by State Ministry of Science and Technology.Results Filtering blebs were formed in all the operated eyes 1 day after surgery and remained for 7-17 days,with the average survival time of 12 days.Western blot assay revealed that the expression levels of MMP-2 protein in the filtering blebs of the normal control group were 121.67 ±4.37,and the expressions were gradually elevated from the postoperative 3-day group (183.67±5.61) until the postoperative 7-day group (230.50±8.48) and then gradually declined till the postoperative 28-day group (172.33 ± 8.43),showing a significant difference among the groups (F=280.18,P＜0.05).In addition,the expression levels of TIMP-2 protein in filtering blebs of the normal control group were 102.50 ±6.25.The expression levels were gradually raised in postoperative 3-day group (162.67±7.00) and peaked in the postoperative 5-day group (232.00± 11.03),and then the levels gradually reduced till the postoperative 28-day group (150.50±6.41),with a significant difference among the groups (F =145.34,P ＜ 0.05).Immunofluorescent staining showed that MMP-2 and TIMP-2 were weakly expressed in the conjunctival epithelium of the normal rats,while in the operated rats,strong fluorescence for MMP-2 and TIMP-2 was seen in both conjunctival epithelium and subconjunctival tissues of filtering blebs.Conclusions The expression trends of MMP-2 and TIMP-2 in the filtering blebs are consistent to the fibrosis process of conjunctival tissue,indicating that MMP-2 and TIMP-2 participate in the scar formation of conjunctival filtering bleb after glaucoma filtering surgery.

Objective:To evaluate the effect of semiconductor lasers irradiation after routine root canal preparation on root cannal seal.Methods:60 Single-rooted freshly extracted human teeth were randomly divided into 6 groups(n=10).The crowns were removed at the cementoenamel junction and the roots were endodontically prepared with conventional methods.The roots in groups A and B were irradiated with 1 W semiconductor laser for 20 s,in group C and D were ultrasonically washed for 1 min,in group E and F without any treatment were used as the controls.Then all the roots were filled by vertical condensation of warm gutta-percha.The root cannal seal was evaluated with microleakage measurement.The data was analyzed by ANOVA.The teeth of group B,D and F were sectioned and examined under scanning electron microscope(SEM).Results:The microleakage(mm) of group A,C and E was 1.70±0.82,2.02±0.40 and 4.56±2.72 respectively(A vs E,P<0.01;C vs E,P<0.05;A vs C,P>0.05).SEM observation showed the melting,narrowness or closure of most dentinal tubules in group B,past and/or gutta-percha in the most dentinal tubules of group D.Conclusion:Semiconductor laser irradiation prior to root cannal filling can promote the effects of cannal seal.

Sulfated polysaccharide from Porphyra haitanensis showed inhibitory effect on the lipid peroxidation in vitro. In the present study, the changes in the antioxidative enzyme activity, lipid peroxidation, and total antioxidative capacity (T-AOC) in different organs after 60 Co irradiation were detected in mice by using biochemical methods. Increased endogenous lipid peroxidation and decreased contents of T-AOC as well as decreased activities of super-oxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were observed in mice after 60Co irradiation. Intraperitoneal administration of polysaccharide fraction F2 significantly decreased the lipid peroxidation. F2 treatment increased T-AOC and the activities of SOD and GSH-Px in all organs tested in 60Co irradiated mice. It is concluded that the sulfated polysaccharide fraction F2 from Porphyra haitanensis can be used in compensating the decline in antioxidative capacity arising from radiotherapy and thereby reduced the risks of lipid peroxidation.

Objects To evaluate the immunosuppressive effect of marine preparation JLB extracted from Argopecten irradisus on aortic valve allograft durability. Methods The aortic valve homograft heterotopically allografted onto abdominal aorta from SD to Wistar rats. Then Wistar rats were divided into 2 groups. Test group was treated with JLB (0.5g?kg~ -1). The other group served as control. The rats were sacrificed in batches at 2, 4, 8and 12 weeks postoperatively. Blood samples and AVH were obtained for accessing the expression of CD25, CD71 and CD28. Results The expression of CD25, CD71 and CD28 in test group decreased more than that of control group at early stage of the transplantation. Conclusion JLB treatment can inhibit immune response at early stage after the transplantation.

Objective To explore the experiment condition and method for the application of in vitro in vasive Transwell chamber and to observe muscarinicreceptor stimulant and muscarinicreceptor antagonist's influence to cholangiocarcinoma's invasiveness.Methods Two hundred microliter cell suspension of various concentrations(0.5×105/mL,1.0×105/mL,1.5×105/mL and 2.0×105/mL)was added into the upper chamber of the Transwell chamber,and the cells were allowed to penetrate the matrigel for 12,18,24and 48 hours respectively.The numbers was gotten as the invasive cells on the under surface of the membrane.After optimal cell concentration and time were gotten,pilocarpine of various concentrations(0 mmol/L,0.1 mmol/L,0.3 mmol/L and 0.5 mmoL/L)was added into the upper chamber of the Transwell chamber,then the cells on the matrigel were stained and counted.So did the cells when atropine of various concentrations(0.01 mmol/L,0.01 mmol/L,0.05 mmoVL and 0.1 mmol/L)were added into the upper chamher of the Transwell chamber in according to pilocarpine of various concentrations(0 mmol/L,0.3 mmol/L,0.3 mmol/L and 0.3mmol/L).Results With the increase of the time and cell concentrations，the cells couts that penetrated the matrigel increased，while the increase tended to he stable when the culture time exceeded 36 hous and the cell concentration Was over 1.0×105/mL.By adding pilocarpine,there were significant differences between the control and experimental groups(P＜0.05)，but there were no significant differences in experimental groups with various concentrations.There were no significant differences in blank group and experimental groups with atropine added(P＞0.05).When added pilocarpine and atropine,there were significant differences between blank and experimental groups(P＜0.05)，but there were no significant differences in experimental groups with various concentrations.Conclusions Thirty-six hours as invasive time,and one cell concentration 1.0 × 105/mL were optimal to test invasion abilities of cholangiocarcingma cells to different medicines or reagents.There is the possibility that museariniereceptor exists in cholangiocarcinoma cells，and may play an important role in cholangiocarcinoma's invasiveness and metastasis.

Objective To evaluate the expression of substance P (SP) and caltenin gene related peptide (CGRP) in esophagueal mucosa from patients with non-erosive gnstroesophageal reflux disease (NERD) and reflux esophagitis (RE) and to explore their role in the development of NERD. Methods Fif-ty-one patients with typical symptoms of gnstroesophageal reflux disease (GERD) were evaluated with reflux disease questionnaire (RDQ), PPI test, endoscopy and 24hr esophageal pH monitoring. The patients were then divided into RE group (n = 21), NERD group with acid refluux (NERD+, n = 12) and NERD group without acid reflux (NERD-, n = 18) according to the evaluation results. The expression of SP and CGRP in esophagus mucosa from these patients and 10 healthy control subjects were assayed by immunohistochemis-try, and the stain positive index (PI) was calculated by Color patho-image analysis software and compared. Results The PIs of SP and CGRP in NERD- group were 96.77±31.74 and 24.76±29.15, respectively, which were significantly higher than those of NERD+ group (73.64±31.38, 9.78±10.30, respectively, P < 0.05), RE group (67.56±34.62, 9.61±6.20, respectively, P < 0.05) and control group (59.82± 46.15, 8.64±12.12, respectively, P < 0.05). Conclusion Expressions of SP and CGRP in esophagus mucosa from NERD patients without detectable acid reflux are significantly increased, they may play an im-portant role in esophageal visceral sensitivity.

Objective To investigate the effect of carboxyl methyl chitosan on hypertrophic scars by establishing a hypertrophic scar model on the ventral side of rabbit ears.Methods Full-thick-ness excisional wounds,1 cm in diameter,were made in the ears of 12 adult New Zealand white rabbits,and 123 hypertrophic sears were made in all.Then the rabbits were divided into 3 groups:group A was an experimental group (carboxyl methyl chitosan,500μg/ml),group B was a control group 1 (triamcinolone),and group C was control group 2 (physiological saline).All the scars were injected with drugs on the 30th and 40th days after operation,and then the samples were collected on the 35th and 45th day and analyzed.Results Compared with group C,group A appeared to be flatter,softer,and lighter in color;the area density of fibroblast decreased using HE stain and masson stain (P<0.05),and hydroxyproline content and hypertrophic index were also lower than group C (P<0.05).There were no significant differences of those criteria between group A and group B (P>0.05).Conclusion Injection of carboxyl methyl chitosan into Iocal hypertrophic scars On rabbit ears has similar effects to triamcinolone,and both of them can prevent and cure hypertrophic scars in proliferative stage.