Objective　To investigate p16 gene expression in salivary adenoid cystic carcinoma (ACC) and the relation between p16 gene expression and lung metastasis. Methods　p16 gene protein was detected in 36 cases of ACC by ABC immunohistochemical method. Results　58.3 % (21/36) cases showed positive staining. Higher incidence for positive staining was found in ACC without lung metastasis 76 % (19/25) than those with lung metastasis 36.6 % (4/11) with remarkable statistical difference. Expression of p16 was correlated with the P-TNM stageing (P＜0.05), but was not with pathologic pattern (P＞0.05). Conclusion　The p16 gene may play an important role in suppressing the expression of metastatic potential in human salivary ACC.

Objective To investigate the relationship between single nucleotide polymorphism (677C→T) of methylenetetrahydrofolate reductase and Alzheimer′s disease(AD) in south China Han people. Methods By applying polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP), MTHFR 677C→T mutation was detected in 45 AD patients and 48 healthy controls. Results The frequency of MTHFR 677C→T mutation of patients showed no significant difference to that of healthy controls (P > 0.05). There is no statistic significance between AD group and controls in C, T gene frequency(P>0.05). But T gene frequency is higher in AD group than in control group. Conclusion MTHFR C 677T is not the pathogenic factor for AD, but could have some effects on AD.

Objective To study the impact of TDGF-1 gene silience by small interfering RNA(siRNA)on the invasion and migration of human breast cancer cell. Methods 3 siRNA fragments were designed according to the characteristic of TDGF-1 gene sequence and the most appropriate siRNA was selected by fluorescence real-time quantitative RT-PCR method. After the human breast cancer cell line MDA-MB-468 was transfected by the selected TDGF-1 siRNA, mRNA and protein of TDGF-1 were determined by real time quantitative RT-PCR and western blot respectively. The migration and invasion ability of the cancer cell were evaluated by wound-healing assay and Boyden chamber model respectively. Results siRNA could down-regulate the level of mRNA and protein of TDGF-1 in a dose-and time-dependent manner. In vitro experiment showed that TDGF-1 siRNA transfection can effectively inhibit the clonal growth, invasion and migration of breast cancer cell in a dose-dependent manner. Conclusions TDGF-1 gene may play an important role in the migration and invasion of human breast cancer cells. siRNA transfection can inhibit the invasion of human breast cancer cells.

OBJECTIVESr-HA, a new type of hydroxyapatite biomaterial, was implanted into animals to study the bioreaction and character, which would be helpful for the further clinical applications in the future.

METHODSTotally 24 rabbits were divided into 3 groups. The bone defect of 6 mm x 12 mm x 4 mm was made at both mandibular angles of rabbits and Sr-HA of different proportion (10%, 5%, 0) was applied to reform the defects. One group of animals were killed randomly at 1, 3 and 6 months after operation to evaluate the material biological compatibility using anatomic, X-ray examination, histological and ECT methods.

RESULTSThe histological photographs showed that Sr-HA caused little infection around implanted area and, almost was not repulsed by hosts. With the degradation of biomaterial, there was more apparent new bone growth in the area around Sr-HA than that around HA and some ossification can be found in soft tissue nearby. Also a tight osteointegrity was gradually got after the operation, according to the results of X-ray and, the border between Sr-HA and bone was hardly discovered at the 6th month after the operation. A more obvious nuclide assembling was observed at the side of Sr-HA by ECT images. With the biodegradation of Sr-HA, more new bone was intruded into the spare space of the biomaterial.

CONCLUSIONSr-HA has better biocompatibility and higher biodegradation than that of pure HA. It holds an excellent osteoinductivity and fair osteoconductivity to some degree too. So a more satisfying effect of bone defect rehabilitation was gained with the increasing new bone depositing in the free space of the material, when it degraded gradually.

Animals ; Biocompatible Materials ; Biodegradation, Environmental ; Bone Substitutes ; Hydroxyapatites ; chemistry ; pharmacology ; Implants, Experimental ; Mandible ; surgery ; Osteogenesis ; physiology ; Rabbits ; Strontium ; chemistry ; pharmacology

ObjectiveTo evaluate the efficacy and safety of endoscopic submucosal dissection (ESD) for precancerous lesions and early cancer at gastroesophageal junction (GEJ) by comparing endoscopic mucosal resection (EMR) with ESD.MethodsData of patients with GEJ precancerous lesions or early cancer,who received EMR ( n =51 ) or ESD ( n =28) were reviewed to compared the en bloc resection rate,R0 resection rate,operation time,complication and recurrence rate between 2 methods.ResultsEn blcc resection and R0 resection rates of ESD group (92.9％,78.6％ respectively) were significantly higher than those of EMR group (45.1％,43.1％ respectively).Local recurrence rate in ESD group (3.6％,1/28) was significantly lower than that of EMR group ( 19.6％ ).Complications including perforation,delayed hemorrhage,stricture were not significantly different between EMR and ESD groups.Mean operation time of ESD group (64.3 ±27.1 min) was significantly longer than that of EMR group (27.6 ± 14.1 min)(P ＜0.05).ConclusionESD,with a higher cure rate and en bloc rate and a lower local recurrence rate,is superior to EMR for precancerous lesions and early cancer at GEJ.

ObjectiveTo study the effects of tumor-associated calcium signal transducer-2 (TROP-2) gene small interfering RNA(siRNA) on adhesion and invasion of human breast cancer cell. MethodsReal time PCR was used to evaluate the TROP-2 mRNA of seven human breast cancer cell lines Bcap-37 ,LCC1 ,MCF-7 ,MDA-MB-231,MDA-MB-435, MDA-MB-468 ,and ZR75-1. The cell line of TROP-2 highest expression was transfected with different dose of TROP-2 siRNA. The expression of TROP-2 mRNA and protein were determined by Real-time quantitative PCR and immumoflurescence method. The cell adhesion was evaluated by MTT assay,and invasion was exmined by hoyden chamber,respectively. Results Cell line MCF-7 showed the highest elevation of TROP-2 mRNA in seven breast cancer cell lines. The results from real-time quantitative PCR and immumoflurescence method showed that TROP-2 mRNA and protein reduced in time-and dose-dependent manners( P ＜ 0.01 ;P ＜ 0.01 ). The adhesive rate of siRNA groups(5 nM,10 nM,and 20 nM)was(52.9 +2.5)％ ,(25.6 ±2.3)％, ( 12.8 +2.2)％ (P ＜0.01 ) ,respectively.The transwell results showed that the invasion cells was(78 ± 17), (39 ± 15), ( 19 ± 16), ( 136 +25 ) and( 139 ±21 )in different groups(5,10,20 nM siRNA,and controls) ,respectively(P ＜0.01). ConclusionTROP-2 gene might play an important role in adhesion and invasion of human breast cancer cell. siRNA targeted TROP-2 could effectively inhibit adhesion and invasion of human breast cancer cell.

ObjectiveTo investigate the therapeutic effect of human umbilical cord mesenchymal stem cell-paracrine substance on fulminant hepatic failure (FHF) rat, and to study the effect on liver function and hepatocyte proliferation. MethodsMesenchymal stem cells(MSCs)were separated from human umbilical cord, and surface makers of cells were detected by flow cytometry. Human umbilical cord mesenchymal stem cells-conditioned medium(MSC-CM) was prepared. FHF rat model was induced by intraperitoneal injection of D-galactosamine and they were randomly diveded into three groups: MSC-CM group, NS group, PHGF group. 24 h later, 1 ml MSC-CM, 1 ml 0. 9% NaCl solution and lml PHGF solution was injected into the tail vein of MSC-CM, NS, and PHGF rats, respectively. In each group (n=8 per group), blood samples were collected at 12, 24, 36, and 60 h after treatment from inner canthus for analysis of blood ALT and TBIL levels. We used five rats per group for tissue collection after sacrifice at 36 h after treatment and 10 animals per group for survival analysis. PCNA immunohistochemical staining was used in the sections of liver tissue to detect hepatocyte proliferation. Results24 h after treatment, the levels of ALT and TBIL in the MSC-CM and PHGF groups were lower than those in the NS group(P＜0. 05), but there was no significant difference between the MSC-CM and PHGF groups. There were more PCNA-positive hepatocytes in the MSC-CM and PHGF groups than in the NS group(P＜0.01), but there was no significant difference between MSC-CM and PHGF group. Survival analysis found that the survival rate of rats in the MSC-CM and PHGF groups was higher than that of rats in the NS group (P=0. 049), but there was no significant difference between the MSC-CM and PHGF group. ConclusionsThe paracrine substance of human umbilical cord mesenchymal stem cells can stimulate hepatocyte proliferation and improve liver function of FHF rats, potentially creating a new avenue for the treatment of FHF.

The serum TSH levels of 107 infants with subclinical hypothyroidism (SH) were > 20 mIU/L after 1-8 check-up, along with FT4, TT4, within low normal range. After given small dosage L-T4, for 4 weeks, blood TSH level obviously descended while FT4, TT4, ascended (all P <0.01). Seven cases of thyroid hypogenesis and 7 strumas were found by ultrasonography. It seems appropriate to use dosage of 3-4 μg·kg·-1·d-1 L-T4 in treating SH.

Objective To study effects of polo-like kinase-1(PLK1)small interfering RNA(siRNA)on proliferation and apoptosis of undifferentiated human thyroid cancer cells.Methods 5 PLK1 siRNA(S1,S2,S3,S4 and S5)were constructed and used to transfect human thyroid cancer cell line ARO.RT-PCR was employed to pick out the most effective siRNA,which was then used to transfect ARO cell.RT-PCR and western blot were used to detect PLK1 expression in thyroid cancer cells,which were divided into different groups.MTT assay was performed to examine the effects of PLK1 siRNA on thyroid cancer cells in all groups.Apoptosis of thyroid cancer cells was observed by caspase-3 activity and TUNEL.Results All the 5 siRNA down-regulated PLK1 mRNA expression.among which S4 showed the best effect.S4 transfection could obviously inhibit proliferation of thyroid cancer cells in dose and time dependent manner.Compared with control groups,caspase-3 activity of cancer cells in s4 transfeeted group increased significantly.The effect of S4 transfection was dose and time dependent.TUNEL results showed apoptosis of cancer cells transfected by S4 siRNA was obvious and apoptosis of cells was dose-dependent.Conclusions PLK1 may play an important role in proliferation of undifferentiated thyroid carcinoma.PLK1 siRNA transfection can inhibit proliferation of throid cancer cell through apoptosis induction.

Objective To study the effects of midkine(MK)gene small interfering RNA(siRNA)on adhesion and invasion of human breast cancer cells.Methods Real time PCR was used to evaluate MK mRNA expression in 7 human breast cancer cell lines Bcap-37,LCCI,MCF-7,MDA-MB-231,MDA-MB-435,MDA-MB-468,and ZR75-1.The cell line in which MK expression was the highest was transfected with different doses of MK siRNA.The expression of MK mRNA and protein was determined by real-time quantitative PCR and immunoflurescence staining.The cell adhesion was evaluated by MTT assay and invasion was examined by Boyden chamber method.Results Cell line MCF-7 expressed the highestlevel of MK mRNA in the 7 tested breast cancer cell lines.After being transfected with MK siRNA,MK mRNA and protein level of MCF-7 decreased in timeand dose-dependent manners.The adhesive and invasive ability of MCF-7 cell transfected with MK siRNA decreased in a dose dependent manner(P<0.01,P<0.01).Conclusions MK gene might play an important role in adhesion and invasion of human breast cancer cells.siRNA transfection could effectively inhibit adhesion,migration,and invasion of human breast cancer cell.