Our previous investigation have demonstrated that multiple genes alterations, such as deletion of Rb, p53 and p16 gene, point mutation of H-ras gene were detected in cell line and solid tumor of human gastric cancer. We have transfect-ed the independent construct containing Rb, p53, p16 and expression of H-ras antisense RNA respectively into human gastric cancer cell line, and we have analyzed the biological properties of several independent transfectant cell lines, which express exogenous Rb, p53, p16 and H-ras antisense RNA respectively. The cell growth ability was inhibited by introduction of p53 and H-ras antisense RNA, and tumorigenicity also suppressed significantly by p53, p16 and H-ras antisense RNA. These results indicated that alterations of p53, p16 and H-ras gene were involved in human gastric car-cinogenesis.

Objective To investigate the effect of the heroin addicts on rat's thyroid C cells, the secretion of calcitonin(CT) and serum FT_3, FT_4, TSH. Methods Adulthood 55 male SD rats were randomly divided into normal control group(NCG), saline control group(SCG) and heroin dependence group(HDG). Heroin-dependent rat models were set up by the way of subcutaneous injection of heroin and the thyroid glands were excised on the 10th, 17th, 24th, 31st, and 38th days after models were set up. Tissues were assessed by immunohistochemical SABC method, cell counting, image analysis method and chemiluminescence techniques. ResultCompared with the normal control group(NCG)and saliane control group( SCG), the immune staining intensity was weakened;the number of CT positive cells was reduced(P<0.05);the average gray value was significantly higher(P<0.05) and showed a gradual increase in the CT positive cells of heroin dependence group(HGD). The concentration of TSH in HDG was not statistically significant as compared with the NCG. The concentration of FT_3 in HDG decreased gradually on the 10th day and the 17th day as compared with the NCG.(P<0.05). The concentration of FT_4 in HDG increased gradually on the 24th day and the 38th day as compared with the NCG.(P<0.05). Conclusion During heroin dependence period, the number and functional of CT positive cells has decreased. The changes of concentration of FT_3 and FT_4 suggest that the function of thyroid gland has changed.

Point-of-care testing ( POCT ) is expanding rapidly worldwide due to its simplicity and rapid testing.At present , POCT has mainly focused on detection of proteins ( antigen/antibody ) and small molecules based on immunological assay and dry chemical technology.In the past decade , rapid diagnostic assays for nucleic acid have quickly progressed.Some nucleic acid-based POCT products have been developed and approved by US FDA.Now this article discusses the advances in the field of rapid nucleic acid testing including some new technologies and their applications.As a new area of in vitro diagnostics , POCT for nucleic acid is worthy of our attention.

Objective To explore the changes of the expression of islet amylodi polypeptide ( IAPP ) and somatostatin( SS) of islet in type 1 diabetes mice, and the mechanism of the expression changes .Methods We established the diabetes model in C57BL/6J mice by low-dose streptozotocin ( STZ) injection.The excisions of the pancreas tails removed on the 3th, 7th, 10th, 14th, 21th and 28th day.Tissues were assessed by immunohistochemical SABC, immunofluorescence in the study .Results 1.Numerical density on area ( NA ) of IAPP positive cells in experimental group (EG) decreased since the 3th day, but average absorbance increased since the 7th day.2.NA of SS-IR cells in EG increased since the 3th day, and average absorbance increased since the 7th day.3.The results of immunofluorescence double staining showed that , IAPP and SS could coexpression in part of cells in islets .Conclusion The number of IAPP positive cells in type 1 diabetes is decreased , but the immunoreaction increased .Immunoreaction and number of SS positive cells increase .Both of them are involved in the pathogenesis of type 1 diabetes.

Objective: To study the effects of Carisolv caries removal method on dentin bonding strength. Methods:Thirty extracted human third molars with moderate occlusal caries were used. Each molar was split into two parts, one part was prepared by Carisolv method and another was prepared by the low-speed burs. Then samples were randomly divided into three groups. Three adhesive systems were used: Prime&Bond NT +Dyract AP compomer、Uni-Etch +One-step plus+Renew resin composite and Prompt-L-Pop +Z100 resin composite. Microtensile bonding strength(MTBS) of the three adhesive systems were tested. Results:The MTBS of the three adhensive systems were (17.22?7.95) MPa, (25.40?8.44) MPa, (17.66?8.33) MPa in Carisolv group, and were (16.01?7.43) MPa, (23.45?7.55) MPa, (16.26?7.97) MPa in burs group. There was no significant difference between the two caries removal methods.Conclusion:Carisolv caries removal method has no side effects on dentin bonding strength of the three adhesive systems.

Both indirect fluorescent antibody test (IFAT) and immunoenzymatic staining technique(IEST) were used as methods for the comparable detections of 200 cases of patients with schistosomiasis japonica and 100 healthy individuals. The average positive rate in schistosomiasis cases is 99% with both tests, while the false positive rate in healthy individuals is 5% with the former and 3% with the latter. When 322 cases of other parasitic infections and patients with medical diseases were tested by IFAT and IEST, cross-reaction was observed only in clon-orchiasis, fasciolopsiasis and paragonimiasis, 4-6% with IFAT and 0-4% with IEST respectively. 87.6-93.7% showed negative reaction to both tests in schistosomiasis patients during different stages after treatment. It is considered that IFAT and IEST are effective means of serological diagnosis of schistosomiasis japonica, while IEST can be applied suitably in tbe fields for practical purposes.

Objective To analyze the causes of clinical misdiagnosis of solid pseudopapillary tumor of pancreas (SPTP),and recommend the countermeasures with a combination of pertinent literature.Methods The clinical data of 10 cases of SPTP with misdiagnosis were retrospectively analyzed.There were 9 women and 1 man,and the average age was 29.3 years old.The clinical symptoms were nonspecific.Results All patients received surgical treatment,and the correct diagnosis was made according to the pathology after surgery.All patients were followed up,and no recurrence or metastasis was found.Conclusions SPTP is a rare disease in clinic.Sufficient understanding in the clinical features and imaging characteristics can improve the rate of diagnosis before operation.

Objective: To study the effect of Carisolv in caries removal on dentin bonding surface.Methods:24 extracted third molars with moderate carious were randomly divided into four groups. Each cavity was split into two parts, one part was prepared by Carisolv and the other by high-speed bur. Then samples were processed as follows: samples in group A were not treated, those in group B were treated with 320 ml/L phosphoric acid, SEM was used to observe the morphology of dentin surface of the samples in group A and B. Samples in group C were restored with Dyract AP and those in group D with resin for the observation of the microstructure of dentin-filling bonding interfaces.Results:In group A, rough surface without obvious smear layer was exhibited and dentinal tubules were clearly open after Carisolv preparation; after bur preparation, dentin surfaces were covered with a thick smear layer and no opening of tubules was visible. In group B, after treatment with 320 ml/L phosphoric acid, the smear layer was removed and dentinal tubules were exposed after either Carisolv or bur preparation, but tube stoppers were visible in the samples prepared by bur. In group C, resin tags were observed only in the samples after Carisolv preparation. In group D,dentin surfaces and lengths of the resin tags did not show remarkable difference after Carisolv or bur preparation, but more lateral branch connection between resin tags appeared in the samples prepared by Carisolv than by bur.Conclusion:The dentin prepared by Carisolv favors bonding between dentin and resin/compomer and has the advantage of restoring with compomer.

Objective To observe the growth characteristics and multi-time dynamic contrast-enhanced MR(DCE-MR)findings of rabbit VX2 liver tumor on MR imaging, and to provide a reliable basis for the values of MR in assessment of non-surgical treatment effect of rabbit VX2 liver tumor.Methods 10 rabbit VX2 liver tumor models were established by liver tissue embedding through laparotomy under direct vision and DCE-MRI scaning was performed at the 2nd,3rd,4th and 5th week after establishment.The tumor volume (V)and tumor growth rate (TGR)were calculated at different time points and the signal characteristics were analyzed on MR imaging;then all the rabbits were excuted and HE staining were performed to observe the cancer cells in different places with microscope.Results The TGR at the 3rd week after establishment (404.16%±114.64%)was significantly higher than that at the 4th week (223.49%±65.90%)(t=3.417,P<0.05).The tumors with well-boundary were rim-like enhanced significantly and the central parts were not enhanced on DCE-MR imaging,and the parts between the edge and centre of tumors were heterogeneously mild enhanced. The HE staining results showed that 6 cases of tumor were squamous cell carcinoma and the cells were distributed densely in the edge,the cancer cells and necrosis were distributed equally in the parts between the edge and centre of tumors and the centre of tumors were necrosis parts.Conclusion The rabbit VX2 liver tumor grows rapidly at the 3rd week after establishment, and its histological features can be better reflected by DCE-MRI.

Objective To explore the effects and the underlying mechanisms of inhibiting three kinds of DNA methyltransferases(DNMT1,DNMT3a and DNMT3b) on the re-expression of cancer/testis antigen(CTA) in hepatic cells.Methods Transient transfection of HepG2 cells with siRNA was targeted against DNMT1,DNMT3a and DNMT3b(DNMT1+3a+3b),DNMT1 and DNMT3a(DNMT1+3a),DNMT1 and DNMT3b(DNMT1+3b),DNMT3a and DNMT3b(DNMT3a+3b),respectively.The other batch of cells was treated with 5'-aza-deoxycytidine(5-aza-dC) as positive control.Real-time PCR and Western blotting were used to detect the expressions of DNMTs and CTAsm,and the promoter methylation of partial CTA genes was detected with methylation specific PCR(MSP).Results Expressions of DNMT1,DNMT3a and DNMT3b declined significantly after siRNA interference in HepG2 cells.Two CTAs,CT10 and SSX1,re-expressed in the cells transfected by DNMT1+3a and DNMT1+3b.MAGE1 and MAGE3 were equally expressed in all cells despite been transfected or not.Demethylation occurred in the promoter region of CT10,while the promoter region of MAGE1 was in a state of unmethylation.Conclusions In HepG2 cells,CTA promoter can be demethylated via interference of DNMTs,which may lead to the re-expression of CTA that was originally unexpressed due to methylation.