Objective To screen the HBV SPⅡ promoter DNA-binding protein, and to investigate its potential role in the regulation of replication and expression of HBV DNA. Methods By using HBV SPⅡ biotinylated promoter DNA as a selective molecule, the T7 select human liver cDNA library was biopanned and the positive clones were selected. After screening, amplification of positive plaques was performed for inserted DNA fragment and then they were cloned into the pGEM-Teasy vector. Results Four positive plaques were chosen for DNA sequencing. The binding protein of HBV SPⅡ promoter was demonstrated as nicotinamide adenine dinucleotide (NADH) dehydrogenase 4 by BLAST. Conclusion The result suggests that this approach may provide a new tool for the study of replication and expression mechanism of HBV DNA.

The solid pseudopapillary tumor of pancreas (SPT) is a rare pancreatic tumor with low malignant potential. It primarily affects young women. The clinical characteristic is nonspecific, but the pathological characteristic is distinct. The tumor consists of both cystic and solid component. The typical histopathological appearance of SPT is the pseudopapillary structure with a fibrovascular surrounded by several layers of epithelial cells.Only a few SPTs present invasive behaviors. The tumor cells express a wide range of immunohistochemical markers. The pathogenesis is associated with the Wnt signaling pathway, which is changed by β-catenin, Pl20-catenin, adenomatous polyposis coli gene( APC), the cyclin-dependent kinase inhibitors p21 and p27.

A microcapsule is a spherical, with a diameter that can be controlled in the range of 200 -1500 μm and biocompatible semipermeable membrane, which allows the bidirectional diffusion of nutrients,oxygen, secreted therapeutic product, and waste but prevents the penetration of high molecular weight substances from the microcapsule, such as antibodies and immunocytes. In comparison to monolayer culture and multicellular tumor spheroid model, orthotopic injection of microencapsulated tumor cells has uncomparable advantages in cell proliferation, mimicking the in vivo situation, making orthotopic tumor model and distant organ metastases model. Microencapsulated tumor assay has the potential of being widely used for in vitro anticancer drug screening and evaluation of the effects. This article mainly reviews the advantages of microencapsulated tumor assay and its application.

Pancreatic cancer is a highly malignant tumor. Animal models of pancreatic cancer included xenograft models, carcinogen induced models, genetically engineered models. Xenograft models are relatively reliable and feasible, but the growth pattern is different between serve immunodeficienct animals and human beings. Carcinogens induced models simulated the environmental factors to reconstruct the development of pancreatic cancer. But carcinogens could have other biological effects. Genetically engineered models could make the occurrence of pancreatic cancer at the molecular level. But it is difficult to control the transgenic product accurately. No model could meet all the needs of different experiments. It is important to choose a suitable animal model in different experiments.

Objective To evaluate reoperations for benign bile duct strictures after a prewousRoux-en-Y hepaticojejunostomy.Methods Clinical date of 28 patients with previous reconstruction of Roux-en-Y hepaticojejunostomy for benign bile duct strictures were retrospectively analyzed.For data staftstical analysis t-test and stepwise logistic regression analysis were used.Results Reoperative surgery was performed for residual biliary stones with bile duct stricture in 10 cases(35.7%),simple anastomotic stricture of hepaticojejunostomy in 11 cases(39.3%),remained biliary stricture after initial rear in 6 cases (21.4%).anastomotic leakage with duodenal leakage in one case(3.6%).Mode of reoperation:18 cases (64.3%)underwent hepatic lobectomy with Roux-en-Y hepaticojejunostomy,liver splitting approach to Roux-en-Y hepaticojejunostomy in 5 cases(17.9%),right hemihepatectomy in one case(3.6%),resection of anastomotic stenosis involved segment and Roux-en-Y hepaticojejunostomy in one case(3.6%),abdominal drainage and duodenum fistulization and jejunum ostomy in one case(3.6%),choledocholithotomy with T-tube drainage in 2 cases(7.1%);Thirteen patients(46.4%)developed postoperative complications.Conclusion Biliary tract stenosis remains the main cause for reoperation in patients undergoing a faeled reconstruction.Wide and patent biliary tract drainage and reconstruction somenmes necessitate a hepatic lobectomy.

Objective To introduce a new extracapsular approach for thyroidectomy in patients with surgical thyroid disease. Method Clinical data of 104 cases undergoing this procedure were retrospectively analyzed. Results From May 1990 to May 2000, 104 patients underwent either total or subtotal thyroidectomy by extracapsular approach. One patient suffered from postoperative temporary recurrent laryngeal nerve palsy. No morbidity such as postoperative thyroid crisis, hemorrhage leading to airway compression, permanent hypoparathyroidism nor mortality developed. Conclusion The total extracapsular approach for thyroidectomy is safe, less of complication and effective.

Objective To study the effects of drug-containing serum of Ficus Hirta on oxidative damage of spleen lymphocyte due to aging in aged mice; To discuss its mechanism of action.Methods Forty aged mice were randomly divided into control group and high-, medium- and low-dose Ficus Hirta groups. Control group was given 0.9% sodium chloride solution for gavage, while high-, medium- and low-dose Ficus Hirta groups were given 6.6, 4.4, and 2.2 g/kg aqueous extract of Ficus Hirta for gavage. The spleen index was observed for optimum dose in aged mice. The optimum time and dilution of drug-containing serum of Ficus Hirta were confirmed by MTT method in lymphocyte proliferation test. The positive rate of senescent cells, the activity of T-SOD and the contents of MDA and ROS were determined in cellular antioxidant experiment after treated by optimal drug-containing serum for 48 h. Results Compared with the control group, the spleen index was significantly improved in high-, medium- and low-dose Ficus Hirta groups (P<0.05,P<0.01). 20% drug-containing serum of Ficus Hirta cultivated for 48 h had the best effects on lymphocyte proliferation in aged mice. 20% drug-containing serum of Ficus Hirta could significantly decrease the positive rate of senescent cells (P<0.01), improve T-SOD activity and decrease the contents of MDA and ROS (P<0.05,P<0.01).Conclusion The drug-containing serum of Ficus Hirta can improve the proliferative activity of spleen lymphocyte in aged mice and the mechanism of action may be involved in decreasing the positive rate of senescent cells and increasing antioxidant ability of lymphocyte.

Objective:To prepare injectable interferon ?-2b(IFN-?-2b) loaded microsphere and develop a long-acting dosage form.Methods: IFN-?-2b loaded microspheres were prepared with poly(lactic-co-glycolic acid)(PLGA) as carrier material by double emulsion(w/o/w) method and solid in oil in oil(s/o/o) method separately.Physical and chemical characteristics of microspheres(mean diameter,morphology and drug entrapment efficiency) were evaluated;the in vitro release behavior and influencing factors of the microspheres were determined by micro-BCA(bicinchoninic acid) method;and IFN-?-2b stability during encapsulation and in vitro release was evaluated by sodium dodecyl sulfate polyacrylamide gel electropheresis.Results: The 2 types of microspheres produced had good shape and dispersive quality and a drug entrapment efficiency of more than 80%.IFN-?-2b bulk ultrafitration can significantly influence the mean diameter and in vitro release behavior of microspheres prepared by w/o/w method.The accumulated release(within 1 month) of the microspheres prepared by both methods was significantly improved when using PLGA with lower inherent viscosity.SDS-PAGE test showed aggregation of IFN-?-2b with s/o/o method,while there was no difference between the electrophoretic behavior of bulk IFN-?-2b and IFN-?-2b in microspheres prepared by w/o/w method.Conclusion: IFN-?-2b can be encapsulated into injectable microspheres to yield a one-month continuous release by both w/o/w method and s/o/o method.

Objective To study the clinical characteristics and diagnosis of the solid-psendopapillary tumor of pancreas (SPT).Methods The clinical data of 40 SPT from January 1996 to January 2008 were retrospectively analyzed. The average age was (32.9 + 13.6 )years. The average clinical course was (8.6±0.1) months.Clinical symptoms usually included distensible pains and secret anguish in abdomen (60.0%).No jaundice appeared in any case.Results The surgical resection was favorable for the treatment of SPT,which had excellent prognosis.No tumor recurrence were found in those following-up patients. Grossly,the cut surface showed areas of solid and papillary tissue,cystic degeneration,hemorrhage,and necrosis.Pathological features included a combination of solid and cystic components with pseudopapillae formation and degenerative regions without glands.Conclusions SPT has its uniquely clinical and pathological characteristics.Its main diagnosed points are helpful for clinical doctors to make timely diagnosis and reduce the rate of misdiagnosis and mistreatment.

Objective To improve the diagnosis and management of solid-pseudopapillary tumor (SPT) of the pancreas. MethodsTwenty-two SPT patients were retrospectively reviewed and divided into two groups, misdiagnosed group and those with preoperatively correct diagnosis. ResultsAbout one half (46%) SPT cases were misdiagnosed preoperatively. With time SPT tends to invade its capsule resulting in impossibility of radical resection, and increased medical expenses. ConclusionsAlthough SPT is of low degree malignant, and the prognosis after surgical resection is satisfactory, misdiagnosis and preoperative misdiagnosis and inappropriate management still cost the patients increased expenses and inhospital stay.