BACKGROUND:Cancer stem cell (CSC) hypothesis suggests that tumorous clones are maintained by a rare fraction of cells with stem cell proprieties. Several kinds of CSCs of solid tumor have been isolated in recent years. However, there have been fewer studies on the objective existence of bladder cancer stem cells (BCSCs) and on the methods to effectively isolate and identify BCSCs. OBJECTIVE:To investigate possibilities of BCSC existence and of epithelial membrane antigen (EMA) used as a surface marker of BCSC. DESIGN:A control observation experiment. SETTING:Tianjin Institute of Urinary Surgery & Second Hospital of Tianjin Medical University. MATERIALS:This study was performed at the Room for Tumor Immunity of Tianjin Institute of Urinary Surgery (key laboratory for State "211 Project") from March 2006 to July 2007. Nine specimens of human bladder were obtained from patients who received treatment in the Second Hospital of Tianjin Medical University. These specimens corresponded to the diagnostic criteria of low malignant potential papillary urothelial neoplasm and low-grade papillary urothelial carcinoma. Additionally, 40 samples of human low malignant bladder transitional cell carcinomas (BTCC) and 10 samples of normal urothelium that were used for immunohistochemistry were obtained from the patients who received treatment in the Department of Urinary Surgery, Second Hospital of Tianjin Medical University. Written informed consent for the specimen providing was obtained from the patients, and the protocol was approved by the hospital’s Ethics Committee. METHODS:The genes that were differentially expressed between normal urothelium and BTCC were identified through a DNA array assay to preliminarily determine the existence of BTCC. Overpressed stem cell related genes, Bmi-1 and EZH2, were verified by immunohistochemistry. A total of 27 potential surface markers of BCSCs were assayed to determine the location of positive cells. EMA- subsets were obtained through an immunomagnetic bead cell sorting system to analyze their abilities for colony forming, self-renewal and extensive proliferation. MAIN OUTCOME MEASURES:Normal urothelium and BTCC gene expression difference, Bmi-1 and EZH2 protein expression difference between low malignant BTCC and normal urothelium; and experimental results of colony forming. RESULTS:A total of 268 genes (including Bmi-1 and EZH2) that were differentially expressed between normal urothelium and low malignant BTCC were identified through a DNA array assay. The Bmi-1 and EZH2 had been found overexpressed in the low malignant BTCC. Except for EMA, above-mentioned 26 out of 27 potential surface markers were null for isolating BCSCs. EMA- subsets were located in the basal layer and suprabasal epithelial layers of both normal and tumorous urothelium (potential location of BCSCs). EMA- subsets possesed the abilities for colony forming, self-renewal and extensive proliferation. CONCLUSION:The experiment confirms the existence of BCSCs. EMA- might be a surface marker of BCSCs.

Objective To investigate effects of glucose on mesenchymal stem cells(MSCs) proliferation and the possible mechanism. Methods We evaluated the purity of MSCs,established different groups of glucose, detected proliferation by MTT, and analyzed cell cycle and apoptosis by a flow cytometry system. Results The purity of MSCs exceeded 90%.The positive rates of CD44, CD90, CD45, CD34 were 91.92%, 93.38%, 2.23%, 1.05% respectively.Glucose significantly affected MSCs proliferation(P=0.003):11 mmol/L glucose could promote MSCs proliferation, but 25 mmol/L glucose made this effect disappear. High glucose significantly increased the percent of S phase in cell cycle(P=0.002)and the rate of apoptosis(P=0.000). Conclusions Glucose has two-way regulation towards MSCs proliferation, and the balance between cell-cycle arrest and apoptosis could be responsible for this effects

Neurogenic bowel is a syndrome that resulted from the denervation after spinal cord injury (SCI), and may influence the quality of life of SCI patients for the constipation and incontinence. It might be benefit of multidimensional bowel management including nu-trition, medicine and liquid, as well as stimulation, clyster etc. Surgery could be considered if necessary.

Objective: To establish the permanent tooth germ missing animal model for future research on the root resorption of deciduous tooth in the absence of permanent tooth germ. Methods: The permanent tooth germ missing animal model was established by surgical removal of the permanent tooth buds in a male 11-week-old Beagle dog. Root resorption of the deciduous teeth without permanent successors was observed by taking periapical films periodically,and compared with physiological root resorption. Once the sign of root resorption of the deciduous teeth without permanent successors was detected on radiographic films, the animal was sacrificed and the mandibular bone was collected for histological study. Results: Root resorption of the deciduous teeth with the presence of permanent tooth germ started at 20 weeks after birth, while root resorption of deciduous teeth without permanent tooth germ started 26-27 weeks which was significantly delayed. Histological studies showed that a large number of multinucleated giant cells were present on the pulpal surface of the root, while only few of them were seen on the outer surface. Conclusion: The permanent tooth germ missing animal model was successfully established in this study which simulated the case of congenital absence of permanent tooth germ in human. Root resorption of deciduous tooth without permanent tooth germ was significantly delayed than the deciduous tooth with permanent tooth germ.

Objective To detect the expression of PCNA and Ki-67 proliferation antigens in thyroid neoplasms and to study diagnostic value of expression of PCNA and Ki-67 in benign and malignant neoplasms of thyroid. Methods The expression of PCNA and Ki-67 in 76 thyroid neoplasms was examined by immunohistochemical method(EnVision MT ). Results Among the 39 thyroid adenomas(TA), the indices of PCNA and Ki-67 were 0 16?0 09(39/39) and 1 49?1 15(39/39) respectively; Among the 37 thyroid carcinomas(TC), the indices of PCNA and Ki-67 were 0 43?0 31(37/37) and 2 13?1 52(37/37) respectively. The differences of both the PCNA and Ki-67 indices between TA and TC were significant(P

Objective To construct the uItrasound microbubbIes co-carrying recombinant adenovirus containing stromal cell derived factor 1 (SDF-1α) and bone morphogenetic protein 2 (BMP2),and to study the maximum efficiency of carrying adenovirus and the optimum proportion of double gene combined with ultrasound contrast agents.Methods Microbubbles were combined separately with recombinant adenovirus co-expression of enhanced green fluorescent protein and SDF-1α(pAd-EGFP/SDF-1α) as well as red fluorescence protein and BMP2 (pAd-RFP/BMP2) via biotin-streptavidin method,and the maximum efficiency of carrying DNA in microbubbles was detected.Three microbubbles with binary vectors were prepared by blending the two above-mentioned pAd at different ratio (1 ∶1,1 ∶ 2,2 ∶ 1) into the microbubbles.The microbubbles with binary vectors were evaluated though physiochemical properties,fluorescence microscope and flow cytometry to test the carrying rate of DNA in microbubbles.Results There was no significant difference in PH,average diameter and concentrations between targeted microbubbles and control group (P ＞0.05).The carrying efficiency of DNA increased with virus loads in microbubbles,but lowered if further increasing virus amount after reaching saturation.When the proportion of binary vectors and microbubbles was 1 ∶ 1,its efficiency of carrying SDF-1α gene and BMP-2 was approximately equal,and flow cytometry demonstrated that the positive rate of microbubbles labeled by both fluorescein isothiocyanate(FITC) and rhodamine was (65.6 ± 0.5)％.However,it was (59.0 ± 2.3)％ when their proportion was the 2 ∶ 1,which was significantly lower than those when other two proportions (1 ∶ 1 and 1 ∶ 2).Under the fluorescence microscope,the targeted microbubbles were equally surrounded by bright green or red fluorescence.Conclusions Ultrasound microbubbles of double genes carrying EGFP/SDF-1a and RFP/BMP2 is made successfully via biotin-streptavidin method.The optimal proportion of combining microbubbles with double gene is 1 ∶1,which can reveal the optimum load rate and stable combination.

The preventive effects of nitroglycerine (NG) on glucocorticoid-induced osteoporosis in growing rats were studied. Three-month-old female Wistar rats were randomly divided into control group (CON), dexamethasone group (DXM), DXM plus a low dose NG group (NG-L), DXM plus a middle dose NG group (NG-M) and DXM plus a high dose NG group (NG-H), 8 rats in each group. The rat model of osteoporosis was developed by intramuscular injection of dexamethasone twice a week. NG 0.2, 0.4 and 1.0 mg/kg was administered by oral gavages to the treatment groups every day for 12 weeks. Rats in CON group and DXM group were treated with normal saline of the same amount. After the treatment, the bone mineral density (BMD) and bone metabolism-associated biochemical markers were determined. Compared with CON group, BMD of lumbar spine and femur in DXM group was decreased significantly (P<0.05 and P<0.01 respectively), blood BGP levels and NO levels reduced (both P<0.01), and TRAP level increased (P<0.05). As compared with DXM group, BMD, serum BGP and NO were increased, and TRAP decreased in NG-L group and NG-M group, but had no significant difference in comparison to CON group. All the markers other than serum NO and TRAP levels had no significant difference between NG-H group and DXM group. It was concluded that low or middle doses of NG could prevent glucocorticoid-induced bone loss in growing rats, but high dose of NG could not. Supplement with NO donor could be considered as a preventive treatment for glucocorticoid-induced osteoporosis in a developing skeleton.
Bone Density/*drug effects ; Dexamethasone ; Nitric Oxide Donors/*therapeutic use ; Nitroglycerin/pharmacology ; Nitroglycerin/*therapeutic use ; Osteoporosis/chemically induced ; Osteoporosis/*prevention & control ; Random Allocation ; Rats, Wistar

The drugs promoting axon regeneration after spinal cord injury has been receiving high attention. Growth, extending and branching of neuron axon is a biological process mediated by cytoskeleton, and microtubule plays an important role on axon structure adjustment and growth. Taxol can reasonably stabilize microtubules, eliminate the obstacles of axon regeneration, and effect on axonal regeneration repair after spinal cord injury. Taxol is mainly used for anti-tumor therapy. This paper reviewed the researches on taxel and neuronal cytoskeletal microtubule.

The various advantages of organic polymer monoliths, including relatively simple preparation processes, abundant monomer availability, and a wide application range of pH, have attracted the attention of chromatographers. Organic polymer monoliths prepared by traditional methods only have macropores and mesopores, and micropores of less than 50 nm are not commonly available. These typical monoliths are suitable for the separation of biological macromolecules such as proteins and nucleic acids, but their ability to separate small molecular compounds is poor. In recent years, researchers have successfully modified polymer monoliths to achieve uniform compact pore structures. In particular, microporous materials with pores of 50 nm or less that can provide a large enough surface area are the key to the separation of small molecules. In this review, preparation methods of polymer monoliths for high-per-formance liquid chromatography, including ultra-high cross-linking technology, post-surface modifica-tion, and the addition of nanomaterials, are discussed. Modified monolithic columns have been used successfully to separate small molecules with obvious improvements in column efficiency.

Objective To investigate the characteristics of clinical course and outcome in elderly patients with nonvariceal upper gastrointestinal bleeding (NUGB) Methods The 206 hospitalized patients were devided into elderly group (≥60 yrs, 105 cases) and non elderly growp (