BACKGROUND: Mesenchymal stem cells (MSCs) can differentiate into osteoblasts in the action of dexamethasone; Meanwhile, bone morphogenetic protein-2 (BMP-2) can promote the cell proliferation and differentiation, and matrix secretion in the process of bone repair. BMP-2 plays an important role in treating fracture and bone defects by inducing bone formation both in vivo and in vitro.OBJECTIVE: To analyze whether dexamethasone induction in vitro could enhance the ability of BMP-2 modified MSCs in osteogenic conversion.DESIGN: A randomized paired design.SETTING: Xijing Hospital of the Fourth Military Medical University of Chinese PLA.MATERIALS: The experiments were carried out in the Orthopaedic Oncology Institute of Chinese PLA, the Fourth Military Medical University of Chinese PLA from February to August in 2004. Twenty 20-month-old New Zealand rabbits were provided by the experimental animal center of the Fourth Military Medical University of Chinese PLA [Certificate number: 2005C00117]. The rabbits were raised normally at room temperature with normal humidity. The samples were collected bilaterally, the cells from the left limb were taken as the dexamethasone-induced group, and those from the right limb as the control group.METHODS: MSCs treated and untreated with dexamethasone were transfected with BMP-2 gene, then the BMP-2 expression was determined by reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemical staining. The growths of the MSCs were observed, and the activity of alkaline phosphatase (ALP) and osteocalcin of MSCs were determined with ALP kit and osteocalcin radioimmunoassay kit after Ad-BMP-2 transfection.MAIN OUTCOME MEASURES: ① BMP-2 expression in MSCs; ② Morphological changes of the MSCs; ③ ALP activity and osteocalcin content in the MSCs. RESULTS: ① Expressions of BMP-2 gene could be observed in MSCs both treated and untreated with dexamethasone after transfection. ② The forms were irregular in most of the MSCs treated with dexamethasone, appeared as triangular or polygonal changes.They grew more slowly than those cultured with basic medium. There were no obvious changes of cellular forms after gene transfection. ③ Five days after transgene, the ALP activity in the MSCs supernatant in the dexamethasone-induced group was higher than that in the control group [(134.36±8.84), (104.02±7.83) nkat/L, t =3.350 6, P ＜ 0.01, n =20]. The amount of osteocalcin secretion in MSCs in the dexamethasone-induced group was higher than that in the control group [(14.68±0.73), (6.52±1.21) μg/L, t =3.568 2, P ＜ 0.01, n =20].CONCLUSION: Dexamethasone induction before transgene can promote the proliferation of BMP-2 modified MSCs and the conversion into osteoblasts.

Adolescent ; Child ; Electromyography ; Female ; Humans ; Male ; Stomach ; physiology

Objective To investigate and compare the killing effects of different prodrugs combined with suicide gene HSV-tk on laryngocacinoma cell, Hep-2 in vitro. Methods Retroviral expressing vector pL(tk)SN was constructed by recombinant DNA technology. Hep-2 cells were infected by the recombinant retrovirus. The positive cloning was obtained after G418 selection and were termed Hep/tk. The integration and expression of tk gene in Hep-2 cells were identified by RT-PCR and Southern blot. The growth state and prodrugs killing effect of tk gene modified cells were used to investigate the expression of tk gene and antitumour effect on Hep-2 cells. Results RT-PCR and Southern blot analysis confirmed the integration and expression of tk gene in Hep-2 cells. There was no significant difference in cell proliferation between the Hep/tk and Hep-2. After the treatment of GCV,the Hep/tk showed high sensitivity to GCV and bystander effects were observed siginificantly in vitro. However the efficiency of another two prodrugs ACV and BVdU was lower than that of GCV. Both tk-positive and tk-negative Hep-2 cells were relatively insensitive to ACV and BVdU.Treatment of tk gene modified cells mixed with different proportion parental cells shoewd obviously bystander effects.Conclusions The laryngocarcinoma cells Hep-2 have sensitive to HSV-tk/GCV system and have significant bystander effects, which might have therapeutic potential value for laryngocarcinoma.

Humans ; Salivary Glands

Humans ; Osteogenesis, Distraction ; instrumentation

Immobilization is a usual method to treat the injury of skeletal muscle system and plays an important role in rehabilitation of diseases. But immobilization also displays some negative effects, of all, muscle system is affected significantly. The mechanism is explored in the article from immobilization-induced skeletal muscle atrophy, the dropping of muscle power, reduction of vessels density in muscle and metabolic disturbance of muscle. The authors of the article advances that shortening the period of immobilization as possible and performing early rehabilitation are important to remove the negative influence of immobilization, but all treatments should obey the medical rules.

AIM: To investigate the relationship between levels of blood viscosity and ocular hemodynamic changes in patients of primary glaucoma (PG).METHODS: The blood rheology indices (including whole blood, plasma, packed cell, relative blood visco-sities and yield stress) were determined in primary open angle glaucoma (POAG) patients, primary acute angle closure glaucoma (PAACG) patients, primary chronic angle closure glaucoma (PCACG) patients and normal control group (patients with senile cataract), 20 cases each group. The peak systolic velocity (PSV), end diastolic velocity (EDV), resistant index (RI), shape of spectra and frequency of monitor of ophthalmic artery (OA) and central artery of retina (CRA) were detected with color Doppler imaging (CDI) simultaneously. Comparing to the differences of each group with t test and giving a linear relational analysis to targets between the blood viscosity and hemodynamic of primary glaucoma patients.RESULTS: The blood rheology targets in PG groups were significantly higher than those in control group except fibrinogen. Comparing to control group, PSV and EDV in PG groups were significantly decreased but RI was remarkably increased. All targets of blood viscosity in PG patients were significantly negatively correlated with the PSV, EDV of both OA and CRA, but were significantly positively correlated with RI of OA and CRA. There were no significant correlations between the blood viscosity and ocular hemodynamics in the normal control.CONCLUSION: There are ocular blood circulation obstacles in and high level of blood viscosity PG patients, CDI has an important reference value in early diagnosis and prognosis of glaucoma.

OBJECTIVE: To establish miniSTR fluorescent detection system with all detected fragments below 150 bp and to enhance the efficiency of detecting the degraded DNA samples. METHODS: All candidate primers were designed by Primer Premier 5 and screened by FastPCR 6.0. The miniSTR multiplex system was established by these selected loci labeling by four fluorescent dye. The parameters of PCR and primer concentrations were subsequently optimized. The electrophoresis was fulfilled under POP4 on 3100-Avant and the typing data was validated by standard DNA 9947A and 007. Fresh blood samples and difficult degraded DNA samples were tested to evaluate the usefulness of the system. RESULTS: All amplicons in the established miniSTR fluorescent detection system (D12ATA63, D2S1776, D1GATA113, D4S2408, D17S974, D20S482, D3S3053, Amelogenin, D6S474, D9S1122) were less than 150bp. The profile showed a balanced peak height without extra stutter by optimal protocol. Allele frequencies showed no deviations from Hardy-Weinberg equilibrium. The system showed accumulated probability of discrimination 0.999 999 983 and accumulated triplet excluding probability of paternity 0.996 8. It could detect corrupt muscle tissue, low copy number DNA samples and human tissues fixed by 40% formaldehyde solution for 12 days. CONCLUSION The miniSTR fluorescent detection system could be solely used for personal identification of degraded DNA samples or complementally used for paternity tests. And the system could enhance the ability of detecting the trace and degraded DNA.
DNA/chemistry* ; DNA Fingerprinting ; DNA Primers/genetics* ; Electrophoresis, Agar Gel ; Forensic Genetics ; Gene Frequency/genetics* ; Genetic Markers/genetics* ; Genetics, Population ; Humans ; Polymerase Chain Reaction/methods* ; Reference Standards ; Sequence Analysis, DNA/methods*

Objective To establish the model of amyotrophic lateral sclerosis (ALS) with selective motor neuron disorder by organotypic spinal cord cultures, and analyze the role of astrocyte in the pathagenisis of ALS.Methods Organotypic spinal cord cultures were prepared using lumbar spinal cord slices from 8-day-old SD rat pups. The threohydroxyaspartate (THA) was applied into culture medium to establish ALS organotypic spinal cord cultures model. Motor neurons survival was evaluated by monoclonal SMI-32 immunohistochemical staining and glial fibrillary acidic protein staining to show astrocyte survival.Results Compared with the control group, there was significantly astrogliosis in the anterior horn and surrounding white matter in THA 100 μmol/L group, and the level of gliosis was increased followed the elongation of THA interference time. With the increasing of the number of astrocyte, the morphology of astrocyte was changed.Conclusion There is significantly astrogliosis in the anterior horn and the time of astrogliosis is markedly earlier than the time of motor neuron loss in the ALS model intervented with THA.

Objective To evaluate the cancer risk of benzene and formaldehyde in different indoor air environments in Guiyang city.Methods From 2004 to 2005,benzene and formaldehyde monitoring was conducted in bedrooms,living rooms, kitchens,offices,classrooms and outdoor environments in winter,spring and autumn,and human health risk assessment was done. Results The mean benzene and formaldehyde concentration in different environments were lower than the China indoor air quality standard except for formaldehyde concentration in offices.The benzene cancer risks of male and female adults were 1.63?10~4 and 1.40?10~(-4)respectively.The formaldehyde cancer risks of male and female adults were 6.05?10~(-4)and 5.23?10~(-4) respectively.The human formaldehyde cancer risk was higher than benzene cancer risk,and the risk for male was higher than that for female.Benzene and formaldehyde cancer risks of different population in different indoor environments were above 1.00?10~(-6), the acceptable level of human cancer risk.Conclusion The benzene and formaldehyde concentrations in different environment in Guiyang city has the high cancer risks to human health.