Objective: The purpose of this study was to investigate the effect of TNF-? on osteoclast differentiation in primary murine bone marrow cell culture with and without RANKL. Methods: M-CSF-dependent bone marrow cells were isolated from 5-6 weeks old mice, and cultured in the presence of M-CSF (25 ?g/L) with different concentrations of TNF-? (0, 1, 10, 100 ?g/L) for 5 days, the formation of TRAP(+) multinucleated cells was observed. These cells were also cultured in the presence of both RANKL (30 ?g/L) and M-CSF (25 ?g/L) with or without 10 ?g/L TNF-? for 4, 5, 6 and 9 days. The number of TRAP(+) multinucleated cells and resorption pits on dentine slices were counted under light microscope. Results: In the absence of RANKL, TNF-? was unable to induce osteoclast formation from murine bone marrow precursors. In the presence of RANKL, TNF-? augmented osteoclastogenesis and bone resorption, and this effect occurred only on the early stage. Conclusion: TNF-? enhances RANKL-induced osteoclast formation and function, but can’t substitute for RANKL. TNF-? stimulates osteoclast differentiation, but not survival.

Obesity is caused by the imbalance between caloric intake and energy expenditure. It is also influenced by genetic factors. Many genes,such as ob gene, ? 3 receptor gene, ucp 1 gene, may involved in the prevalence of obesity. Pharmacologic treatments include anorexigenic agents, lipase inhibitor, ? 3 receptor agonists and many newer antiobesity drugs, which provide prospective ways in treating obesity.

A new method based on convolution kernel compensation (CKC) for decomposing multi-channel surface electromyogram (sEMG) signals is proposed in this paper. Unsupervised learning and clustering function of self-organizing map (SOM) neural network are employed in this method. An initial innervations pulse train (IPT) is firstly estimated, some time instants corresponding to the highest peaks from the initial IPT are clustered by SOM neural network. Then the final IPT can be obtained from the observations corresponding to these time instants. In this paper, the proposed method was tested on the simulated signal, the influence of signal to noise ratio (SNR), the number of groups clustered by SOM and the number of highest peaks selected from the initial pulse train on the number of reconstructed sources and the pulse accuracy were studied, and the results show that the proposed approach is effective in decomposing multi-channel sEMG signals.
Algorithms ; Cluster Analysis ; Electromyography ; Neural Networks (Computer)

Objective: To explore suitable concentration of recombinant human transforming growth factor β1 (rhTGF-β1) usage and study the effect of rhTGF-β1 on differentiation of dental pulp stem cells (DPSCs).Methods: DPSCs were isolated from the undiseased third molars of people aged 18-25 years and cultured according to instructions in vitro.Different concentrations (1 , 6 , 10 μg/L) of rhTGF-β1 were added to the culture medium to examine DPSCs proliferation by CCK-8 (cell counting kit-8) assay.The suitable concentration was then selected.For differentiation, the DPSCs were incubated for 7 or 14 days with rhTGF-β1 supplemented with osteo/odontoblastic induction medium containing 10 nmol/L dexamethasone, 10 mmol/L b-glycerophosphate, 50 g/L ascorbate phosphate, 10 nmol/L 1,25-dihydroxyvitamin D3 and 10% fetal bovine serum.The cells were then washed 3 times with phosphate-buffered saline and sonicated with 1%Triton X-100 for 30 minutes on ice.Cellular alkaline phosphatase (ALP) activity was assayed with p-nitrophenyl phosphate as the substrate.The enzyme activity was expressed as p-nitrophenyl produced per milligram of protein [bicinchoninic acid (BCA) protein assay kit].To examine mineral nodule formation, the cultured cells were fixed in 4% paraformaldehyde and washed in water, and the mineralization of the extracellular matrix was assayed by 1% alizarin red S staining and elution of staining was examined as optical density (D) under microplate reader.The mean difference was considered significant at 0.05 and 95% confidence interval.Results: The DPSCs had ty-pical fibroblast morphology and could form mineral nodules after being cultured with osteo/odontoblstic induction medium for 14 days.6 μg/L rhTGF-β1 significantly promoted the DPSCs proliferation on the 3rd and 5th days.After the incubation of osteo/odontoblastic induction medium, the DPSCs with the 6 μg/L rhTGF-β1 increased ALP activities compared with the control;D values in the 6 μg/L rhTGF-β1 group was 0.31±0.03, while the control group was 0.02±0.01(P<0.05).The total protein content in the 6 μg/L rhTGF-β1 group was (2 775.46±83.54) mg/L, and the control group was (1 432.20±110.83) mg/L (P<0.05).To eliminate the cells proliferation influence, relative ALP activities, which was defined as the total ALP divided by the total protein content, the 6μg/L rhTGF-β1 group was 6 times higher than the control group.Alizarin red S staining showed increased mineral nodule formation in the rhTGF-β1 group.The elution of staining under microplate reader also showed more optical density in the 6 μg/L rhTGF-β1-treated cells (0.83±0.02) than that in the control groups (0.55±0.05, P<0.05).Conclusion: 6 μg/L rhTGF-β1 could significantly promote DPSCs proliferation and odontoblastic differentiation in vitro.

Objective:To compare the proliferation and osteoblastic differentiation of dental pulp stem cell (DPSC)isolated from normal and inflamed pulps of different degrees in Beagle immature premolars, and provide evidence for the use of inflammatory DPSC (IDPSC).Methods:This study evaluated 14 Beagle’s young premolars (21 roots).In the experiment group,irreversible pulpitis was induced by pulp exposure and the inflamed pulps were extracted 2 weeks and 6 weeks after the pulp chamber opening.For the control group,normal pulps were extracted immediately after the exposure.HE staining and real-time PCR were performed to confirm the inflammation.The cells were isolated from the inflamed and normal pulps (IDPSC and DPSC).Cell proliferation and osteoblastic differentiation potentials of the two cells were compared.Results:Inflammation cells infiltration was observed in the inflamed pulps by HE stai-ning.The expression of inflammatory factor was much higher in the 6 week inflamed pulp.IDPSC had higher potential of cell proliferation and osteoblastic differentiation potentials.Furthermore,the osteoblas-tic differentiation potentials of IDPSC from 2 week inflamed pulp were higher than those from 6 week in-flamed pulp.Conclusion:The potential of cell proliferation and osteoblastic differentiation of DPSC was enhanced at early stage of irreversible pulpitis,and reduced at late stage in Beagle immature premolars.

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 investigate the effect of TGF-? on osteoclast differentiation in primary murine bone marrow cell culture in the presence of receptor activator of NF-?B Ligand(RANKL) and macrophage colony stimulating facotr(M-CSF).Methods:M-CSF-dependent bone marrow cells were isolated from 5~6 weeks old mice,and cultured in the presence of RANKL at 30 ng/ml and M-CSF at 25 ng/ml with or without 1 ng/ml of TGF-? for 4 and 9 days respectively.TRAP positive multinucleated cells and resorption pits on dentine slices were counted under light microscope.Results:TRAP positive multinucleated cells were induced from murine bone marrow cell cultures with both RANKL and M-CSF,and these cells formed resorption pits on dentine slices.The number of TRAP positive multinucleated cells and resorption pits were significantly increased by 1 ng/ml of TGF-?(P

Indoor microbial contamination of the buildings and the related health impacts has been more and more concerned by the public.The indoor microbial contaminants contain bacteria,virus,fungus,dust mites,pollen and so on,and the source is diversity.Many studies at home and abroad have found that the microbial contaminants in different kinds of the buildings like the public places,schools,living rooms and so on are very popular,sometimes quite high level.Indoor microbial contamination can cause adverse impact on health of the exposed population,such as some infectious diseases,allergenic symptoms/diseases,even cancers.

Objective To know the microbial pollution in the indoor air of classrooms and dormitories in a university and analyze the possible impact factors.Methods In April and May,2007,the indoor air sampling was conducted and the total count of air microbe in indoors was determined in eight classrooms and twenty dormitories by the impacting method.Results According to the related national hygienic standard of China, the total count of air microbe in all classrooms was qualified, the total count of air microbe in the dormitories was all qualified, but it was higher in male's dormitories compared with female's.Conclusion In general, there was not obviously indoor microbial pollution in the investigated university.

0.05) . Conclusion Air pollution can increase the risk of low birth weight and preterm birth in the exposed pregnant women.