Bioactive glass 45S5-silk fibroin membrane supports proliferation and differentiation of human dental pulp stem cells / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the effect of bioactivity glass 45S5- silk fibroin(BG45S5- SF) membrane on growth, proliferation and differentiation of human dental pulp stem cells(hDPSC), and to provide new ideas and method for the regeneration of pulp-dentine complex.</p><p><b>METHODS</b>hDPSC seed on pure silk fibroin membrane (protein membrane group) and BG45S5-SF membrane with different concentrations(1 000, 5 000 mg/L, composite membrane group A and B, respectively) were prepared, and the materials were incubated in cell culture fluid for 24 h. No material membrane orifice plate was used as blank control group. Contact angle meter was used to measure surface contact angle of protein membrane and composite membrane group(each group had three repeated holes). Cell proliferation was assessed by cell counting kit- 8 on the 4, 7, 14, and 21 days. The state of adhesion and growth of hDPSC on the materials surface was evaluated by scanning electron microscopy and cytoskeleton staining; and alkaline phosphatase (ALP) activity was measured to evaluate the cell differentiation potential. The expression of odontoblastic differentiation-related genes was measured by real-time PCR.</p><p><b>RESULTS</b>Surface contact angle of the protein membrane group and composite membrane group A and group B were 89.51° ± 0.12°, 70.32° ± 0.07° and 71.31° ± 0.09° respectively. hDPSC adhered well on each materials surface on the 7, 14, 21 days, ALP activity and differentiation genes of composite membrane group A and B rised more significantly than the blank control group and protein membrane group did (P<0.05). Dentin matrix protein1(DMP- 1), dentin sialoprotein(DSP), ALP, osteocalcin(OC) mRNA expression reached peak on the 14 days in group A, and in group B on the 21 days. Bone sialoprotein(BSP) mRNA expression in both group A and B reached peak on the 21 days.</p><p><b>CONCLUSIONS</b>BG45S5- SF membrane is able to support the proliferation and showed the potential of odontoblastic differentiation for hDPSC. This finding suggests that BG45S5-SF membrane was a kind of tissue engineering film material with the regeneration potential for pulp-dentine complex.</p>

Regulatory effects of hedgehog pathway on intestinal epithelial barrier function under hypoxia / 中华消化外科杂志

Objective To investigate the regulatory effects of hedgehog pathway on intestinal epithelial barrier function under hypoxia.Methods The IEC-6 cells of rats were divided into 3 groups:the normoxia group (21％ oxygen concentration),the hypoxia group (2％ oxygen concentration) and the hypoxia + cyclopamine group (cells pretreated by 5 mmol/L of cyclopamine,and then exposed in an atmosphere with 2％ oxygen concentration).The mRNA expressions of IHH,PTCH and GLI-1 were detected,and the transepithelial electrical resistance (TER) was determined.The protein expressions of tight junction proteins (ZO-1,Occludin,Claudin-1) and IHH were assayed by using the Western blot.All data were analyzed using the one-way analysis of variance or LSD-t test.Results The relative mRNA expressions of IHH,PTCH and GLI-1 were 0.056 ± 0.009,0.459 ± 0.087,0.142 ± 0.023 in the normoxia group,and 0.303 ± 0.052,0.678 ± 0.073,0.483 ± 0.061 in the hypoxia group,with significant difference between the 2 groups (t =-14.05,-11.85,-6.52,P ＜ 0.05).The relative protein expressions of IHH in the normoxia group and the hypoxia group were 0.39 ±0.06 and 0.91 ±0.15,with a significant difference between the 2 groups (t =-8.08,P ＜ 0.05).The TERs of the normoxia group,the hypoxia group and the hypoxia + cyclopamine group were (134 ± 5) Ohm/cm3,(100 ± 6) Ohm/cm3 and (118 ± 5) Ohm/cm3,with significant difference between the 3 groups (F =1.04,P ＜ 0.05).Compared with the normoxia group,the TER of the hypoxia group was decreased by 27.7％ (t =7.84,P ＜ 0.05) ; compared with the hypoxia group,the TER of the hypoxia + cyclopamine group were increased by 16.4％,but it was still significantly lower than the normoxia group (t =4.23,P ＜ 0.05).The expressions of ZO-1,Occludin and Claudin-1 were 1.18 ± 0.24,0.80 ±0.13 and 0.90 ±0.09 in the normoxia group,and 0.58 ±0.08,0.32 ±0.05 and 0.50 ±0.09 in the hypoxia group,and 0.92 ± 0.21,0.43 ± 0.10 and 0.82 ± 0.11 in the hypoxia + cyclopamine group,with significant difference between the 3 groups (F =4.95,2.88,10.09,P ＜0.05).The expressions of ZO-1,Occludin and Claudin-1 in hypoxia group were decreased by 48.7％,40.0％ and 55.6％ when compared with the normoxia group (t =12.86,9.35,18.90,P ＜0.05).The expressions of ZO-1,Occludin and Claudin-1 in the hypoxia + cyclopamine group were increased by 59.9％,35.2％ and 65.1％ when compared with the hypoxia group (t =5.63,2.92,6.66,P ＜ 0.05).Conclusion Hedgehog signal pathway could be activated under hypoxia,and then the expressions of tight junction proteins are decreased,which finally induces the injury of intestinal epithelial barrier function.

Anatomic study and clinical application of double- branched thoracodorsal nerve / 中华骨科杂志

Objective To study the lateral branch of thoracodorsal nerve and the deltoid branch of axillary nerve under microscope for clinical application in the reconstruction of brachial nerve injury. Methods 31 lateral branches and deltoid branches of axillary nerve on 17 cadaver specimens were studied on topography under the light microscope(? 5) to observe the length, diameter, and the number of branches. The number of fibers was counted on the HE- stained section of the nerves. Three cases were performed: In operationⅠ , the lateral branch of thoracodorsal nerve was connected with the deltoid branch of axillary nerve. In operationⅡ , on the base of the first operation, the medial branches of the thoracodorsal nerve partially the latissimus dorsi was reconstructed for recovery of the flexion function of the elbow. In operationⅢ , the latissimus dorsi was section into two parts according to the innervation of the medial and lateral branches of the thoracodorsal, and the two branches of the thoracodorsal were transplanted in a dislplaced position for the restoration of flexion function of the elbow and the fingers. Results Thoracodorsal nerves have 2 branches near dorsal aspect of the latissimus dorsi. The lateral branch is thicker with the average length of 58.2 mm avaliable for the reconstruction purpose; the diameter is in average of 1.46 mm, the number of fibers is in average of 1 519; 90.4％ of the lateral branches redivided into 2 or 3 branches. The diameter of the deltoid branch of axillary nerve is 2.31 mm in average and 61.3％ give 3 branches; 32.3％ 2 branches; the number of fibers is in average of 2 341. Clinically the reconstruction operation is successful. In operationⅠ the strength of the deltoid muscle recovered to grade 4; in operationⅡ the strength of the deltoid muscle and elbow- flexing is reached grade 4 and in operationⅢ the strength of elbow- and finger- flexion recovered to grade 4. Conclusion Reconstruction of two muscular groups of the latissimus dorsi with loss of nerve innervation is effective by the application of double branch potential of the thoracodorsal nerve.