Research progress of Hedgehog signaling pathway regulating RANKL expression in osteoblasts / 中国组织工程研究

BACKGROUND: Hedgehog signaling pathway is shown to contribute to the osteogenesis of bone marrow mesenchymal stem cells, and to play an important role in regulating the expression of RANKL in osteoblasts. Nowadays, the definite signal transduction pathway has been revealed gradually.OBJECTIVE: To review the research progress of RANKL in osteoblasts that regulated by hedgehog signaling pathway.METHODS: A computer-based online search in CNKI, Google Scholar and PubMed databases was performed with the key words of Hedgehog, osteoblast, BMSCs, PTHrP, CREB, NFAT, RANKL in English and Chinese, respectively.Literatures related to the expression of RANKL in osteoblasts that regulated by the Hedgehog signaling pathway were included initially and 37 eligible articles were extensively summarized for review.RESULTS AND CONCLUSION: The Hedgehog signaling pathway plays an advanced role in the osteogenic differentiation of bone marrow mesenchymal stem cells, and also upregulates intracellular parathyroid hormone related protein, which activates its downstream signaling molecules cAMP response element binding protein and nuclear factor of activated T cells ulteriorly, to promote the expression of RANKL in osteoblasts and increase the differentiation and formation from osteoclast precursor cells to mature osteoclasts.

Latest research on zirconia implant surface treatment / 中国组织工程研究

BACKGROUND: Recently, zirconia ceramic implants have been reported to be used in clinic. Increasing studies on surface treatment of ziconia implants have been done, in order to promote bone-implant osseointegration and increase the success rate of implantation. There are no recognized surface treatment techniques of zirconia implants as yet.OBJECTIVE: To summarize the research progress in surface treatment techniques of zirconia implants.METHODS: The first author searched the CNKI, PubMed and Web of Science databases for relevant articles published from January 2000 to October 2016. The keywords were zirconia or zirconium, implant, surface treatment in Chinese and English, respectively. The search condition was((zirconia or zirconium) AND implant) AND surface treatment. Here,we reviewed the surface treatment techniques of zirconia implants, and introduced the properties, the surface treatment techniques and commercialization of zirconia implants.RESULTS AND CONCLUSION: Totally 23 papers were included in result analysis. Commonly used surface treatment technologies of zirconia implants include sand blasting, acid etching, sandblast and acid-etching, selective filtration etching, laser, ultraviolet and coating. These technologies all contribute to improving the surface activity of the implant,increasing the roughness, and promoting bone bonding to a certain extent.Because of the very limited experiments,further investigations are required to explore the optimum technique for the surface treatment of zirconia implants.

Preliminary application of injectable calcium phosphate cement/poly (lactic-co-glycolic acid) microspheres for extraction site preservation / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the feasibility of extraction site preservation using injectable calcium phosphate cement (CPC) combine with poly (lactic-co-glycolic acid) (PLGA) microspheres.</p><p><b>METHODS</b>Immediate extraction defects models were created in canine mandibles, and the defects were filled with CPC/PLGA (experimental group, E) , Bio-Oss (positive control, P), non-treatment (blank control, B) respectively. Dogs were sacrificed after 4, 8, 12 weeks post operation. Statistical analysis were conducted using SPSS 19.</p><p><b>RESULTS RESULTS</b>of radiological observation showed that there were not significantly different between groups in 4 and 8 week (P > 0.05). After 12 week,E (114.9 ± 8.4) were not significantly different compared with P (117.4 ± 12.1) (P > 0.05) , both were significantly higher than B (95.0 ± 12.6) (P < 0.05) . Histology examination showed that at 4 week following surgery, the result of newly formed bone was as follow, P[ (87.5 ± 1.5) %] > B[(78.7 ± 2.7)%] > E[(69.2 ± 1.8)%] (P < 0.05). At 8, 12 week, results of P[(94.0 ± 2.3)% and (93.5 ± 1.9) %] and E[ (94.7 ± 1.1) % and (96.0 ± 0.9) %] were better than those of B[ (76.8 ± 3.0)% and (87.0 ± 2.4)%] (P < 0.05).</p><p><b>CONCLUSIONS</b>The effect of CPC/PLGA repair immediate alveolar ridge defects is the same as that of Bio-Oss, and CPC/PLGA can be used as a material in extraction site preservation.</p>

Prevalence and risk factors of human papillomavirus infectious in HIV-positive women / 中华临床感染病杂志

Objective To evaluate the prevalence and risk factors of human papillomaviruses (HPV)infection among human immunodeficiency virus(HIV)-positive women.Methods Totally 178HIV-positive and 122 HIV-negative women were enrolled.Structured interviews,peripheral CD4 + T cells counts and cervical specimens were obtained.Polymerase chain reaction(PCR)assay was used to identify HPV types. SPSS 16.0 was used for statistical analysis,and logistic regression was used to identify independent prognostic factors for high-risk HPV infection. Results HPV positive rate,high-risk and multiple HPV infection rates were 38.2% vs.12.3% ,35.4% vs.8.2% ,and 13.5% vs.3.3% in HIVpositive women and HIV-negative women,respectively,and the differences were of statistical significance (x2 =24.77,29.08 and 8.91,P ＜0.05).The common types of high-risk HPV were similar between HIV-positive and HIV-negative women(HPV16,52,58 and 18).CD4 + T count ＜ 350/pL,HIV-positive in husband,and HIV infection through sexual contact were risk factors for high-risk HPV infection in HIV-positive women.Conclusion sThe prevalence of HPV infection in HIV-infected women is high,especially for high-risk HPV infection and multiple infection.High-risk HPV infection usually occurs in HIV-positive women with low immune status,HIV infection through sexual contact and HIV-positive husband.

Study on bonding strength of TF adhesive compounded with nanograde hydroxyapatite / 生物医学工程学杂志

TF no-mix orthodontic adhesive was compounded in different weight proportion of nanograde hydroxyapatite as 10%, 20% and 30%, for use in this comparative study on composites. 80 orthodontic brackets were cemented and divided into 8 experimental groups, and TF adhesive was set as the control group. The tensile strength and shear strength were tested respectively. The results showed that the group of 10% nanograde hydroxyapatite obtained the greatest bonding strength (9.668 +/- 1.0649 MPa in tensile strength and 11.991 +/- 1.4135 MPa in shear strength), and there was significant difference between the 10% group and the other groups (P < 0.05, one-way ANAOV). It is concluded that the bonding strength can be enhanced when TF adhesive is compounded in suitable proportion of nanograde hydroxyapatitie.