AIM: To investigate the effect of stem cells from human exfoliated deciduous teeth(SHED) transplanted for bone regeneration in the dog mandibular defect.METHODS: In this prospective comparative study, SHEDs had been i...AIM: To investigate the effect of stem cells from human exfoliated deciduous teeth(SHED) transplanted for bone regeneration in the dog mandibular defect.METHODS: In this prospective comparative study, SHEDs had been isolated 5 years ago from human exfoliated deciduous teeth. The undifferentiated stem cells were seeded into mandibular bone through-andthrough defects of 4 dogs. Similar defects in control group were filled with cell-free collagen scaffold. After 12 wk, biopsies were taken and morphometric analysis was performed. The percentage of new bone formation and foreign body reaction were measured in each case. The data were subject to statistical analysis using the Mann-Whitney U and Kruskalwalis statistical tests. Differences at P < 0.05 was considered as significant level.RESULTS: There were no significant differences between control and SHED-seeded groups in connective tissue(P = 0.248), woven bone(P = 0.248) and compact bone(P = 0.082). There were not any side effects in transplanted SHED group such as teratoma or malignancy and abnormalities in this period.CONCLUSION: SHEDs which had been isolated and characterized 5 years ago and stored with cryopreservation banking were capable of proliferation and osteogenesis after 5 years, and no immune response was observed after three months of seeded SHEDs.展开更多
BACKGROUND Autoimmune hepatitis is a serious autoimmune liver disease that threatens human health worldwide,which emphasizes the urgent need to identify novel treatments.Stem cells from human exfoliated deciduous teet...BACKGROUND Autoimmune hepatitis is a serious autoimmune liver disease that threatens human health worldwide,which emphasizes the urgent need to identify novel treatments.Stem cells from human exfoliated deciduous teeth(SHED),which are easy to obtain in a non-invasive manner,show pronounced proliferative and immunomodulatory capacities.AIM To investigate the protective effects of SHED on concanavalin A(ConA)-induced hepatitis in mice,and to elucidate the associated regulatory mechanisms.METHODS We used a ConA-induced acute hepatitis mouse model and an in vitro co-culture system to study the protective effects of SHED on ConA-induced autoimmune hepatitis,as well as the associated underlying mechanisms.RESULTS SHED infusion could prevent aberrant histopathological liver architecture caused by ConA-induced infiltration of CD3+,CD4+,tumor necrosis-alpha+,and interferon-gamma+inflammatory cells.Alanine aminotransferase and aspartate aminotransferase were significantly elevated in hepatitis mice.SHED infusion could therefore block ConA-induced alanine aminotransferase and aspartate aminotransferase elevations.Mechanistically,ConA upregulated tumor necrosisalpha and interferon-gamma expression,which was activated by the nuclear factor-kappa B pathway to induce hepatocyte apoptosis,resulting in acute liver injury.SHED administration protected hepatocytes from ConA-induced apoptosis.CONCLUSION SHED alleviates ConA-induced acute liver injury via inhibition of hepatocyte apoptosis mediated by the nuclear factor-kappa B pathway.Our findings could provide a potential treatment strategy for hepatitis.展开更多
Reference values reflecting the findings of natural concentrations of teeth in a well-defined group of individuals, are indispensable, if one is to interpret results generated for clinical utility. Hence, a comprehens...Reference values reflecting the findings of natural concentrations of teeth in a well-defined group of individuals, are indispensable, if one is to interpret results generated for clinical utility. Hence, a comprehensive compilation of literature survey is attempted to make available as a reference guideline for tooth element concentrations. Presently, the reference values are proposed for 19 elements. Several factors that are found influencing element levels, are common to any biosample and are broadly grouped under four categories namely, the factors of teeth, donor, environment and analytical methods. How best the influencing factors to be considered during analysis, are discussed. It is elucidated that standardized method of analysis with quality assurance and precision will reduce the ambiguity of comparison of inter-laboratory measurement. When the merits and demerits of element measurements are evaluated, it is recognized that except a hurdle of difficult specific sampling, many advantages make teeth an attractive material for environmental health monitoring of population and for assessment of element status of deficiency and excess due to differential exposure. The available data of tooth elements are lesser in comparison to data of blood and hair;further studies are required for reference values of others elements and for distribution pattern in different conditions, parts and types of teeth.展开更多
目的初步探索不同浓度骨碎补总黄酮(total flavone of rhizoma drynariae)对乳牙牙髓干细胞(stem cells from human exfoliated deciduous teeth)增殖及成骨分化能力的影响。方法2020年3月—2021年8月黑龙江省医院检验科初步筛选出适宜...目的初步探索不同浓度骨碎补总黄酮(total flavone of rhizoma drynariae)对乳牙牙髓干细胞(stem cells from human exfoliated deciduous teeth)增殖及成骨分化能力的影响。方法2020年3月—2021年8月黑龙江省医院检验科初步筛选出适宜浓度的RDTF,三代分离、培养SHEDs,通过流式细胞术及茜素红染色分别对细胞表面标志物和成骨分化潜能进行鉴定。实验分为4组(0时段为对照组,24、48、72 h组),每组设置3个复孔,采用不同浓度RDTF处理SHEDs后钙钴法染色,Western blot法检测其成骨相关蛋白表达情况。结果结果显示,所获取的细胞为具有成骨分化能力的SHEDs。与对照组相比,24、48、72 h内各浓度组均对SHEDs增殖无明显影响,差异无统计学意义(P>0.05),12.5、25 mg/L RDTF组的Runt相关转录因子2(Runx2)及骨钙素(OCN)的蛋白表达均显著上调,其中25 mg/L RDTF组对Runx2表达的促进效果最明显(249.681±14.653),差异有统计学意义(F=102.7,P<0.001)。结论RDTF对SHEDs的增殖无显著影响,可促进SHEDs成骨分化。展开更多
目的:利用RNA测序(RNA sequencing,RNA-seq)技术研究人脱落乳牙干细胞(stem cells derived from human exfoliated deciduous teeth,SHED)体外长时期扩增至20代(P20)后基因表达的差异,初步探讨其体外扩增衰老相关的信号通路。方法:从健...目的:利用RNA测序(RNA sequencing,RNA-seq)技术研究人脱落乳牙干细胞(stem cells derived from human exfoliated deciduous teeth,SHED)体外长时期扩增至20代(P20)后基因表达的差异,初步探讨其体外扩增衰老相关的信号通路。方法:从健康儿童脱落的乳牙中分离牙髓干细胞,在常规条件下将其扩增培养至20代,利用RNA-seq筛选出差异表达的基因,并对其进行相关生物学信息分析,寻找SHED体外连续扩增衰老相关的信号通路。结果:RNA-seq结果显示,SHED第4代(P4)和P20代差异表达的基因共有1884个,其中上调表达的基因有575个,下调表达基因1309个,这些差异表达的基因分布在生物过程(biological progress,BP)、细胞组成(cellular component,CC)和分子功能(molecular function,MF)等生物学过程中。早、晚期代次的SHED差异基因及相关蛋白之间的作用主要富集在剪接体、核糖体、细胞周期、p53通路相关的信号通路上。结论:本研究揭示了SHED体外连续扩增培养至第20代后基因表达谱的改变,为后续进一步研究其细胞体外衰老机制指明了方向。展开更多
文摘AIM: To investigate the effect of stem cells from human exfoliated deciduous teeth(SHED) transplanted for bone regeneration in the dog mandibular defect.METHODS: In this prospective comparative study, SHEDs had been isolated 5 years ago from human exfoliated deciduous teeth. The undifferentiated stem cells were seeded into mandibular bone through-andthrough defects of 4 dogs. Similar defects in control group were filled with cell-free collagen scaffold. After 12 wk, biopsies were taken and morphometric analysis was performed. The percentage of new bone formation and foreign body reaction were measured in each case. The data were subject to statistical analysis using the Mann-Whitney U and Kruskalwalis statistical tests. Differences at P < 0.05 was considered as significant level.RESULTS: There were no significant differences between control and SHED-seeded groups in connective tissue(P = 0.248), woven bone(P = 0.248) and compact bone(P = 0.082). There were not any side effects in transplanted SHED group such as teratoma or malignancy and abnormalities in this period.CONCLUSION: SHEDs which had been isolated and characterized 5 years ago and stored with cryopreservation banking were capable of proliferation and osteogenesis after 5 years, and no immune response was observed after three months of seeded SHEDs.
基金Supported by The National Natural Science Foundation of China,No.81970940 and No.81600865Beijing Natural Science Foundation,No.7182182and the National Science and Technology Major Project of the Ministry of Science and Technology of China,No.2018ZX10302207.
文摘BACKGROUND Autoimmune hepatitis is a serious autoimmune liver disease that threatens human health worldwide,which emphasizes the urgent need to identify novel treatments.Stem cells from human exfoliated deciduous teeth(SHED),which are easy to obtain in a non-invasive manner,show pronounced proliferative and immunomodulatory capacities.AIM To investigate the protective effects of SHED on concanavalin A(ConA)-induced hepatitis in mice,and to elucidate the associated regulatory mechanisms.METHODS We used a ConA-induced acute hepatitis mouse model and an in vitro co-culture system to study the protective effects of SHED on ConA-induced autoimmune hepatitis,as well as the associated underlying mechanisms.RESULTS SHED infusion could prevent aberrant histopathological liver architecture caused by ConA-induced infiltration of CD3+,CD4+,tumor necrosis-alpha+,and interferon-gamma+inflammatory cells.Alanine aminotransferase and aspartate aminotransferase were significantly elevated in hepatitis mice.SHED infusion could therefore block ConA-induced alanine aminotransferase and aspartate aminotransferase elevations.Mechanistically,ConA upregulated tumor necrosisalpha and interferon-gamma expression,which was activated by the nuclear factor-kappa B pathway to induce hepatocyte apoptosis,resulting in acute liver injury.SHED administration protected hepatocytes from ConA-induced apoptosis.CONCLUSION SHED alleviates ConA-induced acute liver injury via inhibition of hepatocyte apoptosis mediated by the nuclear factor-kappa B pathway.Our findings could provide a potential treatment strategy for hepatitis.
文摘Reference values reflecting the findings of natural concentrations of teeth in a well-defined group of individuals, are indispensable, if one is to interpret results generated for clinical utility. Hence, a comprehensive compilation of literature survey is attempted to make available as a reference guideline for tooth element concentrations. Presently, the reference values are proposed for 19 elements. Several factors that are found influencing element levels, are common to any biosample and are broadly grouped under four categories namely, the factors of teeth, donor, environment and analytical methods. How best the influencing factors to be considered during analysis, are discussed. It is elucidated that standardized method of analysis with quality assurance and precision will reduce the ambiguity of comparison of inter-laboratory measurement. When the merits and demerits of element measurements are evaluated, it is recognized that except a hurdle of difficult specific sampling, many advantages make teeth an attractive material for environmental health monitoring of population and for assessment of element status of deficiency and excess due to differential exposure. The available data of tooth elements are lesser in comparison to data of blood and hair;further studies are required for reference values of others elements and for distribution pattern in different conditions, parts and types of teeth.
