Induced pluripotent stem cells(iPSCs)are obtained by introducing exogenous genes or adding chemicals to the culture medium to induce somatic cell differentiation.Similarly to embryonic stem cells,iPSCs have the ability to differentiate into all three embryonic cell lines.iPSCs can differentiate into cardiac muscle cells through two-dimensional differentiation methods such as monolayer cell culture and co-culture,or through embryoid body and scaffold-based three-dimensional differentiation methods.In addition,the process of iPSCs differentiation into cardiac muscle cells also requires activation or inhibition of specific signaling pathways,such as Wnt,BMP,Notch signaling pathways to mimic the development of the heart in vivo.In recent years,suspension culturing in bioreactors has been shown to produce large number of iPSCs derived cardiac muscle cells(iPSC-CMs).Before transplantation,it is necessary to purify iPSC-CMs through metabolic regulation or cell sorting to eliminate undifferentiated iPSCs,which may lead to teratoma formation.The transplantation methods for iPSC-CMs are mainly injection of cell suspension and transplantation of cell patches into the infarcted myocardium.Animal studies have shown that transplantation of iPSC-CMs into the infarcted myocardium can improve cardiac function.This article reviews the progress in preclinical studies on iPSC-CMs therapy for acute myocardial infarction and discusses the limitations and challenges of its clinical application to provide references for further clinical research and application.

Objective:To investigate neuroprotective effect of alpinetin on ischemic stroke(IS)rats by regulating Shh/Gli1 signaling pathway.Methods:Fifteen rats were randomly collected as control group,remaining rats were used to construct an IS model.Rats that successfully modeling were randomly grouped into model group,alpinetin group(5 mg/kg),Shh/Gli1 signaling pathway inhibitor cycloparamide group(15 mg/kg)and alpinetin+cycloparamide group(5 mg/kg alpinetin+15 mg/kg cycloparamide),with 15 rats in each group,and administered once a day for two consecutive weeks,control group and model group were given equal amounts of physiological saline.Zea-Longa scoring method was applied to evaluate neural function;ELISA was applied to detect inflammatory factors levels;mass of brain tissue was weighed and water content of brain tissue was calculated;TTC staining was applied to measure volume of cerebral infarction;HE staining was applied to observe nerve cell damage;TUNEL staining was applied to detect neuronal apoptosis;qRT-PCR and Western blot were used to detect mRNA and protein expressions of Shh and Gli1.Results:There were no abnormalities in hippocampal tissue of control group,while hippocampal tissue structure of model group rats was abnor-mal,with disordered cell arrangement and nuclear pyknosis of nerve cells,cell damage rate,Zea-Longa score,infarct volume,IL-1β,IL-6,TNF-α,brain tissue water content,and cell apoptosis rate in model group were obviously higher than control group(P<0.05),mRNA and protein levels of Shh and Gli1 were obviously decreased(P<0.05);compared with model group,cells in alpinetin group were arranged more neatly,and phenomenon of neuronal cell nucleus pyknosis was improved,cell damage rate,Zea-Longa score,infarct volume,IL-1β,IL-6,TNF-α,brain tissue water content,and cell apoptosis rate were obviously decreased(P<0.05),mRNA and protein levels of Shh and Gli1 were obviously increased(P<0.05),trend of above indicators in cyclophosphamide group was opposite,ciclopramide reversed neuroprotective effect of alpinetin on IS rats.Conclusion:Alpinetin may exert neuroprotective effects on IS rats by activating Shh/Gli1 signaling pathway.

In the orthodontics process, intervention and sliding of an orthodontic bracket during the orthodontic process can arise large response of the labio-cheek soft tissue. Soft tissue damage and ulcers frequently happen at the early stage of orthodontic treatment. In the field of orthodontic medicine, qualitative analysis is always carried out through statistics of clinical cases, while quantitative explanation of bio-mechanical mechanism is lacking. For this purpose, finite element analysis of a three-dimensional labio-cheek-bracket-tooth model is conducted to quantify the bracket-induced mechanical response of the labio-cheek soft tissue, which involves complex coupling of contact nonlinearity, material nonlinearity and geometric nonlinearity. Firstly, based on the biological composition characteristics of labio-cheek, a second-order Ogden model is optimally selected to describe the adipose-like material of the labio-cheek soft tissue. Secondly, according to the characteristics of oral activity, a two-stage simulation model of bracket intervention and orthogonal sliding is established, and the key contact parameters are optimally set. Finally, the two-level analysis method of overall model and submodel is used to achieve efficient solution of high-precision strains in submodels based on the displacement boundary obtained from the overall model calculation. Calculation results with four typical tooth morphologies during orthodontic treatment show that: ① the maximum strain of soft tissue is distributed along the sharp edges of the bracket, consistent with the clinically observed profile of soft tissue deformation; ② the maximum strain of soft tissue is reduced as the teeth align, consistent with the clinical manifestation of common damage and ulcers at the beginning of orthodontic treatment and reduced patient discomfort at the end of treatment. The method in this paper can provide reference for relevant quantitative analysis studies in the field of orthodontic medical treatment at home and abroad, and further benefit to the product development analysis of new orthodontic devices.
Humans ; Periodontal Ligament/physiology* ; Orthodontic Wires ; Cheek ; Ulcer ; Tooth ; Finite Element Analysis

ObjectiveTo explore the mechanism of aerobic capacity on depression in school-age children, and the multiple mediators of the five dimensions of psychosocial functioning (emotional symptoms, conduct problems, peer problems, prosocial behavior and hyperactivity) between aerobic capacity and depression. MethodsFrom October to December, 2021, pupils of Grade two to Grade five from two primary schools were chester-sampled and investigated using 20-meter multistage shuttle run test, Depression Self-Rating Scale for Children, Self-reported Strengths and Difficulties Questionnaire. ResultsA total of 391 pupils underwent 20-meter multistage shuttle run test, and 312 out of them answering the questionnaires, and 294 questionnaires were valid. Aerobic capacity, depression, emotional symptoms, peer problems, prosocial behavior and hyperactivity were significantly correlated with each other (|r| > 0.127, P < 0.05) (except aerobic capacity and peer problems, and emotional symptoms and prosocial behavior). The results of the multiple mediation effect model showed that aerobic capacity could directly and negatively predict depression, and the mediating effects of emotional symptoms, peer problems, prosocial behavior and hyperactivity were significant, accounting for 34.37%, 12.54%, 34.06% and 17.80% of the total mediating effect, respectively. ConclusionThe aerobic capacity could not only directly affect depression of school-age children, but also improve their psychosocial functioning by reducing emotional symptoms, peer problems and hyperactivity, and increasing prosocial behavior, to indirectly affect their depression.

AIM: To study the pharmacokinetics (PK) of pazopanib tablets and explore the genetic mechanism of individual differences in drug metabolism primarily. METHODS: Fourteen healthy male subjects were respectively administrated with a single dose pazopanib tablet (200 mg) orally on the day of dosing, and their blood samples were collected from baseline to 96 hours. The serum concentration of pazopanib was measured by LC-MS/MS, the parameters of PK were calculated by winnonlin 6.3 software, and the gene polymorphism of cytochrome P450 3A4 (CYP3A4) was determined by snapshot method. RESULTS: The range of C

Objective: To establish a quantitative assay of serum Golgi protein 73 (GP73) using xMAP technology and evaluate its performance. Methods: Monoclonal antibodies against GP73 were prepared and purified, and antibody pair screening was performed by double-antibody sandwich enzyme-linked immunosorbent assay. The screened antibodies were used to construct a Luminex liquid chip detection system, and the analysis performance of the detection system was evaluated. The serum levels of GP73 were detected in 90 clinical samples from healthy controls and patients with chronic hepatitis B infection (CHB) and hepatocellular carcinoma (HCC). Results: Five anti-GP73 monoclonal antibodies were prepared and purified, and 5 antibody pairs were successfully screened. The Luminex liquid chip detection system of GP73 was successfully constructed using 8F10D1 and 10B9F11 antibody pairs. The analytical performance evaluation showed that the sensitivity of this system was 0.25 ng/ml and the dynamic range was 0.25-100 ng/ml. No cross reactivity was observed. The intra- and inter-assay variation for GP73 was <8% and <11%, respectively. The recovery was 83%-92%. The linear regression equation was y=1.141x+ 6.436 (r²=0.998 4, P<0.001). The GP73 concentrations in the serum samples of healthy control, CHB group, and HCC group were 42.8 (38.68, 55.90) ng/ml, 61.49 (43.59, 81) ng/ml, and 122.78 (49.36 liter, 264.55) ng/ml, respectively. The levels of GP73 in HCC group were significantly higher than those in CHB group and healthy controls (P<0.05). Moreover, the levels of GP73 in CHB group were significantly higher than those in healthy controls (P<0.05). Conclusions A liquid chip detection system of GP73 was successfully constructed. It provides a powerful tool for the clinical application of GP73 in the future.

Objective To compare the reprogramming effects and biological characteristics of two types of human odontogen-ic induced pluripotent stem cells(iPSCs).Methods Human dental pulp stem cells(DPSCs)and stem cells from apical papilla (SCAP)were isolated and primarily cultured.The Sendai reprogramming system was utilized to induce DPSCs and SCAP into iP-SCs.The morphology,reprogramming efficiency,reprogramming and time were compared between human DPSCs-iPSCs and SCAP-iPSCs.The SeV and exogenous transcriptional gene expression were detected by RT-PCR.Results Human DPSCs and SCAP were reprogrammed as iPSCs with classical ES-like clonal morphology.The reprogramming efficiencies were(0.68 ± 0.02)% and(0.7 ± 0.01)% respectively,the difference was not statistically significant(P>0.05).The reprogramming time was(26.0 ± 2.1)d and (27.0 ± 1.4)d respectively,the difference was not statistically significant(P>0.05).The RT-PCR results showed that no expres-sion of exogenous virus or transcriptional gene sequence in both iPSCs.Conclusion Human DPSCs and SCAP can be reprogrammed as virus-free and transgene-free iPSCs,which are the ideal sources of iPSCs.

OBJECTIVETo compare characterization of microRNAs (miRNAs) expression profiles of induced pluripotent stem cells (iPSCs) reprogrammed from human dental pulp stem cells (DPSCs) and stem cells from apical papilla (SCAP) and screen-specific microRNA.

METHODSHuman DPSCs and SCAP were reprogrammed into iPSCs using a Sendai virus vector. Total RNA of human DPSCs-iPSCs and SCAP-iPSCs were extracted. miRNAs were labeled and hybridized. Slides were scanned, and images were imported into GenePix Pro 6.0 for grid alignment and data extraction. Significant differentially expressed miRNAs between the two groups were identified using fold change and P-value and were analyzed.

RESULTSBoth human DPSCs and SCAP were successfully reprogrammed into iPSCs. Among miRNA genes analyzed by miRNA microarray, 68 were differentially expressed by more than 10-fold in DPSCs-iPSCs; 37 of these genes were up-regulated, and 31 were down-regulated. In SCAP-iPSCs, 107 genes were differentially expressed by more than 10-fold; 68 were up-regulated, and 39 were down-regulated. In both cells, only miR-302e was up-regulated, whereas 9 miRNAs were down-regulated: miR-29b-3p, miR-181b-5p, miR-4328, miR-22-5p, miR-145-5p, miR-4324, let-7b-5p, miR-181a-5p, and miR-27b-3p.

CONCLUSIONSMultiple miRNAs participated in reprogramming of human DPSCs and SCAP into iPSCs. Most miRNAs are related to cell cycle, transforming growth factor-β signaling pathways and epithelial-mesenchymal transition.

Cell Cycle ; Cell Division ; Dental Pulp ; Down-Regulation ; Electrodes ; Epithelial Cells ; Humans ; Induced Pluripotent Stem Cells ; MicroRNAs ; Taste Buds ; Up-Regulation

Objective To comparatively study the features of two reprogramming systems of induced pluripotent stem cells (iPSCs)from human dental origin.Methods Two kinds of reprogramming system,i.e.STEMCCA lentivirus /feed layer and Sen-dai virus /matrigel were used to induce human stem cells from apical papilla(SCAP)into iPSCs,respectively.The induction efficien-cies,workload of generating iPSCs,aneuploidy karyotype ratio,complexities of eliminating exogenous transcription factors and spe-cific markers expression were compared between these two systems.Results The STEMCCA reprogramming system required to prepare the feeder cell MEF.The reprogramming efficiency was 0.1%.Transcription gene-free iPSCs cells were obtained by the Cre-loxp enzyme digestion technique at the later stage.Sendai virus reprogramming system was feeder-free and the preparation of matrigel was quite simple with unified standard.The reprogramming efficiency was 0.7%,which was much higher than that of STEMCCA system(P <0.05).The exogenous virus and transgenes could be gradually eliminated after several passages of natural subclone.Conclusion The Sendai virus/matrigle reprogramming system is much more applicable for the induction of iPSCs from dental origin than the STEMCCA system.

Objective To compare the growth characteristics,proliferation and osteo/odontogenic differentiation capability of stem cells from human dental pulp (dental pulp stem cells,DPSCs) and apical papilla (stem cells from apical papilla,SCAP) in vitro.Methods Human dental pulp and apical papilla tissues were separated from impacted third molars of young healthy donors at the age of root development and digested by collagenase type Ⅰ and dispase type Ⅱ to derive primitive DPSCs and SCAP.Cells were then induced for osteo/odontongenic differentiation by medium containing β-glycerophosphate,dexamethasone and KH2PO4.Flow cytometry was utilized to test the expression of specific markers of stem cells,including CD24,CD34,CD45,CD90,CD105,CD146,STRO-1 and OCT-4.AR-S was used to display the mineralization structure and RT-PCR was applied to analyze the expression of bone sialoprotein (BSP),osteocalcin (OCN) and dentine sialophosphoprotein (DSPP).Results Both DPSCs and SCAP were positive for CD90,CD105,CD146,STRO-1 and OCT-4,in percentages varying according to cell type,without expression of CD34 or CD45.Only SCAP expressed CD24 positively.Both cells formed organized mineralization structure after 2 weeks of induction in time-dependent manner,with more mineralization by SCAP and expressed differentiation markers,including BSP,OCN and DSPP.Conclusion Human DPSCs and SCAP possess the characteristics of MSCs and could be differentiated into odontonblast-like cells in vitro.Both cells are approachable stem cell sources for dental tissue engineering.