ObjectiveTo investigate the feasibility of small molecule compound XAV939 to induce mouse embryonic stem cells (mESC) to differentiate into cardiac myocytes. MethodsWe revived and cultured undifferentiated mESC growing confluently on trophoderm made of mouse embryonic inoblast cell. The mESCs were digested by trypsin to form embryoid bodies (EBs) by handing drop method. After plated, EBs were induced by XAV939 to differentiate into cardiac myocytes. We observed the cardiac myocytes with lightmicroscopy and identified it with immunofluorescence method. Result The XAV939 can effectively induce mESC into cardiac myocytes with the mean efficiency rate of 71.85%±1.05%. The differentiated cardiac myocytes shrinked spanteously and rhythmicly. The cardiac troponin T as the special marker of cardiac myocyte was positive. ConclusionThe small molecule compound XAV939 could effectively induce mES cells into cardiac myocytes.
ObjectivesTo investigate the diagnostic value of different diffusion-weighted MRI (DWI) models between two Gaussian DWI models including mono-exponential and bi-exponential, and the non-Gaussian kurtosis model in poorly differentiated pancreatic ductal adenocarcinoma.MethodsSubjects comprised 52 patients with poorly differentiated pancreatic ductal adenocarcinoma which had been confirmed by surgery. All patients underwent DWI (1.5T, multi-b values: 0, 50, 100, 150, 200, 500, 800, 1000, 1 500, 2 000s/mm2). Mean values of DWI-derived metrics ADCstandard, ADCslow, ADCfast, f, MD, MK and ADCstandard were calculated from regions of interest in all tumours and non-tumorous parenchyma and compared. ANOVA and Mann Whitney U test was used to compare the MRI paremeters. ROC was used to evaluate the diagnostic efficiency.ResultsMean ADCstandard, ADCfast, f and MK values showed significant differences between tumours and non-tumorous parenchyma (P<0.05). AUC for ADCstandard, MD, ADCfast and f were 0.705, 0.665, 0.648, 0.614, respectively. The ROC curve integrated with ADCstandard and MD had better diagnostic efficiency (AUC was about 0.754).ConclusionsADCstandard, ADCfast, f and MK values can differentiate tumours from non-tumorous parenchyma. The combination of Gaussion distribution model and non-Gaussion distribution model has the potential to increase the diagnostic accuracy of DWI in patients with pancreatic ductal adenocarcinoma.
Objective To review the progress, methods and obstacles in the differentiation of embryonic stem cells(ESCs) into osteoblasts in vitro. Methods The recent literature concerned with the differentiation of ESCs into the osteoblasts was extensively reviewed and briefly summarized. Results ESCs was a good tool for derivation of obsteoblasts.Conclusion The study on the induction of ESCsinto the osteogenic lineage provides a model for analyzing the molecular processes of osteoblasts development in vivo and establishes the foundation for the use of ESCs in skeletal tissue repair.
The effects of all-trans retinoic acid (ATRA) on primary gastric carcinoma models made by subcutaneous implanting gastric cancer to mice were observed. Thirty-two cancer bearing nude mice were randomly divided into 4 groups: control group (group Ⅰ)， ATRA low dose feeding group (100μg/day， group Ⅱ), moderate dose feeding group (300μg/day， group Ⅲ), and high dose feeding group (1 000 μg/day, group Ⅳ). The alteration of tumor growth, morphology, cytobiology, and immuno-histochemical assay were perfermed. The results showed significant inhibition of tumor growth and inducing differentiation in the group Ⅲ and group Ⅳ as compared with group Ⅰ (Ｐ＜0.01),and inhibited expression of p53, p21 protein in implanted tumor. The authors consider that ATRA has some effects of growth inhibition and differentiation on gastric cancer cells in vivo, and these is related to the inhibition of expression p53 and p21 onco-gene of cancer cells and accelerate apoptosis of carcinoma cells.
Stem cells have been regarded with promising application potential in tissue engineering and regenerative medicine due to their self-renewal and multidirectional differentiation abilities. However, their fate is relied on their local microenvironment, or niche. Recent studied have demonstrated that biophysical factors, defined as physical microenvironment in which stem cells located play a vital role in regulating stem cell committed differentiation. In vitro, synthetic physical microenvironments can be used to precisely control a variety of biophysical properties. On this basis, the effect of biophysical properties such as matrix stiffness, matrix topography and mechanical force on the committed differentiation of stem cells was further investigated. This paper summarizes the approach of mechanical models of artificial physical microenvironment and reviews the effects of different biophysical characteristics on stem cell differentiation, in order to provide reference for future research and development in related fields.
ObjectiveTo explore the effects of concentrated growth factor (CGF) combined with mineralized collagen (MC) materials on the adhesion, proliferation, and differentiation of bone marrow mesenchymal stem cells (BMSCs) and their osteogenic effects in vivo, and to provide a theoretical basis for the combined application of CGF and MC materials in bone defect regeneration and repair.MethodsCGF was prepared from venous blood of healthy volunteers, and then CGF extracts (CGFe) were prepared. In vitro experiment: human BMSCs (hBMSCs) were divided into 4 groups. Groups A, B, and C were cultured with α-MEM medium [containing 10% fetal bovine serum (FBS) and 1% double antibody] containing 2%, 5%, and 10%CGFe, respectively; group D was cultured with α-MEM medium (containing 10%FBS and 1% double antibody) without CGFe. Scanning electron microscopy was used to observe the effect of CGFe on cell adhesion. Cell counting kit 8 (CCK-8) was used to detect the effect of CGFe on cell proliferation. After osteogenic induction, alkaline phosphatase (ALP) activity was detected and Western blot was performed to detect osteopontin (OPN) expression. In vivo experiment: Eighteen New Zealand big-eared rabbits were used to prepare circular bone defect models on the left and right mandibles, and implant CGF gel (prepared from autologous venous blood)+MC material (volume ratio 1∶1, experimental group) and simple MC material (control group), respectively. At 4, 8, and 12 weeks after operation, 6 rabbits were sacrificed respectively to obtain materials, and Micro-CT scanning was performed to observe the formation of new bone and material degradation in vivo.ResultsIn vitro experiments: Scanning electron microscopy showed that the cells of groups A, B, and C spread better on MC materials than group D, with more pseudopodia. CCK-8 method showed that different concentrations of CGFe could promote cell proliferation, and the absorbance (A) value of cells cultured for 2, 3, 5, and 7 days was in the order of group C>group B>group A>group D, the differences were significant (P<0.05). ALP activity test showed that its activity was proportional to the osteogenic induction time and CGFe concentration (P<0.05). Western blot analysis of osteogenic induction culture for 14 days showed that the relative expression of OPN protein in groups A, B, and C was significantly higher than that in group D, and the higher the CGFe concentration, the higher the relative expression of OPN protein (P<0.05). In vivo experiment: Micro-CT observation showed that the new bone formation and material degradation of the experimental group were better than those of the control group at 4, 8, and 12 weeks after operation. Quantitative detection showed that the volume of new bone volume, new bone volume fraction, trabeculae number, and trabecular thickness of the experimental group were significantly higher than those of the control group at each time point, the residual material volume, residual material volume fraction, and trabecular separation were significantly lower than those of the control group, all showing significant differences (P<0.05).ConclusionCGF can effectively promote the adhesion, proliferation, and osteogenic differentiation of BMSCs on MC materials, and 10%CGFe has the most significant effect. The combined application of CGF and MC material can significantly promote bone formation in vivo.
Objective To investigate the effects of growth differentiation factor 15 (GDF15) on lung adenocarcinoma bone metastasis in nude mice by regulating phosphatase and tensin homology/phosphatidylinositol 3 kinase/protein kinase B (PTEN/PI3K/AKT) signaling pathway. Methods The bone metastasis model of lung adenocarcinoma in nude mice was established and mice were randomly divided into Control group, sh-NC group, sh-GDF15 group, sh-GDF15+sh-NC group and sh-GDF15+sh-PTEN group. The changes of 50% pain withdrawl threshold (PWT) and thermal withdrawal latency (TWL) were observed. bone destruction was analyzed by Micro-CT. Bone morphology was observed by HE staining. The expression of osteoclast-related factors was detected by immunohistochemistry. The expression of PTEN/PI3K/AKT signaling pathway was detected by Western blot. Results The tibia tissue of nude mice in Control group and sh-NC group was destroyed, the continuity of bone cortex was interrupted, obvious bone tumor lesions were observed, the tumor cells were irregular in shape, densely distributed and disordered, and the nuclei were obviously deformed. Compared with sh-NC group, sh-GDF15 group had less tibial tissue destruction, the bone tumor cell density was significantly reduced, the pathological morphology was significantly improved, and 50% PWT, TWL, bone mineral density (BMD), trabecular bone volume/total volume (BV/TV), trabecular number (Tb.N), trabecular thickness (Tb.Th) and PTEN expression were increased, the expressions of trabecular separation (Tb.Sp), cathepsin K (CTSK), matrix metalloproteinase 9 (MMP-9), p-PI3K PI3K and p-Akt/Akt were decreased (P<0.05). Compared with sh-GDF15+sh-NC group, sh-GDF15+sh-PTEN group had severe tibial tissue damage, the bone tissue tumor cells were dense and the pathological injury was aggravated, and 50%PWT, TWL, BMD, BV/TV, Tb.N, Tb.Th and PTEN expression were decreased, the expressions of Tb.Sp, CTSK, MMP-9, p-PI3K /PI3K and p-Akt /Akt were increased (P<0.05). Conclusion GDF15 can promote bone metastasis of lung adenocarcinoma in nude mice, and its mechanism is related to inhibition of PTEN/PI3K/AKT signaling pathway.
ObjectiveTo explore the application value of carbon nanoparticles during radical operation of differentiated thyroid cancer (DTC).MethodsThe DTC patients underwent total thyroidectomy plus neck lymph node (area Ⅳ) dissection from September 2017 to September 2019 in this hospital were retrospectively collected, who were divided into observation group and control group according to using carbon nanoparticles or not during the operation. The operation related informations [operation time, intraoperative blood loss, total drainage volume on day 3 after operation, postoperative hospitalization time, number of lymph nodes dissection (area Ⅳ), lymph node metastasis rate, and rate of parathyroid glands resected by mistake during operation] and blood calcium (Ca2+) level and parathyroid hormone (PTH) level before and after (24 h and 1 month) operation were compared between the two groups.ResultsA total of 134 patients with DTC were collected, including 76 patients in the observation group and 58 patients in the control group. There were no significant differences in baseline data such as gender, age, etc. between the two groups (P>0.05). Although there were no significant differences in terms of operation time, intraoperative blood loss, total drainage volume on day 3 after operation, postoperative hospitalization time, lymph node metastasis rate between the two groups (P>0.05), the numbers of lymph node dissection and metastasis (area Ⅳ) were more and rate of parathyroid glands resected by mistake during operation was lower in the observation group as compared with the control group (P<0.05). On hour 24 after operation, the levels of Ca2+ and PTH in the observation group were higher than those in the control group (P<0.05). On month 1 after operation, the PTH level in the observation group was still higher than that in the control group (P<0.05), but there was no significant difference in Ca2+ level between the two groups (P>0.05). ConclusionCarbon nanoparticles can better protect the function of parathyroid gland during radical operation of DTC and clean neck lymph nodes more thoroughly.
Objective To isolate neural stem cells (NSCs) from rabbit retina and brain, and induce differentiation of those NSCs using different culture media. Methods Single-cell suspensions of retina and cerebral cortex were prepared from rabbit embryo, cultured in 5 types of different media to isolate the NSCs by continual passages. After 3 passages, NSCs were induced to differentiation in 2 types of different media for 8 to 10 days. NSCs and inducedretinal cells were examined by immunofluorescence and flow cytometry for the expression pattern of some specific antigens.Results Immunofluorescence showed that NSCs from retina and brain, cultured in serumfree media, both expressed Nestin partially. Flow cytometry showed that Nestin positive cells were significantly decreased while the Rhodopsin and Thy1.1 positive cells were increased after induction. Compared with the combined induction of alltrans retinoid acid (ATRA) and serum, 5%FBS (fetal bovine serum) led to higher expression of Rhodopsin（P＜0.01），but lower expression of Thy1.1（P=0.01）.Conclusion Serumfree media with N2, EGF, bFGF, LIF is the best for NSCs purification. Both induciton media can induce NSCs to differentiate.Retina NSCs have higher potentials to differentiate into retinal neuroepithelial cells than brain NSCs.
手術是治療分化型甲狀腺癌的重要手段和有效方法，已在我國各級醫院廣泛開展。但由于對疾病認識的不足和技術條件的限制，分化型甲狀腺癌的外科治療在不同地區、不同醫療機構和不同醫生之間存在著很大的差異，其治療結果也迥然不同。盡管目前對分化型甲狀腺癌的外科治療還存在一些不同的觀點和尚需進一步研究和探討的問題，但在很多方面已逐漸達成共識，治療方案也逐漸趨于規范化，現就以下幾個方面淺談加強分化型甲狀腺癌的規范化治療，旨在提高分化型甲狀腺癌的診治水平……