Rapamycin-induced β-Globin Family Locus Remodeling Regulates the Gene Switching Expression / 中国生物化学与分子生物学报

β-Thalassemia caused by abnormal coding of the β-globin gene is the most common hemoglobinopathy in many Asian countries. The in-depth study of the molecular basis and epigenetic mechanism of globin gene expression is the key to explore a new treatment for thalassemia. In this study, FAIRE (formaldehyde-assisted isolation of regulatory elements), 3C (chromosome conformation capture) and ChIP (Chromatin Immunoprecipitation) were used to investigate the three-dimensional interaction network of β-globin family gene loci and the molecular mechanism of functional regulation of gene expression during rapamycin-induced chromatin remodeling in CD4+ T cells. The results showed that the opening degree of globin gene chromatin, the interaction frequency between the gene promoter region and the regulatory element LCR (Locus control regions), and the enrichment efficiency of CTCF (CCCTC-binding factor) in the gene promoter region changed differently during the change of rapamycin treatment concentration from low to high, which led to the same change trend of the gene expression pattern. At the 10 nmol/ L concentration, chromatin accessibility and gene expression decreased (P < 0. 05). At 20 nmol/ L and 50 nmol/ L concentrations, chromatin accessibility increased and gene expression was up-regulated (P < 0. 05). In this study, the molecular mechanism of gene expression regulation of the β-globin family was expounded through this dynamic change process. Our work provides a theoretical and clinical practice basis for clinical precision treatment.

Arthroscopic Excision of Delayed Diagnosed Intra-articular Osteoid Osteoma of the Elbow: A Case Report

An intra-articular osteoid osteoma is a very rare cause of elbow pain, and its diagnosis and treatment remain challenging. Delayed diagnosis may lead to arthritic change of the joint. In this study, the authors present the occurrence of intra-articular osteoid osteoma in the right elbow of a 15-year-old male patient who presented with prolonged pain and limited motion owing to delayed diagnosis. After confirming the nidus of osteoid osteoma from radiographic evaluation, the lesion was completely removed arthroscopically. The patient presented a complete relief of symptoms and full range of motion. This is the first domestic report of successful arthroscopic treatment of an intra-articular osteoid osteoma of the elbow.

Diagnosis and Treatment of Bizarre Parosteal Osteochondromatous Proliferation / 대한정형외과학회잡지

PURPOSE: There have been a few reports of bizarre parosteal osteochondromatous proliferation (BPOP) in Korea to date. The purpose of this study was to investigate the etiology, diagnosis, treatment, and prognosis of BPOP and to report the clinical outcomes from a single institution. MATERIALS AND METHODS: Between 1999 and 2016, six patients who were diagnosed and treated operatively at Yeungnam University Medical Center were reviewed retrospectively. The analysis was performed using medical records, simple radiographs, magnetic resonance imaging (MRI), and pathology results, based on clinical and oncological results. All patients underwent surgical treatment for complete resection. We also analyzed one patient who was initially diagnosed with BPOP, showing different clinical features during the follow-up period. RESULTS: The age of patients ranged from 17 to 60 years. All patients did not show a history of trauma. All patients showed localized edema on the tumor lesion, and three patients also showed tenderness. The tumor lesions were distributed to the femur, tibia, and humerus. All patients underwent marginal resection or wide resection. The mean follow-up period was 50.3 months. There was a malignant change in one patient, but no recurrence or metastasis. CONCLUSION: In this study, there was no difference in the incidence of BPOP in accordance with sex. Moreover, there was no significant relationship between trauma and onset of BPOP. Unlike previous reports, no recurrence occurred after complete resection. If BPOP is diagnosed, it is necessary to consider the possibility of malignant change and distinguish it from other malignant tumors.

Diagnostic Tools for Acute Anterior Cruciate Ligament Injury: GNRB, Lachman Test, and Telos

PURPOSE: The purpose of this study is to compare the accuracy of the GNRB arthrometer (Genourob), Lachman test, and Telos device (GmbH) in acute anterior cruciate ligament (ACL) injuries and to evaluate the accuracy of each diagnostic tool according to the length of time from injury to examination. MATERIALS AND METHODS: From September 2015 to September 2016, 40 cases of complete ACL rupture were reviewed. We divided the time from injury to examination into three periods of 10 days each and analyzed the diagnostic tools according to the time frame. RESULTS: An analysis of the area under the curve (AUC) of a receiver operating characteristic curve showed that all diagnostic tools were fairly informative. The GNRB showed a higher AUC than other diagnostic tools. In 10 cases assessed within 10 days after injury, the GNRB showed statistically significant side-to-side difference in laxity (p<0.001), whereas the Telos test and Lachman test did not show significantly different laxity (p=0.541 and p=0.413, respectively). CONCLUSIONS: All diagnostic values of the GNRB were better than other diagnostic tools in acute ACL injuries. The GNRB was more effective in acute ACL injuries examined within 10 days of injury. The GNRB arthrometer can be a useful diagnostic tool for acute ACL injuries.

High Tibial Osteotomy versus Unicompartmental Knee Arthroplasty for Medial Compartment Arthrosis with Kissing Lesions in Relatively Young Patients

PURPOSE: The purpose of this study is to compare the clinical and radiographic outcomes of high tibial osteotomy (HTO) and unicompartmental arthroplasty (UKA) in advanced medial compartment arthritis accompanied by kissing lesions in relatively young patients. MATERIALS AND METHODS: Forty-five patients were divided into the HTO (n=23) and UKA (n=22) groups. Clinically, we evaluated the Lysholm knee scoring scale, visual analogue scale, Hospital for Special Surgery, and Western Ontario and McMaster Universities Osteoarthritis index scores preoperatively, 6 and 12 months postoperatively, and at the final follow-up. Radiographically, we measured the femoral-tibial angle and mechanical axis deviation preoperatively and at the final follow-up. RESULTS: All clinical outcomes gradually improved in both groups from the postoperative period to the final follow-up. At the final follow-up, all clinical outcomes were slightly better in the UKA group than in the HTO group; however, differences were not statistically significant. CONCLUSIONS: HTO is comparable to UKA in terms of clinical outcomes. Thus, the results of this study suggest that HTO might be a good alternative treatment to UKA for medial unicompartmental arthritis accompanied by kissing lesions in relatively young patients.

Transcriptome analysis of female and male flower buds of Idesia polycarpa Maxim. var. vestita Diels

Background: Idesia polycarpa Maxim. var. vestita Diels, a dioecious plant, is widely used for biodiesel due to the high oil content of its fruits. However, it is hard to distinguish its sex in the seedling stage, which makes breeding and production problematic as only the female tree can produce fruits, and the mechanisms underlying sex determination and differentiation remain unknown due to the lack of available genomic and transcriptomic information. To begin addressing this issue, we performed the transcriptome analysis of its female and male flower. Results: 28,668,977 and 22,227,992 clean reads were obtained from the female and male cDNA libraries, respectively. After quality checks and de novo assembly, a total of 84,213 unigenes with an average length of 1179 bp were generated and 65,972 unigenes (78.34%) could be matched in at least one of the NR, NT, Swiss-Prot, COG, KEGG and GO databases. Functional annotation of the unigenes uncovered diverse biological functions and processes, including reproduction and developmental process, which may play roles in sex determination and differentiation. The Kyoto Encyclopedia of Genes and Genomes pathway analysis showed many unigenes annotated as metabolic pathways, biosynthesis of secondary metabolites pathways, plant­ pathogen interaction, and plant hormone signal transduction. Moreover, 29,953 simple sequence repeats were identified using the microsatellite software. Conclusion: This work provides the first detailed transcriptome analysis of female and male flower of I. polycarpa and lays foundations for future studies on the molecular mechanisms underlying flower bud development of I. polycarpa.

The Clinical Characteristics, Treatments and Oncologic Outcomes of Chondroblastoma: Comparison with Giant Cell Tumor / 대한정형외과학회잡지

PURPOSE: The purpose of the study was to compare clinical, oncological outcomes between chondroblastoma and giant cell tumor. MATERIALS AND METHODS: This retrospective study reviewed 25 patients with histologically confirmed chondroblastoma of bone between 1998 and 2012. During the same period, 42 patients diagnosed as a giant cell tumor were also reviewed. We then analyzed clinical and oncological results of chondroblastoma compared with giant cell tumor. In chondroblastoma, 17 cases were male, and 8 cases were female, with a mean age of 20.6 years (range from 11 to 38 years). In giant cell tumor, 20 cases were male, and 22 cases were female, with a mean age of 39.26 years (from 17 to 75 years). All patients underwent surgical treatment that extended curettage with electrocauterization. After curettage, bony cavity was filled with autogenous bone, allogenic bone chip, bone cement, tricalcium phosphate, and so on. The results were compared in recurrence and metastatic rate. The minimum follow-up period was 1 year. RESULTS: In chondroblastoma, mean size was 2.18 cm (0.3 to 9.5 cm). Local recurrence and metastasis were absent. In giant cell tumors, mean size was 3.71 cm (0.3 to 11 cm). Local recurrence rate was 9.5% (4 of 42 cases) and there was one lung metastasis. CONCLUSION: Chondroblastoma is less invasive with better prognosis than giant cell tumor. Treatment of chondroblastoma and giant cell tumor is surgery. Electrocauterization as an adjuvant therapy showed good results.

Aqueous extracts of Tribulus terrestris protects against oxidized low-density lipoprotein-induced endothelial dysfunction / 中国结合医学杂志

<p><b>OBJECTIVE</b>To investigate the role of aqueous extracts of Tribulus terrestris (TT) against oxidized low-density lipoprotein (ox-LDL)-induced human umbilical vein endothelial cells (HUVECs) dysfunction in vitro.</p><p><b>METHODS</b>HUVECs were pre-incubated for 60 min with TT (30 and 3 μg/mL respectively) or 10(-5) mol/L valsartan (as positive controls) and then the injured endothelium model was established by applying 100 μg/mL ox-LDL for 24 h. Cell viability of HUVECs was observed by real-time cell electronic sensing assay and apoptosis rate by Annexin V/PI staining. The cell migration assay was performed with a transwell insert system. Cytoskeleton remodeling was observed by immunofluorescence assay. The content of endothelial nitric oxide synthase (eNOS) was measured by enzyme-linked immunosorbent assay. Intracellular reactive oxygen species (ROS) generation was assessed by immunofluorescence and flow cytometer. Key genes associated with the metabolism of ox-LDL were chosen for quantitative real-time polymerase chain reaction to explore the possible mechanism of TT against oxidized LDL-induced endothelial dysfunction.</p><p><b>RESULTS</b>TT suppressed ox-LDL-induced HUVEC proliferation and apoptosis rates significantly (41.1% and 43.5% after treatment for 3 and 38 h, respectively; P<0.05). It also prolonged the HUVEC survival time and postponed the cell's decaying stage (from the 69th h to over 100 h). According to the immunofluorescence and transwell insert system assay, TT improved the endothelial cytoskeletal network, and vinculin expression and increased cell migration. Additionally, TT regulated of the synthesis of endothelial nitric oxide synthase and generation of intracellular reactive oxygen species (P<0.05). Both 30 and 3 μg/mL TT demonstrated similar efficacy to valsartan. TT normalized the increased mRNA expression of PI3Kα and Socs3. It also decreased mRNA expression of Akt1, AMPKα1, JAK2, LepR and STAT3 induced by ox-LDL. The most notable changes were JAK2, LepR, PI3Kα, Socs3 and STAT3.</p><p><b>CONCLUSIONS</b>TT demonstrated potential lowering lipid benefits, anti-hypertension and endothelial protective effects. It also suggested that the JAK2/STAT3 and/or PI3K/AKT pathway might be a very important pathway which was involved in the pharmacological mechanism of TT as the vascular protective agent.</p>

Effect of β-sodium aescinate on hypoxia-inducible factor-1α expression in rat brain cortex after cardiopulmonary resuscitation / 世界急诊医学杂志（英文）

BACKGROUND: This study was undertaken to investigate the expression of hypoxia-inducible factor-1α (HIF-1α) in rat cerebral cortex and the effects of β-sodium aescinate (SA) administration after return of spontaneous circulation (ROSC).METHODS: Sixty rats were divided into three groups: SA group, injected intraperitoneally with SA instantly after ROSC; control group, injected intraperitoneally with normal saline; and sham-operated group, without cardiac arrest or SA. The cardiac arrest model was established using asphyxiation and intravenous potassium chloride. Blood was sampled 1, 6, 12, and 24 hours after ROSC. Protein and mRNA levels of HIF-1α, VEGF and EPO were detected in the cerebral cortex by immunohistochemistry and real-time RT-PCR; serum levels of NSE and S100β were determined by enzyme-linked immunosorbent assays.RESULTS: Serum S100β and NSE were signifi cantly increased in the control group versus the sham-operated group 1, 6, 12 and 24 hours after ROSC (P<0.05). Protein and mRNA levels of HIF-1α, VEGF and EPO were signifi cantly increased in the control rats (P<0.05). Serum NSE and S100β were significantly decreased in the SA group versus the control group 1, 6, 12 and 24 hours after ROSC (P<0.05). Protein and mRNA levels of HIF-1α, VEGF and EPO were signifi cantly increased in the SA group (P<0.05).CONCLUSIONS: The expression of HIF-1α is increased in rat cerebral cortex after ROSC, and SA up-regulates the expression of HIF-1α. The up-regulation of HIF-1α improves the resistance of the cortex to ischemia and hypoxia and contributes to neuroprotection, possibly because of up-regulation of EPO and VEGF expression.

Suppressing the growth of Hep-2 human laryngeal cancer cells by silencing survivin gene in vitro and in vivo / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To study the effect of silencing survivin on the growth of Hep-2 human laryngeal cancer cells in vitro and in vivo.</p><p><b>METHODS</b>Hep-2 cells were transfected with pGCsilencer-siRNA-survivin (psi-survivin)by Lipofectamine 2000. The mRNA and protein expressions of survivin were detected by semi-quantitative RT-PCR and Western blot, respectively. Cell proliferation activity was measured by MTT assay. Apoptosis was assessed by flow cytometry. The implanted tumors were formed from injected Hep-2 cells in nude mice. After the tumor formation, psi-survivin was injected into peritumor tissues. The growth of tumor were observed. The tumor volume was calculated and the tumor growth curve was plotted. The expression of survivin in tumor tissues was detected by Western blot. The tumor cell apoptosis was observed by Tunel staining.</p><p><b>RESULTS</b>The sequence-specific siRNA of survivin inhibited the expressions of survivin mRNA and protein. The inhibition rates of survivin mRNA and protein expression were 54.4% and 37.0% respectively. Also the growth of Hep-2 cells was inhibited significantly, with a decrease by 71.7%. By the day 32 of tumor growth, the mean tumor volumes were (1443.9 ± 230.5) mm(3) (x(-) ± s) in saline control group, (1348.5 ± 198.4) mm(3) in plasmid-negative control group, and (624.6 ± 188.4) mm(3) in psi-survivin group, respectively (t = -5.917, P < 0.01). In the implanted tumors injected with psi-survivin, survivin protein expression was down-regulated significantly, with a inhibition rate of 41.8%. Tunel staining showed the apoptosis occurred in the implanted tumors.</p><p><b>CONCLUSION</b>Silencing survivin could significantly inhibit the growth of Hep-2 human laryngeal cancer cells in vitro and in vivo.</p>

Studies on anti-hyperglycemic effect and its mechanism of Clinopodium chinense / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate the anti-hyperglycemic effect and its mechanism of ethanol extraction from Calamintha chinensis (EJCT).</p><p><b>METHOD</b>Fasting serum glucose (FSG) in normal mice was determined after oral administration of EJCT. Effects of EJCT on hyperglycemia mice induced by adrenaline were investigated by observing the contents of FSG and liver glucogen. Effect of EJCT on the diabetic mice induced by alloxan was investigated by observing the contents of FSG and the injured degree of pancreatic islet. The antilipid-peroxidation of EJCT on liver homogenate was measured by determination of malondiadehyde (MDA) induced by Fe2+/Cys.</p><p><b>RESULT</b>EJCT showed no obvious effect on FSG in normal mice. However, EJCT 300, 600 mg x kg(-1) could remarkably decrease the contents of FSG and increase liver glucogen in hyperglycemia mice induced by adrenaline. In diabetic mice induced by alloxan, EJCT 150, 300, 600 mg x kg(-1) could remarkably decrease the contents of FSG. The damage of pancreatic islet induced by alloxan was also significantly attenuated by EJCT. Furthermore, EJCT 30, 60, 90, 120 mg x L(-1) inhibited lipid peroxidation initiated by Fe2+/Cys in liver homogenate.</p><p><b>CONCLUSION</b>These results suggest that EJCT can significantly attenuate hyperglycemia in diabetic mice, which is probably due to decreasing the decomposition of liver glucogen, increasing the synthesis of liver glucogen, antioxidation and amelioration of damaged pancreatic islet.</p>

Role of bone marrow-derived mesenchymal stem cells in reduction of graft-versus-host disease by effecting CD4+CD25+ regulatory T cells in rats / 中国实验血液学杂志

The study was purposed to investigate the effects and mechanism of bone marrow-derived mesenchymal stem cells (MSCs) on graft-versus-host desease (GVHD) after allogeneic hematopoietic stem cell transplantation (allo-HSCT). The model of GVHD in rat had been established by allo-HSCT with donor derived T cells. The occurence of GVHD in recipients was observed in condition with or without donor derived MSC co-transplantation. Effects of MSCs on GVHD were analyzed by model rat survival rate and pathology. Proportions of CD4+CD25+ regulatory T cells were determined by using label spleen lymphocytes and thymocytes with double fluorescent-labeled antibodies and flow cytometry. The results showed that MSCs inhibited the lethal GVHD after HSC co-transplantation and increased the survival rate. The ratio of CD4/CD8 deceased in GVHD group in different levels, as compared with that in the experimental group. The proportion of CD4+CD25+ regulatory T cells of spleen lymphocytes was 31.55 +/- 7.58% and 20.90 +/- 1.90% in experimental and GVHD groups, respectively. Similarly, the proportion of CD4+CD25+ regulatory T cells of thymocytes was 93.20 +/- 2.69% and 57.17 +/- 6.79% in experimental and the GVHD groups, respectively. Meanwhile the proportion of CD4+CD25+ regulatory T cells was higher in experimental group than that in GVHD group. It is concluded that MSCs may prevent the lethal GVHD after allo-HSC co-transplantation and raise the survival rate of model rats by acting on the CD4+CD25+ regulatory T cells in vivo.

Analysis of the different effects of murine bone marrow endothelial cell conditioned medium on the growth of embryonic and adult hematopoietic stem/progenitor cells in vitro / 中国实验血液学杂志

In the present study, the effects of murine bone marrow endothelial cell conditioned medium (mBMEC-CM) on the growth of yolk sac and bone marrow hematopoietic stem/progenitor cells (HSPC) were investigated. Nonadherent cells of yolk sac and bone marrow were collected for semisolid culture assay of CFU-GM and HPP-CFC after being cultured in DMEM with 10% FBS, 10% mBMEC-CM and/or FL (5 ng/ml), TPO (2 ng/ml) for 24 hours. The number of CFU-GM and HPP-CFC was counted by day 7 and 14 respectively. Atlas cDNA Expression Array was used for analysis of cytokine receptor expression of yolk sac and bone marrow HSPC. The results showed that mBMEC-CM could support the expansion of CFU-GM and HPP-CFC in liquid culture system. The expansion effects of mBMEC-CM were enhanced by combination with FL and TPO. mBMEC-CM was more effective on expansion of bone marrow CFU-GM and HPP-CFC than that of yolk sac CFU-GM and HPP-CFC. The differential expression of cytokine receptors were detected between yolk sac and bone marrow HSPC. PDGF-Rbeta, PDGF-Ralpha and corticotropin releasing factor receptor (CRFR) were only expressed in yolk sac hematopoietic cells while IFN-gammaR, GM-CSFR, Dopamine D2R and follicle-stimulating hormone receptor were only expressed in bone marrow hematopoietic cells. In conclusion, mBMEC-CM could support the growth and proliferation of yolk sac and bone marrow HSPC, and this effect was further enhanced by addition of FL and TPO. mBMEC-CM was more effective on expansion of bone marrow HSPC than on expansion of yolk sac HSPC. The comparative study indicated that the different expressions of cytokine receptors existed between yolk sac and bone marrow hematopoietic cells, which might lead to the difference in expansion in vitro between embryonic and adult HSPC.

Y-chromosome-specific microsatellite variation in Li ethnic groups of Hainan Island, China / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>The study was conducted to reveal the distribution of genetic polymorphism of four Y chromosome specific short tandem repeat (Y-specific STR) loci in Li ethnic groups in Hainan Island, China.</p><p><b>METHODS</b>Four tetranucleotide STR loci were simultaneously amplified with fluorescently labeled primers, and genotypes were determined with an automated DNA sequencer.</p><p><b>RESULTS</b>Among 230 unrelated males, the alleles at the four Y-specific STR loci were composed of some complex repeat structure. 4,5,4,5 alleles were observed in loci DYS3891, DYS390, DYS391, DYS393 respectively. A set of human allele ladders for the typing of the four Y-specific STRs was obtained in Li ethnic population. Gene diversity index (D) and haplotype diversity data were estimated for the four Y-STRs.</p><p><b>CONCLUSION</b>The preliminary study indicates a reference population for detecting male migration events and should be useful in population genetics and forensic applications.</p>

Effects of murine bone marrow endothelial cell conditioned medium on the growth of yolk sac hematopoietic stem cells and progenitors / 中国医学科学院学报

<p><b>OBJECTIVE</b>To investigate the effects of murine bone marrow endothelial cell conditioned medium (mBMEC-CM) on the growth of yolk sac hematopoietic progenitors.</p><p><b>METHODS</b>The serum-free mBMEC-CM was obtained from subcultures of murine endothelial cell line derived from bone marrow which was established in our laboratory. The murine yolk sacs were harvested on day 8.5 postcoitus (pc) and incubated with 0.1% collagenase in 10% fetal calf serum at 37 degrees C for 40 minutes. Yolk sac cells were incubated in tissue culture dishes at 37 degrees C for 1 hour. Nonadherent cells were collected for semisolid culture assay of granulocyte-macrophage colony forming unit (CFU-GM) and high proliferative potential-colony forming cell (HPP-CFC) after being cultured in DMEM with 10% mBMEC-CM and 10% FBS for 24 hours. The number of CFU-GM and HPP-CFC was counted at day 7 and day 14 respectively.</p><p><b>RESULTS</b>The growth of CFU-GM and HPP-CFC was supported by mBMEC-CM with GM-CSF. mBMEC-CM could induce the proliferation and differentiation of yolk sac hematopoietic stem cells and progenitors in liquid culture system. The percentages of CFU-GM and HPP-CFC compared with the 0 hour control were (119.5 +/- 5.7)% and (130.8 +/- 9.8)% respectively after 24 hours liquid culture (P < 0.05). The expansion effects of mBMEC-CM on CFU-GM and HPP-CFC were enhanced by compounded with flt3 ligand (FL) and thrombopoietin (TPO). The percentages of CFU-GM and HPP-CFC compared with the 0 hour control were (132.0 +/- 6.2)% and (176.9 +/- 12.8)% respectively after 24 hours liquid culture (P < 0.01).</p><p><b>CONCLUSION</b>Murine bone marrow endothelial cell conditioned medium could support the growth and proliferation of yolk sac hematopoitic stem cells and progenitors, and this promoting effect was further enhanced by addition of FL and TPO.</p>

Osteogenic differentiation of murine yolk sac mesenchymal stem cells in vitro / 中国医学科学院学报

<p><b>OBJECTIVE</b>To investigate the potential of yolk sac mesenchymal stem cells in osteogenic differentiation.</p><p><b>METHODS</b>Murine yolk sacs were harvested on day 8.5 postcoitus, yolk sac cells were obtained after the yolk sacs were digested by 0.1% type I collagenase for 1 hour, the non-adherent cells were removed after being cultured for 1 hour. The adherent cells were cultured in DMEM containing of 5 ng/ml bFGF and 15% FBS, and passaged when they became subconfluent. The morphologic characteristics, and AKP, BMP-2, as well as type I, III collagen of the yolk sac adherent cells were observed and tested. The attached cells were treated with 10(-8) mol/L dexamethasone, 10 mmol/L beta-glycerophosphate, and 50 micrograms/ml vitamin C at passage 4. Alternations of morphological characteristic, AKP activity, collagen of type I, III and mineralization were detected.</p><p><b>RESULTS</b>Pure mesenchymal stem cells which were of spindle shape, uniform in size, positive in type I, III collagen staining and weak positive in AKP activity could be induced to pleomorphism osteoblast-like cells in vitro. The cells were transformed from spindle shape to polygonal cells which were positive in type I collagen, negative in type III collagen, strong positive in BMP-2, and positive in Von Kossa's stain at week 8. The polygonal cells could form nodular structure and their AKP activity was increased. All these were coincidence with the characters of osteoblast.</p><p><b>CONCLUSION</b>Yolk sac mesenchymal stem cell can be purified and induced to osteoblast in vitro.</p>

Osteogenic and neurogenic differentiation of human yolk sacm esenchymal stem cells / 中国病理生理杂志

AIM: To purify human yolk sac mesenchymal ste m cells (hYS-MSC) and investigate its osteogenic and neurogenic differentiation potentials. METHODS: hYS-MSC were separated from yolk sac and purified via p assage culture. The karyotype of hYS-MSCs was analyzed via G-banded characterist ics. Flow cytometric analysis was used to determine the cell cycle and phenotype of hYS-MSC. The AKP expression of hYS-MSC was also tested. Osteogenic different iation of hYS-MSCs was induced by 10 -8mol/L dexamethasone, 10 mmol/L ?-gl ycerophosphate and 50 mg/L vitamin C. Alizarin red S stain was used for identifi cation of mineralization. ?-mecaptoethanol or salviae miltiorrhizae were used t o induce neurogenic differentiation of hYS-MSCs. The expressions of NSE, NF and GFAP were identified by immunohistochemical method. RESULTS: hYS-MSCs could be purified at passages 2 or 3. The cell cycle analysis suggested that hYS-MSCs showed strong proliferational potentials by which the cells kept normal diploid karyotype during the in vitro cultur e. Flow cytometry showed the phenotype of purified hYS-MSCs was uniformly positi ve for CD29, CD44, CD105, and CD166, and negative for reactivity to antigens CD3 4, CD45, or CD86. hYS-MSCs were weakly but clearly positive in AKP. Osteogenic d ifferentiation was appeared after induction of osteogenic differentiation. hYS-M SCs, which were of spindle shape, uniform in size, were induced to pleomorphism osteoblast-like cells which expressed high level of AKP. Aggregates or nodules w ere formed at day 7 and calcium accumulation was detected by alizarin red S stai ning on day 10 or day 14. Neurogenic differentiation of hYS-MSCs was induced by ?-mecaptoethanol or salviae miltiorrhizae. NSE, NF or GFAP positive cells were detected by immunohistochemical staining. CONCLUSIONS: hYS-MSCs have strong proliferation potential and th e normal diploid karyotype is kept during the in vitro culture. The phenoty pe of hYS-MSCs is coincident with adult hMSCs. hYS-MSCs could be induced to dif ferent iate into osteogenic or neurogenic cells.