Establishment of a platelet production model by bone marrow cavity transplantation of mouse primary megakaryocytes / 中华血液学杂志

Objective: To establish an intramedullary transplantation model of primary megakaryocytes to evaluate the platelet-producing capacity of megakaryocytes and explore the underlying regulatory mechanisms. Methods: Donor megakaryocytes from GFP-transgenic mice bone marrow were enriched by magnetic beads. The platelet-producing model was established by intramedullary injection to recipient mice that underwent half-lethal dose irradiation 1 week in advance. Donor-derived megakaryocytes and platelets were detected by immunofluorescence staining and flow cytometry. Results: The proportion of megakaryocytes in the enriched sample for transplantation was 40 to 50 times higher than that in conventional bone marrow. After intramedullary transplantation, donor-derived megakaryocytes successfully implanted in the medullary cavity of the recipient and produce platelets, which showed similar expression of surface markers and morphology to recipient-derived platelets. Conclusion: We successfully established an in vivo platelet-producing model of primary megakaryocytes using magnetic-bead enrichment and intramedullary injection, which objectively reflects the platelet-producing capacity of megakaryocytes in the bone marrow.

Ligand fishing: a strategy for rapidly screening bioactive compounds from organism extracts / 药学学报

Natural products are valuable resources for discovering new drugs. So far, screening bioactive compounds from organism extracts is still an important and challenging task. Traditional biometric guided method involves repeated fractionation steps and bioactivity tests, which are time-consuming, labor-consuming, and inefficient. Ligand fishing is a bioanalysis method for screening ligands from complex organism extracts based on intermolecular affinity interactions. It has the characteristics of strong specificity, high efficiency, and less requirement for sample pretreatment. In this review, we summarize the classification of ligand fishing strategy and its application in enzyme inhibitors screening. Finally, the development prospects of this technology are forecasted.

DMSO Promotes Hematopoietic Differentiation of Human Embryonic Stem Cells in vitro / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To explore the role of dimethyl sulfoxide (DMSO) in the hematopoietic differentiation of human embryonic stem cells (hESCs).</p><p><b>METHODS</b>The role of DMSO in hematopoietic differentiation of hESC was investigated by using a established stepwise hematopoietic differentiation system from hESC, immunofluorescouse assay and flow cytometry. Furthermore, the window phase of DMSO action was explored by adding it to the different stage of hematopoietic differentiation.</p><p><b>RESULTS</b>Immunofluorescence and flow cytometry analysis showed that DMSO significantly promoted the generation of CD43hematopoietic progenitor cells (HPC). The flow cytometry demonstrated that DMSO profoundly promoted the generation of APLNRlateral plate mesoderm cells and CD31CD34hemogenic endothelium progenitors (HEP). The addition of DMSO in the window phase of lateral plate mesoderm cell generation could markedly improve the generation of hematopoietic progenitor cells.</p><p><b>CONCLUSION</b>DMSO promotes hematopoietic differentiation of hESC through enhancing the generation of APLNR positive lateral plate mesoderm cells. The addition of DMSO in the window phase of lateral plate mesoderm cell generation can significantly improve the generation of hematopoietic progenitor cells.</p>

Inhibitory effect of KyoT2 overexpression on proliferation and migration of airway smooth muscle cells in mice with asthma / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate the effect of KyoT2 on the proliferation and migration of airway smooth muscle cells (ASMCs) in mice with asthma.</p><p><b>METHODS</b>Ovalbumin (OVA) was used to establish the asthmatic model of airway remodeling in BALB/c mice. ASMCs were isolated and cultured, and primarily cultured ASMCs were used as the control group. The expression of KyoT2 in ASMCs was measured in the control and asthma groups. After the ASMCs from asthmatic mice were transfected with pCMV-Myc (empty vector group) or pCMV-Myc-KyoT2 plasmid with overexpressed KyoT2 (KyoT2 expression group) for 48 hours, RT-PCR and Western blot were used to measure the mRNA and protein expression of KyoT2, the MTT assay and BrdU assay were used to measure the proliferation of ASMCs, and Transwell assay was used to measure the migration of ASMCs. Western blot was used to determine the effect of KyoT2 overexpression on the protein expression of RBP-Jκ, PTEN, and AKT.</p><p><b>RESULTS</b>Compared with the control group, the asthma group had significantly downregulated expression of KyoT2 in ASMCs, and the KyoT2 expression group had significantly upregulated expression of KyoT2 in ASMCs (P<0.05). Compared with the empty vector group, overexpressed KyoT2 significantly inhibited cell proliferation and migration, downregulated the expression of RBP-Jκ and AKT, and upregulated the expression of PTEN.</p><p><b>CONCLUSIONS</b>Overexpressed KyoT2 can inhibit the proliferation and migration of ASMCs through the negative regulation of RBP-Jκ/PTEN/AKT signaling pathway.</p>

Comparison of computed tomography versus magnetic resonance imaging in assessing radiofrequency ablation margins after radiofrequency ablation in patients with hepatocellular carcinomas / 中国医学科学院学报

<p><b>OBJECTIVE</b>To assess the diagnostic value of magnetic resonance imaging (MRI) in the follow-up of patients with hepatocellular carcinomas treated with radiofrequency ablation (RFA) and to compare it with that of computed tomography (CT).</p><p><b>METHODS</b>From December 2009 to September 2011, 40 patients (47 hepatocellular carcinomas) were treated with RFA after transcatheter arterial chemoembolization and underwent MRI and CT for follow-up. RFA margins were assessed on a five-point scale with receiver operating characteristic curve analysis. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were evaluated.</p><p><b>RESULTS</b>The interobserver agreement rate for MRI was significantly higher (Kappa=0.935) than for CT (Kappa=0.714; P < 0.05). The scores of 1 and 5 points for MRI, which confirms the presence or absence of residual tumor, accounted for 89.4% (84/94), while for CT accounting for only 31.9% (30/94). The area under the receiver operating characteristic curve of MRI was significantly higher than that of CT (P < 0.05), as were the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of detection rate (mean, 100%, 96.4%, 76.9%, 100%, and 96.8% for MRI, respectively, vs. 30.0%, 57.1%, 10.3%, 87.7%, and 63.8% for CT).</p><p><b>CONCLUSION</b>MRI is superior to CT in assessing the RFA margins in terms of the diagnostic accuracy and detection rate .</p>