BACKGROUND:Kalikrein 1 is an important component of the kalikrein-kinin system. Studies have shown that kalikrein can protect the cardiovascular system by promoting angiogenesis and inhibiting myocardial inflammation, but there is no report on its effect on inducing differentiation of stem cels. OBJECTIVE: To determine the transfection efficiency of kalikrein 1 adenoviral vector in rat bone mesenchymal stem cels. METHODS:Using adenovirus as a vector, the target gene kalikrein 1 was transfected into rat bone marrow mesenchymal stem cels. Fluorescence microscopy, MTT method and flow cytometry were used to investigate the effect of transfection and determine the optimal multiplicity of infection. RESULTS AND CONCLUSION:Adenovirus carrying kalikrein 1 was successfuly transfected into rat bone marrow mesenchymal stem cels. Results from flow cytometry showed that the transfection efficiency was associated with the multiplicity of infection. When the multiplicity of infection was 150, the transfection efficiency was 80.8%. MTT results showed that when the multiplicity of infection was 200, the cel growth was inhibited remarkably. These findings indicate that adenovirus-mediated kalikrein 1 can be successfuly transfected into rat bone marrow mesenchymal stem cels with the optimal multiplicity of infection=150.

BACKGROUND: It has been found that vascular endothelial growth factor can induce the differentiation of bone marrow mesenchymal stem cells into endothelial cells, but can the vascular endothelial growth factor gene promote the differentiation of bone marrow mesenchymal stem cells into vascular endothelial cells in the damaged organ under the hypoxic environment? OBJECTIVE: To observe whether human bone marrow mesenchymal stem cells induced by vascular endothelial growth factor could differentiate into vascular endothelial cells under hypoxia. METHODS: The third passage of human bone marrow mesenchymal stem cells were cultured in vitro. Cells in the control group were cultured with conventional culture medium, while those in experimental group were cultured with adenovirus vector containing vascular endothelial growth factor in 5% O2. After 2 weeks of culture, morphological observation and surface-related molecular detection were performed. The levels of vascular endothelial growth factor and endothelial nitric oxide synthase were detected by ELISA. The expression of endothelin and prostacyclin was detected by RT-PCR and western blot assay. RESULTS AND CONCLUSION: (1) The number of cells in the control group was more than that in the experimental group. The cells in the control group were crowded and arranged irregularly, showing a fiber-like growth, while those in the experimental group were mostly triangular or polygonal, exhibiting a colony-like growth. (2) CD31 was negative in the control group, while CD105 was positive and the positive rate was 99.7%, indicating that the cells still showed the phenotype of bone marrow mesenchymal stem cells. The positive rate ofCD31 was significantly increased to 30.33% in the experimental group and the positive rate of CD105 expression was decreased to 58.11%, indicating a typical phenotype of endothelial cells. (3) Compared with the control group, the expression of endothelin, vascular endothelial growth factor and endothelial nitric oxide synthase increased significantly in the experimental group (P < 0.05), and the expression of prostacyclin decreased significantly (P < 0.05). All these findings indicate that vascular endothelial growth factor can promote the differentiation of human bone marrow mesenchymal stem cells into vascular endothelial cells under hypoxia.

Objective:To measure the pubo-femoral distance of hips of the infants diagnosed with Graf type Ⅰ by high frequency ultrasound.Methods:A total of 1 084 infants(2 168 hips) diagnosed with Graf type Ⅰ by ultrasonography were collected in Beijing Jishuitan Hospital from June 2019 to May 2020. The ultrasonographic examinations included Graf method and pubo-femoral distance measurement. The 95% medical reference value was adopted to confirm range of normal values of the pubo-femoral distance. And the differences of the pubo-femoral distance between different gender, age and bilateral hip were compared.Results:The pubo-femoral distance of hips diagnosed with Graf type Ⅰ was (0.27±0.06)cm, the pubo-femoral distance of males was(0.27±0.06)cm, the pubo-femoral distance of females was (0.27±0.07)cm. The 95% medical reference value was 0.15-0.38 cm. The 95% medical reference value of males was 0.15-0.39 cm, and the 95% medical reference value of females was 0.13-0.41 cm. There were no significant differences between the sexes or between the age(all P>0.05). The difference between the bilateral hip joints from the same infant was statistically significant[(0.274±0.064)cm vs (0.265±0.064)cm, P<0.05]. Conclusions:The 95% medical reference value of hip diagnosed with Graf type Ⅰ is 0.15-0.38 cm.

Objective:To investigate the effect of miRNA-186-3p (miR-186-3p) on the apoptosis, immigration and invasion of cervical cancer CaSki cells and its relationship with transforming growth factor-β (TGF-β)-Smad signaling pathway.Methods:Plasmids containing miR-186-3p suppressor gene and miR-186-3p mimics were transfected into cervical cancer CaSki cells, namely miR-186-3p-I group and miR-186-3p-M group, respectively. In addition, CaSki cells transfected with empty plasmids were used as control (miR-186-3p-group C). Flow cytometry was used to detect the apoptosis rate of each group, and Transwell method was used to detect the migration and invasion ability of each group. Western blotting was used to detect the expression level of TGF-β-Smad signaling pathway related proteins. The target genes of miR-186-3p were predicted by using Starbase software and verified by using dual luciferase reporter gene assay.Results:The apoptosis rate of miR-186-3p-M group was lower than that of miR-186-3p-I group and miR-186-3p-C group [(7.5±3.2)% vs.(13.9±0.7)%, (12.7±0.6)%, all P < 0.05]. The number of migrating cells in miR-186-3p-M group [(218±25) vs. (168±13), (175±13), both P < 0.001] and the number of invasive cells in miR-186-3p-I group and miR-186-3p-C group were higher than those in miR-186-3p-I group and miR-186-3p-C group [(165±21) vs. (130±11), (142±12), all P < 0.001]. The relative expression levels of TGF-β, Smad2, Smad3, phosphorylated Smad2 (p-Smad2) and phosphorylated Smad3 (p-Smad3) in miR-186-3p-M group were the lowest, and the differences were statistically significant compared with the other two groups (all P < 0.001). Starbase software was used to predict the complementary binding of miR-186-3p to XIST RNA. Dual luciferase reporter assay showed that the relative luciferase activity of cells co-transfected with XIST wild-type vector and miR-186-3p mimic plasmid was lower than that of cells co-transfected with XIST wild-type vector and miR-186-3p empty plasmid ( P < 0.001). Conclusion:miR-186-3p may directly bind to XIST RNA and down-regulate the activity of TGF-β-Smad signaling pathway, thereby enhancing the immigration, apoptosis and invasion activities of cervical cancer CaSki cells.

Objective:To explore the high-frequency ultrasonographic and clinical features of superficial intravascular tumors.Methods:Thirteen superficial intravascular tumor patients who underwent ultrasound examination form Beijing Jishuitan Hospital during 2016-2020 were retrospectively analyzed. The location, anatomic blood vessels, shape, size, boundary, internal echo, blood flow and clinical characteristics of the tumors were analyzed.Results:Among the 13 cases, most of the tumors were oval like or long strip, and a few were round like. All 11 cases of primary intravascular tumors showed hypoechoic mass; 2 cases of intravascular metastasis or recurrence showed solid hypoechoic with hyperechoic mass. Arterial blood flow spectrum was detected in 12 cases. Two patients with glomus tumor showed typical tenderness at the fixed point. Two patients had a history of bone tumors in the upper or lower extremities.Conclusions:High frequency ultrasound can clearly recognize the location of the superficial intravascular tumors, describe the morphological characteristics and sonographic features of the tumor, then help to make a more accurate qualitative diagnosis.

Objective:To discuss the value of pubo-femoral distance(PFD) in the diagnosis of infants with developmental dysplasia of the hip(DDH).Methods:Nine hundred and thirty-one infants with DDH and normal infants diagnosed by clinical examination and ultrasonography were involved from February 2022 to June 2023 in Beijing Jishuitan Hospital. The ultrasonographic examination included Graf method and pubo-femoral distance measurement. Statistical analysis was made on the measurements of PFD of different types of hips.Results:Among all the hips, 1 359 hips were Graf type Ⅰ, 274 hips were Graf type Ⅱa, 166 hips were Graf type Ⅱb, 31 hips were Graf type Ⅱc, 7 hips were Graf type D, 13 hips were Graf type Ⅲ, and 12 hips were Graf type Ⅳ. The PFD of these hips were (0.34±0.07)cm, (0.35±0.08)cm, (0.35±0.08)cm, (0.51±0.11)cm, (0.67±0.09)cm, (0.95±0.26)cm, (1.27±0.30)cm, respectively. There was no significant difference in PFD between hips of Graf Ⅰ, Graf Ⅱa and Graf Ⅱb ( P>0.05), but there was significant difference in PFD between hips of the other Graf types ( P<0.05). The area under curve(AUC) of the PFD for the diagnosis of stability of the hips in infants was 0.959 with the cut-off value of 0.435 cm, the sensitivity and specificity were 88.9% and 90.4%, respectively. Conclusions:The PFD has great value in the evaluation of the stability of hip joint, and the cut-off value is 0.435 cm.