3D printed Mg-incorporated polycaprolactone scaffolds for repairing rat skull defects / 口腔疾病防治

Objective@#To evaluate the bone repair effect of 3D-printed magnesium (Mg)-loaded polycaprolactone (PCL) scaffolds in a rat skull defect model.@*Methods@#PCL scaffolds mixed with Mg microparticles were prepared by using 3D printing technology, as were pure PCL scaffolds. The surface morphologies of the two scaffolds were observed by scanning electron microscopy (SEM), and the surface elemental composition was analyzed via energy dispersive spectroscopy (EDS). The physical properties of the scaffolds were characterized through contact angle measurements and an electronic universal testing machine. This study has been reviewed and approved by the Ethics Committee. A critical size defect model was established in the skull of 15 Sprague-Dawley (SD) rats, which were divided into the PCL group, PCL-Mg group, and untreated group, with 5 rats in each group. Micro-CT scanning was performed to detect and analyze skull defect healing at 4 and 8 weeks after surgery, and samples from the skull defect area and major organs of the rats were obtained for histological staining at 8 weeks after surgery.@*Results@#The scaffolds had a pore size of (480 ± 25) μm, a fiber diameter of (300 ± 25) μm, and a porosity of approximately 66%. The PCL-Mg scaffolds contained 1.0 At% Mg, indicating successful incorporation of Mg microparticles. The contact angle of the PCL-Mg scaffolds was 68.97° ± 1.39°, indicating improved wettability compared to that of pure PCL scaffolds. Additionally, compared with that of pure PCL scaffolds, the compressive modulus of the PCL-Mg scaffolds was (57.37 ± 8.33) MPa, demonstrating enhanced strength. The PCL-Mg group exhibited the best bone formation behavior in the skull defect area compared with the control group and PCL group at 4 and 8 weeks after surgery. Moreover, quantitative parameters, such as bone volume (BV), bone volume/total volume (BV/TV), bone surface (BS), bone surface/total volume (BS/TV), trabecular thickness (Tb.Th), trabecular number (Tb.N) and bone mineral density (BMD), of skull defects were better than those in the other groups, indicating the best bone regeneration effect. H&E, Goldner, and VG staining revealed more mineralized new bone formation in the PCL-Mg group than in the other groups, and H&E staining of the major organs revealed good biosafety of the material.@*Conclusion@#PCL-Mg scaffolds can promote the repair of bone defects and have clinical potential as a new scaffold material for the repair of maxillofacial bone defects.

Expression of LOX and MMP-2 in gastric cancer tissue and the effects of LOX and MMP-2 on tumor invasion and metastasis / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To compare the expressions of lysyl oxidase (LOX) and matrix metalloproteinases-2 (MMP-2) in gastric cancer and pericancerous tissues, in gastric cancers with and without lymph node metastasis, and to analyze the effects of LOX and MMP-2 on tumor invasion and metastasis.</p><p><b>METHODS</b>Gastric cancer and pericancerous tissues were collected from 46 patients who underwent surgery. Levels of LOX and MMP-2 mRNA were detected by RT-PCR. Protein abundance of LOX and MMP-2 was examined using Western blot.</p><p><b>RESULTS</b>Expressions of LOX and MMP-2 mRNA, and protein in 46 gastric cancers were significantly higher than that in 46 pericancerous tissues. In gastric cancer with lymph node metastasis, the levels of LOX and MMP-2 mRNA and protein were higher than those in gastric cancers without lymph node metastasis (P < 0.05). In the groups of gastric cancer with lymph node metastasis, expression of LOX was positively correlated with MMP-2 protein expression (P < 0.01).</p><p><b>CONCLUSIONS</b>Expressions of LOX and MMP-2 in gastric cancer tissues are significantly higher than that in pericancerous tissues. The expressions of LOX and MMP-2 in gastric cancer with lymph node metastasis are higher than that in gastric cancer without lymph node metastasis. Expressions of LOX and MMP-2 are positively correlated. The results suggest that LOX and MMP-2 may promote the growth and metastasis of gastric cancer.</p>

Effect of lysyl oxidase on migration and adhesion of human gastric cancer HGC-27 cells in vitro / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To study the effects of lysyl oxidase (LOX) on the migration and adhesion of the human gastric cancer cell line HGC-27 cells in vitro.</p><p><b>METHODS</b>The human gastric cancer cell line HGC-27 cells were cultured in vitro, and treated with different concentration of β-aminopropionitrile (BAPN). The ability of migration was assessed by wound-healing assay. The ability of adhesion was detected by homogenous and heterogeneous adhesion experiments.</p><p><b>RESULTS</b>Compared that with 0 mmol/L BAPN, the ability of migration of the cells after treatment with 0.2 mmol/L BAPN was descended at 8, 24, 32 and 48 h; the number of cells with homogeneous adhesion was increased from (6.97 ± 0.07) × 10(3)/ml to (7.78 ± 0.11) × 10(3)/ml; and the number of cells with heterogeneous adhesion was decreased from (8.98 ± 0.15) × 10(3)/ml to (8.35 ± 0.10) × 10(3)/ml, both < 0.05. Compared with that of cells treated with 0 mmol/L and 0.2 mmol/L BAPN, the migration ability of cells after treatment with 0.3 mmol/L BAPN was descended at 8, 24, 32 and 48 h; the number of cells with homogeneous adhesion was raised to (8.02 ± 0.11) × 10(3)/ml and the number of cells with heterogeneous adhesion was down to (7.93 ± 0.07) × 10(3)/ml (P < 0.05).</p><p><b>CONCLUSION</b>LOX may promote the metastasis of cancer cells by enhancing invasion, increasing heterogeneous adhesion and decreasing homogeneous adhesion.</p>

Y Chromosomal STR Polymorphism in Northern Chinese Populations

Y chromosomal STRs show sufficient variability among individduals in a population and a high degree of geographical differentiation, such that their polymorphic character makes them especially suited for population genetic studies. To investígate the polymorphism of a set of 17 Y-STR loci in northern China, we genotyped the 17 Y chromosomal STR loci in a population sample of 377 unrelated males from eight ethnic populations in northern China. We calculated the haplotype frequencies, Rst value and carried out the analysis of molecular variance (AMOVA). We then drew the multidimensional scaling analysis (MDS) plot and phylogenetic tree based on the Rst value. All populations showed a high level of haplotype diversity, with low inter-population variance as measured by an analysis of molecular variance. However, the genetic distances were significant when the eight populations were compared to other populations. By MDS and the phylogenetic tree, we found that the eight populations had a close relationship and Xibo had a northeast origination.

The role of different needling manipulation in adjusting swallow-period obstacle of dysphagia after stroke / 中国针灸

<p><b>OBJECTIVE</b>To observe the effect of different needling manipulation in improvement of swallow-period obstacle of dysphagia after stroke.</p><p><b>METHODS</b>One hundred and eleven cases were randomly divided into a single Lianquan RN 23 shallow needling group (group A ), single Lianquan (RN 23) deep needling group (group A2) and Lianquan (RN 23) and para-Lianquan deep multi-needling group (group B). The therapeutic effect was investigated after continuous treatment for 14 days.</p><p><b>RESULTS</b>The total effective rate was 95. 0% in the group B, 65. 7% in the group A1 and 83. 3% in the group A2, with significant difference or very significant difference when the group B compared with the group A, and the group A, (P<0. 01 or P<0. 05); the cured and markedly effective rate was 82. 5% in the group B, 20. 0% in the group Al and 52. 8% in the group A2, with a very significant difference as the group B compared with the group A, and A2 (both P<O. 01). After treatment for 7 days, there were very significant differences in scores of swallow function as the group B compared with the group A, and A2 (both P<0. 01), indicating that the group B was better than the group A1 and AZ in improvement of sensitivity of swallow dysphagia.</p><p><b>CONCLUSION</b>Deep needling with multi-needles can significantly improve swallow-period obstacle of dysphagia after stroke with higher safety and rapid effect.</p>