Objective To prepare the silk fibroin (SF)-chitosan (CS) scaffolds by adjusting the mass ratio between CS and SF, and test and compare the properties of the scaffolds at different mass ratios. Methods According to the mass ratios of 6 ∶ 4 (group A), 6 ∶ 8 (group B), and 6 ∶ 16 (group C) between SF and CS, CS-SF scaffolds were prepared by freeze-drying method, respectively. The material properties, porosity, the dissolubility in hot water, the modulus elasticity, and the water absorption expansion rate were measured; the aperture size and shape of scaffolds were observed by scanning electron microscope (SEM). Density gradient centrifugation method was used to isolate the bone marrow mesenchymal stell cells (BMSCs) of 4-week-old male Sprague Dawley rats. The BMSCs at passage 3 were seeded onto 3 scaffolds respectively, and then the proliferation of cells on the scaffolds was detected by MTS method. Results The results of fourier transform infrared spectroscopy proved that with the increased content of CS, the absorption peak of random coil/α helix structure (1 654 cm-1 and 1 540 cm-1) constantly decreased, but the absorption peak of corresponding to β-fold structure (1 628 cm-1 and 1 516 cm- 1) increased. The porosity was 87.36% ± 2.15% in group A, 77.82% ± 1.37% in group B, and 72.22% ± 1.37% in group C; the porosity of group A was significantly higher than that of groups B and C (P lt; 0.05), and the porosity of group B was significantly higher than that of group C (P lt; 0.05). The dissolubility in hot water was 0 in groups A and B, and was 3.12% ± 1.26% in group C. The scaffolds had good viscoelasticity in 3 groups; the modulus elasticity of 3 groups were consistent with the range of normal articular cartilage (4-15 kPa); no significant difference was found among 3 groups (F=5.523, P=0.054). The water absorption expansion rate was 1 528.52% ± 194.63% in group A, 1 078.22% ± 100.52% in group B, and 1 320.05% ± 179.97% in group C; the rate of group A was significantly higher than that of group B (P=0.05), but there was no significant difference between groups A and C and between groups B and C (P gt; 0.05). SEM results showed the aperture size of group A was between 50-250 μm, with good connectivity of pores; however, groups B and C had structure disturbance, with non-uniform aperture size and poor connectivity of pores. The growth curve results showed the number of living cells of group A was significantly higher than that of groups B and C at 1, 3, 5, and 7 days (P lt; 0.05); and there were significant differences between groups B and C at 3, 5, and 7 days (P lt; 0.05). Conclusion The CS-SF scaffold at a mass ratio of 6 ∶ 4 is applicable for cartilage tissue engineering.
Objective To study repair of osteochondral defects by using composite of autologous BMSCs and chitosan/HAP (CS/HAP) bilayered scaffold in rabbits and its feasibil ity as osteochondral tissue engineering scaffolds. Methods CS/HAP bilayered scaffolds were produced with CS and HAP using a lyophil ization and sintering method. The pore size of the scaffold was observed by scanning electron microscopy (SEM). Anhydrous ethanol substitution method determined its porosity. BMSCs were isolated from bone marrow and cultured by general bone marrow methods. Both CD44 and CD45 on the BMSCs surface were detected with immunocytochemistry to identify BMSCs. Cell-scaffold complex was made with BMSCs as seed cells and CS/HAP bilayered scaffold as carrier by fibrin glue planting technique. The distribution ofBMSCs in CS/HAP scaffold was tested by SEM. The osteochondral defect (4 mm in diameter and 3 mm in height) model was made in the right knee joint of 36 Japanese white rabbits, which were randomly divided into 3 groups. Defects were repaired with CS/HAP and BMSCs composite ( group A, n=12) and with CS/HAP implants (group B, n=12); defects were not treated as a control (group C, n=12). Histological evaluation and gross observation were carried out at 6 weeks (n=6 in each group) and 12 weeks (n=6 in each group) postoperatively. Semi-quantitative histomorphological analysis was done to evaluate the repair cartilage tissue according to the modified Wakitani grading scale. Results CS/HAP bilayered scaffold possessed a porosity of 76.00% ± 5.01% and pore size of 200-400 μm (mean 300 μm ) in CS layer, and 72.00% ± 4.23% and 200-500 μm (mean 350 μm) in HAP layer, respectively. BMSCs formed colonies within 10-14 days. Immunocytochemistry results showed BMSCs had positive CD44 expression and negative CD45 expression. At 6 and 12 weeks after operation, gross and histological observation showed that the cartilage defects were fully filled with regenerated tissue, but bone defects were partially repaired in group A; the cartilage and bone defects were partially filled with regenerated tissue in group B and group C. The modified Wakitani grading scale were 5.17 ± 1.17 and 3.20 ± 0.75 in group A, 9.00 ± 0.63 and 6.00 ± 0.89 in group B, and 10.00 ± 0.89 and 9.60 ± 0.82 in group C at 6 weeks and 12 weeks postoperatively, respectively; showing significant differences between group A and groups B, C (P lt; 0.05). Conclusion The novel CS/HAP bilayered scaffold possesses porous structure and will possibly become a newbiomaterial of osteochondral tissue engineering.
ObjectiveTo investigate the expression of proapoptosis gene bad in intrahepatic cholangiocarcinoma (ICC) and its relationship to differentiation of the tumor.MethodsThe immunohistochemistry technique by Dako Envision system and rabbit antihuman bad polyclonal antibodies were adopted. The expression of bad was detected in 48 cases of ICC and 25 cases of control tissues.ResultsBad immunoreactivity in 48 cases of ICC was higher than that of bile duct epithelium in 25 cases of control tissues. And contrasted with 21 cases of well differentiated ICC, bad immunoreactivity was higher in 27 cases of middle and poor differentiated ICC.ConclusionThe expression of bad gene may be related to the differentiation of ICC.
ObjectiveTo compare the short-term outcomes of Da Vinci robot-assisted minimally invasive esophagectomy (RAMIE) and video-assisted thoracoscopic-laparoscopic minimally invasive esophagectomy (VAMIE) for esophageal cancer. MethodsA retrospective analysis was conducted on the data of patients with esophageal cancer admitted to Gansu Provincial People's Hospital from January 2021 to February 2025. Based on the surgical method, patients were divided into a RAMIE group and a VAMIE group. Both groups underwent standard McKeown three-incision surgery and systematic three-field lymph node dissection. Intraoperative blood loss, number of lymph nodes dissected, postoperative recovery indicators, and complication rates were compared. ResultsA total of 126 patients with esophageal cancer were included, of which 109 were male and 17 were female, with an average age of (64.6±8.8) years. The RAMIE group consisted of 36 patients and the VAMIE group 90 patients. There was no statistical difference in baseline indicators such as age, sex, and body mass index between the two groups (P>0.05). The difference in operation time between the two groups was not statistically significant [305.0 (280.0, 348.0) min vs. 300.0 (268.8, 340.0) min, P=0.457]. Compared with the VAMIE group, the RAMIE group had less intraoperative blood loss [100.0 (100.0, 120.0) mL vs. 100.0 (100.0, 200.0) mL, P=0.035], more intraoperative fluid infusion [(2244.7±610.3) mL vs. (1954.4±457.9) mL, P=0.013], a higher number of lymph nodes dissected [(27.9±10.6) nodes vs. (21.3±5.1) nodes, P<0.001], and the difference in the number of lymph node dissection groups was not statistically significant [8.0 (6.0, 8.0) groups vs. 7.0 (5.0, 8.0) groups, P=0.268]. In terms of postoperative recovery indicators, compared with the VAMIE group, the RAMIE group had shorter postoperative hospital stay [12.5 (9.0, 18.0) d vs. 17.0 (14.0, 22.0) d, P＜0.001] and shorter time with tubes [9.0 (8.0, 10.0) d vs. 10.0 (9.0, 12.0) d, P=0.007]. In terms of postoperative complications, the incidence of recurrent laryngeal nerve injury in the RAMIE group was significantly lower than that in the VAMIE group (2.8% vs. 16.7%, P=0.039), there was no statistical difference in pulmonary infection, anastomosis leakage, and incision infection between the two groups (P>0.05). The total hospitalization cost of the RAMIE group was significantly higher than that of the VAMIE group (P<0.001). ConclusionRAMIE has significant advantages over VAMIE in terms of intraoperative bleeding control, the number of lymph node dissections, postoperative recovery speed, and reducing the risk of incision infection and recurrent laryngeal nerve injury, with good safety and feasibility.