ObjectiveTo study the preparation method of acellular dermal matrix (ADM) for cartilage tissue engineering and analyze its biocompatibility. MethodsThe dermal tissues of the calf back were harvested, and decelluarized with 0.5% SDS, and the ADM was reconstructed with 0.5% trypsin, cross-linked with formaldehyde, and modified with 0.5% chondroitin sulfate which can promote the proliferation of chondrocytes. And the porosity, cytotoxicity, and biocompatibility were determined. Co-cultured 2nd passage chondrocytes and bone marrow stromal cells in a proportion of 3 to 7 were used as seed cells. The cells were seeded on ADM (experimental group) for 48 hours to observe the cell adhesion. The expressions of mRNA and protein of collagen type Ⅱ were tested by RT-PCR and Western blot methods, respectively. And the expressions were compared between the cells seeded on the scaffold and cultured in monolayer (control group). ResultsAfter modification of 0.5% trypsin, the surface of ADM was smooth and had uniform pores; the porosity (85.4%±2.8%) was significantly higher than that without modification (72.8%±5.8%) (t=-4.384, P=0.005). The cell toxicity was grade 1, which accords to the requirements for cartilage tissue engineering scaffolds. With time passing, the number of inflammatory cells decreased after implanted in the back of the rats (P<0.05). The scanning electron microscope observation showed that lots of seed cells adhered to the scaffold, the cells were well stacked, displaying surface microvilli and secretion. The expressions of mRNA and protein of collagen type Ⅱ were not significantly different between experimental and control groups (t=1.265, P=0.235;t=0.935, P=0.372). ConclusionThe ADM prepared by acellular treatment, reconstruction, cross-linking, and modification shows perfect characters. And the seed cells maintain chondrogenic phenotype on the scaffold. So it is a proper choice for cartilage tissue engineering.
【Abstract】 Objective To produce a new bone tissue engineered carrier through combination of xenograft bone (X)and sodium alginate (A) and to investigate the biological character of the cells in the carrier and the abil ity of bone-forming in vivo, so as to provide experimental evidence for a more effective carrier. Methods BMSCs were extracted from 2-week-old New Zealand rabbits and the BMSCs were induced by rhBMP-2 (1 × 10-8mol/L). The second generation of the induced BMSCs was combined with 1% (V/W) A by final concentration of 1 × 105/mL. After 4-day culture, cells in gel were investigated by HE staining. The second generation of the induced BMSCs was divided into the DMEM gel group and the DMEM containing 1% A group. They were seeded into 48 well-cultivated cell clusters by final concentration of 1 × 105/mL. Seven days later, the BMP-2 expressions of BMSCs in A and in commonly-cultivated cells were compared. The second generation of the induced BMSCs was mixed with 2% A DMEM at a final concentration of 1 × 1010/mL. Then it was compounded with the no antigen X under negativepressure. After 4 days, cells growth was observed under SEM. Twenty-four nude mice were randomly divided into 2 group s (n=12).The compound of BMSCs-A-X (experimental group) and BMSCs-X (control group) with BMSCs whose final concentrat ion was 1 × 1010/mL was implanted in muscles of nude mice. Bone formation of the compound was histologically evaluated by Image Analysis System 2 and 4 weeks after the operation, respectively. Results Cells suspended in A and grew plump. Cell division and nuclear fission were found. Under the microscope, normal prol iferation, many forming processes, larger nucleus, clear nucleolus and more nuclear fission could be seen. BMP-2 expression in the DMEM gel group was 44.10% ± 3.02% and in the DMEM containing 1% A group was 42.40% ± 4.83%. There was no statistically significant difference between the two groups (P gt; 0.05). A was compounded evenly in the micropore of X and cells suspended in A 3-dimensionally with matrix secretion. At 2 weeks after the implantation, according to Image Analysis System, the compound of BMSCs-A-X was 5.26% ± 0.24% of the totalarea and the cartilage-l ike tissue was 7.31% ± 0.32% in the experimental group; the compound of BMSCs-X was 2.16% ± 0.22% of the total area and the cartilage-l ike tissue was 2.31% ± 0.21% in the control group. There was statistically significant difference between the two groups (P lt; 0.05). At 4 weeks after the operation, the compound of BMSCs-A-X was 7.26% ± 0.26% of the total area and the cartilage-l ike tissue was 9.31% ± 0.31% in the experimental group; the compound of BMSCs-X was 2.26% ± 0.28% of the total area and the cartilage-l ike tissue was 3.31% ± 0.26% in the control group. There was statistically significant difference between the two groups (P lt; 0.05). Conclusion The new carrier compounding A and no antigen X conforms to the superstructural principle of tissue engineering, with maximum cells load. BMSCs behave well in the compound carrier with efficient bone formation in vivo.
Trabecular microstructure is an important factor in determining bone strength and physiological function. Normal X-ray and computed tomography (CT) cannot accurately reflect the microstructure of trabecular bone. High-resolution peripheral quantitative computed tomography (HR-pQCT) is a new imaging technique in recent years. It can qualitatively and quantitatively measure the three-dimensional microstructure and volume bone mineral density of trabecular bone in vivo. It has high precision and relative low dose of radiation. This new imaging tool is helpful for us to understand the trabecular microstructure more deeply. The finite element analysis of HR-pQCT data can be used to predict the bone strength accurately. We can assess the risk of osteoporosis and fracture with three-dimensional reconstructed images and trabecular microstructure parameters. In this review, we summarize the technical flow, data parameters and clinical application of HR-pQCT in order to provide some reference for the popularization and extensive application of HR-pQCT.
ObjectiveTo evaluate the safety and efficacy of microwave ablation (MWA) in the treatment of lung tumors.MethodsThe clinical data of 31 patients with lung neoplasms treated with MWA from January 2019 to August 2020 in a single center were retrospectively analyzed. There were 17 males and 14 females at an age of 63.4±10.4 years. The characteristics of the lesions, technical success rate, technical efficiency, local progression rate, adverse reactions and complications were recorded in detail.ResultsThere were 39 target lesions with an average diameter of 20.2±10.6 mm. A total of 36 MWA procedures were completed. The initial technical success rate was 84.6% (33/39), and the technical efficiency was 92.3% (36/39). The median postprocedure hospital stay was 2.0 (2.0, 3.0) d. A total of 12.9% (4/31) of the patients had local progression, and the local control rate was 87.1%. The main adverse reactions were pain (12/36, 33.3%), cough (6/36, 16.7%), post-ablation syndrome (6/36, 16.7%) and pleural effusion (3/36, 8.3%). The main complications were pneumothorax (11/36, 30.6%), hemorrhage (8/36, 22.2%), cavitation (2/36, 5.6%) and pulmonary infection (1/36, 2.8%). The median follow-up time was 13.0 (8.0, 18.0) months. No patient died during the follow-up.ConclusionMWA is safe and effective in the treatment of lung tumors with controllable complications. Successive researches with large sample, and medium and long-term follow-ups are needed to explore the significance of combined therapies.
ObjectiveTo investigate the feasibility and safety of DynaCT microwave ablation (MWA) guided by 3D iGuide puncture technology for lung cancer.MethodsThe clinical data of 19 patients with primary or metastatic lung cancer who underwent DynaCT MWA from June 2019 to December 2020 in our hospital were retrospectively analyzed, including 15 males and 4 females with an average age of 64.9±11.7 years. The technical success rates, adverse reactions and complications, postoperative hospital stay, and local therapeutic efficacy were recorded.ResultsTechnical success rate was 100.0%. The mean time required to target and place the needle was 15.7±3.7 min and the mean ablation time was 5.7±1.6 min. Thirteen patients underwent biopsy synchronously before the ablation, and 10 (76.9%) patients had positive pathological results. The main adverse reactions were pain (7/19, 36.8%), post-ablation syndrome (4/19, 21.1%) and cough (2/19, 10.5%). The minor complications were pneumothorax (6/19, 31.6%), hemorrhage (5/19, 26.3%), pleural effusion (2/19, 10.5%) and cavity (1/19, 5.3%). Three patients had moderate pneumothorax and received closed thoracic drainage. The median hospitalization time after ablation was 2.0 (2.0, 3.0) d, and no patient died during the perioperative period. The initial complete ablation rate was 89.5% (17 patients) and the incomplete ablation rate was 10.5% (2 patients) at 1-month follow-up, and no local progression was observed.ConclusionDynaCT MWA of lung cancer under the guidance of 3D iGuide system is safe and feasible with a high short-term local control rate, but the long-term efficacy remains to be further observed.