Objective To explore the effect of rolling compression loading bioreactor on chondrogenesis of rabbit bone marrow mesenchymal stem cells (BMSCs) with different loading parameters. Methods BMSCs were isolated from New Zealand rabbits, aged 2.5 months. BMSCs at passage 3 were used to prepare BMSCs-agarose gels (4 mm in diameter and height, respectively). Samples were divided into 8 groups: 10% (group A1), 20% (group A2), and 30% (group A3) compression groups (0.4 Hz, 3 h/ d) and 20 minutes (group B1), 3 hours (group B2), and 12 hours (group B3) rolling time groups and static culture (control groups). The living cell rate, the collagen type II and Aggrecan gene expressions, and glycosaminoglycan (GAG) content were determined, and histological staining was done at 24 hours, 7 days, 14 days, and 21 days after culture. Results At 14 and 21 days, the living cell rates of groups A1 and A2 were significantly higher than that of group A3 (P lt; 0.05), groups B1 and B2 were significantly higher than group B3 (P lt; 0.05). Collagen type II and Aggrecan gene expressions of the experimental groups at each time point were significantly higher than those of the control groups (P lt; 0.05); at 14 and 21 days, collagen type II and Aggrecan gene expressions of groups A1 and A2 were significantly higher than those of group A3, and groups B1 and B2 were also significantly higher than group B3 (P lt; 0.05). At 14 and 21 days, the GAG contents of groups A1 and A2 were significantly higher than those of group A3 (P lt; 0.05); groups B1 and B2 were also significantly higher than group B3 (P lt; 0.05). At 21 days, toluidine blue staining showed that obvious blue-staining and even cartilage lacunae were seen in groups A2 and B2, but light and quite rare blue-staining in groups A1, A3, B1, and B3. Conclusion The rolling compression loading bioreactor has great promotion effect on chondrogenesis of rabbit BMSCs with rolling parameters of 0.4 Hz, 3 hours, and 20% compression.
目的 探讨儿童气道异物的诊断、治疗及并发症发生的原因，以减少误诊及降低并发症的发生率。 方法 回顾分析2009年1月－2010年8月经病史、症状、体征及辅助检查（胸部X线检查或CT扫描）初诊为气道异物的317例患儿的临床资料。所有患儿均行支气管镜检查，明确有异物者行异物取出术，对术中、术后并发症的原因和处理方法进行总结。 结果 本组患者中有105例（33.1%）患儿曾被误诊为支气管肺炎或其他呼吸系统疾病，经支气管镜检及异物取出术后，出现并发症者共35例，包括：喉痉挛8例（22.8%），支气管痉挛6例（17.1%），支气管黏膜出血12 例（34.3%），皮下气肿8例（22.8%），死亡1例（2.8%）。 结论 儿童气道异物一经确诊或高度怀疑，应尽快行支气管镜检查，以保持呼吸道通畅。手术操作应轻柔准确，并注意观察患儿全身状况，是减少并发症的关键。