Clinical Orthopaedics

1. 磨损颗粒介导的骨质溶解-我们已经明确确定，骨祖细胞是受到金属骨科植入物材料产生的磨损颗粒影响的靶细胞类型之一。 颗粒处理的成体干细胞增殖减慢，诱导细胞凋亡，并抑制成骨分化。 我们最近的研究集中在细胞因子和缺氧在介导这些效应中的可能作用。 2. 骨科感染的分子检测-我们开发了基于聚合酶链反应（PCR）的技术，用于检测骨科相关组织中的细菌感染，特别是脓毒性关节炎和假体周围感染。通过靶向RNA（mRNA和rRNA），我们能够使用定量逆转录-PCR（qRT-PCR）来检测和评估活菌负荷。 正在分析利用滑液的临床系列，以测试该技术的潜在临床应用。 3. 超生理冲击介导的软骨退变模型-我们开发了一种可重复的、基于弹簧加载冲击器的兔模型，以研究冲击诱导的关节退变。 我们的重点是分析早期细胞反应，导致随后的骨关节炎样关节软骨退变。 4. 牵张成骨的动物模型-一种独特而有效的诱导出生后骨生长的方法，牵张成骨的机制还不清楚。 我们已经开发并完成了一项小鼠模型的研究，以分析伴随牵张成骨的基因表达事件。 此外，我们正在开发一种体外机械激活模型，使用培养细胞在2-D和3-D条件下模拟牵张成骨。 5. 氨基葡萄糖作为软骨保护剂-营养药物，氨基葡萄糖，已被广泛用于关节疼痛和其他相关疾病状态。 然而，其作用机制仍然难以捉摸。 我们已经研究了葡萄糖胺在阻断白细胞介素-1 β的软骨破坏活性中的功效。 我们的研究结果表明，早期或伴随治疗与生理浓度的葡萄糖胺有效地抑制有害影响的促炎细胞因子。

1. Wear particle mediated osteolysis - We have clearly established that osteoprogenitor cells represent one of the target cell types dramatically affected by the presence of wear debris particles derived from metallic orthopaedic implant materials. Particle treated adult stem cells slow down in their proliferation, are induced to undergo apoptosis, and are inhibited in osteogenic differentiation. Our recent study focuses on the possible role of cytokines and anoxia in mediated these effects. 2. Molecular detection of orthopaedic infections - We have developed polymerase chain reaction (PCR)-based technologies for the detection of bacterial infection in orthopaedically relevant tissues, specifically septic arthritis and periprosthetic infection. By targeting RNA, both mRNA and rRNA, we are able to use quantitative reverse transcription-PCR (qRT-PCR) to detect as well as assess the viable bacterial load. A clinical series utilizing synovial fluid is being analyzed to test potential clinical application of the technology. 3. Supraphysiological impact mediated cartilage degeneration model - We have developed a reproducible, spring-loaded impactor based rabbit model to study impact-induced articular degeneration. We are focusing on the analysis of early cellular responses that lead to subsequent osteoarthritis-likd articular cartilage degeneration. 4. Animal model of distraction osteogenesis - A unique and effective procedure to induce postnatal bone growth, the mechanism of distraction osteogenesis is not well understood. We have developed and completed a study of a mouse model to analyze the gene expression events accomanying distraction osteogenesis. In addition, we are developing an in vitro mechanical activation model using culture cells in 2-D and 3-D conditions to simulate distraction osteogenesis. 5. Glucosamine as a chondroprotecive agent - The nutriceutical, glucosamine, has been widely used for joint pain and other related disease states. However, the mechanism of action remains elusive. We have investigated the efficacy of glucosamine in blocking the chondrodestructive activity of interleukin-1 beta. Our results showed that early or concomitant treatment with physiological concentrations of glucosamine effectively suppress the deleterious effects of the pro-inflammatory cytokine.