David A. Hart

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We characterized quantitatively the macrophage response following axonal injury in both the peripheral (PNS) and central nervous system (CNS) of adult mammals. A monoclonal antibody (ED-1) which stains monocytes, macrophages, and activated microglia was employed. In one model, Wallerian degeneration of the sciatic nerve was studied. An increase in the(More)
BACKGROUND Rotator cuff tears are a cause of pain and disability in the shoulder. The molecular changes associated with rotator cuff tearing are unclear. A subset of matrix metalloproteinases and tissue inhibitors of metalloproteinase, which are involved in extracellular matrix remodeling and degradation, were evaluated. HYPOTHESIS There would be an(More)
Knee joint laxity can result from soft tissue injury, such as a ligament tear, or from genetic factors such as joint hypermobility syndrome and various forms of Ehlers-Danlos Syndrome. The location of a subject's passive knee laxity along a continuous spectrum is dependent on the mechanical properties of the existing structures, and the increased motion(More)
BACKGROUND It has been speculated that the hormonal cycle may be correlated with higher incidence of ACL injury in female athletes, but results have been very contradictory. HYPOTHESIS Knee joint loads are influenced by knee joint laxity (KJL) during the menstrual cycle. STUDY DESIGN Controlled laboratory study. METHODS Serum samples and KJL were(More)
BACKGROUND Ligament injuries of the knee are common and, if severe, can predispose to joint pain, instability, reinjury, and, ultimately, osteoarthritis. Xenograft replacement of ligaments could have potential; however, a limited understanding of the immunology of ligament xenograft rejection has inhibited their use. The purpose of this study was to(More)
The aim of this study was to evaluate the effect of human serum (HS) on growth and differentiation capacity of human synovium-derived mesenchymal stem cells (MSC) in comparison to cells grown in fetal bovine serum (FBS). Human MSCs were isolated from the synovium of knee joints of three donors and the cells were cultured individually in varying(More)
OBJECTIVE To investigate tenocyte regulatory events during the development of overuse supraspinatus tendinosis in rats. METHODS Supraspinatus tendinosis was induced by running rats downhill at 1 km/hour for 1 hour a day. Tendons were harvested at 4, 8, 12, and 16 weeks and processed for brightfield, polarized light, or transmission electron microscopy.(More)
The stability of RNA, particularly mRNA, in tissues is under complex regulation. Most studies to date have focused on very cellular tissues and not connective tissues such as ligaments, tendons and cartilage. As the availability of such tissues for transplantation or research purposes is frequently delayed following death, it is important to determine(More)
PURPOSE Injuries to tendons, particularly flexor tendons, can lead to loss of function after healing due to adhesion formation and other complications. The aim of this study was to increase our understanding of the healing process in tendons and tendon sheaths to develop methods to affect the healing process and improve the outcome of tendon repair in the(More)