Subchondral insufficiency fracture of the femoral head: a differential diagnosis in acute onset of coxarthrosis in the elderly.
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OBJECTIVE: To document subchondral insufficiency fracture (SIF) of the femoral head and investigate its frequency. METHODS: The study was based on a retrospective review of 464 removed femoral heads (from 419 patients) with both radiologic and histologic evidence of subchondral collapse. Gross photographs, specimen radiographs, and histologic sections were reevaluated in all cases. Available clinical notes and imaging studies were also reviewed. RESULTS: Ten cases previously diagnosed as osteonecrosis were reinterpreted as SIF on a histopathologic basis. All of these patients were women over 65 years old (average age 75) with osteopenia. The initial symptom was acute onset of hip pain. Radiologically, a subchondral collapse, mainly in the superolateral segment of the femoral head, was noted. Magnetic resonance imaging, available in 3 cases, showed diffuse low intensity on T1-weighted images and high intensity on T2-weighted or fat-suppressed images. Bone scintigraphy, available in 4 cases, showed increased uptake in the femoral head. Histopathologically, a 1.0-2.5-cm long linear whitish gray zone, comprising fracture callus and granulation tissue, was found beneath the subchondral bone end plate. There was no evidence of antecedent osteonecrosis. CONCLUSION: The results of this study indicate that SIF should be included in the differential diagnosis of acute onset of coxarthrosis in the elderly. (+info)
Delayed wound healing in the absence of intercellular adhesion molecule-1 or L-selectin expression.
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Inflammatory cells play a crucial role in wound healing, but the role of adhesion molecules including L-selectin and intercellular adhesion molecule-1 (ICAM-1) is not known in this process. We examined skin wound repair of excisional wounds in mice lacking L-selectin, ICAM-1, or both. The loss of ICAM-1 inhibited wound healing, keratinocyte migration from the edges of the wound toward the center, and granulation tissue formation. By contrast, L-selectin deficiency alone did not affect any of these parameters. However, the loss of both L-selectin and ICAM-1 resulted in inhibition of keratinocyte migration and granulation tissue formation beyond those caused by loss of ICAM-1 alone. Treatment of platelet-derived growth factor to the wounds normalized delayed wound healing in ICAM-1(-/-) mice, but not in L-selectin/ICAM-1(-/-) mice. Therefore, although ICAM-1 contributes to wound repair to a greater extent than L-selectin, a role for L-selectin was revealed in the absence of ICAM-1. The impaired wound repair was associated with reduced infiltration of neutrophils and macrophages in ICAM-1(-/-) and L-selectin/ICAM-1(-/-) mice. These results demonstrate a distinct role of ICAM-1 and L-selectin in wound healing and that the delayed wound healing in the absence of these molecules is likely because of decreased leukocyte accumulation into the wound site. (+info)
Thrombospondin-1 suppresses wound healing and granulation tissue formation in the skin of transgenic mice.
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The function of the endogenous angiogenesis inhibitor thrombospondin-1 (TSP-1) in tissue repair has remained controversial. We established transgenic mice with targeted overexpression of TSP-1 in the skin, using a keratin 14 expression cassette. TSP-1 transgenic mice were healthy and fertile, and did not show any major abnormalities of normal skin vascularity, cutaneous vascular architecture, or microvascular permeability. However, healing of full-thickness skin wounds was greatly delayed in TSP-1 transgenic mice and was associated with reduced granulation tissue formation and highly diminished wound angiogenesis. Moreover, TSP-1 potently inhibited fibroblast migration in vivo and in vitro. These findings demonstrate that TSP-1 preferentially interfered with wound healing-associated angiogenesis, rather than with the angiogenesis associated with normal development and skin homeostasis, and suggest that therapeutic application of angiogenesis inhibitors might potentially be associated with impaired wound vascularization and tissue repair. (+info)
Spinal tuberculosis in HIV positive and negative patients: immunological response and clinical outcome.
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We measured cytokine secretion patterns in peripheral blood and granulation tissue by flow cytometry in 16 human immunodeficiency virus (HIV) positive and 26 HIV negative patients with spinal tuberculosis. Anti-retroviral therapy was not prescribed. There were no significant differences in the postoperative morbidity and neurological recovery between the two groups. (+info)
Early reactions after reimplantation of the tendon of supraspinatus into bone. A study in rabbits.
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In 14 rabbits we determined the origin of the cells effecting healing of the tendon of supraspinatus inserted into a bony trough. After two weeks both the cellularity of the underlying bone and the thickness of the subacromial bursa were significantly increased in the operated compared with the control shoulders. The cellularity of the stump of the tendon, however, was significantly decreased in the operated shoulders. In this model, both the underlying bone and the subacromial bursa but not the stump of the tendon contributed to the process of repair. We conclude that the medial stump should be debrided judiciously but that cutting back to bleeding tissue is not necessary during repair of the rotator cuff. Moreover, great care should be taken to preserve the subacromial bursa since it seems to play an important role in the healing process. (+info)
Cyclooxygenase-2-mediated angiogenesis in carrageenin-induced granulation tissue in rats.
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The possible participation of cyclooxygenase (COX)-2 in angiogenesis in granulation tissue was analyzed using an air pouch-type carrageenin-induced inflammation model in rats. Injection of carrageenin solution into an air pouch induced gradual increases in the pouch fluid volume and granulation tissue weight as well as angiogenesis in granulation tissue. NS-398 (10-100 microg) inhibited all of these parameters in a dose-dependent manner. NS-398 (100 microg), indomethacin (100 microg), and dexamethasone (10 microg) markedly reduced prostaglandin (PG) E(2) levels in the pouch fluid at day 6. NS-398 and indomethacin did not affect protein levels of COX-1 and COX-2 but dexamethasone significantly reduced the level of COX-2 in granulation tissue at day 6. Protein levels of vascular endothelial growth factor (VEGF) in granulation tissue and in the pouch fluid were higher at day 6 than at day 3, and the levels were decreased by treatment with NS-398 (10-100 microg) in a dose-dependent manner. The inhibitory effects of NS-398 (100 microg) were almost the same as those of indomethacin (100 microg). Dexamethasone (10 microg) also reduced VEGF protein levels in granulation tissue at day 6. To clarify the role of PGE(2) in VEGF production, minced granulation tissue obtained 3 days after carrageenin injection from the indomethacin-treated rats was incubated in the presence of various concentrations of PGE(2). It was shown that VEGF mRNA and protein levels in the minced granulation tissue were increased by PGE(2) in a concentration-dependent manner. These findings suggest that COX-2-derived PGE(2) plays a significant role in angiogenesis in the carrageenin-induced granulation tissue through VEGF formation. (+info)
Endothelial cells of hematopoietic origin make a significant contribution to adult blood vessel formation.
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Granulation tissue formation is an example of new tissue development in an adult. Its rich vascular network has been thought to derive via angiogenic sprouting and extension of preexisting vessels from the surrounding tissue. The possibility that circulating cells of hematopoietic origin can differentiate into vascular endothelial cells (ECs) in areas of vascular remodeling has recently gained credibility. However, no quantitative data have placed the magnitude of this contribution into a physiological perspective. We have used hematopoietic chimeras to determine that 0.2% to 1.4% of ECs in vessels in control tissues derived from hematopoietic progenitors during the 4 months after irradiation and hematopoietic recovery. By contrast, 8.3% to 11.2% of ECs in vessels that developed in sponge-induced granulation tissue during 1 month derived from circulating hematopoietic progenitors. This recruitment of circulating progenitors to newly forming vessels would be difficult to observe in standard histological studies, but it is large enough to be encouraging for attempts to manipulate this contribution for therapeutic gain. (+info)
Physeal dysplasia with slipped capital femoral epiphysis in 13 cats.
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Separation of the femoral capital epiphysis is associated with severe trauma in most species. This report describes 13 cats with slipped capital femoral epiphysis characterized by a distinctive lesion in the physeal cartilage. The lesion consists of irregular clusters of chondrocytes separated by abundant matrix on both the epiphyseal and metaphyseal side of the cleavage site. The affected population in this study is 85% male, 90% overweight, 23% Siamese, and 4.5-24 months old. The histopathology and demographics are similar to slipped capital femoral epiphysis in humans, which most often affects overweight adolescent boys. (+info)