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2.
3.
J Orthop Res ; 2024 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-39182184

RESUMEN

Articular joints facilitate motion and transfer loads to underlying bone through a combination of cartilage tissue and synovial fluid, which together generate a low-friction contact surface. Traumatic injury delivered to cartilage and the surrounding joint capsule causes secretion of proinflammatory cytokines by chondrocytes and the synovium, triggering cartilage matrix breakdown and impairing the ability of synovial fluid to lubricate the joint. Once these inflammatory processes become chronic, posttraumatic osteoarthritis (PTOA) development begins. However, the exact mechanism by which negative alterations to synovial fluid leads to PTOA pathogenesis is not fully understood. We hypothesize that removing the lubricating macromolecules from synovial fluid alters the relationship between mechanical loads and subsequent chondrocyte behavior in injured cartilage. To test this hypothesis, we utilized an ex vivo model of PTOA that involves subjecting cartilage explants to a single rapid impact followed by continuous articulation within a lubricating bath of either healthy synovial fluid, phosphate-buffered saline (PBS), synovial fluid treated with hyaluronidase, or synovial fluid treated with trypsin. These treatments degrade the main macromolecules attributed with providing synovial fluid with its lubricating properties; hyaluronic acid and lubricin. Explants were then bisected and fluorescently stained to assess global and depth-dependent cell death, caspase activity, and mitochondrial depolarization. Explants were tested via confocal elastography to determine the local shear strain profile generated in each lubricant. These results show that degrading hyaluronic acid or lubricin in synovial fluid significantly increases middle zone chondrocyte damage and shear strain loading magnitudes, while also altering chondrocyte sensitivity to loading.

4.
J Am Vet Med Assoc ; 262(9): 1154-1159, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39032506
8.
J Am Vet Med Assoc ; 262(1): 9, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38103388
9.
Am J Vet Res ; 84(12)2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-38041952
12.
Am J Vet Res ; 84(10)2023 08 28.
Artículo en Inglés | MEDLINE | ID: mdl-37793640
13.
Am J Sports Med ; 51(12): 3288-3303, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37602735

RESUMEN

BACKGROUND: Current cartilage repair therapies do not re-create the complex mechanical interface between cartilage and bone, which is critical for long-term repair durability. New biomaterial designs that include hard tissue-soft tissue interface structures offer promise to improve clinical outcomes. PURPOSE/HYPOTHESIS: The purpose of this study was to evaluate the efficacy and safety of a naturally derived osteochondral biotemplate with a novel contiguous hard tissue-soft tissue interface in an ovine model as a regenerative solution for articular cartilage defects. It was hypothesized that the osteochondral biotemplate would produce structurally superior repair tissue compared with microfracture over a 13-month period. STUDY DESIGN: Controlled laboratory study. METHODS: Osteochondral biotemplates were manufactured from porcine cancellous bone. Skeletally mature sheep (N = 30) were randomly allocated to 3 groups: early healing stage (euthanasia at 4 months), 6-month treatment, and 13-month treatment. In the early healing stage group, an 8 mm-diameter by 5 mm-deep osteochondral defect was created on the medial femoral condyle and treated at the time of iatrogenic injury with an osteochondral biotemplate. The contralateral limb received the same treatment 2 months later. In the 6- and 13-month treatment groups, 1 limb received the same osteochondral procedure as the early healing stage group. In the contralateral limb, an 8 mm-diameter, full-thickness cartilage defect (1-2 mm deep) was created and treated with microfracture. Cartilage repair and integration were quantitatively and qualitatively assessed with gross inspection, histological evaluation, and magnetic resonance imaging (MRI). Wilcoxon signed-rank and McNemar tests were used to compare the treatments. RESULTS: At 6 and 13 months after treatment, the biotemplate was not present histologically. At 13 months, the biotemplate treatment demonstrated statistically higher histological scores than microfracture for integration with surrounding cartilage (biotemplate: 74 ± 31; microfracture: 28 ± 39; P = .03), type 2 collagen (biotemplate: 72 ± 33; microfracture: 40 ± 38; P = .02), total cartilage (biotemplate: 71 ± 9; microfracture: 59 ± 9; P = .01), and total integration (biotemplate: 85 ± 15; microfracture: 66 ± 20; P = .04). The osteochondral biotemplate treatment produced a notable transient nonneutrophilic inflammatory response that appeared to approach resolution at 13 months. MRI results were not statistically different between the 2 treatments. CONCLUSION: Even with the inflammatory response, after 13 months, the osteochondral biotemplate outperformed microfracture in cartilage regeneration and demonstrated superiority in integration between the repair tissue and host tissue as well as integration between the newly formed cartilage and the underlying bone. CLINICAL RELEVANCE: This work has demonstrated the clinical potential of a novel biomaterial template to regenerate the complex mechanical interface between cartilage and the subchondral bone.


Asunto(s)
Enfermedades de los Cartílagos , Cartílago Articular , Fracturas por Estrés , Fracturas Intraarticulares , Animales , Ovinos , Porcinos , Fracturas por Estrés/cirugía , Fracturas por Estrés/patología , Cartílago Articular/lesiones , Enfermedades de los Cartílagos/patología , Colágeno Tipo II , Fracturas Intraarticulares/patología , Materiales Biocompatibles
15.
Am J Vet Res ; 84(7)2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-37393068
16.
Vet Clin North Am Equine Pract ; 39(3): 453-459, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37442728

RESUMEN

Bone marrow concentrate is generated by centrifugation of bone marrow aspirate. It contains mesenchymal stromal cells, anabolic chemokines/cytokines, and supraphysiological concentrations of interleukin-1 receptor antagonist protein (IL-1RA). It is an effective treatment for osteoarthritis or desmitis, or as an adjunct in surgery to enhance bone or cartilage repair.


Asunto(s)
Enfermedades de los Caballos , Células Madre Mesenquimatosas , Osteoartritis , Animales , Caballos , Médula Ósea , Enfermedades de los Caballos/terapia , Enfermedades de los Caballos/metabolismo , Resultado del Tratamiento , Células Madre Mesenquimatosas/metabolismo , Osteoartritis/veterinaria
17.
J Am Vet Med Assoc ; 261(8): 1106-1107, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37481250
18.
J Am Vet Med Assoc ; 261(7): 949, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37330220
19.
J Am Vet Med Assoc ; 261(6): 785, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-37225150
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