125 research outputs found
Use of mesenchymal stem cells to enhance bone formation around revision hip replacements
No full textMichelle Korda, Gordon Blunn, Allen Goodship and Jia Hu
Technique for enhancing signal in conventional backscattering fluorescence and Raman spectroscopy of turbid media
No full textCopyright © 2008 American Chemical SocietyKevin Buckley, Allen Goodship, Neil A. Macleod, Anthony W. Parker, and Pavel Matouse
Aspartic acid racemization and collagen degradation markers reveal an accumulation of damage in tendon collagen that is enhanced with aging
No full textChavaunne T. Thorpe, Ian Streeter, Gina L. Pinchbeck, Allen E. Goodship, Peter D. Clegg and Helen L. Birc
Prevention of strain-related osteopenia in aseptic loosening of hip prostheses using perioperative bisphosphonate
No full text© 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:693-703, 2008Allen E. Goodship, Gordon W. Blunn, Jonathan Green and Melanie J. Coathu
Prediction of sublayer depth in turbid media using spatially offset Raman spectroscopy
No full textCopyright © 2008 American Chemical SocietyN. A. Macleod, A. Goodship, A. W. Parker and P. Matouse
The scale-up of a tissue engineered porous hydroxyapatite polymer composite scaffold for use in bone repair: an ovine femoral condyle defect study
No full textThe development of an osteogenic bone graft substitute has important practical and cost implications in many branches of medicine where bone regeneration is required. Previous in vitro and small animal (murine) in vivo studies highlighted a porous hydroxyapatite/poly (dl‐lactic acid) composite scaffold in combination with skeletal stem cells (SSCs) as a potential bone graft substitute candidate. The aim of the current study was to scale up the bone cell‐scaffold construct to large animals and examine the potential for repair of a critical‐sized defect via an ovine model. SSC seeded scaffolds (and unseeded scaffold controls) were implanted bilaterally into ovine femoral condyle critical defects for 3 months. A parallel in vitro analysis of ovine SSC seeded scaffolds was also performed. Post mortem mechanical indentation testing showed the bone strengths of the defect sites were 20% (controls) and 11% (SSC seeded scaffolds) those of normal cancellous bone (p < 0.01). MicroCT analysis demonstrated new bone formation within all defects with a mean increase of 13.4% in the control scaffolds over the SSC seeded scaffolds (p = 0.14). Histological examination confirmed these findings, with enhanced quality new bone within the control defects. This study highlights important issues and steps to overcome in scale‐up and translation of tissue engineered products. The scaffold demonstrated encouraging results as an osteoconductive matrix; however, further work is required with cellular protocols before any human trials
The effect of early training and the adaptation and conditioning of skeletal tissues
No full textRoger K.W. Smith and Allen E. Goodshi
Large animal in vivo evaluation of a binary blend polymer scaffold for skeletal tissue-engineering strategies: translational issues
No full textBinary blend polymers offer the opportunity to combine different desirable properties into a single scaffold, to enhance function within the field of tissue engineering. Previous in vitro and murine in vivo analysis identified a polymer blend of poly(l‐lactic acid)–poly(ε‐caprolactone) (PLLA:PCL 20:80) to have characteristics desirable for bone regeneration. Polymer scaffolds in combination with marrow‐derived skeletal stem cells (SSCs) were implanted into mid‐shaft ovine 3.5 cm tibial defects, and indices of bone regeneration were compared to groups implanted with scaffolds alone and with empty defects after 12 weeks, including micro‐CT, mechanical testing and histological analysis. The critical nature of the defect was confirmed via all modalities. Both the scaffold and scaffold/SSC groups showed enhanced quantitative bone regeneration; however, this was only found to be significant in the scaffold/SSCs group (p = 0.04) and complete defect bridging was not achieved in any group. The mechanical strength was significantly less than that of contralateral control tibiae (p < 0.01) and would not be appropriate for full functional loading in a clinical setting. This study explored the hypothesis that cell therapy would enhance bone formation in a critical‐sized defect compared to scaffold alone, using an external fixation construct, to bridge the scale‐up gap between small animal studies and potential clinical translation. The model has proved a successful critical defect and analytical techniques have been found to be both valid and reproducible. Further work is required with both scaffold production techniques and cellular protocols in order to successfully scale‐up this stem cell/binary blend polymer scaffold
of a collagenase-induced tendon injury to treatment with a polysulphated glycosaminoglycan (Adequan)
No full textThis study explored the hypothesis that local administration of a polysulphated glycosaminoglycan (PSGAG) in the early phase of healing of a standard collagenase-induced tendon injury in the superficial digital flexor tendon of the rabbit would reduce the degenerative effects of inflammatory mediators and proteases and preserve normal tendon morphology, composition, and biomechanical properties. Histological and ultrastructural changes together with the mechanical properties, dry weight, collagen content, and amount of DNA in healing tissue at the site of the lesion were assessed in treated and untreated animals. In treated lesions 28 days after injury, the normal orientation of tenoblasts and collagen fibrils was well preserved compared with the disorganized scar formation seen in untreated animals. The degree of cellularity was significantly higher in the untreated lesions. At the ultrastructural level the collagen in the healing tissue of the treated animals consisted of a mixture of small diameter, new regenerated fibrils intermingled with well-preserved large diameter, old fibrils, aligned to the long axis of the tendon; in untreated animals small, randomly arranged new fibrils predominated. The diameters of treated tendons had returned to normal, but in untreated animals the injured tendons remained significantly thicker than their controls. The percentage dry weight and collagen contents of treated injured tendons approximated those of control normal tendons, whereas those of untreated tendons were significantly less than those of the control values. The DNA content of injured treated tendons was not significantly different from that of normal contralateral controls, while in the untreated tendons it was significantly higher. There were no significant differences between the normal and the contralateral treated injured tendons in ultimate strength, fatigue strength, stiffness, and maximum absorbed energy. However in the untreated animals, although the tendon diameter was significantly greater, the ultimate strength, fatigue strength, stiffness, and maximum absorbed energy were significantly lower than the contralateral control. These data suggest that polysulphated glycosaminoglycans are effective in restoring the morphological, biochemical, and biomechanical properties of injured soft connective tissues and may be of clinical value in the treatment of acute tendon injury.Ahmad Oryan, Allen E. Goodship and Ian A. Silve
Polar bears (Ursus maritimus), the most evolutionary advanced hibernators, avoid significant bone loss during hibernation
No full textSome hibernating animals are known to reduce muscle and bone loss associated with mechanical unloading during prolonged immobilisation, compared to humans. However, here we show that wild pregnant polar bears (Ursus maritimus) are the first known animals to avoid significant bone loss altogether, despite six months of continuous hibernation. Using serum biochemical markers of bone turnover, we showed that concentrations for bone resorption are not significantly increased as a consequence of hibernation in wild polar bears. This is in sharp contrast to previous studies on other hibernating species, where for example, black bears (Ursus americanus), show a 3–4 fold increase in serum bone resorption concentrations post-hibernation, and must compensate for this loss through rapid bone recovery on remobilisation, to avoid the risk of fracture. In further contrast to black bears, serum concentrations of bone formation markers were highly significantly increased in pregnant female polar bears compared to non-pregnant, thus non-hibernating females both prior to and after hibernation. However, bone formation concentrations in new mothers were significantly reduced compared to pre-hibernation concentrations. The de-coupling of bone turnover in favour of bone formation prior to hibernation, suggests that wild polar bears may posses a unique physiological mechanism for building bone in protective preparation against expected osteopenia associated with disuse, starvation, and hormonal drives to mobilise calcium for reproduction, during hibernation. Understanding this physiological mechanism could have profound implications for a natural solution for the prevention of osteoporosis in animals subjected to captivity with inadequate space for exercise, humans subjected to prolonged bed rest while recovering from illness, or astronauts exposed to antigravity during spaceflight.Alanda R. Lennox and Allen E. Goodshi
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