title: The evaluation of processed cancellous bovine bone as a bone graft substitute

authors: Worth, Andrew J.

subjects: biomaterials

abstract: Objective: To determine the ability of a novel bovine cancellous bone xenoimplant to act as an osteoconductive graft in an ovine femoral defect model. An autograft harvested from the xenoimplant site was placed in a contralateral limb defect for comparison.
Material and methods: The xenoimplant used had been rendered immunologically inert by a novel defatting and deproteinating process. Following surgical implantation of cores into condylar cancellous bone defects, fluorochrome labels were administered to 12 sheep at 2 1/2, 4 1/2 and 8 weeks. Incorporation of the xenoimplants and autografts into the host bone was compared radiographically and histomorphometrically at 10 weeks.
Results: Radiographically, the degree of osteointegration was comparable. Histomorphometric data, consisting of labelled surface (LS) estimates, confirmed osteoconductive properties of both the xenoimplants and autografts. Remodelling activity was greatest in the xenoimplants at 2 1/2, weeks. At 4 1/2 weeks, there was more activity in the autograft, but by 8 weeks they were performing similarly. Xenoimplant-LS estimates were comparable or greater than those of the autograft at all times.
Conclusions: Processed bovine cancellous bone xenoimplants were osteoconductive in this model and show promise for development as a biomaterial in human and veterinary orthopaedic surgery.

text: The evaluation of processed cancellous bovine bone as a bone graft substitute Objective: To determine the ability of a novel bovine cancellous bone xenoimplant to act as an osteoconductive graft in an ovine femoral defect model. An autograft harvested from the xenoimplant site was placed in a contralateral limb defect for comparison.
Material and methods: The xenoimplant used had been rendered immunologically inert by a novel defatting and deproteinating process. Following surgical implantation of cores into condylar cancellous bone defects, fluorochrome labels were administered to 12 sheep at 2 1/2, 4 1/2 and 8 weeks. Incorporation of the xenoimplants and autografts into the host bone was compared radiographically and histomorphometrically at 10 weeks.
Results: Radiographically, the degree of osteointegration was comparable. Histomorphometric data, consisting of labelled surface (LS) estimates, confirmed osteoconductive properties of both the xenoimplants and autografts. Remodelling activity was greatest in the xenoimplants at 2 1/2, weeks. At 4 1/2 weeks, there was more activity in the autograft, but by 8 weeks they were performing similarly. Xenoimplant-LS estimates were comparable or greater than those of the autograft at all times.
Conclusions: Processed bovine cancellous bone xenoimplants were osteoconductive in this model and show promise for development as a biomaterial in human and veterinary orthopaedic surgery.

year: 2005

title: Acoustic and radio-transmitter retention in common carp (Cyprinus carpio) in New Zealand

authors: Daniel, Adam Joshua

subjects: surgical implant

abstract: Common carp (Cyprinus carpio) are notoriously difficult to monitor in water temperatures above 20◦C using telemetry owing to transmitter expulsion. To reduce transmitter loss, radio transmitters were anchored to the pelvic girdle and a polymer coating was applied to acoustic transmitters to reduce tissue irritation in two tank trials. Ten dummy transmitters were surgically implanted in each of four groups of adult koi carp, a highly coloured strain of C. carpio. Water temperatures ranged between 7 and 24◦C. After 365 days, the control and test groups of each trial had similar expulsion rates (P≥0.30; two-tailed Fisher’s exact probability test). Expulsion rates for uncoated acoustic transmitters were 60% (n=6), coated acoustic transmitters 50% (n=5), unanchored radio transmitters 60% (n=6) and anchored radio transmitters 90% (n=9). Expulsions occurred 15–362 days after implantation as a result of ulcers at or near the surgical wound. Bacterial infection of the wound appears to be the primary mechanism for transmitter expulsion.

text: Acoustic and radio-transmitter retention in common carp (Cyprinus carpio) in New Zealand Common carp (Cyprinus carpio) are notoriously difficult to monitor in water temperatures above 20◦C using telemetry owing to transmitter expulsion. To reduce transmitter loss, radio transmitters were anchored to the pelvic girdle and a polymer coating was applied to acoustic transmitters to reduce tissue irritation in two tank trials. Ten dummy transmitters were surgically implanted in each of four groups of adult koi carp, a highly coloured strain of C. carpio. Water temperatures ranged between 7 and 24◦C. After 365 days, the control and test groups of each trial had similar expulsion rates (P≥0.30; two-tailed Fisher’s exact probability test). Expulsion rates for uncoated acoustic transmitters were 60% (n=6), coated acoustic transmitters 50% (n=5), unanchored radio transmitters 60% (n=6) and anchored radio transmitters 90% (n=9). Expulsions occurred 15–362 days after implantation as a result of ulcers at or near the surgical wound. Bacterial infection of the wound appears to be the primary mechanism for transmitter expulsion.

year: 2009

title: Governance and legitimacy: Indigenous development in Aotearoa

authors: Dodd, Materoa

subjects: Māori governance

abstract: Within the indigenous paradigm lies a paradox over what constitutes legitimate Māori authority: Iwi structures are legitimated and recognised by the state, and traditional forms (for example, Hapū and Māori women), have had their authority diminished. Iwi authorities are colonial constructs that diminish the rights of Hapū and Māori women. The manner in which such constructs have come about generally has not involved tribewide debate over important issues in which Hapū and Māori women have an interest. For their legitimacy, emergent self-governing structures will need to be grounded in principles that ensure legitimate representation of Māori people and not socially constructed hybrids of a colonial past. Structures need to recognise Hapū and Māori women in the formulation, anything less than this will trigger a legitimation crisis.

text: Governance and legitimacy: Indigenous development in Aotearoa Within the indigenous paradigm lies a paradox over what constitutes legitimate Māori authority: Iwi structures are legitimated and recognised by the state, and traditional forms (for example, Hapū and Māori women), have had their authority diminished. Iwi authorities are colonial constructs that diminish the rights of Hapū and Māori women. The manner in which such constructs have come about generally has not involved tribewide debate over important issues in which Hapū and Māori women have an interest. For their legitimacy, emergent self-governing structures will need to be grounded in principles that ensure legitimate representation of Māori people and not socially constructed hybrids of a colonial past. Structures need to recognise Hapū and Māori women in the formulation, anything less than this will trigger a legitimation crisis.

year: 2000-10