Healing of displaced condylar process fracture in rats submitted to protein undernutrition

Introduction: This study evaluated the healing of mandibular condylar fracture in rats submitted to experimental and protein undernutrition (8% of protein) by means of histological analysis. Material: Forty-five adult Wistar rats were divided into three groups of 15 animals: a fracture group, who were submitted to condylar fracture with no changes in diet; an undernourished fracture group, who were submitted to a low protein diet and condylar fracture: an undernourished group, kept until the end of experiment, without condylar fracture. Displaced fractures of the right condyle were created under general anaesthesia. The histological study comprised fracture site and temporomandibular joint evaluations. Results: The undernourished fracture group showed significant weight loss. There was a marked decrease in the values of serum proteins and albumin in the undernourished fracture group. Histological analysis showed that protein undernutrition lead to atrophy of the condylar fibrocartilage. Fractures in undernutrition presented a delay in callus formation due to more extensive devitalized bone areas, and after 3 months there were still bone formation areas, while fibrous ankylosis occurred in the articular space. Conclusion: It was concluded that mandibular condyle fractures in rats with protein undernutrition had impaired callus formation, as well as fibrous ankylosis into the temporomandibular joint. (C) 2010 European Association for Cranio-Maxillo-Facial Surgery.

Beyond the middle: A report about literacy and numeracy development of target group students in the middle years of schooling: Volume 2 (Appendices)

This research project was commissioned by the Commonwealth Department of Education, Science and Training to investigate the perceived efficacy of middle years programs in all States and Territories in improving the quality of teaching, learning and student outcomes - especially in literacy and numeracy and for student members of particular target groups. The latter groups included students from lower socio-economic communities, Aboriginal and Torres Strait Islander (Indigenous) communities, students with a Language Background Other than English (hereafter LBOTE), rural and remote students, and students struggling with the transition from middle/upper primary to the junior secondary years.

Influence of Osteopenia in Autogenous Bone Graft Healing With or Without Expanded Polytetrafluoroethylene Membranes: Histologic and Histomorphometric Study in Rats

Purpose: The aim of this study was to quantitatively evaluate and qualitatively describe autogenous bone graft healing with or without an expanded polytetrafluoroethylene (e-PTFE) membrane in ovariectornized rats. Materials and Methods: Eighty Wistar rats, weighing approximately 300 g each, were used. A graft was obtained from the parietal bone and fixed to the sidewall of each animal`s left mandibular ramus. The animals were randomly divided into four experimental groups (n = 20 in each group): group 1, sham operated and autogenous bone graft only- group 2, sham operated and autogenous bone graft covered by e-PTFE membrane; group 3, ovariectornized (OVX) and autogenous bone graft only- group 4, OVX and autogenous bone graft covered by e-PTFE membrane. The animals were sacrificed at five different time points: immediately after grafting or at 7, 21, 45, or 60 days after grafting. Histologic examination and morphometric measurement of the sections were performed, and values were submitted to statistical analyses. Results: Both groups (sham and OVX) experienced loss of the original graft volume when it was not covered by the membrane, whereas use of the membrane resulted in additional bone formation beyond the edges of the graft and under the membrane. Histologic analysis showed integration of the grafts in all animals, although a larger number of marrow spaces was found in OVX groups. Conclusions: Association of bone graft with an e-PTFE membrane resulted in maintenance of its original volume as well as formation of new bone that filled the space under the membrane. Osteopenia did not influence bone graft repair, regardless of whether or not it was associated with e-PTFE membrane, but descriptive histologic analysis showed larger numbers of marrow spaces in the bone graft and receptor bed and formation of new bone in the OVX animals. INT J ORAL MAXILLOFAC IMPLANTS 2009;24:1074-1082

Healing of critical-size cranial defects in guinea pigs using a bovine bone-derived resorbable membrane

Purpose: To investigate the healing of critical-size cranial bone defects (9-mm-diameter) in guinea pigs treated with a bovine bone-derived resorbable membrane. Materials and Methods: A sample of 42 guinea pigs was divided into test (n = 20), control (n = 20), and standard (n = 2) groups. A full-thickness trephine defect was made in the fronto-parietal bone of each animal. In the test group, the internal and external openings of the defect were each closed with a separate membrane, and the space between them was filled with blood clot and a central spacer. In the control group, the defect was filled only with the blood clot and spacer. At 1, 3, 6, and 9 months later, the calvarias (5 per period) for both the test and control groups were collected, fixed, radiographed, and histologically processed. The Standard-group animals were sacrificed immediately after surgery and used to determine the initial size of defect radiographically. The areas of defects in the radiographs were measured with image-analysis software and were compared between groups and periods by multiple regression analysis with the Bonferroni correction. Results: At 1 and 3 months, newly formed woven bone was histologically observed in both test and control groups. Radiographically, this new bone occupied an average of 32% of the defect area at 1 month and 60% at 3 months in the test group. In the control group, 21% of the defect was filled at 1 month and 39% at 3 months. However, the differences between treatments were not statistically significant (P > .05). At 6 and 9 months, a significant increase in newly formed lamellar bone was seen histologically in both groups. Radiographically, for the test group, the new bone occupied an average of 82% of the defect area at 6 months and 96% at 9 months. For the control group, new bone composed an average of 45% of the defect area at 6 months and 40% at 9 months. The differences between the test and control groups were statistically significant at 6 and 9 months (P < .05). Complete or almost complete filling of the defect was observed in several cases. Conclusion: It was concluded that the bovine bone-derived membrane is highly biocompatible and is able to promote good healing of critical-size defects in calvaria of guinea pig.

Modelling basin level allocation of water in the Murray-Darling Basin in a world of uncertainty, Murray-Darling Program Working Papers WPM05-1, Risk and Sustainable Management Group, 8 February 2005

Abstract: The Murray-Darling Basin comprises over 1 million km2; it lies within four states and one territory; and over 12, 800 GL of irrigation water is used to produce over 40% of the nation's gross value of agricultural production. This production is used by a diverse collection of some-times mutually exclusive commodities (e.g. pasture; stone fruit; grapes; cotton and field crops). The supply of water for irrigation is subject to climatic and policy uncertainty. Variable inflows mean that water property rights do not provide a guaranteed supply. With increasing public scrutiny and environmental issues facing irrigators, greater pressure is being placed on this finite resource. The uncertainty of the water supply, water quality (salinity), combined with where water is utilised, while attempting to maximising return for investment makes for an interesting research field. The utilisation and comparison of a GAMS and Excel based modelling approach has been used to ask: where should we allocate water?; amongst what commodities?; and how does this affect both the quantity of water and the quality of water along the Murray-Darling river system?