Long-term clinical and experimental/surface analytical studies of carbon/carbon maxillofacial implants

BACKGROUND:Over the past 30-40years, various carbon implant materials have become more interesting, because they are well accepted by the biological environment. The traditional carbon-based polymers give rise to many complications. The polymer complication may be eliminated through carbon fibres bound by pyrocarbon (carbon/carbon). The aim of this study is to present the long-term clinical results of carbon/carbon implants, and the results of the scanning electron microscope and energy dispersive spectrometer investigation of an implant retrieved from the human body after 8years.METHODS:Mandibular reconstruction (8-10years ago) was performed with pure (99.99%) carbon implants in 16 patients (10 malignant tumours, 4 large cystic lesions and 2 augmentative processes). The long-term effect of the human body on the carbon/carbon implant was investigated by comparing the structure, the surface morphology and the composition of an implant retrieved after 8years to a sterilized, but not implanted one.RESULTS:Of the 16 patients, the implants had to be removed earlier in 5 patients because of the defect that arose on the oral mucosa above the carbon plates. During the long-term follow-up, plate fracture, loosening of the screws, infection or inflammations around the carbon/carbon implants were not observed. The thickness of the carbon fibres constituting the implants did not change during the 8-year period, the surface of the implant retrieved was covered with a thin surface layer not present on the unimplanted implant. The composition of this layer is identical to the composition of the underlying carbon fibres. Residual soft tissue penetrating the bulk material between the carbon fibre bunches was found on the retrieved implant indicating the importance of the surface morphology in tissue growth and adhering implants.CONCLUSIONS:The surface morphology and the structure were not changed after 8years. The two main components of the implant retrieved from the human body are still carbon and oxygen, but the amount of oxygen is 3-4 times higher than on the surface of the reference implant, which can be attributed to the oxidative effect of the human body, consequently in the integration and biocompatibility of the implant. The clinical conclusion is that if the soft part cover is appropriate, the carbon implants are cosmetically and functionally more suitable than titanium plates

The tyrosine kinase inhibitor dasatinib (SPRYCEL) inhibits chondrocyte activity and proliferation

Letter to the EditorK Vandyke, S Fitter and ACW Zannettin

Mapping evolutionary process: a multi-taxa approach to conservation prioritization

Human-induced land use changes are causing extensive habitat fragmentation. As a result, many species are not able to shift their ranges in response to climate change and will likely need to adapt in situ to changing climate conditions. Consequently, a prudent strategy to maintain the ability of populations to adapt is to focus conservation efforts on areas where levels of intraspecific variation are high. By doing so, the potential for an evolutionary response to environmental change is maximized. Here, we use modeling approaches in conjunction with environmental variables to model species distributions and patterns of genetic and morphological variation in seven Ecuadorian amphibian, bird, and mammal species. We then used reserve selection software to prioritize areas for conservation based on intraspecific variation or species-level diversity. Reserves selected using species richness and complementarity showed little overlap with those based on genetic and morphological variation. Priority areas for intraspecific variation were mainly located along the slopes of the Andes and were largely concordant among species, but were not well represented in existing reserves. Our results imply that in order to maximize representation of intraspecific variation in reserves, genetic and morphological variation should be included in conservation prioritization

Embracing plurality through oral language

The transmission and dissemination of knowledge in Aboriginal societies for the most part occurs orally in an Aboriginal language or in Aboriginal English. However, whilst support is given to speaking skills in Indigenous communities, in our education system less emphasis is given to developing equivalent oral communicative competence in Standard Australian English (SAE). Instead the focus is given to the ongoing assessment of reading and writing skills and grammatical knowledge – this is in direct contrast to the existing language experience of Aboriginal students. Therefore, for Aboriginal students to participate in mainstream society, we suggest that there is a need to nurture oral language skills in SAE and provide learners with the experience to develop their code-switching ability to maintain continuity with their first language or dialect. Drawing on previous research that we and others have undertaken at several schools, this paper highlights the need for three fundamental changes to take place within language education: (1) school policies to change and explicitly accept and support Aboriginal English in code-switching situations; (2) familiarity among school staff about the major differences between Aboriginal English and SAE; and (3) tasks that focus on developing and practising the ‘when, why and how’ of code-switching

James K. Kieswetter interview

James Kieswetter was born in Dodge City, Kansas in 1942. Kieswetter earned his PhD from history from the University of Colorado and began teaching at Eastern Washington State College in 1968, where he taught military history among other subjects. At Eastern, he won the Trustees Medal in 1982, the Burlington Northern Faculty Achievement Award in 1986, and the Department of the Army Commander’s Award for Public Service in 2004. Kieswetter authored multiple books on French history including Etienne-Denis Pasquier, the Last Chancellor of France, Metternich and the Bourbon Succession, 1819-1820, and French Diplomacy at the Congresses of Troppau and Laibach. Kieswetter earned Emeritus status at Eastern in 2013