Australasian Radiation Research Articles

Phylogenetic Relationships Among Quolls Revisited: The mtDNA Control Region as a Useful Tool

There has been a great deal of interest in determining phylogenetic relationships within the family Dasyuridae due to the widespread distribution, ecological diversity, and relative plesiomorphy of this taxon within the Australasian marsupial radiation. In the past, it has been extremely problematic to determine the phylogenetic relationships among species within Dasyurus, with numerous studies using both morphological and molecular characters providing different topologies. Here, the mitochondrial DNA (mtDNA) control region is used as a novel set of characters in an attempt to identify relationships among the six closely related extant species. Sequences were obtained from multiple individuals representing all extant species of quolls including, when possible, individuals from different geographical regions. Sequences were analyzed using both parsimony criteria and neighbor-joining methods. Results presented here concur with those of Krajewski et al. (1997) in (1) placing D. geoffroii in a highly supported clade with D. spartacus, (2) resolving a monophyletic group of D. albopunctatus + D. geoffroii + D. spartacus, and (3) placing D. hallucatus as the sister taxon to all other species of quolls. Results also show two highly supported and geographically distinct clades of D. maculatus (Tasmanian and mainland) that do not correspond to the currently used subspecific nomenclature. Preliminary results also indicate that there are different clades among geographic groups of D. hallucatus that warrant further investigation. The mtDNA control region is a highly variable locus and may be used in forensic tests for species identification in this genus.

Relationships of some mannikins and waxbills in the estrildidae

There is disagreement as to the number of genera comprising the mannikins (Lonchurinae). Some authors recognize two to five of the following genera:Lonchura, Euodice, Padda, Spermestes andOdontospiza. Other authors have merged the last four taxa into the enlarged genusLonchura. We bring together data from downy plumes (neossoptiles), nestling palate markings, begging vocalizations, agonistic behaviour, courtship postures and starch gel electrophoresis of allozymes to solve these taxonomic problems. PAUP analysis of the combined data set indicates thatSpermestes andOdontospiza belong to a monophyletic clade separate fromEuodice, Padda andLonchura. We propose mergingOdontospiza withSpermestes, which suggests an African radiation of the group, and placing the generaPadda andEuodice in withLonchura, which represents a mostly Australasian radiation. The genusAmadina has been treated by some as a mannikin (Lonchurinae) and by others as a waxbill (Estrildinae). Our data indicate thatAmadina should be assigned to the estrildines rather than the lonchurines.Amadina's relatively large, mannikin-like conical bill is a result of convergence, probably reflecting selection pressure on bill shape associated with diet specializations.

Breast cancer following treatment for Hodgkin's disease: the need for screening in a young population. Australasian Radiation Oncology Lymphoma Group (AROLG)

Several recent publications have highlighted the issue of an increased risk of breast cancer in women treated with radiotherapy, chemotherapy, or combined modality therapy for Hodgkin's disease. The risk is greatest in women 30 years or younger at the time of treatment. In the Australasian Radiation Oncology Lymphoma Group database, 60% of women fell into this age category. This article reviews the available data pertaining to induction of breast cancer by radiotherapy for Hodgkin's disease. Breast examination should now be an integral part of the long term follow up for these women. There is also a case for the use of screening mammography. Any breast mass developing subsequent to treatment for Hodgkin's disease should be regarded with a high index of clinical suspicion and, accordingly, biopsies should be performed in the majority of cases, even when mammography is negative.

The use of simulator and CT information in the planning of radiotherapy for non-small cell lung cancer: An Australasian patterns of practice study

In a patterns of practice study 14 Australasian radiation oncologists were invited to define tumour and target volumes in 12 sample cases of non-small cell carcinoma of the lung (NSCCL) firstly using orthogonal simulator AP and lateral radiographic views, then using computed tomography (CT) slices obtained in the treatment position. In addition, they were asked to complete questionnaires addressing their criteria for determining treatment policy and their reasons for choosing specific tumour and target volume boundaries in individual cases. Significant variations in choice of size and position of both tumour and target volume were apparent between clinicians. These variations, however were no greater for simulator planned volumes than for CT planned volumes, except in cases selected for palliative treatment, were CT planned volumes were significantly larger. Failure to include tumour extensions, the mistaken inclusion of normal structures as tumour, and major differences in allowance for microscopic tumour spread were identified as the most significant cause for variation in the size and positioning of target volumes between clinicians. Differences over margins to allow for factors such as variation in day-to-day set-up, patient movement, equipment-related factors, etc, were also apparent. CT and simulator planned target volumes were equally successful in adequate tumour coverage; 79 162 (49%), and 80 162 (49%) respectively. Gross miss of tumour was more common in simulator planned target volumes than CT planned target volumes; 70 162 (43%) and 55 162 (34%), respectively. This study supports the integration of diagnostic expertise into the planning process for simulator and CT planning, but suggests that substantial practice variation would still exist in planning for radiotherapy in NSCCL.