A preliminary investigation of parenting attributes of Australian foster carers

Utilising a comparison research design of mothers involved in fostering (N= 28) and their peers (N =28), the major findings were that within the fostering group, those who had been fostering the longest had the lowest sense of efficacy, reflecting that the experience of providing foster care eroded parents' sense of their own skill. In terms of attachment to the children, the data suggested that foster carers may resist becoming too close to the children in their care in order to limit the emotional cost of subsequent separation. Importantly, there was no significant correlation between the length of time in providing foster care and marital satisfaction, which supports the notion that providing foster care does not, in itself cause marital stress. While formal support services were more utilised by foster carers there was some indication that this group is not well integrated into the broader community. Collectively, these findings demonstrate that over the long- term providing fostering care has some negative consequences for the carers in terms of their self-confidence. Agencies designated to work with carers need to consider proactive strategies to reduce this consequence.

Determination of Wolbachia genome size by Pulsed-Field Gel Electrophoresis

Genome sizes of six different Wolbachia strains from insect and nematode hosts have been determined by pulsed-field gel electrophoresis of purified DNA both before and after digestion with rare-cutting restriction endonucleases. Enzymes SmaI, ApaI, AscI, and FseI cleaved the studied Wolbachia strains at a small number of sites and were used for the determination of the genome sizes of wMelPop, wMel, and wMelCS (each 1.36 Mb), wRi (1.66 Mb), wBma (1.1 Mb), and wDim (0.95 Mb). The Wolbachia genomes studied were all much smaller than the genomes of free-living bacteria such as Escherichia coli (4.7 Mb), as is typical for obligate intracellular bacteria. There was considerable genome size variability among Wolbachia strains, especially between the more parasitic A group Wolbachia infections of insects and the mutualistic C and D group infections of nematodes. The studies described here found no evidence for extrachromosomal plasmid DNA in any of the strains examined. They also indicated that the Wolbachia genome is circular.

Referral to post-acute care following traumatic brain injury (TBI) in the Australian context

The study aimed to describe the types of care allocated at the end of acute care to people diagnosed with TBI and to identify the factors associated with variations in referral to care. A retrospective analysis of medical records of 61 patients was conducted based on a sample from two hospitals. While 60.7% of the study sample were referred to formal rehabilitation care, this was primarily non-inpatient rehabilitation care (32.8%). Discriminant analysis was used to determine medical and non-medical predictors of referral. Results indicated that place of treatment and age contribute to group differences and were significant in separating the inpatient rehabilitation group from the non-inpatient and no rehabilitation groups. Review by a rehabilitation physician was associated with referral to inpatient rehabilitation but was not adequate to explain referral to non-inpatient rehabilitation. An in-depth exploration of post-acute referral is warranted to improve policy and practice in relation to continuity of care following TBI.

Experimental methods for studying drug uptake in the head and brain

A number of techniques have been developed to study the disposition of drugs in the head and, in particular, the role of the blood-brain barrier (BBB) in drug uptake. The techniques can be divided into three groups: in-vitro, in-vivo and in-situ. The most suitable method depends on the purpose(s) and requirements of the particular study being conducted. In-vitro techniques involve the isolation of cerebral endothelial cells so that direct investigations of these cells can be carried out. The most recent preparations are able to maintain structural and functional characteristics of the BBB by simultaneously culturing endothelial cells with astrocytic cells,The main advantages of the in-vitro methods are the elimination of anaesthetics and surgery. In-vivo methods consist of a diverse range of techniques and include the traditional Brain Uptake Index and indicator diffusion methods, as well as microdialysis and positron emission tomography. In-vivo methods maintain the cells and vasculature of an organ in their normal physiological states and anatomical position within the animal. However, the shortcomings include renal acid hepatic elimination of solutes as well as the inability to control blood flow. In-situ techniques, including the perfused head, are more technically demanding. However, these models have the ability to vary the composition and flow rate of the artificial perfusate. This review is intended as a guide for selecting the most appropriate method for studying drug uptake in the brain.

Genetic covariance between indices of body condition and immunocompetence in a passerine bird

Background: Condition-dependence is a ubiquitous feature of animal life histories and has important implications for both natural and sexual selection. Mate choice, for instance, is typically based on condition-dependent signals. Theory predicts that one reason why condition-dependent signals may be special is that they allow females to scan for genes that confer high parasite resistance. Such explanations require a genetic link between immunocompetence and body condition, but existing evidence is limited to phenotypic associations. It remains unknown, therefore, whether females selecting males with good body condition simply obtain a healthy mate, or if they acquire genes for their offspring that confer high immunocompetence. Results: Here we use a cross-foster experimental design to partition the phenotypic covariance in indices of body condition and immunocompetence into genetic, maternal and environmental effects in a passerine bird, the zebra finch Taeniopygia guttata. We show that there is significant positive additive genetic covariance between an index of body condition and an index of cell-mediated immune response. In this case, genetic variance in the index of immune response explained 56% of the additive genetic variance in the index of body condition. Conclusion: Our results suggest that, in the context of sexual selection, females that assess males on the basis of condition-dependent signals may gain genes that confer high immunocompetence for their offspring. More generally, a genetic correlation between indices of body condition and imuunocompetence supports the hypothesis that parasite resistance may be an important target of natural selection. Additional work is now required to test whether genetic covariance exists among other aspects of both condition and immunocompetence.