Paid employment of mothers and fathers of an adult child with multiple disabilities

Background Paid employment is increasingly undertaken by mothers as their children age, with the majority of women being in employment by the time their offspring are adult. Opportunities to engage in employment appear to be reduced for mothers of children with disabilities; however, little is known about the employment of mothers or fathers of adults with disabilities. Method Data were collected regarding the employment decisions of parents of a young adult with multiple disabilities and contrasted with those of parents whose children were all developing normally. Twenty-five mothers and 12 fathers of a young adult with multiple disabilities were interviewed, as were 25 comparison mothers and 19 comparison fathers. Data collected included hours of work, reasons for employment status, attitudes towards work and child care, and psychological well-being. Results Clear differences were found between the two groups. Mothers and fathers of a child with multiple disabilities showed different engagement patterns with the paid workforce from comparison parents. Hours of work for fathers of a young adult with multiple disabilities showed a bi-modal distribution, with some fathers working fewer hours than usual and others working very long hours. For mothers in both groups, the number of hours in paid employment was negatively associated with reports of psychological problems. Conclusions Increased attention needs to be given to the employment opportunities of parents of children with disabilities since employment appears to play a protective role for mothers, in particular. Services provided to adults with disabilities will need to change if parents are to have the same life chances as parents without adult offspring with a disability.

Familial adult renal neoplasia

Our understanding of the molecular mechanisms underlying the tumorigenesis of renal cell carcinoma (RCC) has partially come from studies of RCC related familial cancer syndromes such as von Hippel-Lindau (VHL) disease and hereditary papillary RCC (HPRC). These studies have led to the identification of RCC related genes, which, besides allowing accurate diagnosis of these diseases, have been found mutated or abnormally expressed in the sporadic counterparts of these familial renal tumours. To date, a number of renal tumour related syndromes have been described. We review recent advances in this field and discuss a genetic approach to managing familial cases of renal tumours occasionally encountered by cancer geneticists and urologists.

DMSP in corals and benthic algae from the Great Barrier Reef

In this study the first measurements of DMSP in six species of corals and ten species of benthic algae collected from four coral reefs in the Great Barrier Reef are reported, together with DMSP measurements made on cultured zooxanthellae. Concentrations ranged from 21 to 3831 (mean=743) fmol DMSP zooxanthellae(-1) in corals, 0.16 to 2.96 nmol DMSP cm(-2) (mean=90) for benthic macroalgae, and 48-285 fmol DMSP zooxanthellae(-1) (mean=153) for cultured zooxanthellae. The highest concentrations of DMSP in corals occurred in Acropora formosa (mean= 371 fmol DMSP zooxanthellae(-1)) and Acropora palifera (mean=3341 fmol DMSP zooxanthellae(-1)) with concentrations in A. palifera the highest DMSP concentrations reported in corals examined to date. As well as inter-specific differences in DMSP, intra-specific variation was also observed. Adjacent colonies of A. formosa that are known to have different thermal bleaching thresholds and morphologically distinct zooxanthellae, were also observed to have different DMSP concentrations, with the zooxanthellae in the colony that bleached containing DMSP at an average concentration of 436 finol zooxanthellae(-1), whilst the non-bleaching colony contained DMSP at an average concentration of 171 finol zooxanthellae(-1). The results of the present study have been used to calculate the area normalized DMSP concentrations in benthic algae (mean=0.015 mmol m(-2)) and corals (mean=2.22 mmol m(-2)) from the GBR. This data indicates that benthic algae and corals are a significant reservoir of DMSP in GBR waters. (C) 2002 Published by Elsevier Science Ltd.

Population pharmacokinetics of tacrolimus in adult kidney transplant recipients

Objectives: The aims of this study were to investigate the population pharmacokinetics of tacrolimus in adult kidney transplant recipients and to identify factors that explain variability. Methods: Population analysis was performed on retrospective data from 70 patients who received oral tacrolimus twice daily. Morning blood trough concentrations were measured by liquid chromatography-tandem mass spectrometry. Maximum likelihood estimates were sought for apparent clearance (CL/F) and apparent volume of distribution (V/F), with the use of NONMEM (GloboMax LLC, Hanover, Md). Factors screened for influence on these parameters were weight, age, gender, postoperative day, days of tacrolimus therapy, liver function tests, creatinine clearance, hematocrit fraction, corticosteroid dose, and potential interacting drugs. Results. CL/F was greater in patients with abnormally low hematocrit fraction (data from 21 patients only), and it decreased with increasing days of therapy and AST concentrations (P

Prospective independent validation of APACHE III models in an Australian tertiary adult intensive care unit

Evaluation of the performance of the APACHE III (Acute Physiology and Chronic Health Evaluation) ICU (intensive care unit) and hospital mortality models at the Princess Alexandra Hospital, Brisbane is reported. Prospective collection of demographic, diagnostic, physiological, laboratory, admission and discharge data of 5681 consecutive eligible admissions (1 January 1995 to 1 January 2000) was conducted at the Princess Alexandra Hospital, a metropolitan Australian tertiary referral medical/surgical adult ICU. ROC (receiver operating characteristic) curve areas for the APACHE III ICU mortality and hospital mortality models demonstrated excellent discrimination. Observed ICU mortality (9.1%) was significantly overestimated by the APACHE III model adjusted for hospital characteristics (10.1%), but did not significantly differ from the prediction of the generic APACHE III model (8.6%). In contrast, observed hospital mortality (14.8%) agreed well with the prediction of the APACHE III model adjusted for hospital characteristics (14.6%), but was significantly underestimated by the unadjusted APACHE III model (13.2%). Calibration curves and goodness-of-fit analysis using Hosmer-Lemeshow statistics, demonstrated that calibration was good with the unadjusted APACHE III ICU mortality model, and the APACHE III hospital mortality model adjusted for hospital characteristics. Post hoc analysis revealed a declining annual SMR (standardized mortality rate) during the study period. This trend was present in each of the non-surgical, emergency and elective surgical diagnostic groups, and the change was temporally related to increased specialist staffing levels. This study demonstrates that the APACHE III model performs well on independent assessment in an Australian hospital. Changes observed in annual SMR using such a validated model support an hypothesis of improved survival outcomes 1995-1999.

Systemic administration of interleukin-1 beta activates select populations of central amygdala afferents

The central nucleus of the amygdala (CeA) is activated robustly by an immune challenge such as the systemic administration of the proinflammatory cytokine interleukin-1beta (IL-1beta). Because IL-1beta is not believed to cross the blood-brain barrier in any significant amount, it is likely that IL-1beta elicits CeA cell recruitment by means of activation of afferents to the CeA. However, although many studies have investigated the origins of afferent inputs to the CeA, we do not know which of these also respond to IL-1beta. Therefore, to identify candidate neurons responsible for the recruitment of CeA cells by an immune challenge, we iontophoretically deposited a retrograde tracer, cholera toxin b-subunit (CTb), into the CeA of rats 7 days before systemic delivery of IL-1beta (1 mug/kg, i.a.). By using combined immunohistochemistry, we then quantified the number of Fos-positive CTb cells in six major regions known to innervate the CeA. These included the medial prefrontal cortex, paraventricular thalamus (PVT), ventral tegmental area, parabrachial nucleus (PB), nucleus tractus solitarius, and ventrolateral medulla. Our results show that after deposit of CTb into the CeA, the majority of double-labeled cells were located in the PB and the PVT, suggesting that CeA cell activation by systemic IL-1beta is likely to arise predominantly from cell bodies located in these regions. These findings may have significant implications in determining the central pathways involved in generating acute central responses to a systemic immune challenge. J. Comp. Neurol. 452:288-296, 2002. (C) 2002 Wiley-Liss, Inc.

Multiple maps and activity-dependent representational plasticity in the anterior Wulst of the adult barn owl (Tyto alba)

In the present study we addressed the issue of somatosensory representation and plasticity in a nonmammalian species, the barn owl. Multiunit mapping techniques were used to examine the representation of the specialized receptor surface of the claw in the anterior Wulst. We found dual somatotopic mirror image representations of the skin surface of the contralateral claw. In addition, we examined both representations 2 weeks after denervation of the distal skin surface of a single digit. In both representations, the denervated digital representation became responsive to stimulation of the adjacent, mutually functional, digit. The mutability and multiple representations indicates that the Wulst provides the owl with sensory processing capabilities analogous to those in mammals.

Selective ingestion of pelagic versus benthic algae by the cockle Cerastoderma edule (Linne, 1758)

The pre-ingestive selection of microphytobenthic algae by the cockle Cerastoderma edule was studied in comparison with diets containing the pelagic diatom Phaeodactylum tricomutum. Treatments with the different diets covered a range of seston concentrations and organic content similar to field conditions. Rejection rates of C. edule exposed to the different treatments were significantly correlated with the concentration of total particulate matter. No significant differences in total rejection rates were found between pelagic and benthic diets. Organic rejection rate was significantly correlated with particulate organic matter of the treatments and no significant differences were found between both diets. Selection efficiency was significantly correlated with particulate organic matter concentration in both diets and no significant differences were found between the diets. Analysis of the pseudofeces composition by flow cytometry from cockles exposed to a mixed diet of microphytobenthic algae and P. tricornutum, showed a preferential ingestion of the pelagic diatom. Benthic species, such as small pennates and Navicula sp., were preferentially ingested in comparison to larger microphytobenthic species. The largest microphytobenthic species, Cylindrotheca sp., was significantly rejected. In general, C. edule is an opportunistic filter feeder that takes advantage of both pelagic and benthic algal cells.

Depletion of benthic invertebrates by bar-tailed godwits Limosa lapponica in a subtropical estuary

This study (1) investigated functional (capture rate, foraging success) and numerical (density) responses of bar-tailed godwits Limosa lapponica to an experimental decrease in densities of their prey, and (2) estimated seasonal depletion of the stock of their main prey, the mictyrid crab Mictyris longicarpus, in a subtropical estuary. It was predicted that if intake rates of the godwits are in the vicinity of the gradient section of a functional response curve, i.e. are directly determined by prey density, they will respond rapidly to experimental reduction in the density of their prey. Bar-tailed godwits did respond rapidly, both functionally and numerically, to a decrease in the density of M longicarpus, indicating that their intake rate was limited by food availability. The estimated seasonal depletion of the stocks of Mictyris by the godwits was 88 % of the initial standing stock. Despite the virtual disappearance of Mictyris from sediment samples through the course of a non-breeding season, local densities of godwits did not change between October and March, implying that adequate rates of intake could be maintained throughout their residence period.

Differences in benthic fauna and sediment among mangrove (Avicennia marina var. australasica) stands of different ages in New Zealand

Management of coastal environments requires understanding of ecological relationships among different habitats and their biotas. Changes in abundance and distribution of mangroves, like those of other coastal habitats, have generally been interpreted in terms of changes in biodiversity or fisheries resources within individual stands. In several parts of their range, anthropogenically increased inputs of sediment to estuaries have led to the spread of mangroves. There is, however, little information on the relative ecological properties, or conservational values, of stands of different ages. The faunal, floral and sedimentological properties of mangrove (Avicennia marina var. australasica) stands of two different ages in New Zealand has been compared. Older (>60 years) and younger (3-12 years) stands showed clear separation on the basis of environmental characteristics and benthic macrofauna. Numbers of faunal taxa were generally larger at younger sites, and numbers of individuals of several taxa were also larger at these sites. The total number of individuals was not different between the two age-classes, largely due to the presence of large numbers of the surface-living gastropod Potamopyrgus antipodarum at the older sites. It is hypothesized that as mangrove stands mature, the focus of faunal diversity may shift from the benthos to animals living on the mangrove plants themselves, such as insects and spiders, though these were not included in the present study. Differences in the faunas were coincident with differences in the nature of the sediment. Sediments in older stands were more compacted and contained more organic matter and leaf litter. Measurement of leaf chemistry suggested that mangrove plants in the younger stands were able to take up more N and P than those in the older stands. (C) 2003 Elsevier Science B.V. All rights reserved.

Effects of habitat characteristics and climate on the distribution and colouration of Dusky Moorhens (Gallinula tenebrosa) in south-east Queensland

We determined which factors predict the presence and abundance of Dusky Moorhens (Gallinula tenebrosa) at wetlands by surveying the ecological and habitat characteristics of 62 sites across south-east Queensland. Moorhens were observed in 48 of the sites sampled. They were more likely to be found at sites surrounded by taller terrestrial vegetation and where free-floating and attached aquatic vegetation was more abundant. The number of moorhens found at a site increased in relation to vegetation height, the abundance of attached aquatic vegetation and the number of purple swamphens observed. These results suggest that there are ecological constraints on the distribution of moorhens, and that food abundance and the availability of suitable nesting sites determine the overall distribution and abundance of moorhens in wetlands. Adult moorhens develop brightly coloured fleshy frontal shields, bills and legs when breeding, although in some populations birds maintain year-round colouration. We observed year-round breeding colouration in 23 out of 34 sampling sites that had moorhens and were surveyed in August. Coloured moorhens were found during winter at sites with higher minimum winter temperatures, and more abundant free-floating and submerged leafy vegetation. In addition, higher proportions of moorhens were coloured at sites with higher mean minimum temperatures. The retention of year-round breeding colouration appears to be restricted to areas with warmer winter temperatures and more abundant food. The results suggest that areas not occupied by moorhens are of inadequate quality to support breeding populations. We suggest that ecological constraints on independent breeding in Dusky Moorhens may have favoured the evolution of their unusual cooperative breeding system, which involves frequent mate-sharing by both sexes.

Evolution of additive and nonadditive genetic variance in development time along a cline in Drosophila serrata

Latitudinal clines provide natural systems that may allow the effect of natural selection on the genetic variance to be determined. Ten clinal populations of Drosophila serrata collected from the eastern coast of Australia were used to examine clinal patterns in the trait mean and genetic variance of the life-history trait egg-to-adult development time. Development time significantly lengthened from tropical areas to temperate areas. The additive genetic variance for development time in each population was not associated with latitude but was associated with the population mean development time. Additive genetic variance tended to be larger in populations with more extreme development times and appeared to be consistent with allele frequency change. In contrast, the nonadditive genetic variance was not associated with the population mean but was associated with latitude. Levels of nonadditive genetic variance were greatest in the region of the cline where the gradient in the change in mean was greatest, consistent with Barton's (1999) conjecture that the generation of linkage disequilibrium may become an important component of the genetic variance in systems with a spatially varying optimum.