Desensitization to medical examining equipment through learner control in a child with severe mental retardation

While the psychological literature is replete with examples of desensitization to phobic stimuli, few studies have documented successful interventions conducted with individuals identified as mentally retarded. The study describes desensitization to basic medical examining equipment in a youngster with severe mental retardation and autistic tendencies. Following desensitization to feared stimuli through the repeated exposure of baseline, intervention was initiated on the remaining feared stimuli through a learner control technique which combined modeling, behavioral rehearsal, and a variation of contact desensitization (Ritter, 1968). Results of a return-to-baseline design suggested that the medical examinations feared most by the child were of the same functional response class and that they did respond positively to intervention. Discussion of the methods and results provides practical implications for health professionals as well as offering hypotheses regarding the potential communicative and adaptive functions phobic manifestations serve in persons who experience significant handicapping conditions

Dose and life stage-dependent effects of dietary beta-carotene supplementation on the growth and development of the Booroolong frog

Carotenoids are known for their antioxidant capacity and are considered to play an important role in vertebrate growth and development. However, evidence for their beneficial effects remains limited, possibly because very few studies have tested for dose effects across different life stages. The present study investigated the effect of various doses of dietary beta-carotene supplements on the growth and development of larval and post-metamorphic Booroolong frogs (Litoria booroolongensis). Larval and post-metamorphic basal diets (containing 0.015 and 0.005 mg g−1 total carotenoids, respectively) were supplemented with beta-carotene at one of four concentrations: 0 mg g−1 , 0.1 mg g−1 , 1 mg g−1 and 10 mg g−1 . Each treatment included 72 replicate individuals, and individuals remained on the same diet treatment over both life stages (spanning 53 experimental weeks). Our results show that larvae receiving an intermediate (1 mg g−1 ) beta-carotene supplement dose grew faster than unsupplemented larvae (0 mg g−1 ), and metamorphosed earlier. After metamorphosis, there was no effect of the lowest supplement dose (0.1 mg g−1 ) on growth and development. However, juveniles fed the highest supplement dose (10 mg g−1 ) displayed significantly smaller body mass and lower body condition, compared to all other supplement doses, from 4-months through to sexual maturity (7-months). These findings indicate that beta-carotene supplementation has positive effects on growth and development, but only at intermediate doses, and only in the larval life stage. This knowledge may assist with amphibian conservation by expediting the rate that metamorphs can be generated in captive breeding programmes. More broadly, this is the first study to demonstrate both dose and life stagedependent effects of dietary beta-carotene supplementation on vertebrate growth and development

3 hours of perfusion culture prior to 28 days of static culture, enhances osteogenesis by human cells in a collagen GAG scaffold.

In tissue engineering bioreactors can be used to aid in the in vitro development of new tissue by providing biochemical and physical regulatory signals to cells and encouraging them to undergo differentiation and/or to produce extracellular matrix prior to in vivo implantation. This study examined the effect of short term flow perfusion bioreactor culture, prior to long term static culture, on human osteoblast cell distribution and osteogenesis within a collagen glycosaminoglycan (CG) scaffold for bone tissue engineering. Human Foetal Osteoblasts (hFOB 1.19) were seeded onto CG scaffolds and pre-cultured for 6 days. Constructs were then placed into the bioreactor and exposed to 3×1hr bouts of steady flow (1ml/min) separated by 7hrs of no flow over a 24hr period. The constructs were then cultured under static osteogenic conditions for up to 28 days. Results show that the bioreactor and static culture control groups displayed similar cell numbers and metabolic activity. Histologically however, peripheral cell-encapsulation was observed in the static controls, whereas, improved migration and homogenous cell distribution was seen in the bioreactor groups. Gene expression analysis showed that all osteogenic markers investigated displayed greater levels of expression in the bioreactor groups compared to static controls. While static groups showed increased mineral deposition; mechanical testing revealed that there was no difference in the compressive modulus between bioreactor and static groups. In conclusion, a flow perfusion bioreactor improved construct homogeneity by preventing peripheral encapsulation whilst also providing an enhanced osteogenic phenotype over static controls. © 2010 Wiley Periodicals, Inc

Effects of two contrast training programs on jump performance in rugby union players during a competition phase

Purpose: There is little literature comparing contrast training programs typically performed by team-sport athletes within a competitive phase. We compared the effects of two contrast training programs on a range of measures in high-level rugby union players during the competition season. Methods: The programs consisted of a higher volume-load (strength-power) or lower volume-load (speed-power) resistance training; each included a tapering of loading (higher force early in the week, higher velocity later in the week) and was performed twice a week for 4 wk. Eighteen players were assessed for peak power during a bodyweight countermovement jump (BWCMJ), bodyweight squat jump (BWSJ), 50 kg countermovement jump (50CMJ), 50 kg squat jump (50SJ), broad jump (BJ), and reactive strength index (RSI; jump height divided by contact time during a depth jump). Players were then randomized to either training group and were reassessed following the intervention. Inferences were based on uncertainty in outcomes relative to thresholds for standardized changes. Results: There were small between-group differences in favor of strength-power training for mean changes in the 50CMJ (8%; 90% confidence limits, ±8%), 50SJ (8%; ±10%), and BJ (2%; ±3%). Differences between groups for BWCMJ, BWSJ, and reactive strength index were unclear. For most measures there were smaller individual differences in changes with strength-power training. Conclusion: Our findings suggest that high-level rugby union athletes should be exposed to higher volume-load contrast training which includes one heavy lifting session each week for larger and more uniform adaptation to occur in explosive power throughout a competitive phase of the season

Polyploidy breaks speciation barriers in Australian burrowing frogs Neobatrachus

Polyploidy has played an important role in evolution across the tree of life but it is still unclear how polyploid lineages may persist after their initial formation. While both common and well-studied in plants, polyploidy is rare in animals and generally less understood. The Australian burrowing frog genus Neobatrachus is comprised of six diploid and three polyploid species and offers a powerful animal polyploid model system. We generated exome-capture sequence data from 87 individuals representing all nine species of Neobatrachus to investigate species-level relationships, the origin and inheritance mode of polyploid species, and the population genomic effects of polyploidy on genus-wide demography. We describe rapid speciation of diploid Neobatrachus species and show that the three independently originated polyploid species have tetrasomic or mixed inheritance. We document higher genetic diversity in tetraploids, resulting from widespread gene flow between the tetraploids, asymmetric inter-ploidy gene flow directed from sympatric diploids to tetraploids, and isolation of diploid species from each other. We also constructed models of ecologically suitable areas for each species to investigate the impact of climate on differing ploidy levels. These models suggest substantial change in suitable areas compared to past climate, which correspond to population genomic estimates of demographic histories. We propose that Neobatrachus diploids may be suffering the early genomic impacts of climate-induced habitat loss, while tetraploids appear to be avoiding this fate, possibly due to widespread gene flow. Finally, we demonstrate that Neobatrachus is an attractive model to study the effects of ploidy on the evolution of adaptation in animals

Effect of short term diet restriction on gene expression in the bovine hypothalamus using next generation RNA sequencing technology

peer-reviewedThis work was funded through Teagasc Walsh Fellowship to Daragh Matthews (Project Number: RMIS 5756).Background Negative energy balance (NEB) is an imbalance between energy intake and energy requirements for lactation and body maintenance affecting high-yielding dairy cows and is of considerable economic importance due to its negative impact on fertility and health in dairy herds. It is anticipated that the cow hypothalamus experiences extensive biochemical changes during the early post partum period in an effort to re-establish metabolic homeostasis. However, there is variation in the tolerance to NEB between individual cows. In order to understand the genomic regulation of ovulation in hypothalamic tissue during NEB, mRNA transcriptional patterns between tolerant and sensitive animals were examined. A short term dietary restriction heifer model was developed which induced abrupt onset of anoestrus in some animals (Restricted Anovulatory; RA) while others maintained oestrous cyclicity (Restricted Ovulatory; RO). A third control group (C) received a higher level of normal feeding. Results A total of 15,295 genes were expressed in hypothalamic tissue. Between RA and C groups 137 genes were differentially expressed, whereas between RO and C, 32 genes were differentially expressed. Differentially expressed genes were involved in the immune response and cellular motility in RA and RO groups, respectively, compared to C group. The largest difference between groups was observed in the comparison between RA and RO heifers, with 1094 genes shown to be significantly differentially expressed (SDE). Pathway analysis showed that these SDE genes were associated with 6 canonical pathways (P < 0.01), of which neuroactive ligand-receptor interaction was the most significant. Within the comparisons the main over-represented pathway functions were immune response including neuroprotection (CXCL10, Q1KLR3, IFIH1, IL1 and IL8; RA v C and RA v RO); energy homeostasis (AgRP and NPY; RA v RO); cell motility (CADH1, DSP and TSP4; RO v C) and prevention of GnRH release (NTSR1 IL1α, IL1β, NPY and PACA; RA v RO). Conclusions This information will assist in understanding the genomic factors regulating the influence of diet restriction on fertility and may assist in optimising nutritional and management systems for the improvement in reproductive performance.Teagasc Walsh Fellowship Programm

ACCEPTED MANUSCRIPT 1 Substrate stiffness and contractile behaviour modulate the functional maturation of osteoblasts on a collagen GAG scaffold

Please cite this article as: Keogh, M.B., Brien, F.J., Daly, J.S., Substrate stiffness and contractile behaviour modulate the functional maturation of osteoblasts on a collagen GAG scaffold, Acta Biomaterialia (2010), doi: 10.1016/ j.actbio. 2010.06.001 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. showed that all CG substrates allowed for cellular attachment, infiltration and osteogenic differentiation. ACCEPTED MANUSCRIPT CG scaffolds treated with EDAC and GLUT, were mechanically stiffer, retained their original scaffold structure and resisted cellular contraction. Consequently they facilitated a 2-fold greater cell number probably due to pore architecture being maintained allowing for improved diffusion of nutrients. On the other hand, the less stiff substrates crosslinked with DHT allowed for increased cell-mediated scaffold contraction; contracting by 70% following 6 weeks (p&lt;0.01) of culture. This reduction in scaffold area resulted in cells reaching the centre of the scaffold quicker up to 4 weeks; however, at 6 weeks all scaffolds showed similar levels of cellular infiltration with higher cell numbers found on the stiffer EDAC and GLUT-treated scaffolds. Analysis of osteogenesis showed, that scaffolds crosslinked with DHT expressed higher levels of the late stage bone formation markers osteopontin and osteocalcin (p&lt;0.01) and increased levels of mineralisation. In conclusion, the more compliant CG scaffolds allowed for cellmediated contraction and supported a greater level osteogenic maturation of MC3T3 cells while the stiffer, non contractible scaffolds resulted in lower levels of cell maturation but higher cell numbers on the scaffold. Therefore, we find scaffold stiffness has different effects on differentiation and cell number whereby the increased cell-mediated contraction facilitated by the less stiff scaffolds positively modulates osteoblast differentiation while reducing cell numbers