Analysis of the TGF beta functional pathway in epithelial ovarian carcinoma

Epithelial ovarian carcinoma is often diagnosed at an advanced stage of disease and is the leading cause of death from gynaecological neoplasia. The genetic changes that occur during the development of this carcinoma are poorly understood. It has been proposed that IGFIIR, TGF beta1 and TGF beta RII act as a functional unit in the TGF beta growth inhibitory pathway, and that somatic loss-of-function mutations in any one of these genes could lead to disruption of the pathway and subsequent loss of cell cycle control. We have examined these 3 genes in 25 epithelial ovarian carcinomas using single-stranded conformational polymorphism analysis and DNA sequence analysis. A total of 3 somatic missense mutations were found in the TGF beta RII gene, but none in IGFRII or TGF beta1. An association was found between TGF beta RII mutations and histology, with 2 out of 3 clear cell carcinomas having TGF beta RII mutations. This data supports other evidence from mutational analysis of the PTEN and beta -catenin genes that there are distinct developmental pathways responsible for the progression of different epithelial ovarian cancer histologic subtypes. (C) 2001 Cancer Research Campaign.

Dieting and health in young Australian women

This paper examines the prevalence of dieting behaviours and correlates with physical and mental health in young Australian women who are participants in the Australian Longitudinal Stud of Women's Health. A total of 14 686 women aged 18-23 years, randomly selected from the National Medicare database, with over-sampling from rural and remote areas, responded to a questionnaire seeking dieting and health information. The results showed that 66.5 percent of the women had a BMI within the healthy weight range (18- < 25 kg/m(2)). However only 21.6 percent of these women were happy with their weight and almost half (46 percent) had dieted to lose weight in the last year (also one in five who had a BMI < 18.5 kg/m(2)). High frequency of dieting (rather than dieting per se) and earlier dieting onset were associated with poorer physical and mental health (including depression), more disordered eating (bingeing and purging), extreme weight and shape dissatisfaction and more frequent general health problems. The results suggest that there is a need for programmes that will enhance self esteem and weight/shape acceptance and promote more appropriate strategies for maintenance of healthy weight. Copyright (C) 2001 John Wiley & Sons, Ltd and Eating Disorders Association.

Synthesis of an analog of the thyroid hormone-binding protein transthyretin via regioselective chemical ligation

Transthyretin is an essential protein responsible for the transport of thyroid hormones and retinol in human serum and is also implicated in the amyloid diseases familial amyloidotic polyneuropathy and senile systemic amyloidosis. Its folding properties and stabilization by ligands are of current interest due to their importance in understanding and combating these diseases, Here we report the solid phase synthesis of the monomeric unit of a transthyretin analog (equivalent to 127 amino acids) using t-Boc chemistry and peptide ligation and its folding to form a functional 54-kDa tetramer, The monomeric unit of the protein was chemically synthesized in three parts (positions 1-51, 54-99, and 102-127) and ligated using a chemoselective thioether ligation chemistry. The synthetic protein was folded and assembled to a tetrameric structure in the presence of transthyretin's native ligand, thyroxine, as shown by gel filtration chromatography, native gel electrophoresis, transthyretin antibody recognition, and thyroid hormone binding. Other folding products included a high molecular weight aggregate as well as a transient dimeric species. This represents one of the largest macromolecules chemically synthesized to date and demonstrates the potential of protein chemical synthesis for investigations of protein-ligand interactions.

Semantic priming in Alzheimer's dementia: Evidence for dissociation of automatic and attentional processes

The nature of the semantic memory deficit in dementia of the Alzheimer's type (DAT) was investigated in a semantic priming task which was designed to assess both automatic and attention-induced priming effects. Ten DAT patients and 10 age-matched control subjects completed a word naming semantic priming task in which both relatedness proportion (RP) and stimulus-onset asynchrony (SOA) were varied. A clear dissociation between automatic and attentional priming effects in both groups was demonstrated; however, the DAT subjects pattern of priming deviated significantly from that of the normal controls. The DAT patients failed to produce any priming under conditions which encouraged automatic semantic processing and produced facilitation only when the RP was high. In addition, the DAT group produced hyperpriming, with significantly larger facilitation effects than the control group. These results suggest an impairment of automatic spreading activation in DAT and have implications for theories of semantic memory impairment in DAT as well as models of normal priming. (C) 2001 Academic Press.

Biogeographical concordance and efficiency of taxon indicators for establishing conservation priority in a tropical rainforest biota

Prioritizing areas for conservation requires the use of surrogates for assessing overall patterns of biodiversity. Effective surrogates will reflect general biogeographical patterns and the evolutionary processes that have given rise to these and their efficiency is likely to lie influenced by several factors, including the spatial scale of species turnover and the overall congruence of the biogeographical history. We examine patterns of surrogacy for insects, snails, one family of plants and vertebrates from rainforests of northeast Queensland, an area characterized by high endemicity and an underlying history of climate-induced vicariance. Nearly all taxa provided some level of prediction of the conservation values For others. However, despite an overall correlation of the patterns of species richness and complementarity, the efficiency of surrogacy was highly asymmetric.. snails and insects were strong predictors of conservation priorities for vertebrates, but not vice versa. These results confirm predictions that taxon surrogates can be effective in highly diverse tropical systems where there is a strong history of vicariant biogeography, but also indicate that correlated patterns for species richness and/or complementarity do not guarantee that one taxon will be efficient as a surrogate for another. In our case, the highly diverse and narrowly distributed invertebrates were more efficient as predictors than the less diverse and more broadly distributed vertebrates.

Functional roles of abdominal and back muscles during isometric axial rotation of the trunk

Electromyographic (EMG) studies have shown that a large number of trunk muscles are recruited during axial rotation. The functional roles of these trunk muscles in axial rotation are multiple and have not been well investigated. In addition, there is no information on the coupling torque at different exertion levels during axial rotation. The aim of the study was to investigate the functional roles of rectus abdominis. external oblique. internal oblique, latissimus dorsi, iliocostalis lumborum and multifidus during isometric right and left axial rotation at 100%, 70%, 50% and 30% maximum voluntary contractions (MVC) in a standing position. The coupling torques in sagittal and coronal planes were measured during axial rotation to examine the coupling nature of torque at different levels of exertions. Results showed that the coupled sagittal torque switches from nil to flexion at maximum exertion of axial rotation. Generally, higher EMG activities were shown at higher exertion levels for all the trunk muscles. Significant differences in activity between the right and left axial rotation exertions were demonstrated in external oblique, internal oblique, latissimus dorsi and iliocostalis lumborum while no difference was shown in rectus abdominis and multifidus. These results demonstrated the different functional roles of trunk muscles during axial rotation. This is important considering that the abdominal and back muscles not only produce torque but also maintain the spinal posture and stability during axial rotation exertions. The changing coupling torque direction in the sagittal plane when submaximal to maximal exertions were compared may indicate the complex nature of the kinetic coupling of trunk muscles. (C) 2001 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.

Surgical outcomes of a randomized prospective trial involving patients with a proximal femoral fracture

Background: An orthopaedic management/patient-focused care unit (OMPFCU) involving a dedicated orthopaedic-geriatrics liaison team was established at the Royal Brisbane Hospital in 1994 in an effort to safely accelerate rehabilitation of patients with proximal femoral fractures. Methods: The surgical outcomes of the patients were monitored in order to determine whether accelerated rehabilitation had any significant adverse effects on the surgical outcomes, measured by mortality, readmission to hospital, deep wound infection, fracture union delay, mobility and the revision surgery rate. Results: No significant difference was recorded in mortality and morbidity, deep wound infection and revision surgery rates between patients in the Royal Brisbane Hospital OMPFCU and those in standard care in the orthopaedic surgery wards. Conclusion: Accelerated rehabilitation for patients with a proximal femoral fracture in a major teaching hospital can be accomplished safely.

Co-activation of the abdominal and pelvic floor muscles during voluntary exercises

The response of the abdominal muscles to voluntary contraction of the pelvic floor (PF) muscles was investigated in women with no history of symptoms of stress urinary incontinence to determine whether there is co-activation of the muscles surrounding the abdominal cavity during exercises for the PF muscles. Electromyographic (EMG) activity of each of the abdominal muscles was recorded with fine-wire electrodes in seven parous females. Subjects contracted the PF muscles maximally in three lumbar spine positions while lying supine. In all subjects. the EMG activity of the abdominal muscles was increased above the baseline level during contractions of the PF muscles in at least one of the spinal positions. The amplitude of the increase in EMG activity of obliquus externus abdominis was greatest when the spine was positioned in flexion and the increase in activity of transversus abdominis was greater than that of rectus abdominis and obliquus externus abdominis when the spine was positioned in extension. In an additional pilot experiment. EMG recordings were made from the pubococcygeus and the abdominal muscles with fine-wire electrodes in two subjects during the performance of three different sub-maximal isometric abdominal muscle maneuvers. Both subjects showed an increase in EMG activity of the pubococcygeus with each abdominal muscle contraction. The results of these experiments indicate that abdominal muscle activity is a normal response to PF exercise in subjects with no symptoms of PF muscle dysfunction and provide preliminary evidence that specific abdominal exercises activate the PF muscles. Neurourol. Urodynam. 20:31-42, 2001. (C) 2001 Wiley-Liss, Inc.

Motorcycle exhaust burns in children

Objectives: To document and describe motorbike exhaust burns on children. Design, Patients and Setting: Departmental database and case note review of all children with motorbike exhaust burns seen at the Stuart Pegg Paediatric Burns Centre, Brisbane between January 1996 and October 2001. Main outcome measures: Number and age of children burned, circumstances of the injury, burns sustained, treatment required and long-term sequelae. Results: Twenty-four children, median age 8 years, sustained thermal burns, most commonly to the right lower leg. Thirteen children required surgery, and 17 required chronic scar management. Conclusions: We have identified motorbike exhausts as a cause of burns in children. The injuries received resulted in significant morbidity to these children and warrants a campaign airned at reducing the incidence of such injuries. (C) 2002 Published by Elsevier Science Ltd. and ISBI.

Integrability and exact spectrum of a pairing model for nucleons

A pairing model for nucleons, introduced by Richardson in 1966, which describes proton-neutron pairing as well as proton-proton and neutron-neutron pairing, is re-examined in the context of the quantum inverse scattering method. Specifically, this shows that the model is integrable by enabling the explicit construction of the conserved operators. We determine the eigenvalues of these operators in terms of the Bethe ansatz, which in turn leads to an expression for the energy eigenvalues of the Hamiltonian.

Human immunodeficiency virus type 1 reverse transcription is stimulated by Tat from other lentiviruses

The tat gene is required by HIV-1 for efficient reverse transcription and this function of Tat can be distinguished from its role in transcription by RNA polymerase II using tat point mutations that abrogate each function independently The mechanism of Tat's role in reverse transcription, however, is not known, nor is it known whether this role is conserved among trans-activating factors in other retroviruses. Here we examine the abilities of heterologous viral trans-activating proteins from jembrana disease virus (jTat), HIV-2 (Tat2), and equine infectious anemia virus (eTat) to substitute for HIV-1 Tat (Tat1) and restore reverse transcription in HIV-1 carrying an inactivated tat gene. Natural endogenous reverse transcription assays showed that trans-activators from some retroviruses (Tat2 and jTat, but not eTat) could substitute for Tat1 in complementation of HIV-1 reverse transcription. Finally, we show that Y47 is critical for Tat1 to function in reverse transcription, but not HIV-1 gene expression. We mutated the homologous position in jTat to H62Y and found it did not improve its ability to stimulate reverse transcription, but an H62A mutation did inhibit jTat complementation. These data highlight the finding that the role of Tat in reverse transcription is not related to trans-activation and demonstrate that other tat genes conserve this function. (C) 2002 Elsevier Science (USA).

Positive genetic correlation between female preference and offspring fitness

In many species, females display preferences for extreme male signal traits, but it has not been determined if such preferences evolve as a consequence of females gaining genetic benefits from exercising choice. If females prefer extreme male traits because they indicate male genetic quality that will enhance the fitness of offspring, a genetic correlation will evolve between female preference genes and genes that confer offspring fitness. We show that females of Drosophila serrata prefer extreme male cuticular hydrocarbon (CHC) blends, and that this preference affects offspring fitness. Female preference is positively genetically correlated with offspring fitness, indicating that females have gained genetic benefits from their choice of males. Despite male CHCs experiencing strong sexual selection, the genes underlying attractive CHCs also conferred lower offspring fitness, suggesting a balance between sexual selection and natural selection may have been reached in this population.