Gender differences in attitudes among those at risk for Huntington's disease

This report presents and discusses selected findings regarding gender differences from an Australian-based study that investigated attitudes of individuals at risk for Huntington's disease (HD) towards genetic risk and predictive testing. Clear gender differences emerged regarding perceived coping capacity with regard to predictive testing, as well as disclosure of the genetic risk for HD to others. Female participants were more likely to disclose their genetic risk to others, including their medical practitioners, while male participants were three times more fearful of disclosing their genetic risk to others. These findings are of interest in light of gender differences that have consistently been reported regarding the uptake of predictive testing for HD, other genetic conditions, and health services more generally. While gender differences cannot provide a fully explanatory framework for differential uptake of predictive genetic testing, men and women may experience and respond differently to the genetic risk for HD and possibly other inherited disorders. The meanings of genetic risk to men and women warrants further exploration, given anticipated increases in genetic testing for more common conditions, especially if post-test interventions are possible. These issues are also relevant within the context of individuals' concerns about the potential for discrimination on the basis of genetic risk or genetic test information.

Modeling the economic losses from pressure ulcers among hospitalized patients in Australia

The objective of this study was to predict the number of cases of pressure ulcer, the bed days lost, and the economic value of these losses at Australian public hospitals. All adults (>= 18 years of age) with a minimum stay of 1 night and discharged from selected clinical units from all Australian public hospitals in 2001-02 were included in the study. The main outcome measures were the number of cases of pressure ulcer, bed days lost to pressure ulcer, and economic value of these losses. We predict a median of 95,695 cases of pressure ulcer with a median of 398,432 bed days lost, incurring median opportunity costs of AU$285 M. The number of cases, and so costs, were greatest in New South Wales and lowest in Australian Capitol Territory. We conclude that pressure ulcers represent a serious clinical and economic problem for a resource-constrained public hospital system. The most cost-effective, risk-reducing interventions should be pursued up to a point where the marginal benefit of prevention is equalized with marginal cost. By preventing pressure ulcers, public hospitals can improve efficiency and the quality of the patient's experience and health outcome.

Herbs or natural substances as complementary therapies for chronic kidney disease: ideas for future studies

Chronic kidney disease (CKD) is an increasingly common condition with limited treatment options that is placing a major financial and emotional burden on the community. The use of complementary and alternative medicines (CAMS) has increased many-fold over the past decade. Although several compelling studies show renal toxicities and an adverse outcome from use of some CAMS, there is also emerging evidence in the literature that some may be renoprotective. Many nephrologists are unaware of these potential therapeutic benefits in treating CKD, or they are reluctant to consider them in research trials for fear of adverse effects (including nephrotoxicity) or deleterious interaction with co-prescribed, conventional medicines. The increased use of self-prescribed CAMS by their patients suggests that practitioners and researchers should keep abreast of the current information on these agents. A primary goal of this article was to review the available scientific evidence for the use of herbs or natural substances as a complementary treatment for patients with CKD. A further goal was to report the literature on herbs that have been reported to cause kidney failure.

Unlocking pathology archives for molecular genetic studies: a reliable method to generate probes for chromogenic and fluorescent in situ hybridization

Chromogenic (CISH) and fluorescent ( FISH) in situ hybridization have emerged as reliable techniques to identify amplifications and chromosomal translocations. CISH provides a spatial distribution of gene copy number changes in tumour tissue and allows a direct correlation between copy number changes and the morphological features of neoplastic cells. However, the limited number of commercially available gene probes has hindered the use of this technique. We have devised a protocol to generate probes for CISH that can be applied to formalin-fixed, paraffin-embedded tissue sections (FFPETS). Bacterial artificial chromosomes ( BACs) containing fragments of human DNA which map to specific genomic regions of interest are amplified with phi 29 polymerase and random primer labelled with biotin. The genomic location of these can be readily confirmed by BAC end pair sequencing and FISH mapping on normal lymphocyte metaphase spreads. To demonstrate the reliability of the probes generated with this protocol, four strategies were employed: (i) probes mapping to cyclin D1 (CCND1) were generated and their performance was compared with that of a commercially available probe for the same gene in a series of 10 FFPETS of breast cancer samples of which five harboured CCND1 amplification; (ii) probes targeting cyclin-dependent kinase 4 were used to validate an amplification identified by microarray-based comparative genomic hybridization (aCGH) in a pleomorphic adenoma; (iii) probes targeting fibroblast growth factor receptor 1 and CCND1 were used to validate amplifications mapping to these regions, as defined by aCGH, in an invasive lobular breast carcinoma with FISH and CISH; and (iv) gene-specific probes for ETV6 and NTRK3 were used to demonstrate the presence of t(12; 15)(p12; q25) translocation in a case of breast secretory carcinoma with dual colour FISH. In summary, this protocol enables the generation of probes mapping to any gene of interest that can be applied to FFPETS, allowing correlation of morphological features with gene copy number.

A pragmatic 2 × 2 × 2 factorial cluster randomized controlled trial of educational outreach visiting and case conferencing in palliative care—methodology of the Palliative Care Trial [ISRCTN 81117481]

The demand for palliative care is increasing, yet there are few data on the best models of care nor well-validated interventions that translate current evidence into clinical practice. Supporting multidisciplinary patient-centered palliative care while successfully conducting a large clinical trial is a challenge. The Palliative Care Trial (PCT) is a pragmatic 2 x 2 x 2 factorial cluster randomized controlled trial that tests the ability of educational outreach visiting and case conferencing to improve patient-based outcomes such as performance status and pain intensity. Four hundred sixty-one consenting patients and their general practitioners (GPs) were randomized to the following: (1) GP educational outreach visiting versus usual care, (2) Structured patient and caregiver educational outreach visiting versus usual care and (3) A coordinated palliative care model of case conferencing versus the standard model of palliative care in Adelaide, South Australia (3:1 randomization). Main outcome measures included patient functional status over time, pain intensity, and resource utilization. Participants were followed longitudinally until death or November 30, 2004. The interventions are aimed at translating current evidence into clinical practice and there was particular attention in the trial's design to addressing common pitfalls for clinical studies in palliative care. Given the need for evidence about optimal interventions and service delivery models that improve the care of people with life-limiting illness, the results of this rigorous, high quality clinical trial will inform practice. Initial results are expected in mid 2005. (c) 2005 Elsevier Inc. All rights reserved.

A Score Test for Zero-Inflation in Correlated Count Data

To account for the preponderance of zero counts and simultaneous correlation of observations, a class of zero-inflated Poisson mixed regression models is applicable for accommodating the within-cluster dependence. In this paper, a score test for zero-inflation is developed for assessing correlated count data with excess zeros. The sampling distribution and the power of the test statistic are evaluated by simulation studies. The results show that the test statistic performs satisfactorily under a wide range of conditions. The test procedure is further illustrated using a data set on recurrent urinary tract infections. Copyright (c) 2005 John Wiley & Sons, Ltd.

Analysis of the effect of different NKT cell subpopulations on the activation of CD4 and CD8 T cells, NK cells, and B cells

Objective. NKT cells have diverse immune regulatory functions including activation of cells involved in Th1- and Th2-type immune activities. Most previous studies have investigated the functions of NKT cells as a single family but more recent evidence indicates the distinct functional properties of NKT cell subpopulation. This study aims to determine whether NKT cell subpopulations have different stimulatory activities on other immune cells that may affect the outcome of NKT cell-based immunotherapy. Methods. NKT cells and NKT cell subpopulations (CD4(+)CD8(-), CD4(-)CD8(+), CD4(-)CD8(+)) were cocultured with PBMC and their activities on immune cells including CD4(+) and CD8(+) T cells, NK cells, and B cells were assessed by flow cytometry. The production of cytokines in culture was measured by enzyme-linked immunsorbent assay. Results. The CD4(+)CD8(-) NKT cells demonstrated substantially greater stimulatory activities on CD4(+) T cells, NK cells, and B cells than other NKT cell subsets. The CD4(-)CD8(+) NKT cells showed the greatest activity on CD8(+) T cells, and were the only NKT cell subset that activated these immune cells. The CD4(-)CD8(-) NKT cells showed moderate stimulatory activity on CD4(+) T cells and the least activity on other immune cells. Conclusion. The results here suggest that NKT cell subpopulations differ in their abilities to stimulate other immune cells. This highlights the potential importance of manipulating specific NKT cell subpopulations for particular therapeutic situations and of evaluating subpopulations, rather than NKT cells as a group, during investigation of a possible role of NKT cells in various disease settings. (c) 2006 International Society for Experimental Hematology. Published by Elsevier Inc.

Kidney dysfunction and hypertension: Role for cadmium, P450 and heme oxygenases?

Cadmium (Cd) is a metal toxin of continuing worldwide concern. Daily intake of Cd, albeit in small quantities, is associated with a number of adverse health effects which are attributable to distinct pathological changes in a variety of tissues and organs. In the present review, we focus on its renal tubular effects in people who have been exposed environmentally to Cd at levels below the provisional tolerable intake level set for the toxin. We highlight the data linking such low-level Cd intake with tubular injury, altered abundance of cytochromes P450 (CYPs) in the kidney and an expression of a hypertensive phenotype. We provide updated knowledge on renal and vascular effects of the eicosanoids 20-hydroxyeicosatetraenoic acid (20-HETE) and eicosatrienoic acids (EETs), which are biologically active metabolites from arachidonate metabolism mediated by certain CYPs in the kidney. We note the ability of Cd to elicit oxidative stress and to alter metal homeostasis notably of zinc which may lead to augmentation of the defense mechanisms involving induction of the antioxidant enzyme heme oxygenase-1 (HO-1) and the metal binding protein metallothionein (MT) in the kidney. We hypothesize that renal Cd accumulation triggers the host responses mediated by HO-I and MT in an attempt to protect the kidney against injurious oxidative stress and to resist a rise in blood pressure levels. This hypothesis predicts that individuals with less active HO-1 (caused by the HO-1 genetic polymorphisms) are more likely to have renal injury and express a hypertensive phenotype following chronic ingestion of low-level Cd, compared with those having more active HO-1. Future analytical and molecular epidemiologic research should pave the way to the utility of induction of heme oxygenases together with dietary antioxidants in reducing the risk of kidney injury and hypertension in susceptible people.

Mechanisms of hematopoietic stem cell mobilization: When innate immunity assails the cells that make blood and bone

Mobilization is now used worldwide to collect large numbers of hematopoietic stem and progenitor cells (HSPCs) for transplantation. Although the first mobilizing agents were discovered largely by accident, discovery of more efficient mobilizing agents will require a better understanding of the molecular mechanisms responsible. During the past 5 years, a number of mechanisms have been identified, shedding new light on the dynamics of the hematopoietic system in vivo and on the intricate relationship between hematopoiesis, innate immunity, and bone. After briefly reviewing the mechanisms by which circulating HSPCs home into the bone marrow and what keeps them there, the current knowledge of mechanisms responsible for HSPC mobilization in response to hematopoietic growth factors such as granulocyte colony-stimulating factor, chemotherapy, chemokines, and polyanions will be discussed together with current strategies developed to further increase HSPC mobilization. (c) 2006 International Society for Experimental Hematology.

Identification of a novel frameshift mutation in the giant muscle filament titin in a large Australian family with dilated cardiomyopathy

Dilated cardiomyopathy (DCM) is an etiologically heterogeneous cardiac disease characterized by left ventricular dilation and systolic dysfunction. Approximately 25-30% of DCM patients show a family history of mainly autosomal dominant inheritance. We and others have previously demonstrated that mutations in the giant muscle filament titin (TTN) can cause DCM. However, the prevalence of titin mutations in familial DCM is unknown. In this paper, we report a novel heterozygous 1-bp deletion mutation (c.62890delG) in TTN that cosegregates with DCM in a large Australian pedigree (A3). The TTN deletion mutation c.62890delG causes a frameshift, thereby generating a truncated A-band titin due to a premature stop codon (p.E20963KfsX10) and the addition of ten novel amino acid residues. The clinical phenotype of DCM in kindred A3 demonstrates incomplete penetrance and variable expressivity. Finally, protein analysis of a skeletal muscle biopsy sample from an affected member did not reveal the predicted truncated titin isoform although the aberrant mRNA was present, suggesting posttranslational modification and degradation of the truncated protein. The identification of a novel disease-causing mutation in the giant titin gene in a third large family with DCM indicates that mutations in titin may account for a significant portion of the genetic etiology in familial DCM.

Pharmacological evaluation of an [I-123] labelled imidazopyridine-3-acetamide for the study of benzodiazepine receptors

In vitro binding of the iodinated imidazopyri dine, N',N'-dimethyl-6-methyl-(4'-[I-123]iodophenyl)imidazo[1,2-a]pyridine-3-acetamide [I-123]IZOL to benzodiazepine binding sites on brain cortex, adrenal and kidney membranes is reported. Saturation experiments showed that [I-123]IZOL, bound to a single class of binding site (n(H)=0.99) on adrenal and kidney mitochondrial membranes with a moderate affinity (K-d=30 nM). The density of binding sites was 22 +/- 6 and 1.2 +/- 0.4 pmol/mg protein on adrenal and kidney membranes, respectively. No specific binding was observed in mitochondrial-synaptosomal membranes of brain cortex. In biodistribution studies in rats, the highest uptake of [I-123]IZOL was found 30 min post injection in adrenals (7.5% ID/g), followed by heart, kidney, lung (1% ID/g) and brain (0.12% ID/g), consistent with the distribution of peripheral benzodiazepine binding sites. Pre-administration of unlabelled IZOL and the specific PBBS drugs, PK 11195 and Ro 5-4864 significantly reduced the uptake of [I-123]IZOL by 30% (p < 0.05) in olfactory bulbs and by 51-86% (p < 0.01) in kidney, lungs, heart and adrenals, while it increased by 30% to 50% (p < 0.01) in the rest of the brain and the blood. Diazepam, a mixed CBR-PBBS drug, inhibited the uptake in kidney, lungs, heart, adrenals and olfactory bulbs by 32% to 44% (p < 0.01) but with no effect on brain uptake and in blood concentration. Flumazenil, a central benzodiazepine drug and haloperidol (dopamine antagonist/sigma receptor drug) displayed no effect in [I-123]IZOL in peripheral organs and in the brain. [I-123]IZOL may deserve further development for imaging selectively peripheral benzodiazepine binding sites. (c) 2006 Elsevier Inc. All rights reserved.

Effect of training on the response of plasma vascular endothelial growth factor to exercise in patients with peripheral arterial disease

Expansion of the capillary network, or angiogenesis, occurs following endurance training. This process, which is reliant on the presence of VEGF (vascular endothelial growth factor), is an adaptation to a chronic mismatch between oxygen demand and supply. Patients with IC (intermittent claudication) experience pain during exercise associated with an inadequate oxygen delivery to the muscles. Therefore the aims of the present study were to examine the plasma VEGF response to acute exercise, and to establish whether exercise training alters this response in patients with IC. In Part A, blood was collected from patients with IC (n = 18) before and after (+ 20 and + 60 min post-exercise) a maximal walking test to determine the plasma VEGF response to acute exercise. VEGF was present in the plasma of patients (45.11 +/- 29.96 pg/ml) and was unchanged in response to acute exercise. Part B was a training study to determine whether exercise training altered the VEGF response to acute exercise. Patients were randomly assigned to a treatment group (TMT; n = 7) that completed 6 weeks of high-intensity treadmill training, or to a control group (CON; n = 6). All patients completed a maximal walking test before and after the intervention, with blood samples drawn as for Part A. Training had no effect on plasma VEGF at rest or in response to acute exercise, despite a significant increase in maximal walking time in the TMT group (915 + 533 to 1206 + 500 s; P = 0.009) following the intervention. The absence of a change in plasma VEGF may reflect altered VEGF binding at the endothelium, although this cannot be confirmed by the present data.

Assessment of epidermal cell viability by near infrared multi-photon microscopy following ballistic delivery of gold micro-particles

The use of gene guns in ballistically delivering DNA vaccine coated gold micro-particles to skin can potentially damage targeted cells, therefore influencing transfection efficiencies. In this paper, we assess cell death in the viable epidermis by non-invasive near infrared two-photon microscopy following micro-particle bombardment of murine skin. We show that the ballistic delivery of micro-particles to the viable epidermis can result in localised cell death. Furthermore, experimental results show the degree of cell death is dependant on the number of micro-particles delivered per unit of tissue surface area. Micro-particles densities of 0.16 +/- 0.27 (mean +/- S.D.), 1.35 +/- 0.285 and 2.72 +/- 0.47 per 1000 mu m(2) resulted in percent deaths of 3.96 +/- 5.22, 45.91 +/- 10.89, 90.52 +/- 12.28, respectively. These results suggest that optimization of transfection by genes administered with gene guns is - among other effects - a compromise of micro-particle payload and cell death. (c) 2005 Elsevier Ltd. All rights reserved.