Nitric oxide control of the dorsal aorta and the intestinal vein of the Australian short-finned eel Anguilla australis

This study investigated the mechanisms by which nitric oxide (NO) regulates the dorsal aorta and the intestinal vein of the Australian short-finned eel Anguilla australis. NADPH diaphorase histochemistry and immunohistochemistry using a mammalian endothelial nitric oxide synthase (NOS) antibody could not demonstrate NOS in the endothelium of either blood vessel; however, NOS could be readily demonstrated in the endothelium of the rat aorta that was used as a control. Both blood vessels contained NADPH diaphorase positive nerve fibres and nerve bundles, and immunohistochemistry using a neural NOS antibody showed a similar distribution of neural NOS immunoreactivity in the perivascular nerves. In vitro organ bath physiology showed that a NO/soluble guanylyl cyclase (GC) system is present in the dorsal aorta and the intestinal vein, since the soluble GC inhibitor oxadiazole quinoxalin^-1 (ODQ; 10^–5 mol l^–1) completely abolished the vasodilatory effect of the NO donor, sodium nitroprusside (SNP; 10^–4 mol l^–1). In addition, nicotine (3x10^–4 mol l^–1) mediated a vasodilation that was not affected by removal of the endothelium. The nicotine-mediated dilation was blocked by the NOS inhibitor, Nω-nitro-arginine (L-NNA; 10^–4 mol l^–1), and ODQ (10^–5 mol l^–1). More specifically, the neural NOS inhibitor, Nω-propyl-L-arginine (10^–5 mol l^–1), significantly decreased the dilation induced by nicotine (3x10^–4 mol l^–1). Furthermore, indomethacin (10^–5 mol l^–1) did not affect the nicotine-mediated dilation, suggesting that prostaglandins are not involved in the response. Finally, the calcium ionophore A23187 (3x10^–6 mol l^–1) caused an endothelium-dependent dilation that was abolished in the presence of indomethacin. We propose the absence of an endothelial NO system in eel vasculature and suggest that neurally derived NO contributes to the maintenance of vascular tone in this species. In addition, we suggest that prostaglandins may act as endothelially derived relaxing factors in A. australis.

Bone-derived soluble factors and laminin-511 cooperate to promote migration, invasion and survival of bone-metastatic breast tumor cells

Tumor intrinsic and extrinsic factors are thought to contribute to bone metastasis but little is known about how they cooperate to promote breast cancer spread to bone. We used the bone-metastatic 4T1BM2 mammary carcinoma model to investigate the cooperative interactions between tumor LM-511 and bone-derived soluble factors in vitro. We show that bone conditioned medium cooperates with LM-511 to enhance 4T1BM2 cell migration and invasion and is sufficient alone to promote survival in the absence of serum. These responses were associated with increased secretion of MMP-9 and activation of ERK and AKT signaling pathways and were partially blocked by pharmacological inhibitors of MMP-9, AKT-1/2 or MEK. Importantly, pre-treatment of 4T1BM2 cells with an AKT-1/2 inhibitor significantly reduced experimental metastasis to bone in vivo. Promotion of survival and invasive responses by bone-derived soluble factors and tumor-derived LM-511 are likely to contribute to the metastatic spread of breast tumors to bone.

Vascular distribution of nitric oxide synthase and vasodilation in the Australian lungfish, Neoceratodus forsteri

The presence of nitric oxide synthase (NOS) and role of nitric oxide (NO) in vascular regulation was investigated in the Australian lungfish, Neoceratodus forsteri. No evidence was found for NOS in the endothelium of large and small blood vessels following processing for NADPH-diaphorase histochemistry. However, both NADPH-diaphorase histochemistry and neural NOS immunohistochemistry demonstrated a sparse network of nitrergic nerves in the dorsal aorta, hepatic artery, and branchial arteries, but there were no nitrergic nerves in small blood vessels in tissues. In contrast, nitrergic nerves were found in non-vascular tissues of the lung, gut and kidney. Dual-wire myography was used to determine if NO signalling occurred in the branchial artery of N. forsteri. Both SNP and SIN-1 had no effect on the pre-constricted branchial artery, but the particulate guanylyl cyclase (GC) activator, C-type natriuretic peptide, always caused vasodilation. Nicotine mediated a dilation that was not inhibited by the soluble GC inhibitor, ODQ, or the NOS inhibitor, L-NNA, but was blocked by the cyclooxygenase inhibitor, indomethacin. These data suggest that NO control of the branchial artery is lacking, but that prostaglandins could be endothelial relaxing factors in the vasculature of lungfish.

Study of polycyclic aromatic hydrocarbons emissions from burning of local wood species in Australia

Four kinds of Australian local wood species were burned in a domestic wood heater installed in a laboratory. The selected wood species include pine, red gum, yellow box and sugar gum, that are the most popular domestic fuel wood in Australia. Particulate matter emissions from burning of each load of wood were sampled isokinetically on filter media from the flue by standard stack emission sampling train. The particle laden filters then went for Gas Chromatography/ Mass Spectrometer (GC/MS) analysis to determine polycyclic aromatic hydrocarbons (PAHs) concentrations. The sampling was conducted under two different burning conditions – air inlet of the combustion chamber fully open and half open. Approximately 15 types of PAHs were detected. Emission factors were derived as microgram of PAHs /kg of wood burned. Total particulate emission factors were also obtained from gravimetric measurement before and after the sampling. PAH emission profiles for four species were generated from the results. Comparisons of emission factors have been conducted among different species of wood, as well as under different burning conditions, ie. fast burning and slowing burning. According to the derived emission factors, pine displayed the highest level of PAHs among the four species, followed by red gum and yellow box, whereas sugar gum showed the lowest level of PAHs. Emission factors were compared between each type of wood under two different burning conditions, the slow burning condition, which was air inlet half open, clearly showed higher PAH levels compared to the fast burning condition. Total PAH fractions on particulate matter were calculated and compared among wood types under two burning conditions. During the fast burning condition, red gum and pine have the higher percentage of PAH to total particulate matter emission than sugar gum and yellow box. When changed to slow burning, the PAH fraction on particulate matter are all increased with sugar gum having the largest increase.

Optimal redistribution when educational background matters

Higher education plays an important role in determining individuals lifetime
earnings. In turn, the decision to become educated depends to a large extent on innate ability and on family characteristics, including both family
wealth and educational background. In this paper, we abstract from family
income differences to concentrate on the effects of fiscal policies on the
decision to undertake higher education when the educational background
matters. In a dynamic framework, where successive generations are linked by educational background, we consider a government that uses both linear income taxation and a lump-sum subsidy to education. Conditions for
optimality of each policy are derived. The factors that determine the sign
and magnitude of the tax rate and the subsidy are identified and include
concerns for redistribution, efficiency and the educational externality on
future generations

The role of socio-cultural factors in the obesity epidemic

Obesity is socio-culturally distributed; that is the prevalence of obesity is known to vary according to socio-cultural factors, including socio-economic position, social roles and circumstance, and cultural factors. Further, these socio-cultural patterns are complex and specific to sex, age, and sometimes racial groups, as well as type of society, with patterns of relationships observed in developed countries sometimes reversed in developing countries. As described in Chapter 4, there is little doubt of the importance of the changing physical environment to the increases in obesity observed over the past several decades. However, far less attention has been paid to investigating the potential contribution of socio-cultural factors and to changes in the socio-cultural environment over time to the current obesity pandemic. The mechanisms through which socio-cultural factors may influence body weight and risk for obesity are also not well understood. In discussing socio-cultural influences we refer to systems of social relations (roles and relationships that define class, gender, ethnicity, and other social factors) and the meanings attached to these (1). For the purposes of this chapter, we focus on the impact of social, economic, and value systems on individuals' obesity-related behaviors (particularly, certain eating patterns and physical inactivity). In particular, we examine socio-cultural categories (socio-economic status, ethnicity, marital/family roles) for which evidence exists that rates of obesity are differentially distributed. We have not focused on the role of physical environmental factors, which is covered in Chapter 4, and we have largely restricted our focus to developed countries, from where the majority of the evidence for socio-cultural influences on obesity is derived. Issues relating to influences on obesity in developing countries are covered in detail in Chapter 5. This chapter provides an overview of the impact of socio-cultural influences on obesity in developed countries, and considers the potential pathways through which these influences may operate. The chapter concludes by speculating about the potential impact of societal trends on future rates and patterns of obesity in developed countries.

Factors associated with breast and cervical cancer screening behaviours

To investigate the factors associated with the use of screening mammography for breast cancer and cervical smear tests for cervical cancer, a theoretical framework was used comprising elements from the Health Belief Model, the Theory of Reasoned Action, and illness representations from the self-regulatory model. Items reflecting older women’s illness representations about cancer and cancer screening were derived from an earlier qualitative study. Using a highly structured interview schedule, telephone interviews were conducted with 1,200 women aged 50-70 years. There were considerable similarities between the factors associated with both mammography and cervical smear test behaviours. The factors associated with screening mammography behaviour were: perceived barriers, perceived benefits, social influence, the illness representations, and marital status. The factors associated with cervical smear test behaviour were: perceived barriers, perceived benefits, emotions as a cause of cancer, feeling frightened of cancer, the illness representations, having a usual general practitioner, and being younger.

A comparative study on economic factors of construction industries in Australia and China

The construction sector produces the facilities needed for a large majority of the production of goods and services, in which a sizeable proportion of Gross Domestic Product is generated. Recent trends in the globalisation of construction markets indicate that many countries consider construction industry competitiveness as crucial, and are working to increase construction productivity, in particular where the construction industries play an important role in their economic development. This paper first points out the research importance in international construction. Based on economic analyses of construction industries, a study is then carried out to focus on the economic sizes and benefits of the Chinese construction industry and to compare them with the Australian construction industry. Results derived from such an international construction comparison will assist in the Australian construction communities understanding the construction markets and industries in China and will benefit in international construction participation and cooperation.

Effects of gamma-tocopherol supplementation on thrombotic risk factors

Objective: The antioxidant activity of vitamin E is derived primarily from alpha-tocopherol (α-T) and gammatocopherol (γ-T). Results of epidemiological studies have demonstrated an inverse relationship between vitamin E intake and coronary disease. However, the results of clinical trials using α-T are equivocal. We determined the effect of 5 weeks of 100 mg/d or 200 mg/d γ-T supplementation on thrombotic markers such as platelet reactivity, lipid profile and the inflammation marker C-reactive protein (CRP). Methods and results: Fourteen healthy subjects consumed 100 mg/day while 13 consumed 200 mg/d of γ-T and 12 received placebo (soybean capsules with less than 5 mg/d γ-T) in a double-blinded parallel study design. Fasting pre and post dose blood samples were analysed. Blood γ-T concentrations increased significantly (p<0.05) relative to dose during the intervention period. Both groups receiving active ingredients showed significantly lower platelet activation after supplementation (p<0.05). Subjects consuming 100 mg/d γ-T had significantly decreased LDL cholesterol, platelet aggregation and mean platelet volume (MPV) (p<0.05). Little effect of γ-T was observed on other parameters. Conclusions: These data suggest that γ-T  supplementation may have a permissive role in decreasing the risk of
thrombotic events by improving lipid profile and reducing platelet activity.

Neurally-derived nitric oxide regulates vascular tone in pulmonary and cutaneous arteries of the toad, Bufo marinus

In this study, the role of nitric oxide (NO) in regulation of the pulmocutaneous vasculature of the toad, Bufo marinus was investigated. In vitro myography demonstrated the presence of a neural NO signaling mechanism in both arteries. Vasodilation induced by nicotine was inhibited by the soluble guanylyl cyclase (GC) inhibitor, 1H-(1,2,4)oxadiazolo(4,3-a)quinoxalin-1-one, and the NO synthase (NOS) inhibitor, N^ω-nitro-_L-arginine (_L-NNA). Removal of the endothelium had no significant effect on the vasodilation. Furthermore, pretreatment with N⁵-(1-imino-3-butenyl)-_L-ornithine (vinyl-_L-NIO), a more specific inhibitor of neural NOS, caused a significant decrease in the nicotine-induced dilation. In the pulmonary artery only, a combination of _L-NNA and the calcitonin gene-related peptide (CGRP) receptor antagonist, CGRP(_8-37), completely blocked the nicotine-induced dilation. In both arteries, the vasodilation was also significantly decreased by glibenclamide, an ATP-sensitive K⁺ (K⁺_ATP) channel inhibitor. Levcromakalim, a K⁺_ATP channel opener, caused a dilation that was blocked by glibenclamide in both arteries. In the pulmonary artery, NO donor-mediated dilation was significantly decreased by pretreatment with glibenclamide. The physiological data were supported by NADPH-diaphorase histochemistry and immunohistochemistry, which demonstrated NOS in perivascular nerve fibers but not the endothelium of the arteries. These results indicate that the pulmonary and cutaneous arteries of B. marinus are regulated by NO from nitrergic nerves rather than NO released from the endothelium. The nitrergic vasodilation in the arteries appears to be caused, in part, via activation of K⁺_ATP channels. Thus, NO could play an important role in determining pulmocutaneous blood flow and the magnitude of cardiac shunting.

Low back pain and disability in community-based women : prevalence and association factors

Objective: Although low back pain is characterized by both pain and disability, there is a paucity of studies that have concurrently examined risk factors for these features in community-dwelling women. We aimed to investigate the prevalence and identify factors associated with both back pain and disability.

Design: A questionnaire was mailed to 542 women from a community-based research database. Detailed demographic data were collected, including participants' menopause, relationship, and employment status. Point and period prevalence estimates for back pain were derived. Participants were classified based on pain intensity and disability scores calculated from the Chronic Pain Grade Questionnaire, and factors associated with high levels of pain and disability were examined.

Results: A total of 506 (93.4%) women completed the questionnaire. More than 90% of participants had experienced low back pain, with 75.1% and 22.5% reporting pain in the past 12 months and currently, respectively. Seven percent of women reported a high level of disability and 16% reported high-intensity pain. Women with higher levels of disability were more likely to have a higher body mass index and to have pain currently, whereas those with greater pain intensity were more likely to be younger, have a higher body mass index, not be employed outside the home, drink alcohol, and have current pain.

Conclusions: Low back pain is a common problem for community-based women. A high body mass index and current pain were factors independently associated with both high pain intensity and disability. Longitudinal investigation is required to determine the predictive nature of these factors and their potential role in preventing pain and disability.

Ecological and life-history factors influencing the evolution of maternal antibody allocation : a phylogenetic comparison

Maternally derived yolk antibodies provide neonates with immune protection in early life at negligible cost to mothers. However, developmental effects on the neonate's future immunity are potentially costly and thus could limit yolk antibody deposition. The benefits to neonatal immunity must be balanced against costs, which may depend on neonate vulnerability to pathogens, developmental trajectories and the immunological strategies best suited to a species' pace of life. We measured yolk antibodies and life-history features of 23 species of small Neotropical birds and assessed the evidence for each of several hypotheses for life history and ecological effects on the evolution of yolk antibody levels. Developmental period and yolk antibodies are negatively related, which possibly reflect the importance of humoral immune priming through antigen exposure, and selection to avoid autoimmunity, in species with a slower pace of life. There is also a strong relationship between body size and yolk antibody concentration, suggesting that larger species are architecturally equipped to produce and transfer higher concentrations of antibodies. These results suggest that developmental effects of maternally derived antibodies, such as imprinting effects on B-cell diversity or autoimmune effects, are important and deserve more consideration in future research.

Serum levels of brain-derived neurotrophic factor in schizophrenia on a hypocaloric diet

Dietary factors influence BDNF in animal studies, but there is no comparable data in clinical populations. We examined the effect of a dietary intervention on BDNF serum levels in 67 DSM-IV schizophrenic outpatients (51 males and 16 females). Two groups were assessed in a cross-sectional study: one on a hypocaloric diet (HD) and the other not on a hypocaloric diet. Weight, height and BMI data were collected concurrently with 5-ml blood sampling of each subject. BDNF levels were measured with a sandwich-ELISA. The blood sample was obtained a minimum of one month after the exposure to dietary intervention. Serum BDNF levels were significantly higher in patients on the HD (p = 0.023). Additional research examining the interaction among patterns of nutritional food behavior and underlying physiopathology may result in insights upon which evidence-based decisions regarding dietary interventions can be made in people identified with major psychiatric disorders, such as schizophrenia.

BDNF, metabolic risk factors, and resistance training in middle-aged individuals

Introduction and Purpose: Brain-derived neurotrophic factor (BDNF) and physical inactivity contribute to the development of the metabolic syndrome (MetS). There appears to be an association between BDNF and risk factors for MetS, and the effects of resistance training (RT) on BDNF and metabolic risk in middle-aged individuals with high and low numbers of metabolic risk factors (HiMF and LoMF, respectively) are unclear and are the focus of this research.

Methods: Forty-nine men (N = 25) and women (N = 24) aged 50.9 ± 6.2 yr were randomized to four groups, HiMF training (HiMFT), HiMF control (HiMFC), LoMF training (LoMFT), and LoMF control (LoMFC). Before and after 10 wk of RT, participants underwent tests for muscle strength and anthropometry, and a fasting blood sample was taken. Data were analyzed using Spearman correlations and repeated-measures ANOVA.

Results: BDNF was positively correlated with plasma triglycerides, glucose, HbA1C, and insulin resistance. BDNF was elevated in HiMF compared with LoMF (904.9 ± 270.6 vs 709.6 ± 239.8 respectively, P = 0.01). Training increased muscle strength and lean body mass but had no effect on BDNF levels or any examined risk factors.

Conclusion: BDNF levels correlated with risk factors for MetS and were elevated in individuals with HiMF. RT had no effect on BDNF levels or other risk factors for MetS. As RT has an effect on muscle strength and lean body mass, it should be added to other nonpharmacological interventions for middle-aged individuals with HiMF such as aerobic and/or diet.

Empirical investigation of critical success factors for implementing business intelligence systems in multiple engineering asset management organisations

Engineering asset management organisations (EAMOs) are increasingly motivated to implement business intelligence (BI) systems in response to dispersed information environments and compliance requirements. However, the implementation of a business intelligence (BI) system is a complex undertaking requiring considerable resources. Yet, so far, there are few defined critical success factors (CSFs) to which management can refer. Drawing on the CSFs framework derived from a previous Delphi study, a multiple-case design was used to examine how these CSFs could be implemented by five EAMOs. The case studies substantiate the construct and applicability of the CSFs framework. These CSFs are: committed management support and sponsorship, a clear vision and well-established business case, business-centric championship and balanced team composition, a business-driven and iterative develop ment approach, user-oriented change management, a business-driven, scalable and flexible technical framework, and sustainable data quality and integrity. More significantly, the study further reveals that those organisations which address the CSFs from a business orientation approach will be more likely to achieve better results.