John Connell

Losing ground? Tuvalu, the greenhouse effect and the garbage can

: Greenhouse-induced sea-level rise (SLR) threatens coral atolls and particularly the few atoll states, such as Tuvalu. This central Pacific island microstate has minimal economic development options, and has increasingly perceived emigration and remittances as a development strategy, despite restricted opportunities. Internal migration, in search of wage employment, has brought almost half the national population to Funafuti atoll, with negative local environmental consequences. Short-term scientific data show no evidence of SLR in Tuvalu, but the Government of Tuvalu has argued that there is visual evidence of SLR, through such consequences as increased erosion, flooding and salinity. Global media have increasingly emphasised a doomsday scenario, with Tuvalu as synecdoche and symbol of all threatened island environments. Environmental problems of diverse origin have been entirely attributed to distant processes causing SLR, in terms of ‘garbage can anarchy’ or a ‘conspiracy narrative’, and thus to distant causes. The Tuvalu Government has consequently sought compensation from, and migration opportunities in, distant states. The construction of apparently imminent hazard has potential domestic political and economic advantages, but environmental costs.

Mechanisms of Hypertension: The Expanding Role of Aldosterone

Hypertension is a common disorder that affects a large heterogeneous patient population. Subgroups can be identified on the basis of their responses to hormonal and biologic stimuli. These subgroups include low-renin hypertensives and nonmodulators. Aldosterone, the principal human mineralocorticoid, is increasingly recognized as playing a significant role in cardiovascular morbidity, and its role in hypertension has recently been reevaluated with studies that suggest that increased aldosterone biosynthesis (as defined by an elevated aldosterone to renin ratio) is a key phenotype in up to 15% of individuals with hypertension. It was reported previously that a polymorphism of the gene (C to T conversion at position -344) encoding aldosterone synthase is associated with hypertension, particularly in individuals with a high ratio. However, the most consistent association with this variant is a relative impairment of adrenal 11beta-hydroxylation. This review explores the evidence for this and provides a hypothesis linking impaired 11beta-hydroxylation and hypertension with a raised aldosterone to renin ratio. It is also speculated that there is substantial overlap between this group of patients and previously identified low-renin hypertensives and nonmodulators. Thus, these groups may form a neurohormonal spectrum reflecting different stages of hypertension or indeed form sequential steps in the natural history of hypertension in genetically susceptible individuals.

Music and Tourism: On the Road Again

Preface 1. Tourism and Music 2. Virtual Tourism 3. Musical Landscapes, Tourist Sites 4. Music in the Market: Economy, Society and Tourism 5. Music, Tourism and Culture: Authenticity and Identity 6. On The Road Again: Nostalgia and Pleasure 7. Festivals: Community and Capital 8. Conclusion: Final Notes

Chronic low-dose infusions of dexamethasone in rats: effects on blood pressure, body weight and plasma atrial natriuretic peptide.

Glucocorticoid-induced hypertension in rats has been studied using long-term, low-dose dexamethasone treatment. Dose-related increases in systolic blood pressure were achieved, without loss in body weight, with subcutaneous continuous infusions of 1, 2 and 5 micrograms dexamethasone per day, respectively, for 4 weeks. Rats treated with 10 micrograms dexamethasone per day lost weight at a rate of 10 g per week. Lower doses caused a significant reduction in weight gain compared with controls. Renin, aldosterone, plasma sodium and potassium concentrations were unaffected by dexamethasone treatment. Plasma atrial natriuretic peptide (ANP) concentrations were decreased by 40-50% by dexamethasone. These decreases were negatively correlated with increases in systolic blood pressure and haematocrit. Glucocorticoid-induced decreases in ANP contrast with ANP increases in response to mineralocorticoid treatment in rats with deoxycorticosterone-induced hypertension. Plasma concentrations of the endogenous glucocorticoid, corticosterone, were suppressed to the same very low levels by 5 and 10 micrograms dexamethasone per day; 1 and 2 micrograms doses were less effective. Unlike mineralocorticoid-induced hypertension, the pressor effects of dexamethasone were ameliorated but not abolished by dietary sodium restriction and were unaffected by sodium loading. Two micrograms of dexamethasone reduced plasma ANP in rats on either high- or low-sodium diets by 29 and 34%, respectively. We conclude that low-dose infusions (less than 5 micrograms/day) of dexamethasone are suitable for studying glucocorticoid-induced hypertension without the complications of weight loss that have been reported by others or of the mineralocorticoid-like side effects which endogenous glucocorticoids may exhibit.

Insulin-Mediated Vasodilation and Glucose Uptake Are Functionally Linked in Humans

Intra-arterial infusion of insulin in physiological doses causes forearm vasodilation which is augmented by co-infusion of D-glucose, leading us to speculate that local insulin-mediated vasodilation may depend on insulin-mediated glucose uptake. We have examined the relationship between whole-body insulin sensitivity and forearm vasodilation in response to local infusion of insulin/glucose, thus avoiding any confounding effects of sympathetic stimulation on peripheral blood flow. Eighteen healthy, normotensive male volunteers (age, 26+/-5.4 years) attended on two separate occasions for measurement of: (1) whole-body insulin sensitivity with use of the hyperinsulinemic euglycemic clamp; (2) forearm vasodilation in response to an intra-arterial infusion of insulin/glucose with use of bilateral venous occlusion plethysmography. Insulin-mediated glucose uptake (M) for the group (mean+/-SD) was 10.0+/-2.2 mg. kg-1. min-1, and the percentage change in forearm blood flow ratio (%FBFR) for the group (median, interquartile range) was 28.2% (13.6, 48.6). In univariate analysis, M was significantly correlated with %FBFR (rs=0.60, P<0.05), but not with body mass index (BMI) (rs=-0. 42), age (r=-0.39) or mean arterial pressure (r=0.13). In multiple regression analysis, %FBFR remained a significant independent predictor of M (R2 (adj)=0.48, t=3.23, P<0.01) in a model involving BMI, age, and blood pressure. These data support the concept of a significant functional relationship between insulins metabolic and vascular actions, possibly at an endothelial level.

Cultural Festivals and Economic Development in Nonmetropolitan Australia

Examining a database of 2,856 festivals in Australia and survey results from 480 festival organizers, we consider how nonmetropolitan cultural festivals provide constraints as well as opportunities for economic planners. Cultural festivals are ubiquitous, impressively diverse, and strongly connected to local communities through employment, volunteerism, and participation. Despite cultural festivals being mostly small-scale, economically modest affairs, geared around community goals, the regional proliferation of cultural festivals produces enormous direct and indirect economic benefits. Amidst debates over cultural and political issues (such as identity, exclusion, and elitism), links between cultural festivals and economic development planning are explored.

Migration and Remittances in the South Pacific: Towards New Perspectives

For more than a quarter of a century there has been substantial emigration from the smaller island states of the Pacific to metropolitan fringe states, mainly the United States, New Zealand and Australia. Migration reduced unemployment in the island states and remittances have contributed to raised living standards. There has been some shift of remittances from consumption to investment. Communal remittances are of greater significance than in other world regions. There is a high propensity to sustain remittance flows over long periods of time at some cost to the senders. The duration and magnitude of migration, the remittance flows and their considerable social and economic consequences in a range of contexts has demonstrated the need for much more attention to be given, in terms of both studies and policy formation, to the role of migration and remittances in economic and social development in the Pacific region.

Nauru: The first failed Pacific State?

Abstract In recent years supposedly ‘failed states’ have been recognized in the Pacific. Nauru, once rich, has acquired most of the characteristics of a failed state, in large part because of the consequences of an extreme ‘resource curse’ scenario, where other economic sectors fail. Mining of phosphate is now almost over. Wasteful expenditure, especially on a national airline and the panoply of a ‘welfare state’, and inadequate health services and education systems created budget deficits but not the skills required to develop an alternative economy to mining. The collapse of a corrupt offshore banking and passport system emphasized this failure. Political systems have been too inexperienced, short-term and divided to stabilize the political economy. Regional external intervention has occurred and may lead to extensive emigration from Nauru and to a new political status.

Hillsong: A Megachurch in the Sydney Suburbs

Abstract Religious belief and practice, especially Pentecostalism, are increasingly suburban phenomena in an otherwise more secular society. The megachurch of Hillsong in Sydneys north-western suburbs has recently grown rapidly, offering a distinct architecture, institutional structure and informal service format Protestantism generally, distinguished by its stadium show, prosperity preaching, overt materialist orientation and egalitarian populism. Diverse church social groups have partly replaced the civic social institutions never vibrant in suburbia, creating social capital and a new, more fluid sense of place. Hillsong exemplifies the globalisation of religion, while simultaneously stressing local ties, with contemporary media technology in a traditional theological and modern social context.

Candoxatril, an orally active neutral endopeptidase inhibitor, raises plasma atrial natriuretic factor and is natriuretic in essential hypertension

Objective: Candoxatril (UK 79,300) is an orally available inhibitor of the neutral endopeptidase (E.C.3.4.24.11) which degrades atrial natriuretic factor (ANF). This study was designed to establish initial safety and efficacy data in essential hypertension for this novel class of drug. Design: A prospective, double-blind, placebo-controlled, single-dose comparison of candoxatril with placebo in a crossover manner. Three doses of candoxatril (10, 50 and 200 mg) were used, with four subjects at each dose level. Setting: The Medical Research Council Blood Pressure Unit, Western Infirmary, Glasgow, UK (a hospital clinical research unit). Patients: Twelve patients with untreated essential hypertension. Diastolic blood pressure was >95 mmHg on three separate occasions before entry to the study. Intervention: Candoxatril or matching placebo was administered orally in the fasting state. Serial measurements of urinary volume and electrolyte excretion were taken (on each hour, urine volume was replaced with an equivalent volume of water by mouth). Blood pressure and heart rate were recorded for 12 h after drug administration and serial blood samples were taken for measurement of plasma ANF and neurohormone concentrations. Main outcome measures: Urine volume and electrolyte concentration; blood pressure; heart rate; plasma atrial natriuretic factor. Results: Plasma ANF concentrations rose significantly in all patients within 2 h of candoxatril administration compared with placebo although peak and integrated ANF levels were similar at all three doses. A significant natriuresis was only seen after 200 mg candoxatril, with a greater cumulative urine sodium excretion over 12 h compared with placebo; this was associated with a greater diuresis over 12 h compared with placebo. After a single oral dose of candoxatril, blood pressure and heart rate remained unchanged. Conclusions: Candoxatril in a single dose caused no adverse effects in essential hypertension. The drug caused a rise in basal ANF levels at all doses, but natriuresis was only seen with the highest dose used. No change in blood pressure was recorded after acute dosing and the results of chronic studies with this compound are awaited. Oral inhibitors of ANF degradation may have therapeutic potential in cardiovascular disorders.