Cause of Cambrian Explosion - Terrestrial or Cosmic?

We review the salient evidence consistent with or predicted by the Hoyle-Wickramasinghe (H-W) thesis of Cometary (Cosmic) Biology. Much of this physical and biological evidence is multifactorial. One particular focus are the recent studies which date the emergence of the complex retroviruses of vertebrate lines at or just before the Cambrian Explosion of ∼500 Ma. Such viruses are known to be plausibly associated with major evolutionary genomic processes. We believe this coincidence is not fortuitous but is consistent with a key prediction of H-W theory whereby major extinction-diversification evolutionary boundaries coincide with virus-bearing cometary-bolide bombardment events. A second focus is the remarkable evolution of intelligent complexity (Cephalopods) culminating in the emergence of the Octopus. A third focus concerns the micro-organism fossil evidence contained within meteorites as well as the detection in the upper atmosphere of apparent incoming life-bearing particles from space. In our view the totality of the multifactorial data and critical analyses assembled by Fred Hoyle, Chandra Wickramasinghe and their many colleagues since the 1960s leads to a very plausible conclusion - life may have been seeded here on Earth by life-bearing comets as soon as conditions on Earth allowed it to flourish (about or just before 4.1 Billion years ago); and living organisms such as space-resistant and space-hardy bacteria, viruses, more complex eukaryotic cells, fertilised ova and seeds have been continuously delivered ever since to Earth so being one important driver of further terrestrial evolution which has resulted in considerable genetic diversity and which has led to the emergence of mankind.

The Florey turns 50.

The origins of the Howard Florey Laboratories of Experimental Physiology, Department of Physiology, The University of Melbourne, are tied to the ground-breaking clinical work of Derek A Denton in 1947 and to the investigations of the initial scientific team into the control of salt and water balance in health and disease over the period 1947-1963 were Professor RD Wright, Drs JR Goding, IR McDonald, John P Coghlan, E Marelyn Wintour and John R Blair-West. An Act of Parliament in 1971 by the Victorian State Government formally established the Institute named after Howard Florey, the Australian Nobel Prize winner who isolated penicillin. The Howard Florey Laboratories/Institute quickly became an international leader in the scientific areas of the physiological control of body fluids and electrolyte balance, especially sodium regulation and the regulation of the secretion of aldosterone, the adrenal salt-retaining hormone; the micro measurement of hormones, in particular steroids and peptides; instinctive ingestive behaviour; fetal fluid regulation; hybridization histochemistry, and the hormone relaxin. Subsequently, the senior staff included, inter alia, Bruce Scoggins, Richard Weisinger, John McDougall, Brian Oldfield, Michael McKinley, Robin McAllen, Hugh Niall, Geoff Tregear and Felix Beck. During the 1990s, an explosion occurred in neuroscience and, in 1997, the Board made the strategic decision to change the focus of the Institute to brain disorders. From 1997 to 2007, Fred Mendelsohn steered the Florey to become one of Australia's premier brain research institutes and, under the current director (the eminent clinician and neuroscientist Geoffrey Donnan), this reputation has been further enhanced.

Expanding view of aldosterone action, with an emphasis on rapid action.

1. The actions of aldosterone beyond the 'mineralocorticoid' designation continue to attract intense interest. In recent years, two aspects have received particular attention. These are, first, the potentially damaging direct actions of aldosterone on the heart and vascular system, and the clear benefit, as illustrated by the Randomized Aldactone Evaluation Study and Eplerenone Post-Acute Myocardial Infarction Heart Failure Efficacy and Survival trials, of including antialdosterone therapy in the treatment of cardiovascular disease. 2. Second, the importance of non-genomic actions of aldosterone has become clear, some of which might possibly be mediated by distinct membrane receptors. Over the past 5 years, evidence has arisen to bring these two aspects together, and now emphasizes the role of rapid, nongenomic actions of aldosterone on cardiovascular events. 3. However, despite many years of study, there is still no clear view of the nature of the receptors mediating non-genomic responses. We examine the evidence, and suggest that in many cases non-genomic actions are attributable to classical mineralocorticoid receptors.

The discovery, isolation and identification of aldosterone: reflections on emerging regulation and function.

This paper has a focus on the early history of aldosterone. The Taits take us on a chronological trawl through the history in which they had a first hand role and made a major contribution-their bioassay was in many ways the key. The gifted Swiss chemists made a critical contribution to the scale and isolation of larger amounts. This was international collaboration at its best. Developing technologies were utilised as crucial cutting edge applications in the advancing front, technology transfer before the word was invented. Measurement of aldosterone and angiotensin were crucial advances to the understanding of the regulation of the hormone. In the period 1960-2003, some 30,000 papers mentioned aldosterone as a keyword, even so advances on a larger scale were slow. I have indicated some of my own work with the Howard Florey team using the adrenal autotransplant in the conscious sheep. Recently, the understanding of the role of induced proteins, the flow on from the RALES trial and the development of eplerenone has revitalised the aldosterone field.