Mosquito isolates of Ross River virus from Cairns, Queensland, Australia

During 1996-1998 60,619 mosquitoes were collected around Cairns, Australia and processed for Alphavirus isolation. Thirty-three isolates of Ross River (RR) virus were made from 9 species, Aedes imprimens, Aedes kochi, Aedes notoscriptus, Aedes vigilax, Culex annulirostris, Culex gelidus, Mansonia septempunctata, Verrallina (formerly Aedes) carmenti, and Verrallina lineatus. Attempts to isolate RR virus from 121 Aedes aegypti were unsuccessful. Twenty six (79%) of the isolates came from within 1 km of a colony of spectacled flying-foxes, Pteropus conspicillatus. The minimum infection rate for these mosquitoes was 1.0 compared with 0.2 per 1,000 for mosquitoes trapped at all other sites. Ross River virus has not previously been isolated from Ae. imprimens, Cx. gelidus, Ma. septempunctata, Ve. carmenti, or Ve. lineatus. This is also the first isolation of an arbovirus from Cx. gelidus in Australia. In conclusion, the vector status of Ve. carmenti, Ae. aegypti and Mn. septempunctata warrants further study. This study also provides evidence that P. conspicillatus may be a reservoir host.

Ultrastructure and small-subunit ribosomal DNA sequence of Henneguya lesteri n. sp (Myxosporea), a parasite of sand whiting Sillago analis (Sillaginidae) from the coast of Queensland, Australia

Henneguya lesteri n. sp, (Myxosporea) is described from sand whiting, Sillago analis, from the southern Queensland coast of Australia. H. lesteri displays a preference for the pseudobranchs and is typically positioned along the afferent blood vessels, displacing the adjoining lamellae and disrupting their normal array, The plasmodia appeared as whitish-hyaline, elliptical cysts (mean dimensions 230 x 410 mum) attached to the oral mucosa lining of the hyoid arch on the inner surface of the operculum. Infections of the gills were also found, in which the plasmodia were spherical, averaged 240 x 240 mum in size and were located on the inner hemibranch margin. The parasites lodged in the gill filament crypts and generated a mild hyperplastic response of the branchial epithelium, In histological sections, the plasmodium wall and adjoining ectoplasm appeared as a finely granulated, weakly eosinophilic layer, Ultrastructurally, this section of the host-parasite interface contained an intricate complex of pinocytotic channels. H. lesteri is polysporic, disporoblastic and pansporoblast forming. Sporogenesis is asynchronous, with the earliest developmental stages aligned predominantly along the plasmodium periphery, and maturing sporoblasts and spores toward the center. Ultrastructural details of sporoblast and spore development are in agreement with previously described myxosporeans. The mature spore is drop-shaped, length (mean) 9.1 mum, width 4.7 mum, thickness 2.5 mum, and comprises 2 polar capsules positioned closely together, a binucleated sporoplasm and a caudal process of 12.6 mum. The polar capsules are elongated, 3.2 x 1.6 mum, with 4 turns of the polar filament. Mean length of the everted filament is 23.2 mum, Few studies have analyzed the 18S gene-of marine Myxosporea. In fact, H. lesteri is the first marine species of Henneguya to be characterized at the molecular level: we determined 1966 bp of the small-subunit (18S) rDNA, The results indicated that differences between this and the hitherto studied freshwater Henneguya species are greater than differences among the freshwater Henneguya species.

Geographic variation of notified Ross River virus infections in Queensland, Australia, 1985-1996

The spatial and temporal variations of Ross River virus infections reported in Queensland, Australia, between 1985 and 1996 were studied by using the Geographic Information System. The notified cases of Ross River virus infection came from 489 localities between 1985 and 1988, 805 between 1989 and 1992, and 1,157 between 1993 and 1996 (X (2)((df = 2)) = 680.9; P < 0.001). There was a marked increase in the number of localities where the cases were reported by 65 percent for the period of 1989-1992 and 137 percent for 1993-1996, compared with that for 1985-1988. The geographic distribution of the notified Ross River virus cases has expanded in Queensland over recent years. As Ross River virus disease has impacted considerably on tourism and industry, as well as on residents of affected areas, more research is required to explore the causes of the geographic expansion of the notified Ross River virus infections.

Depositional environments for strata cored in CRP-3 (Cape Roberts Project), Victoria Land Basin, Antarctica: palaeoglaciological and palaeoclimatological inferences

Cape Roberts Project drill core 3 (CRP-3) was obtained from Roberts ridge, a sea-floor high located at 77°S, 12 km offshore from Cape Roberts in western McMurdo Sound, Antarctica. The recovered core is about 939 m long and comprises strata dated as being early Oligocene (possibly latest Eocene) in age, resting unconformably on ∼ 116 m of basement rocks consisting of Palaeozoic Beacon Supergroup sediments. The core includes ten facies commonly occuring in five major associations that are repeated in particular sequences throughout the core and which are interpreted as representing different depositional environments through time. Depositional systems inferred to be represented in the succession include: outer shelf, inner shelf, nearshore to shoreface each under iceberg influence, deltaic and/or grounding-line fan, and ice proximal-ice marginal-subglacial (mass flow/rainout diamictite/subglacial till) singly or in combination. The record is taken to represent the initial talus/alluvial fan setting of a glaciated rift margin adjacent to the block-uplifted Transantarctic Mountains. Development of a deltaic succession upcore was probably associated with the formation of palaeo-Mackay valley with temperate glaciers in its headwaters. At that stage glaciation was intense enough to support glaciers ending in the sea elsewhere along the coast, but a local glacier was fluctuating down to the sea by the time the youngest part of CRP-3 was being deposited. Changes in palaeoenvironmental interpretations in this youngest part of the core are used to estimate relative glacial proximity to the drillsite through time. These inferred glacial fluctuations are compared with the global δ18O and Mg/Ca curves to evaluate the potential of glacial fluctuations on Antarctica for influencing these records of global change. Although the comparisons are tentative at present, the records do have similarities, but there are also some differences that require further evaluation.

Euzetia occultum n. g., n. sp (Euzetiinae n. subf.), a monocotylid monogenean from the gills of Rhinoptera neglecta (Rhinopteridae) from Moreton Bay, Queensland, Australia

Euzetia occultum n. g., n. sp. (Monogenea: Monocotylidae) is described from the gills of the Australian cownose ray Rhinoptera neglecta Ogilby collected in Moreton Bay, Queensland, Australia. Euzetia has one central and ten peripheral loculi, which is similar to species in Decacotyle Young, 1967. However Euzetia is distinguished from other genera in the family by the presence of an additional loculus on either side of the central loculus. Because Euzetia does not fit into any of the six existing subfamilies in the Monocotylidae Taschenberg, 1879, as currently recognised, we propose the Euzetiinae n. subf. to accommodate the new genus. Euzetia occultum is described and illustrated fully. This is the first published record of a monocotylid from a species of Rhinoptera Cuvier.

The impact of the Human Genome Project on medical genetics

The near completion of the Human Genome Project stands as a remarkable achievement, with enormous implications for both science and society. For scientists, it is the first step in a complex process that will lead to important advances in the diagnosis and treatment of many diseases. Society, meanwhile, must prevent genetic discrimination, and protect genetic privacy through appropriate legislation.

Use of the web to provide learning support for a large metabolism and nutrition class

To support student learning in a large Metabolism and Nutrition class, we have introduced a web-based package, using a commercially available program, WebCT. The package was developed at a minimal cost and with limited resources. In addition to downloadable (PDF) versions of lecture Powerpoint presentations, tutorial outlines and a practical class exercise, web-based self-directed learning exercises were included to reinforce and extend lecture material in an active learning environment. The web-site also contained a variety of formative and summative assessment tasks that examined both factual recall and higher order thinking Detailed course information, timetables and a bulletin board were also readily accessible. Student usage of the site was generally high, but varied widely between individual students. Students who achieved a high overall score for the course completed on average three times as many formative assessment items and achieved a higher score for all tests than students who did poorly. Student feedback about the site was very positive with the majority of students reporting that the course material and assessment items that were available were useful to their learning. Administration of the course was also facilitated. (C) 2001 IUBMB. Published by Elsevier Science Ltd. All rights reserved.

Childhood poisoning in Queensland: An analysis of presentation and admission rates

Objective: To determine the presentation rates for paediatric poisoning by ingestion and the determinants of hospital admission. Methodology: Cross-sectional survey using an injury surveillance database from emergency departments in South Brisbane, Mackay and Mt Isa, Queensland, from January 1998 to December 1999. There were 1516 children aged 0-14 years who presented following ingestional poisoning. Results: The presentation rates for poisoning were 690, 40 and 67 per 100 000 population aged 0-4, 5-9 and 10-14 years, respectively. The admission rates to hospital for poisoning were 144, 14 and 22 per 100 000 population aged 0-4, 5-9 and 10-14 years, respectively. Although presentation rates for poisoning were higher in the rural centres the admission rates were disproportionately high for the 0-4 years age group. The agents most frequently ingested were paracetamol, Dimetapp(R), rodenticides and essential oils. Conclusion: There is a need to design and implement interventions aimed at reducing poison exposures and unnecessary hospital admissions in the 0-4 years age group.