Space radiation measurements during the Artemis I lunar mission.

Space radiation is a notable hazard for long-duration human spaceflight. Associated risks include cancer, cataracts, degenerative diseases and tissue reactions from large, acute exposures. Space radiation originates from diverse sources, including galactic cosmic rays, trapped-particle (Van Allen) belts and solar-particle events.

Estimating risk associated with human norovirus and hepatitis A virus in fresh Australian leafy greens and berries at retail.

The apparent international rise in foodborne virus outbreaks attributed to fresh produce and the increasing importance of fresh produce in the Australian diet has led to the requirement to gather information to inform the development of risk management strategies. A prevalence survey for norovirus (NoV) and hepatitis A virus (HAV) in fresh Australian produce (leafy greens, strawberries and blueberries) at retail was undertaken during 2013-2014 and data used to develop a risk profile. The prevalence of HAV in berries and leafy greens was estimated to be <2%, with no virus detected in produce during the yearlong survey.

Experimental uptake and depuration of paralytic shellfish toxins in Southern Rock Lobster, Jasus edwardsii.

In October 2012, paralytic shellfish toxins (PST) were detected in the hepatopancreas of Southern Rock Lobsters (Jasus edwardsii) collected from the east coast of Tasmania, Australia. This resulted in the first commercial closure in Australia for this species. Questions were raised on how the toxins were transferred to the lobsters, how long the toxins would persist, whether PST-contaminated hepatopancreas posed a risk to human health, and what management strategies could be applied.

National survey of foodborne viruses in Australian oysters at production.

Internationally human enteric viruses, such as norovirus (NoV) and hepatitis A virus (HAV), are frequently associated with shellfish related foodborne disease outbreaks, and it has been suggested that acceptable NoV limits based on end-point testing be established for this high risk food group. Currently, shellfish safety is generally managed through the use of indicators of faecal contamination. Between July 2014 and August 2015, a national prevalence survey for NoV and HAV was done in Australian oysters suitable for harvest.

Spatial and Temporal Distribution of Norovirus and E. coli in Sydney Rock Oysters Following a Sewage Overflow into an Estuary.

This paper reports a study of norovirus (NoV) GII distribution and persistence in Sydney rock oysters (SRO) (Saccostrea glomerata) located in an estuary after a pump station sewage overflow. SRO were strategically placed at six sites spanning the length of the estuary from the pump station to the sea. The spatial and temporal distribution of NoV, hepatitis A virus (HAV) and Escherichia coli (E.

Depuration and Relaying: A Review on Potential Removal of Norovirus from Oysters.

Pollution of coastal waters can result in contamination of bivalve shellfish with human enteric viruses, including norovirus (NoV), and oysters are commonly implicated in outbreaks. Depuration is a postharvest treatment involving placement of shellfish in tanks of clean seawater to reduce contaminant levels; this review focuses on the efficacy of depuration in reducing NoV in oysters. There have been many NoV outbreaks from depurated oysters containing around 10 genome copies/g oyster tissue, far exceeding the median infectious dose (ID50).

Digital PCR for Quantifying Norovirus in Oysters Implicated in Outbreaks, France.

Using samples from oysters clearly implicated in human disease, we quantified norovirus levels by using digital PCR. Concentrations varied from 43 to 1,170 RNA copies/oyster. The analysis of frozen samples from the production area showed the presence of norovirus 2 weeks before consumption.

Australian seafood compositional profiles: A pilot study. Vitamin D and mercury content.

Given the scarcity of comprehensive nutritional data for Australia's >400 commercially produced seafood species a pilot study was undertaken to collect and analyse 22 species of wild and aquaculture seafood in order to develop a model for future comprehensive surveys. The species analysed were: Atlantic salmon, Australian sardine, prawn (six species), barramundi, abalone (three species), blue sprat, burrowing blackfish, gummy shark, oyster (four species), ocean trout and yellowtail kingfish. The analyses undertaken in this pilot study were: moisture, protein, total fat, cholesterol, fatty acids, vitamin C, vitamins A and D, and 21 mineral elements (including total mercury and methyl mercury).

An outbreak of norovirus genogroup II associated with New South Wales oysters.

Introduction: Currently available antigen tests for norovirus (NoV) have excellent specificity but negative results do not always rule out infection. Real-time reverse transcription polymerase chain reaction (RT-PCR) is a useful method for detecting and genotyping NoV in humans and oysters. An outbreak of NoV associated with oyster consumption in northern New South Wales confirmed the value of real-time RT-PCR where immunochromatography (ICT) tests were negative.

A national survey of marine biotoxins in wild-caught abalone in Australia.

The first national survey of Australian wild-caught abalone was conducted between September 2012 and December 2013. The aim of the survey was to determine the presence of paralytic shellfish toxins (PSTs), amnesic shellfish toxins (ASTs), and diarrhetic shellfish toxins (DSTs) in wild-caught abalone at levels above the current Codex marine biotoxin limits during the 2013 fishing season. Abalone (n = 190) were collected from 68 abalone-fishing blocks for which the combined annual harvest accounts for 80 % of Australian production.

Paralytic shellfish toxins, including deoxydecarbamoyl-STX, in wild-caught Tasmanian abalone (Haliotis rubra).

For the first time wild-caught Tasmanian abalone, Haliotis rubra, have been reported to contain paralytic shellfish toxins (PSTs). This observation followed blooms of the toxic dinoflagellate Gymnodinium catenatum. No illnesses were reported, but harvesting restrictions were enforced in commercial areas.

A survey of Australian oysters for the presence of human noroviruses.

Impending international policies for norovirus in oysters and the lack of Australian data suggested there was a need to undertake a national survey of norovirus in oysters. Two geographically distinct oyster-growing areas from each of three Australian states were sampled on 4 occasions during 2010 and 2011. The sites selected were considered by state shellfish authorities to be the most compromised with respect to the potential for human faecal contamination as identified by shoreline surveys.

The laboratory mouse in routine food safety testing for marine algal biotoxins and harmful algal bloom toxin research: past, present and future.

Mouse bioassays have been a mainstay for detecting harmful concentrations of marine algal toxins in shellfish for over 70 years. Routine monitoring involves intraperitoneal injection of shellfish extracts into mice; shellfish contaminated with algal toxins are thus identified by mortality in exposed mice. With the advent of alternative test methods to detect and quantify specific algal toxins has come increasing criticism of enduring use of mouse bioassays for shellfish safety testing.

Theoretical dietary modelling of Australian seafood species to meet long-chain omega 3 fatty acid dietary recommendations.

Background: Several agencies recommend seafood to be consumed 2-3 times per week. In Australia, there is a lack of nutrient composition data for seafood species and it is not known whether including different seafood species in a diet would provide sufficient long-chain omega 3 fatty acids (LC n-3 PUFA) to meet various national recommendations.

Objective: To utilise recent nutrient composition data for major Australian seafood groups (n=24) with the addition of two tuna options (total n=26) to: (1) determine whether including these species into a diet based on the Australian Guide to Healthy Eating (AGHE) will achieve LC n-3 PUFA recommendations [Adequate Intake (AI: 160 mg/d men, 90 mg/d women)], Suggested Dietary Target (SDT), 500 mg/d Heart Foundation (HF) recommendation and (2) determine the weekly number of servings of seafood to meet recommendations using either lower fat (n=23, <10% total fat) or higher fat (n=3, ≥10% total fat) seafood.

Comparative toxicity of polyglutamine, polyalanine and polyleucine tracts in Drosophila models of expanded repeat disease.

Homopolymeric amino acid repeat sequences in proteins are of particular interest due to the discovery that expanded copy numbers of these repeats are the molecular basis for a growing list of human genetic diseases. Repeat copy numbers above a typical normal range of polyglutamine repeats have been found to be the principal pathogenic agents in a number of these diseases, including Huntington's disease. There is emerging evidence that expansions of amino acids encoded by other reading frames of CAG/CUG repeats, including polyalanine and polyleucine, could contribute to toxicity in the 'polyglutamine' diseases.

Regulation of adult stem cell behavior by nutrient signaling.

Adult stem cells play an essential role throughout life, maintaining tissue and organ function by providing a reservoir of cells for homeostasis and repair. Maintenance and activity of adult stem cells have been the focus of numerous studies that have revealed stem cell-intrinsic factors and signals from the local microenvironment that regulate stem cell behavior. A growing body of work has provided evidence that circulating, systemic factors also contribute to the regulation of stem cell behavior in numerous tissues.

Double-stranded RNA is pathogenic in Drosophila models of expanded repeat neurodegenerative diseases.

The pathogenic agent responsible for the expanded repeat diseases, a group of neurodegenerative diseases that includes Huntington's disease is not yet fully understood. Expanded polyglutamine (polyQ) is thought to be the toxic agent in certain cases, however, not all expanded repeat disease genes can encode a polyQ sequence. Since a repeat-containing RNA intermediary is common to all of these diseases, hairpin-forming single-stranded RNA has been investigated as a potential common pathogenic agent.

Uptake, distribution and depuration of paralytic shellfish toxins from Alexandrium minutum in Australian greenlip abalone, Haliotis laevigata.

Farmed greenlip abalone Haliotis laevigata were fed commercial seaweed-based food pellets or feed pellets supplemented with 8 × 10⁵ Alexandrium minutum dinoflagellate cells g⁻¹ (containing 12 ± 3.0 μg STX-equivalent 100 g⁻¹, which was mainly GTX-1,4) every second day for 50 days. Exposure of abalone to PST supplemented feed for 50 days did not affect behaviour or survival but saw accumulation of up to 1.

Perturbation of the Akt/Gsk3-β signalling pathway is common to Drosophila expressing expanded untranslated CAG, CUG and AUUCU repeat RNAs.

Recent evidence supports a role for RNA as a common pathogenic agent in both the 'polyglutamine' and 'untranslated' dominant expanded repeat disorders. One feature of all repeat sequences currently associated with disease is their predicted ability to form a hairpin secondary structure at the RNA level. In order to investigate mechanisms by which hairpin-forming repeat RNAs could induce neurodegeneration, we have looked for alterations in gene transcript levels as hallmarks of the cellular response to toxic hairpin repeat RNAs.

Esthetics and smile characteristics evaluated by laypersons.

Objective: To collect data regarding Canadian laypersons' perceptions of smile esthetics and compare these data to US data in order to evaluate cultural differences.

Materials And Methods: Using Adobe Photoshop 7, a digital image of a posed smile of a sexually ambiguous lower face was prepared so that hard and soft tissue could be manipulated to alter buccal corridor (BC), gingival display (GD), occlusal cant (OC), maxillary midline to face discrepancy (MMFD), and lateral central gingival discrepancy (LCGD). Adult Canadian laypersons (n  =  103) completed an interactive computer-based survey of 29 randomized images to compare smile preferences for these variables.

Stem cell dynamics in response to nutrient availability.

When nutrient availability becomes limited, animals must actively adjust their metabolism to allocate limited resources and maintain tissue homeostasis. However, it is poorly understood how tissues maintained by adult stem cells respond to chronic changes in metabolism. To begin to address this question, we fed flies a diet lacking protein (protein starvation) and assayed both germline and intestinal stem cells.

Dietary restriction enhances germline stem cell maintenance.

Dietary restriction (DR) increases lifespan in species ranging from yeast to primates, maintaining tissues in a youthful state and delaying reproductive senescence. However, little is known about the mechanisms by which this occurs. Here we demonstrate that, concurrent with extending lifespan, DR attenuates the age-related decline in male germline stem cell (GSC) number in Drosophila.

Differences in macro- and microarchitecture of the appendicular skeleton in young Chinese and white women.

To identify the racial differences in macro- and microstructure of the distal radius and tibia that may account for the lower fracture rates in Asians than whites, we studied 61 healthy premenopausal Chinese and 111 white women 18-45 yr of age using high-resolution pQCT (HR-pQCT). The Chinese were shorter and leaner. Distal radius total cross-sectional area (CSA) was 14.

Canine eruption in patients with complete cleft lip and palate.

Objective: To describe erupting maxillary canine positions in patients with bone-grafted alveolar clefts.

Sample: The sample consisted of 101 cleft sites from patients with complete unilateral or bilateral cleft lip and palate who had early (< or =9 years) or late (>9 years) secondary alveolar bone grafts.

Methods: Canine position was assessed using panoramic radiographs taken before and after alveolar bone grafts.