Eutrophication has no short-term effect on the Cymbastela stipitata holobiont

Levels of nitrogen in coastal areas have been rapidly increasing due to accumulative inputs of sewage and terrigenous sediments carrying fertilizers. Sponges have an immense filtering capacity and may be directly impacted (positively or negatively) by elevated concentrations of nitrogen. Sponges also host a wide diversity of microbes involved in nitrogen metabolism, yet little is known about the effects of nitrogen loading on these symbiotic partnerships. Manipulative experiments were undertaken to examine the potential effects of excess nitrogen (up to 240 μM) on microbial symbiosis in the abundant sponge species Cymbastela stipitata. Microbial composition and activity were examined using 454-pyrotag sequencing of DNA- and RNA-derived samples. Despite the high levels of nitrogen exposure (up to 124-fold above ambient), sponges appeared visibly unaffected at all treatment concentrations. At the phylum level, the microbial community was consistent between all sponge samples regardless of nitrogen treatment, with Cyanobacteria and Thaumarchaeota being the dominant taxa. Higher microbial diversity was observed at the operational taxonomic units (OTU) level (97% sequence similarity), with only 40% of OTUs shared between samples from all treatments. However, a single cyanobacterial OTU dominated the community of all individuals (average 73.5%) and this OTU did not vary with nitrogen treatment. The conserved microbial community in all sponges irrespective of nitrogen treatment highlights the stability of the sponge-microbe relationship and indicates that the holobiont is resistant to short pulses of nitrogen at levels mimicking sewage effluent

Phytoplasmas in Australian grapevines - detection, differentiation and associated diseases

Phytoplasmas associated with Australian grapevine yellows (AGY) symptoms were detected using the polymerase chain reaction (PCR). To optimise the diagnostic, nested PCRs were compared with single PCRs using different primer pairs. Grapevine DNA known to be AGY phytoplasma positive was serially diluted and subjected to nested and single round PCR tests to determine which was the most sensitive. Samples taken over two growing seasons were used to determine the optimum sampling time for phytoplasma detection. The specificity of primer pairs was determined using phytoplasmas detected in Australian grapevines and overseas reference grapevine phytoplasmas. DNA extracted from grapevine exhibiting a range of symptoms was screened for phytoplasmas. Two different phytoplasmas were amplified in the PCR and they were identified using specific PCR primers and by restriction fragment length polymorphism (RFLP) analysis of the 16S rRNA gene and 16S rRNA/23S rRNA spacer region. RFLP analysis confirmed that one phytoplasma was the AGY phytoplasma and the other phytoplasma was indistinguishable from the tomato big bud (TBB) phytoplasma. The AGY phytoplasma was associated with AGY symptoms but was occasionally detected in asymptomatic vines and those with late season leaf curl (LSLC) and restricted growth (RG) symptoms. The TBB phytoplasma was detected in some vines with LSLC symptoms and very occasionally in vines with AGY symptoms. A 'variant' of the AGY phytoplasma was also detected in vines showing typical AGY symptoms

Multiple approaches to microbial source tracking in tropical northern Australia

© The Author(s), 2014. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in MicrobiologyOpen 3 (2014): 860–874, doi:10.1002/mbo3.209.Microbial source tracking is an area of research in which multiple approaches are used to identify the sources of elevated bacterial concentrations in recreational lakes and beaches. At our study location in Darwin, northern Australia, water quality in the harbor is generally good, however dry-season beach closures due to elevated Escherichia coli and enterococci counts are a cause for concern. The sources of these high bacteria counts are currently unknown. To address this, we sampled sewage outfalls, other potential inputs, such as urban rivers and drains, and surrounding beaches, and used genetic fingerprints from E. coli and enterococci communities, fecal markers and 454 pyrosequencing to track contamination sources. A sewage effluent outfall (Larrakeyah discharge) was a source of bacteria, including fecal bacteria that impacted nearby beaches. Two other treated effluent discharges did not appear to influence sites other than those directly adjacent. Several beaches contained fecal indicator bacteria that likely originated from urban rivers and creeks within the catchment. Generally, connectivity between the sites was observed within distinct geographical locations and it appeared that most of the bacterial contamination on Darwin beaches was confined to local sources

Skin bacterial diversity is higher on lizards than sympatric frogs in tropical Australia

Animal skin acts as a barrier between the organism and its environment and provides the first line of defense against invading pathogens. Thus, skin surfaces harbor communities of microbes that are interacting with both the host and its environment. Amphibian skin bacteria form distinct communities closely tied to their host species, but few studies have compared bacterial communities between amphibians and other, non-amphibian sympatric animals. Notably, skin microbes on reptiles have gained little attention. We used next-generation sequencing technology to describe bacterial communities on the skin of three lizard species and compared them to bacteria on six cohabiting frog species in the Northern Territory of Australia. We found bacterial communities had higher richness and diversity on lizards than frogs, with different community composition between reptiles and amphibians and among species. Core bacteria on the three lizard species overlapped by over 100 operational taxonomic units. The bacterial communities were similar within species of frogs and lizards, but the communities tended to be more similar between lizard species than between frog species and when comparing lizards with frogs. The diverse bacteria found on lizards invites further questions on how and how well reptiles interact with microorganisms through their scaly skin

Loughborough University SKInS: wearable simulations of occupational health – defining specifications and product development

A previous paper presented at CIB W099 2009 reported the authors’ aim to develop wearable devices to simulate occupational health effects, and their consequential impacts on both working and home life, as experienced by older construction workers. The rationale for the research is that, when worn, the Loughborough University SKInS (Sensory and Kinaesthetic Interactive Simulations) will enable younger workers to directly experience age-related occupational ill-health conditions and so encourage behavioural change and improve future occupational health. Furthermore, other industry stakeholders (managers, architects, equipment designers, etc) should be able to better appreciate the challenges faced by older workers and, through this improved awareness, contribute to an attitude-shift to occupational health within the industry. This paper describes the progress of the project in defining the specifications for five given health conditions that are frequently encountered in construction. The specifications were defined at mild, moderate and severe levels thereby enabling wearers to appreciate the progression of the conditions and their resultant impacts at each stage. The paper further describes how the Loughborough University SKInS were then developed to meet these specifications and discusses the limiting factors which shaped the ultimate designs. Initial reviews by health professionals and industry representatives regarding their fidelity and potential contribution to the industry are also presented

Reproductive Health Supplies in Six Countries: Themes and Entry Points in Policies, Systems and Funding in Bangladesh, Ghana, Mexico, Nicaragua, Tanzania, and Uganda.

Reproductive Health Supplies in Six Countries: Themes and Entry Points in Policies, Systems and Funding, identifies the challenges faced by reproductive health programs in Bangladesh, Ghana, Mexico, Nicaragua, Tanzania, and Uganda. Funding constraints, combined with a weak commitment to prioritize the purchase of reproductive health supplies on the side of the recipient countries and a limited capacity for distribution, have created an unstable environment for supplies worldwide. The report, and its six associated case studies, calls for renewed attention to reproductive health supplies to avoid putting the health of millions of women at risk