Differential expression of genes involved in iron metabolism in Aspergillus fumigatus

The ability of fungi to survive in many environments is linked to their capacity to acquire essential nutrients. Iron is generally complexed and available in very limited amounts. Like bacteria, fungi have evolved highly specific systems for iron acquisition. Production and uptake of iron-chelating siderophores has been shown to be important for certain human bacterial pathogens, as well as in fungal pathogens such as Cryptococcus neoformans and Fusarium graminearum. This system also enables the opportunistic fungal pathogen Aspergillus fumigatus to infect and subsequently colonize the human lung. In this study, advantage was taken of genome sequence data available for both Aspergillus nidulans and A. fumigatus either to partially clone or to design PCR primers for 10 genes putatively involved in siderophore biosynthesis or uptake in A. fumigatus. The expression of these genes was then monitored by semi-quantitative and quantitative real-time PCR over a range of iron concentrations. As expected, the putative biosynthetic genes sidA, sidC and sidD were all strongly up-regulated under iron starvation conditions, although the variable degree of induction indicates complex regulation by a number of transcriptional factors, including the GATA family protein SreA. In contrast, the gene sidE shows no iron-regulation, suggesting that SidE may not be involved in siderophore biosynthesis. The characterisation of the expression patterns of this subset of genes in the iron regulon facilitates further studies into the importance of iron acquisition for pathogenesis of A. fumigatus. [Int Microbiol 2006; 9(4):281-287

Marine Metagenomics: New Tools for the Study and Exploitation of Marine Microbial Metabolism

The marine environment is extremely diverse, with huge variations in pressure and temperature. Nevertheless, life, especially microbial life, thrives throughout the marine biosphere and microbes have adapted to all the divergent environments present. Large scale DNA sequence based approaches have recently been used to investigate the marine environment and these studies have revealed that the oceans harbor unprecedented microbial diversity. Novel gene families with representatives only within such metagenomic datasets represent a large proportion of the ocean metagenome. The presence of so many new gene families from these uncultured and highly diverse microbial populations represents a challenge for the understanding of and exploitation of the biology and biochemistry of the ocean environment. The application of new metagenomic and single cell genomics tools offers new ways to explore the complete metabolic diversity of the marine biome

Epidemiological Interactions between Urogenital and Intestinal Human Schistosomiasis in the Context of Praziquantel Treatment across Three West African Countries

© 2015 Knowles et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. The attached file is the published version of the article

The food superstore revolution: changing times, changing research agendas in the UK

This paper considers the changing scope of research into UK food superstores over a 30-year period. Rather than catalogue changing market shares by format, we seek instead to show how change links to national policy agendas. Academic research has evolved to address the growing complexities of the social, technological, economic and political impacts of the superstore format. We exemplify this by tracing the progression of retail change in Portsmouth, Hampshire, over 30 years. We discover that academic research can conflict with the preconceptions of some public policymakers. The position is exacerbated by a progressive decline in public information – and a commensurate rise in factual data held by commercial data companies – that leaves policymakers with a choice of which data to believe. This casts a shadow over the objectivity of macro-policy as currently formulated. Concerns currently arise because the UK Competition Commission (2008 but ongoing) starts each inquiry afresh with a search for recent data. Furthermore, it has recently called for changes to retail planning – the very arena in which UK superstore research commenced

Genome mining coupled with OSMAC-based cultivation reveal differential production of surugamide A by the marine sponge isolate Streptomyces sp. SM17 when compared to its terrestrial relative S. albidoflavus J1074

Much recent interest has arisen in investigating Streptomyces isolates derived from the marine environment in the search for new bioactive compounds, particularly those found in association with marine invertebrates, such as sponges. Among these new compounds recently identified from marine Streptomyces isolates are the octapeptidic surugamides, which have been shown to possess anticancer and antifungal activities. By employing genome mining followed by an one strain many compounds (OSMAC)-based approach, we have identified the previously unreported capability of a marine sponge-derived isolate, namely Streptomyces sp. SM17, to produce surugamide A. Phylogenomics analyses provided novel insights on the distribution and conservation of the surugamides biosynthetic gene cluster (sur BGC) and suggested a closer relatedness between marine-derived sur BGCs than their terrestrially derived counterparts. Subsequent analysis showed differential production of surugamide A when comparing the closely related marine and terrestrial isolates, namely Streptomyces sp. SM17 and Streptomyces albidoflavus J1074. SM17 produced higher levels of surugamide A than S. albidoflavus J1074 under all conditions tested, and in particular producing >13-fold higher levels when grown in YD and 3-fold higher levels in SYP-NaCl medium. In addition, surugamide A production was repressed in TSB and YD medium, suggesting that carbon catabolite repression (CCR) may influence the production of surugamides in these strains

Smoking Cessation and Cardiovascular Disease Risk Factors: Results from the Third National Health and Nutrition Examination Survey

BACKGROUND: Cigarette smoking is a major risk factor for the development and progression of cardiovascular disease. While smoking is associated with increased levels of inflammatory markers and accelerated atherosclerosis, few studies have examined the impact of smoking cessation on levels of inflammatory markers. The degree and rate at which inflammation subsides after smoking cessation are uncertain. It also remains unclear as to whether traditional risk factors can adequately explain the observed decline in cardiovascular risk following smoking cessation. METHODS AND FINDINGS: Using data from 15,489 individuals who participated in the Third National Health and Nutrition Examination Survey (NHANES III), we analyzed the association between smoking and smoking cessation on levels of inflammatory markers and traditional cardiovascular risk factors. In particular, we examined changes in C-reactive protein, white blood cell count, albumin, and fibrinogen. Inflammatory markers demonstrated a dose-dependent and temporal relationship to smoking and smoking cessation. Both inflammatory and traditional risk factors improved with decreased intensity of smoking. With increased time since smoking cessation, inflammatory markers resolved more slowly than traditional cardiovascular risk factors. CONCLUSION: Inflammatory markers may be more accurate indicators of atherosclerotic disease. Inflammatory markers returned to baseline levels 5 y after smoking cessation, consistent with the time frame associated with cardiovascular risk reduction observed in both the MONICA and Northwick Park Heart studies. Our results suggest that the inflammatory component of cardiovascular disease resulting from smoking is reversible with reduced tobacco exposure and smoking cessation

Integration of robotic surgery into routine practice and impacts on communication, collaboration, and decision making: A realist process evaluation protocol

Background: Robotic surgery offers many potential benefits for patients. While an increasing number of healthcare providers are purchasing surgical robots, there are reports that the technology is failing to be introduced into routine practice. Additionally, in robotic surgery, the surgeon is physically separated from the patient and the rest of the team, with the potential to negatively impact teamwork in the operating theatre. The aim of this study is to ascertain: how and under what circumstances robotic surgery is effectively introduced into routine practice; and how and under what circumstances robotic surgery impacts teamwork, communication and decision making, and subsequent patient outcomes. Methods and design: We will undertake a process evaluation alongside a randomised controlled trial comparing laparoscopic and robotic surgery for the curative treatment of rectal cancer. Realist evaluation provides an overall framework for the study. The study will be in three phases. In Phase I, grey literature will be reviewed to identify stakeholders' theories concerning how robotic surgery becomes embedded into surgical practice and its impacts. These theories will be refined and added to through interviews conducted across English hospitals that are using robotic surgery for rectal cancer resection with staff at different levels of the organisation, along with a review of documentation associated with the introduction of robotic surgery. In Phase II, a multi-site case study will be conducted across four English hospitals to test and refine the candidate theories. Data will be collected using multiple methods: the structured observation tool OTAS (Observational Teamwork Assessment for Surgery); video recordings of operations; ethnographic observation; and interviews. In Phase III, interviews will be conducted at the four case sites with staff representing a range of surgical disciplines, to assess the extent to which the results of Phase II are generalisable and to refine the resulting theories to reflect the experience of a broader range of surgical disciplines. The study will provide (i) guidance to healthcare organisations on factors likely to facilitate successful implementation and integration of robotic surgery, and (ii) guidance on how to ensure effective communication and teamwork when undertaking robotic surgery