Malodorous volatile organic sulfur compounds: Sources,sinks and significance in inland waters

Volatile Organic Sulfur Compounds (VOSCs) are instrumental in global S-cycling and greenhouse gas production. VOSCs occur across a diversity of inland waters, and with widespread eutrophication and climate change, are increasingly linked with malodours in organic-rich waterbodies and drinking-water supplies. Compared with marine systems, the role of VOSCs in biogeochemical processes is far less well characterized for inland waters, and often involves different physicochemical and biological processes. This review provides an updated synthesis of VOSCs in inland waters, focusing on compounds known to cause malodours. We examine the major limnological and biochemical processes involved in the formation and degradation of alkylthiols, dialkylsulfides, dialkylpolysulfides, and other organosulfur compounds under different oxygen, salinity and mixing regimes, and key phototropic and heterotrophic microbial producers and degraders (bacteria, cyanobacteria, and algae) in these environs. The data show VOSC levels which vary significantly, sometimes far exceeding human odor thresholds, generated by a diversity of biota, biochemical pathways, enzymes and precursors. We also draw attention to major issues in sampling and analytical artifacts which bias and preclude comparisons among studies, and highlight significant knowledge gaps that need addressing with careful, appropriate methods to provide a more robust understanding of the potential effects of continued global development.     

Changes in the levels of indoleamine phytochemicals during véraison and ripening of wine grapes

Abstract: Melatonin and serotonin have previously been described in mature wine grapes and finished wines, but the metabolism of these signalling molecules in the development of wine grapes has not previously been investigated. We harvested wine grapes at different stages of development from lag phase through véraison from eight different commercial vineyards representing a diversity of growing conditions, management practices, merlot varietals and localized ecosystems to determine whether different patterns in melatonin and serotonin can be found in wine grapes during seed development and berry maturation. Melatonin was detected in 45% of the fully developed purple, postvéraison grapes but only found in 23% of prelag phase samples. However, the actual concentration of melatonin was highest in wine grapes harvested at the early stage of véraison when the seed is developing. Serotonin was not detected in any of the prelag phase grapes but was consistently detected in 30–35% of grapes harvested during the véraison transition at consistent levels of about 8–10 μg/g. Interestingly, the nitrogen storage compound γ‐aminobutyric acid was also found at about 115 μg/g in 77% of early stage green grapes and declined in both prevalence and concentration with ripening. Together, these data are indicative of a potential role for these molecules in the development and maturation of wine grapes.     

Guide to designing, conducting, publishing and communicating results of clinical studies involving probiotic applications in human participants

The heterogeneity of human clinical trials to assess the effectiveness of probiotics presents challenges regarding interpretation and comparison. Evidence obtained from clinical trials among a population with a disease or specific risk factors may not be generalizable to healthy individuals. The evaluation of interventions in healthy persons requires careful selection of outcomes due to the absence of health indicators and the low incidence of preventable conditions. Given the tremendous resources invested in such trials, development of consistent approaches to assessing the effectiveness of probiotics would be beneficial. Furthermore, the reporting, presentation and communication of results may also affect the validity of the scientific evidence obtained from a trial. This review outlines the challenges associated with the design, implementation, data analysis and interpretation of clinical trials in humans involving probiotics. Best practices related to their design are offered along with recommendations for enhanced collaboration to advance research in this emerging field.     

A survey of tobacco dependence treatment guidelines in 31 countries

Aims The Framework Convention on Tobacco Control (FCTC) asks countries to develop and disseminate comprehensive evidence‐based guidelines and promote adequate treatment for tobacco dependence, yet to date no summary of the content of existing guidelines exists. This paper describes the national tobacco dependence treatment guidelines of 31 countries. Design, setting, participants A questionnaire on tobacco dependence treatment guidelines was sent by e‐mail to a convenience sample of contacts working in tobacco control in 31 countries in 2007. Completed questionnaires were received from respondents in all 31 countries. During the course of these enquiries we also made contact with people in 14 countries that did not have treatment guidelines and sent them a short questionnaire asking about their plans to produce guidelines. Measurements The survey instrument was a 17‐item questionnaire asking the following key questions: do the guidelines recommend brief interventions, intensive behavioural support, medications; which medications; do the guidelines apply to the whole health‐care system and all professionals; do they refer explicitly to the Cochrane database; are they based on another country's guidelines; are they national or more local; are they endorsed formally by government; did they undergo peer review; who funded them; where were they published; do they include evidence on cost effectiveness of treatment? Findings According to respondents, all their countries' guidelines recommended brief advice, intensive behavioural support and nicotine replacement therapy (NRT); 84% recommended bupropion; 19% recommended varenicline; and 35% recommended telephone quitlines. Nearly half (48%) included cost‐effectiveness evidence. Seventy‐one per cent were supported formally by their government and 65% were supported financially by the government. Most (84%) used the Cochrane reviews as a source of evidence, 84% underwent a peer review process and 55% were based on the guidelines of other countries, most often the United States and England. Conclusion Overall, the guidelines reviewed followed the evidence base closely, recommending brief interventions, intensive behavioural support and NRT, and most recommended bupropion. Varenicline was not on the market in most of the countries in this survey when their guidelines were written, illustrating the need for guidelines to be updated periodically. None recommended interventions not proven to be effective, and some recommended explicitly against specific interventions (for lack of evidence). Most were peer‐reviewed, many through lengthy and rigorous procedures, and most were endorsed or supported formally by their governments. Some countries that did not have guidelines expressed a need for technical support, emphasizing the need for countries to share experience, something the FCTC process is well placed to support.