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Background The interaction between genetic, epigenetic and environmental factors plays an important role in the aetiology of hypertension. GWAS and observational studies link the C677T polymorphism in methylenetetrahydrofolate reductase (MTHFR) with hypertension, while riboflavin, the MTHFR cofactor, has been shown to reduce blood pressure and global DNA methylation in homozygous (TT genotype) individuals. It is currently unclear whether riboflavin modulates DNA methylation of other hypertension-related genes. Objectives To compare DNA methylation of hypertension-related genes in adults stratified by MTHFR genotype and effect of riboflavin intervention in adults with the variant MTHFR 677TT genotype. Method Pyrosequencing was carried out for hypertension-related genes (ACE, AGTR1, GCK, GNA12, IGF2, MMP9 and NOS3) in blood samples from participants in previous trials (CC, n = 40; TT, n = 40). The effect of intervention with riboflavin (1.6 mg/d for16 weeks) or placebo on DNA methylation was investigated in adults with the variant MTHFR 677TT genotype (n = 80). Results Individuals with the MTHFR 677TT v CC genotype had significantly higher average DNA methylation at NOS3 (+1.66%, P = 0.044). In response to riboflavin supplementation in TT individuals, there was an increase in average DNA methylation at IGF2 (+1.09%, P = 0.019) and a decrease at ACE (−0.44%, P = 0.021) in females only. Specific CpG sites were hypomethylated in GNA12 and hypermethylated in AGTR1. Conclusion This study provides the first RCT evidence that riboflavin alters DNA methylation of hypertension-related genes in adults with the MTHFR 677TT genotype, providing some insight into mechanisms linking hypertension with the genotype-specific response of BP to riboflavin.

DNA methylation is important in regulating gene expression and genomic stability while aberrant DNA methylation is associated with disease. Riboflavin (FAD) is a cofactor for methylenetetrahydrofolate reductase (MTHFR), a critical enzyme in folate recycling, which generates methyl groups for homocysteine remethylation to methionine, the pre-cursor to the universal methyl donor S-adenosylmethionine (SAM). A polymorphism (C677T) in MTHFR results in decreased MTHFR activity and increased homocysteine concentration. Previous studies demonstrated that riboflavin modulates this phenotype in homozygous adults (MTHFR 677 TT genotype), however, DNA methylation was not considered. This study examined DNA methylation, globally and at key MTHFR regulatory sites, in adults stratified by MTHFR genotype and the effect of riboflavin supplementation on DNA methylation in individuals with the 677 TT genotype. Samples were accessed from participants, screened for the MTHFR C677T polymorphism, who participated in observational (n = 80) and targeted riboflavin (1.6 mg/day) RCTs (n = 80). DNA methylation at LINE-1 and key regulatory regions of the MTHFR locus were analysed by pyrosequencing in peripheral blood leukocytes. LINE-1 (+1.6%; p = 0.011) and MTHFR south shelf (+4.7%, p 0.001) were significantly hypermethylated in individuals with the MTHFR 677 TT compared to CC genotype. Riboflavin supplementation resulted in decreased global methylation, albeit only significant at one CpG. A significant reduction in DNA methylation at the MTHFR north shore (-1.2%, p 0.001) was also observed in TT adults following intervention with riboflavin. This provides the first RCT evidence that DNA methylation may be modulated by riboflavin in adults with the MTHFR 677 TT genotype.

The in vitro activity and spectrum of tedizolid and comparators were analyzed against 6884 Gram-positive clinical isolates collected from multiple US and European sites as part of the Surveillance of Tedizolid Activity and Resistance Program in 2011 and 2012. Organisms included 4499 Staphylococcus aureus, 537 coagulase-negative staphylococci (CoNS), 873 enterococci, and 975 β-hemolytic streptococci. The MIC values that inhibited 90% of the isolates within each group (MIC90) were 0.25 μg/mL for Staphylococcus epidermidis and β-hemolytic streptococci and 0.5 μg/mL for S. aureus, other CoNS, and enterococci. Of 16 isolates with elevated tedizolid or linezolid MIC values (intermediate or resistant isolates), 10 had mutations in the genes encoding 23S rRNA (primarily G2576T), 5 had mutations in the genes encoding ribosomal proteins L3 or L4, and 5 carried the cfr multidrug resistance gene. Overall, tedizolid showed excellent activity against Gram-positive bacteria and was at least 4-fold more potent than linezolid against wild-type and linezolid-resistant isolates. Given the low overall frequency of isolates that would be resistant to tedizolid at the proposed break point of 0.5 μg/mL (0.19%) and potent activity against contemporary US and European isolates, tedizolid has the potential to serve as a valuable therapeutic option in the treatment of infections caused by Gram-positive pathogens.

Antimicrobial susceptibilities of contemporary Pseudomonas aeruginosa clinical isolates were determined from the CAPITAL 2010 surveillance program. Isolates were collected from 100 sites throughout the USA and Puerto Rico, and included isolates representing a range of patient demographics and infection types. A total of 2722 isolates were tested for susceptibility to a broad spectrum of agents, with susceptibilities ranging from 98.8% for colistin to 74% for levofloxacin. Doripenem was the most active carbapenem agent, with 88.6% of isolates susceptible, in comparison with 78.1% and 84.6% for imipenem and meropenem, respectively. Lower respiratory tract isolates and isolates from the intensive care unit setting were the least susceptible overall. Resistance rates were typically highest in lower respiratory tract isolates, with the exception of urinary tract isolates, which displayed the highest resistance for levofloxacin. Overall, multidrug-resistant isolates comprised 14.8% of the total sample population.

Private sector involvement in desalination projects in the Mediterranean Middle East (Algeria, Egypt, Israel, Jordan, Lebanon, Libya, Morocco, Syria and Tunisia) has in the main been limited to the provision of facilities under turnkey type contracts — with the exception of Israel which has recently embarked on a series of BOO/BOT type projects. The first part of this paper outlines the principal types of private sector involvement employed on infrastructure projects globally today — from management contracts to concessions to full-scale privatisations. Each of the MME countries is then reviewed in turn to identify the forms of private sector involvement experienced to date on infrastructure projects, with particular emphasis on desalination projects. The second part of the paper sets out the general drivers and constraints behind private sector involvement on desalination projects from both public and private sector perspectives. Drivers include: need (either to replace or supplement existing supplies); lack of alternative supplies; desire for private sector expertise, lack of public sector funding; and availability of IPP's. Constraints include: political opposition; lack of appropriate regulatory/legal frameworks; inability to pay for services; high country risk; and lack of track record of completed PSP projects. The application of these drivers and constraints to each country in the MME is then undertaken, and the results help inform the likely future prospects for private sector involvement on desalination projects in the foreseeable future.

Over the past decade, excessive sleepiness among children and adolescents has been identified as a major societal concern. Professionals working with pediatric groups must increasingly factor sleepiness into assessments of waking function. We define and discuss excessive sleepiness in children and adolescents and review available evidence regarding effects on behavior, mood, and performance. Findings for daytime sleepiness and subsequent impairment in these domains are classified as robust to unknown. Empirical evidence clearly indicates that children and adolescents experience significant daytime sleepiness as a result of inadequate or disturbed sleep. The specific effect of sleepiness on functional domains in pediatric groups are less well-studied, but existing data suggests that children are likely to experience impairment in behavioral, mood, and performance domains. However, such variables as developmental differences in the type and degree of impairment, the degree of sleep disturbance required to produce impairments, and potential risk and protective factors for the effects of sleepiness in children have yet to be described. Further research is clearly warranted, and we discuss important questions and methodological concerns to encourage inquiry in both clinical and experimental settings. Advice is offered with regard to screening for sleep problems and associated sleepiness with children and adolescents.

Objectives Ivacaftor is effective in the treatment of patients with CF and the G551D gating mutation. We present faecal analysis results of the CORK cohort, a single-centre, adult (n = 20), prospective, longitudinal study of G551D clinical responders (median follow-up 12 months), examining the gut microbiota, exocrine pancreatic function and intestinal inflammation on a 3 monthly basis after commencing treatment. Methods Stool samples pre- and 3 monthly post commencement of ivacaftor in 20 adult patients underwent metagenomic profiling of faecal microbiota. Faecal elastase-1 (FE-1), faecal calprotectin (FC) and faecal lactoferrin (FL) were measured using commercially available ELISA kits. Results Ivacaftor did not significantly alter gut microbial diversity, as measured by chao1 (p = 0.886). At phylum, family and genus levels significant increases were observed in Bacteroidetes (p = 0.044), Bacteroidaceae (p = 0.021) and Bacteroides (p = 0.021). Significant decreases were observed in Microbacteriaceae (p = 0.003) and Eubacteriaceae (p = 0.014). A significant positive correlation was seen between FEV1 and gut microbiota diversity following treatment (r = 0.4, p=0.002). No significant difference was measured in levels of FE-1 (p = 0.267), FC (p = 0.406) or FL (p = 0.779). Conclusion Ivacaftor therapy has a normalisation effect on the gut microbiota, directing the microbiota towards a non-CF profile. Despite this elevated intestinal inflammation was sustained. Lack of exocrine pancreatic recovery may reflect established exocrine pancreatic dysfunction in an adult cohort. On-going longitudinal prospective data may demonstrate further improvements in the gut health of this cohort.