Specific excision of the selenocysteine tRNA[Ser]Sec (Trsp) gene in mouse liver demonstrates an essential role of selenoproteins in liver function

Selenium is essential in mammalian embryonic development. However, in adults, selenoprotein levels in several organs including liver can be substantially reduced by selenium deficiency without any apparent change in phenotype. To address the role of selenoproteins in liver function, mice homozygous for a floxed allele encoding the selenocysteine (Sec) tRNA([Ser]Sec) gene were crossed with transgenic mice carrying the Cre recombinase under the control of the albumin promoter that expresses the recombinase specifically in liver. Recombination was nearly complete in mice 3 weeks of age, whereas liver selenoprotein synthesis was virtually absent, which correlated with the loss of Sec tRNA([Ser]Sec) and activities of major selenoproteins. Total liver selenium was dramatically decreased, whereas levels of low molecular weight selenocompounds were little affected. Plasma selenoprotein P levels were reduced by about 75%, suggesting that selenoprotein P is primarily exported from the liver. Glutathione S-transferase levels were elevated in the selenoprotein-deficient liver, suggesting a compensatory activation of this detoxification program. Mice appeared normal until about 24 h before death. Most animals died between 1 and 3 months of age. Death appeared to be due to severe hepatocellular degeneration and necrosis with concomitant necrosis of peritoneal and retroperitoneal fat. These studies revealed an essential role of selenoproteins in liver function.     

Cathodes as electron donors for microbial metabolism: Which extracellular electron transfer mechanisms are involved?

This review illuminates extracellular electron transfer mechanisms that may be involved in microbial bioelectrochemical systems with biocathodes. Microbially-catalyzed cathodes are evolving for new bioprocessing applications for waste(water) treatment, carbon dioxide fixation, chemical product formation, or bioremediation. Extracellular electron transfer processes in biological anodes, were the electrode serves as electron acceptor, have been widely studied. However, for biological cathodes the question remains: what are the biochemical mechanisms for the extracellular electron transfer from a cathode (electron donor) to a microorganism? This question was approached by not only analysing the literature on biocathodes, but also by investigating known extracellular microbial oxidation reactions in environmental processes. Here, it is predicted that in direct electron transfer reactions, c-type cytochromes often together with hydrogenases play a critical role and that, in mediated electron transfer reactions, natural redox mediators, such as PQQ, will be involved in the bioelectrochemical reaction. These mechanisms are very similar to processes at the bioanode, but the components operate at different redox potentials. The biocatalyzed cathode reactions, thereby, are not necessarily energy conserving for the microorganism.     

Complete genome sequence of Thermomonospora curvata type strain (B9)

Thermomonospora curvata Henssen 1957 is the type species of the genus Thermomonospora. This genus is of interest because members of this clade are sources of new antibiotics, enzymes, and products with pharmacological activity. In addition, members of this genus participate in the active degradation of cellulose. This is the first complete genome sequence of a member of the family Thermomonosporaceae. Here we describe the features of this organism, together with the complete genome sequence and annotation. The 5,639,016 bp long genome with its 4,985 protein-coding and 76 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project.     

New Insights to Self‐Aggregation in Ionic Liquid Electrolytes for High‐Energy Electrochemical Devices

Some cations of ionic liquids (ILs) of interest for high‐energy electrochemical storage devices, such as lithium batteries and supercapacitors, have a structure similar to that of surfactants. For such, it is very important to understand if these IL cations tend to aggregate like surfactants since this would affect the ion mobility and thus the ionic conductivity. The aggregation behaviour of ILs consisting of the bis(trifluoromethanesulfonyl)imide anion and different N‐alkyl‐N‐methyl‐pyrrolidinium cations, with the alkyl chain varied from C₃H₇ to C₈H₁₇, was extensively studied with NMR and Raman methods, also in the presence of Li⁺ cations. ²H NMR spin‐lattice and spin‐spin relaxation rates were analyzed by applying the “two step” model of surfactant dynamics. Here we show that, indeed, the cations in these ILs tend to form aggregates surrounded by the anions. The effect is even more pronounced in the presence of dissolved lithium cations.     

Environmental Factors Associated with Disease Progression after the First Demyelinating Event: Results from the Multi-Center SET Study

Objectives

To investigate the associations of environmental MS risk factors with clinical and MRI measures of progression in high-risk clinically isolated syndromes (CIS) after the first demyelinating event.

Methods

We analyzed 211 CIS patients (age: 28.9±7.8 years) enrolled in the SET study, a multi-center study of high-risk CIS patients. Pre-treatment samples were analyzed for IgG antibodies against cytomegalovirus (anti-CMV), Epstein Barr virus (EBV) early nuclear antigen-1 (EBNA-1), viral capsid antigen (VCA), early antigen-diffuse (EA-D), 25 hydroxy-vitamin D3 and cotinine levels and HLA DRB1*1501 status. The inclusion criteria required evaluation within 4 months of the initial demyelinating event, 2 or more brain MRI lesions and the presence of two or more oligoclonal bands in cerebrospinal fluid. All patients were treated with interferon-beta. Clinical and MRI assessments were obtained at baseline, 6, 12, and 24 months.

Results

The time to first relapse decreased and the number of relapses increased with anti-CMV IgG positivity. Smoking was associated with increased number and volume of contrast-enhancing lesions (CEL) during the 2-year period. The cumulative number of CEL and T2 lesions during the 2-year period was greater for individuals in the highest quartile of anti-EBV VCA IgG antibodies. The percent loss of brain volume was increased for those in the highest quartile of with anti-EBV VCA IgG antibodies.

Conclusions

Relapses in CIS patients were associated with CMV positivity whereas anti-EBV VCA positivity was associated with progression on MRI measures, including accumulation of CEL and T2 lesions and development of brain atrophy.     

Complete genome sequence of Coraliomargarita akajimensis type strain (04OKA010-24)

Coraliomargarita akajimensis Yoon et al. 2007 is the type species of the genus Coraliomargarita. C. akajimensis is an obligately aerobic, Gram-negative, non-spore-forming, non-motile, spherical bacterium that was isolated from seawater surrounding the hard coral Galaxea fascicularis. C. akajimensis is of special interest because of its phylogenetic position in a genomically under-studied area of the bacterial diversity. Here we describe the features of this organism, together with the complete genome sequence, and annotation. This is the first complete genome sequence of a member of the family Puniceicoccaceae. The 3,750,771 bp long genome with its 3,137 protein-coding and 55 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project.     

Skin cancer after X-ray treatment for scalp ringworm

Some 2,224 children given X-ray therapy for tinea capitis (ringworm of the scalp) have been followed for up to 50 years to determine cancer incidence, along with a control group of 1,380 tinea capitis patients given only topical medications. The study found a relative risk (RR) of 3.6 (95% confidence interval, 2.3-5.9) for basal cell skin cancer (BCC) of the head and neck among irradiated Caucasians (124 irradiated cases and 21 control cases), in response to a scalp dose of about 4.8 Gy. No melanomas of the head and neck have been seen, and only a few squamous cell carcinomas. About 40% of irradiated cases have had multiple BCCs, for a total of 328 BCCs. Although 25% of both the irradiated and control groups are African-American, only 3 skin cancers have been seen among them, all in the irradiated group, indicating the importance of susceptibility to UV radiation as a cofactor. Light complexion, severe sunburning and North European ancestry were predictive of BCC risk in the irradiated group, but chronic sun exposure was not. Children irradiated at young ages had the highest BCC risk. The RR for BCC risk is approximately constant with time since exposure, suggesting that risk will probably last for a lifetime.     

Pediatric Drug Safety Surveillance in FDA-AERS: A Description of Adverse Events from GRiP Project

Individual case safety reports (ICSRs) are a cornerstone in drug safety surveillance. The knowledge on using these data specifically for children is limited. We studied characteristics of pediatric ICSRs reported to the US Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS). Public available ICSRs reported in children (0–18 years) to FAERS were downloaded from the FDA-website for the period Jan 2004-Dec 2011. Characteristics of these ICSRs, including the reported drugs and events, were described and stratified by age-groups. We included 106,122 pediatric ICSRs (55% boys and 58% from United States) with a median of 1 drug [range 1–3] and 1 event [1–2] per ICSR. Mean age was 9.1 years. 90% was submitted through expedited (15-days) (65%) or periodic reporting (25%) and 10% by non-manufacturers. The proportion and type of pediatric ICSRs reported were relatively stable over time. Most commonly reported drug classes by decreasing frequency were ‘nervous system drugs’ (58%), ‘antineoplastics’ (32%) and ‘anti-infectives’ (25%). Most commonly reported system organ classes were ‘general’ (13%), ‘nervous system’ (12%) and ‘psychiatric’ (11%) disorders. Duration of use could be calculated for 19.7% of the reported drugs, of which 14.5% concerned drugs being used long-term (>6 months). Knowledge on the distribution of the drug classes and events within FAERS is a key first step in developing pediatric specific methods for drug safety surveillance. Because of several differences in terms of drugs and events among age-categories, drug safety signal detection analysis in children needs to be stratified by each age group.     

Inbreeding and incompatibility in Trichogramma nr. brassicae: evidence and implications for quality control

Inbreeding effects and incompatibility relationships were examined in strains of the egg parasitoid Trichogramma nr brassicae (Hymenoptera: Trichogrammatidae) from southeastern Australia. Crosses between strains provided weak evidence of incompatibility in a few cases. However sex ratio in crosses within strains tended to be more female-biased than in crosses between strains. Inbreeding was imposed for four generations (F>0.59) of sib mating. The fitness of inbred strains was compared to that of outbred strains generated by crossing the inbred strains. No effects of inbreeding were found for any of the four female traits examined (fecundity, body length, head width and hind tibia length), indicating that T. nr. brassicae is not subjected to inbreeding depression. Inbreeding effects were also not found for male mating success as expected for the haploid sex. There were differences among strains for all traits apart from fecundity, indicating heritable variation. Strain differences for fitness measures were uncorrelated with wasp size. The potential use of inbreeding in the quality control of Trichogramma for mass-release is discussed. Inbreeding may be a useful tool in minimising the effects of laboratory adaptation, thereby extending the useful life of a strain.