MACS J0553.4-3342: a young merging galaxy cluster caught through the eyes of Chandra and HST

FWN – Publicaties zonder aanstelling Universiteit Leide

Meta-analysis of type 2 Diabetes in African Americans Consortium

Type 2 diabetes (T2D) is more prevalent in African Americans than in Europeans. However, little is known about the genetic risk in African Americans despite the recent identification of more than 70 T2D loci primarily by genome-wide association studies (GWAS) in individuals of European ancestry. In order to investigate the genetic architecture of T2D in African Americans, the MEta-analysis of type 2 DIabetes in African Americans (MEDIA) Consortium examined 17 GWAS on T2D comprising 8,284 cases and 15,543 controls in African Americans in stage 1 analysis. Single nucleotide polymorphisms (SNPs) association analysis was conducted in each study under the additive model after adjustment for age, sex, study site, and principal components. Meta-analysis of approximately 2.6 million genotyped and imputed SNPs in all studies was conducted using an inverse variance-weighted fixed effect model. Replications were performed to follow up 21 loci in up to 6,061 cases and 5,483 controls in African Americans, and 8,130 cases and 38,987 controls of European ancestry. We identified three known loci (TCF7L2, HMGA2 and KCNQ1) and two novel loci (HLA-B and INS-IGF2) at genome-wide significance (4.15 × 10(-94)<P<5 × 10(-8), odds ratio (OR)  = 1.09 to 1.36). Fine-mapping revealed that 88 of 158 previously identified T2D or glucose homeostasis loci demonstrated nominal to highly significant association (2.2 × 10(-23) < locus-wide P<0.05). These novel and previously identified loci yielded a sibling relative risk of 1.19, explaining 17.5% of the phenotypic variance of T2D on the liability scale in African Americans. Overall, this study identified two novel susceptibility loci for T2D in African Americans. A substantial number of previously reported loci are transferable to African Americans after accounting for linkage disequilibrium, enabling fine mapping of causal variants in trans-ethnic meta-analysis studies.Peer reviewe

Main microbial mechanisms of pesticide degradation in soils

183 ref. chap. 4International audienc

PCR detection of the MCD gene and evidence of sequence homology between the degradative genes and plasmids from diverse carbofuran-degrading bacteria

International audienc

Effects of acute gamma irradiation on chemical, physical and biological properties of soils

The use of gamma (-) irradiation as a method for soil sterilisation for laboratory experiments has been recommended over other sterilisation techniques.We reviewed literature dating back over 50 years to investigate the chemical and biological effects on -irradiated soils and to determine its practicality for sterilising soils which will subsequently be used for experimental purposes. Typically, -irradiation at 10 kGy will eliminate actinomycetes, fungi and invertebrates in most soils. The majority of soil bacteria are eliminated by 20 kGy, however, a dose higher than 70 kGy may be required to kill certain radio-resistant bacteria. We recommend prior to experimentation that the radiosensitivity of soils are determined so as to ensure the desired chemical and biological effects are achieved. -Irradiation may not be an appropriate method for all experiments as it can influence soil chemical properties, in particular soil nitrate and ammonium levels. Where chemical stability is required we recommend sterilising soils air-dry rather than moist

Diversity of carbofuran-degrading soil bacteria and detection of plasmid-encoded sequences homologous to the MED gene

46 ref.International audienc

Genetic diversity of carbofuran-degrading soil bacteria

International audienc

Microbial component of radiocaesium retention in highly organic soils.

The mobility of radiocaesium in the environment and its availability for plant uptake are strongly dependent on the processes controlling its retention in soils. The role of the soil microbial biomass in radiocaesium retention may be important in highly organic soils, yet this role has received little attention. Currently, the techniques used to assess radiocaesium retention tend to ignore the microbial component and, as a result, may compromise assessment of retention. We present here evidence that the microbial component cannot be ignored in such assays and propose changes that recognise the importance of maintaining biological activity in samples of organic soils