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Background: Diabetes incidence in childhood and youth is increasing worldwide, including autoimmune and non-autoimmune cases. Recent findings suggest that there is a larger than expected proportion of type 2 diabetes in youth, and potential cases of intermediate diabetes phenotypes. Most pediatric diabetes registries focus on type 1 diabetes. Also, there is an absence of reliable data on type 2 diabetes incidence in youth., Aims: The DiMelli study aims to establish a diabetes incidence cohort registry of patients in Germany, diagnosed with diabetes mellitus before age 20 years. It will be used to characterize diabetes phenotypes by immunologic, metabolic, and genetic markers. DiMelli will assess the contribution of obesity and socio-demographic factors to the development of diabetes in childhood and youth., Methods: Recruitment of patients started in 2009, and is expected to continue at a rate of 250 patients per year., Results: 84% of the 216 patients recruited within the first year were positive for multiple islet autoantibodies, 12% for one islet autoantibody, and 4% were islet autoantibody-negative. Patients with multiple islet autoantibodies were younger and had lower fasting C-peptide levels, compared to islet autoantibody-negative patients (median age 10.0 vs. 14.1 years, p < 0.01)., Conclusions: Results from the first year of the study show that DiMelli will help to reveal new knowledge on the etiology of diabetes, and the contribution of genetic predisposition and environmental risk factors to the different types of diabetes.

We determined the complete nucleotide sequence of the New World simian foamy virus (FV) from spider monkey (SFVspm). Starting from a conserved region in the integrase (IN) domain of the pol gene we cloned fragments of the genome up to the 5' end of the long terminal repeat (LTR) into plasmid vectors and elucidated their nucleotide sequence. The 3' end of the genome was determined by direct nucleotide sequencing of PCR products. Each nucleotide of the genome was determined at least two times from both strands. All protein motifs described to be conserved among primate FVs were found in SFVspm. At both the nucleotide and protein levels SFVspm is the most divergent primate FV described to date, reflecting the long-term phylogenetic separation between Old World and New World primate host species (Catarrhini and Platyrrhini, respectively). The molecular probes developed for SFVspm will allow the investigation of trans-species transmissions of this New World foamy virus to humans by serological assays.

G proteins transmit a variety of extracellular signals into intracellular responses. The Galpha and Gbetagamma subunits are both known to regulate effectors. Interestingly, the Galpha subunit also determines subtype specificity of Gbetagamma effector interactions. However, in light of the common paradigm that Galpha and Gbetagamma subunits dissociate during activation, a plausible mechanism of how this subtype specificity is generated was lacking. Using a fluorescence resonance energy transfer (FRET)-based assay developed to directly measure mammalian G protein activation in intact cells, we demonstrate that fluorescent Galpha(i1,2,3), Galpha(z), and Gbeta(1)gamma(2) subunits do not dissociate during activation but rather undergo subunit rearrangement as indicated by an activation-induced increase in FRET. In contrast, fluorescent Galpha(o) subunits exhibited an activation-induced decrease in FRET, reflecting subunit dissociation or, alternatively, a distinct subunit rearrangement. The alpha(B/C)-region within the alpha-helical domain, which is much more conserved within Galpha(i1,2,3) and Galpha(z) as compared with that in Galpha(o), was found to be required for exhibition of an activation-induced increase in FRET between fluorescent Galpha and Gbetagamma subunits. However, the alpha(B/C)-region of Galpha(il) alone was not sufficient to transfer the activation pattern of Galpha(i) to the Galpha(o) subunit. Either residues in the first 91 amino acids or in the C-terminal remainder (amino acids 93-354) of Galpha(il) together with the alpha(B/C)-helical region of Galpha(i1) were needed to transform the Galpha(o)-activation pattern into a Galpha(i1)-type of activation. The discovery of subtype-selective mechanisms of G protein activation illustrates that G protein subfamilies have specific mechanisms of activation that may provide a previously unknown basis for G protein signaling specificity.