Prevalence gradients of Friedreich's ataxia and R1b haplotype in Europe co-localize, suggesting a common Palaeolithic origin in the Franco-Cantabrian ice age refuge.

Combining data from epidemiological studies in Friedreich's Ataxia (FRDA) and patient organization membership lists, shows that FRDA prevalence exhibits large regional differences in Europe with a prevalence gradient from west to east. Highest levels are observed in northern Spain, south of France and Ireland, lowest levels in Scandinavia and Russia. The observed distribution of FRDA in Europe co-localizes with the gradient of the chromosomal R1b marker as detected within west Europe.

Pharmacokinetic properties and metabolism of idebenone.

Four phase 1 studies were conducted to assess the pharmacokinetics and metabolism of idebenone (including parent drug and inactive metabolites QS10, QS6, and QS4) and to evaluate the safety of a wide range of idebenone doses and regimens in healthy adult men. After a single oral dose of idebenone 150 mg, 750 mg, or 1050 mg in fasted or fed subjects, blood samples were taken for up to 72 hours. In one study, after a single oral dose and a 7-day washout period, subjects received repeated doses of idebenone 150 mg or 750 mg every 8 hours for 14 days.

Diagnosis and treatment of Friedreich ataxia: a European perspective.

Friedreich ataxia is the most frequent hereditary ataxia, with an estimated prevalence of 3-4 cases per 100,000 individuals. This autosomal-recessive neurodegenerative disease is characterized by progressive gait and limb ataxia, dysarthria, lower-limb areflexia, decreased vibration sense, muscular weakness in the legs, and a positive extensor plantar response. Non-neurological signs include hypertrophic cardiomyopathy and diabetes mellitus.

Pharmacokinetics and metabolism of idebenone in healthy male subjects.

Purpose: Idebenone is a synthetic analogue of ubiquinone that may be beneficial in the treatment of Friedreich's ataxia. Since in previous pharmacokinetic trials only lower doses were studied, it was the aim of this study to evaluate the pharmacokinetics of idebenone in higher doses of up to 2,250 mg/day.

Methods: In this open, randomized trial, 25 healthy male subjects received first either a single oral dose of 150 mg or 750 mg of idebenone, then the same dose given at 8-h intervals for 14 days.

Relaxation behavior of rovibrationally excited H2 in a rarefied expansion.

The evolution of the rotational and vibrational distributions of molecular hydrogen in a hydrogen plasma expansion is measured using laser induced fluorescence in the vacuum-UV range. The evolution of the distributions along the expansion axis shows the relaxation of the molecular hydrogen from the high temperature in the upstream region to the low ambient temperature in the downstream region. During the relaxation, the vibrational distribution, which has been recorded up to v = 6, is almost frozen in the expansion and resembles a Boltzmann distribution at T approximately 2200 K.

Behavior of the H atom velocity distribution function within the shock wave of a hydrogen plasma jet.

The evolution of the ground-state hydrogen atom velocity distribution function throughout the stationary shock wave of a supersonic hydrogen plasma jet (3 View Article and Find Full Text PDF

Transport of ground-state hydrogen atoms in a plasma expansion.

The transport of ground-state atomic hydrogen in the expansion of a thermal plasma generated from an Ar-H2 mixture is studied by means of laser-based diagnostic techniques. The flow of hydrogen atoms is investigated by two-photon excitation laser-induced fluorescence (LIF), whereas Ar atoms are probed by LIF as well as by UV Rayleigh scattering. The transport of Ar atoms can be fully understood in terms of a free jet flow; H atoms on the contrary exhibit an anomalous behavior.

The trp RNA-binding attenuation protein (TRAP) regulates the steady-state levels of transcripts of the Bacillus subtilis folate operon.

The Bacillus subtilis folate operon contains nine genes. The first six genes are involved in the biosynthesis of folic acid and tryptophan and have been characterized previously. The 3'-region of the folate operon contains three additional ORFs: orf3, potentially encoding a DNA-binding protein of 68 amino acids, orf4, encoding a protein of 338 amino acids with homology to the Orf1 of the E.

Enzymic characterization of Bacillus subtilis GTP cyclohydrolase I. Evidence for a chemical dephosphorylation of dihydroneopterin triphosphate.

GTP cyclohydrolase I catalyses the first committing step in the biosynthesis of the pterin moiety of folic acid: conversion of GTP to dihydroneopterin triphosphate. GTP cyclohydrolase I of Bacillus subtilis was purified to homogeneity and shown to have a homo-octameric structure. The enzyme had an apparent Km for GTP of 4 microM and, in the absence of cations, a Vmax.

Roles of U4 and U6 snRNAs in the assembly of splicing complexes.

A series of U4 and U6 snRNA mutants was analysed in Xenopus oocytes to determine whether they block splicing complex assembly or splicing itself. All the U4 and U6 mutants found to be inactive in splicing complementation resulted in defects in assembly of either U4/U6 snRNP or of splicing complexes. No mutants were found to separate the entry of U5 and U6 snRNAs into splicing complexes and neither of these RNAs was able to associate with the pre-mRNA in the absence of U4.

Domains of U4 and U6 snRNAs required for snRNP assembly and splicing complementation in Xenopus oocytes.

Structure-function relationships in the vertebrate U4-U6 snRNP have been analysed by assaying the ability of mutant RNAs to form U4-U6 snRNPs and to function in splicing complementation in Xenopus oocytes. The mutants define three categories of domain within the RNAs. First, domains which are not essential for splicing.

A U-snRNA gene-specific upstream element and a -30 'TATA box' are required for transcription of the U2 snRNA gene of Arabidopsis thaliana.

The U2 and U5 snRNA genes of Arabidopsis thaliana contain in their promoter regions two elements with conserved sequence and position. To test the significance of this conservation we have made a construction in which the promoter of the U2 RNA gene is replaced by the synthetic 98 bp long sequence containing the two conserved elements: an upstream sequence element, GTCCCACATCG (USE, pos. -78 to -68), and a TATA-like sequence TATAAATA (-33 to -26), positioned approximately three helical turns apart, as in the wild-type promoter.

Structure and expression of the U5 snRNA gene of Arabidopsis thaliana. Conserved upstream sequence elements in plant U-RNA genes.

We have previously characterized the U2 small nuclear (sn) RNA gene family of Arabidopsis thaliana. To find out the structural features of upstream and downstream non-coding regions that are shared by different U-RNA genes in higher plants we have isolated the gene encoding a 125 nt-long U5 snRNA of Arabidopsis. Activity of the cloned gene was demonstrated in stably transformed tobacco calli and by transient expression in transfected protoplasts of Nicotiana plumbaginifolia.

Plastocyanin of Arabidopsis thaliana; isolation and characterization of the gene and chloroplast import of the precursor protein.

A genomic clone encoding the plastocyanin precursor was isolated from an Arabidopsis thaliana lambda EMBL3 library, with the help of a heterologous hybridization probe. The nucleotide (nt) sequence encoding the 171-amino acid precursor protein and 650 bp of the 5'-flanking region were determined. S1 nuclease mapping showed the Arabidopsis coding region to be uninterrupted and the transcript to possess an untranslated leader of approx.

Structure of U2 snRNA genes of Arabidopsis thaliana and their expression in electroporated plant protoplasts.

We have characterized the U2 snRNA gene family in the higher plant Arabidopsis thaliana. It consists of 10-15 genes which do not appear to be closely clustered. Six of the U2 genes were sequenced and the structure of the Arabidopsis U2 RNA termini was determined in order to define the coding regions.

Effect of 1,8-dihydroxy-9-anthrone (anthralin) on rat hepatic ornithine decarboxylase activity in vivo.

Intraperitoneal injection of the non-phorbol tumor promoter anthralin (1,8-dihydroxy-9-anthrone) in male rats resulted in an increase of hepatic ornithine decarboxylase (ODC) activity. Maximal activity was observed 8 h after promoter administration reaching levels about 30 times over control. The kinetics of anthralin dependent ODC induction differed markedly from that by either 12-O-tetradecanoylphorbol-13-acetate (TPA) or phenobarbital (PB) (Bisschop et al.