Publications by authors named "Maier E"

Hyperthermia and hyperlocomotor activity are commonly reported acute effects of high dose, experimenter-delivered 3,4-methylenedioxymethamphetamine (MDMA). The current investigation was performed to determine short- to long-term physiological and behavioral changes induced by moderate intake MDMA self-administration. In the present study, rats self-administered MDMA (approx.

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New technology enables expansion of newborn screening (NBS) of inborn errors aimed to prevent adverse outcome. In conditions with a large share of asymptomatic phenotypes, the potential harm created by NBS must carefully be weighed against benefit. Policies vary throughout the United States, Australia, and Europe due to limited data on outcome and treatability of candidate screening conditions.

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Uropathogenic Escherichia coli strain 536 possesses two intact copies of the alpha-haemolysin determinant localised on distinct pathogenicity islands. The coding regions of the two hlyCABD operons are conserved; however, upstream sequences are entirely dissimilar. Consequently, expression of the encoded toxin molecules in vitro is highly different.

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Context: Fractures are a major health burden in elderly institutionalized persons. Type 2 diabetes mellitus (DM) has a high prevalence in nursing home patients and has been associated with positive effects on bone mass in younger, community-dwelling elderly.

Objective: The objective of this study was to investigate whether type 2 DM affects bone mass, bone turnover, or prospective fracture rates in frail, elderly women living in nursing homes.

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Aim: Fabry disease is an X-linked lysosomal storage disorder characterized by an accumulation of neutral glycosphingolipids in multiple organ systems caused by alpha-galactosidase A deficiency due to mutations in the GLA gene. The majority of heterozygous females show the characteristic signs and symptoms of the disease, and some of them are severely affected. The current hypothesis for the occurrence of disease manifestations in females is skewed X inactivation favouring the mutant GLA allele.

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Background: Rett syndrome, a common cause of mental retardation in females, is caused by mutations in the MECP2 gene. Most females with MECP2 mutations fulfil the established clinical criteria for Rett syndrome, but single cases of asymptomatic carriers have been described. It is therefore likely that there are individuals falling between these two extreme phenotypes.

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Glutaryl-CoA dehydrogenase (GCDH) deficiency is a rare inborn disorder of L-lysine, L-hydroxylysine, and L-tryptophan metabolism complicated by striatal damage during acute encephalopathic crises. Three decades after its description, the natural history and how to treat this disorder are still incompletely understood. To study which variables influenced the outcome, we conducted an international cross-sectional study in 35 metabolic centers.

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We have investigated outer membrane protein porin from Paracoccus denitrificans for its stability against heat and pH. Pathways of unfolding and refolding have been analyzed. Porin incubated at pH 12.

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The large clostridial cytotoxins toxin A and toxin B from Clostridium difficile are major virulence factors known to cause antibiotic-associated diarrhea and pseudomembranous colitis. Both toxins mono-glucosylate and thereby inactivate small GTPases of the Rho family. Recently, it was reported that toxin B, but not toxin A, induces pore formation in membranes of target cells under acidic conditions.

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Mitochondrial porins are predicted to traverse the outer membrane as a series of beta-strands, but the precise structure of the resulting beta-barrel has remained elusive. Toward determining the positions of the membrane-spanning segments, a series of small deletions was introduced into several of the predicted beta-strands of the Neurospora crassa porin. Overall, three classes of porin variants were identified: i), those producing large, stable pores, indicating deletions likely outside of beta-strands; ii), those with minimal pore-forming ability, indicating disruptions in key beta-strands or beta-turns; and iii), those that formed small unstable pores with a variety of gating and ion-selectivity properties.

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Porins from outer membrane of Gram-negative bacteria have a highly stable structure. Our previous studies on porin from Paracoccus denitrificans showed that the outer membrane protein porin is extremely stable toward heat, pH, and chemical denaturants. The major question we have addressed in this paper is whether the high stability of porin is a consequence of the beta-barrel structure and whether it is required for its function.

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The sequence diversity of human immunodeficiency virus type 1 (HIV-1) represents a major obstacle to the development of an effective vaccine, yet the forces impacting the evolution of this pathogen remain unclear. To address this issue we assessed the relationship between genome-wide viral evolution and adaptive CD8+ T-cell responses in four clade B virus-infected patients studied longitudinally for as long as 5 years after acute infection. Of the 98 amino acid mutations identified in nonenvelope antigens, 53% were associated with detectable CD8+ T-cell responses, indicative of positive selective immune pressures.

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The Bordetella adenylate cyclase toxin-hemolysin (CyaA, ACT, or AC-Hly) forms cation-selective membrane channels and delivers into the cytosol of target cells an adenylate cyclase domain (AC) that catalyzes uncontrolled conversion of cellular ATP to cAMP. Both toxin activities were previously shown to depend on post-translational activation of proCyaA to CyaA by covalent palmitoylation of the internal Lys983 residue (K983). CyaA, however, harbors a second RTX acylation site at residue Lys860 (K860), and the role of K860 acylation in toxin activity is unclear.

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The incidence of severe metabolic crises in medium chain acyl-CoA dehydrogenase deficiency (MCADD) patients homozygous for the common c.985A>G mutation, who had been identified by neonatal screening, was assessed prospectively and compared to retrospective cohort data in unscreened patients with identical genotypes. Logrank test showed a significant reduction of severe metabolic crises in the screened cohort (p<0.

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Medium-chain acyl-CoA dehydrogenase deficiency (MCADD) is the most frequent inherited defect of fatty acid oxidation, with a significant morbidity and mortality in undiagnosed patients. Adverse outcomes can effectively be prevented by avoiding metabolic stress and following simple dietary measures. Therefore, prospective newborn screening (NBS) is being proposed for this condition.

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Noonan syndrome (NS) is an autosomal dominant disorder, characterized by short stature, minor facial anomalies, and congenital heart defects. In approximately 50% of cases the condition is caused by missense mutations in the PTPN11 gene on chromosome 12, resulting in a gain of function of the protein SHP-2. In this study, PTPN11 mutation analysis was performed in 170 NS patients.

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In mammalian intestine, adenosine deaminase (ADA) is expressed at high levels only along the villi of the duodenal epithelium. A duodenum-specific enhancer identified in the second intron of the human ADA gene controls this pattern of expression. This enhancer faithfully recapitulates this expression pattern in transgenic mice, when included in CAT reporter gene constructions.

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This study examined the suitability of the hemolysin secretion system of Escherichia coli for expression and delivery of alpha-hemolysin (HlyA) by the S. typhi Ty21a strain, the only live oral Salmonella vaccine strain licensed for human use, under in vitro and in vivo conditions. For this purpose, two plasmid vectors encoding either the whole alpha-hemolysin of E.

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Detergent extracts of whole cells of the Gram-positive bacterium Tsukamurella inchonensis ATCC 700082, which belongs to the mycolata, were studied for the presence of ion-permeable channels using lipid bilayer experiments. One channel with a conductance of about 4.5 nS in 1 M KCl was identified in the extracts.

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We report a cytochrome c oxidase (COX)-deficient patient, clinically affected with Leigh-like disease, with a homozygous mutation in the COX10 start codon. Two-dimensional gel electrophoresis showed a decrease of fully assembled COX without the accumulation of partially assembled COX subcomplexes. Western blot analysis with antibodies directed to COX subunits I, II, and IV showed a decrease of these subunits in this patient compared with control.

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Detergent extracts of cell envelopes of the gliding bacterium Herpetosiphon aurantiacus formed channels in lipid bilayers. Fast protein liquid chromatography across a HiTrap-Q cation-exchange column demonstrated that a 45-kDa protein forms the channel. The observation of a channel-forming protein suggests that Herpetosiphon aurantiacus Hp a2 has a permeability barrier on its surface.

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Mitochondrial porin facilitates the diffusion of small hydrophilic molecules across the mitochondrial outer membrane. Despite low sequence similarity among porins from different species, a "glycine-leucine-lysine" (GLK) motif is conserved in mitochondrial and Neisseria porins. To investigate the possible roles of these conserved residues, including their hypothesized participation in ATP binding by the protein, we replaced the lysine residue of the GLK motif of Neurospora crassa porin with glutamic acid through site-directed mutagenesis of the corresponding gene.

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Inducible mineralization of TSA (4-toluenesulphonate) by Comamonas testosteroni T-2 is initiated by a secondary transport system, followed by oxygenation and oxidation by TsaMBCD to 4-sulphobenzoate under the regulation of TsaR and TsaQ. Evidence is presented for a novel, presumably two-component transport system (TsaST). It is proposed that TsaT, an outer-membrane porin, formed an anion-selective channel that works in co-operation with the putative secondary transporter, TsaS, located in the inner membrane.

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Background: For a diploid organism such as human, the two alleles of a particular gene can be expressed at different levels due to X chromosome inactivation, gene imprinting, different local promoter activity, or mRNA stability. Recently, imbalanced allelic expression was found to be common in human and can follow Mendelian inheritance. Here we present a method that employs real competitive PCR for allele-specific expression analysis.

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Serratia marcescens outer membrane contains three different general diffusion porins: Omp1, Omp2 and Omp3. Omp1 was cloned and sequenced and it shows a great homology to the family of outer membrane porins that comprises the general porins of enteric bacteria. The gene for Omp1 was transferred into an expression plasmid and was expressed in Escherichia coli UH302 (E.

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