167 research outputs found

    The impact of measures to reduce ambient air PM10 concentrations originating from road dust, evaluated for a street canyon in Helsinki

    Get PDF
    We have numerically evaluated how effective selected potential measures would be for reducing the impact of road dust on ambient air particulate matter (PM10). The selected measures included a reduction of the use of studded tyres on light-duty vehicles and a reduction of the use of salt or sand for traction control. We have evaluated these measures for a street canyon located in central Helsinki for four years (2007–2009 and 2014). Air quality measurements were conducted in the street canyon for two years, 2009 and 2014. Two road dust emission models, NORTRIP (NOn-exhaust Road TRaffic Induced Particle emissions) and FORE (Forecasting Of Road dust Emissions), were applied in combination with the Operational Street Pollution Model (OSPM), a street canyon dispersion model, to compute the street increments of PM10 (i.e. the fraction of PM10 concentration originating from traffic emissions at the street level) within the street canyon. The predicted concentrations were compared with the air quality measurements. Both road dust emission models reproduced the seasonal variability of the PM10 concentrations fairly well but under-predicted the annual mean values. It was found that the largest reductions of concentrations could potentially be achieved by reducing the fraction of vehicles that use studded tyres. For instance, a 30 % decrease in the number of vehicles using studded tyres would result in an average decrease in the non-exhaust street increment of PM10 from 10 % to 22 %, depending on the model used and the year considered. Modelled contributions of traction sand and salt to the annual mean non-exhaust street increment of PM10 ranged from 4 % to 20 % for the traction sand and from 0.1 % to 4 % for the traction salt. The results presented here can be used to support the development of optimal strategies for reducing high springtime particulate matter concentrations originating from road dust. Short summary Nordic countries experience the deterioration of air quality in springtime due to high PM10 concentrations. Non-exhaust emissions from vehicular traffic are regarded as the most significant source of particulate air pollution during this time of year. The results from this study demonstrate the fact that changes in winter tyre types and adjustments to road maintenance could substantially reduce non-exhaust emissions

    Untreated PKU patients without intellectual disability: What do they teach us?

    Get PDF
    Phenylketonuria (PKU) management is aimed at preventing neurocognitive and psychosocial dysfunction by keeping plasma phenylalanine concentrations within the recommended target range. It can be questioned, however, whether universal plasma phenylalanine target levels would result in optimal neurocognitive outcomes for all patients, as similar plasma phenylalanine concentrations do not seem to have the same consequences to the brain for each PKU individual. To better understand the inter-individual differences in brain vulnerability to high plasma phenylalanine concentrations, we aimed to identify untreated and/or late-diagnosed PKU patients with near-normal outcome, despite high plasma phenylalanine concentrations, who are still alive. In total, we identified 16 such cases. While intellectual functioning in these patients was relatively unaffected, they often did present other neurological, psychological, and behavioral problems. Thereby, these β€œunusual” PKU patients show that the classical symptomatology of untreated or late-treated PKU may have to be rewritten. Moreover, these cases show that a lack of intellectual dysfunction despite high plasma phenylalanine concentrations does not necessarily imply that these high phenylalanine concentrations have not been toxic to the brain. Also, these cases may suggest that different mechanisms are involved in PKU pathophysiology, of which the relative importance seems to differ between patients and possibly also with increasing age. Further research should aim to better distinguish PKU patients with respect to their cerebral effects to high plasma phenylalanine concentrations

    Structural analysis of haemoglobin binding by HpuA from the Neisseriaceae family

    Get PDF
    The Neisseriaceae family of bacteria causes a range of diseases including meningitis, septicaemia, gonorrhoea and endocarditis, and extracts haem from haemoglobin as an important iron source within the iron-limited environment of its human host. Herein we report crystal structures of apo- and haemoglobin-bound HpuA, an essential component of this haem import system. The interface involves long loops on the bacterial receptor that present hydrophobic side chains for packing against the surface of haemoglobin. Interestingly, our structural and biochemical analyses of Kingella denitrificans and Neisseria gonorrhoeae HpuA mutants, although validating the interactions observed in the crystal structure, show how Neisseriaceae have the fascinating ability to diversify functional sequences and yet retain the haemoglobin binding function. Our results present the first description of HpuA’s role in direct binding of haemoglobin

    A European spectrum of pharmacogenomic biomarkers: Implications for clinical pharmacogenomics

    Get PDF
    Pharmacogenomics aims to correlate inter-individual differences of drug efficacy and/or toxicity with the underlying genetic composition, particularly in genes encoding for protein factors and enzymes involved in drug metabolism and transport. In several European populations, particularly in countries with lower income, information related to the prevalence of pharmacogenomic biomarkers is incomplete or lacking. Here, we have implemented the microattribution approach to assess the pharmacogenomic biomarkers allelic spectrum in 18 European populations, mostly from developing European countries, by analyzing 1,931 pharmacogenomics biomarkers in 231 genes. Our data show significant interpopulation pharmacogenomic biomarker allele frequency differences, particularly in 7 clinically actionable pharmacogenomic biomarkers in 7 European populations, affecting drug efficacy and/or toxicity of 51 medication treatment modalities. These data also reflect on the differences observed in the prevalence of high-risk genotypes in these populations, as far as common markers in the CYP2C9, CYP2C19, CYP3A5, VKORC1, SLCO1B1 and TPMT pharmacogenes are concerned. Also, our data demonstrate notable differences in predicted genotype-based warfarin dosing among these populations. Our findings can be exploited not only to develop guidelines for medical prioritization, but most importantly to facilitate integration of pharmacogenomics and to support pre-emptive pharmacogenomic testing. This may subsequently contribute towards significant cost-savings in the overall healthcare expenditure in the participating countries, where pharmacogenomics implementation proves to be cost-effective

    An Outer Membrane Receptor of Neisseria meningitidis Involved in Zinc Acquisition with Vaccine Potential

    Get PDF
    Since the concentration of free iron in the human host is low, efficient iron-acquisition mechanisms constitute important virulence factors for pathogenic bacteria. In Gram-negative bacteria, TonB-dependent outer membrane receptors are implicated in iron acquisition. It is far less clear how other metals that are also scarce in the human host are transported across the bacterial outer membrane. With the aim of identifying novel vaccine candidates, we characterized in this study a hitherto unknown receptor in Neisseria meningitidis. We demonstrate that this receptor, designated ZnuD, is produced under zinc limitation and that it is involved in the uptake of zinc. Upon immunization of mice, it was capable of inducing bactericidal antibodies and we could detect ZnuD-specific antibodies in human convalescent patient sera. ZnuD is highly conserved among N. meningitidis isolates and homologues of the protein are found in many other Gram-negative pathogens, particularly in those residing in the respiratory tract. We conclude that ZnuD constitutes a promising candidate for the development of a vaccine against meningococcal disease for which no effective universal vaccine is available. Furthermore, the results suggest that receptor-mediated zinc uptake represents a novel virulence mechanism that is particularly important for bacterial survival in the respiratory tract

    The Genetic Landscape and Epidemiology of Phenylketonuria

    Get PDF
    Phenylketonuria (PKU), caused by variants in the phenylalanine hydroxylase (PAH) gene, is the most common autosomal-recessive Mendelian phenotype of amino acid metabolism. We estimated that globally 0.45 million individuals have PKU, with global prevalence 1:23,930 live births (range 1:4,500 [Italy]–1:125,000 [Japan]). Comparing genotypes and metabolic phenotypes from 16,092 affected subjects revealed differences in disease severity in 51 countries from 17 world regions, with the global phenotype distribution of 62% classic PKU, 22% mild PKU, and 16% mild hyperphenylalaninemia. A gradient in genotype and phenotype distribution exists across Europe, from classic PKU in the east to mild PKU in the southwest and mild hyperphenylalaninemia in the south. The c.1241A>G (p.Tyr414Cys)-associated genotype can be traced from Northern to Western Europe, from Sweden via Norway, to Denmark, to the Netherlands. The frequency of classic PKU increases from Europe (56%) via Middle East (71%) to Australia (80%). Of 758 PAH variants, c.1222C>T (p.Arg408Trp) (22.2%), c.1066βˆ’11G>A (IVS10βˆ’11G>A) (6.4%), and c.782G>A (p.Arg261Gln) (5.5%) were most common and responsible for two prevalent genotypes: p.[Arg408Trp];[Arg408Trp] (11.4%) and c.[1066βˆ’11G>A];[1066βˆ’11G>A] (2.6%). Most genotypes (73%) were compound heterozygous, 27% were homozygous, and 55% of 3,659 different genotypes occurred in only a single individual. PAH variants were scored using an allelic phenotype value and correlated with pre-treatment blood phenylalanine concentrations (n = 6,115) and tetrahydrobiopterin loading test results (n = 4,381), enabling prediction of both a genotype-based phenotype (88%) and tetrahydrobiopterin responsiveness (83%). This study shows that large genotype databases enable accurate phenotype prediction, allowing appropriate targeting of therapies to optimize clinical outcome.Fil: Hillert, Alicia. No especifΓ­ca;Fil: Anikster, Yair. No especifΓ­ca;Fil: Belanger Quintana, Amaya. No especifΓ­ca;Fil: Burlina, Alberto. No especifΓ­ca;Fil: Burton, Barbara K.. No especifΓ­ca;Fil: Carducci, Carla. No especifΓ­ca;Fil: Chiesa, Ana Elena. Consejo Nacional de Investigaciones CientΓ­ficas y TΓ©cnicas. Oficina de CoordinaciΓ³n Administrativa Parque Centenario. Centro de Investigaciones EndocrinolΓ³gicas "Dr. CΓ©sar Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones EndocrinolΓ³gicas "Dr. CΓ©sar Bergada". FundaciΓ³n de EndocrinologΓ­a Infantil. Centro de Investigaciones EndocrinolΓ³gicas "Dr. CΓ©sar Bergada"; ArgentinaFil: Christodoulou, John. No especifΓ­ca;Fil: Dordevic, Maja. No especifΓ­ca;Fil: Desviat, Lourdes R.. No especifΓ­ca;Fil: Eliyahu, Aviva. No especifΓ­ca;Fil: Evers, Roeland A.F.. No especifΓ­ca;Fil: Fajkusova, Lena. No especifΓ­ca;Fil: Feillet, Francois. No especifΓ­ca;Fil: Bonfim Freitas, Pedro E.. No especifΓ­ca;Fil: Gizewska, MarΓ­a. No especifΓ­ca;Fil: Gundorova, Polina. No especifΓ­ca;Fil: Karall, Daniela. No especifΓ­ca;Fil: Kneller, Katya. No especifΓ­ca;Fil: Kutsev, Sergey I.. No especifΓ­ca;Fil: Leuzzi, Vincenzo. No especifΓ­ca;Fil: Levy, Harvey L.. No especifΓ­ca;Fil: Lichter Koneck, Uta. No especifΓ­ca;Fil: Muntau, Ania C.. No especifΓ­ca;Fil: Namour, Fares. No especifΓ­ca;Fil: Oltarzewsk, Mariusz. No especifΓ­ca;Fil: Paras, Andrea. No especifΓ­ca;Fil: Perez, BelΓ©n. No especifΓ­ca;Fil: Polak, Emil. No especifΓ­ca;Fil: Polyakov, Alexander V.. No especifΓ­ca;Fil: Porta, Francesco. No especifΓ­ca;Fil: Rohrbach, Marianne. No especifΓ­ca;Fil: Scholl BΓΌrgi, Sabine. No especifΓ­ca;Fil: SpΓ©cola, Norma. No especifΓ­ca;Fil: Stojiljkovic, Maja. No especifΓ­ca;Fil: Shen, Nan. No especifΓ­ca;Fil: Santana da Silva, Luiz C.. No especifΓ­ca;Fil: Skouma, Anastasia. No especifΓ­ca;Fil: van Spronsen, Francjan. No especifΓ­ca;Fil: Stoppioni, Vera. No especifΓ­ca;Fil: ThΓΆny, Beat. No especifΓ­ca;Fil: Trefz, Friedrich K.. No especifΓ­ca;Fil: Vockley, Jerry. No especifΓ­ca;Fil: Yu, Youngguo. No especifΓ­ca;Fil: Zschocke, Johannes. No especifΓ­ca;Fil: Hoffmann, Georg F.. No especifΓ­ca;Fil: Garbade, Sven F.. No especifΓ­ca;Fil: Blau, Nenad. No especifΓ­ca

    Systematic documentation and analysis of human genetic variation in hemoglobinopathies using the microattribution approach

    Get PDF
    We developed a series of interrelated locus-specific databases to store all published and unpublished genetic variation related to hemoglobinopathies and thalassemia and implemented microattribution to encourage submission of unpublished observations of genetic variation to these public repositories. A total of 1,941 unique genetic variants in 37 genes, encoding globins and other erythroid proteins, are currently documented in these databases, with reciprocal attribution of microcitations to data contributors. Our project provides the first example of implementing microattribution to incentivise submission of all known genetic variation in a defined system. It has demonstrably increased the reporting of human variants, leading to a comprehensive online resource for systematically describing human genetic variation in the globin genes and other genes contributing to hemoglobinopathies and thalassemias. The principles established here will serve as a model for other systems and for the analysis of other common and/or complex human genetic diseases

    Quantitative Proteome Profiling of C. burnetii under Tetracycline Stress Conditions

    Get PDF
    The recommended antibiotic regimen against Coxiella burnetii, the etiological agent of Q fever, is based on a semi-synthetic, second-generation tetracycline, doxycycline. Here, we report on the comparison of the proteomes of a C. burnetii reference strain either cultured under control conditions or under tetracycline stress conditions. Using the MS-driven combined fractional diagonal chromatography proteomics technique, out of the 531 proteins identified, 5 and 19 proteins were found significantly up- and down-regulated respectively, under tetracycline stress. Although the predicted cellular functions of these regulated proteins did not point to known tetracycline resistance mechanisms, our data clearly reveal the plasticity of the proteome of C. burnetii to battle tetracycline stress. Finally, we raise several plausible hypotheses that could further lead to more focused experiments on studying tetracycline resistance in C. burnetii and thus reduced treatment failures of Q fever

    Edwardsiella Comparative Phylogenomics Reveal the New Intra/Inter-Species Taxonomic Relationships, Virulence Evolution and Niche Adaptation Mechanisms

    Get PDF
    Edwardsiella bacteria are leading fish pathogens causing huge losses to aquaculture industries worldwide. E. tarda is a broad-host range pathogen that infects more than 20 species of fish and other animals including humans while E. ictaluri is host-adapted to channel catfish causing enteric septicemia of catfish (ESC). Thus, these two species consist of a useful comparative system for studying the intricacies of pathogen evolution. Here we present for the first time the phylogenomic comparisons of 8 genomes of E. tarda and E. ictaluri isolates. Genome-based phylogenetic analysis revealed that E. tarda could be separate into two kinds of genotypes (genotype I, EdwGI and genotype II, EdwGII) based on the sequence similarity. E. tarda strains of EdwGI were clustered together with the E. ictaluri lineage and showed low sequence conservation to E. tarda strains of EdwGII. Multilocus sequence analysis (MLSA) of 48 distinct Edwardsiella strains also supports the new taxonomic relationship of the lineages. We identified the type III and VI secretion systems (T3SS and T6SS) as well as iron scavenging related genes that fulfilled the criteria of a key evolutionary factor likely facilitating the virulence evolution and adaptation to a broad range of hosts in EdwGI E. tarda. The surface structure-related genes may underlie the adaptive evolution of E. ictaluri in the host specification processes. Virulence and competition assays of the null mutants of the representative genes experimentally confirmed their contributive roles in the evolution/niche adaptive processes. We also reconstructed the hypothetical evolutionary pathway to highlight the virulence evolution and niche adaptation mechanisms of Edwardsiella. This study may facilitate the development of diagnostics, vaccines, and therapeutics for this under-studied pathogen
    • …
    corecore