In vitro prediction of stop-codon suppression by intravenous gentamicin in patients with cystic fibrosis: a pilot study

BACKGROUND: Cystic fibrosis (CF) is caused by mutations in the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR) protein, which acts as a chloride channel activated by cyclic AMP (cAMP). The most frequent mutation found in 70% of CF patients is F508del, while premature stop mutations are found in about 10% of patients. In vitro aminoglycoside antibiotics (e.g. gentamicin) suppress nonsense mutations located in CFTR permitting translation to continue to the natural termination codon. Pharmacologic suppression of stop mutations within the CFTR may be of benefit to a significant number of patients. Our pilot study was conducted to determine whether intravenous gentamicin suppresses stop codons in CF patients and whether it has clinical benefits. METHODS: A dual gene reporter system was used to determine the gentamicin-induced readthrough level of the most frequent stop mutations within the CFTR in the French population. We investigated readthrough efficiency in response to 10 mg/kg once-daily intravenous gentamicin perfusions in patients with and without stop mutations. Respiratory function, sweat chloride concentration, nasal potential difference (NPD) and CFTR expression in nasal epithelial cells were measured at baseline and after 15 days of treatment. RESULTS: After in vitro gentamicin incubation, the readthrough efficiency for the Y122X mutation was at least five times higher than that for G542X, R1162X, and W1282X. In six of the nine patients with the Y122X mutation, CFTR immunodetection showed protein at the membrane of the nasal epithelial cells and the CFTR-dependent Cl(- )secretion in NPD measurements increased significantly. Respiratory status also improved in these patients, irrespective of the gentamicin sensitivity of the bacteria present in the sputum. Mean sweat chloride concentration decreased significantly and normalised in two patients. Clinical status, NPD and sweat Cl(- )values did not change in the Y122X patients with no protein expression, in patients with the other stop mutations investigated in vitro and those without stop mutations. CONCLUSION: Suppression of stop mutations in the CFTR gene with parenteral gentamicin can be predicted in vitro and is associated with clinical benefit and significant modification of the CFTR-mediated Cl(- )transport in nasal and sweat gland epithelium

Synthetic Amorphous Silicon Dioxide (NM-200, NM-201, NM-202, NM-203, NM-204): Characterisation and Physico-Chemical Properties

The European Commission's Joint Research Centre (JRC) provides scientific support to European Union policy including nanotechnology. Within this context, the JRC launched, in February 2011, a repository for Representative Test Materials (RTMs), based on preparatory work started in 2008. It supports both EU and international research projects, and especially the OECD Working Party on Manufactured Nanomaterials (WPMN). The WPMN leads an exploratory testing programme "Testing a Representative set of Manufactured Nanomaterials" for the development and collection of data on characterisation, toxicological and ecotoxicological properties, as well as risk assessment and safety evaluation of nanomaterials. The purpose is to understand the applicability of the OECD Test Guidelines for the testing of nanomaterials as well as end-points relevant for such materials. The Repository responds to a need for nanosafety research purposes: availability of nanomaterial from a single production batch to enhance the comparability of results between different research laboratories and projects. The availability of representative nanomaterials to the international scientific community furthermore enhances and enables development of safe materials and products. The present report presents the physico-chemical characterisation of the synthetic amorphous silicon dioxide (SiO2, SAS) from the JRC repository: NM-200, NM-201, NM-202, NM-203 and NM-204. NM-200 was selected as principal material for the OECD test programme "Testing a representative set of manufactured nanomaterials". NM-200, NM-201 and NM-204 (precipitated SAS) are produced via the precipitation process, whereas NM-202 and NM-203 (fumed or pyrogenic SAS) are produced via a high temperature process. Each of these NMs originates from one respective batch of commercially manufactured SAS. They are nanostructured, i.e. they consist of aggregated primary particles. The SAS NMs may be used as a representative material in the measurement and testing with regard to hazard identification, risk and exposure assessment studies. The results for more than 15 endpoints are addressed in the present report, including physical-chemical properties, such as size and size distribution, crystallite size and electron microscopy images. Sample and test item preparation procedures are addressed. The results are based on studies by several European laboratories participating to the NANOGENOTOX Joint Action, as well as the JRC.JRC.I.4-Nanobioscience

Multi-walled Carbon Nanotubes, NM-400, NM-401, NM-402, NM-403: Characterisation and Physico-Chemical Properties

In 2011 the JRC launched a Repository for Representative Test Materials that supports both EU and international research projects, and especially the OECD Working Party on Manufactured Nanomaterials' (WPMN) exploratory testing programme "Testing a Representative set of Manufactured Nanomaterials" for the development and collection of data on characterisation, toxicological and ecotoxicological properties, as well as risk assessment and safety evaluation of nanomaterials. The JRC Repository responds to a need for availability of nanomaterial from a single production batch to enhance the comparability of results between different research laboratories and projects. The present report presents the physico-chemical characterisation of the multi-walled carbon nanotubes (MWCNT) from the JRC Repository: NM-400, NM-401, NM-402 and NM-403. NM-400 was selected as principal material for the OECD WPMN testing programme. They are produced by catalytic chemical vapour deposition. Each of these NMs originates from one respective batch of commercially manufactured MWCNT. They are nanostructured, i.e. they consist of more than one graphene layer stacked on each other and rolled together as concentric tubes. The MWCNT NMs may be used as a representative material in the measurement and testing with regard to hazard identification, risk and exposure assessment studies. The results are based on studies by several European laboratories participating to the NANOGENOTOX Joint Action.JRC.I.4-Nanobioscience

Titanium Dioxide, NM-100, NM-101, NM-102, NM-103, NM-104, NM-105: Characterisation and Physico-Chemical Properties

The European Commission's Joint Research Centre (JRC) provides scientific support to European Union policy including nanotechnology. Within this context, the JRC launched, in February 2011, a repository for Representative Test Materials (RTMs), based on preparatory work started in 2008. It supports both EU and international research projects, and especially the OECD Working Party on Manufactured Nanomaterials (WPMN). The WPMN leads an exploratory testing programme "Testing a Representative set of Manufactured Nanomaterials" for the development and collection of data on characterisation, toxicological and ecotoxicological properties, as well as risk assessment and safety evaluation of nanomaterials. The purpose is to understand the applicability of the OECD Test Guidelines for the testing of nanomaterials as well as end-points relevant for such materials. The Repository responds to a need for nanosafety research purposes: availability of nanomaterial from a single production batch to enhance the comparability of results between different research laboratories and projects. The availability of representative nanomaterials to the international scientific community furthermore enhances and enables development of safe materials and products. The present report presents the physico-chemical characterisation of the Titanium dioxide series from the JRC repository: NM-100, NM-101, NM-102, NM-103, NM-104 and NM-105. NM-105 was selected as principal material for the OECD test programme "Testing a representative set of manufactured nanomaterials". NM-100 is included in the series as a bulk comparator. Each of these NMs originates from one batch of commercially manufactured TiO2. The TiO2 NMs may be used as representative material in the measurement and testing with regard to hazard identification, risk and exposure assessment studies. The results for more than 15 endpoints are addressed in the present report, including physico-chemical properties, such as size and size distribution, crystallite size and electron microscopy images. Sample and test item preparation procedures are addressed. The results are based on studies by several European laboratories participating to the NANOGENOTOX Joint Action, as well as by the JRC.JRC.I.4-Nanobioscience

HBM4EU chromates study - Overall results and recommendations for the biomonitoring of occupational exposure to hexavalent chromium

Exposure to hexavalent chromium [Cr(VI)] may occur in several occupational activities, e.g., welding, Cr(VI) electroplating and other surface treatment processes. The aim of this study was to provide EU relevant data on occupational Cr(VI) exposure to support the regulatory risk assessment and decision-making. In addition, the capability and validity of different biomarkers for the assessment of Cr(VI) exposure were evaluated. The study involved nine European countries and involved 399 workers in different industry sectors with exposures to Cr(VI) such as welding, bath plating, applying or removing paint and other tasks. We also studied 203 controls to establish a background in workers with no direct exposure to Cr(VI). We applied a cross-sectional study design and used chromium in urine as the primary biomonitoring method for Cr(VI) exposure. Additionally, we studied the use of red blood cells (RBC) and exhaled breath condensate (EBC) for biomonitoring of exposure to Cr(VI). Personal measurements were used to study exposure to inhalable and respirable Cr(VI) by personal air sampling. Dermal exposure was studied by taking hand wipe samples. The highest internal exposures were observed in the use of Cr(VI) in electrolytic bath plating. In stainless steel welding the internal Cr exposure was clearly lower when compared to plating activities. We observed a high correlation between chromium urinary levels and air Cr(VI) or dermal total Cr exposure. Urinary chromium showed its value as a first approach for the assessment of total, internal exposure. Correlations between urinary chromium , Cr(VI) in EBC and Cr in RBC were low, probably due to differences in kinetics and indicating that these biomonitoring approaches may not be interchangeable but rather complementary. This study showed that occupational biomonitoring studies can be conducted successfully by multi-national collaboration and provide relevant information to support policy actions aiming to reduce occupational expo-sure to chemicals

Etude de la fraction argileuse de séquences sédimentaires de la Meuse et du Gard. Reconstitution de l'histoire diagénétique et des caractéristiques physico-chimiques des cibles.<br />Aspects minéralogiques, géochimiques et isotopiques.

Very low-permeable argillaceous rocks like Callovo-Oxfordian claystones or Vraconian siltstones werechosen to host a research laboratory built to determine the physico-chemical properties of the hostformations for a potential underground disposal of radioactive waste. Knowledge and understanding ofpost-sedimentary modifications are of prime importance for definition of these properties; evaluation and quantification of the post-sedimentary changes represent the aim of this study, focusedspecifically on the clay material of the sequences.Samples were taken from two drillings (HTM102 and MAR501). In the HTM102 core samples, illiteand mixed-layers illite/smectite are the dominant clay components of most clay fractions. SystematicSEM and TEM observations and isotopic K-Ar and Rb-Sr analyses pointed to diagenetic neoformations of carbonates (calcite, dolomite) and clays. For instance, veils and laths of authigenic clay particles around old detrital ones can distinctly be observed. The epoch, duration and extent of the diagenetic activity(ies) are difficult to evaluate because of an overall detrital contribution even in the finest granulometric fractions. However, analysis of a bentonite layer in the sequence provides a diagenetic reference for the authigenic clay material. Correlation between relative sea level and authigenesis of smectite-rich mineral has been outlined. Chemistry of diagenetic fluids also seems to be reliable with sea level variations. These observations argue in favour of diagenetic activities limited in restricted rock volumes.The case study of MAR501 is close to the HTM102 one: smectite-rich illite/smectite mixed-layersrepresent the major component of the clay fraction and K-Ar values argue in the sense of a mixingbetween detrital and younger clay populations. Diagenetic glauconites in the sequence yield an ageclose to 93,7±0,3Ma for Vraconian level, in agreement with stratigraphical data. The case study of aclay-filled fault within the sequence favors a confined-sequence behaviour. Indeed, no migrations ofelements and especially of REE took place during fluid flows, the clay minerals preserving theirgeochemical properties.All the results favor reliable confinment properties of the low-permeable argillaceous sequences.Les séquences argileuses peu perméables telles que les argilites callovo-oxfordiennes du bassin deParis ou les siltites vraconiennes du Gard, ont été choisies pour l'implantation éventuelle d'unlaboratoire souterrain destiné à tester les propriétés physico-chimiques de ces formations dansl'éventualité d'un stockage profond de déchets nucléaires. La connaissance et la compréhension desmodifications post-sédimentaires sont fondamentales dans la définition de ces propriétés. Le but duprésent travail visait donc à évaluer et quantifier ces changements par l'étude de ces roches, enparticulier des minéraux argileux.Les échantillons proviennent de deux forages (HTM102 et MAR501). Les principaux minérauxargileux dans le forage HTM102 sont l'illite et les interstratifiés illite/smectite. Les observations auMET et au MEB couplées aux analyses isotopiques K-Ar et Rb-Sr mettent en évidence la néoformation de carbonates (calcite, dolomite) et d'argiles. Celles-ci apparaissent au MET comme des particules authigènes lattées en croissance sur des particules détritiques. La durée et l'extension de ces événements diagénétiques sont difficiles à évaluer du fait d'une contamination systématique deséchantillons par une contribution détritique, et ce même dans les fractions les plus fines. Cependant,l'étude d'un niveau de bentonite dans la séquence permet de caler l'époque et la durée de ladiagenèse. En assimilant cette bentonite à un pôle authigène, il a été possible de reconstruire lesvariations des valeurs K-Ar de chaque fraction argileuse dans la séquence. Ainsi, la corrélationobservée entre les variations du niveau marin relatif et la formation d'un matériel argileux riche ensmectite d'une part, et des chimies de fluides différentes d'autre part, sont autant d'arguments enfaveur de réactions diagénétiques en système sinon clos du moins restreint.Les travaux sur le forage MAR501 sont comparables à ceux réalisés sur le forage HTM102, avecégalement un mélange entre deux populations argileuses d'âge différent. Les glauconitesdiagénétiques ont permis de caler le Vraconien au voisinage de 93,7 ± 0,3 Ma, en accord avec lesdonnées stratigraphiques. L'étude d'une fracture colmatée par une matrice essentiellement argileuseconfirme le caractère confiné de cette séquence. Aucune migration d'éléments, et en particulier deTR, n'a été mise en évidence lors de la circulation de paléofluides, indiquant que les minérauxargileux ont conservé leurs propriétés géochimiques.L'ensemble de ces résultats est en faveur de propriétés de confinement fiables dans le cas des deux séquences argileuses

Etude de la fraction argileuse de séquences sédimentaires de la Meuse et du Gard (reconstitution de l'histoire diagénétique et des caractéristiques physico-chimiques des cicles. Aspects minéralogiques, géochimiques et isotopiques)

Les séquences argileuses peu perméables telles que les argilites callovo-oxfordiennes du bassin de Paris ou les siltites vraconiennes du Gard, ont été choisies pour l'implantation éventuelle d'un laboratoire souterrain destiné à tester les propriétés physico-chimiques de ces formations dans l'éventualité d'un stockage profond de déchets nucléaires. La connaissance et la compréhension des modifications post-sédimentaires sont fondamentales dans la définition de ces propriétés. Le but du présent travail visait donc à évaluer et quantifier ces changements par l'étude de ces roches, en particulier des minéraux argileux. Les échantillons proviennent de deux forages (HTM102 et MAR501). Les principaux minéraux argileux dans le forage HTM102 sont l'illite et les interstratifiés illite/smectite. Les observations au MET et au MEB couplées aux analyses isotopiques K-Ar et Rb-Sr mettent en évidence la néoformation de carbonates (calcite, dolomite) et d'argiles. Celles-ci apparaissent au MET comme des particules authigènes lattées en croissance sur des particules détritiques. La durée et l'extension de ces événements diagénétiques sont difficiles à évaluer du fait d'une contamination systématique des échantillons par une contribution détritique, et ce même dans les fractions les plus fines. Cependant, l'étude d'un niveau de bentonite dans la séquence permet de caler l'époque et la durée de la diagenèse. En assimilant cette bentonite à un pôle authigène, il a été possible de reconstruire les variations des valeurs K-Ar de chaque fraction argileuse dans la séquence. Ainsi, la corrélation observée entre les variations du niveau marin relatif et la formation d'un matériel argileux riche en smectite d'une part, et des chimies de fluides différentes d'autre part, sont autant d'arguments en faveur de réactions diagénétiques en système sinon clos du moins restreint. Les travaux sur le forage MAR501 sont comparables à ceux réalisés sur le forage HTM102, avec également un mélange entre deux populations argileuses d'âge différent. Les glauconites diagénétiques ont permis de caler le Vraconien au voisinage de 93,7 +- 0,3Ma, en accord avec les données stratigraphiques.Very low-permeable argillaceous rocks like Callovo-Oxfordian claystones or Vraconian siltstones were chosen to host a research laboratory built to determine the physico-chemical properties of the host formations for a potential underground disposal of radioactive waste. Knowledge and understanding of post-sedimentary modifications are of prime importance for definition of these properties; evaluation and quantification of the post-sedimentary changes represent the aim of this study, focused specifically on the clay material of the sequences. Samples were taken from two drillings (HTM102 and MAR501). In the HTM102 core samples, illite and mixed-layers illite/smectite are the dominant clay components of most clay fractions. Systematic SEM and TEM observations and isotopic K-Ar and Rb-Sr analyses pointed to diagenetic neoformations of carbonates (calcite, dolomite) and clays. For instance, veils and laths of authigenic clay particles around old detrital ones can distinctly be observed. The epoch, duration and extent of the diagenetic activity(ies) are difficult to evaluate because of an overall detrital contribution even in the finest granulometric fractions. However, analysis of a bentonite layer in the sequence provides a diagenetic reference for the authigenic clay material. Correlation between relative sea level and authigenesis of smectite-rich mineral has been outlined. Chemistry of diagenetic fluids also seems to be reliable with sea level variations. These observations argue in favour of diagenetic activities limited in restricted rock volumes. The case study of MAR501 is close to the HTM102 one: smectite-rich illite/smectite mixed-layers represent the major component of the clay fraction and K-Ar values argue in the sense of a mixing between detrital and younger clay populations. Diagenetic glauconites in the sequence yield an age close to 93,7+-0,3Ma for Vraconian level, in agreement with stratigraphical data. The case study of a clay-filled fault within the sequence favors a confined-sequence behaviour. Indeed, no migrations of elements and especially of REE took place during fluid flows, the clay minerals preserving their geochemical properties. All the results favor reliable confinment properties of the low-permeable argillaceous sequences.STRASBOURG-Sc. et Techniques (674822102) / SudocSudocFranceF

Synthèse des données de mesurage en fibres courtes d’amiante obtenues dans le cadre de la campagne INRS pour la détermination des facteurs de protection assignés des appareils de protection respiratoire utilisés en chantier de désamiantage

The purpose of this campaign was to determine, by META analysis, the protection factors assigned to respiratory protective devices worn by asbestos removal operators during the process of removing asbestos-containing materials on level 2 and 3 sites, in accordance with the regulations in force. during the campaign. Even if this campaign focused on the measurement of so-called WHO fibers (length > 5 µm, diameter 3), an evaluation of the concentrations of short asbestos fibers (length 3) was also performed.This summary presents the main measurement results for short asbestos fibers from the campaign. It is based on the use of measurements taken on 6 level 3 asbestos removal sites and on 3 level 2 sites.Synthèse des données de mesurage en fibres courtes d'amiante obtenues dans le cadre de la campagne INRS pour la détermination des facteurs de protection assignés des appareils de protection respiratoire utilisés en chantier de désamiantage Synthèse des données de mesurage en fibres courtes d'amiante obtenues dans le cadre de la campagne INRS pour la détermination des facteurs de protection assignés des appareils de protection respiratoire utilisés en chantier de désamiantag

Synthèse des données de mesurage en fibres courtes d’amiante obtenues dans le cadre de la campagne INRS pour la détermination des facteurs de protection assignés des appareils de protection respiratoire utilisés en chantier de désamiantage

The purpose of this campaign was to determine, by META analysis, the protection factors assigned to respiratory protective devices worn by asbestos removal operators during the process of removing asbestos-containing materials on level 2 and 3 sites, in accordance with the regulations in force. during the campaign. Even if this campaign focused on the measurement of so-called WHO fibers (length > 5 µm, diameter 3), an evaluation of the concentrations of short asbestos fibers (length 3) was also performed.This summary presents the main measurement results for short asbestos fibers from the campaign. It is based on the use of measurements taken on 6 level 3 asbestos removal sites and on 3 level 2 sites.Synthèse des données de mesurage en fibres courtes d'amiante obtenues dans le cadre de la campagne INRS pour la détermination des facteurs de protection assignés des appareils de protection respiratoire utilisés en chantier de désamiantage Synthèse des données de mesurage en fibres courtes d'amiante obtenues dans le cadre de la campagne INRS pour la détermination des facteurs de protection assignés des appareils de protection respiratoire utilisés en chantier de désamiantag