46 research outputs found
Recurrent Campylobacter jejuni Infections with In Vivo Selection of Resistance to Macrolides and Carbapenems: Molecular Characterization of Resistance Determinants
We present two independent cases of recurrent multidrug-resistant Campylobacter jejuni infection in immunocompromised hosts and the clinical challenges encountered due to the development of high-level carbapenem resistance. The mechanisms associated with this unusual resistance for Campylobacters were characterized. Initial macrolide and carbapenem-susceptible strains acquired resistance to erythromycin (MIC . 256mg/L), ertapenem (MIC . 32mg/L), and meropenem (MIC . 32mg/L) during treatment. Carbapenem-resistant isolates developed an in-frame insertion resulting in an extra Asp residue in the major outer membrane protein PorA, within the extracellular loop L3 that connects b-strands 5 and 6 and forms a constriction zone involved in Ca21 binding. The isolates presenting the highest MIC to ertapenem exhibited an extra nonsynonymous mutation (G167AjGly56Asp) at PorA s extracellular loop L1. IMPORTANCE Carbapenem susceptibility patterns suggest drug impermeability, related to either insertion and/or single nucleotide polymorphism (SNP) within porA. Similar molecular events occurring in two independent cases support the association of these mechanisms with carbapenem resistance in Campylobacter spp
Recurrent Campylobacter jejuni Infections with In Vivo Selection of Resistance to Macrolides and Carbapenems: Molecular Characterization of Resistance Determinants
Erratum in: Microbiol Spectr. 2023 Dec 12;11(6):e0312123. doi: 10.1128/spectrum.03121-23. Epub 2023 Oct 10.Free PMC article: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10434052/We present two independent cases of recurrent multidrug-resistant
Campylobacter jejuni infection in immunocompromised hosts and the clinical challenges
encountered due to the development of high-level carbapenem resistance. The mechanisms
associated with this unusual resistance for Campylobacters were characterized.
Initial macrolide and carbapenem-susceptible strains acquired resistance to erythromycin
(MIC . 256mg/L), ertapenem (MIC . 32mg/L), and meropenem (MIC . 32mg/L) during
treatment. Carbapenem-resistant isolates developed an in-frame insertion resulting in an
extra Asp residue in the major outer membrane protein PorA, within the extracellular
loop L3 that connects b-strands 5 and 6 and forms a constriction zone involved in Ca21
binding. The isolates presenting the highest MIC to ertapenem exhibited an extra nonsynonymous
mutation (G167AjGly56Asp) at PorAâs extracellular loop L1.
IMPORTANCE Carbapenem susceptibility patterns suggest drug impermeability, related
to either insertion and/or single nucleotide polymorphism (SNP) within porA. Similar molecular
events occurring in two independent cases support the association of these
mechanisms with carbapenem resistance in Campylobacter spp.Importance: Carbapenem susceptibility patterns suggest drug impermeability, related to either insertion and/or single nucleotide polymorphism (SNP) within porA. Similar molecular events occurring in two independent cases support the association of these mechanisms with carbapenem resistance in Campylobacter spp.This work was partially supported by GenomePT (ref. POCI-01-0145-FEDER-022184)
from Fundação para a CiĂȘncia e Tecnologia, Portugal.info:eu-repo/semantics/publishedVersio
Sub-surface geology and velocity structure of the Krafla high temperature geothermal field, Iceland : Integrated ditch cuttings, wireline and zero offset vertical seismic profile analysis
The research leading to these results has received funding from the European Community's Seventh Framework Programme under grant agreement No. 608553 (Project IMAGE). The VMAPP project run by VBPR, DougalEARTH Ltd. and TGS also contributed funding to the borehole characterization of the K-18 borehole. Landsvirkun is acknowledged for their effort and assistance in this work and in particular for allowing the use of the data from well K-18. We further acknowledge the support from the Research Council of Norway through its Centres of Excellence funding scheme, project 22372 (SP and DAJ).Peer reviewedPostprin
An autosomal recessive leucoencephalopathy with ischemic stroke, dysmorphic syndrome and retinitis pigmentosa maps to chromosome 17q24.2-25.3
Background
Single-gene disorders related to ischemic stroke seem to be an important cause of stroke in young patients without known risk factors. To identify new genes responsible of such diseases, we studied a consanguineous Moroccan family with three affected individuals displaying hereditary leucoencephalopathy with ischemic stroke, dysmorphic syndrome and retinitis pigmentosa that appears to segregate in autosomal recessive pattern.
Methods
All family members underwent neurological and radiological examinations. A genome wide search was conducted in this family using the ABI PRISM linkage mapping set version 2.5 from Applied Biosystems. Six candidate genes within the region linked to the disease were screened for mutations by direct sequencing.
Results
Evidence of linkage was obtained on chromosome 17q24.2-25.3. Analysis of recombination events and LOD score calculation suggests linkage of the responsible gene in a genetic interval of 11 Mb located between D17S789 and D17S1806 with a maximal multipoint LOD score of 2.90. Sequencing of seven candidate genes in this locus, ATP5H, FDXR, SLC25A19, MCT8, CYGB, KCNJ16 and GRIN2C, identified three missense mutations in the FDXR gene which were also found in a homozygous state in three healthy controls, suggesting that these variants are not disease-causing mutations in the family.
Conclusion
A novel locus for leucoencephalopathy with ischemic stroke, dysmorphic syndrome and retinitis pigmentosa has been mapped to chromosome 17q24.2-25.3 in a consanguineous Moroccan family
Ophthalmic Artery Chemosurgery for Less Advanced Intraocular Retinoblastoma: Five Year Review
BACKGROUND: Ophthalmic artery chemosurgery (OAC) for retinoblastoma was introduced by us 5 years ago for advanced intraocular retinoblastoma. Because the success was higher than with existing alternatives and systemic side effects limited we have now treated less advanced intraocular retinoblastoma (Reese-Ellsworth (RE) I-III and International Classification Retinoblastoma (ICRB) B and C). METHODOLOGY/PRINCIPAL FINDINGS: Retrospective review of 5 year experience in eyes with Reese Ellsworth (Table 1) I (7 eyes), II (6 eyes) or III (6 eyes) and/or International Classification (Table 2) B (19 eyes) and C (11 eyes) treated with OAC (melphalan with or without topotecan) introduced directly into the ophthalmic artery. Patient survival was 100%. Ocular event-free survival was 100% for Reese-Ellsworth Groups I, II and III (and 96% for ICRB B and C) at a median of 16 months follow-up. One ICRB Group C (Reese-Ellsworth Vb) eye could not be treated on the second attempt for technical reasons and was therefore enucleated. No patient required a port and only one patient required transfusion of blood products. The electroretinogram (ERG) was unchanged or improved in 14/19 eyes. CONCLUSIONS/SIGNIFICANCE: Ophthalmic artery chemosurgery for retinoblastoma that was Reese-Ellsworth I, II and III (or International Classification B or C) was associated with high success (100% of treatable eyes were retained) and limited toxicity with results that equal or exceed conventional therapy with less toxicity
Very low neighbourhood income limits participation post stroke: preliminary evidence from a cohort study
Petrophysical, Geochemical, and Hydrological Evidence for Extensive Fracture-Mediated Fluid and Heat Transport in the Alpine Fault's Hanging-Wall Damage Zone
International audienceFault rock assemblages reflect interaction between deformation, stress, temperature, fluid, and chemical regimes on distinct spatial and temporal scales at various positions in the crust. Here we interpret measurements made in the hangingâwall of the Alpine Fault during the second stage of the Deep Fault Drilling Project (DFDPâ2). We present observational evidence for extensive fracturing and high hangingâwall hydraulic conductivity (âŒ10â9 to 10â7 m/s, corresponding to permeability of âŒ10â16 to 10â14 m2) extending several hundred meters from the fault's principal slip zone. Mud losses, gas chemistry anomalies, and petrophysical data indicate that a subset of fractures intersected by the borehole are capable of transmitting fluid volumes of several cubic meters on time scales of hours. DFDPâ2 observations and other data suggest that this hydrogeologically active portion of the fault zone in the hangingâwall is several kilometers wide in the uppermost crust. This finding is consistent with numerical models of earthquake rupture and offâfault damage. We conclude that the mechanically and hydrogeologically active part of the Alpine Fault is a more dynamic and extensive feature than commonly described in models based on exhumed faults. We propose that the hydrogeologically active damage zone of the Alpine Fault and other large active faults in areas of high topographic relief can be subdivided into an inner zone in which damage is controlled principally by earthquake rupture processes and an outer zone in which damage reflects coseismic shaking, strain accumulation and release on interseismic timescales, and inherited fracturing related to exhumation
The Helicobacter pylori Genome Project : insights into H. pylori population structure from analysis of a worldwide collection of complete genomes
Helicobacter pylori, a dominant member of the gastric microbiota, shares co-evolutionary history with humans. This has led to the development of genetically distinct H. pylori subpopulations associated with the geographic origin of the host and with differential gastric disease risk. Here, we provide insights into H. pylori population structure as a part of the Helicobacter pylori Genome Project (HpGP), a multi-disciplinary initiative aimed at elucidating H. pylori pathogenesis and identifying new therapeutic targets. We collected 1011 well-characterized clinical strains from 50 countries and generated high-quality genome sequences. We analysed core genome diversity and population structure of the HpGP dataset and 255 worldwide reference genomes to outline the ancestral contribution to Eurasian, African, and American populations. We found evidence of substantial contribution of population hpNorthAsia and subpopulation hspUral in Northern European H. pylori. The genomes of H. pylori isolated from northern and southern Indigenous Americans differed in that bacteria isolated in northern Indigenous communities were more similar to North Asian H. pylori while the southern had higher relatedness to hpEastAsia. Notably, we also found a highly clonal yet geographically dispersed North American subpopulation, which is negative for the cag pathogenicity island, and present in 7% of sequenced US genomes. We expect the HpGP dataset and the corresponding strains to become a major asset for H. pylori genomics
Modularity Of An Odd Icosahedral Representation
. In this paper, we prove that the representation from GQ in GL 2 (C ) with image A 5 corresponding to the example 16 in [B-K] is modular. This representation, with conductor 5203 and determinant 43 , does not satisfy the hypothesis of the main theorem of [B-D-SB-T]. Indeed, if and are the eigenvalues of the Frobenius element Frob ;2 in 2, then = has order 5. 1. Introduction Consider an irreducible Galois representation : GQ ! GL 2 (C ) and the corresponding induced projective representation : GQ ! PGL 2 (C ); where we denote by Q an algebraic closure of Q and by GQ =Gal(Q =Q) the absolute Galois group over Q . Artin has conjectured (for any nontrival irreducible representation : GQ ! GL n (C )), that the analytic continuation of the L-series associated to the representation is an entire function. It is known by results of Hecke, Langlands and Tunnel ([Lan], [Tun]) that satises Artin's conjecture, if Im() is solvable. If Im() is isomorphic to A 5 , this con..