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1.
Tuberculosis (Edinb) ; 133: 102171, 2022 03.
Article in English | MEDLINE | ID: mdl-35101846

ABSTRACT

The TB Portals program is an international collaboration for the collection and dissemination of tuberculosis data from patient cases focused on drug resistance. The central database is a patient-oriented resource containing both patient and pathogen clinical and genomic information. Herein we provide a summary of the pathogen genomic data available through the TB Portals and show one potential application by examining patterns of genomic pairwise distances. Distributions of pairwise distances highlight overall patterns of genome variability within and between Mycobacterium tuberculosis phylogenomic lineages. Closely related isolates (based on whole-genome pairwise distances and time between sample collection dates) from different countries were identified as potential evidence of international transmission of drug-resistant tuberculosis. These high-level views of genomic relatedness provide information that can stimulate hypotheses for further and more detailed research.


Subject(s)
Mycobacterium tuberculosis , Tuberculosis, Multidrug-Resistant , Tuberculosis , Antitubercular Agents/therapeutic use , Databases, Factual , Drug Resistance, Multiple, Bacterial/genetics , Genomics , Humans , Microbial Sensitivity Tests , Mycobacterium tuberculosis/genetics , Tuberculosis/diagnosis , Tuberculosis/drug therapy , Tuberculosis, Multidrug-Resistant/diagnosis , Tuberculosis, Multidrug-Resistant/drug therapy , Tuberculosis, Multidrug-Resistant/genetics
2.
mBio ; 12(5): e0270821, 2021 10 26.
Article in English | MEDLINE | ID: mdl-34700378

ABSTRACT

The Cryptococcus gattii species complex has often been referred to as a primary pathogen due to its high infection frequency among apparently immunocompetent patients. In order to scrutinize the immune status of patients and the lineages of etiologic agents, we analyzed patient histories and the molecular types of etiologic agents from 135 global C. gattii cases. Eighty-six of 135 patients had been diagnosed as immunocompetent, although some of them had underlying medical issues, and 49 were diagnosed as immunocompromised with risk factors similar to those seen in Cryptococcus neoformans infection. We focused on the 86 apparently immunocompetent patients and were able to obtain plasma from 32 (37%) to analyze for the presence of autoantibodies against the granulocyte-macrophage colony-stimulating factor (GM-CSF) since these antibodies have been reported as a hidden risk factor for C. gattii infection. Among the 32 patients, 25 were free from any known other health issues, and 7 had various medical conditions at the time of diagnosis for cryptococcosis. Importantly, plasma from 19 (76%) of 25 patients with no recognized underlying medical condition showed the presence of GM-CSF autoantibodies, supporting this antibody as a major hidden risk factor for C. gattii infection. These data indicate that seemingly immunocompetent people with C. gattii infection warrant detailed evaluation for unrecognized immunologic risks. There was no relationship between molecular type and underlying conditions of patients. Frequency of each molecular type was related to its geographic origin exemplified by the overrepresentation of VGIV in HIV-positive (HIV+) patients due to its prevalence in Africa. IMPORTANCE The C. neoformans and C. gattii species complex causes cryptococcosis. The C. neoformans species complex is known as an opportunistic pathogen since it primarily infects immunocompromised patients. C. gattii species complex has been referred to as a primary pathogen due to its high infection frequency in apparently immunocompetent people. We analyzed 135 global cases of C. gattii infection with documented patient history. Eighty-six of 135 patients were originally diagnosed as immunocompetent and 49 as immunosuppressed with similar underlying conditions reported for C. neoformans infection. A significant number of C. gattii patients without known underlying conditions possessed autoantibodies against granulocytes-macrophage colony-stimulating factor (GM-CSF) in their plasma, supporting the presence of GM-CSF antibodies as a hidden risk factor for C. gattii infection. No relationship was found between C. gattii lineages and the underlying conditions except for overrepresentation of the molecular type VGIV among HIV+ patients due to the prevalence of VGIV in Africa.


Subject(s)
Cryptococcosis/etiology , Cryptococcus gattii/pathogenicity , Opportunistic Infections/etiology , Opportunistic Infections/microbiology , Africa/epidemiology , Autoantibodies/blood , Autoantibodies/immunology , Cryptococcosis/immunology , Cryptococcosis/microbiology , Cryptococcus gattii/classification , Cryptococcus gattii/genetics , Cryptococcus gattii/immunology , HIV Infections/complications , HIV Infections/epidemiology , Humans , Immunocompetence , Immunocompromised Host , Opportunistic Infections/immunology , Risk Factors
3.
J Transl Med ; 17(1): 43, 2019 02 11.
Article in English | MEDLINE | ID: mdl-30744658

ABSTRACT

BACKGROUND: Sequence information generated from next generation sequencing is often computationally phased using haplotype-phasing algorithms. Utilizing experimentally derived allele or haplotype information improves this prediction, as routinely used in HLA typing. We recently established a large dataset of long ERMAP alleles, which code for protein variants in the Scianna blood group system. We propose the phylogeny of this set of 48 alleles and identify evolutionary steps to derive the observed alleles. METHODS: The nucleotide sequence of > 21 kb each was used for all physically confirmed 48 ERMAP alleles that we previously published. Full-length sequences were aligned and variant sites were extracted manually. The Bayesian coalescent algorithm implemented in BEAST v1.8.3 was used to estimate a coalescent phylogeny for these variants and the allelic ancestral states at the internal nodes of the phylogeny. RESULTS: The phylogenetic analysis allowed us to identify the evolutionary relationships among the 48 ERMAP alleles, predict 4243 potential ancestral alleles and calculate a posterior probability for each of these unobserved alleles. Some of them coincide with observed alleles that are extant in the population. CONCLUSIONS: Our proposed strategy places known alleles in a phylogenetic framework, allowing us to describe as-yet-undiscovered alleles. In this new approach, which relies heavily on the accuracy of the alleles used for the phylogenetic analysis, an expanded set of predicted alleles can be used to infer alleles when large genotype data are analyzed, as typically generated by high-throughput sequencing. The alleles identified by studies like ours may be utilized in designing of microarray technologies, imputing of genotypes and mapping of next generation sequencing data.


Subject(s)
Alleles , Base Pairing/genetics , Phylogeny , Algorithms , Bayes Theorem , Blood Group Antigens/genetics , Butyrophilins/genetics , Genotype , Humans , Reproducibility of Results
4.
J Clin Microbiol ; 55(2): 457-469, 2017 02.
Article in English | MEDLINE | ID: mdl-27903602

ABSTRACT

The emergence and spread of drug-resistant Mycobacterium tuberculosis (DR-TB) are critical global health issues. Eastern Europe has some of the highest incidences of DR-TB, particularly multidrug-resistant (MDR) and extensively drug-resistant (XDR) TB. To better understand the genetic composition and evolution of MDR- and XDR-TB in the region, we sequenced and analyzed the genomes of 138 M. tuberculosis isolates from 97 patients sampled between 2010 and 2013 in Minsk, Belarus. MDR and XDR-TB isolates were significantly more likely to belong to the Beijing lineage than to the Euro-American lineage, and known resistance-conferring loci accounted for the majority of phenotypic resistance to first- and second-line drugs in MDR and XDR-TB. Using a phylogenomic approach, we estimated that the majority of MDR-TB was due to the recent transmission of already-resistant M. tuberculosis strains rather than repeated de novo evolution of resistance within patients, while XDR-TB was acquired through both routes. Longitudinal sampling of M. tuberculosis from 34 patients with treatment failure showed that most strains persisted genetically unchanged during treatment or acquired resistance to fluoroquinolones. HIV+ patients were significantly more likely to have multiple infections over time than HIV- patients, highlighting a specific need for careful infection control in these patients. These data provide a better understanding of the genomic composition, transmission, and evolution of MDR- and XDR-TB in Belarus and will enable improved diagnostics, treatment protocols, and prognostic decision-making.


Subject(s)
Evolution, Molecular , Genome, Bacterial , Mycobacterium tuberculosis/genetics , Sequence Analysis, DNA , Tuberculosis, Multidrug-Resistant/microbiology , Antitubercular Agents/pharmacology , Disease Transmission, Infectious , Genotype , Humans , Longitudinal Studies , Molecular Epidemiology , Republic of Belarus/epidemiology , Tuberculosis, Multidrug-Resistant/epidemiology , Tuberculosis, Multidrug-Resistant/transmission
5.
Emerg Infect Dis ; 22(2): 331-4, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26812583

ABSTRACT

Rapid sequencing of RNA/DNA from pathogen samples obtained during disease outbreaks provides critical scientific and public health information. However, challenges exist for exporting samples to laboratories or establishing conventional sequencers in remote outbreak regions. We successfully used a novel, pocket-sized nanopore sequencer at a field diagnostic laboratory in Liberia during the current Ebola virus outbreak.


Subject(s)
Ebolavirus/genetics , Hemorrhagic Fever, Ebola/microbiology , Nanopores , Sequence Analysis, DNA/methods , Disease Outbreaks , Genome, Viral , Hemorrhagic Fever, Ebola/epidemiology , Humans , Mutation
6.
Emerg Infect Dis ; 21(3): 460-3, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25695188

ABSTRACT

We conducted phylogeographic modeling to determine the introduction and spread of Guaroa virus in South America. The results suggest a recent introduction of this virus into regions of Peru and Bolivia over the past 60-70 years and emphasize the need for increased surveillance in surrounding areas.


Subject(s)
Bunyaviridae Infections/epidemiology , Bunyaviridae Infections/virology , Evolution, Molecular , Orthobunyavirus/classification , Orthobunyavirus/genetics , Phylogeny , Phylogeography , Bunyaviridae Infections/transmission , Geography , Humans , Molecular Typing , South America/epidemiology , Spatio-Temporal Analysis
7.
Nat Methods ; 4(10): 839-41, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17873888

ABSTRACT

We developed a rapid, economical method for high-resolution quantitative trait locus (QTL) mapping using microarrays for selective genotyping of pooled DNA samples. We generated 21,207 F2 flies from two inbred Drosophila melanogaster strains with known QTLs affecting lifespan, and hybridized DNA pools of young and old flies to microarrays. We used changes of gene frequency of 2,326 single-feature polymorphisms (SFPs) to map previously identified and additional QTLs affecting lifespan.


Subject(s)
Gene Expression Profiling/methods , Oligonucleotide Array Sequence Analysis/methods , Quantitative Trait Loci , Animals , Drosophila melanogaster/genetics , Drosophila melanogaster/growth & development , Female , Longevity/genetics , Male , Polymorphism, Genetic/genetics
8.
J Biol Chem ; 277(3): 2065-72, 2002 Jan 18.
Article in English | MEDLINE | ID: mdl-11689563

ABSTRACT

We studied the role of the matrix metalloproteinase gelatinase B (gelB; MMP-9) in epithelial regeneration using the gelB-deficient mouse. We report the novel finding that, in contrast to other MMPs expressed at the front of the advancing epithelial sheet in wounds of cornea, skin, or trachea, gelB acts to inhibit the rate of wound closure. We determined this to be due to control of cell replication, a novel capacity for MMPs not previously described. We also found that gelB delays the inflammatory response. Acceleration of these processes in gelB-deficient mice is correlated with a delay in signal transduction through Smad2, a transcription factor that inhibits cell proliferation, and in accumulation of epithelial-associated interleukin-1alpha, a cytokine that inhibits Smad2 signaling and promotes the inflammatory response. GelB-deficient mice also reveal defects in remodeling of extracellular matrix at the epithelial basement membrane zone, in particular, failure to effectively remove the fibrin(ogen) provisional matrix. We conclude that gelB coordinates and effects multiple events involved in the process of epithelial regeneration.


Subject(s)
Cornea/cytology , Matrix Metalloproteinase 9/metabolism , Wound Healing , Animals , Basement Membrane , Cornea/enzymology , DNA-Binding Proteins/metabolism , Epithelial Cells/cytology , Epithelial Cells/enzymology , Inflammation/enzymology , Inflammation/pathology , Matrix Metalloproteinase 9/genetics , Mice , Mice, Knockout , Regeneration , Smad2 Protein , Trans-Activators/metabolism
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