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1.
Enferm Infecc Microbiol Clin (Engl Ed) ; 41(5): 290-293, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36681574

RESUMEN

INTRODUCTION: Neisseria meningitidis is associated with invasive infections causing high mortality rates. The objective of this study was to describe the population structure of Colombian invasive isolates with ST-9493, a potentially emerging clonal group in the country. METHODS: The complete genomes of 34 invasive isolates of serogroup B with ST-9493 and its variants at one or two loci were sequenced by Illumina to describe the phenotypic and genotypic characteristics of these isolates. RESULTS: The relationship of a clonal group associated with ST-136 CC41/44 was phylogenetically established, identifying two main clades composed of isolates from an outbreak or endemic. The most frequent alleles and peptides included porA 17, porB 44, fHbp 2.24, NHBA 10, and the FetA F5-17 variant. Most of the isolates were susceptible to the antibiotics evaluated. CONCLUSION: This study shows that meningococcal isolates with ST-9493 are an autochthonous clonal group with population dynamics and the capacity to cause endemic and epidemic meningococcal disease in Colombia.


Asunto(s)
Infecciones Meningocócicas , Neisseria meningitidis , Humanos , Neisseria meningitidis/genética , Colombia/epidemiología , Infecciones Meningocócicas/epidemiología , Serogrupo , Genotipo
2.
Microorganisms ; 10(10)2022 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-36296278

RESUMEN

Mine tailings are produced by mining activities and contain diverse heavy metal ions, which cause environmental problems and have negative impacts on ecosystems. Different microorganisms, including yeasts, play important roles in the absorption and/or adsorption of these heavy metal ions. This work aimed to analyze proteins synthesized by the yeast Yarrowia lipolytica AMJ6 (Yl-AMJ6), isolated from Andean mine tailings in Peru and subjected to stress conditions with common heavy metal ions. Yeast strains were isolated from high Andean water samples impacted by mine tailings from Yanamate (Pasco, Peru). Among all the isolated yeasts, the Yl-AMJ6 strain presented LC50 values of 1.06 mM, 1.42 mM, and 0.49 mM for the Cr+6, Cu+2, and Cd+2 ions, respectively. Proteomic analysis of theYl-AMJ6 strain under heavy metal stress showed that several proteins were up- or downregulated. Biological and functional analysis of these proteins showed that they were involved in the metabolism of proteins, nucleic acids, and carbohydrates; response to oxidative stress and protein folding; ATP synthesis and ion transport; membrane and cell wall; and cell division. The most prominent proteins that presented the greatest changes were related to the oxidative stress response and carbohydrate metabolism, suggesting the existence of a defense mechanism in these yeasts to resist the impact of environmental contamination by heavy metal ions.

3.
Microorganisms, v. 10, 2002, out. 2022
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-4661

RESUMEN

Mine tailings are produced by mining activities and contain diverse heavy metal ions, which cause environmental problems and have negative impacts on ecosystems. Different microorganisms, including yeasts, play important roles in the absorption and/or adsorption of these heavy metal ions. This work aimed to analyze proteins synthesized by the yeast Yarrowia lipolytica AMJ6 (Yl-AMJ6), isolated from Andean mine tailings in Peru and subjected to stress conditions with common heavy metal ions. Yeast strains were isolated from high Andean water samples impacted by mine tailings from Yanamate (Pasco, Peru). Among all the isolated yeasts, the Yl-AMJ6 strain presented LC50 values of 1.06 mM, 1.42 mM, and 0.49 mM for the Cr+6, Cu+2, and Cd+2 ions, respectively. Proteomic analysis of theYl-AMJ6 strain under heavy metal stress showed that several proteins were up- or downregulated. Biological and functional analysis of these proteins showed that they were involved in the metabolism of proteins, nucleic acids, and carbohydrates; response to oxidative stress and protein folding; ATP synthesis and ion transport; membrane and cell wall; and cell division. The most prominent proteins that presented the greatest changes were related to the oxidative stress response and carbohydrate metabolism, suggesting the existence of a defense mechanism in these yeasts to resist the impact of environmental contamination by heavy metal ions.

4.
Clin Infect Dis ; 73(Suppl_4): S290-S299, 2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-34850835

RESUMEN

BACKGROUND: Carbapenem-resistant Klebsiella pneumoniae (CRKP) is an emerging public health problem. This study explores the specifics of CRKP epidemiology in Colombia based on whole genome sequencing (WGS) of the National Reference Laboratory at Instituto Nacional de Salud (INS)'s 2013-2017 sample collection. METHODS: A total of 425 CRKP isolates from 21 departments were analyzed by HiSeq-X10®Illumina high-throughput sequencing. Bioinformatic analysis was performed, primarily using the pipelines developed collaboratively by the National Institute for Health Research Global Health Research Unit (GHRU) on Genomic Surveillance of Antimicrobial Resistance (AMR), and AGROSAVIA. RESULTS: Of the 425 CRKP isolates, 91.5% were carbapenemase-producing strains. The data support a recent expansion and the endemicity of CRKP in Colombia with the circulation of 7 high-risk clones, the most frequent being CG258 (48.39% of isolates). We identified genes encoding carbapenemases blaKPC-3, blaKPC-2, blaNDM-1, blaNDM-9, blaVIM-2, blaVIM-4, and blaVIM-24, and various mobile genetic elements (MGE). The virulence of CRKP isolates was low, but colibactin (clb3) was present in 25.2% of isolates, and a hypervirulent CRKP clone (CG380) was reported for the first time in Colombia. ST258, ST512, and ST4851 were characterized by low levels of diversity in the core genome (ANI > 99.9%). CONCLUSIONS: The study outlines complex CRKP epidemiology in Colombia. CG258 expanded clonally and carries specific carbapenemases in specific MGEs, while the other high-risk clones (CG147, CG307, and CG152) present a more diverse complement of carbapenemases. The specifics of the Colombian situation stress the importance of WGS-based surveillance to monitor evolutionary trends of sequence types (STs), MGE, and resistance and virulence genes.


Asunto(s)
Infecciones por Klebsiella , Klebsiella pneumoniae , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Carbapenémicos/farmacología , Colombia/epidemiología , Genómica , Humanos , Infecciones por Klebsiella/epidemiología , Klebsiella pneumoniae/genética , Pruebas de Sensibilidad Microbiana , Secuenciación Completa del Genoma , beta-Lactamasas/genética
5.
Infect Genet Evol ; 95: 105038, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34403832

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genetic diversity has the potential to impact the virus transmissibility and the escape from natural infection- or vaccine-elicited neutralizing antibodies. Here, representative samples from circulating SARS-CoV-2 in Colombia between January and April 2021, were processed for genome sequencing and lineage determination following the nanopore amplicon ARTIC network protocol and PANGOLIN pipeline. This strategy allowed us to identify the emergence of the B.1.621 lineage, considered a variant of interest (VOI) with the accumulation of several substitutions affecting the Spike protein, including the amino acid changes I95I, Y144T, Y145S and the insertion 146 N in the N-terminal domain, R346K, E484K and N501Y in the Receptor binding Domain (RBD) and P681H in the S1/S2 cleavage site of the Spike protein. The rapid increase in frequency and fixation in a relatively short time in Magdalena, Atlantico, Bolivar, Bogotá D.C, and Santander that were near the theoretical herd immunity suggests an epidemiologic impact. Further studies will be required to assess the biological and epidemiologic roles of the substitution pattern found in the B.1.621 lineage.


Asunto(s)
Sustitución de Aminoácidos , COVID-19/epidemiología , Genoma Viral , Mutación , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus/genética , COVID-19/transmisión , COVID-19/virología , Colombia/epidemiología , Monitoreo Epidemiológico , Evolución Molecular , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Filogenia , Filogeografía , Dominios Proteicos , SARS-CoV-2/clasificación , SARS-CoV-2/patogenicidad , Índice de Severidad de la Enfermedad
6.
Front Med (Lausanne) ; 8: 697605, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34262921

RESUMEN

COVID-19 pandemics has led to genetic diversification of SARS-CoV-2 and the appearance of variants with potential impact in transmissibility and viral escape from acquired immunity. We report a new and highly divergent lineage containing 21 distinctive mutations (10 non-synonymous, eight synonymous, and three substitutions in non-coding regions). The amino acid changes L249S and E484K located at the CTD and RBD of the Spike protein could be of special interest due to their potential biological role in the virus-host relationship. Further studies are required for monitoring the epidemiologic impact of this new lineage.

7.
PLoS One ; 15(7): e0234475, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32663215

RESUMEN

BACKGROUND: Neisseria meningitidis is a significant cause of morbidity and mortality worldwide. Meningococcal isolates have a highly dynamic population structure and can be phenotypically and genetically differentiated into serogroups and clonal complexes. The aim of this study was to describe the phenotypic and genotypic characteristics of invasive isolates recovered in Colombia from 2013 to 2016. METHODOLOGY: A total of 193 invasive isolates were analyzed. Phenotypic and genotypic characteristics were determined by serotyping, antimicrobial susceptibility testing, pulsed-field gel electrophoresis (PFGE) and whole-genome sequencing. RESULTS: Based on the results, meningococcal serogroups C, B and Y were responsible for 47.9%, 41.7%, and 9.4% of cases, respectively, and the distribution of serogroups B and C changed over time. Fifteen clonal groups and 14 clonal complexes (cc) were identified by PFGE and genome sequencing. The main clonal group included serogroup B isolates with sequence type (ST)-9493 and its four single-locus variants, which has only been identified in Colombian isolates. The clonal population structure demonstrates that the isolates in this study mainly belong to four clonal complexes: ST-11 cc, ST-32 cc, ST-35 cc and ST-41/44 cc. Thirty-eight penA alleles were identified, but no correlation between MICs and specific sequences was observed. CONCLUSION: This study shows that most meningococcal isolates recovered from patients with invasive meningococcal disease in Colombia are strains associated with distinct globally disseminated hyperinvasive clones.


Asunto(s)
Infecciones Meningocócicas/epidemiología , Infecciones Meningocócicas/genética , Neisseria meningitidis/genética , Adolescente , Adulto , Técnicas de Tipificación Bacteriana/métodos , Niño , Preescolar , Colombia/epidemiología , Electroforesis en Gel de Campo Pulsado/métodos , Femenino , Genotipo , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Neisseria meningitidis/aislamiento & purificación , Neisseria meningitidis/patogenicidad , Serogrupo , Serotipificación
8.
Agora USB ; 17(2): 427-440, jul.-dic. 2017. graf
Artículo en Español | LILACS | ID: biblio-886605

RESUMEN

Resumen El conflicto armado en Colombia en el Siglo XXI no puede entenderse independientemente del Plan Colombia, en este sentido este acuerdo de cooperación se ha transformado, con sus pros y contras, en elemento central del conflicto en el país, abriendo la puerta a que haya un papel más activo de la comunidad internacional en el mismo. La cooperación militar internacional ha jugado un papel en el conflicto armado interno colombiano


Abstract The armed conflict in Colombia in the 21st century cannot be understood independently of the Colombia Plan. In this sense, this cooperation agreement has become, with its pros and cons, a key element of the conflict in the country, opening the door to have a more active role of the international community in it. International military cooperation has played a role in the Colombian internal armed conflict.

9.
Proteins ; 69(3): 581-94, 2007 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-17623845

RESUMEN

Flavodoxins, noncovalent complexes between apoflavodoxins and flavin mononucleotide (FMN), are useful models to investigate the mechanism of protein/flavin recognition. In this respect, the only available crystal structure of an apoflavodoxin (that from Anabaena) showed a closed isoalloxazine pocket and the presence of a bound phosphate ion, which posed many questions on the recognition mechanism and on the potential physiological role exerted by phosphate ions. To address these issues we report here the X-ray structure of the apoflavodoxin from the pathogen Helicobacter pylori. The protein naturally lacks one of the conserved aromatic residues that close the isoalloxazine pocket in Anabaena, and the structure has been determined in a medium lacking phosphate. In spite of these significant differences, the isoallozaxine pocket in H. pylori apoflavodoxin appears also closed and a chloride ion is bound at a native-like FMN phosphate site. It seems thus that it is a general characteristic of apoflavodoxins to display closed, non-native, isoalloxazine binding sites together with native-like, rather promiscuous, phosphate binding sites that can bear other available small anions present in solution. In this respect, both binding energy hot spots of the apoflavodoxin/FMN complex are initially unavailable to FMN binding and the specific spot for FMN recognition may depend on the dynamics of the two candidate regions. Molecular dynamics simulations show that the isoalloxazine binding loops are intrinsically flexible at physiological temperatures, thus facilitating the intercalation of the cofactor, and that their mobility is modulated by the anion bound at the phosphate site.


Asunto(s)
Apoproteínas/química , Mononucleótido de Flavina/química , Flavodoxina/química , Helicobacter pylori/química , Anabaena/química , Aniones/química , Apoproteínas/efectos de los fármacos , Sitios de Unión , Cristalografía por Rayos X , Flavodoxina/efectos de los fármacos , Modelos Moleculares , Análisis de Componente Principal , Unión Proteica , Conformación Proteica , Proteínas Recombinantes/química
10.
Bogotá, D.C; s.n; 1995. 123 p. tab, graf.
Tesis en Español | LILACS | ID: lil-190283

RESUMEN

En la historia de la humanidad la violencia ha jugado un papel importante en las diferentes etapas del desarrollo del hombre. Entre los factores más importantes que se asocian están el sexo, la edad, la ocupación, los acontecimientos del momento y la ingesta de alcohol entre otros. En este estudio se escogieron por muestreo aleatorio 151 reportes de personas fallecidas en el mes de Diciembre de 1.992 (tomadas del Instituto de Medicina Legal y Ciencias Forenses de Santafé de Bogotá, D.C). Se analizaron diferentes variables que asocian la muerte violenta con la ingesta de alcohol en un porcentaje del 23.8 por ciento que es ligeramente menor al reportado en el estudio realizado en Diciembre de 1.993 que fue del 36.6 por ciento.


Asunto(s)
Alcoholismo , Violencia
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