RESUMEN
Coagulase-negative staphylococci (CoNS) for a long time were considered avirulent constituents of the human and warm-blooded animal microbiota. However, at present, S. epidermidis, S. haemolyticus, and S. hominis are recognized as opportunistic pathogens. Although linezolid is not registered for the treatment of CoNS infections, it is widely used off-label, promoting emergence of resistance. Bioinformatic analysis based on maximum-likelihood phylogeny and Bayesian clustering of the CoNS genomes obtained in the current study and downloaded from public databases revealed the existence of international linezolid-resistant lineages, each of which probably had a common predecessor. Linezolid-resistant S. epidermidis sequence-type (ST) 2 from Russia, France, and Germany formed a compact group of closely related genomes with a median pairwise single nucleotide polymorphism (SNP) difference of fewer than 53 SNPs, and a common ancestor of this lineage appeared in 1998 (1986-2006) before introduction of linezolid in practice. Another compact group of linezolid-resistant S. epidermidis was represented by ST22 isolates from France and Russia with a median pairwise SNP difference of 40; a common ancestor of this lineage appeared in 2011 (2008-2013). Linezolid-resistant S. hominis ST2 from Russia, Germany, and Brazil also formed a group with a high-level genome identity with median 25.5 core-SNP differences; the appearance of the common progenitor dates to 2003 (1996-2012). Linezolid-resistant S. hominis isolates from Russia demonstrated associated resistance to teicoplanin. Analysis of a midpoint-rooted phylogenetic tree of the group confirmed the genetic proximity of Russian and German isolates; Brazilian isolates were phylogenetically distant. repUS5-like plasmids harboring cfr were detected in S. hominis and S. haemolyticus.
RESUMEN
In this study, we identified the relationship between the genetic lineage of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) sequence type 22 (ST22) from Russia and other regions. Sixty ST22 isolates from Russia were characterised through whole-genome sequencing. To evaluate the phylogenetic relationship of Russian isolates with the global ST22 population, we analysed 1283 genomes obtained from NCBI's GenBank. The phylogenetic tree of the ST22 global population consisted of three main clusters (A, B and C). The first (cluster A) was represented by EMRSA-15 isolates, the second (cluster B) by heterogeneous isolates from different regions harbouring different sets of virulence genes, and the third (cluster C) by isolates from the Middle East previously recognised as 'Gaza clone' and similar isolates from Russia. Presence of the toxic shock syndrome toxin (tsst) and elastin-binding protein S (ebpS) genes as well as the hypothetical proteins NCTC13616_00051 and NCTC13616_00047 were the most useful factors in discriminating ST22 lineages. Although the CA-MRSA 'Gaza clone' was mainly recovered from carriers, its widespread occurrence is a cause for concern. Differentiation of the 'Gaza clone' from other MRSA lineages is necessary for planning infection control measures.
Asunto(s)
Genoma Bacteriano , Staphylococcus aureus Resistente a Meticilina/genética , Infecciones Estafilocócicas/microbiología , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Toxinas Bacterianas/genética , Portador Sano/microbiología , Infecciones Comunitarias Adquiridas/microbiología , Farmacorresistencia Bacteriana/genética , Enterotoxinas/genética , Genes Bacterianos , Humanos , Staphylococcus aureus Resistente a Meticilina/clasificación , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Medio Oriente , Filogenia , Polimorfismo de Nucleótido Simple , Federación de Rusia , Superantígenos/genética , Secuenciación Completa del GenomaRESUMEN
Candida auris is an emergent yeast pathogen, easily transmissible between patients and with high percent of multidrug resistant strains. Here we present a draft genome sequence of the first known Russian strain of C. auris, isolated from a case of candidemia. The strain clustered within South Asian C. auris clade and seemingly represented an independent event of dissemination from the original species range. Observed fluconazole resistance was probably due to F105L and K143R mutations in ERG11.
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Candida/genética , Farmacorresistencia Fúngica/genética , Genoma Fúngico , Antifúngicos/farmacología , Candida/efectos de los fármacos , Candida/aislamiento & purificación , Candidemia/microbiología , Fluconazol/farmacología , Humanos , Pruebas de Sensibilidad Microbiana , Mutación , Filogenia , Federación de Rusia , Secuenciación Completa del GenomaAsunto(s)
Antibacterianos/farmacología , Resistencia a las Cefalosporinas , Cefalosporinas/farmacología , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Infecciones Estafilocócicas/microbiología , Humanos , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Federación de Rusia , CeftarolinaRESUMEN
The aim of this study was to investigate the patterns of antimicrobial resistance and molecular features of methicillin-resistant Staphylococcus aureus (MRSA) isolates in Russia. Isolates recovered from hospital patients (n=480), healthy medical personnel (n=25), and healthy carriers (n=13) were included in the study. Hospital-acquired MRSA (HA-MRSA) demonstrated high resistance to ciprofloxacin, gentamicin, and chloramphenicol (76%-92%), moderate - to tetracycline, erythromycin, clindamycin, and rifampicin (38%-54%), and low - to fusidic acid, co-trimoxazole, mupirocin, and daptomycin (2%-7%). Elevated MIC (2.0µg/ml) of vancomycin was detected in 26% of isolates. All isolates were susceptible to linezolid and tigecycline. Multilocus sequence typing (MLST) revealed that CC8 isolates (ST8+ST239) constituted 83.1% of HA-MRSA and that this genetic lineage dominated in all regions from Krasnoyarsk to Saint Petersburg. A local ST239 variant harboring the tst gene (ST239Kras) was detected in Krasnoyarsk. The other HA-MRSA isolates belonged to clonal complex 5 (CC5) (21 isolates, 12.2%) and CC22 (2, 1.2%). The majority of CC5 isolates were affiliated with sequence type 228 (ST228) and were characterized with decreased susceptibility to ceftaroline (MIC=2µg/ml). We also detected, for the first time in Russia, livestock-associated MRSA (LA-MRSA) from clusters CC398 and CC97 in humans. Among the 2053 healthy persons screened for nasal carriage of S. aureus, the bacteria were isolated from 426 (21%); among them, 13 carried isolates identified as community-associated MRSA (CA-MRSA). Eleven of 13 CA-MRSA isolates belonged to ST22 (spa types t223, t3243, and t3689; SCCmec types IVa and IVc, agr type I, tst-positive) and were similar to the EMRSA-15/Middle Eastern variant (Gaza strain).
Asunto(s)
Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple/genética , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/genética , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Aminoglicósidos/farmacología , Cloranfenicol/farmacología , Infección Hospitalaria , Femenino , Fluoroquinolonas/farmacología , Humanos , Masculino , Staphylococcus aureus Resistente a Meticilina/clasificación , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Epidemiología Molecular , Tipificación de Secuencias Multilocus , Federación de Rusia/epidemiología , Infecciones Estafilocócicas/microbiología , Tetraciclinas/farmacología , beta-Lactamas/farmacologíaRESUMEN
PURPOSE: To identify the effects of adding two different doses of dexamethasone on the duration and quality of interscalene block in patients undergoing shoulder surgery in ambulatory surgery settings. METHODS: The study design was reviewed and approved by the University at Buffalo Institutional Review Board for Human Subjects. After obtaining informed consent, a total of 90 patients undergoing shoulder surgery using interscalene block with 0.5% bupivacaine (40 mL) were assigned randomly to one of three groups: control patients, "Group C," who received no additive; low dose, "Group L," who received additional dexamethasone 4 mg; and high dose, "Group H," who received dexamethasone 8 mg in addition to 0.5% bupivacaine. Postoperative analgesia was assessed using the numeric rating scores of pain and the postoperative consumption of acetaminophen 325 mg + hydrocodone 7.5 mg tablets. Analysis was by intention to treat. Statistical significance was tested using a two-way analysis of variance and a nonparametric analysis of variance for consumption of analgesics. RESULTS: Four patients were excluded from the study due to either a failed block or inadequate follow-up. The duration of analgesia was significantly prolonged in both Group L (21.6 ± 2.4 h) and Group H (25.2 ± 1.9 h) compared with Group C (13.3 ± 1.0 h) (p < 0.05). Similarly, the duration of motor block was longer in both Group L (36.7 ± 4.1 h), and Group H (39.2 ± 3.9 h) compared to Group C (24.6 ± 3.3 h) (p < 0.05). Postoperative analgesic consumption for the first 48 h was significantly lower in Group L (6.5 [4-8] tabs) and in Group H (5.5 [4-7] tabs) vs. 9.5 [8-12] tabs in Group C (p < 0.01). There were no adverse events related to dexamethasone during the 4-week follow-up period. CONCLUSION: The addition of dexamethasone to bupivacaine significantly prolonged the duration of the motor block and improved the quality of analgesia following interscalene block. There was no difference in the duration of analgesia and motor block between low-dose and high-dose dexamethasone.
Asunto(s)
Adyuvantes Anestésicos/administración & dosificación , Anestésicos Locales/uso terapéutico , Antiinflamatorios/uso terapéutico , Bupivacaína/administración & dosificación , Dexametasona/administración & dosificación , Bloqueo Nervioso/métodos , Dolor Postoperatorio/tratamiento farmacológico , Procedimientos Quirúrgicos Ambulatorios/métodos , Analgesia/métodos , Relación Dosis-Respuesta a Droga , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Hombro/cirugía , Estadísticas no ParamétricasRESUMEN
The present study investigates the suitability of direct bacterial profiling as a tool for the identification and subtyping of pathogenic Neisseria. The genus Neisseria includes two human pathogens, Neisseria meningitidis and Neisseria gonorrhoeae, as well as several nonpathogenic Neisseria species. Here, a matrix-assisted laser desorption/ionization time-of-flight mass spectrometry profiling protocol was optimized using a laboratory strain of E. coli DH5alpha to guarantee high quality and reproducible results. Subsequently, mass spectra for both laboratory and clinical strains of N. gonorrhoeae, N. meningitidis, and several nonpathogenic Neisseria species were collected. Significant interspecies differences but little intraspecies diversity were revealed by means of a visual inspection and bioinformatics examination using the MALDI BioTyper software. Cluster analysis successfully separated mass spectra collected from three groups that corresponded to N. gonorrhoeae, N. meningitidis, and nonpathogenic Neisseria isolates. Requiring only one bacterial colony for testing and using a fast and easy measuring protocol, this approach represents a powerful tool for the rapid identification of pathogenic Neisseria and can be adopted for other microorganisms.
Asunto(s)
Técnicas de Tipificación Bacteriana , Neisseria/aislamiento & purificación , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Análisis por Conglomerados , Escherichia coli , Femenino , Humanos , Masculino , Neisseria/clasificación , Neisseria/genética , Neisseria/patogenicidadRESUMEN
Three strains of a novel Bartonella species (Bartonella tamiae) were isolated from human patients from Thailand. Sequence analysis of six chromosomal regions (16S rRNA, gltA, groEL, ftsZ, rpoB, and the intergenic spacer region) and phenotypical analysis supported the similarity of the three strains and placed them within the genus Bartonella separately from previously described species.