RESUMEN

BACKGROUND: Characteristics of non-clinical strains of methicillin-resistant Staphylococcus aureus (MRSA) especially from fishery environment are poorly understood. This research, in addition to comprehensive characterisation, sought to delineate the genetic relatedness between the MRSA strains originating from clinical as well as non-clinical settings. Out of 39 methicillin-resistant staphylococcal isolates from 197 fish samples, 6 (Three each of methicillin-resistant S. haemolyticus (MRSH) and MRSA) with distinct resistance profiles were selected for whole-genome sequencing. Using respective bioinformatics tools, MRSA genomes were comprehensively characterized for resistome, virulomes, molecular epidemiology and phylogenetic analysis. Simultaneously, MRSH genomes were specifically examined to characterize antimicrobial resistance genes (ARGs), owing to the fact that MRSH is often recognized as a reservoir for resistance determinants. RESULTS: Three MRSA clones identified in this study include ST672-IVd/t13599 (sequence type-SCCmec type/spa type), ST88-V/t2526, and ST672-IVa/t1309. Though, the isolates were phenotypically vancomycin-sensitive, five of the six genomes carried vancomycin resistance genes including the VanT (VanG cluster) or VanY (VanM cluster). Among the three MRSA, only one harbored the gene encoding Panton-Valentine Leukocidin (PVL) toxin, while staphylococcal enterotoxin (SEs) genes such as sea and seb, associated with staphylococcal food poisoning were identified in two other MRSA. Genomes of MRSH carried a composite of type V staphylococcal cassette chromosome mec (SCCmec) elements (5C2 & 5). This finding may be explained by the inversion and recombination events that may facilitate the integration of type V elements to the SCC elements of S. aureus with a methicillin-susceptible phenotype. Phylogenetically, MRSA from a non-clinical setting displayed a considerable relatedness to that from clinical settings. CONCLUSION: This study highlights the genetic diversity and resistance profiles of MRSA and MRSH, with non-clinical MRSA showing notable relatedness to clinical strains. Future research should explore resistance gene transfer mechanisms and environmental reservoirs to better manage MRSA spread.

Asunto(s)

Peces , Genoma Bacteriano , Staphylococcus aureus Resistente a Meticilina , Filogenia , Intoxicación Alimentaria Estafilocócica , Staphylococcus aureus Resistente a Meticilina/genética , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Staphylococcus aureus Resistente a Meticilina/patogenicidad , Animales , Peces/microbiología , Intoxicación Alimentaria Estafilocócica/microbiología , Genoma Bacteriano/genética , Antibacterianos/farmacología , Secuenciación Completa del Genoma , Virulencia/genética , Pruebas de Sensibilidad Microbiana , Humanos , Factores de Virulencia/genética , Alimentos Marinos/microbiología , Microbiología de Alimentos , Toxinas Bacterianas/genética , Epidemiología Molecular , Staphylococcus haemolyticus/genética , Staphylococcus haemolyticus/efectos de los fármacos , Staphylococcus haemolyticus/aislamiento & purificación , Staphylococcus haemolyticus/patogenicidad

RESUMEN

Staphylococci are classified as one of the pathogens causing bovine mastitis that can pose not only an economic loss to the dairy farms, but a serious public-health threat based on their zoonotic potential. We focused to monitor phenotypes of the isolated strains of Staphylococcus aureus (S. aureus) and Staphylococcus haemolyticus (S. haemolyticus) from milk of cows with clinical mastitis, including antibiotic resistance, biofilm forming ability and the presence of biofilm- and toxin- related genes. From a total of 191 milk samples were identified as S. aureus - 12% (22 isolates) and S. haemolyticus - 6% (12 isolates). Automatic interpreted reading of the antibiogram evaluated potentially 12 isolates as methicillin-resistant S. aureus and methicillin-resistant coagulase-negative Staphylococci. Genotypically, the isolates were positive for blaZ and negative for mecA and mecC. Others important mechanisms were inducible macrolide-lincosamide-streptogramin B (iMLSB) resistance with presence of msrA, ermC, vgaA. The most detected biofilm-associated and toxins genes were clfA, sdrD, sdrE, fnbpB, bbp, isdA, isdB, hla and see. S. aureus isolates were subjected to spa typing. It turned out that despite the strains coming from different farms, they were either resistant or sensitive to antibiotic, were all of the same spa-type t 10035. Our findings revealed the presence iMLSB, which, to our best knowledge, were described in Slovakian bovine staphylococci rarely. The majority of isolates were multidrug-resistant and carried multiple virulence genes, posing a potential public-health risk.

Asunto(s)

Antibacterianos , Biopelículas , Mastitis Bovina , Infecciones Estafilocócicas , Staphylococcus aureus , Staphylococcus haemolyticus , Animales , Bovinos , Mastitis Bovina/microbiología , Femenino , Staphylococcus haemolyticus/efectos de los fármacos , Staphylococcus haemolyticus/genética , Staphylococcus haemolyticus/aislamiento & purificación , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/genética , Infecciones Estafilocócicas/veterinaria , Infecciones Estafilocócicas/microbiología , Biopelículas/efectos de los fármacos , Antibacterianos/farmacología , Leche/microbiología , Pruebas de Sensibilidad Microbiana/veterinaria , Farmacorresistencia Bacteriana/genética

RESUMEN

Staphylococcus haemolyticus is a cause of bovine mastitis, leading to inflammation in the mammary gland. This bacterial infection adversely affects animal health, reducing milk quality and yield. Its emergence has been widely reported, representing a significant economic loss for dairy farms. Interestingly, S. haemolyticus exhibits higher levels of antimicrobial resistance than other coagulase-negative Staphylococci. In this study, we synthesized silver/silver chloride nanoparticles (Ag/AgCl-NPs) using Solanum lasiocarpum root extract and evaluated their antibacterial and antibiofilm activities against S. haemolyticus. The formation of the Ag/AgCl-NPs was confirmed using UV-visible spectroscopy, which revealed maximum absorption at 419 nm. X-ray diffraction (XRD) analysis demonstrated the crystalline nature of the Ag/AgCl-NPs, exhibiting a face-centered cubic lattice. Fourier transform infrared (FT-IR) spectroscopy elucidated the functional groups potentially involved in the Ag/AgCl-NPs synthesis. Transmission electron microscopy (TEM) analysis revealed that the average particle size of the Ag/AgCl-NPs was 10 nm. Antimicrobial activity results indicated that the minimum inhibitory concentration (MIC) and maximum bactericidal concentration (MBC) of the Ag/AgCl-NPs treatment were 7.82-15.63 µg/mL towards S. haemolyticus. Morphological changes in bacterial cells treated with the Ag/AgCl-NPs were observed under scanning electron microscopy (SEM). The Ag/AgCl-NPs reduced both the biomass of biofilm formation and preformed biofilm by approximately 20.24-94.66 % and 13.67-88.48 %. Bacterial viability within biofilm formation and preformed biofilm was reduced by approximately 21.56-77.54 % and 18.9-71.48 %, respectively. This study provides evidence of the potential of the synthesized Ag/AgCl-NPs as an antibacterial and antibiofilm agent against S. haemolyticus.

Asunto(s)

Antibacterianos , Biopelículas , Mastitis Bovina , Nanopartículas del Metal , Pruebas de Sensibilidad Microbiana , Extractos Vegetales , Raíces de Plantas , Compuestos de Plata , Plata , Solanum , Staphylococcus haemolyticus , Animales , Extractos Vegetales/farmacología , Extractos Vegetales/química , Antibacterianos/farmacología , Antibacterianos/química , Plata/farmacología , Plata/química , Biopelículas/efectos de los fármacos , Compuestos de Plata/farmacología , Compuestos de Plata/química , Bovinos , Mastitis Bovina/microbiología , Mastitis Bovina/tratamiento farmacológico , Raíces de Plantas/química , Nanopartículas del Metal/química , Staphylococcus haemolyticus/efectos de los fármacos , Femenino , Solanum/química , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Microscopía Electrónica de Transmisión

RESUMEN

An emergence of multidrug-resistant (MDR) Staphylococcus haemolyticus has been observed in the neonatal intensive care unit (NICU) of Nîmes University Hospital in southern France. A case-control analysis was conducted on 96 neonates, to identify risk factors associated with S. haemolyticus infection, focusing on clinical outcomes. Forty-eight MDR S. haemolyticus strains, isolated from neonates between October 2019 and July 2022, were investigated using routine in vitro procedures and whole-genome sequencing. Additionally, five S. haemolyticus isolates from adult patients were sequenced to identify clusters circulating within the hospital environment. The incidence of neonatal S. haemolyticus was significantly associated with low birth weight, lower gestational age, and central catheter use (p < 0.001). Sepsis was the most frequent clinical manifestation in this series (20/46, 43.5%) and was associated with five deaths. Based on whole-genome analysis, three S. haemolyticus genotypes were predicted: ST1 (6/53, 11%), ST25 (3/53, 5.7%), and ST29 (44/53, 83%), which included the subcluster II-A, predominantly emerging in the neonatal department. All strains were profiled in silico to be resistant to methicillin, erythromycin, aminoglycosides, and fluoroquinolones, consistent with in vitro antibiotic susceptibility tests. Moreover, in silico prediction of biofilm formation and virulence-encoding genes supported the association of ST29 with severe clinical outcomes, while the persistence in the NICU could be explained by the presence of antiseptic and heavy metal resistance-encoding genes. The clonality of S. haemolyticus ST29 subcluster II-A isolates confirms healthcare transmission causing severe infections. Based on these results, reinforced hygiene measures are necessary to eradicate the nosocomial transmission of MDR strains.

Asunto(s)

Antibacterianos , Farmacorresistencia Bacteriana Múltiple , Unidades de Cuidado Intensivo Neonatal , Infecciones Estafilocócicas , Staphylococcus haemolyticus , Secuenciación Completa del Genoma , Humanos , Staphylococcus haemolyticus/genética , Staphylococcus haemolyticus/efectos de los fármacos , Staphylococcus haemolyticus/aislamiento & purificación , Staphylococcus haemolyticus/clasificación , Francia/epidemiología , Recién Nacido , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/epidemiología , Farmacorresistencia Bacteriana Múltiple/genética , Femenino , Masculino , Antibacterianos/farmacología , Estudios de Casos y Controles , Pruebas de Sensibilidad Microbiana , Infección Hospitalaria/microbiología , Infección Hospitalaria/epidemiología , Genotipo , Factores de Riesgo , Genoma Bacteriano

RESUMEN

Elucidating the mechanisms of bacterial translocation is crucial for the prevention and treatment of neonatal sepsis. In the present study, we aimed to evaluate the potential of lactoferrin to inhibit the development of late-onset blood infection in neonates. Our investigation evaluates the role of key stress factors leading to the translocation of intestinal bacteria into the bloodstream and, consequently, the development of life-threatening sepsis. Three stress factors, namely weaning, intraperitoneal administration of Gram-positive cocci and oral intake of Gram-negative rods, were found to act synergistically. We developed a novel model of rat pups sepsis induced by bacterial translocation and observed the inhibition of this process by supplementation of various forms of lactoferrin: iron-depleted (apolactoferrin), iron-saturated (hololactoferrin) and manganese-saturated lactoferrin. Additionally, lactoferrin saturated with manganese significantly increases the Lactobacillus bacterial population, which contributes to the fortification of the intestinal barrier and inhibits the translocation phenomenon. The acquired knowledge can be used to limit the development of sepsis in newborns in hospital neonatal intensive care units.

Asunto(s)

Traslocación Bacteriana/efectos de los fármacos , Escherichia coli , Microbioma Gastrointestinal/efectos de los fármacos , Lactoferrina/administración & dosificación , Sepsis Neonatal/prevención & control , Staphylococcus haemolyticus , Animales , Animales Recién Nacidos , Apoproteínas/administración & dosificación , Infecciones de Transmisión Sanguínea/microbiología , Infecciones de Transmisión Sanguínea/prevención & control , Temperatura Corporal , Peso Corporal , Infección Hospitalaria/prevención & control , Modelos Animales de Enfermedad , Esquema de Medicación , Escherichia coli/efectos de los fármacos , Escherichia coli/fisiología , Microbioma Gastrointestinal/fisiología , Humanos , Recién Nacido , Masculino , Manganeso/administración & dosificación , Sepsis Neonatal/diagnóstico , Sepsis Neonatal/microbiología , Permeabilidad , Distribución Aleatoria , Ratas , Ratas Wistar , Staphylococcus haemolyticus/efectos de los fármacos , Staphylococcus haemolyticus/fisiología , Destete

RESUMEN

Introduction: Staphylococcus haemolyticus is an acquired opportunistic pathogen causing nosocomial infections. Our previous studies of S. haemolyticus showed a group of isolates that produced a significantly higher disease severity than the others. Further molecular typing showed that the sequence type (ST) 42 was the major clone among the isolates. The main aim of this study was to characterize ST42. Materials and Methods: Sixty-one and 36 isolates were collected from burn and nonburn patients, respectively. Molecular typing, antibiotic susceptibility assays, and phenotypic characterizations were performed. Results: Thirteen STs, including seven new STs, were established (ST42 to ST48). ST42 was prevalent in burn and nonburn patients, and all the pulsotype C isolates were ST42. Four of the novel STs originated from ST3, suggesting that these clonal lineages evolved locally. ST3 and ST42 showed a significant difference in clindamycin susceptibility; molecular typing showed only one MLST locus variation among seven loci in SH1431, which has been reportedly involved in the regulation of biofilm formation through Zn 2+ binding affinities. Conclusions: Seven novel S. haemolyticus STs were identified; phylogenetic analysis suggested the presence of locally evolved clonal lineages. The predominant ST42 showed weak biofilm formation abilities; other factors that cause the clonal lineage change still need further investigation.

Asunto(s)

Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple/genética , Staphylococcus haemolyticus/efectos de los fármacos , Staphylococcus haemolyticus/genética , Genes Bacterianos , Humanos , Pruebas de Sensibilidad Microbiana , Taiwán/epidemiología

RESUMEN

Due to their richness of bioactive substances, rose hips are a valuable raw material for obtaining extracts with potential antimicrobial activity. The aim of the study was to determine the antagonistic potential of whole pseudo-fruit and flesh extracts of three Rosa sp. varieties against Staphylococcus spp. bacteria isolated as food contaminants. The biological material in this study consisted of seven strains of bacteria from the genus Staphylococcus. Two strains-Staphylococcus aureus ATCC 25923 and Staphylococcus epidermidis DSMZ 3270-were used as reference strains. The other five strains were food-derived isolates-S. epidermidis A5, S. xylosus M5, S. haemolyticus M6, S. capitis KR6, and S. warneri KR2A. The material was the pseudo-fruits of Rosa canina, Rosa pomifera Karpatia, and Rosa rugosa. The polyphenols were extracted from the fleshy part and the whole pseudo-fruit for all rose varieties. The tested preparations differed significantly in their polyphenol composition. The sum of polyphenols ranged from 28 862 to 35 358 mg/100 g of lyophilisate. The main groups of polyphenols found in the preparations were flavanols and ellagitannins. All of the tested extracts inhibited the growth of staphylococci at a concentration of 500 mg/mL. Rosa rugosa fruit extract showed the strongest antimicrobial properties among the studied extracts. For all the strains, the growth inhibition had a diameter of 20.3-29.0 mm. Moreover, six out of the seven tested strains showed the highest inhibition with the use of this extract. The MIC of rose extracts was in the range of 3.125-500 mg/mL and was strictly dependent on the bacterial species, the species of the rose, and the part of the fruit from which the extract was obtained. Correlations were assessed between the main groups of polyphenols in the extracts and their inhibition of bacterial growth. In the case of pseudo-fruit extracts, the inhibitory effect on bacterial growth positively correlated with the content of ellagitannins, and this effect was observed for almost all the tested strains. The results presented herein follow the current trend of minimising the use of chemical preservatives in food; from this point of view, rose extracts are very promising.

Asunto(s)

Antibacterianos/química , Flavonoides/química , Taninos Hidrolizables/química , Polifenoles/química , Rosa/química , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Flavonoides/aislamiento & purificación , Flavonoides/farmacología , Contaminación de Alimentos/prevención & control , Microbiología de Alimentos/métodos , Frutas/química , Humanos , Taninos Hidrolizables/aislamiento & purificación , Taninos Hidrolizables/farmacología , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/química , Polifenoles/aislamiento & purificación , Polifenoles/farmacología , Staphylococcus/efectos de los fármacos , Staphylococcus/crecimiento & desarrollo , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrollo , Staphylococcus capitis/efectos de los fármacos , Staphylococcus capitis/crecimiento & desarrollo , Staphylococcus epidermidis/efectos de los fármacos , Staphylococcus epidermidis/crecimiento & desarrollo , Staphylococcus haemolyticus/efectos de los fármacos , Staphylococcus haemolyticus/crecimiento & desarrollo

RESUMEN

Bacteriocins are ribosomally-synthesized antimicrobial peptides, showing great potential as novel treatment options for multidrug-resistant pathogens. In this study, we designed a novel hybrid bacteriocin, Hybrid 1 (H1), by combing the N-terminal part and the C-terminal part of the related bacteriocins enterocin K1 (K1) and enterocin EJ97 (EJ97), respectively. Like the parental bacteriocins, H1 used the membrane-bound protease RseP as receptor, however, it differed from the others in the inhibition spectrum. Most notably, H1 showed a superior antimicrobial effect towards Staphylococcus haemolyticus-an important nosocomial pathogen. To avoid strain-dependency, we further evaluated H1 against 27 clinical and commensal S. haemolyticus strains, with H1 indeed showing high activity towards all strains. To curtail the rise of resistant mutants and further explore the potential of H1 as a therapeutic agent, we designed a bacteriocin-based formulation where H1 was used in combination with the broad-spectrum bacteriocins micrococcin P1 and garvicin KS. Unlike the individual bacteriocins, the three-component combination was highly effective against planktonic cells and completely eradicated biofilm-associated S. haemolyticus cells in vitro. Most importantly, the formulation efficiently prevented development of resistant mutants as well. These findings indicate the potential of a bacteriocins-based formulation as a treatment option for S. haemolyticus.

Asunto(s)

Bacteriocinas/farmacología , Biopelículas/efectos de los fármacos , Staphylococcus haemolyticus/fisiología , Secuencia de Aminoácidos , Antiinfecciosos/farmacología , Bacteriocinas/química , Farmacorresistencia Bacteriana/efectos de los fármacos , Farmacorresistencia Bacteriana/genética , Genes Bacterianos , Pruebas de Sensibilidad Microbiana , Modelos Biológicos , Mutación/genética , Staphylococcus haemolyticus/efectos de los fármacos , Staphylococcus haemolyticus/genética , Secuenciación Completa del Genoma

RESUMEN

The reactions of 2,4-bis(4-methoxyphenyl)-1,3-dithio-2,4-diphosphetane-2,4-disulfide (Lawesson's Reagent, LR) with benzylamine (BzNH2) and 4-phenylbutylamine (PhBuNH2) yield benzylammonium P-(4-methoxyphenyl)-N-benzyl-amidodithiophosphonate (BzNH3)(BzNH-adtp) and 4-phenylbutylammonium P-(4-methoxyphenyl)-N-(4-phenylbutyl)-amidodithiophosphonate (PhBuNH3)(PhBuNH-adtp). The relevant nickel complexes [Ni(BzNH-adtp)2] and [Ni(PhBuNH-adtp)2] and the corresponding hydrolysed derivatives (BzNH3)2[Ni(dtp)2] and (PhBuNH3)2[Ni(dtp)2] were prepared and fully characterized. The antimicrobial activity of the aforementioned amidodithiophosphonates against a set of Gram-positive and Gram-negative pathogen bacteria was evaluated, and [Ni(BzNH-adtp)2] and [Ni(PhBuNH-adtp)2] showed antiproliferative activity towards Staphylococcus aureus and Staphylococcus haemolyticus strains. density functional theory (DFT) calculations were performed to shed some light on the activity of reported compounds related to their tendency towards P-N bond cleavage.

Asunto(s)

Antibacterianos/síntesis química , Antibacterianos/farmacología , Química Farmacéutica/métodos , Pruebas de Sensibilidad Microbiana , Níquel/química , Biopelículas/efectos de los fármacos , Candida/efectos de los fármacos , Complejos de Coordinación/química , Diseño de Fármacos , Escherichia/efectos de los fármacos , Hidrólisis , Ligandos , Modelos Moleculares , Nitrógeno/química , Fósforo/química , Pseudomonas/efectos de los fármacos , Teoría Cuántica , Espectroscopía Infrarroja por Transformada de Fourier , Staphylococcus aureus/efectos de los fármacos , Staphylococcus haemolyticus/efectos de los fármacos , Difracción de Rayos X

RESUMEN

Linezolid resistance has increasingly been described in coagulase negative staphylococci (CoNS) in recent years. Here, we describe the molecular mechanism of linezolid resistance in Staphylococcus haemolyticus using whole genome sequencing. Three S. haemolyticus isolates (VB5326, VB19458, and VB840) carried G2576T mutation at the domain V of the 23S rRNA. In addition, VB5326 and VB19458 carried the cfr gene in the chromosome. The presence of cfr gene, in combination with G2576T mutation in 23S rRNA, resulted in a high linezolid Minimum inhibitory concentration (MIC) of > 256 µg/ml. Three mutations, including D471E, I527M, and S532N, in rpoB contributed to an increased rifampicin MIC of 32 µg/ml. Subsequent development of linezolid and rifampicin resistance in S. haemolyticus is worrisome and greatly limits clinical management.

Asunto(s)

Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple/genética , Linezolid/farmacología , Rifampin/farmacología , Staphylococcus haemolyticus/efectos de los fármacos , Staphylococcus haemolyticus/genética , Antibióticos Antituberculosos/farmacología , Genoma , Humanos , India , Análisis de Secuencia

RESUMEN

BACKGROUND: Coagulase negative Staphylococci (CoNS) are important. The common antibiotics used for the treatment of the infections caused by CoNS are penicillin, oxacillin, ciprofloxacin, clindamycin, erythromycin, gentamicin, and vancomycin. Linezolid is an oxazolidinone group of antibiotic with activity against Gram-positive bacteria. It is used for the treatment of serious infections caused by Gram-positive bacteria resistant to other antibiotics, including streptococci, vancomycin-resistant enterococci (VRE). AIMS AND OBJECTIVE: This study emphasizes on the judicious use of newer antibiotics to contain the spread of resistance. METHOD: We are discussing five cases of Linezolid resistant Staphylococcus Haemolyticus which were reported in our laboratory during one year from patients with device related infections and also review of literature is being presented for an update. RESULT: In our study, the isolates were resistant to other groups of antimicrobials but susceptible to glycopeptides. All the isolates were methicillin-resistant. CONCLUSION: Linezolid is approved as an alternative drug to be given for catheter-related bloodstream infections. In earlier studies, linezolid-resistant staphylococci have been reported increasingly all over the world. This study is to create awareness amongst clinicians that improper and excessive use of linezolid will make this antibiotic-resistant and thus will be of no help in future, so judicious and relevant use of antibiotics needs to be emphasized.

Asunto(s)

Farmacorresistencia Bacteriana/efectos de los fármacos , Equipos y Suministros/microbiología , Glicopéptidos/farmacología , Infecciones Estafilocócicas/microbiología , Staphylococcus haemolyticus/efectos de los fármacos , Adulto , Anciano , Femenino , Glicopéptidos/uso terapéutico , Humanos , Linezolid/farmacología , Masculino , Resistencia a la Meticilina/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus haemolyticus/aislamiento & purificación , Resultado del Tratamiento , Adulto Joven

RESUMEN

Grape seeds are considered one of the most important sources for phenolic and other compounds and is globally consumed for the biological value of its active ingredients. The increasing prevalence of Methicillin-resistant Staphylococcus aureus-related infections has become a very challenging health issue worldwide. This work aims at examining the antibacterial activity of alcoholic extract of black grape seeds (Vitis vinifera) against biofilm formation by Staphylococcus aureus and Staphylococcus haemolyticus. Staphylococcal bacterial isolates were first clinically confirmed using the VITEK-2compact system (ID and AST), and four isolates were selected depending on virulence and resistance to different types of antibiotics. The ability of S. aureus and S. haemolyticus isolates to form biofilm was examined using a standardized 96-well microtiter plate method. Furthermore, the effect of Moxifloxacin and Penicillin G with MIC, sub-MIC and sub-sub-MIC in preventing S. aureus and S. haemolyticus biofilm production, as well as that of the grape seed extract (180 mg/ml) were tested against biofilm formation. Our data indicate that all of the Staphylococcal bacterial isolates were able to produce biofilm which was prevented by the methanolic extracts of the crude seeds of Vitis vinifera rich in galloylated catechin esters of gallic acid. A significant (P < 0.001) synergistic effect between Penicillin G, Moxifloxacin with MIC, sub-MIC and sub-sub-MIC and that of the methanolic extract of Vitis vinifera (180 mg/ml) against bacterial biofilm formation was also detected. This report confirms the antibacterial activity of the methanolic extract of the black grape seeds.

Asunto(s)

Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Extracto de Semillas de Uva/farmacología , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus haemolyticus/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Fenoles/farmacología

RESUMEN

Empirical combination therapy with ß-lactams and glycopeptides is recommended for patients with presumed staphylococcal bloodstream infection (BSI). While coagulase-negative staphylococci (CNS) remain susceptible to vancomycin, such isolates have become less susceptible to teicoplanin. The aim of this retrospective study was to evaluate the clinical efficacy of teicoplanin in the treatment of BSI caused by methicillin-resistant CNS according to teicoplanin susceptibility. Inclusion criteria were patients with intravascular-catheter related BSIs caused by methicillin-resistant CNS (positive for two or more specimens); teicoplanin therapy; and at least one of the signs or symptoms caused by BSI. Antimicrobial resistance was defined as minimum inhibitory concentration (MIC) ≥8 µg/mL. The primary efficacy endpoint was clinical success evaluated 2 weeks after the completion of teicoplanin therapy [test of cure (TOC)]. Resistant rate of CNS was 0% for vancomycin and 22.9% for teicoplanin, and geometric mean MICs were 1.31 µg/mL and 3.41 µg/mL, respectively (p < 0.001). The catheter was removed in all patients except one, and high early clinical response at 72 h after starting therapy was obtained irrespective of teicoplanin susceptibility. The clinical success rate at TOC was 60% in patients with BSIs caused by teicoplanin-resistant strains, while 90% in patients with BSIs caused by susceptible strains (p = 0.052). In multivariate analyses, teicoplanin resistance was significant factor for decreased clinical success at TOC (adjusted odds ratio 0.138, 95% confidence interval 0.020-0.961, p = 0.045). Because of the poor clinical efficacy of teicoplanin against teicoplanin-resistant CNS, combination therapy comprising vancomycin and ß-lactam antibiotics should be considered in presumed staphylococci BSI.

Asunto(s)

Bacteriemia/tratamiento farmacológico , Resistencia a la Meticilina , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus/aislamiento & purificación , Teicoplanina/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/uso terapéutico , Bacteriemia/microbiología , Infecciones Relacionadas con Catéteres/tratamiento farmacológico , Infecciones Relacionadas con Catéteres/microbiología , Coagulasa/metabolismo , Femenino , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Estudios Retrospectivos , Infecciones Estafilocócicas/microbiología , Staphylococcus/efectos de los fármacos , Staphylococcus epidermidis/efectos de los fármacos , Staphylococcus epidermidis/aislamiento & purificación , Staphylococcus haemolyticus/efectos de los fármacos , Staphylococcus haemolyticus/aislamiento & purificación , Resultado del Tratamiento , Vancomicina/uso terapéutico

RESUMEN

This study compared changes in antimicrobial susceptibilities and molecular characteristics of coagulase-negative staphylococci (CNS) between the year 2000 and the year 2014-2015 to evaluate the policy of separating drug prescribing and dispensing in Korea. We obtained 68 CNS clinical isolates from two tertiary general hospitals before (the year 2000; n = 25) and after (the year 2014 - 2015; n = 43) implementation of the separation. Isolates were identified as Staphylococcus capitis, Staphylococcus epidermidis, Staphylococcus haemolyticus, Staphylococcus hominis, Staphylococcus saprophyticus, and Staphylococcus warneri. When minimal inhibitory concentrations of 14 antimicrobials were applied to isolates, resistance rates to gentamicin and oxacillin in 2000 were significantly higher than in 2014-2015 (p < 0.05). Fifty-seven isolates were methicillin-resistant CNS (MR-CNS), 42 of which were also multidrug resistant; overall, multidrug resistance decreased from 72% in the year 2000 to 55.8% in 2014-2015. Staphylococcal cassette chromosome mec (SCCmec) type III was the dominant type of MR-CNS in the year 2000, while SCCmec type IV was the dominant type in 2014-2015. Twenty-five sequence types (STs) were identified; ST2 appeared most frequently in both periods. After 15 years of implementation of this policy, multidrug resistance as well as methicillin and gentamicin resistance in CNS decreased, but not resistance to other antibiotics. Long-term surveillance at both genotypic and phenotypic levels of various species is necessary for further evaluation of this policy.

Asunto(s)

Antibacterianos/farmacología , Prescripciones de Medicamentos/estadística & datos numéricos , Farmacorresistencia Bacteriana Múltiple/genética , Infecciones Estafilocócicas/epidemiología , Staphylococcus epidermidis/genética , Staphylococcus haemolyticus/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Coagulasa/deficiencia , Coagulasa/genética , Expresión Génica , Gentamicinas/farmacología , Humanos , Legislación de Medicamentos , Pruebas de Sensibilidad Microbiana , Oxacilina/farmacología , Filogenia , República de Corea/epidemiología , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Staphylococcus , Staphylococcus capitis/clasificación , Staphylococcus capitis/efectos de los fármacos , Staphylococcus capitis/genética , Staphylococcus capitis/aislamiento & purificación , Staphylococcus epidermidis/clasificación , Staphylococcus epidermidis/efectos de los fármacos , Staphylococcus epidermidis/aislamiento & purificación , Staphylococcus haemolyticus/clasificación , Staphylococcus haemolyticus/efectos de los fármacos , Staphylococcus haemolyticus/aislamiento & purificación , Staphylococcus hominis/clasificación , Staphylococcus hominis/efectos de los fármacos , Staphylococcus hominis/genética , Staphylococcus hominis/aislamiento & purificación , Staphylococcus saprophyticus , Centros de Atención Terciaria

Asunto(s)

Farmacorresistencia Bacteriana/genética , ARN Ribosómico 23S/genética , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus haemolyticus/genética , Adulto , Antibacterianos/uso terapéutico , Femenino , Humanos , India , Linezolid/administración & dosificación , Linezolid/efectos adversos , Masculino , Staphylococcus aureus Resistente a Meticilina/genética , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Mutación/genética , Dominios Proteicos/genética , Infecciones Estafilocócicas/genética , Infecciones Estafilocócicas/microbiología , Staphylococcus haemolyticus/efectos de los fármacos , Staphylococcus haemolyticus/patogenicidad , Centros de Atención Terciaria

RESUMEN

Staphylococcus haemolyticus is the most common organism among clinical isolatesof methicillin-resistant staphylococci. Aim: This study evaluated the ability to produce biofilm with the presence of the antibiotics (1/4 minimum inhibitory concentrations) of S. haemolyticus strains isolated from blood culture. Methods: Clonal distribution was assessed in pulsed-field gel electrophoresis. PCR assays were performed to detect mecA, icaA, aap, atlE, atl, fbp genes. S. haemolyticus strains grown in the presence of the antibiotics were investigated for biofilm formation on glass, polystyrene and catheter surfaces. Results: Biofilm formation was independent of the presence of the icaA and mecA genes, pulsed-field gel electrophoresis type. Vancomycin, oxacillin, moxifloxacin, rifampicin, teicoplanin, tigecycline and linezolid did not inhibit biofilm formation on abiotic surfaces. Conclusion: This study demonstrated that the biofilm formation process is complex and may not be related to ica gene carriage. Furthermore, in this study the biofilm formation was increased in the presence of antimicrobial agents.

Asunto(s)

Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Staphylococcus haemolyticus/efectos de los fármacos , Staphylococcus haemolyticus/crecimiento & desarrollo , Bacteriemia/microbiología , Electroforesis en Gel de Campo Pulsado , Genes Bacterianos , Genotipo , Humanos , Pruebas de Sensibilidad Microbiana , Tipificación Molecular , Reacción en Cadena de la Polimerasa , Infecciones Estafilocócicas/microbiología , Staphylococcus haemolyticus/clasificación , Staphylococcus haemolyticus/aislamiento & purificación

RESUMEN

Antibiotic resistance crisis occasioned by sporadic appearance of multi-drug resistance (MDR) in human pathogens to clinically applied antimicrobials is a serious threat to global health. In this study, we investigated the drug resistant phenotype of Gram-positive cocci isolates from environment. Staphylococcus capitis and Staphylococcus haemolyticus colonies were isolated on mannitol-salt agar plates supplemented with tetracycline. Antibiotic susceptibility profile of the isolates via minimum inhibitory concentration (MIC) determination was examined. Isolates showed decreased sensitivity to clinically applied antimicrobial agents: tetracycline, kanamycin, erythromycin, norfloxacin, teicoplanin, and ampicillin. Genomic analysis demonstrated the presence of multiple antibiotic resistant genes in these bacteria, suggesting the origin of the multiple antimicrobials resistant phenotype. Tetracycline resistance of these isolates was transduced to Staphylococcus aureus-RN4220 strain. These findings indicate the presence of multiple antimicrobials resistant S. capitis and S. haemolyticus strain in a non-hospital setting. Moreover, the presence of plethora of genes responsible for MDR suggest that these strains could present potential threat to human health by serving as reservoir for lateral transference of antimicrobial resistance conferring foreign genetic elements to other clinically relevant pathogens.

Asunto(s)

Farmacorresistencia Bacteriana Múltiple , Staphylococcus capitis/aislamiento & purificación , Staphylococcus haemolyticus/aislamiento & purificación , Secuenciación Completa del Genoma/métodos , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Composición de Base , Coagulasa/metabolismo , Tamaño del Genoma , Pruebas de Sensibilidad Microbiana , Staphylococcus capitis/efectos de los fármacos , Staphylococcus capitis/genética , Staphylococcus haemolyticus/efectos de los fármacos , Staphylococcus haemolyticus/genética

RESUMEN

A 61 year male, admitted in Combined Military Hospital Rawlpindi on 12th March 2017, operated for diverticulitis became colonized with Staphylococcus haemolyticus. Patient suffered repeated septic episodes caused by the same organism during his stay in hospital. The strain was identified as methicillin resistant Staphylococcus haemolyticus (MRSH) also resistant to Linezolid by analytical profile index for Staphylococcus (API Staph) and VITEK 2 Gram positive cocci panel. The isolate was cultured from blood cultures, Central Venous Catheter (CVC) tip and skin swabs. Patient was successfully treated with injectable vancomycin and skin decolonization was acheived with chlorhexidine bath after which no episode of MRSH infection occurred. Patient had an uneventful recovery and was discharged on 21st June. His follow up visit showed clinical improvement.

Asunto(s)

Infecciones Relacionadas con Catéteres , Clorhexidina/administración & dosificación , Infección Hospitalaria , Resistencia a la Meticilina , Sepsis , Infecciones Estafilocócicas , Staphylococcus haemolyticus , Vancomicina/administración & dosificación , Antibacterianos/administración & dosificación , Baños/métodos , Infecciones Relacionadas con Catéteres/microbiología , Infecciones Relacionadas con Catéteres/fisiopatología , Infecciones Relacionadas con Catéteres/terapia , Infección Hospitalaria/microbiología , Infección Hospitalaria/fisiopatología , Infección Hospitalaria/terapia , Humanos , Inyecciones , Linezolid/farmacología , Masculino , Persona de Mediana Edad , Prevención Secundaria , Sepsis/microbiología , Sepsis/fisiopatología , Sepsis/terapia , Infecciones Estafilocócicas/diagnóstico , Infecciones Estafilocócicas/fisiopatología , Infecciones Estafilocócicas/terapia , Staphylococcus haemolyticus/efectos de los fármacos , Staphylococcus haemolyticus/aislamiento & purificación

RESUMEN

In traditional medicine, Morinda citrifolia (Noni) is used to treat various ailments, including skin and respiratory-tract infections. In this work, a bio-directed study (seed extracts) with five bacteria was carried out against four clinical isolates of Methicillin-Resistant Staphylococcus (MRS) and Staphylococcus aureus ATCC 29213 strain to find molecules capable of inhibiting them. Three organic extracts were obtained by maceration of the noni seeds with ascending polarity solvents (n-hexane, dichloromethane and methanol) that were evaluated as antibacterial in the model of bioautography and broth microdilution techniques. The results showed that the methanolic extract was the most active against all bacteria (MIC = 16 mg/mL). The chromatographic fractionation performed on this extract allowed obtaining six fractions (EMF1-EMF6), of which F1, F2 and F5 exhibited activity against some of the bacteria. EMF1 fraction reached an MIC of 25 µg/mL against S. haemolyticus twice as much as the positive control, in which the chemical content is mainly composed of a mixture of γ-butyrolactones (1-2) and esterified fatty acids (3-9); chemical characterization of the nine compounds was carried out based on gas chromatography coupled to masses. EMF2 fraction, presented an MIC of 200 µg/mL against S. aureus 0198 and S. haemolyticus 562B, where a coumarin known as scopoletin (10) was isolated and active against S. aureus 0198 (MIC = 100 µg/mL). EMF5 fraction demonstrated an MIC of 200 µg/mL against S. aureus 0198, S. haemolyticus 562B and S. epidermidis 1042, in which a neolignan known as americanin A (11) was identified, showing activity against S. haemolyticus 562B and S. epidermidis 1042 (MIC = 100 µg/mL). The chemical characterization of isolated compounds 10 and 11 was performed by the analysis of 1H and 13C NMR. Therefore, the methanolic extract, identified and isolated compounds showed important antibacterial activity against the MRS, validating its use in traditional medicine.

Asunto(s)

Antibacterianos/farmacología , Morinda/química , Extractos Vegetales/farmacología , Semillas/química , Staphylococcus/efectos de los fármacos , Antibacterianos/química , Butirofenonas/farmacología , Dioxinas/farmacología , Ácidos Grasos/farmacología , Cromatografía de Gases y Espectrometría de Masas , Espectroscopía de Resonancia Magnética , Medicina Tradicional , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/química , Escopoletina/farmacología , Staphylococcus aureus/efectos de los fármacos , Staphylococcus epidermidis/efectos de los fármacos , Staphylococcus haemolyticus/efectos de los fármacos

RESUMEN

Staphylococcus lugdunensis and Staphylococcus haemolyticus are unique among CoNS in that the former often causes aggressive disease, while the latter consistently exhibits high rates of multidrug resistance. We evaluated the in vitro susceptibility of contemporary (2012-2013) isolates from both pathogens to tedizolid and comparators, using standard methodology. Results were interpreted using CLSI and EUCAST breakpoints. Overall, 106 S. lugdunensis and 103 S. haemolyticus isolates were collected from 51 medical centers in the United States and 30 centers in 18 European countries. Tedizolid showed good activity against S. lugdunensis (MIC50/MIC90: 0.12/0.12 mg/L) and S. haemolyticus (MIC50/MIC90: 0.12/0.12 mg/L), inhibiting all isolates at MIC ≤0.25 mg/L. Based on the EUCAST breakpoint for staphylococci and when substituting the CLSI breakpoint for Staphylococcus aureus, all isolates were tedizolid susceptible. All isolates were also susceptible to linezolid, but the in vitro potency of tedizolid was 4-fold greater than that of linezolid against both S. lugdunensis and S. haemolyticus, based on MIC90 values. S. lugdunensis exhibited ≥99% susceptibility to vancomycin, teicoplanin, gentamicin, levofloxacin, and trimethoprim-sulfamethoxazole; 7% of isolates were resistant to tetracycline, 11% to clindamycin, and 2% were methicillin-resistant. S. haemolyticus exhibited high rates of resistance to commonly used anti-staphylococcal agents: 71% of isolates were resistant to methicillin, 36%-37% to clindamycin, and 30%-50% to gentamicin. These in vitro findings suggest that tedizolid could be an alternative treatment option for infections due to these medically important CoNS pathogens. Additional clinical evaluation and continued surveillance of tedizolid in vitro activity against S. lugdunensis and S. haemolyticus are warranted.

Asunto(s)

Antibacterianos/farmacología , Oxazolidinonas/farmacología , Staphylococcus haemolyticus/efectos de los fármacos , Staphylococcus lugdunensis/efectos de los fármacos , Tetrazoles/farmacología , Coagulasa/deficiencia , Farmacorresistencia Bacteriana/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana/normas , Viabilidad Microbiana/efectos de los fármacos , Infecciones Estafilocócicas/microbiología , Staphylococcus haemolyticus/aislamiento & purificación , Staphylococcus lugdunensis/aislamiento & purificación