Ecotoxicity of five veterinary antibiotics on indicator organisms and water and soil communities.

This study explores the environmental effects of five common veterinary antibiotics widely detected in the environment, (chlortetracycline,CTC; oxytetracycline,OTC; florfenicol,FF; neomycin, NMC; and sulfadiazine, SDZ) on four bioindicators: Daphnia magna, Vibrio fischeri, Eisenia fetida, and Allium cepa, representing aquatic and soil environments. Additionally, microbial communities characterized through 16 S rRNA gene sequencing from a river and natural soil were exposed to the antibiotics to assess changes in population growth and metabolic profiles using Biolog EcoPlates™. Tetracyclines are harmful to Vibrio fisheri (LC50 ranges of 15-25 µg/mL), and the other three antibiotics seem to only affect D. magna, especially, SDZ. None of the antibiotics produced mortality in E. fetida at concentrations below 1000 mg/kg. NMC and CTC had the highest phytotoxicities in A. cepa (LC50 = 97-174 µg/mL, respectively). Antibiotics significantly reduced bacterial metabolism at 0.1-10 µg/mL. From the highest to the lowest toxicity on aquatic communities: OTC > FF > SDZ ≈ CTC > NMC and on edaphic communities: CTC ≈ OTC > FF > SDZ > NMC. In river communities, OTC and FF caused substantial decreases in bacterial metabolism at low concentrations (0.1 µg/mL), impacting carbohydrates, amino acids (OTC), and polymers (FF). At 10 µg/mL and above, OTC, CTC, and FF significantly decreased metabolizing all tested metabolites. In soil communities, a more pronounced decrease in metabolizing ability, detectable at 0.1 µg/mL, particularly affected amines/amides and carboxylic and ketonic acids (p < 0.05). These new ecotoxicity findings underscore that the concentrations of these antibiotics in the environment can significantly impact both aquatic and terrestrial ecosystems.

Hydroquinone Ecotoxicity: Unveiling Risks in Soil and River Ecosystems with Insights into Microbial Resilience.

Despite widespread industrial use, the environmental safety of hydroquinone (HQ), a benzene compound from plants used in processes like cosmetics, remains uncertain. This study evaluated the ecotoxicological impact of HQ on soil and river environments, utilizing non-target indicator organisms from diverse trophic levels: Daphnia magna, Aliivibrio fischeri, Allium cepa, and Eisenia fetida. For a more environmentally realistic assessment, microbial communities from a river and untreated soil underwent 16S rRNA gene sequencing, with growth and changes in community-level physiological profiling assessed using Biolog EcoPlate™ assays. The water indicator D. magna exhibited the highest sensitivity to HQ (EC50 = 0.142 µg/mL), followed by A. fischeri (EC50 = 1.446 µg/mL), and A. cepa (LC50 = 7.631 µg/mL), while E. fetida showed the highest resistance (EC50 = 234 mg/Kg). Remarkably, microbial communities mitigated HQ impact in both aquatic and terrestrial environments. River microorganisms displayed minimal inhibition, except for a significant reduction in polymer metabolism at the highest concentration (100 µg/mL). Soil communities demonstrated resilience up to 100 µg/mL, beyond which there was a significant decrease in population growth and the capacity to metabolize carbohydrates and polymers. Despite microbial mitigation, HQ remains highly toxic to various trophic levels, emphasizing the necessity for environmental regulations.

Synergistic Activity of Thymol with Commercial Antibiotics against Critical and High WHO Priority Pathogenic Bacteria.

The use of synergistic combinations between natural compounds and commercial antibiotics may be a good strategy to fight against microbial resistance, with fewer side effects on human, animal and environmental, health. The antimicrobial capacity of four compounds of plant origin (thymol and gallic, salicylic and gentisic acids) was analysed against 14 pathogenic bacteria. Thymol showed the best antimicrobial activity, with MICs ranging from 125 µg/mL (for Acinetobacter baumannii, Pasteurella aerogenes, and Salmonella typhimurium) to 250 µg/mL (for Bacillus subtilis, Klebsiella aerogenes, Klebsiella pneumoniae, Serratia marcescens, Staphylococcus aureus, and Streptococcus agalactiae). Combinations of thymol with eight widely used antibiotics were studied to identify combinations with synergistic effects. Thymol showed synergistic activity with chloramphenicol against A. baumannii (critical priority by the WHO), with streptomycin and gentamicin against Staphylococcus aureus (high priority by the WHO), and with streptomycin against Streptococcus agalactiae, decreasing the MICs of these antibiotics by 75% to 87.5%. The kinetics of these synergies indicated that thymol alone at the synergy concentration had almost no effect on the maximum achievable population density and very little effect on the growth rate. However, in combination with antibiotics at the same concentration, it completely inhibited growth, confirming its role in facilitating the action of the antibiotic. The time-kill curves indicated that all the combinations with synergistic effects were mainly bactericidal.

Diversity of metal and antibiotic resistance genes in Enterococcus spp. from the last century reflects multiple pollution and genetic exchange among phyla from overlapping ecosystems.

Arsenic (As), mercury (Hg), and copper (Cu) are among the major historical and contemporary metal pollutants linked to global anthropogenic activities. Enterococcus have been considered indicators of fecal pollution and antibiotic resistance for years, but its largely underexplored metallome precludes understanding their role as metal pollution bioindicators as well. Our goal was to determine the occurrence, diversity, and phenotypes associated with known acquired genes/operons conferring tolerance to As, Hg or Cu among Enterococcus and to identify their genetic context (381 field isolates from diverse epidemiological and genetic backgrounds; 3547 enterococcal genomes available in databases representing a time span during 1900-2019). Genes conferring tolerance to As (arsA), Hg (merA) or Cu (tcrB) were used as biomarkers of widespread metal tolerance operons. Different variants of metal tolerance (MeT) genes (13 arsA, 6 merA, 1 tcrB) were more commonly recovered from the food-chain (arsA, tcrB) or humans (merA), and were shared with 49 other bacterial taxa. Comparative genomics analysis revealed that MeT genes occurred in heterogeneous operons, at least since the 1900s, with an increasing accretion of antibiotic resistance genes since the 1960's, reflecting diverse antimicrobial pollution. Multiple MeT genes were co-located on the chromosome or conjugative plasmids flanked by elements with high potential for recombination, often along with antibiotic resistance genes. Phenotypic analysis of some isolates carrying MeT genes revealed up to 128× fold increase in the minimum inhibitory concentrations to metals. The main distribution of functional MeT genes among Enterococcus faecium and Enterococcus faecalis from different sources, time spans, and clonal lineages, and their ability to acquire diverse genes from multiple taxa bacterial communities places these species as good candidates to be used as model organisms in future projects aiming at the identification and quantification of bioindicators of metal polluted environments by anthropogenic activities.

Optical Interrogation of Single Levitated Droplets in a Linear Quadrupole Trap by Cavity Ring-Down Spectroscopy.

Optical trapping is a well-established technique to manipulate and levitate micro- and nanoscale particles and droplets. However, optical traps for single aerosol studies are most often limited to trapping spherical nonabsorbing droplets, and a universal optical trap for the stable confinement of particles regardless of their absorption strength and morphology is not established. Instead, new opportunities arise from levitating droplets using electrodynamic traps. Here, using a combined electrodynamic linear quadrupole trap and a cavity ring-down spectrometer, we demonstrate that it is possible to trap single droplets and simultaneously measure their extinction cross sections and elastic scattering phase functions over extended periods of time. To test the novel setup, we evaluated the evaporation of 1,2,6-hexanetriol under low-humidity conditions, and the evolution of aqueous (NH4)2SO4 and NaCl droplets experiencing changing environmental conditions. Our studies extended beyond spherical droplets and we measured particle extinction cross sections after the efflorescence (crystallization) of the inorganic salt particles. Comparison of measured cross sections for crystallized particles with light scattering model predictions (using Mie theory or the T-matrix/extended boundary-condition method (EBCM) implementations for random orientation, with either the spheroid or superellipsoid parameterizations) enables information on particle shape to be inferred. Specifically, we find that cross sections for dry (NH4)2SO4 particles are accounted for by Mie theory and, thus, particle shape is represented well by a sphere. Conversely, the cross sections for dry NaCl particles are only reconciled with light scattering models pertaining to nonspherical shapes. These results will have implications for accurate remote sensing retrievals of dry salt optical properties and for parameterizations implemented in radiative forcing calculations with changing humidity. Moreover, our new platform for precise and accurate measurement of optical properties of micron-scale and sub-micron particles has potential applications in a range of areas of atmospheric science, such as precise light scattering measurements for ice crystals and mineral dust. It represents a promising step toward accurate characterizations of optical properties for nonspherical and light-absorbing aerosols.

Effectiveness and safety of olive oil preparation for topical use in pressure ulcer prevention: Multicentre, controlled, randomised, and double-blinded clinical trial.

This non-inferiority, multicentre, randomised, controlled, and double-blinded clinical trial compared the therapeutic effectiveness of the topical application of an olive oil solution with that of a hyperoxygenated fatty acid compound for the prevention of pressure ulcers in at-risk nursing home residents. The study population comprised 571 residents of 23 nursing homes with pressure ulcer risk, randomly assigned to a hyperoxygenated fatty acid group (n = 288) or olive oil solution group (n = 283). Both solutions were applied on at-risk skin areas every 12 hours for 30 days or until pressure ulcer onset. The main outcome variable was the pressure ulcer incidence. The absolute risk difference was estimated (with 95% CI) using Kaplan-Meier survival and Cox regression curves. The groups did not significantly differ in any study variable at baseline. The pressure ulcer incidence was 4.18% in the olive oil group vs 6.57% in the control group, with an incidence difference of -2.39% (95% CI = -6.40 to 1.56%), which is within the pre-established non-inferiority margin of ±7%, thus supporting the study hypothesis. We present the first evidence of the effectiveness and safety of the topical application of olive oil to prevent pressure ulcers in the institutionalised elderly.

In-depth resistome analysis by targeted metagenomics.

BACKGROUND: Antimicrobial resistance is a major global health challenge. Metagenomics allows analyzing the presence and dynamics of "resistomes" (the ensemble of genes encoding antimicrobial resistance in a given microbiome) in disparate microbial ecosystems. However, the low sensitivity and specificity of available metagenomic methods preclude the detection of minority populations (often present below their detection threshold) and/or the identification of allelic variants that differ in the resulting phenotype. Here, we describe a novel strategy that combines targeted metagenomics using last generation in-solution capture platforms, with novel bioinformatics tools to establish a standardized framework that allows both quantitative and qualitative analyses of resistomes. METHODS: We developed ResCap, a targeted sequence capture platform based on SeqCapEZ (NimbleGene) technology, which includes probes for 8667 canonical resistance genes (7963 antibiotic resistance genes and 704 genes conferring resistance to metals or biocides), and 2517 relaxase genes (plasmid markers) and 78,600 genes homologous to the previous identified targets (47,806 for antibiotics and 30,794 for biocides or metals). Its performance was compared with metagenomic shotgun sequencing (MSS) for 17 fecal samples (9 humans, 8 swine). ResCap significantly improves MSS to detect "gene abundance" (from 2.0 to 83.2%) and "gene diversity" (26 versus 14.9 genes unequivocally detected per sample per million of reads; the number of reads unequivocally mapped increasing up to 300-fold by using ResCap), which were calculated using novel bioinformatic tools. ResCap also facilitated the analysis of novel genes potentially involved in the resistance to antibiotics, metals, biocides, or any combination thereof. CONCLUSIONS: ResCap, the first targeted sequence capture, specifically developed to analyze resistomes, greatly enhances the sensitivity and specificity of available metagenomic methods and offers the possibility to analyze genes related to the selection and transfer of antimicrobial resistance (biocides, heavy metals, plasmids). The model opens the possibility to study other complex microbial systems in which minority populations play a relevant role.

Does Transcranial Direct Current Stimulation Combined with Peripheral Electrical Stimulation Have an Additive Effect in the Control of Hip Joint Osteonecrosis Pain Associated with Sickle Cell Disease? A Protocol for a One-Session Double Blind, Block-Randomized Clinical Trial.

Chronic pain in Sickle Cell Disease (SCD) is probably related to maladaptive plasticity of brain areas involved in nociceptive processing. Transcranial Direct Current Stimulation (tDCS) and Peripheral Electrical Stimulation (PES) can modulate cortical excitability and help to control chronic pain. Studies have shown that combined use of tDCS and PES has additive effects. However, to date, no study investigated additive effects of these neuromodulatory techniques on chronic pain in patients with SCD. This protocol describes a study aiming to assess whether combined use of tDCS and PES more effectively alleviate pain in patients with SCD compared to single use of each technique. The study consists of a one-session double blind, block-randomized clinical trial (NCT02813629) in which 128 participants with SCD and femoral osteonecrosis will be enrolled. Stepwise procedures will occur on two independent days. On day 1, participants will be screened for eligibility criteria. On day 2, data collection will occur in four stages: sample characterization, baseline assessment, intervention, and post-intervention assessment. These procedures will last ~5 h. Participants will be divided into two groups according to homozygous for S allele (HbSS) (n = 64) and heterozygous for S and C alleles (HbSC) (n = 64) genotypes. Participants in each group will be randomly assigned, equally, to one of the following interventions: (1) active tDCS + active PES; (2) active tDCS + sham PES; (3) sham tDCS + active PES; and (4) sham tDCS + sham PES. Active tDCS intervention will consist of 20 min 2 mA anodic stimulation over the primary motor cortex contralateral to the most painful hip. Active PES intervention will consist of 30 min sensory electrical stimulation at 100 Hz over the most painful hip. The main study outcome will be pain intensity, measured by a Visual Analogue Scale. In addition, electroencephalographic power density, cortical maps of the gluteus maximus muscle elicited by Transcranial Magnetic Stimulation (TMS), serum levels of Brain-derived Neurotrophic Factor (BDNF), and Tumor Necrosis Factor (TNF) will be assessed as secondary outcomes. Data will be analyzed using ANOVA of repeated measures, controlling for confounding variables.

Multilevel population genetic analysis of vanA and vanB Enterococcus faecium causing nosocomial outbreaks in 27 countries (1986-2012).

OBJECTIVES: Vancomycin-resistant Enterococcus faecium (VREfm) have been increasingly reported since the 1980s. Despite the high number of published studies about VRE epidemiology, the dynamics and evolvability of these microorganisms are still not fully understood. A multilevel population genetic analysis of VREfm outbreak strains since 1986, representing the first comprehensive characterization of plasmid content in E. faecium, was performed to provide a detailed view of potential transmissible units. METHODS: From a comprehensive MeSH search, we identified VREfm strains causing hospital outbreaks (1986-2012). In total, 53 VanA and 18 VanB isolates (27 countries, 5 continents) were analysed and 82 vancomycin-susceptible E. faecium (VSEfm) were included for comparison. Clonal relatedness was established by PFGE and MLST (goeBURST/Bayesian Analysis of Population Structure, BAPS). Characterization of van transposons (PCR mapping, RFLP, sequencing), plasmids (transfer, ClaI-RFLP, PCR typing of relaxases, replication-initiation proteins and toxin-antitoxin systems, hybridization, sequencing), bacteriocins and virulence determinants (PCR, hybridization, sequencing) was performed. RESULTS: VREfm were mainly associated with major human lineages ST17, ST18 and ST78. VREfm and VSEfm harboured plasmids of different families [RCR, small theta plasmids, RepA_N (pRUM/pLG1) and Inc18] able to yield mosaic elements. Tn1546-vanA was mainly located on pRUM/Axe-Txe (USA) and Inc18-pIP186 (Europe) plasmids. The VanB2 type (Tn5382/Tn1549) was predominant among VanB strains (chromosome and plasmids). CONCLUSIONS: Both strains and plasmids contributed to the spread and persistence of vancomycin resistance among E. faecium. Horizontal gene transfer events among genetic elements from different clonal lineages (same or different species) result in chimeras with different stability and host range, complicating the surveillance of epidemic plasmids.

Role of EfrAB efflux pump in biocide tolerance and antibiotic resistance of Enterococcus faecalis and Enterococcus faecium isolated from traditional fermented foods and the effect of EDTA as EfrAB inhibitor.

Enterococcus faecalis and Enterococcus faecium isolated from various traditional fermented foods of both animal and vegetable origins have shown multidrug resistance to several antibiotics and tolerance to biocides. Reduced susceptibility was intra and inter-species dependent and was due to specific and unspecific mechanisms such as efflux pumps. EfrAB, a heterodimeric ABC transporter efflux pump, was detected in 100% of multidrug resistant (MDR) E. faecalis strains and only in 12% of MDR E. faecium strains. EfrAB expression was induced by half of minimum inhibitory concentration (MIC) of gentamicin, streptomycin and chloramphenicol. However, expression of efrA and efrB genes was highly dependent on the strain tested and on the antimicrobial used. Our results indicated that 3 mM EDTA highly reduced the MICs of almost all drugs tested. Nevertheless, the higher reductions (>8 folds) were obtained with gentamicin, streptomycin, chlorhexidine and triclosan. Reductions of MICs were correlated with down-regulation of EfrAB expression (10-140 folds) in all three MDR enterococci strains. This is the first report describing the role of EfrAB in the efflux of antibiotics and biocides which reflect also the importance of EfrAB in multidrug resistance in enterococci. EDTA used at low concentration as food preservative could be one of the best choices to prevent spread of multidrug resistant enterococci throughout food chain by decreasing EfrAB expression. EfrAB could be an attractive target not only in enterococci present in food matrix but also those causing infections as well by using EDTA as therapeutic agent in combination with low doses of antibiotics.

Eficacia en la prevención de úlceras por presión del aceite de oliva virgen extra frente a los ácidos grasos hiperoxigenados: resultados intermedios de un estudio de no inferioridad / Efficacy for preventing pressure ulcers of the virgin extra olive oil versus hyper-oxygenated fatty acids: intermediate results from a non-inferiority trial

Objetivos: a) Evaluar la eficacia de la aplicación tópica de aceite de oliva virgen extra en la prevención de úlceras por presión (UPP) en pacientes ancianos, en comparación con los ácidos grasos hiperoxigenados (AGHO), medida por la incidencia de UPP. b) Determinar la seguridad terapéutica (efectos adversos) de la aplicación tópica de aceite de oliva virgen extra. La hipótesis por contrastar es que la incidencia de UPP en el grupo tratado con el preparado de aceite de oliva no es superior a la incidencia de UPP en el grupo tratado con AGHO, estableciendo un margen de no inferioridad del 7%. Métodos: ensayo clínico de no inferioridad, multicéntrico, aleatorizado y controlado, con doble enmascaramiento. Se ha incluido a residentes de residencias de mayores en la provincia de Córdoba (España) con riesgo moderado o alto de UPP entre enero de 2011 y abril de 2013. Se excluyeron residentes que ya tenían alguna UPP al inicio, con enfermedad vascular o en situación de gravedad extrema. El tamaño de muestra estimado es de 560 personas, con un muestreo sistemático consecutivo en cada una de las residencias. La intervención testada fue la aplicación cada 12 horas, en zonas de riesgo, de un preparado de aceite oliva virgen extra (Oleicopiel) (grupo experimental) frente a la aplicación de AGHO (Mepentol) (grupo control). Variable principal: incidencia de UPP en cada grupo. Análisis de la diferencia de incidencias entre los dos grupos y tiempo hasta la aparición (análisis de supervivencia). Resultados: datos intermedios sobre una muestra de 247 residentes de 12 residencias. Ambos grupos son equivalentes al inicio. La incidencia de UPP en el grupo del aceite de oliva fue del 7,1% (8 de 112 residentes) y del 6,8% (8 de 117 residentes) en el grupo de AGHO, con una diferencia de incidencias del 0,31% (intervalo de confianza [IC] al 90% = -6,19% a +5,47%) que está dentro del margen de no inferioridad establecido de ±7% y apoya la hipótesis inicial. No se observó ningún efecto adverso en ninguno de los grupos. Conclusiones: se aportan las primeras evidencias sobre la eficacia y seguridad de la aplicación tópica del aceite de oliva virgen extra para prevenir la aparición de UPP en pacientes de residencias de mayores. De acuerdo con estas evidencias es posible afirmar que el producto de aceite de oliva virgen extra es, al menos, igual de eficaz que los AGHO y que, por tanto, es otra opción terapéutica para prevenir las UPP a disposición de los profesionales y los usuarios (AU)

Aims: a) To evaluate the efficacy of topical application of extra virgin olive oil in the prevention of pressure ulcers (PU) in elderly patients compared with hyper-oxygenated fatty acids (HFA), as measured by the incidence of PU. b) To establish the therapeutic safety (adverse effects) of the topical application of extra virgin olive oil. The hypothesis to be tested is that the incidence rate in the group treated with the olive oil shall not exceed the incidence rate in the group treated with HFA, establishing a non-inferiority margin of 7%. Methods: Multicentre, randomized, controlled, double blind, non-inferiority clinical trial. People living in nursing homes in the province of Córdoba (Spain) with moderate or high risk of pressure ulcers have been included. From January 2011 until April 2013. We excluded patients who already had some PU, with vascular disease or in extreme gravity condition. The sample size was estimated in 560 people. Sampling was systematic, enrolling eligible people consecutively in each of the residences. The intervention tested was the application every 12 hours in risk areas, of extra virgin olive oil (Oleicopiel) (experimental group) versus applying hyper-oxygenated fatty acids (Mepentol) (control group). Primary endpoint: incidence of PU in each group. Data analysis: difference in the incidence rates and time to onset (survival analysis). Results: Intermediate data on a sample of 247 patients from 12 nursing homes are reported. Both groups were equivalent at baseline. The PU incidence rate in the olive oil group was 7.1% (8/112 patients) and 6.8% (8/117 patients) in HFA group, with a difference in the incidence rate of 0.31% (90% CI = -6.19% to +5.47%), which is within the non-inferiority margin of ±7% and supports the initial hypothesis. No adverse effect was observed in either group. Conclusions: This paper provides the first evidence on the efficacy and safety of the topical application of extra virgin olive oil to prevent PU in patients at nursing homes. Based on this evidence we can conclude that the product of extra virgin olive oil tested is at least as effective as the HFA, and thus, is another therapeutic option to prevent pressure ulcers available for clinicians and users (AU)

Biocide and copper tolerance in enterococci from different sources.

Antimicrobial resistance in enterococci is a matter of concern. A collection of 272 strains (including 107 Enterococcus faecalis and 165 Enterococcus faecium strains) isolated from meat and dairy products, seafood, vegetable foods, wildflowers, animal feces (ewe, goat, horse, mule), and hospitals were tested for sensitivity to biocides of different classes (quaternary ammonium compounds, a bisphenol, and a biguanide) and copper sulfate. Most isolates were inhibited at 25 mg of benzalkonium chloride or cetrimide per liter or at 2.5 mg of hexadecylpyridinium chloride per liter. Few isolates had MICs higher than 25 mg/liter for benzalkonium chloride (2.2%), cetrimide (0.74%), or hexadecylpyridinium chloride (0.37%), although they were all inhibited at 250 mg/liter. The population response to triclosan was very homogeneous, and most isolates (98.16%) were inhibited at 250 mg of triclosan per liter. Chlorhexidine showed the greatest variability, with MICs in a range from 2.5 to 2,500 mg/liter. Remarkably, 74.57% of isolates from clinical samples required 2,500 mg of chlorhexidine per liter for inhibition, compared to much-lower concentrations required for most isolates from other sources. Enterococci were inhibited by copper sulfate in a concentration range from 4 to 16 mM, with no bimodal distribution. However, most isolates required 12 mM (41.91%) or 16 mM (47.43%) for inhibition. The highest percentages of isolates requiring 16 mM CuSO4 were from vegetable foods, seafood, and wildflowers. The results from the present study suggest intermediate levels of copper tolerance and a low incidence of biocide tolerance in the enterococci investigated, except for chlorhexidine in clinical isolates.

Phenotypic and molecular antibiotic resistance profile of Enterococcus faecalis and Enterococcus faecium isolated from different traditional fermented foods.

A collection of 55 enterococci (41 Enterococcus faecium and 14 E. faecalis strains) isolated from various traditional fermented foodstuffs of both animal and vegetable origins, and water was evaluated for resistance against 15 antibiotics. Lower incidence of resistance was observed with gentamicin, ampicillin, penicillin and teicoplanin. However, a high incidence of antibiotic resistance was detected for rifampicin (12 out of 14 of isolates), ciprofloxacin (9/14), and quinupristin/dalfopristin (8/14) in E. faecalis strains. Enterococcus faecium isolates were resistant to rifampicin (25/41), ciprofloxacin (23/41), erythromycin (18/41), levofloxacin (16/41), and nitrofurantoin (15/41). One Enterococcus faecalis and two E. faecium strains were resistant to vancomycin (MIC>16 µg/mL). Among 55 isolates, 27 (19 E. faecium and eight E. faecalis) were resistant to at least three antibiotics. High level of multidrug resistance to clinically important antibiotics was detected in E. faecalis strains (57% of E. faecalis versus 46% of E. faecium), which showed resistance to six to seven antibiotics, especially those isolated from foods of animal origin. So, it is necessary to re-evaluate the use of therapeutic antibiotics in stock farms at both regional and international levels due to the high number of multiple resistant (MR) bacteria. Fifty-six MR E. faecalis and E. faecium strains selected from this and previous studies (Valenzuela et al., 2008, 2010) were screened by polymerase chain reaction for antibiotic resistance genes, revealing the presence of tet(L), tet(M), ermB, cat, efrA, efrB, mphA, or msrA/B genes. The ABC Multidrug Efflux Pump EfrAB was detected in 96% of E. faecalis strains and also in 13% of E. faecium strains; this is the first report describing EfrAB in this enterococcal species. The efflux pump-associated msrA/B gene was detected in 66.66% of E. faecium strains, but not in E. faecalis strains.

Characterization of Enterococcus faecalis and Enterococcus faecium from wild flowers.

Wild flowers in the South of Spain were screened for Enterococcus faecalis and Enterococcus faecium. Enterococci were frequently associated with prickypear and fieldpoppy flowers. Forty-six isolates, from 8 different flower species, were identified as E. faecalis (28 isolates) or E. faecium (18 isolates) and clustered in well-defined groups by ERIC-PCR fingerprinting. A high incidence of antibiotic resistance was detected among the E. faecalis isolates, especially to quinupristin/dalfopristin (75%), rifampicin (68%) and ciprofloxacin (57%), and to a lesser extent to levofloxacin (35.7%), erythromycin (28.5%), tetracycline (3.5%), chloramphenicol (3.5%) and streptomycin (3.5%). Similar results were observed for E. faecium isolates, except for a higher incidence of resistance to tetracycline (17%) and lower to erythromycin (11%) or quinupristin/dalfopristin (22%). Vancomycin or teicoplanin resistances were not detected. Most isolates (especially E. faecalis) were proteolytic and carried the gelatinase gene gelE. Genes encoding other potential virulence factors (ace, efaA (fs), ccf and cpd) were frequently detected. Cytolysin genes were mainly detected in a few haemolytic E. faecium isolates, three of which also carried the collagen adhesin acm gene. Hyaluronidase gene (hyl ( Efm )) was detected in two isolates. Many isolates produced bacteriocins and carried genes for enterocins A, B, and L50 mainly. The similarities found between enterococci from wild flowers and those from animal and food sources raise new questions about the puzzling lifestyle of these commensals and opportunistic pathogens.

Presence of glycopeptide-encoding plasmids in enterococcal isolates from food and humans in Denmark.

Enterococci and especially glycopeptides-resistant enterococci (GRE) are a growing concern due to their ability to cause infections in hospitals. Transmission of antimicrobial resistance between reservoirs such as animals, meat, and humans are in most cases linked to transmission of mobile genetic elements (MGE) such as plasmids and transposons. Presence of MGE was tested in all GRE isolated from food in Denmark in 2005-2007 including the first vanA mediated Enterococcus faecalis isolated from food. The ability of these plasmids to transfer and persist among enterococci was investigated using newly developed techniques for classification of plasmids. Replicons associated with sex pheromone-inducible plasmids were detected in all GR E. faecalis, whereas GR Enterococcus faecium contained plasmids known to be widely distributed among enterococci. vanA resistance is common in E. faecium isolates from meat and animals in Europe and is rarely found in E. faecalis. This article describes the first characterization of MGE from vanA mediated E. faecalis, thus linking this resistance genotype to pheromone responding plasmids.

[The effectiveness of the percutaneous discectomy in the treatment of pain secondary to disc herniation]. / Discectomía percutánea para tratamiento del dolor radicular.

BACKGROUND: Percutaneous discectomy has shown to be useful for relief the radicular pain due to a disk hernia, which is a common condition in the general population. The objective was to evaluate the efficacy of percutaneous discectomy in radicular pain caused by disk hernia. METHODS: A descriptive study was done. The records of percutaneous discectomy patients from a two years period were analyzed including those who had a pain intensity scored by a Analog Visual Scale (VAS), those with daily taken analgesics, before and after the procedure were registered. Dose in milligrams (mg) of analgesic intake were converted to equivalent dosages for 24 hours oral morphine. Pain intensity and medication take before and after the procedure were compared. RESULTS: VAS average previous to the procedure was 6.29 and after it descended to 2.86. The mean of medication intake before discectomy was 30.32 mg and after the procedure was 12.75 mg. DISCUSSION: We found pain improvement in a high percentage of patients reflected by a decrease in VAS and the medication needed.

Isolation and identification of Enterococcus faecium from seafoods: antimicrobial resistance and production of bacteriocin-like substances.

A collection of isolates from uncooked seafoods (molluscs, fish, and fish fillets) were identified as Enterococcus faecium species and studied in further detail. Isolates were clustered in well-defined genomic groups according to food origin after ERIC-PCR analysis. Four isolates (FR 1-2, FB 1-3-B, FB 3-1, FTA 1-2) decarboxylated lysine, ornithine, and tyrosine. Isolate FR 1-2 also decarboxylated histidine. Most isolates were sensitive to antibiotics of clinical use, but resistance was detected more frequently towards nitrofurantoin (50%), erythromycin (33.33%) or rifampicin (33.33%) to quinupristin/dalfopristin (12.5%). Resistance to beta-lactams or vancomycin was not detected. The enterococcal antigen A was the presumed virulence trait detected most frequently. None of isolates carried haemolysin/cytolysin genes. Twelve isolates produced anti-listerial activity. Among them, seven isolates also produced bacteriocin-like inhibitory substances against other enterococci, and one isolate was also able to inhibit Staphylococcus aureus. Three isolates only were active against Listeria monocytogenes, and two only were active against enterococci. One bacteriocinogenic isolate carried the enterocin A structural gene, but genes corresponding to other enterocins (EntB, EntP, EntQ, Ent1071, EntL50A/EntL50B, and Ent31) were not detected. Bacteriocin-producing enterococci lacking undesirable traits (such as antibiotic resistance or biogenic amine production) or their produced bacteriocins could be potential candidates to aid in preservation of seafoods and other food products as well.

Bacteriocin-producing Lactobacillus strains isolated from poto poto, a Congolese fermented maize product, and genetic fingerprinting of their plantaricin operons.

Thirty one bacteriocin-producing Lactobacillus isolates were identified among 135 lactobacilli isolated from the Congolese fermented maize product poto poto, during the preparation and from the finished product. Using species-specific PCR and 16S rRNA gene sequencing, 28 and 3 isolates were identified as L. plantarum and L. fermentum, respectively. Cluster analysis of RAPD-PCR fingerprints revealed two main groups (G1 and G2) plus the L. fermentum isolate C4-13. Group G1 contained 23 isolates with a similarity coefficient > 74.5%, and could be divided in two subgroups (G1-1, G1-2) each with several branches, plus the L. plantarum isolate C11. Group G2 contained 8 isolates with a similarity coefficient > 86%, with two main branches. Using PCR amplification with specific primers, several genes of the plantaricin cluster found in L. plantarum C11 were identified in the isolates. The number of genes that were detected varied between the strains. The L. fermentum isolate EC11 also contained the plnDEFG genes. PCR amplification of DNA from isolates with primers directed to the upstream and downstream region of the plantaricin cluster generated an amplicon identical to that obtained with DNA from the control strain L. plantarum WCFS1. Amplification products from the positive strains were used for restriction analysis with HindIII, EcoRI and KpnI in separate reactions. Cluster analysis of restriction profiles revealed high similarities for EcoRI and HindII digest profiles, and an identical profile for all KpnI digests. The L. fermentum EC11 isolate clustered with L. plantarum strains in a group with a high correlation coefficient. The results suggest a low degree of diversity in the plantarincin gene cluster. However, other strains that tested positive for individual plantaricin genes may present great heterogeneity in the plantaricin operons. Because of their broad spectra of inhibition (including Escherichia coli, Salmonella enterica, Enterobacter aerogenes, Bacillus cereus, Staphylococcus aureus, Listeria monocytogenes, and Enterococcus faecalis), isolates from the present study could be used to improve the safety and storage stability of poto poto.

Risk factors in enterococci isolated from foods in Morocco: determination of antimicrobial resistance and incidence of virulence traits.

A collection of enterococci isolated from meat, dairy and vegetable foods from Morocco including 23 Enterococus faecalis and 15 Enterococcus faecium isolates was studied. All isolates were sensitive to ampicillin, penicillin, and gentamicin. Many E. faecalis isolates were resistant to tetracycline (86.95%), followed by rifampicin (78.26% ciprofloxacin (60.87%), quinupristin/dalfopristin (56.52%), nitrofurantoin (43.47%), levofloxacin (39.13%), erythromycin (21.73%), streptomycin (17.39%), chloramphenicol (8.69%), vancomycin (8.69%), and teicoplanin (4.34%). E. faecium isolates showed a different antibiotic resistance profile: a high percentage were resistant to nitrofurantoin (73.33%), followed by erythromycin (66.60%), ciprofloxacin (66.66%), levofloxacin (60.00%), and rifampicin (26.66%), and only a very low percentage were resistant to tetracycline (6.66%). One isolate was resistant to vancomycin and teicoplanin. The incidence of virulence factors was much higher among E. faecalis isolates, especially for genes encoding for sex pheromones, collagen adhesin, enterococcal endocarditis antigen, and enterococcal surface protein. Isolates with multiple factors (both antibiotic resistance and virulence traits) were also more frequent among E. faecalis isolates, in which one isolate cumulated up to 15 traits. By contrast, several isolates of E. faecium had only very few unwanted traits as compared to only two isolates in E. faecalis. The high abundance of isolates carrying virulence factors and antibiotic resistance traits suggests that the sanitary quality of foods should be improved in order to decrease the incidence of enterococci.

[Clinical pattern of patients cared for at pain clinic by first time]. / Característkicas de los enfermos que acuden a clínicas del dolor por primera vez.

BACKGROUND: Epidemiological studies about frequency and prevalence of chronic pain in Mexico are scarce. However, it has been documented that chronic pain is a frequent complain in general population and mainly in older adults. It influences physical patient capacity and it impacts social health services with its expensive cost. Our objective was to identify the clinical pattern of patients attending at a Pain Clinic by first time. METHODS: We conducted a descriptive-retrospective study, in a five years period, with patients attending a Pain Clinic by first time. We collected demographic data and information about the cause of pain (malignant vs. non-malignant etiology), its intensity by visual analogue scale (VAS), and type (somatic, visceral, neuropathic and mixed). RESULTS: 1453 clinical records were analyzed. Women were more affected; the average age was 59 +/- 16 years; non-malignant pain and neuropathic pain were more frequent; the intensity average was 6 +/- 2, and it increases with age. CONCLUSIONS: It is necessary to generate epidemiological studies to fundament health policies regarding the management of these patients.