Differences in anti-malarial activity of 4-aminoalcohol quinoline enantiomers and investigation of the presumed underlying mechanism of action

International audienc

CARB-ES-19 Multicenter Study of Carbapenemase-Producing Klebsiella pneumoniae and Escherichia coli From All Spanish Provinces Reveals Interregional Spread of High-Risk Clones Such as ST307/OXA-48 and ST512/KPC-3

ObjectivesCARB-ES-19 is a comprehensive, multicenter, nationwide study integrating whole-genome sequencing (WGS) in the surveillance of carbapenemase-producing K. pneumoniae (CP-Kpn) and E. coli (CP-Eco) to determine their incidence, geographical distribution, phylogeny, and resistance mechanisms in Spain.MethodsIn total, 71 hospitals, representing all 50 Spanish provinces, collected the first 10 isolates per hospital (February to May 2019); CPE isolates were first identified according to EUCAST (meropenem MIC > 0.12 mg/L with immunochromatography, colorimetric tests, carbapenem inactivation, or carbapenem hydrolysis with MALDI-TOF). Prevalence and incidence were calculated according to population denominators. Antibiotic susceptibility testing was performed using the microdilution method (EUCAST). All 403 isolates collected were sequenced for high-resolution single-nucleotide polymorphism (SNP) typing, core genome multilocus sequence typing (cgMLST), and resistome analysis.ResultsIn total, 377 (93.5%) CP-Kpn and 26 (6.5%) CP-Eco isolates were collected from 62 (87.3%) hospitals in 46 (92%) provinces. CP-Kpn was more prevalent in the blood (5.8%, 50/853) than in the urine (1.4%, 201/14,464). The cumulative incidence for both CP-Kpn and CP-Eco was 0.05 per 100 admitted patients. The main carbapenemase genes identified in CP-Kpn were blaOXA–48 (263/377), blaKPC–3 (62/377), blaVIM–1 (28/377), and blaNDM–1 (12/377). All isolates were susceptible to at least two antibiotics. Interregional dissemination of eight high-risk CP-Kpn clones was detected, mainly ST307/OXA-48 (16.4%), ST11/OXA-48 (16.4%), and ST512-ST258/KPC (13.8%). ST512/KPC and ST15/OXA-48 were the most frequent bacteremia-causative clones. The average number of acquired resistance genes was higher in CP-Kpn (7.9) than in CP-Eco (5.5).ConclusionThis study serves as a first step toward WGS integration in the surveillance of carbapenemase-producing Enterobacterales in Spain. We detected important epidemiological changes, including increased CP-Kpn and CP-Eco prevalence and incidence compared to previous studies, wide interregional dissemination, and increased dissemination of high-risk clones, such as ST307/OXA-48 and ST512/KPC-3

Producción de tensioactivos con actividad antimicrobiana mediante el empleo de tecnologías amigables con el medio ambiente

Papaína es una endopeptidasa extraída del látex de frutos de Carica papaya ampliamente empleada en las industrias alimentaria y farmacéutica. Es muy utilizada como biocatalizador en la síntesis de péptidos y otros derivados. Los surfactantes derivados de arginina son una familia de tensioactivos catiónicos con propiedades antimicrobianas interesantes como preservativos para formulaciones farmacéuticas y alimentarias.El objetivo del presente trabajo fue la obtención, purificación y determinación del poder antimicrobiano de un compuesto derivado de arginina con potencial actividad tensioactiva, sintetizado mediante el empleo de papaína como biocatalizador.La síntesis se llevó a cabo por condensación del éster etílico de N?-benzoil-arginina con dodecilamina como nucleófilo, utilizando papaína adsorbida sobre poliamida como biocatalizador y acetonitrilo con 0.25% (v/v) de agua como medio de reacción. El producto (Bz-Arg-NHC12) fue purificado mediante cromatografía de intercambio catiónico utilizando como eluyente una mezcla de buffer bórico-borato 0.01 M (pH 8.5)/etanol (1:1) y un gradiente en NaCl. Se ensayó la actividad antimicrobiana mediante el método de microdilución frente a Salmonella enterica, Serratia marcescens, Shigella flexneri, Escherichia coli, Pseudomonas aeruginosa, Bacillus cereus, Bacillus subtilis, Staphylococcus aureus, Enterococcus faecalis, Enterococcus faecium, Kocuria rhizophila, Listeria innocua, Listeria monocytogenes, Pichia anomala, Saccharomyces cereviciae, Kluyveromyces marxianus y Rhodothorula sp., calculándose los porcentajes de inhibición de crecimiento y las concentraciones inhibitoria mínima (CIM) y bactericida mínima (CBM).La síntesis de Bz-Arg-NHC12 catalizada por papaína adsorbida en poliamida tuvo una conversión del 86.2%. Se determinó la actividad antimicrobiana de una solución acuosa de Bz-Arg-NHC12 (60.0 ?g.ml-1) frente a distintas especies de bacterias y levaduras. Los microorganismos Gram positivos resultaron en general inhibidos en más de un 90%, en tanto las bacterias Gram negativas y levaduras ensayadas fueron resistentes.El compuesto puro presentó una CIM de 15.6 ?g.ml-1 para B. cereus, 62.5 ?g.ml-1 para St. aureus y 250.0 ?g.ml-1 para E. coli, en tanto que no afectó el crecimiento de Ps. aeruginosa. Las CBM fueron 250.0 ?g.ml-1, 62.5 ?g.ml-1 y 250.0 ?g.ml-1 para B. cereus, St. aureus y E. coli respectivamente

Developing dialogic classroom practices through supporting professional agency: Teachers’ experiences of using the T-SEDA practitioner-led inquiry approach

Classroom dialogue is considered productive for learning but rarely observed, and practitioner professional development is needed. This study investigated how 67 teachers across educational phases in six countries contextualised the T-SEDA inquiry toolkit to conduct classroom inquiries and develop new practices. Surveys and inquiry reports yielded insights into how practitioner agency was further developed, with implications for sustainability. Change was evident in self-reported enhanced awareness and understanding of dialogue and use of dialogic strategies. Increases in students’ dialogic participation and plans for dissemination to colleagues were reported

Study ofbrídge foundation with GPR

Ground penetrating radar is usually employed for non-destructive evaluations and maintenance of roads and bridges. This report describe the study of an emlbankmet where a bridge will be built due to the construction of a new road. The geology In this place, where the foundations of the bridge will be emplaced, are formed by hint sands layers between conglomerates ones. Flowing water eroses the sand causing holes and possible landslides, which could be damaging for the bridge. The study of the embakment with aground penetrating radar allows to know the thickness o f the sand layers and the posible holes placed into them. An antenna with center frecuency 100 MHz was used attending the characteristics o f the emplacement. The radar data shows among some other things, the different reflectors due to the conglomerate, the sand layers and their thicknesses. The presence and the emplacement of several holes in the layers are also observed. These results show where the foundations must be properly placed. A comparison with a geological profile was perfomed to assure the result

GPR measurements to study an abandoned salt mine for tourlstlcal purposes

The opening of abandoned salt mines whit the idea of prepare cultural routes requires the use of hard machinery in abandoned places. The erosion caused by salt disolutions damage the mine structure, being dangerous for restoration and visiting purposes. Planed jobs were the opening of a new gallery to prepare a round route and restoring the part of the salt mine that will be open to the public. Ground penetrating measurements have been used, first to locate the position and depth of underground scour holes and subsurface voids in the ground and in the solid salt mountain, and second, to study the vault and gables end in the salt mine galleries. Three antennas were used in his job, with WO MHz, 300 MHz and 500 MHz center frecuencies.. Radar data has locate holes in the first meters under the floor of the mine galleries and into the contact between the salt mountain and the cover materials. The analisys of the anomalies also shows scour holes in to the slag heap caused by the flowing water which eroses the soft materials. These areas are not safety places for mining jobs. This work try to provide safety measurements to the salt mine workers and try to assists to the tourist mine maintenance plannin

Jet-grouting determination in a subway metropolitan tunnel by using ground penetrating radar analysis

Several kilometers o f tunnel have been excavated to extend a metropolitan underground system. In some places, where the subsurface is mainly composed by gravel and sands, water can easly penetrate causing problems to the tunnel and the stations. In order to avoid such problems, a jet-grouting injection was carried out. To check the continuity of the jet-grouting a Ground Penetrating Radar analysis was applied. The radar used is a SIR 10 of Geophysical Survey Systems Inc., with a center frecuency antenna of 100 Mz, prepared for urban jobs. A good determination of the variantion of the thickness of the jet-grouting layer was obtained, although several difficulties, specially the irregular topography, were to be solved. Three boreholes to determine the quality and thickness of the jet-grouting in three different places provided the right calibration of the involved radargrams. During the processing of the data, several filters had to be applied to discriminate the radar signals from noise, coming mainly from the electrical system of the tunne

Georadar applications on concrete reinforced walls into a nuclear power plant

Accurate identification of frames into concrete reinforced walls in a nuclear power plant was required because of maintenance labours. Several cuts in the concrete, including the frame, were planned. The cutting lines were designed to avoid as much as possible the frame bars. To perfom this work the ground penetrating radar has been used. The use of ground prenetrating radar techniques allow to determine the vertical and horizontal position of the frame bars. GPR detects also other reflectors in to the walls. The ele ctric propertie s contrast betw een the concrete and th e steel o f the frame gives reflections clearly detected in the records. This near surface study requires to use high resolution antennas with a very high center frecuency. The measurement precision required In the work was obtained using a special marker to carry the antenna, specially design for this job. The marker allows to know the position of the antenna on the wall with a precission of centimeters. The measurements were acquired from one antenna with a center frecuency of 1000 MHz, with a SIR 10 system of Geophysical Survey Sistems Inc.. An experimental test made in a scale model help to the interpretation of the records.. A later and careful treatment in laboratory, using all the records obtained in the nuclear power plant, applying vertical lowpass and highpass filters and horizontal lowpass filter was perfomed, to place correctly the bars into the concret

Syntheses of dipeptide alcohols and dipeptide aldehyde precursors catalyzed by plant cysteine peptidases

Two different cysteine peptidases obtained from plant latex (papain from Carica papaya and araujiain from Araujia hortorum) demonstrated to be good catalysts for the condensation of coded and non-coded Cbz-amino acids and amines such as amino alcohols and amino acetals in acetonitrile containing 1% (v/v) water. Both kinetically and thermodynamically controlled syntheses were proved. Thermodynamic approach was selected since the conversions in product found were similar to those obtained by the kinetic approach; furthermore, a minor number of synthetic steps were needed. For the Cbz-amino acids tested, conversions were higher than 80% at 48–72 h of reaction, except for the Phg derivative, which produced conversions of ca. 40 and 20% for papain and araujiain, respectively. Product yields for the scaled up reactions were similar to the conversions obtained in microscale synthesis. The flexibility of both enzymes for the nucleophile allowed the condensation reaction of Cbz-Ala-OH with an amino diacetal derivative. The resulting dipeptide diacetal derivative can be easily tranformed into a dipeptide aldehyde by acid hydrolysis.Centro de Investigación de Proteínas Vegetale