Search

INTRODUCCIÓN: El entorno escolar juega un rol importante para prevenir la malnutrición en la infancia. El objetivo fue evaluar la disponibilidad de agua potable en la cocina, la oferta durante el almuerzo y la jornada escolar y la presencia de kioscos en escuelas públicas de la provincia de Buenos Aires según prestación alimentaria y necesidades básicas insatisfechas (NBI). MÉTODOS: Se realizó un análisis post hoc de la Encuesta del Servicio Alimentario Escolar 2016-2019 de una muestra de 3342 escuelas iniciales, primarias y secundarias. Se evaluó el suministro de agua en la cocina, las fuentes de agua potable para los alumnos, la bebida en el almuerzo y la disponibilidad de kiosco. Las variables se analizaron por nivel educativo y se estratificaron según la prestación alimentaria. Se realizó un análisis estadístico descriptivo. RESULTADOS: Alrededor del 1% (n=30) de las escuelas no contaban con agua potable en la cocina, y no se observaron diferencias porcentuales por prestación ni tertil de NBI. El 10% de las escuelas no ofrecía bebida en el almuerzo, y 7 de cada 10 no disponía de fuente de agua potable accesible; 4 de cada 10 primarias y secundarias presentaron kiosco. Al evaluar según NBI, la proporción de escuelas con kiosco decrecía a medida que aumentaba el tertil. DISCUSIÓN: Es fundamental generar políticas de regulación del entorno escolar con un enfoque integral y sistémico para prevenir la malnutrición en la población infantil más vulnerable. more...

Abstract Emotions and behavior can be affected by social chemosignals from conspecifics. For instance, olfactory signals from stressed individuals induce stress-like physiological and synaptic changes in naïve partners. Direct stress also alters cognition, but the impact of socially transmitted stress on memory processes is currently unknown. Here we show that exposure to chemosignals produced by stressed individuals is sufficient to impair memory retrieval in unstressed male mice. This requires astrocyte control of information in the olfactory bulb mediated by mitochondria-associated CB1 receptors (mtCB1). Targeted genetic manipulations, in vivo Ca2+ imaging and behavioral analyses reveal that mtCB1-dependent control of mitochondrial Ca2+ dynamics is necessary to process olfactory information from stressed partners and to define their cognitive consequences. Thus, olfactory bulb astrocytes provide a link between social odors and their behavioral meaning. more...

Abstract Background Surgeries for sarcomas in the abdominal wall require wide resections, often radical en bloc resections, which generate major defects involving a very complex repair. The combined use of porcine dermal xenografts, together with composite meshes, may assist in the repair of these defects with minimal complications. Method We present a series of 19 patients (10 males and 9 females), with a mean age of 53.2 years (range: 11–86 years) treated in the Sarcoma Unit of the Virgen de la Arrixaca University Hospital from January 2015 to December 2021. Histopathologically, there were four chondrosarcomas (21%), three Ewing sarcomas (15.7%), two desmoid tumours (10.5%), two undifferentiated pleomorphic sarcomas (10.5%), two well-differentiated liposarcomas (10.5%), two leiomyosarcomas (10.5%), one synovial sarcoma, one dermatofibrosarcoma protuberans, one fibromyxoid sarcoma (or Evans tumour), and one metastasis from an adenocarcinoma of unknown origin. All the patients were resected following surgical oncology principles and reconstructed by means of the combined use of a composite mesh acting as a neoperitoneum and a porcine dermal xenograft acting as an abdominal neofascia. Results The mean size of the defects generated after surgery for tumour excision was 262.8 cm2 (range: 150–600 cm2). After a mean follow-up of 38 months, six patients (31.5%) developed complications—two cases of wound dehiscence, one case of surgical wound infection, one case of graft partial necrosis, one case of anastomotic leak and one death due to multiorgan failure secondary to massive bronchoaspiration. Conclusion Surgeries for sarcomas of the abdominal wall require wide oncological resections, which generate major abdominal wall defects. The repair of these defects by means of the combined use of synthetic and biological meshes is a technique associated with minimal complications and excellent medium-term results. more...

The necropolis from Jebel al Khudairah, located in the Central Region of the Emirate of Sharjah (United Arab Emirates) witnessed excavations in 2020 and 2023 from members of the Spanish Archaeological and Archaeobiological Mission at Sharjah, drawn from Universidad Autónoma de Madrid. In this paper we present a preliminary overview of the results from these two field seasons after completing excavations of five tombs of very diverse types, located in several sectors of the jebel. Only one of them provided remains of burials of at least two individuals accompanied by a metal arrowhead. Nevertheless, the preliminary comparative analysis of the architecture of the structures as well as of the only datable find, allows one to make some suggestions concerning the chronological span of the necropolis. more...

Biodegradable biopolymers from species of the animal kingdom or their byproducts are sustainable as ecological materials due to their abundant supply and compatibility with the environment. The research aims to obtain a biodegradable active material from chitosan, gelatin, and collagen from bocachico scales (Prochilodus magdalenae). Regarding the methodology, films were developed from gelatin, chitosan, and collagen from bocachico scales (Prochilodus magdalenae) at different concentrations using glycerol as a plasticizer and citric acid as a cross-linker. The films were obtained with the hydrated mass processed by compression molding and characterized according to humidity, water solubility, contact angle, mechanical properties, and structural properties. The results of the films showed a hydrophobic characteristic. First, the chitosan-collagen (CS/CO) films showed a yellowish color, while the gelatin-collagen (Gel/CO) films were transparent and less soluble than the gelatin-collagen (Gel/CO) films. Concerning mechanical properties, gelatin films showed higher stiffness and tensile strength than chitosan films. Furthermore, in the morphological analysis, more homogeneous chitosan films were obtained by increasing the concentration of citric acid. In general, chitosan, gelatin, and collagen extracted from the scales of the bocachico (Prochilodus magdalenae) are an alternative in the application of films in the food industry. more...

Estimados editores: El cáncer de tiroides es una patología poco frecuente dentro de las dos primeras décadas de la vida, predomina en el sexo femenino y el tipo histológico es en la mayoría de los casos carcinoma papilar1-6. more...

Este trabajo define las principales características sedimentológicas, paleontológicas y geoquímicas de la Unidad Arenas de Trigueros, depositada durante el Messiniense en un contexto global de bajada de nivel del mar. Esta unidad se diferencia del resto de la Formación Arcillas de Gibraleón por su mayor tamaño de grano, la presencia de niveles tempestíticos formados por bivalvos típicos de medios circalitorales, una asociación de ostrácodos propia de medios infralitorales en su tramo superior arenoso y unos menores contenidos en elementos trazas y tierras raras. En su conjunto, estas características identificarían un depósito de turbiditas en un medio circalitoral de baja energía, cuyo fondo sufrió episodios erosivos y donde concurrieron también sedimentos transportados desde medios neríticos someros, dentro de una zona distal de aparatos deltaicos. more...

Abstract In the Iberian Peninsula the fossil record of artiodactyls spans over 53 million years. During the Pleistocene, wild cattle species such as Bison and especially Bos became common. In Late Pleistocene, the aurochs (Bos primigenius) was widespread and the only bovine living along the large river valleys of southern Iberia. Although commonly found in fossil sites and especially in cave bone assemblages, the trace fossil record of aurochs was known worldwide only from the Holocene. Large bovine and roe deer/caprine tracks were found in at least five horizons of the early Late Pleistocene (MIS 5) beach and eolian deposits of Cape Trafalgar (Cadiz Province, South of Spain). The large bovine tracks are formally described as Bovinichnus uripeda igen. et isp. nov. and compared with the record of aurochs tracks, large red deer tracks and steppe bison biogeographical distribution in Iberia. Aurochs were the most likely producers of the newly described Trafalgar Trampled Surface (TTS) and some of the large artiodactyl tracks in the Matalascañas Trampled Surface, representing the oldest aurochs track record known. This new evidence, together with comparisons with the record of possible aurochs tracks in the Mid-Late Pleistocene coastal deposits from the Asperillo cliff section in Matalascañas (Huelva Province, SW Spain) and bone assemblages known in Gibraltar, point to a recurrent use of the coastal habitat by these large artiodactyls in SW Iberia. more...

INTRODUCCIÓN: La industria alimentaria utiliza la televisión como medio para promocionar sus productos. El objetivo fue evaluar la frecuencia y la calidad nutricional de los alimentos publicitados en canales privados de televisión abierta en la Ciudad Autónoma de Buenos Aires. MÉTODOS: Se realizó un estudio descriptivo y transversal. Se analizaron las publicidades de alimentos emitidas en los canales privados de televisión abierta. Se grabó la programación en días de semana y fin de semana de 8 a 20 horas durante agosto y septiembre de 2018. La calidad nutricional se evaluó con el sistema de perfilado nutricional (SPN) utilizado en la Ley Nº 20606 de Chile. RESULTADOS: Se analizaron 220 horas de programación. Se identificó un total de 484 publicidades de alimentos (12,8% de las publicidades), con una frecuencia de 2,2 anuncios por hora de programación. Las golosinas mostraron la mayor frecuencia (28% de los anuncios), seguidas por galletitas dulces (17%) y sopas deshidratadas (7%). De acuerdo con el SPN utilizado, el 55% de los alimentos superó el límite de energía, el 56% el de azúcares totales, el 57% el de grasas saturadas y el 20% el de sodio. DISCUSIÓN: Las publicidades de alimentos ocuparon una décima parte del espacio publicitario. Más de la mitad superó el límite de energía, azúcares totales y grasas saturadas según el sistema de perfilado chileno. more...

Parental food provisioning is crucial for the growth and survival of offspring. Growth rate depends on food quality and food supplied to offspring may differ from what adults use for their own. In the case of steppe passerine birds, detailed characterization on nestling dietary composition, as well as prey choice and resource partitioning among species, is a pending subject. Dietary differences between nestlings and adults remain also largely unexplored. By using faecal DNA metabarcoding, we described the diet of nestlings and adults of five shrub-steppe passerine species over the 2017–2019 breeding seasons in central Spain. We also monitored arthropod availability in the field to assess dietary selection. We expected interspecific dietary differences to limit competition for food resources among sympatric species, as well as parental selection of high quality prey for nestlings. We also predicted age-related differences, with nestlings being fed nutrient-rich prey more frequently than adults. The main arthropod orders provisioned to nestlings were Orthoptera, Julida, Araneae and Lepidoptera. Nestlings of the different species showed high interspecific diet overlap, indicating both a coincidence in growth needs among bird species and no or little limitation of the most profitable resources during the breeding season. Adults of all species showed higher diet richness than nestlings, and age-related differences in prey composition were mainly driven by the selection of the most easily digestible, larger protein- and calcium-rich prey for nestlings, which may favour their rapid growth, and avoiding highly sclerotized and less nutritional prey such as ants. Our study sheds light on the basic ecology and conservation of these declining steppe birds, indicating that interspecific competition may not be a major factor during the breeding season. Given the current global decline of arthropods, further long-term research would be necessary, along with the implementation of effective conservation measures that ensure a sufficient availability of resources identified as key prey in the diet of steppe bird nestlings. more...

Estuaries are excellent environments for identifying pollution episodes that have affected river basins, as their sediments are the final destination of some of the pollutants. This paper studies the geochemical evolution of five elements (As, Co, Cu, Pb, Zn) in a core extracted from the middle estuary of the Tinto River (SW Spain). The results are based on facies interpretation, ICP atomic emission spectrometry analysis, the application of a regional background to obtain the geoaccumulation index and dating. The main objective of this communication is the detection of natural or anthropogenic pollution episodes in the middle estuary of the Tinto River (SW Spain). Four pollution episodes have been detected: (1) ~5.8 cal. kyr BP, probably caused by natural acid rock drainage processes derived from the oxidation of the Iberian Pyritic Belt deposits found in its drainage basin; (2) 4.7–4.5 kyr BP, coming from the first mining activities and characterized by a significant increase in the concentrations of the five elements analyzed; (3) 1850–1960 interval, coinciding with intensive mining and characterized by increasing values of As and, to a lesser extent, Pb (intensive mining); and (4) the second half of the 20th century, with high element concentrations from mining and industrial effluents. All episodes show an increase in their geochemical classes deduced from the geoaccumulation index. This communication can serve as an example for assessing the impact of different types of pollution in estuarine environments. more...

In men, prostate cancer is the most frequently diagnosed malignancy worldwide. Early diagnosis improves its prognosis, with higher survival rates and a better quality of life for patients. However, diagnosis and characterization of tumors are mainly based on highly invasive tissue biopsies, with an incomplete representation of the entire tumor. In consequence, attention is turning to the so-called liquid biopsies, which provide molecular information about the tumor by detecting its specific components, including proteins, circulating nucleic acids or tumor cells, in bodily fluids such as blood or urine. Recent years have seen the development of a large number of electrochemical sensors employing oligonucleotides for the recognition of prostate tumor components in a minimal invasive way. Here we survey the reported designs, which are categorized as aptasensors and genosensors for the different molecular components identified as prostate cancer biomarkers. We present a critical evaluation of their analytical validity, identifying the challenges of bringing these devices to the clinical practice. more...

Abstract Tracks and trackways of newborns, calves and juveniles attributed to straight-tusked elephants were found in the MIS 5 site (Upper Pleistocene) known as the Matalascañas Trampled Surface (MTS) at Huelva, SW Spain. Evidence of a snapshot of social behaviour, especially parental care, can be determined from the concentration of elephant tracks and trackways, and especially from apparently contemporaneous converging trackways, of small juvenile and larger, presumably young adult female tracks. The size frequency of the tracks enabled us to infer body mass and age distribution of the animals that crossed the MTS. Comparisons of the MTS demographic frequency with the morphology of the fore- and hind limbs of extant and fossil proboscideans shed light into the reproductive ecology of the straight-tusked elephant, Palaeloxodon antiquus. The interdune pond habitat appeared to have been an important water and food resource for matriarchal herds of straight-tusked elephants and likely functioned as a reproductive habitat, with only the rare presence of adult and older males in the MTS. The preservation of this track record in across a paleosol surface, although heavily trampled by different animals, including Neanderthals, over a short time frame, permitted an exceptional view into short-term intraspecific trophic interactions occurring in the Last Interglacial coastal habitat. Therefore, it is hypothesized that Neanderthals visited MTS for hunting or scavenging on weakened or dead elephants, and more likely calves. more...

Abstract Bone morphogenetic protein (Bmp) signaling is critical for organismal development and homeostasis. To elucidate Bmp2 function in the vascular/hematopoietic lineages we generated a new transgenic mouse line in which ectopic Bmp2 expression is controlled by the Tie2 promoter. Tie2 CRE/+ ;Bmp2 tg/tg mice develop aortic valve dysfunction postnatally, accompanied by pre-calcific lesion formation in valve leaflets. Remarkably, Tie2 CRE/+ ;Bmp2 tg/tg mice develop extensive soft tissue bone formation typical of acquired forms of heterotopic ossification (HO) and genetic bone disorders, such as Fibrodysplasia Ossificans Progressiva (FOP). Ectopic ossification in Tie2 CRE/+ ;Bmp2 tg/tg transgenic animals is accompanied by increased bone marrow hematopoietic, fibroblast and osteoblast precursors and circulating pro-inflammatory cells. Transplanting wild-type bone marrow hematopoietic stem cells into lethally irradiated Tie2 CRE/+ ;Bmp2 tg/tg mice significantly delays HO onset but does not prevent it. Moreover, transplanting Bmp2-transgenic bone marrow into wild-type recipients does not result in HO, but hematopoietic progenitors contribute to inflammation and ectopic bone marrow colonization rather than to endochondral ossification. Conversely, aberrant Bmp2 signaling activity is associated with fibroblast accumulation, skeletal muscle fiber damage, and expansion of a Tie2+ fibro-adipogenic precursor cell population, suggesting that ectopic bone derives from a skeletal muscle resident osteoprogenitor cell origin. Thus, Tie2 CRE/+ ;Bmp2 tg/tg mice recapitulate HO pathophysiology, and might represent a useful model to investigate therapies seeking to mitigate disorders associated with aberrant extra-skeletal bone formation. more...

This paper investigates the paleoenvironmental evolution of a core extracted in the middle sector of the Tinto River estuary, SW Spain, one of the most polluted areas in the world due to mining over thousands of years (>4 kyr BP) and recent industrial discharges. This evolution includes alluvial sands (>6.4 cal kyr BP), bioclastic sands and silts deposited in subtidal and intertidal channels during and after the Holocene transgression maximum (6.4-4.3 cal kyr BP), the sedimentation of clayey-sandy silts in low and high marshes during the last 2.4 kyr BP and a final anthropic filling. Three sharp peaks of pollution have been detected, representing a) a natural origin during the Holocene transgression; b) the impact of the first mining activities (~4.5 cal kyr BP); and c) the effect of industrial discharge and a new period of mining activity throughout the 19th and 20th centuries. Foraminifera, ostracods and molluscs disappeared during these last two peaks. more...

Most methicillin resistant Staphylococcus aureus (MRSA) isolates harboring mecC gene belong to clonal complex CC130. This lineage has traditionally been regarded as animal-associated as it lacks the human specific immune evasion cluster (IEC), and has been recovered from a broad range of animal hosts. Nevertheless, sporadic mecC-MRSA human infections have been reported, with evidence of zoonotic transmission in some cases. The objective of this study was to investigate the whole-genome sequences of 18 S. aureus CC130 isolates [13 methicillin-resistant (mecC-MRSA) and five methicillin-susceptible (MSSA)] from different sequences types, obtained from a variety of host species and origins (human, livestock, wild birds and mammals, and water), and from different geographic locations, in order to identify characteristic markers and genomic features. Antibiotic resistance genes found among MRSA-CC130 were those associated with the SSCmecXI element. Most MRSA-CC130 strains carried a similar virulence gene profile. Additionally, six MRSA-CC130 possessed scn-sak and one MSSA-ST130 had lukMF’. The MSSA-ST700 strains were most divergent in their resistance and virulence genes. The pan-genome analysis showed that 29 genes were present solely in MRSA-CC130 (associated with SCCmecXI) and 21 among MSSA-CC130 isolates (associated with phages). The SCCmecXI, PBP3, GdpP, and AcrB were identical at the amino acid level in all strains, but some differences were found in PBP1, PBP2, PBP4, and YjbH proteins. An examination of the host markers showed that the 3’ region of the bacteriophage φ3 was nearly identical to the reference sequence. Truncated hlb gene was also found in scn-negative strains (two of them carrying sak-type gene). The dtlB gene of wild rabbit isolates included novel mutations. The vwbp gene was found in the three MSSA-ST700 strains from small ruminants and in one MSSA-ST130 from a red deer; these strains also carried a scn-type gene, different from the human and equine variants. Finally, a phylogenetic analysis showed that the three MSSA-ST700 strains and the two MSSA-ST130 strains cluster separately from the remaining MRSA-CC130 strains with the etD2 gene as marker for the main lineage. The presence of the human IEC cluster in some mecC-MRSA-CC130 strains suggests that these isolates may have had a human origin. more...

This article examines the relationship between defence expenditure and its impact on the growth of NATO's countries between 2005 and 2018. The aim is to determine if this relation exists and to test if it is possible to discover different models across the countries. The results obtained using the Arellano-Bond estimator, suggest that there is more than one model, and confirm, through the poolability test, the existence of five different groups of countries within the Alliance, with different impacts of the defence expenditure on their gross domestic product. These findings are in line with the review of existing literature that reveals heterogeneity in the results due to different parameters used. more...

Durante el periodo romano (siglo III a.C.-siglo V d.C.), las zonas próximas a la actual desembocadura del río Guadalquivir estaban ocupadas por una laguna interior con conexión marina, a partir de la interpretación paleoambiental de las asociaciones de foraminíferos bentónicos obtenidos en un sondeo situado en el Parque Nacional de Doñana. Sus zonas internas estaban ocupadas por llanuras mareales arcillosas, que sufrieron los efectos de una tormenta hacia finales del siglo I d.C. La comparación con los ostrácodos del mismo sondeo confirma esta recons­trucción y los datos paleogeográficos aportados por diversos cronistas, si bien estos microcrustáceos detectan de manera más precisa los cambios paleoambientales en estos medios litorales. more...

Every year the world loses about 50% of fruits and vegetables post-harvest and in the supply chain. The use of biodegradable coatings and films with antioxidant properties has been considered an excellent alternative to extend the shelf life of food. Therefore, the objective of this work was to develop a coating based on yam (Dioscorea rotundata L.) starch-containing lime, fennel, and lavender essential oils to extend the shelf life of strawberries (Fragaria vesca l.). The tensile properties, barrier properties (water vapour permeability (WVP) and oxygen permeability (OP)), moisture content, water-solubility, absorption capacity, water contact angle, optical properties, the antioxidant activity of the resultant starch-based coatings were evaluated. After that, the active properties of the coatings were assessed on strawberries inoculated with Aspergillus niger during 14 days of storage at 25 °C. The results showed that the incorporation of essential oils improved the elongation and WVP and provided antioxidant capacity and antimicrobial activity in the films. In particular, the essential oil of lime showed higher antioxidant activity. This fact caused the unwanted modification of other properties, such as the decrease in tensile strength, elastic modulus and increase in OP. The present study revealed the potential use of lime, fennel, and lavender essential oils incorporated into a polymeric yam starch matrix to produce biodegradable active films (antioxidant and antimicrobial). Obtained films showed to be a viable alternative to increase the shelf life of strawberries and protect them against Aspergillus niger. more...

Abstract Background Clostridium difficile infection (CDI) leads to the onset of antibiotic-associated diarrhea (AAD) and a wide range of gastrointestinal pathologies. Currently, CDI is one of the most important opportunistic infections at the intrahospital level and an exponential increase in community-acquired infections has been reported. Herein, we evaluated the relationships (at phylogenetic and genetic population structure levels), as well as the molecular toxigenic and antibiotic resistance profiles of a set of isolates established from a case of community acquired-CDI. Case presentation A 30-year-old woman with no history of hospitalization who was exposed to antibiotics (ampicillin/sulbactam and metronidazole) after a cat-bite wound was presented. The patient had a continuous episode of diarrhea; a stool sample was then collected and community acquired-CDI was confirmed by molecular tests and in vitro culture. Seven isolates were established and subsequently subjected to: (i) Multilocus sequence typing, all isolates belonging to ST-1 (associated with hypervirulent strain (027/BI/NAP1); (ii) description of their toxigenic profile: two of the isolates (Gcol.49 and Gcol.91) were positive for the genes coding for the major toxins (tcdA and tcdB) and their negative regulator (tcdC). All isolates were positive for the cdtB gene encoding one of the binary toxin subunits, while only two (Gcol.51 and Gcol.52) were positive for cdtA; and (iii) identification of antibiotic resistance molecular markers, where there was no difference in gyrA or gyrB gene polymorphisms (related to quinolone resistance), but rather at loci presence/absence, being just one isolate negative, whereas the others showed a differential presence of the tet, ermB and Tn916 regions. The former was associated with resistance to tetracycline and the other two for erythromycin/clindamycin. Conclusions This case represents the first report of community acquired-CDI in Colombia associated with hypervirulent strains and shows that isolates obtained from a single patient can carry different toxin and antibiotic resistance loci. more...

A new methicillin resistance gene, named mecC, was first described in 2011 in both humans and animals. Since then, this gene has been detected in different production and free-living animals and as an agent causing infections in some humans. The possible impact that these isolates can have in clinical settings remains unknown. The current available information about mecC-carrying methicillin resistant S. aureus (MRSA) isolates obtained from human samples was analyzed in order to establish its possible clinical implications as well as to determine the infection types associated with this resistance mechanism, the characteristics of these mecC-carrying isolates, their possible relation with animals and the presence of other risk factors. Until now, most human mecC-MRSA infections have been reported in Europe and mecC-MRSA isolates have been identified belonging to a small number of clonal complexes. Although the prevalence of mecC-MRSA human infections is very low and isolates usually contain few resistance (except for beta-lactams) and virulence genes, first isolates harboring important virulence genes or that are resistant to non-beta lactams have already been described. Moreover, severe and even fatal human infection cases have been detected. mecC-carrying MRSA should be taken into consideration in hospital, veterinary and food safety laboratories and in prevention strategies in order to avoid possible emerging health problems. more...

The objective of this study was to determine the prevalence and diversity of coagulase-negative staphylococci (CoNS) species from wild birds in Spain, as well as to analyze the antimicrobial resistance phenotype/genotype and the virulence gene content. During 2015–2016, tracheal samples of 242 wild birds were collected in different regions of Spain for staphylococci recovery. The species identification was performed using MALDI-TOF. The antimicrobial resistance phenotype and genotype was investigated by the disk diffusion method and by PCR, respectively. The presence of the virulence genes lukF/S-PV, tst, eta, etb, etd and scn was investigated by PCR. Moreover, CoNS carrying the mecA gene were subjected to SCCmec typing. Of the tested animals, 60% were CoNS-carriers, and 173 CoNS isolates were recovered from the 146 positive animals, which belonged to 11 species, with predominance of S. sciuri (n = 118) and S. lentus (n = 25). A total of 34% of CoNS isolates showed a multidrug resistance phenotype, and 42 mecA-positive methicillin-resistant CoNS (MRCoNS) were detected. The isolates showed resistance to the following antimicrobials (percentage of resistant isolates/antimicrobial resistance genes detected): penicillin (49/ blaZ, mecA), cefoxitin (24/ mecA), erythromycin and/or clindamycin (92/ erm(B), erm(C), erm(43), msr(A), mph(C), lnu(A), lsa(B), vga(A) and sal(A)), gentamicin and/or tobramycin (5/ aac(6′)-Ie-aph(2″)-Ia, ant(4′)-Ia), streptomycin (12/str), tetracycline (17/ tet(K), tet(L), tet(M)), ciprofloxacin (4), chloramphenicol (1/ fexA), fusidic acid (86/ fusB, fusD) and trimethoprim–sulfamethoxazole (1/ dfrK). None of the isolates harbored the lukF/S-PV, eta, etb, etd and scn genes, but two S. sciuri isolates (1%) carried the tst gene. Wild birds are frequently colonized by CoNS species, especially S. sciuri. We identified scavenging on intensively produced livestock and feeding on landfills as risk factors for CoNS carriage. High proportions of MRCoNS and multidrug resistant CoNS were detected, which coupled with the presence of important virulence genes is of concern. more...

Methicillin-resistant Staphylococcus aureus (MRSA) sequence type (ST)398 is a livestock associated (LA) lineage with zoonotic potential, especially in humans with live pig contact. The objective of this study was to characterize two S. aureus strains of lineage ST398 (one methicillin-resistant (MRSA), one methicillin-susceptible (MSSA)) isolated from the same nasal sample of a patient admitted in the Intensive-Care Unit of a Spanish Hospital, and with previous occupational exposure to live pigs, by whole-genome-sequencing (WGS). The sample was obtained during routine surveillance for MRSA colonization. Purified genomic DNA was sequenced using Illumina HiSeq 2000 and processed using conventional bioinformatics software. The two isolates recovered were both S. aureus t011/ST398 and showed similar resistance-phenotypes, other than methicillin susceptibility. The possession of antibiotic resistance genes was the same, except for the mecA-gene located in SCCmecV in the MRSA isolate. The MSSA isolate harbored remnants of a SCCmec following the deletion of 17342bp from a recombination between two putative primases. Both isolates belonged to the livestock-associated clade as defined by three canonical single-nucleotide-polymorphisms, and neither possessed the human immune evasion cluster genes, chp, scn, or sak. The core genome alignment showed a similarity of 99.6%, and both isolates harbored the same mobile genetic elements. The two nasal ST398 isolates recovered from the patient with previous occupational exposure to pigs appeared to have a livestock origin and could represent different evolutionary steps of animal-human interface lineage. The MSSA strain was formed as a result of the loss of the mecA gene from the livestock-associated-MRSA lineage. more...

Methicillin-resistant Staphylococcus aureus (MRSA) are one of the main pathogens associated with purulent infections. MRSA clonal complex 97 (CC97) has been identified in a wide diversity of livestock animals. Therefore, we aimed to investigate the antibiotic resistance profiles of MRSA strains isolated from purulent lesions of food-producing rabbits. Samples from purulent lesions of 66 rabbits were collected in a slaughterhouse in Portugal. Samples were seeded onto ORSAB plates with 2 mg/L of oxacillin for MRSA isolation. Susceptibility to antibiotics was tested by the disk diffusion method against 14 antimicrobial agents. The presence of resistance genes, virulence factors and the immune evasion cluster (IEC) system was studied by polymerase chain reaction. All isolates were characterized by multilocus sequence typing (MLST), agr and spa typing. From the 66 samples analyzed, 16 (24.2%) MRSA were detected. All strains were classified as multidrug-resistant as they were resistant to at least three classes of antibiotics. All isolates showed resistance to penicillin, erythromycin and clindamycin. Seven isolates were resistant to gentamicin and harbored the aac(6′)-Ie-aph (2″)-Ia gene. Resistance to tetracycline was detected in 10 isolates harboring the tet(K) gene. The IEC genes were detected in three isolates. MRSA strains belonged to CC97, CC1, CC5, CC15 or CC22. The isolates were assigned to six different spa types. In this study we found a moderate prevalence of multidrug-resistant MRSA strains in food-producing rabbits. This may represent concern for food safety and public health, since cross-contamination may occur, leading to the spread of MRSA and, eventually, the possibility of ingestion of contaminated meat. more...

Landmine clearance is an ongoing problem that currently affects millions of people around the world. This study evaluates the effectiveness of ground penetrating radar (GPR) in demining and unexploded ordnance detection using 2.3-GHz and 1-GHz high-frequency antennas. An automated detection tool based on machine learning techniques is also presented with the aim of automatically detecting underground explosive artifacts. A GPR survey was conducted on a designed scenario that included the most commonly buried items in historic battle fields, such as mines, projectiles and mortar grenades. The buried targets were identified using both frequencies, although the higher vertical resolution provided by the 2.3-GHz antenna allowed for better recognition of the reflection patterns. The targets were also detected automatically using machine learning techniques. Neural networks and logistic regression algorithms were shown to be able to discriminate between potential targets and clutter. The neural network had the most success, with accuracies ranging from 89% to 92% for the 1-GHz and 2.3-GHz antennas, respectively. more...

This work aimed to determine the frequency and diversity of Staphylococcus species carriage in horses intended for human consumption, as well as their resistance and virulence determinants. Eighty samples (30 nasal; 50 faecal) were recovered from 73 healthy horses in a Spanish slaughterhouse. The samples were cultured for staphylococci and methicillin-resistant staphylococci (MRS) recovery. The phenotype/genotype of antimicrobial resistance was analysed for all isolates. The spa-type and sequence-type (ST) were determined in Staphylococcus aureus strains; moreover, the presence of virulence and host-adaptation genes (tst, eta, etb, pvl, lukPQ, scn-eq, and scn) was studied by PCR. Staphylococcus species were detected in 27/30 (90%) and 33/50 (66%) of nasal and faecal samples, respectively. Ninety isolates belonging to eight species were recovered, with predominance of S. aureus (n = 34), Staphylococcus delphini (n = 19), and Staphylococcus sciuri (n = 19). S. aureus strains were all methicillin-susceptible (MSSA), 28/34 were susceptible to all the antibiotics tested, and the remaining six showed resistance to (gene-detected) streptomycin (ant (6)-Ia), penicillin (blaZ), and trimetroprim/sulphametoxazole (SXT) (dfrA, dfrG). The lineage ST1640/t2559 was predominant (n = 21). The genes lukPQ and scn-eq were present in all but the ST1640 isolates. Three S. sciuri isolates were multidrug-resistant. Healthy horses in Spain seem to be a reservoir for virulent MSSA and the lineage ST1640, although the presence of the latter in horses is described for the first time in this study. Moreover, the equine-adapted leukocidin gene lukPQ is frequent among S. aureus strains. A large variety of staphylococcal species with low antibiotic resistance rate were also observed. more...

El Curso de Especialista en Diagnóstico por Imágenes persigue un doble objetivo: pedagógico y también que los residentes obtengan el puntaje exigido para rendir el examen de especialista ante los organismos que correspondan. Hasta 2009, la manera tradicional del dictado de las clases en Bahía Blanca fue la presencial; a partir de ese año, se adoptó la modalidad de la televideoconferencia. Los programas fueron los habituales de videoconferencia, como el Skype u OoVoo, y sistemas de envío electrónicos tipo Rapidshare. Este sistema solo requiere de dos notebook, un proyector multimedia, un monitor extra y conexión a Internet de banda ancha. Una vez que el disertante envía la clase habitualmente en Power Point o Flash, se la instala en la notebook que se proyectará por el multimedio. La notebook restante, que posee cámara, se posiciona de manera que la proyección sea vista por el disertante. También puede dictarse la clase mediante la opción de"compartir la pantalla", pero esto tiene como dificultad que el ancho de banda no sea el adecuado, lo que lentifica la proyección. Durante la conferencia, el expositor se muestra en la pantalla de un monitor más grande y, al finalizar la exposición se da lugar a preguntas. Se realizaron conferencias múltiples, por ejemplo, entre Bahía Blanca, Tucumán y España, habiendo podido interactuar todos. Esta modalidad se está perfeccionando para que el año próximo se integren las residencias del país que quieran aprender en conjunto, sin limitación geográfica. También los Cursos Superiores de la Sociedad Argentina de Radiología son parte del proyecto. La experiencia pasada fue muy enriquecedora pues permitió escuchar a docentes de primer nivel, tanto nacionales como extranjeros, con el consecuente ahorro de tiempo y dinero.The Imaging Specialist Course has two goals, one being educational and the other focused on the possibility that residents will get the level required to take the specialist exam. Until the year 2009, students traditionally attended classes in Bahía Blanca. Thereafter, the video teleconferencing method was implemented. The programs were those commonly used for videoconferencing and included the Skype or Oovoo, and systems to electronically send data, such as Rapidshare. This system only consists of two electronic notebooks, a multimedia projection system, an additional monitor and remote connection through the Internet. The lecturer usually sends his/her presentation in Power Point or Flash. This is further downloaded in the notebook that will be used for multimedia projection. The other notebook, fitted with a camera, is placed in such a way that the lecturer will be able to watch the projection. The lecture may be also transmitted using the "shared screen" option. However, if the wide band is not adequate, projection will be slow. During his/her presentation, the lecturer is seen on the screen of a larger monitor, and is asked questions at the end of the lecture. Multiple videoconferencing was carried out between Bahía Blanca, Tucumán and Spain, with overall interaction. By next year, videoconferencing is expected to include those residencies around the country interested in shared learning without geographic boundaries. The Argentine Society of Radiology Courses are also part of this project. The preliminary experience was fruitful, since local and foreign highly qualified educators could be listened to, thus saving time and money. more...

This work focuses on radio wave propagation within forested environments, at 5.8 GHz. Concretely, we explore the advantages of implementing spatial diversity in reception or even in both ends for improving the strength of the received signal in such environments, which could be useful in applications such as vehicle-to-infrastructure, vehicle-to-vehicle, or emergency communications. Measurements gathered at both evergreen and deciduous forests sustain the thesis. Once processed, the results support the proposal of implementing a spatial diversity technique in reception or in both ends using a 2 × 4 (or 2 × 2) scheme in order to improve the connectivity at 5.8 GHz band within forests. In fact, we estimated a gain due to spatial diversity in reception of 5 dB and 2 dB at evergreen and deciduous forests, respectively, and 16 dB or 5 dB when implementing at both ends. more...

En este artículo se pretende dar un ejemplo práctico de cómo crear materiales multimedia (con el programa MALTED, del Ministerio de Educación español) para la enseñanza del español como segunda lengua en Educación Primaria. La continua llegada de inmigrantes a España, en la mayor parte de los casos de países en vías de desarrollo con hijos en edad escolar reclama la adopción de nuevas perspectivas a la hora de enseñar la lengua en el sistema educativo español. Debe enseñarse a los alumnos el manejo de las nuevas tecnologías, a la vez que se sigue un enfoque comunicativo al enseñar la lengua. Este proyecto fue desarrollado durante el curso 2010-2011 en la Universidad de Cantabria, Santander, España. This paper gives an example of how to create multimedia materials to teach Spanish as a Second Language in primary schools (using MALTED, software by the Spanish Ministry of Education). The continuous arrival of immigrants to Spain, mostly from undeveloped countries, demands new perspectives on teaching the language. It is necessary to teach these students how to use new technologies, and, at the same time teaching the language with a communicative approach. This project was developed during the course 2010-2011 at the University of Cantabria, Santander, Spain. more...

Se reseña el libro Mitos y realidades del desarrollo lingüístico en la escuela. Una fotografía de los libros de español del enfoque comunicativo.