Los virus entéricos como riesgos emergentes en la cadena alimentaria: el virus de la hepatitis E como ejemplo de la estrategia "una salud"

El autor dedica especial atención al virus de la hepatitits E, por ser de transmisión zoonótica y constituir un problema emergente. “Su transmisión alimentaria, -explica -, se demostró por primera vez en grupos de pacientes japoneses después de consumir carne cruda o poco cocida de cerdos salvajes o ciervos”. En Europa el virus ha sido detectado en productos de carne de cerdo en varios países, además de otros alimentos “como mejillones, mariscos y otros bivalvos, y más recientemente en productos frescos como lechuga y frambuesas, así como leche de vaca y cabra”. La infección se puede contraer a través de productos cárnicos producidos localmente, y señala expresamente la carne de caza y de cerdo procesada. El elevado impacto asistencial y económico asociado al carácter emergente de los virus entéricos ha provocado que, “tanto científicos como instituciones en Salud Pública centren sus esfuerzos en su detección y control”, aunque los datos pueden estar subestimados por la ausencia de métodos que hagan posible conocer con exactitud su incidencia en las diferentes etapas de la cadena de producción alimentaria, y “en especial aquella que se dedica a la transformación de productos de origen animal”. Por ese motivo se muestra partidario de “calibrar los procedimientos actuales de desinfección en la industria alimentaria para poder establecer de una manera fehaciente una evaluación cuantitativa del riesgo vírico en los alimentos”. Concluye con un llamamiento a la aplicación de la estrategia ‘una salud’, que se articule en torno a tres pilares, “el control en la producción primaria (sanidad animal), en la comunidad (sanidad humana) y en el medio ambiente (sanidad ambiental)”, y en la que defendió que “el papel del veterinario ha de ser esencial”

A survey of Mycoplasma agalactiae in dairy sheep farms in Spain

BACKGROUND: Contagious Agalactia (CA) is one of the major animal health problems in small ruminants because of its economic significance. Currently, four Mycoplasma spp. have been associated with this syndrome: M. agalactiae, M. mycoides subsp. capri, M. capricolum subsp. capricolum and M. putrefaciens. Their presence has been evaluated in several studies conducted in CA-endemic countries. However, previous Spanish studies have been focused on caprine CA, and there is a knowledge gap regarding which Mycoplasma species are present in sheep flocks from Spain, which has the second highest number of sheep amongst the 27 European Union member states. Consequently, we investigated the presence and geographic distribution of the four CA-causing mycoplasmas in Spanish dairy sheep farms. This is the first time such an investigation has been performed. RESULTS: Three hundred thirty nine out of 922 sheep flocks were positive for M. agalactiae by real time PCR (36.8%) and 85 by microbiological identification (9.2%). Interestingly, all 597 milk samples assessed for the presence of M. mycoides subsp. capri, M. capricolum subsp. capricolum and M. putrefaciens tested negative. To evaluate the intermittent excretion of the pathogen in milk, we sampled 391 additional farms from 2 to 5 times, resulting that in 26.3% of the cases a previously positive farm tested negative in a later sampling. CONCLUSIONS: M. agalactiae was the only Mycoplasma species detected in the study area showing a high frequency of presence and wide distribution. Therefore, the establishment of a permanent surveillance network is advantageous, as well as the implementation of control and prevention measures to hinder the dissemination of M. agalactiae and to prevent the entrance of other Mycoplasma species

Molecular epidemiology of methicillin-resistant Staphylococcus aureus in a university hospital in northwestern Spain

Continuous monitoring of methicillin-resistant Staphylococcus aureus (MRSA) is necessary to understand the clonal evolution of successful lineages. In this study, we identifi ed the MRSA clones circulating in a Spanish hospital during a 2-year period, assessed their relationship with antimicrobial resistance profi les, and investigated the presence of the emerging community-associated and livestock-associated MRSA lineages (CA-MRSA, LA-MRSA). CC5-MRSA-IV isolates were the most frequently recovered, which supports the previously reported prevalence of this clone in Spanish hospitals. We observed ST125 isolates that harbored specifi c cassette chromosome recombinase (ccr) gene elements of the staphylococcal cassette chromosome mec (SCCmec) types IV and VI. That clone, which was fi rst detected only recently, has increased resistance to erythromycin. Furthermore, 94% of the infections were caused by non-multiresistant isolates. Neither CA-MRSA nor LA-MRSA isolates were observed. These fi ndings, along with related events over the last decade, suggest the establishment of a clonal endemic population in the Spanish clinical environment. [Int Microbiol 2014; 17(3):149-157]Keywords: methicillin-resistant Staphylococcus aureus (MRSA) · clonal population · molecular epidemiology · multilocus sequence typin

Utilización y utilidad de los indicadores ambientales principales de sustentabilidad forestal

A partir de un estudio empírico sobre la determinación, obtención, utilización y evolución de una serie de indicadores ambientales principales para los bosques y cultivos forestales en Asturias (durante el período 1975-2000), se pretende justificar la utilidad de dichos indicadores como aproximación a la medición de la vertiente ambiental de la sustentabilidad forestal

Modelling the fate and serogroup variability of persistent Listeria monocytogenes strains on grated cheese at different storage temperatures

Processed cheese from cow's milk is one of the most consumed dairy products worldwide. Since this product is defined as ready-to-eat, foodborne pathogens such as Listeria monocytogenes can represent a health concern for susceptible populations. In this study, the individual and combined kinetic behaviour of four L. monocytogenes serogroups (namely, 1/2a, 1/2b, 1/2c and 4b) persistently isolated from a Spanish cheesemaking factory was modelled on grated cheese at different isothermal conditions (4 and 12 °C) during a 120-days period. The serogroup variability was characterized over the storage time by the isolation and identification of the different serogroups in the cocktail containing the four strains. This processed cheese did not support the growth of L. monocytogenes during storage. Survival patterns described by the log-linear type model indicated a high variability of L. monocytogenes serotypes at the tested temperatures: L. monocytogenes serogroup 4b showed a more rapid decrease rate at 4 °C than at 12 °C, while the opposite trend was found for the rest of serogroups and the L. monocytogenes cocktail containing all the strains. Survival rate of L. monocytogenes serogroup 1/2c at 4 °C was 0.007 log CFU/d being the most resistant serotype while at 12 °C, serogroup 1/2a showed the lowest survival rate (0.011 log CFU/d), thus showing a prolonged survival at this temperature. This study highlights the potential implications of L. monocytogenes contamination in processed cheese and shows that serogroup variability should be considered when evaluating survival patterns in contaminated products. Finally, the predictive models developed here could be useful to assist food operators to set specific storage conditions and formulations to avoid L. monocytogenes growth and survival in grated cheeses.European Union (EU) funded Integrated Project PROMISE (project number 265877; 7th Framework Programme

Zero-inflated binomial regressions for modelling low prevalence of pathogens in chicken meat as affected by sampling site

Contamination of raw poultry meat with foodborne pathogens could occur because of improper handling at primary production and slaughterhouse levels. Low microbial prevalence data often consists of a high amount of non-detections (zero positives), so a flexible framework is required to characterise the underlying microbial distribution and conduct reliable inferential statistics. Thus, the objective of this work was to evaluate the performance of zero-inflated binomial (ZIB) regression models to describe the effects of sampling site (carcass, thigh, breast, wings) on the measured incidences of Salmonella, Listeria monocytogenes and Staphylococcus aureus on chicken meat. For each pathogen, four regression models based on the zero-inflated binomial ZIB (p, w0) distribution were fitted to the presence/absence data with sampling site as covariate and random-effects due to sampling occasion either in the binomial probability(p)or in the extra-proportion of non-detections(w0).Forthe three pathogens, the sampling site exerted a greater effect on w0 than on p itself, with breast bearing the lowest prevalence estimatesofSalmonellaspp.(mean: 0.88%;95%CI:0.02–1.95%)andS.aureus(mean1.48%;95%CI: 0.01–4.00%). The fitting capacity of the models was further improved when random effects due to sampling occasion were placed in w0 (deviances decreased from 146.7–156.7 to 140.2–140.6). This would imply that, theoretically, the variability in pathogens’ occurrence from batch to batch mainly arises from the variability in non-contaminated zones. At any sampling site, the mean prevalence was estimated as 1.35 (95% CI: 0.15 – 2.70) for Salmonella, 2.11 (95% CI: 0.04 – 5.63) for L. monocytogenes and 2.36 (95% CI: 0.04 – 5.12) for S. aureus. Sampling performance analysis showed that wings were mostly suitable to detect Salmonella and S. aureus with higher probability (0.016 and 0.035 respectively), while for L. monocytogenes, sampling of thigh could be more effective (0.032).Dr. Gonzales-Barron wishes to acknowledge the financial support provided by the Portuguese Foundation for Science and Technology (FCT) through the award of a five-year Investigator Fellowship (IF) in the mode of Development Grants ( IF/00570 )info:eu-repo/semantics/publishedVersio

Design and Evaluation of a RISC-V based SoC for Satellite on-board Networking

Ponencia presentada en XXXVIII Conference on Design of Circuits and Integrated Systems - DCIS 2023, November 15-17, 2023, Málaga, Spain.SpaceWire is a communication protocol that has become widely used in spacecraft for connecting instruments to data processors, mass-memory, and control processors. Field-Programmable Gate Arrays (FPGAs) have been a popular choice for implementing SpaceWire nodes due to their flexibility to meet unique requirements of each program or product. This paper presents a comparative study of two implementations of SpaceWire nodes, based on two different FPGA technologies, AMD-Xilinx SRAM-based and Microchip (Microsemi) FLASH based. The study compares the resource requirements and estimated power consumption of both implementations, using the same HDL SpaceWire IP core, with the SRAM-based one incorporating a 32-bit Microblaze soft-CPU, and the FLASH based one using a 32-bit RISC-V CPU. The obtained results are compared, and the paper concludes that FLASH-based FPGAs are more suitable for applications that require high reliability, tamper resistance, and fast, reliable restarts. In contrast, SRAM-based FPGAs are preferred in applications that require high performance and reconfigurability. The study shows that both FPGA technologies are capable of implementing SpaceWire nodes effectively and efficiently, and designers can choose the technology that best suits the specific requirements of each project.This work has been supported, within the fund for research groups of the Basque university system IT1440-22, by the Department of Education and, within SOC4CRIS KK-2023/00015 and COMMUTE ZE-2021/00931 projects, by the Elkartek and Hazitek programs, both of the Basque Government; the latter also by the Ministerio de Ciencia e Innovación of Spain through the Centro para el Desarrollo Tecnológico Industrial (CDTI) within the project IDI-20220543, and through the Fondo Europeo de Desarrollo Regional 2014-2020 (FEDER funds)

Bacteriophages as Biotechnological Tools

Bacteriophages are ubiquitous organisms that can be specific to one or multiple strains of hosts, in addition to being the most abundant entities on the planet. It is estimated that they exceed ten times the total number of bacteria. They are classified as temperate, which means that phages can integrate their genome into the host genome, originating a prophage that replicates with the host cell and may confer immunity against infection by the same type of phage; and lytics, those with greater biotechnological interest and are viruses that lyse the host cell at the end of its reproductive cycle. When lysogenic, they are capable of disseminating bacterial antibiotic resistance genes through horizontal gene transfer. When professionally lytic—that is, obligately lytic and not recently descended from a temperate ancestor—they become allies in bacterial control in ecological imbalance scenarios; these viruses have a biofilm-reducing capacity. Phage therapy has also been advocated by the scientific community, given the uniqueness of issues related to the control of microorganisms and biofilm production when compared to other commonly used techniques. The advantages of using bacteriophages appear as a viable and promising alternative. This review will provide updates on the landscape of phage applications for the biocontrol of pathogens in industrial settings and healthcare.This study was funded by CNPQ and the Federal University of Santa Catarina, SIGPEX UFSC–201917940

Structural, dynamic, and electronic properties of liquid tin: An ab initio molecular dynamics study

Producción CientíficaWe report on a study of several structural, dynamic, and electronic properties of liquid Sn at a thermodynamic state close to the triple point (573 K) and another one at a higher temperature (1273 K). This study has been performed by ab initio molecular dynamics simulations using 205 atoms and around 20 ps of simulation time. The calculated static structures show a good agreement with the available experimental data. The dynamic structure factors fairly agree with their experimental counterparts obtained by inelastic x-ray scattering experiments, which display inelastic side peaks. The calculated dispersion relations exhibit a positive dispersion, although not so marked as suggested by the experiment; moreover, its slope at the long-wavelength limit compares favorably with the experimental sound velocity. Electron densities near selected triplets of atoms are similar to those appearing in the solid phases, but these features have an extremely short lifetime, so they should not be considered as solid remnants in the melt