Impact of a nanofiltration system on microplastic contamination in Geneva groundwater (Switzerland).

Microplastics (MPs) have been observed in the oceans, fresh waters, karstic water and remote water bodies. However, little is known on groundwater contamination, which is a natural resource of utmost importance for millions of people and is often perceived as a reliable source of water. Moreover, nanofiltration is perceived as a reliable technology to remove contaminants from water. In this study, large sample volumes of a silty-sandy gravel aquifer and the corresponding nanofiltered water were analysed for the presence of MPs (> 20 µm) using Fourier transform infrared (FTIR) microscopy. Concentration in ground water was 8 ± 7 MPs/m3 and increased to 36 ± 11 MPs/m3 in nanofiltered water. All MPs had a maximum Ferret diameter lower than 500 µm. Size distribution of MPs was towards the small size class (20-50 µm). In groundwater, 33% of MPs were detected in the smallest size class (20-50 µm) and 67% in the 50-100-µm-size class. In comparison, around 52% of MPs in nanofiltered water were observed in the 20-50 µm size class. Moreover, 33% of the MPs observed in nanofiltered water were in the 50-100 µm size class and 15% in the 100-500-µm-size class. From a chemical point of view, different plastic polymers were identified in groundwater and in nanofiltered water, such as polypropylene (PP), polyvinyl chloride (PVC), ethylene (vinyl acetate) copolymer (EVA), polyethylene (PE), polyethylene terephthalate (PET), polymethyl methacrylate (PMMA) and other polymer materials (such as polystyrene-based copolymers, vinyl-based copolymers). Fibres were observed in all samples, but only a small number of fibres (near 1%) were identified as PP synthetic fibres in nanofiltered water. Furthermore, no clear difference of fibre concentrations was observed between groundwater (232 ± 127 fibres/m3) and nanofiltered water (247 ± 118 fibres/m3). Groundwater had extremely low levels of microplastics, and although the nanofiltration effectively removes suspended particulate matter, it slightly contaminates the filtered water with MPs.

To cheat or not to cheat: cheatable and non-cheatable virulence factors in Pseudomonas aeruginosa.

Important bacterial pathogens such as Pseudomonas aeruginosa produce several exoproducts such as siderophores, degradative enzymes, biosurfactants, and exopolysaccharides that are used extracellularly, benefiting all members of the population, hence being public goods. Since the production of public goods is a cooperative trait, it is in principle susceptible to cheating by individuals in the population who do not invest in their production, but use their benefits, hence increasing their fitness at the expense of the cooperators' fitness. Among the most studied virulence factors susceptible to cheating are siderophores and exoproteases, with several studies in vitro and some in animal infection models. In addition to these two well-known examples, cheating with other virulence factors such as exopolysaccharides, biosurfactants, eDNA production, secretion systems, and biofilm formation has also been studied. In this review, we discuss the evidence of the susceptibility of each of those virulence factors to cheating, as well as the mechanisms that counteract this behavior and the possible consequences for bacterial virulence.

Contamination and removal efficiency of microplastics and synthetic fibres in a conventional drinking water treatment plant in Geneva, Switzerland.

Although it is known that freshwater resources are contaminated with microplastics (MPs), still limited information is known about the efficiency of large drinking water treatment plants (DWTP) to remove microplastics. Moreover, reported concentrations of MPs in drinking water variates from some units to thousands of units per litre and the sampling volumes used for MPs analysis are generally heterogeneous and limited. The present study evaluates the removal of MPs and synthetic fibres in the main DWTP of Geneva, Switzerland, by considering large sampling volumes at different time intervals. Furthermore, contrary to other studies, this DWTP does not count with a clarification process before sand filtration and coagulated water is sent directly to sand filtration. In this study a distinction is made between microplastics as fragments, films, pellets, and synthetic fibres. Raw water and effluents of each filtering mass (sand and activated carbon filtration) are analysed for the presence of MPs and synthetic fibres with sizes ≥63 µm using infrared spectroscopy. Concentrations of MPs in raw water range from 25.7 to 55.6 MPs/m3 and in treated water from 0 to 4 MPs/m3, respectively. Results show that 70 % of MPs are retained during sand filtration and total removal is equal to 97 % in treated water after activated carbon filtration. Concentration of identified synthetic fibres is low (average value of 2 synthetic fibres/m3) and constant in all steps of water treatment. Chemical composition of microplastics and synthetic fibres is found more heterogeneous in raw water than after sand filtration and activated carbon filtration, indicating the persistence of some types of plastics (like polyethylene and polyethylene terephthalate) in water treatment processes. Heterogeneities in MP concentrations are observed from one sampling campaign to another, indicating significant variations of MP concentrations in raw water.

Assessment of indoor air quality and risk of COVID-19 infection in Spanish secondary school and university classrooms.

Despite the risk of transmission of SARS-CoV-2, Spanish educational centers were reopened after six months of lockdown. Ventilation was mostly adopted as a preventive measure to reduce the transmission risk of the virus. However, it could also affect indoor air quality (IAQ). Therefore, here we evaluate the ventilation conditions, COVID-19 risk, and IAQ in secondary school and university classrooms in Toledo (central Spain) from November 2020 to June 2021. Ventilation was examined by monitoring outdoor and indoor CO2 levels. CO2, occupancy and hygrothermal parameters, allowed estimating the relative transmission risk of SARS-CoV-2 (Alpha and Omicron BA.1), H r, under different scenarios, using the web app COVID Risk airborne . Additionally, the effect of ventilation on IAQ was evaluated by measuring indoor/outdoor (I/O) concentration ratios of O3, NO2, and suspended particulate matter (PM). University classrooms, particularly the mechanically ventilated one, presented better ventilation conditions than the secondary school classrooms, as well as better thermal comfort conditions. The estimated H r for COVID-19 ranged from intermediate (with surgical masks) to high (no masks, teacher infected). IAQ was generally good in all classrooms, particularly at the university ones, with I/O below unity, implying an outdoor origin of gaseous pollutants, while the source of PM was heterogeneous. Consequently, controlled mechanical ventilation systems are essential in educational spaces, as well as wearing well-fitting FFP2-N95 masks indoors is also highly recommended to minimize the transmission risk of COVID-19 and other airborne infectious diseases.

Modifying rainfall patterns in a Mediterranean shrubland: system design, plant responses, and experimental burning.

Global warming is projected to increase the frequency and intensity of droughts in the Mediterranean region, as well as the occurrence of large fires. Understanding the interactions between drought, fire and plant responses is therefore important. In this study, we present an experiment in which rainfall patterns were modified to simulate various levels of drought in a Mediterranean shrubland of central Spain dominated by Cistus ladanifer, Erica arborea and Phillyrea angustifolia. A system composed of automatic rainout shelters with an irrigation facility was used. It was designed to be applied in vegetation 2 m tall, treat relatively large areas (36 m2), and be quickly dismantled to perform experimental burning and reassembled back again. Twenty plots were subjected to four rainfall treatments from early spring: natural rainfall, long-term average rainfall (2 months drought), moderate drought (25% reduction from long-term rainfall, 5 months drought) and severe drought (45% reduction, 7 months drought). The plots were burned in late summer, without interfering with rainfall manipulations. Results indicated that rainfall manipulations caused differences in soil moisture among treatments, leading to reduced water availability and growth of C. ladanifer and E. arborea in the drought treatments. However, P. angustifolia was not affected by the manipulations. Rainout shelters had a negligible impact on plot microenvironment. Experimental burns were of high fire intensity, without differences among treatments. Our system provides a tool to study the combined effects of drought and fire on vegetation, which is important to assess the threats posed by climate change in Mediterranean environments.

El proceso de absorción del Real Tribunal del Protoalbeitarato por la Escuela de Veterinaria de Madrid (1792-1855) / The takeover process of the Real Tribunal del Protoalbeitarato by the Faculty of Veterinary of Madrid (1792-1855)

La absorción del Real Tribunal del Protoalbeitarato1 por la Escuela de Veterinaria de Madrid presenta ciertas singularidades respecto al proceso equivalente en medicina y farmacia. La pugna y hegemonía del Real Tribunal durante casi sesenta años desde la creación de la Escuela de Veterinaria (1792), ha sido estudiada por la historiografía tradicional con una visión centrada fundamentalmente en aspectos veterinarios. En el presente artículo se investigan en detalle los procesos conducentes a la absorción y se pone de manifiesto la relevancia de las motivaciones políticas y su predominio sobre las de carácter técnico, sanitario o profesional. Por ello, se analiza el juego de instituciones y de agentes externos a la veterinaria implicados, en especial destacamos el papel desempeñado por el XV Marqués de Cerralbo (AU)

The absorption of the Real Tribunal del Protoalbeitarato by the Veterinary Science School of Madrid shows several singularities in relation to the equivalent process in medicine and pharmacy.The conflict and the hegemony of the Real Tribunal during almost sixty years from the creation of the Veterinary Science School (1792), has been studied by the traditional historiography with a view fundamentally focused on veterinary aspects. In this article, the process of absorption is investigated in full detail. Also, the relevance of political motivations and their predominance over technical, sanitary or professional motivations are shown. So, the game of institutions and agents which are external to the veterinary science are analysed; specially, the out standing role performed by the XV Marquis of Cerralbo(AU)

Valor diagnóstico de la gammagrafía de perfusión miocárdica con 99mTc-Tetrofosmina en mujeres previamente revascularizadas / Diagnostic value of myocardial perfusion imaging with 99mTc-tetrofosmin in a population of women previously revascularized

Fundamento y objetivo: Se trata de un estudio transversal donde se han determinado los valores de sensibilidad y especificidad del estudio de perfusión miocárdica con 99mTc-Tetrofosmina en protocolo de un día tras estímulo farmacológico con dipiridamol, en una población de mujeres previamente revascularizadas, así como la relación con los territorios vasculares coronarios, tomando como referencia la coronariografía. Pacientes: Se han estudiado con carácter retrospectivo 53 historias clínicas de mujeres sometidas a una prueba de perfusión miocárdica y a una coronariografía de control. Resultados: Los valores de sensibilidad y especificidad para la población fueron de 64,29 por ciento y 75,0 por ciento respectivamente. Por territorio arterial coronario, los valores de sensibilidad y especificidad para la arteria DA fueron de 68,75 por ciento y 75,0 por ciento respectivamente, para la Cx de 37,93 por ciento y 88,89 por ciento, y para la CD de 46,43 por ciento y 60,71 por ciento. Conclusiones: En las mujeres que han sido previamente revascularizadas, la gammagrafía de perfusión miocárdica con 99mTc-Tetrofosmina y dipiridamol en protocolo de un día parece ser una prueba idónea para realizar el seguimiento de pacientes.

Background: This is a cross-sectional study to identify the values of sensitivity and specificity of myocardial perfusion imaging with 99mTc-tetrofosmin one-day protocol after pharmacological stimulation with dipyridamole in a population of women previously revascularized and the relationship of findings to coronary vascular territories, with coronary angiography as a gold standard. Patients We studied retrospectively 53 medical records of women undergoing myocardial perfusion test and control coronary angiography. Results: The sensitivity and specificity for the population were 64.29 percent and 75.0 percent respectively. For coronary artery territory, the values of sensitivity and specificity for the LAD were 68.75 percent and 75.0 percent respectively, for Cx of 37.93 percent and 88.89 percent, and for the RCA 46.43 percent and 60.71 percent. Conclusions: In women who have been previously revascularized, myocardial perfusion scintigraphy with 99mTc-tetrofosmin and dipyridamole in one-day protocol seems to be a suitable test to monitor patients.

[The takeover process of the "Real Tribunal del Protoalbeitarato" by the faculty of Veterinary of Madrid (1792-1855)]. / El proceso de absorción del Real Tribunal del Protoalbeitarato por la Escuela de Veterinaria de Madrid (1792-1855).

The absorption of the "Real Tribunal del Protoalbeitarato" by the Veterinary Science School of Madrid shows several singularities in relation to the equivalent process in medicine and pharmacy. The conflict and the hegemony of the "Real Tribunal" during almost sixty years from the creation of the Veterinary Science School (1792), has been studied by the traditional historiography with a view fundamentally focused on veterinary aspects. In this article, the process of absorption is investigated in full detail. Also, the relevance of political motivations and their predominance over technical, sanitary or professional motivations are shown. So, the game of institutions and agents which are external to the veterinary science are analysed; specially, the outstanding role performed by the XV Marquis of Cerralbo.

PKA-mediated Golgi remodeling during cAMP signal transmission.

Cyclic AMP (cAMP)-dependent protein kinase A (PKA) is part of the set of signaling proteins that are stably associated to the cytosolic surface of Golgi membranes in mammalian cells. In principle, Golgi-associated PKA could participate in either signal transduction events and/or the coordination of Golgi transport activities. Here, we show data indicating that although Golgi-associated PKA is activated fast and efficiently during cell stimulation by an extracellular ligand it does not contribute significantly to cAMP signal transmission to the nucleus. Instead, most of the PKA catalytic subunits Calphaderived from the Golgi complex remain localized in the perinuclear cytoplasm where they induce changes in Golgi structural organization. Thus, in stimulated cells the Golgi complex appears collapsed, showing increased colocalization of previously segregated markers and exhibiting merging of different proximal cisternae within a single stack. In contrast, the trans-Golgi network remains as a separate compartment. Consequently, the rate of protein transport is increased whereas glycan processing is not severely affected. This remodeling process requires the presence of PKA activity associated to the Golgi membranes. Together these data indicate that Golgi-associated PKA activity is involved in the adaptation of Golgi dynamic organization to extracellular signaling events.

Golgi structural stability and biogenesis depend on associated PKA activity.

The mammalian Golgi complex consists of stacks of cisternae linked laterally into a continuous perinuclear ribbon structure. Protein kinase A is stably associated with the Golgi complex during interphase. To analyze its role in Golgi structural maintenance cells were depleted of protein kinase A regulatory subunits using small interfering RNAs. Under these conditions, the catalytic subunits redistributed to the cytosol and the entire Golgi complex underwent disassembly into multiple juxtanuclear fragments. A similar effect took place following pharmacological inhibition or redistribution of the complete holoenzyme to the cytosol. Golgi fragments maintained their polarization and competence for anterograde protein trafficking. By electron microscopy, they were identified as whorl-like structures composed of concentrically arrayed cisternae. To test a possible role of protein kinase A in Golgi biogenesis we analyzed its involvement during Golgi reassembly from the endoplasmic reticulum. In cells incubated with protein kinase A inhibitors, Golgi reconstruction was arrested at a late step of the reassembly process. This is consistent with the stage of enzyme recruitment from cytosol to emerging Golgi membranes during the reassembly process. We conclude that protein kinase A activity plays a relevant role in the assembly and maintenance of a continuous Golgi ribbon from separated membrane stacks.

The retrieval function of the KDEL receptor requires PKA phosphorylation of its C-terminus.

The KDEL receptor is a Golgi/intermediate compartment-located integral membrane protein that carries out the retrieval of escaped ER proteins bearing a C-terminal KDEL sequence. This occurs throughout retrograde traffic mediated by COPI-coated transport carriers. The role of the C-terminal cytoplasmic domain of the KDEL receptor in this process has been investigated. Deletion of this domain did not affect receptor subcellular localization although cells expressing this truncated form of the receptor failed to retain KDEL ligands intracellularly. Permeabilized cells incubated with ATP and GTP exhibited tubular processes-mediated redistribution from the Golgi area to the ER of the wild-type receptor, whereas the truncated form lacking the C-terminal domain remained concentrated in the Golgi. As revealed with a peptide-binding assay, this domain did not interact with both coatomer and ARF-GAP unless serine 209 was mutated to aspartic acid. In contrast, alanine replacement of serine 209 inhibited coatomer/ARF-GAP recruitment, receptor redistribution into the ER, and intracellular retention of KDEL ligands. Serine 209 was phosphorylated by both cytosolic and recombinant protein kinase A (PKA) catalytic subunit. Inhibition of endogenous PKA activity with H89 blocked Golgi-ER transport of the native receptor but did not affect redistribution to the ER of a mutated form bearing aspartic acid at position 209. We conclude that PKA phosphorylation of serine 209 is required for the retrograde transport of the KDEL receptor from the Golgi complex to the ER from which the retrieval of proteins bearing the KDEL signal depends.