Additive manufacturing of wet-spun chitosan/hyaluronic acid scaffolds for biomedical applications.

Additive manufacturing (AM) holds great potential for processing natural polymer hydrogels into 3D scaffolds exploitable for tissue engineering and in vitro tissue modelling. The aim of this research activity was to assess the suitability of computer-aided wet-spinning (CAWS) for AM of hyaluronic acid (HA)/chitosan (Cs) polyelectrolyte complex (PEC) hydrogels. A post-printing treatment based on HA chemical cross-linking via transesterification with poly(methyl vinyl ether-alt-maleic acid) (PMVEMA) was investigated to enhance the structural stability of the developed scaffolds in physiological conditions. PEC formation and the esterification reaction were investigated by infrared spectroscopy, thermogravimetric analysis, evolved gas analysis-mass spectrometry, and differential scanning calorimetry measurements. In addition, variation of PMVEMA concentration in the cross-linking medium was demonstrated to strongly influence scaffold water uptake and its stability in phosphate buffer saline at 37 °C. The in vitro cytocompatibility of the developed hydrogels was demonstrated by employing the murine embryo fibroblast Balb/3T3 clone A31 cell line, highlighting that PMVEMA cross-linking improved scaffold cell colonization. The results achieved demonstrated that the developed hydrogels represent suitable 3D scaffolds for long term cell culture experiments.

Miositis aguda asociada a infección por virus influenza. Serie de casos en un hospital pediátrico

La miositis aguda benigna asociada a influenza es una complicación esporádica. En Argentina, en el año 2022, hubo un aumento temprano de la circulación de influenza y del número total de las notificaciones, con la aparición de miositis secundarias. Serie clínica retrospectiva de nueve pacientes pediátricos que consultaron por dolor e impotencia funcional de extremidades inferiores, y enzimas musculares elevadas, en el hospital Pedro de Elizalde de la Ciudad Autónoma de Buenos Aires, entre agosto y octubre del 2022. En todos se detectó infección por virus influenza y se recuperaron sin secuelas. La miositis aguda benigna es una entidad infrecuente en la infancia, cuyo diagnóstico es predominantemente clínico y de recuperación ad integrum. Debe ser sospechada en pacientes con clínica compatible en contexto de alta circulación viral. La vigilancia epidemiológica aporta herramientas para identificar los virus circulantes y sus posibles complicaciones.

Benign acute myositis associated with influenza is a sporadic complication. In Argentina, in 2022, there was an early increase in influenza circulation and the total number of notifications, with the appearance of secondary myositis. Retrospective clinical series of nine pediatric patients who consulted for pain and functional impotence of the lower extremities, and elevated muscle enzymes, at the Pedro de Elizalde hospital in the Autonomous City of Buenos Aires, between August and October 2022. In all of them, infection by influenza virus and recovered without sequelae. Benign acute myositis is a rare entity in childhood, whose diagnosis is predominantly clinical and recovery ad integrum. It should be suspected in patients with compatible symptoms in a context of high viral circulation. Epidemiological surveillance provides tools to identify circulating viruses and their possible complications.

Determination of perfluoroalkyl acids in different tissues of graminaceous plants.

A method for the determination of 12 perfluoroalkyl acids (PFAA) in vegetal samples was proposed. The analytical procedure was developed to optimize the detection of short-chain PFAA (C < 8) due to their higher potential to be translocated and bioaccumulated in plants than long-chain congeners. The method, based on ultrasonic extraction, clean-up and HPLC-MS/MS analysis, determined PFAA in different plant tissues allowing the PFAA distribution and partition in vegetal compartments to be studied. The performance of this analytical procedure was validated by analysing samples (root, stem and leaf) of reed grass. The validated method was then applied to graminaceous plants from an agricultural area impacted by a fluorochemical plant discharge (Northern Italy). The PFAA congeners were detected in most of the samples with ΣPFAA concentrations in the whole plant ranging from

Exposure assessment of PFAS-contaminated sites using avian eggs as a biomonitoring tool: A frame of reference and a case study in the Po River valley (Northern Italy).

For many years, eggs of diverse bird species have been used as monitoring tools in studies investigating perfluoroalkyl substances (PFAS) contamination, especially in marine and remote areas. Avian eggs are a suitable monitoring matrix because they are relatively easy to collect and their yolks store diverse maternally transferred PFAS. Moreover, the concentrations of PFAS detected in the eggs are a good proxy for maternal exposure and allow the assessment of the potential risk for birds. These features support the use of avian eggs as a key monitoring tool in exposure assessment of PFAS-contaminated sites. We first review the recent application of avian eggs in PFAS monitoring in environmental risk assessment schemes, highlighting strengths and limitations and suggesting which criteria should be considered when selecting a proper study species and structuring the sampling and analytical protocol. Eventually, we report findings from a field study realized in 2020 near a perfluoropolymer factory site in the upper Po plain (Northern Italy), revealing an unprecedented contamination level of PFOA and C6O4 in three species of wild passerines. In future, long-term monitoring of PFAS contamination using avian eggs should be maintained, to provide crucial information on the temporal trend of fluorochemical production and waste disposal, while facilitating early identification of emerging PFAS as well as the quantification of their biomagnification across the trophic web. Integr Environ Assess Manag 2021;17:733-745. © 2021 SETAC.

Per- and Polyfluoroalkyl Substances (PFAS) in Fish from European Lakes: Current Contamination Status, Sources, and Perspectives for Monitoring.

Concentrations in fish of per- and polyfluoroalkyl substances (PFAS) were reported for 7 deep lakes in the European subalpine area: Lakes Geneva, Lugano, Maggiore, Iseo, Como, Garda, and Mergozzo; one shallow lowland lake (Varese); and 2 high-altitude alpine lakes (>2000 m a.s.l). Fillets and, in selected cases, other body fractions (viscera, liver, and residual carcass) from 8 fish species were analyzed. The possibility of harmonizing the monitoring protocols was tested. Results suggest that the sampling season is not critical for PFASs and the total protein content cannot be used for normalization of tissue concentrations because PFASs bind to specific proteins. Moreover, the polar lipid content could be used to reduce the variability of PFAS concentrations in phospholipid rich fractions of fish such as viscera and carcass. The data comparison and analysis show that the PFAS contamination in lake fish is generally correlated with the degree of urbanization of the lake catchment; however, it is sometimes difficult to compare absolute concentrations in lake fish because the lake hydro-morphological characteristics play a substantial role in determining the chemical concentrations of persistent and mobile contaminants. Environ Toxicol Chem 2021;40:658-676. © 2020 SETAC.

Uptake and translocation of perfluoroalkyl acids (PFAAs) in hydroponically grown red chicory (Cichorium intybus L.): Growth and developmental toxicity, comparison with growth in soil and bioavailability implications.

Short-chain perfluoroalkyl acids (PFAAs) have shown a high potential for plant (crop) uptake, making them possibly significant contributors to the total dietary exposure to PFAAs. The plant uptake of PFAAs is a complex process that needs better characterization, as it does not only depend on perfluoroalkyl chain length, but also on their polar terminal group, on the plant species and the exposure media. Here, a plant uptake study with nine perfluoroalkyl acids (PFAAs) was carried out under the hydroponic (soilless) exposure conditions. Red chicory was grown in a nutrient solution, spiked with PFAAs mixture at three different concentrations (i.e. 62.5, 125 and 250 µg/L), in order to extend the range of levels tested and reported in the literature so far. Bioaccumulation metrics and transpiration stream concentration factors (TSCFs) were employed for the plant uptake characterization and consequent comparison with the results of soil uptake experiment we previously performed with the same crop. The results showed that calculated root concentration factors (RCFs) increase with PFAA chain length, while the opposite chain length dependence was present for shoots. Plants from two treatments with the highest PFAAs concentrations manifested physiological changes (discoloration, inhibited roots and leaves growth), despite of the used exposure concentrations being much lower than previously published phytotoxicity thresholds. A comparison among RCFs and TSCFs derived from hydroponic and from the soil experiment has emphasized their different magnitudes and PFAAs chain length dependence patterns. They could not be ascribed only to soil sorption as a process decreasing PFAAs bioavailability for plants, but also to developmental differences between the root systems formed in soil and in nutrient solution and to the potential competitive PFAAs sorption to roots in hydroponics. The interchangeable use of bioaccumulation and translocation parameters derived in hydroponic and soil systems would lead to erroneous conclusions and plant uptake predictions.

Uptake and translocation of perfluoroalkyl acids (PFAA) in red chicory (Cichorium intybus L.) under various treatments with pre-contaminated soil and irrigation water.

Perfluoroalkyl acids (PFAAs), particularly short-chained ones, have high potential for crop uptake, posing a threat to human health in contaminated areas. There is a scarcity of studies using contaminated water as the medium for PFAAs delivery to crops, and a lack of data on the partitioning of PFAA mixtures in growing media. In this context, a controlled experimental study was carried out in a greenhouse to investigate the uptake of a PFAA mixture into red chicory, a typical crop from a major PFAA contamination hot-spot in northern Italy, under treatments with environmentally relevant concentrations in spiked irrigation water and soil, separately and simultaneously. To our knowledge, this is the first study involving multiple exposure media and laboratory adsorption/desorption batch tests as a way of assessing the decrease in the bioavailability of PFAAs from soil. Exposure concentrations for each of the 9 utilized PFAAs were 0, 1, 10 and 80 µg/L in irrigation water and 0, 100 and 200 ng/gdw in soil, combined into 12 treatments. The highest bioaccumulation was measured for PFBA in roots (maximum of 43 µg/gdw), followed by leaves and heads of the chicory plants in all treatments, with the concentrations exponentially decreasing with an increasing PFAA chain length in all plant compartments. The use of irrigation water as the delivery medium increased the transport of PFAAs to the aerial chicory parts, long-chain substances in particular. Additionally, the distribution of PFAAs in the soil was assessed by depth and compared with laboratory measured soil-water equilibrium partition coefficients, revealing only partial dependency of PFAAs bioavailability on the adsorption in soil.

Evaluation of morpho-physiological traits and contaminant accumulation ability in Lemna minor L. treated with increasing perfluorooctanoic acid (PFOA) concentrations under laboratory conditions.

There is increasing concern about the effects of releasing emerging contaminants (i.e. endocrine-disrupting chemicals, pharmaceuticals, personal-care products and flame retardants) into the environment. Particular attention is being paid to perfluoroalkyl substances (PFAS) because of their persistence and bioaccumulation, especially in the aquatic environment. In this paper, we present results of a study aimed at evaluating the effects of different perfluorooctanoic acid (PFOA) concentrations (2, 20 and 200 µg/L) on morpho-physiological traits in Lemna minor L. plants. The accumulation of PFOA in the plant's tissues was also monitored. L. minor was selected as a model plant for ecotoxicological studies, and we performed a seven-day assay for this investigation. The results highlight the lack of inhibitory effects on biometric parameters such as mean frond area, total frond number, multiplication rate, doubling time of frond number and average specific growth rate, for each of tested PFOA concentrations. Also, at photosynthetic level, physiological measurements showed that chlorophyll content and electron transport rate (ETR) were not affected by the exposure to PFOA. Remarkably, the chlorophyll fluorescence images, used for the first time in a study on PFOA, evidenced no impairment to the photosynthetic efficiency, measured by the maximum quantum yield of photosystem II (PSII) photochemistry (Fv/Fm), the quantum efficiency of PSII photochemistry (ΦPSII) and the non-photochemical quenching (NPQ) over the leaf surface of PFOA-treated plants, in comparison to control. Quantification of PFOA in the growth medium at the end of the seven-day test revealed no statistically different concentrations in plates with or without L. minor plants. We detected increasing PFOA accumulation in plant tissues, in accordance with the PFOA concentrations in the medium. Therefore, the L. minor plants were capable of taking up and accumulating PFOA. The ecological impact of the environmentally relevant PFOA concentrations tested in this work on biological organisms of the aquatic environment is discussed.

Linking sub-individual and supra-individual effects in Daphnia magna exposed to sub-lethal concentration of chlorpyrifos.

The main objective of the present study was to investigate possible links between sub-individual and supra-individual levels (i.e. population level) biomarkers in D. magna exposed to sublethal concentrations of the insecticide chlorpyrifos (CPF). To achieve the aim, 8-day old individuals were exposed for 96 h to two environmentally relevant concentrations of CPF (50 and 250 ng/L). Sub-individual level effects were investigated by measuring the activity of antioxidant (SOD, CAT, and GPx) and detoxifying (GST) enzymes, as well as by measuring the acetylcholinesterase (AChE) inhibition. In addition, the effects at supra-individual level were assessed by using a video-tracking system and analyzing changes in swimming capabilities (i.e. percentage of activity time, distance moved, and velocity). Our data have shown that daphnids exposed to both CPF concentrations were in a condition of stress which was highlighted by changes in both sub- and supra-individual biomarkers. Moreover, our results highlighted that the lowest tested CPF concentration did not modulate the antioxidant and detoxifying enzymes, whereas, an inhibition of AChE and a decrease of some parameters related to swimming behaviour (distance moved and velocity) were noted. On the contrary, significant changes in all the sub-individual biomarkers were measured at the highest tested concentration. In addition, organisms recovered the movement capability (distance moved) and also activate a mechanism of avoidance (increased swimming velocity). On the other hand, a reduction in the percent of active time was measured and this was attributed to the energy spent by organisms to activate antioxidant and detoxifying enzymes and the mechanism of avoidance. Based on these results, our study suggests the existence of a link between sub- and supra-individual levels, as the activation or non-activation in the antioxidant and detoxifying enzymes activities can led to different modifications of the swimming behaviour in D. magna.

Benzoylecgonine exposure induced oxidative stress and altered swimming behavior and reproduction in Daphnia magna.

Several monitoring studies have shown that benzoylecgonine (BE) is the main illicit drug residue commonly measured in the aquatic system worldwide. Few studies have investigated the potential toxicity of this molecule towards invertebrate and vertebrate aquatic non-target organisms focusing on effects at low levels of the biological organization, but no one has assessed the consequences at higher ones. Thus, the present study was aimed at investigating the toxicity of a 48-h exposure to two concentrations of BE, similar to those found in aquatic ecosystems (0.5 µg/L and 1.0 µg/L), on the cladoceran Daphnia magna at different levels of the ecological hierarchy. We relied on a multi-level approach focusing on the effects at biochemical/biomolecular (biomarkers), individual (swimming activity) and population (reproduction) levels. We measured the amount of reactive oxygen species and of the activity of antioxidant (SOD, CAT, and GPx) and detoxifying (GST) enzymes to assess if BE exposure can alter the oxidative status of D. magna specimens, while the lipid peroxidation (TBARS) was measured as a marker of oxidative damage. Moreover, we also measured the acetylcholinesterase (AChE) activity because it is strictly related to behavioral changes in aquatic organisms. Changes in swimming behavior were investigated by a video tracking analysis, while the consequences on reproduction were assessed by a chronic toxicity test. Our results showed that BE concentrations similar to those found in aquatic ecosystems induced oxidative stress and inhibited AChE activity, affecting swimming behavior and the reproduction of Daphnia magna individuals.

Bacteria contribute to pesticide degradation in cryoconite holes in an Alpine glacier.

Organic contaminants deposited on glacier snow and ice are subject to partitioning and degradation processes that determine their environmental fate and, consequently, their accumulation in ice bodies. Among these processes, organic compound degradation by supraglacial bacteria has been investigated to a lesser extent than photo- and chemical degradation. We investigated biodegradation of the organophosphorus insecticide chlorpyrifos (CPF), a xenobiotic tracer that accumulates on glaciers after atmospheric medium- and long-range transport, by installing in situ microcosms on an Alpine glacier to simulate cryoconite hole systems. We found that biodegradation contributed to the removal of CPF from the glacier surface more than photo- and chemical degradation. The high concentration of CPF (2-3 µg g-1 w.w.) detected in cryoconite holes and the estimated half-life of this compound (35-69 days in glacier environment) indicated that biodegradation can significantly reduce CPF concentrations on glaciers and its runoff to downstream ecosystems. The metabolic versatility of cryoconite bacteria suggests that these habitats might contribute to the degradation of a wide class of pollutants. We therefore propose that cryoconite acts as a "biofilter" by accumulating both pollutants and biodegradative microbial communities. The contribution of cryoconite to the removal of organic pollutants should be included in models predicting the environmental fate of these compounds in cold areas.

Legacy and emerging contaminants in meltwater of three Alpine glaciers.

Meltwater samples collected in early and late summer from three Alpine glaciers were analysed to determine the occurrence of POPs (Persistent Organic Pollutants: DDTs, HCHs and PCBs) and emerging contaminants (current used pesticides and polycyclic musk fragrances). For legacy POPs, we reconstructed a concentration time series using data from previous surveys in the same areas (starting from 2000). The results suggest a declining tendency of these compounds, probably related to the introduction of international regulations, which has led the strong use reduction and ban of these compounds. Among the analysed current used pesticides the terbuthylazine and chlorpyrifos were found in all the analysed samples. The experimental results were in line with the prediction of the OECD tool screening model, which was applied to estimate the potential of these substances to undergo regional-scale atmospheric transport processes. Temporal and spatial differences in concentrations for these compounds were related to the timing of applications, weather conditions and crop distribution along the adjacent Po River Plain. Despite model predictions, the herbicide pendimethalin was never detected, probably due to the lower use of this compound in the agricultural practices. Conversely, concentrations of polycyclic musk fragrances galaxolide and tonalide were more homogeneous both temporally and spatially, in agreement with their continuous release from emission sources.

Babies born with gastroschisis and followed up to the age of six years faced long-term morbidity and impairments.

AIM: The aims of this Argentinian study were to describe and analyse the outcomes of a continuous interdisciplinary follow-up programme of patients with gastroschisis. METHODS: This was a prospective, longitudinal study of babies with gastroschisis admitted from 1 November 2003 to 31 October 2014, and this paper presents results at one, three and six years of age. Matched-pairs analyses were carried out when they were one and six. RESULTS: We enrolled 62 babies and assessed 52 at one year of age, 34 at three years and 17 at six years. This showed that 63% had mental health problems and 5% had recurrent wheezing. Normal outcomes at one, three and six years were growth (80%, 85% and 80%), neurology-psychomotor development index (64%, 50% and 82%), audiology (100%, 76% and 76%), vision (98%, 94% and 89%) and language (55%, 62% and 65%). The rehospitalisation rates were 30%, 0.3% and zero, and the surgical re-intervention rates were 9%, 0.3% and 12%. Matched-pairs analysis showed no significant differences between outcomes at the ages of one and six. CONCLUSION: Babies born with gastroschisis were at risk for long-term morbidity and impairments, according to follow-up assessments at the ages of one, three and six years.

Seasonality of respiratory syncytial virus in Buenos Aires. Relationship with global climate change.

INTRODUCTION: Global climate change circulation pattern respiratory syncytial virus (RSV). We assessed whether RSV season has changed over the past 20 years and its correlation with mean annual temperature. METHODS: Cross-sectional study that included records of RSV and temperatures from Buenos Aires (1995-2014). RSV season onset, offset and duration, and its correlation with mean annual temperature were described for each year. RESULTS: A total of 8109 RSV infections were identified. The duration of RSV season reduced significantly (1995: 29 weeks vs. 2014: 17 weeks; R: 0.6; p < 0.001) due to an early ending (1995: week 45 vs. 2014: week 33; R: 0.6; p < 0.001). No correlation was observed between mean annual temperature and RSV season start, end and duration. CONCLUSIONS: Over the past 20 years, RSV season shortened significantly, but no correlation with temperature was observed.

INTRODUCTION: El cambio climático global podría modificar la circulación del virus sincicial respiratorio (VSR). Evaluamos si la temporada de VSR se modificó en los últimos 20 años y su correlación con la temperatura media anual. METHODS: Estudio transversal, en el que se utilizaron registros de VSR y temperatura de la Ciudad de Buenos Aires (19952014). Para cada año, describimos el inicio, el fin y la duración de la temporada de VSR y su correlación con la temperatura media anual. RESULTS: Se identificaron 8109 infecciones por VSR. La duración de la temporada disminuyó significativamente (1995: 29 semanas vs. 2014: 17 semanas; R: 0,6; p < 0,001), debido a una finalización más precoz (1995: semana 45 vs. 2014: semana 33; R: 0,6; p < 0,001). No se observó correlación entre la temperatura media anual y la duración, el comienzo ni la finalización de la temporada de VSR. CONCLUSIONS: En los últimos 20 años, la duración de la temporada de VSR se acortó significativamente, sin correlación con la temperatura.

[Infant Mortality in Argentina: reducibility criteria, 3rd review]. / Mortalidad infantil en Argentina: 3a revisión de los criterios de reducibilidad.

The infant mortality rate is an indicator of quality of life, development, and quality and accessibility of health care. Improvements in science, technology and better access to health care have contributed to a major decrease in the infant mortality rate in Argentina. Since the 1980s, infant deaths have been classified based on the opportunities for reducibility yielded by scientific knowledge and available technologies, in order to obtain a basis for the monitoring and implementation of health policies. The last review of this classification was in 2011. In 2012, a total of 5,541 neonatal deaths (less than 28 days of life) were registered and, under this new classification, over 61% were reducible mainly by the improvement of perinatal health care and adequate and timely treatment of the at-risk newborn. In 2012, a total of 2,686 post-neonatal deaths (from 28 days of life to a year) were registered and, under this new classification, over 66.8% were reducible by improving prevention strategies and providing adequate and timely treatment. This new analysis demonstrates the need to improve the opportunity, accessibility and quality of perinatal care starting at pregnancy, guaranteeing quality care at delivery and reinforcing prevention and timely treatment of common diseases in childhood over the first year of life.