An α-helical peptide-based plasmonic biosensor for highly specific detection of α-synuclein toxic oligomers.

BACKGROUND: α-Synuclein (αS) aggregation is the main neurological hallmark of a group of neurodegenerative disorders, collectively referred to as synucleinopathies, of which Parkinson's disease (PD) is the most prevalent. αS oligomers are elevated in the cerebrospinal fluid (CSF) of PD patients, standing as a biomarker for disease diagnosis. However, methods for early PD detection are still lacking. We have recently identified the amphipathic 22-residue peptide PSMα3 as a high-affinity binder of αS toxic oligomers. PSMα3 displayed excellent selectivity and reproducibility, binding to αS toxic oligomers with affinities in the low nanomolar range and without detectable cross-reactivity with functional monomeric αS. RESULTS: In this work, we leveraged these PSMα3 unique properties to design a plasmonic-based biosensor for the direct detection of toxic oligomers under label-free conditions. SIGNIFICANCE AND NOVELTY: We describe the integration of the peptide in a lab-on-a-chip plasmonic platform suitable for point-of-care measurements of αS toxic oligomers in CSF samples in real-time and at an affordable cost, providing an innovative biosensor for PD early diagnosis in the clinic.

Validation of a plasmonic-based serology biosensor for veterinary diagnosis of COVID-19 in domestic animals.

The coronavirus disease 2019 (COVID-19) pandemic recently demonstrated the devastating impact on public health, economy, and social development of zoonotic infectious diseases, whereby viruses jump from animals to infect humans. Due to this potential of viruses to cross the species barrier, the surveillance of infectious pathogens circulation in domestic and close-to-human animals is indispensable, as they could be potential reservoirs. Optical biosensors, mainly those based on Surface Plasmon Resonance (SPR), have widely demonstrated its ability for providing direct, label-free, and quantitative bioanalysis with excellent sensitivity and reliability. This biosensor technology can provide a powerful tool to the veterinary field, potentially being helpful for the monitoring of the infection spread. We have implemented a multi-target COVID-19 serology plasmonic biosensor for the rapid testing and screening of common European domestic animals. The multi-target serological biosensor assay enables the detection of total SARS-CoV-2 antibodies (IgG + IgM) generated towards both S and N viral antigens. The analysis is performed in less than 15 min with a low-volume serum sample (<20 µL, 1:10 dilution), reaching a limit of detection of 49.6 ng mL-1. A complete validation has been carried out with hamster, dog, and cat sera samples (N = 75, including 37 COVID-19-positive and 38 negative samples). The biosensor exhibits an excellent diagnostic sensitivity (100 %) and good specificity (71.4 %) for future application in veterinary settings. Furthermore, the biosensor technology is integrated into a compact, portable, and user-friendly device, well-suited for point-of-care testing. This study positions our plasmonic biosensor as an alternative and reliable diagnostic tool for COVID-19 serology in animal samples, expanding the applicability of plasmonic technologies for decentralized analysis in veterinary healthcare and animal research.

Glucose boosts protein oxidation/nitration during simulated gastric digestion of myofibrillar proteins by creating a severe pro-oxidative environment.

The severe pro-oxidative environment in the stomach promotes oxidation of dietary components. The pro-oxidant molecular mechanisms of reducing sugars on this environment are unknown. To investigate the mechanisms involved in protein oxidation and nitration during a simulated gastric digestion (porcine pepsin, 37 °C, 2 h) of meat proteins, these were exposed to several dietary reactive components namely myoglobin, glucose, glyoxal, myoglobin + glucose and myoglobin + glyoxal. Two versions of each experimental unit were prepared depending on the addition or absence of nitrite. Compared to control (only meat proteins), myoglobin + glucose showed the highest pro-oxidative and pro-nitrosative effect (p < 0.001), likely caused by an increase in ROS derived from the degradation of glucose during assay. Nitrite promoted the occurrence of protein nitration but decreased protein oxidation in myoglobin-added groups (p < 0.001) by, plausibly, stabilizing heme iron. These results indicate the relevant role of glyco-oxidation during digestion of red meat with other dietary components such as reducing sugars.

Proteomics reveal the protective effects of chlorogenic acid on Enterococcus faecium Q233 in a simulated pro-oxidant colonic environment.

Certain phytochemicals have been found to promote the beneficial effects of probiotic bacteria although the molecular mechanisms of such interactions are poorly understood. The objective of the present study was to evaluate the impact of the exposure to 0.5 mM chlorogenic acid (CA) on the redox status and proteome of Enterococcus faecium isolated from cheese and challenged with 2.5 mM hydrogen peroxide (H2O2). The bacterium was incubated in anaerobic conditions for 48 h at 37 °C. CA exposure led to a more intense oxidative stress and accretion of bacterial protein carbonyls than those induced by H2O2. The oxidative damage to bacterial proteins was even more severe in the bacterium treated with both CA and H2O2, yet, such combination led to a strengthening of the antioxidant defenses, namely, a catalase-like activity. The proteomic study indicated that H2O2 caused a decrease in energy supply and the bacterium responded by reinforcing the membrane and wall structures and counteracting the redox and pH imbalance. CA stimulated the accretion of proteins related to translation and transcription regulators, and hydrolases. This phytochemical was able to counteract certain proteomic changes induced by H2O2 (i.e. increase of ATP binding cassete (ABC) transporter complex) and cause the increase of Rex, a redox-sensitive protein implicated in controlling metabolism and responses to oxidative stress. Although this protection should be confirmed under in vivo conditions, such effects point to benefits in animals or humans affected by disorders in which oxidative stress plays a major role.

Utilidad de una estrategia nutricional sobre la dislipidemia en pacientes pediátricos con enfermedad renal crónica terminal / Usefulness of a nutritional strategy on dyslipidemia in pediatric patients with terminal chronic kidney disease

Antecedentes y objetivo: en la enfermedad renal crónica (ERC) existen múltiples factores que incrementan la presencia de la dislipidemia. El objetivo fue identificar la utilidad de una intervención nutricional sobre la dislipidemia, en niños con ERC terminal, a los 6 meses del inicio de la intervención. Materiales y métodos: estudio cuasiexperimental (antes y después). Se incluyeron pacientes con ERC terminal en diálisis peritoneal y hemodiálisis. A cada niño se le realizaron una somatometría y un perfil de lípidos al inicio y a los 6 meses de seguimiento. Se realizó un manual de alimentación con semaforización de los alimentos, poniendo de color rojo los alimentos que se deben consumir en la menor cantidad posible, además de incluir alimentos a tamaño real utilizando modelos educativos. Para comparar las variables cuantitativas antes y después de la intervención se transformaron las variables a su logaritmo y se aplicó la “t” de Student pareada. Resultados: se analizaron 41 pacientes. Posteriormente a la intervención se modificaron los parámetros del perfil lipídico; las concentraciones de HDL se incrementaron (41,0 mg/dL vs. 44,4 mg/dL, p = 0,048), mientras que las concentraciones de triglicéridos disminuyeron (227,1 mg/dL vs. 185.9 mg/dL, p = 0,007), lo cual persiste incluso una vez excluidos aquellos pacientes que se encontraban bajo tratamiento hipolipemiante (195 mg/dL vs. 171,6, p = 0,049). En cuanto al estado de dislipidemia, la hipertrigliceridemia disminuyó sin alcanzar la significancia (80,5 % vs. 62,5 %, p = 0,073). Conclusiones: la intervención nutricional mejoró las concentraciones de HDL y triglicéridos pasados 6 meses de la intervención en niños con ERC terminal (AU)

Background and objective: in chronic kidney disease (CKD) there are several factors that increase the presence of dyslipidemia. The aim of this study was to identify the usefulness of a nutritional intervention, in children with terminal CKD, on dyslipidemia 6 months after intervention start. Materials and methods: a quasi-experiment study (before and after) was performed. End-stage CKD patients on peritoneal dialysis and hemodialysis were included. Each child underwent a determination somatometry, and lipid profile at the beginning and at 6 months of follow-up. A nutritional guide was made with food traffic lights, turning the food that should be consumed in the least amount possible in red. In addition to including life-size food using educational models. To compare the quantitative variables before and after the intervention, the variables were transformed to their logarithm and a paired Student's t-test was applied. Results: a total of 41 patients were analyzed. After the intervention, the parameters in the lipid profile were modified; meanwhile HDL concentrations increased (41.0 mg/dL vs 44.4 mg/dL, p = 0.048), triglyceride concentrations decreased (227.1 mg/dL vs 185.9 mg/dL, p = 0.007), and these changes persist even after excluding patients who were under lipid-lowering treatment (195 mg/dL vs 171.6, p = 0.049). Regarding the state of dyslipidemia, hypertriglyceridemia decreased, without reaching significance (80.5 % vs 62.5 %, p = 0.073). Conclusions: the nutritional intervention improved HDL and triglyceride concentrations 6 months afterwards in children with terminal CKD (AU)

The role of afforestation species as a driver of Hg accumulation in organic horizons of forest soils from a Mediterranean mountain area in SW Europe.

Forest areas are a primary sink of atmospheric mercury (Hg) within terrestrial ecosystems, whereas forest vegetation plays a key role in atmospheric Hg transfer to soil horizons. This study assessed variations in total Hg contents (HgT) and accumulation (HgRes) in the soil organic horizons of a forest area in NE Portugal, where post-wildfire afforestation led to the substitution of the native deciduous species (Quercus pyrenaica) by fast-growing coniferous species (Pseudotsuga menziesii and Pinus nigra). The study also evaluated, for each species, the links between Hg contents and other biophilic elements of soil organic matter (C, N, S) present in organic subhorizons (OL, OF, OH). Mean HgT in the organic horizons of the different tree species follow the sequence: P. nigra (88 µg kg-1) < Q.pyrenaica (101 µg kg-1)

[Reprint of: Severe pre-eclampsia: guidelines for clinical practice from the French Society of anesthesiology and intensive care (SFAR) and the French College of gynaecologists and obstetricians (CNGOF)]. / Republication de : recommandations formalisées d'experts. Prise en charge de la patiente avec une pré-éclampsie sévère­RFE communes Société française d'anesthésie-réanimation (SFAR)­Collège national des gynécologues et obstétriciens français (CGNOF).

OBJECTIVE: To provide national guidelines for the management of women with severe preeclampsia. DESIGN: A consensus committee of 26 experts was formed. A formal conflict of interest (COI) policy was developed at the onset of the process and enforced throughout. The entire guidelines process was conducted independently of any industrial funding. The authors were advised to follow the principles of the Grading of Recommendations Assessment, Development and Evaluation (GRADE®) system to guide assessment of quality of evidence. The potential drawbacks of making strong recommendations in the presence of low-quality evidence were emphasized. METHODS: The last SFAR and CNGOF guidelines on the management of women with severe preeclampsia was published in 2009. The literature is now sufficient for an update. The aim of this expert panel guidelines is to evaluate the impact of different aspects of the management of women with severe preeclampsia on maternal and neonatal morbidities separately. The experts studied questions within 7 domains. Each question was formulated according to the PICO (Patients Intervention Comparison Outcome) model and the evidence profiles were produced. An extensive literature review and recommendations were carried out and analyzed according to the GRADE® methodology. RESULTS: The SFAR/CNGOF experts panel provided 25 recommendations: 8 have a high level of evidence (GRADE 1±), 9 have a moderate level of evidence (GRADE 2±), and for 7 recommendations, the GRADE method could not be applied, resulting in expert opinions. No recommendation was provided for 3 questions. After one scoring round, strong agreement was reached between the experts for all the recommendations. CONCLUSIONS: There was strong agreement among experts who made 25 recommendations to improve practices for the management of women with severe preeclampsia.

Critical overview of the use of plant antioxidants in the meat industry: Opportunities, innovative applications and future perspectives.

The number of articles devoted to study the effect of "natural antioxidants" on meat systems has remarkably increased in the last 10 years. Yet, a critical review of literature reveals recurrent flaws in regards to the rationale of the application, the experimental design, the characterisation of the plant sources, the discussion of the molecular mechanisms and of the potential benefits. The selection of the appropriate source of these antioxidants and the identification of their bioactive constituents, are essential to understand their mode of action and set effective and safe doses. The methodological approach should also be planned with care as the recorded effects and main conclusions largely depend on the accuracy and specificity of the methods. This article aims to critically review the recent advances in the application of plant antioxidants in meat and meat products and briefly covers current trends of innovative application and future trends.

Liver development is restored by blastocyst complementation of HHEX knockout in mice and pigs.

BACKGROUND: There are over 17,000 patients in the US waiting to receive liver transplants, and these numbers are increasing dramatically. Significant effort is being made to obtain functional hepatocytes and liver tissue that can for therapeutic use in patients. Blastocyst complementation is a challenging, innovative technology that could fundamentally change the future of organ transplantation. It requires the knockout (KO) of genes essential for cell or organ development in early stage host embryos followed by injection of donor pluripotent stem cells (PSCs) into host blastocysts to generate chimeric offspring in which progeny of the donor cells populate the open niche to develop functional tissues and organs. METHODS: The HHEX gene is necessary for proper liver development. We engineered loss of HHEX gene expression in early mouse and pig embryos and performed intraspecies blastocyst complementation of HHEX KO embryos with eGFP-labeled PSCs in order to rescue the loss of liver development. RESULTS: Loss of HHEX gene expression resulted in embryonic lethality at day 10.5 in mice and produced characteristics of lethality at day 18 in pigs, with absence of liver tissue in both species. Analyses of mouse and pig HHEX KO fetuses confirmed significant loss of liver-specific gene and protein expression. Intraspecies blastocyst complementation restored liver formation and liver-specific proteins in both mouse and pig. Livers in complemented chimeric fetuses in both species were comprised of eGFP-labeled donor-derived cells and survived beyond the previously observed time of HHEX KO embryonic lethality. CONCLUSIONS: This work demonstrates that loss of liver development in the HHEX KO can be rescued via blastocyst complementation in both mice and pigs. This complementation strategy is the first step towards generating interspecies chimeras for the goal of producing human liver cells, tissues, and potentially complete organs for clinical transplantation.

Environmental relevance of adsorption of doxycycline, enrofloxacin, and sulfamethoxypyridazine before and after the removal of organic matter from soils.

In this work batch-type experiments were used to study the adsorption of the antibiotics doxycycline (DC), enrofloxacin (ENR), and sulfamethoxypyridazine (SMP) in cultivation soils, before and after the removal of soil organic matter. Organic matter removal by calcination resulted not only in C and N removal, but also in increased soil pH, exchangeable basic cations and surface area values. The results indicate a very different behavior depending on the type of antibiotic, showing the adsorption sequence DC > ENR > SMP. Specifically, DC adsorption was very high in untreated soil samples (with organic matter), and was still high (although decreased) after the removal of soil organic matter. Furthermore, the adsorption behavior of DC was clearly dependent on the pH of the medium. Regarding ENR, it also showed high adsorption, although to a lesser extent than DC. However, when soil organic matter was removed, ENR adsorption significantly decreased in all soil samples. As regards SMP, it was adsorbed to a much lesser extent, and the removal of soil organic matter caused an additional drastic decrease in adsorption, reaching negligible values in some samples. Desorption followed the reverse sequence of adsorption, specifically in the order DC < ENR < SMP. In the case of DC, desorption was negligible, both in samples with and without organic matter, while for ENR and SMP, desorption clearly increased for soil samples where organic matter was removed. These results may be of relevance as regards environmental quality and public health, especially to facilitate a correct use of soils and organic amendments in areas that receive the application of substances containing the investigated antibiotics.

Real-time monitoring of fenitrothion in water samples using a silicon nanophotonic biosensor.

Due to the large quantities of pesticides extensively used and their impact on the environment and human health, a prompt and reliable sensing technique could constitute an excellent tool for in-situ monitoring. With this aim, we have applied a highly sensitive photonic biosensor based on a bimodal waveguide interferometer (BiMW) for the rapid, label-free, and specific quantification of fenitrothion (FN) directly in tap water samples. After an optimization protocol, the biosensor achieved a limit of detection (LOD) of 0.29 ng mL-1 (1.05 nM) and a half-maximal inhibitory concentration (IC50) of 1.71 ng mL-1 (6.09 nM) using a competitive immunoassay and employing diluted tap water. Moreover, the biosensor was successfully employed to determine FN concentration in blind tap water samples obtaining excellent recovery percentages with a time-to-result of only 20 min without any sample pre-treatment. The features of the biosensor suggest its potential application for real time, fast and sensitive screening of FN in water samples as an analytical tool for the monitoring of the water quality.

Sulfadiazine, sulfamethazine and sulfachloropyridazine removal using three different porous materials: Pine bark, "oak ash" and mussel shell.

This work focuses on studying the efficacy of three different by-products to adsorb three antibiotics (sulfadiazine, SDZ; sulfamethazine, SMT; sulfachloropyridazine, SCP). These antibiotics can be considered pollutants of the environment when they reach water, as well as in cases where they are spread on soils through irrigation or contained in sewage sludge or livestock manure. In this study, batch-type adsorption/desorption experiments were performed for each of the three sulfonamides, adding 7 different concentrations of the antibiotics, going from 1 to 50 µmol L-1, and with contact time of 24 h. The results indicate that pine bark is the most efficient bioadsorbent among those studied, as it adsorbs up to 95% of the antibiotics added, while desorption is always less than 11%. However, for "oak ash" and mussel shell the adsorption is always lower than 45 and 15%, respectively, and desorption is high, reaching up to 49% from "oak ash" and up to 81% from mussel shell. Adsorption data showed good fitting to the Linear and Freundlich models, with R2 values between 0.98 and 1.00 in both cases. Kd and KF adsorption parameters showed similar values for the same sorbent materials but were much higher for pine bark than for the other two bioadsorbents. The Freundlich's n parameter showed values in the range 0.81-1.28. The highest KF values (and therefore the highest adsorption capacities) were obtained for the antibiotic SCP in pine bark. Pine bark showed the highest capacity to adsorb each of the antibiotics, increasing as a function of the concentration added. When the concentration of sulfonamide added was 50 µM, the amounts adsorbed were 780 µmol kg-1 for SDZ, 890 µmol kg-1 for SMT, and 870 µmol kg-1 for SCP. "Oak ash" and mussel shell have low adsorption capacity for all three sulfonamides, showing values always lower than 150 µmol kg-1 (oak ash) and 20 µmol kg-1 (mussel shell) when a concentration of 50 µmol L-1 of antibiotic is added. The results of this study could aid to make an appropriate management of the by-products studied, in order to facilitate their valorization and recycling in the treatment of environmental compartments polluted with sulfonamide antibiotics.

Sulfadiazine removal using green zero-valent iron nanoparticles: A low-cost and eco-friendly alternative technology for water remediation.

In this work, the effectiveness of green zero-valent iron nanoparticles (gnZVIs) for the removal of the antibiotic sulfadiazine (SDZ) from water via adsorption and reduction was tested. Additionally, the effectiveness of this material as a catalyst for the Fenton and photo-Fenton processes was also investigated. This represents the first study concerning the use of gnZVIs for the degradation of a sulfonamide antibiotic. The results obtained indicate that gnZVIs were able to remove up to 58% of SDZ via adsorption and up to 69% via adsorption plus reduction using a SDZ/Fe3+ molar ratio of 1:61.6. Furthermore, gnZVIs showed strong effectiveness as a catalyst for the Fenton and photo-Fenton reactions, with complete SDZ removal in 8 h and 5 min, respectively, using a SDZ/Fe3+/H2O2 molar ratio of 1:38.4:38.4. These results demonstrate that the use of gnZVIs constitutes an attractive and potential alternative technology for water remediation, reducing environmental impact and operational costs.

Effectiveness of Sprayed Bioactive Fruit Extracts in Counteracting Protein Oxidation in Lamb Cutlets Subjected to a High-Oxygen MAP.

High-oxygen packaging atmosphere (High-Ox-MAP) promotes meat protein oxidation and leads to texture deterioration. This study was conceived to assess the extent to which sprayed fruit extracts could inhibit the oxidative damage to proteins in lamb cutlets subjected to High-Ox-MAP (10 days/4 °C) and subsequent roasting (10 min/180 °C). Extracts from oaknut (Quercus ilex subsp. ballota; QI), rose hips (Rosa canina L.; RC), common hawthorn (Crataegus monogyna Jacq.; CM) and strawberry tree (Arbutus unedo L.; AU) were characterized for bioactive compounds (phenolic subclasses, tocopherols and ascorbic acid) and in vitro bioactivities. While the four fruits showed relevant antioxidant potential, CM had the highest phenolics and tocopherol content and that was reflected in efficient antiradical activity. The in vitro activity of this fruit to inhibit meat protein oxidation was, however, lower than that displayed by the other fruits. Taking the results altogether, CM was also found to be most efficient in protecting lamb cutlets from lipid oxidation. All fruits were able to inhibit thiols oxidation except RC, which seemed to reduce protein thiols. Among fruits, QI was the most efficient in protecting lamb cutlets against protein carbonylation as a plausible involvement of ellagitannins. The inhibition of protein oxidation by QI was reflected in significantly lower instrumental hardness in cooked lamb cutlets. Spraying lamb cutlets with extracts from QI, RC and CM improved consumers' purchase intention after chilled storage. This antioxidant strategy seems to be a feasible and efficient solution to the pro-oxidative effects caused by High-Ox-MAP in red meat.

[Perspectives of patients with Duchenne muscular dystrophy: A focal group to improve healthcare quality]. / Perspectivas de pacientes con distrofia muscular de Duchenne: grupo focal para mejorar la calidad asistencial.

INTRODUCTION: Duchenne muscular dystrophy is a complex disease that requires a multidisciplinary and coordinated approach. Given that therapeutic efforts are centred on improving the quality of life of the patient, the aim of this study is to find out the views of young people and adolescents with Duchenne muscular dystrophy, their families, and health professionals as regards the healthcare provided by the hospital in order to improve their quality of life. METHODS: A qualitative study was conducted using 3 focal groups consisting of patients, families, and healthcare professionals. A thematic guide was prepared, and the information from the interviews was gathered using a sound recorder. In order to analyse the information, the transcriptions were coded and the significant data of each interview were extracted and grouped into various topics. RESULTS/CONCLUSIONS: The main worries of the 3 groups were along the same line. On the one hand, the importance of a coordinated multidisciplinary team in the same unit that provides the integral care. On the other hand, sport as a common interest in these adolescents, and the consideration of a positive relationship between leisure and quality of life, finding that their participation in physiotherapy groups of great use. To achieve this objective, it is necessary to improve the coordination between the hospital and the different groups. The parents also demanded better cover in the social and psychological care offered by the hospital. Lastly, the importance of humanising the care was mentioned (privacy, adapting of structures, transmission of information, sexuality…).

[Chapter 1. Ethics and cultural diversity] / Chapitre 1. Éthique et diversité culturelle.

Man’s social nature and capabilities set him up as a creator of culture. Culture is inherent to its human nature and encompasses all the dimensions of its person, its biology, its intelligence, its affectivity and also its ethical dimension. There is no other being in our world that creates and transmits culture; culture is of man and for man. Therefore, it unites us to past generations and at the same time commits us to the future, since we assume the legacy of human history and develop our own to launch it into the future to create and participate in cultural advancement and progress.

[Chapter 3. The seven capital sins: genesis, virtues, demons and rights] / Chapitre 3. Los siete pecados capitales: genesis, virtudes, demonios y derechos.

Sin in its original form constitutes a deviation from human behavior. Christian doctrine incorporates into the Judeo-Christian tradition the deadly sins that we all know (and their demons), as well as the virtues that are supposed to defeat or at least neutralize: 1) pride / humility, 2) greed / generosity, 3) lust / chastity, 4) anger / patience, 5) gluttony / temperance, 6) envy / charity and 7) laziness / diligence. In this same line of thought, to sin would be to abuse the freedom of God. According to John Bossy, the seven deadly sins would be the expression of a social and community ethic with which the Catholic Church tried at the time to contain violence and heal the troubled medieval society. Sins and their penance were originally a healthy warning of how to manage one’s individual and social behavior (Savater, 2013). That which Modern society allows as lawful or not, has “overcome” the conduct and moral republicanism of our days (1). Morality is one of the most sophisticated features of human judgment, behavior, and mind. An individual who deviates from violent morality, rules and civil rights, even affecting the individual liberties of others, sometimes even aggressively. A scientific approach to the origins of evil refers us to the exciting analysis of the molecular, epigenetic, phylogenetic and cellular determinants of the neurobiology of sin. This formidable adventure of thought constitutes a harmonious path traveled by moral philosophy and the neurosciences of that long stretch that is between the error of Prometheus and the error of Descartes.

One-Step Immobilization of Antibodies and DNA on Gold Sensor Surfaces via a Poly-Adenine Oligonucleotide Approach.

Label-free plasmonic biosensors have demonstrated promising capabilities as analytical tools for the detection of virtually any type of biomarker. They are presented as good candidates for precision diagnostics since they offer highly sensitive, cost-effective solutions that can be used in any clinical or laboratory setting without the need for specialized trainees. However, different surface functionalization protocols are required, depending on the nature of the biorecognition element, limiting their capabilities for integrated multi-biomarker detection. Here, we present a simple, yet efficient, one-step immobilization approach that is common for both DNA probes and antibodies. Our immobilization approach relies on the incorporation of poly-adenine (polyA) blocks in both nucleic acid probes and antibodies. PolyA sequences have a remarkable affinity for gold surfaces and can specifically interact with sufficient strength to generate stable, dense, and highly ordered monolayers. We have demonstrated excellent performance of our universal functionalization method, showing limits of detection and quantification in the pM-nM range. Moreover, it was able to reduce up to 50% of the background signal from undiluted serum samples compared to conventional methods, demonstrating the immense potential of this strategy for the direct analysis of human biofluids, essential for rapid point-of-care diagnostics. The polyA-based immobilization approach is a promising alternative for the generation of multiplexed biosensors that can detect both protein and nucleic acid biomarkers for multiparametric diagnostic assays.

Single and simultaneous adsorption of three sulfonamides in agricultural soils: Effects of pH and organic matter content.

Veterinary antibiotics reaching the environment have become a matter of global concern, since they can cause serious negative impacts on human and ecological health. Therefore, a deep understanding of their behavior and fate once they reach the soil environment is of utmost importance to design and implement appropriate measures that could reduce their potential risks. With this aim, batch-type experiments were carried out to study competitive adsorption and desorption for three sulfonamide antibiotics (sulfadiazine -SDZ-, sulfamethazine -SMT-, and sulfachloropyridazine -SCP-) in six crop soils presenting different characteristics. The results obtained showed that sulfonamides have a low retention in soils, with average adsorption percentages of 40% for SDZ, 44% for SMT and 54% for SCP, and with desorption percentages up to 36% for SDZ and SCP and up to 29% for SMT. The retention of sulfonamides was strongly influenced by the soil organic carbon content (SOC), with higher adsorption and less desorption associated to higher SOC contents. In addition, the hydrophobicity of sulfonamides also had an influence, as higher hydrophobicity resulted in higher affinity for soils, showing the affinity sequences: SDZ ~ SMT