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3D printing has attracted the interest of researchers due to its creative freedom, low cost, and ease of operation. Because of these features, this technology has produced different types of electroanalytical platforms. Despite their popularity, the thermoplastic composites used for electrode fabrication typically have high electrical resistance, resulting in devices with poor electrochemical performance. Herein, we propose a new strategy to improve the electrochemical performance of 3D-printed electrodes and to gain chemical selectivity towards glucose detection. The approach involves synthesising a nanostructured gold film using an infrared laser source directly on the surface of low-contact resistance 3D-printed electrodes. The laser parameters, such as power, focal distance, and beam scan rate, were carefully optimised for the modification steps. Scanning electronic microscopy and energy-dispersive X-ray spectroscopy confirmed the morphology and composition of the nanostructured gold film. After modification, the resulting electrodes were able to selectively detect glucose, encouraging their use for sensing applications. When compared with a gold disc electrode, the gold-modified 3D-printed electrode provided a 44-fold current increase for glucose oxidation. As proof of concept, the devices were utilised for the non-enzymatic catalytic determination of glucose in drink samples, demonstrating the gold film's catalytic nature and confirming the analytical applicability with more precise results than commercial glucometers.

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The development of a portable analytical procedure is described for rapid sequential detection and quantification of the explosives 2,4,6-trinitrotoluene (TNT) and cyclotrimethylenetrinitramine (RDX) in forensic samples using a graphite sheet (GS). A single GS platform works as a collector of explosive residues and detector after its assembly into a 3D-printed cell. The detection strategy is based on cyclic square-wave stripping voltammetry. The cathodic scan from + 0.1 to -1.0 V with accumulation at 0.0 V enables the TNT detection (three reduction peaks), and the anodic scan from + 0.2 to + 1.55 V with accumulation at -0.9 V provides the RDX detection (two oxidation processes). Low detection limit values (0.1 µmol L-1 for TNT and 2.4 µmol L-1 for RDX) and wide linear ranges (from 1 to 150 µmol L-1 for TNT and from 20 to 300 µmol L-1 for RDX) were obtained. The sensor did not respond to pentaerythritol tetranitrate (PETN), which was evaluated as a potential interferent, because plastic explosives contain mixtures of TNT, RDX, and PETN. The GS electrode was also evaluated as a collector of TNT and RDX residues spread on different surfaces to simulate forensic scenarios. After swiping over different surfaces (metal, granite, wood, cloths, hands, money bills, and cellphone), the GS electrode was assembled in the 3D-printed cell ready to measure both explosives by the proposed method. In all cases, the presence of TNT and RDX was confirmed, attesting the reliability of the proposed device to act as collector and sensor.

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The ivermectin (IVM), as a broad-spectrum antiparasitic drug, was widely prescribed to treat COVID-19 during the pandemic, despite lacking proven efficacy in combating this disease. Therefore, it is important to establish affordable devices in laboratories with minimal infrastructure. The laser engraving technology has been revolutionary in sensor manufacturing, primarily attributed to the diversity of substrates that can be employed and the freedom it provides in creating sensor models. In this work, electrochemical sensors based on graphene were developed using the laser engraving technology for IVM sensing. Through, the studies that used the techniques of cyclic voltammetry and differential pulse voltammetry, following parameter optimization, for the laser-induced graphene electrode demonstrated a mass transport governed by adsorption of the species and exhibited a linear working range of 10-100 (µmol L-1), a limit of detection (LOD) of 1.6 × 10-6 (mol L-1), a limit of quantification (LOQ) of 4.8 × 10-6 (mol L-1), and a sensitivity of 0.139 (µA µmol L-1). The developed method was successfully applied to direct analysis of pharmaceutical tablets, tap water (recovery of 94%) and synthetic urine samples (recovery between 97% and 113%). These results demonstrate the feasibility of the method for routine analyses involving environmental samples.

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3D printing represents an emerging technology in several fields, including engineering, medicine, and chemistry [...].

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Lysergic acid diethylamide (LSD) and two phenethylamine classes (NBOHs and NBOMes) are the main illicit drugs found in seized blotter papers. The preliminary identification of these substances is of great interest for forensic analysis. In this context, this work constitutes the inaugural demonstration of an efficient methodology for the selective detection of LSD, NBOHs, and NBOMes, utilizing a fully 3D-printed electrochemical double cell (3D-EDC). This novel 3D-EDC enables the use of two working electrodes and/or two supporting electrolytes (at different pHs) in the same detection system, with the possibility of shared or individual auxiliary and pseudo-reference electrodes. Thus, the selective voltammetric detection of these substances is proposed using two elegant strategies: (i) utilizing the same 3D-EDC platform with two working electrodes (boron-doped diamond (BDD) and 3D-printed graphite), and (ii) employing two pH levels (4.0 and 12.0) with 3D-printed graphite electrode. This comprehensive framework facilitates a fast, robust, and uncomplicated electrochemical analysis. Moreover, this configuration enables a rapid and sensitive detection of LSD, NBOHs, and NBOMes in seized samples, and can also provide quantitative analysis. The proposed method showed good stability of the electrochemical response with RSD <9 % for Ip and <5 % for Ep, evaluating all oxidation processes observed for studied analytes (n = 7) at two pH levels, using the same and different (n = 3) working electrodes. It demonstrates a broad linear range (20-100 and 20-70 µmol L-1) and a low LOD (1.0 µmol L-1) for quantification of a model molecule (LSD) at the two pHs studied. Hence, the 3D-EDC combined with voltammetric techniques using BDD and 3D-printed graphite electrodes on the same platform, or only with this last sensor at two pH values, provide a practical and robust avenue for preliminary identification of NBOHs, NBOMes, and LSD. This method embodies ease, swiftness, cost-efficiency, robustness, and selectivity as an on-site screening tool for forensic analysis.

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Secondary tropical forests play an increasingly important role in carbon budgets and biodiversity conservation. Understanding successional trajectories is therefore imperative for guiding forest restoration and climate change mitigation efforts. Forest succession is driven by the demographic strategies-combinations of growth, mortality and recruitment rates-of the tree species in the community. However, our understanding of demographic diversity in tropical tree species stems almost exclusively from old-growth forests. Here, we assembled demographic information from repeated forest inventories along chronosequences in two wet (Costa Rica, Panama) and two dry (Mexico) Neotropical forests to assess whether the ranges of demographic strategies present in a community shift across succession. We calculated demographic rates for >500 tree species while controlling for canopy status to compare demographic diversity (i.e., the ranges of demographic strategies) in early successional (0-30 years), late successional (30-120 years) and old-growth forests using two-dimensional hypervolumes of pairs of demographic rates. Ranges of demographic strategies largely overlapped across successional stages, and early successional stages already covered the full spectrum of demographic strategies found in old-growth forests. An exception was a group of species characterized by exceptionally high mortality rates that was confined to early successional stages in the two wet forests. The range of demographic strategies did not expand with succession. Our results suggest that studies of long-term forest monitoring plots in old-growth forests, from which most of our current understanding of demographic strategies of tropical tree species is derived, are surprisingly representative of demographic diversity in general, but do not replace the need for further studies in secondary forests.

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OBJECTIVE: To evaluate the efficiency of the sepsis risk calculator and the serial clinical observation in the management of late preterm and term newborns with infectious risk factors. METHOD: Single-center, observational, two-phase cohort study comparing the rates of neonates born ≥35 weeks' gestation, ≥2000 g birthweight, and without major congenital anomalies, who were screened and/or received antibiotics for early-onset neonatal sepsis risk at our center during two periods, before (January/2018-June/2019) and after (July/2019-December/2020) the implementation of the sepsis risk calculator. RESULTS: A total of 1796 (Period 1) and 1867 (Period 2) patients with infectious risk factors were included. During the second period, tests to rule out sepsis were reduced by 34.0 % (RR, 95 %CI): 0.66 (0.61, 0.71), blood cultures by 13.1 %: 0.87 (0.77, 0.98), hospital admissions by 13.5 %: 0.86 (0.76, 0.98) and antibiotic administration by 45.9 %: 0.54 (0.47, 0.63). Three cases of early-onset neonatal sepsis occurred in the first period and two in the second. Clinical serial evaluation would have detected all true cases. CONCLUSIONS: The implementation of a sepsis risk calculator in the management of newborns ≥35 weeks GA, ≥2000 g birthweight, without major congenital anomalies, with infectious risk factors is safe and adequate to reduce laboratory tests, blood cultures, hospital admissions, and antibiotics administration. Serial clinical observation, in addition, could be instrumental to achieve or even improve this goal.

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AIMS: To evaluate the antifungal and antibiofilm activity of gallic acid derivatives TPP+-C10 and TPP+-C12 and their effects on mitochondrial function on two Candida albicans reference strains (ATCC 90029 and ATCC 10231). METHODS AND RESULTS: First, we determined minimal inhibitory concentration (MIC) using a microdilution assay. Both compounds exerted antifungal effects, and their MICs ranged from 3.9 to 13 µM, with no statistically significant differences between them (P > 0.05, t-test). These concentrations served as references for following assays. Subsequently, we measured oxygen consumption with a Clark electrode. Our observations revealed that both drugs inhibited oxygen consumption in both strains with TPP+-C12 exerting a more pronounced inhibitory effect. We then employed flow cytometry with TMRE as a probe to assess mitochondrial membrane potential. For each strain assayed, the compounds induced a decay in transmembrane potential by 75%-90% compared to the control condition (P < 0.05, ANOVA). Then, we measured ATP levels using a commercial kit. TPP+-C12 showed a 50% decrease of ATP content (P < 0.05 ANOVA), while TPP+-C10 exhibited a less pronounced effect. Finally, we assessed the antibiofilm effect using the MTT reduction assay. Both compounds were effective, but TPP+-C12 displayed a greater potency, requiring a lower concentration to inhibit 50% of biofilms viability (P < 0.05, t-test). CONCLUSIONS: Derivatives of gallic acid linked to a TPP+ group exert antifungal and antibiofilm activity through impairment of mitochondrial function in C. albicans.

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Antecedentes: El Shock Cardiogénico (SC) y las Angioplastías de Alto Riesgo (AAR) están asociadas con altas tasas de mortalidad. El uso del dispositivo Impella CP podría reducir el riesgo de muerte en estos escenarios. En Chile no existen reportes evaluando el uso del dispositivo Impella CP. Objetivo: Analizar los desenlaces clínicos en pacientes que fueron sometidos al uso del dispositivo Impella CP por SC o por AAR. Métodos: Se realizó un estudio retrospectivo en 17 pacientes, los cuales representan el total de implantes realizados en el país, entre octubre 2021 y agosto 2023. Se describió las características, demográficas, procedimentales y después del implante. Se estimó la mortalidad general y se identificaron factores asociados. Resultados: La edad de los pacientes fue 69± 3,7 años y 88,2% fueron hombres. El 64,7% recibió el dispositivo por SC y 35,3% por AAR. Dentro de las comorbilidades estudiadas, la hipertensión arterial fue la más frecuente, 94,1%. Un 58,8% de los pacientes fueron revascularizados a través de la arteria radial. El 29,4% recibió el dispositivo previo a la angioplastía y 70,6% lo recibió después. El 47,1% de las angioplastías fue guiada por imágenes. En 11,8% de ellos se realizó litotricia intracoronaria y 5,9% por ablación intracoronaria. Los pacientes estuvieron 13 ±3,4 días con el soporte. La mortalidad global fue de 41,2%. Conclusiones: El uso del dispositivo Impella presentó pocas complicaciones vasculares. La mortalidad asociada con su colocación en Chile fue relativamente similar con la reportada en la literatura.

Background: Cardiogenic shock and high-risk Angioplasty are associated with a high mortality rate. Using the Impella CP device could reduce the risk of death in these scenarios. In Chile, there are no studies evaluating the use of the Impella CP device. Objective: To analyse the clinical outcomes in patients who have undergone placement of the Impella CP device for cardiogenic shock and high-risk angioplasties. Methods: A retrospective study was carried out on 17 patients, which represent the total number of implants performed in the country, between October 2021 and August 2023. The demographic, procedural and post-implant characteristics were described. Overall mortality and associated factors were identified. Results: The age was 69± 3.7 years, where 88.2% were men. 64.7% of patients received the device by SC and 35.3% by AAR. Among the comorbidities studied, arterial hypertension was the most frequent with 94.1%. 58.8% of patients were revascularized through the radial artery. 29.4% of patients received the device before angioplasty and 70.6% received it afterwards. 47.1% of angioplasties were image-guided, 11.8% had intracoronary lithotripsy, and 5.9% had intracoronary ablation. The patients spent 13 ±3.4 days with the support. Overall mortality was 41.2%. Conclusion: use of the Impella device was associated with few vascular complications. Mortality associated with use of the Impella device in Chile was similar to that previously reported in other studies.

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