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Low-cost sensors to detect cancer biomarkers with high sensitivity and selectivity are essential for early diagnosis. Herein, an immunosensor was developed to detect the cancer biomarker p53 antigen in MCF7 lysates using electrical impedance spectroscopy. Interdigitated electrodes were screen printed on bacterial nanocellulose substrates, then coated with a matrix of layer-by-layer films of chitosan and chondroitin sulfate onto which a layer of anti-p53 antibodies was adsorbed. The immunosensing performance was optimized with a 3-bilayer matrix, with detection of p53 in MCF7 cell lysates at concentrations between 0.01 and 1000 Ucell. mL-1, and detection limit of 0.16 Ucell mL-1. The effective buildup of the immunosensor on bacterial nanocellulose was confirmed with polarization-modulated infrared reflection absorption spectroscopy (PM-IRRAS) and surface energy analysis. In spite of the high sensitivity, full selectivity with distinction of the p53-containing cell lysates and possible interferents required treating the data with a supervised machine learning approach based on decision trees. This allowed the creation of a multidimensional calibration space with 11 dimensions (frequencies used to generate decision tree rules), with which the classification of the p53-containing samples can be explained.

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Mass testing for the diagnostics of COVID-19 has been hampered in many countries owing to the high cost of the methodologies to detect genetic material of SARS-CoV-2. In this paper, we report on a low-cost immunosensor capable of detecting the spike protein of SARS-CoV-2, including in samples of inactivated virus. Detection is performed with electrical impedance spectroscopy using an immunosensor that contains a monolayer film of carboxymethyl chitosan as matrix, coated with an active layer of antibodies specific to the spike protein. In addition to a low limit of detection of 0.179 fg/mL within an almost linear behavior from 10-20 g/mL to 10-14 g/mL, the immunosensor was highly selective. For the samples with the spike protein could be distinguished in multidimensional projection plots from samples with other biomarkers and analytes that could be interfering species for healthy and infected patients. The excellent analytical performance of the immunosensors was validated with the distinction between control samples and those containing inactivated SARS-CoV-2 at different concentrations. The mechanism behind the immunosensor performance is the specific antibody-protein interaction, as confirmed with the changes induced in C-H stretching and protein bands in polarization-modulated infrared reflection absorption spectra (PM-IRRAS). Because impedance spectroscopy measurements can be made with low-cost portable instruments, the immunosensor proposed here can be applied in point-of-care diagnostics for mass testing even in places with limited resources.

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We designed an infographic intervention to help clinicians provide health information to persons living with HIV. In this study, we assessed the extent to which our intervention may improve objectively and subjectively measured health outcomes (CD4 count, viral load, and engagement with clinician among others) when integrated into routine visits in the Dominican Republic. In this pretest-posttest study, we followed participants for 9 months at 3-month intervals. Physicians administered the intervention during participants' first 3 visits. Outcome measures, selected using a conceptual model, were assessed at 4 time points. We assessed changes in outcomes over time with general linear regressions and Wilcoxon Signed-Rank tests. Participants (N = 50) were mostly female (56%) and had been living with HIV for a mean of 6.3 years (SD = 6.1). All outcomes, except CD4 count, demonstrated statistically significant improvements by study end. This provides preliminary evidence our intervention may improve outcomes, but further testing is needed.

RESUMEN: Diseñamos una intervención infográfica para ayudar a los médicos brindar información médica a personas viviendo con el VIH. En este estudio, evaluamos en qué medida nuestra intervención puede mejorar los resultados de salud (conteo de CD4, carga viral, y compromiso con el médico entre otros), medidos de una manera objetiva y subjetiva, cuando se incorpora en las visitas médicas de rutina en la República Dominicana. En este estudio de prueba previo y posterior, seguimos los participantes durante 9 meses a intervalos de 3 meses. Los médicos administraron la intervención durante las primeras 3 visitas de los participantes. Seleccionamos las medidas de resultado utilizando un marco conceptual y las evaluamos en los 4 puntos de tiempo. Evaluamos cambios a lo largo del tiempo usando regresiones lineales generales y pruebas de asociación de Wilcoxon Signed-Rank. Los participantes (N = 50) fueron mayormente mujeres (56%) y habían estado viviendo con el VIH durante una media de 6,3 años (DE = 6,1). Todos los resultados, aparte del conteo de CD4, demostraron mejoras estadísticamente significativas al final del estudio. Esto proporciona evidencia preliminar de que nuestra intervención puede mejorar los resultados de la salud, pero se justifican pruebas adicionales.

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El estudio tuvo como objetivo examinar la viabilidad de la aplication de herramientas que ilustren el uso de la colección y de la institución, por parte la comunidad usuaria de la Biblioteca Provincial Martí, y contribuyan a una mejor toma de decisiones. La investigación se basó en una combinación de métodos cualitativos y cuantitativos; entre ellos, los matemáticos y estadísticos y las herramientas de visualización de la información. La muestra comprendió 1 422 usuarios, representativa del 25 por ciento del total de la población de la Biblioteca Provincial Martí, de Villa Clara. A partir de la información que se generó en el sistema de control estadístico de la institución, se recolectaron, se procesaron y se analizaron indicadores relativos al índice de captación, los servicios por usuarios, el uso de la biblioteca, el índice de circulación de la colección, el índice de rotación de la colección y el co-uso de los documentos por temáticas. Los datos revelaron aspectos esenciales de la gestión de la institución objeto de estudio y la necesidad de acometer acciones con respecto a su política de adquisición y de difusión, a fin de revertir los aspectos con incidencia negativa. El trabajo concluye con el reconocimiento de que la aplicación de esta novedosa forma de tratar los datos es una alternativa para la presentación de información en el proceso de la toma de decisiones de cualquier institución similar(AU)

The purpose of the study was to examine the viability of the application of tools that illustrate the use of the collection and the institution, by the user community of the Martí Provincial Library, which contributes to better decision-making.The research was based on a combination of qualitative and quantitative methods, among them mathematical and statistical, and information visualization tools. The sample was composed of 1 422 users representing 25 percent of the total population of Martí Provincial Library in Villa Clara. Starting from the information generated by the statistical control system of the institution, indicators were collected, processed and analyzed which had to do with the following variables: recruitment rate, services per user, use of the library, collection circulation rate, collection turnover rate, and document co-use by subject. The data revealed essential aspects of management at the study institution, as well as the need to implement actions related to their acquisition and dissemination policy with a view to improving deficient areas. The paper recognizes that application of this novel way to treat data is an alternative for the presentation of information in the decision-making process at any similar institution(AU)

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The increasing need for point-of-care diagnosis has sparked the development of label-free sensing platforms, some of which are based on impedance measurements with biological cells. Here, interdigitated electrodes were functionalized with layer-by-layer (LbL) films of hyaluronan (HA) and chitosan (CHI) to detect prostatic tumor cells (PC3 line). The deposition of LbL films was confirmed with atomic force microscopy and polarization-modulated infrared reflection absorption spectroscopy (PM-IRRAS), which featured the vibrational modes of the HA top layer capable of interacting specifically with glycoprotein CD44 receptors overexpressed in tumor cells. Though the CHI/HA LbL films cannot be considered as a traditional biosensor due to their limited selectivity, it was possible to distinguish prostate tumor cells in the range from 50 to 600 cells/µL in in vitro experiments with impedance spectroscopy. This was achieved by treating the impedance data with information visualization methods, which confirmed the distinguishing ability of the films by observing the absence of false positives in a series of control experiments. The CD44-HA interactions may, therefore, be exploited in clinical analyses and point-of-care diagnostics for cancer, particularly if computational methods are used to process the data.

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Comparison of hierarchies aims at identifying differences and similarities between two or more hierarchical structures. In the biological taxonomy domain, comparison is indispensable for the reconciliation of alternative versions of a taxonomic classification. Biological taxonomies are knowledge structures that may include large amounts of nodes (taxa), which are typically maintained manually. We present the results of a user study with taxonomy experts that evaluates four well-known methods for the comparison of two hierarchies, namely, edge drawing, matrix representation, animation and agglomeration. Each of these methods is evaluated with respect to seven typical biological taxonomy curation tasks. To this end, we designed an interactive software environment through which expert taxonomists performed exercises representative of the considered tasks. We evaluated participants' effectiveness and level of satisfaction from both quantitative and qualitative perspectives. Overall quantitative results evidence that participants were less effective with agglomeration whereas they were more satisfied with edge drawing. Qualitative findings reveal a greater preference among participants for the edge drawing method. In addition, from the qualitative analysis, we obtained insights that contribute to explain the differences between the methods and provide directions for future research.

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Diagnosis of cancer using electroanalytical methods can be achieved at low cost and in rapid assays, but this may require the combination with data treatment for determining biomarkers in real samples. In this paper, we report an immunomagnetic nanoparticle-based microfluidic sensor (INµ-SPCE) for the amperometric detection of the prostate-specific antigen (PSA) biomarker, the data of which were treated with information visualization methods. The INµ-SPCE consists of eight working electrodes, reference and counter electrodes. On the working electrodes, magnetic nanoparticles with secondary antibodies with the enzyme horseradish peroxidase were immobilized for the indirect detection of PSA in a sandwich-type procedure. Under optimal conditions, the immunosensor could operate within a wide range from 12.5 to 1111 fg·L-1, with a low detection limit of 0.062 fg·L-1. Multidimensional projections combined with feature selection allowed for the distinction of cell lysates with different levels of PSA, in agreement with results from the traditional enzyme-linked immunosorbent assay. The approaches for immunoassays and data processing are generic, and therefore the strategies described here may provide a simple platform for clinical diagnosis of cancers and other types of diseases.

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Nanostructured capacitive biosensors, combined with inexpensive fabrication technologies, may provide simple, sensitive devices for detecting clinically relevant cancer biomarkers. Herein, we report a novel platform for detecting the pancreatic cancer biomarker CA19-9 using low-cost screen-printed interdigitated electrodes (SPIDEs). The SPIDEs were modified by carbon nano-onions (CNOs) and graphene oxide (GO) films, on which a layer of anti-CA19-9 antibodies was immobilized. The modification with CNOs and GO significantly improved the analytical performance of the biosensor, which displayed superior results to those prepared only with GO. The biossensor exhibited high reproducibility and a relatively low limit of detection of 0.12 U mL-1. Using these devices in combination with information visualization methods we were able to detect CA19-9 in whole cell lysates of colorectal adenocarcinoma. The fabrication of these low-cost, disposable immunosensors is a successful attempt to explore CNOs in capacitive biosensors, which may be extended for detection of different cancer biomarkers.

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Este estudio analiza la evolución de la estructura conceptual en el campo de las Experiencias Adversas en la Infancia desde el año 1994 al 2017, así como la productividad y la calidad alcanzada en seis períodos, y particularmente en la fase actual. Para esto, se realizó un mapeo bibliométrico basado en los artículos científicos referidos al área, indexados en la colección principal de la Web of Science. Mediante el análisis de términos se construyeron redes en un marco longitudinal, lo que permitió la identificación de temas principales y los nexos entre estos. Los resultados obtenidos permiten concluir que las Experiencias Adversas en la Infancia son un dominio de estudio relativamente nuevo, con un aumento sostenido en el volumen de artículos desde el período 1998-2001 al 2017 y un impacto creciente desde el año 1998 al 2013. El aumento en el volumen y el impacto de las publicaciones se relaciona con la progresiva complejización temática del campo, el cual evoluciona como conjunto y ha adquirido estabilidad en el período 1998-2001. En la actualidad, el área cuenta con un importante volumen de producción e impacto concentrado en sus temas motores (Experiencias Adversas en la Infancia, Factores de Riesgo y Violencia). Salud Física figura como principal núcleo del área básica y transversal, mientras que Disparidades Racial-Étnicas constituyen un tema principal desarrollado, pero aislado. Será necesario esperar a constatar la evolución del campo para asegurar si Resiliencia, y Embarazo y Posparto emergen para consolidarse como núcleos, o pierden su capacidad para aglutinar a otros nodos del área(AU)

The study examines the evolution of the conceptual structure in the field of the Adverse Childhood Experiences from 1994 to 2017, as well as the productivity and quality achieved in six periods, and particularly in the current stage. Bibliometric mapping was conducted based on scientific papers about the subject indexed in the main collection of the Web of Science. Analysis of terms led to the building of networks in a longitudinal frame, allowing identification of the main topics and the links between them. The results obtained allow to conclude that Adverse Childhood Experiences is a relatively new study domain, with a sustained increase in the number of papers from the 1998-2001 period to 2017 and a growing impact from 1998 to 2013. Increase in the number and impact of publications is related to the growing thematic complexity of the field, which evolves as a whole and has gained stability since the 1998-2001 period. Today, the area exhibits significant production and impact, particularly in its core themes (Adverse Childhood Experiences, Risk Factors and Violence). Physical Health is the main core in the basic and cross-sectional area, whereas Racial-Ethnic Disparities is a main topic developed, but isolated. Time is required to watch the evolution of the field and verify whether Resilience, and Pregnancy and Postpartum either become core themes, or lose their ability to bind to other nodes in the area(AU)

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The fast growth of celiac disease diagnosis has sparked the production of gluten-free food and the search for reliable methods to detect gluten in foodstuff. In this paper, we report on a microfluidic electronic tongue (e-tongue) capable of detecting trace amounts of gliadin, a protein of gluten, down to 0.005 mg kg-1 in ethanol solutions, and distinguishing between gluten-free and gluten-containing foodstuff. In some cases, it is even possible to determine whether gluten-free foodstuff has been contaminated with gliadin. That was made possible with an e-tongue comprising four sensing units, three of which made of layer-by-layer (LbL) films of semiconducting polymers deposited onto gold interdigitated electrodes placed inside microchannels. Impedance spectroscopy was employed as the principle of detection, and the electrical capacitance data collected with the e-tongue were treated with information visualization techniques with feature selection for optimizing performance. The sensing units are disposable to avoid cross-contamination as gliadin adsorbs irreversibly onto the LbL films according to polarization-modulated infrared reflection absorption spectroscopy (PM-IRRAS) analysis. Small amounts of material are required to produce the nanostructured films, however, and the e-tongue methodology is promising for low-cost, reliable detection of gliadin and other gluten constituents in foodstuff.

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