20 research outputs found
Retrieval of 3D polygonal objects based on multiresolution signatures
In this paper we present a method for retrieving 3D polygonal objects by using two sets of multiresolution signatures. Both sets are based on the progressive elimination of object's details by iterative processing of the 3D meshes. The first set, with five parameters, is based on mesh smoothing. This mainly affects an object's surface. The second set, with three parameters, is based on difference volumes after successive mesh erosions and dilations. Characteristic feature vectors are constructed by combining the features at three mesh resolutions of each object. In addition to being invariant to mesh resolution, the feature vectors are invariant to translation, rotation and size of the objects. The method was tested on a set of 40 complex objects with mesh resolutions different from those used in constructing the feature vectors. By using all eight features, the average ranking rate obtained was 1.075: 37 objects were ranked first and only 3 objects were ranked second. Additional tests were carried out to determine the significance of individual features and all combinations. The same ranking rate of 1.075 can be obtained by using some combinations of only three features. © 2011 Springer-Verlag
Desarrollo tecnológico con aplicación en terapias fotodinámicas para el tratamiento de lesiones de la piel
La terapia fotodinámica es un tratamiento de primera línea para ciertas lesiones
de la piel como la queratosis actínica (QA). Con tales fines se emplean emisores de luz
con alto costo de adquisición y mantenimiento. El Departamento de Bioingeniería, del
Centro de Microscopía Electrónica de la Facultad de Ciencias Médicas, Universidad
Nacional de Córdoba (UNC), desarrolló una nueva versión de dispositivo emisor, de
bajo costo de fabricación, que emite luz pulsada intensa y es capaz de irradiar luz roja
(630 nm) y azul (405 nm). Este dispositivo es potencialmente útil en el tratamiento de
QA y carcinoma basocelular. Por otra parte el Departamento de Farmacia de la Facultad
de Ciencias Químicas, UNC, ha formulado el compuesto basado en el ácido α-
aminolevulínico (ALA) que es el precursor del agente fotosensibilizador protoporfirina
IX, habilitado por la ANMAT en presentaciones similares, y la Farmacia Central del
Hospital Nacional de Clínicas (HNC) de la UNC, efectuó la preparación del
medicamento como formulación magistral y extemporánea al 20%. Todas estas
dependencias internas de la UNC articularon en la ejecución de un proyecto de
Innovación Tecnológica, financiado por la SECYT-UNC, a los fines de completar las
etapas de desarrollo y los estudios necesarios, para poder utilizar el equipamiento y el
medicamento para terapias en el mencionado hospital. El presente trabajo aborda de
manera particular, los resultados preliminares obtenidos en el estudio clínico, realizado
en el área de Dermatología del HNC. Cabe destacar que como parte del proyecto, se
pretende la construcción en serie del dispositivo emisor a través de la Institución
Contraparte participante del proyecto, que es una reconocida empresa local fabricante
de equipamiento médico.publishedVersio
Comparison of healing of full-thickness skin wounds grafted with multidirectional or unidirectional autologous artificial dermis: differential delivery of healing biomarkers
Cytokines, chemokines, and growth and remodeling factors orchestrate wound healing when skin damage occurs. During early stages, when the wound is still open, detection and quantification of these compounds might provide biomarkers of skin wound healing, which could aid to complete the scenario provided by clinical follow-up data and histological and histomorphometric analyses. This work assessed and compared the healing of full-thickness skin wounds grafted with artificial dermis made with autologous skin fibroblasts and unidirectional or multidirectional type I collagen scaffolds to test this hypothesis. Biomarkers of healing were detected and quantified in the culture medium of artificial dermis and exudates from the grafted wounds. Clinical follow-up of animals and histological and histomorphometric analysis showed differences in graft integration, wound closure, and histological and histomorphometric parameters. Surface plasmon resonance quantification of 13 healing biomarkers indicated differential secretion of most of the quantified factors in culture medium by the multidirectional and unidirectional artificial dermis. Also, there were significant differences between the concentration of some of the factors analyzed in the exudates of wounds grafted with the evaluated artificial dermis. These findings suggest that differential delivery of healing biomarkers induced by the directionality of the scaffold used to produce the multidirectional and unidirectional dermis was sufficient to create two skin wound microenvironments that determined a different outcome of healing. Overall, data indicate that healing of wounds grafted with multidirectional autologous artificial dermis is better than that of the wounds grafted with the unidirectional one. © 2018, Controlled Release Society
Clinical evidence of magistral preparations based on medicinal cannabis
9 páginasCannabis has been widely used as a medicinal plant for millennia; however, studies related to its main components were first conducted in 1960. Subsequently, laboratories have produced new components and structures related to its active biological properties. Countries that have approved the medicinal use of cannabis impose regulations that govern its clinical and scientific use. One means of administering medicinal cannabis is via a magistral preparation that must have a medical prescription and be prepared in an establishment that meets quality standards to ensure the quantities of its main components, such as tetrahydrocannabinol (THC) and cannabidiol (CBD). Furthermore, suppliers must have a clear indication of its use in the patient before prescription. This review shows the published evidence regarding the clinical use of medicinal cannabis magistral preparations in the management of post-chemotherapy nausea and vomiting, neuropathic pain in multiple sclerosis, and anorexia and cachexia in patients with HIV
Comparison of healing of full-thickness skin wounds grafted with multidirectional or unidirectional autologous artificial dermis: differential delivery of healing biomarkers
Cytokines, chemokines, and growth and remodeling factors orchestrate wound healing when skin damage occurs. During early stages, when the wound is still open, detection and quantification of these compounds might provide biomarkers of skin wound healing, which could aid to complete the scenario provided by clinical follow-up data and histological and histomorphometric analyses. This work assessed and compared the healing of full-thickness skin wounds grafted with artificial dermis made with autologous skin fibroblasts and unidirectional or multidirectional type I collagen scaffolds to test this hypothesis. Biomarkers of healing were detected and quantified in the culture medium of artificial dermis and exudates from the grafted wounds. Clinical follow-up of animals and histological and histomorphometric analysis showed differences in graft integration, wound closure, and histological and histomorphometric parameters. Surface plasmon resonance quantification of 13 healing biomarkers indicated differential secretion of most of the quantified factors in culture medium by the multidirectional and unidirectional artificial dermis. Also, there were significant differences between the concentration of some of the factors analyzed in the exudates of wounds grafted with the evaluated artificial dermis. These findings suggest that differential delivery of healing biomarkers induced by the directionality of the scaffold used to produce the multidirectional and unidirectional dermis was sufficient to create two skin wound microenvironments that determined a different outcome of healing. Overall, data indicate that healing of wounds grafted with multidirectional autologous artificial dermis is better than that of the wounds grafted with the unidirectional one. © 2018, Controlled Release Society
Inmunogenicidad en terapias basadas en proteínas y péptidos: descripción general
15 páginasCurrently it is well known that all biological drugs, including those with a fully human structure, are capable of inducing a host immune response known as immunogenicity [1]. The presence of ADAs can condition the drug´s level and action, thus modifying the therapeutic effect and even the safety profile by its mechanism of action - neutralizing or non-neutralizing - and / or an increase in its clearance. Immunogenicity is a dynamic factor to be taken into account in biological therapy, especially in long-term treatments, and as a relevant aspect in the assessment of secondary response loss [2]. With the above, not only the knowledge but also the management of the immunogenicity of the different biological treatments, represent a useful instrument for optimization of the strategies of use for each drug, and in the design of predictive models of response, which finally permits a significant improvement in the efficacy and safety profile, aiming to a personalization of the therapies, especially in patients with autoimmune diseases, genetic disorders and cancer [3]. This review summarizes the events of immunogenicity that produce the biological drug, the factor that influence to immunogenicity and the assessment of immunogenicity.Actualmente es bien sabido que todos los fármacos biológicos, incluidos aquellos con estructura totalmente humana, son capaces de inducir una respuesta inmune del huésped conocida como inmunogenicidad [1]. La presencia de ADA puede condicionar el nivel y acción del fármaco, modificando así el efecto terapéutico e incluso el perfil de seguridad por su mecanismo de acción -neutralizante o no neutralizante- y/o un aumento en su aclaramiento. La inmunogenicidad es un factor dinámico a tener en cuenta en la terapia biológica, especialmente en tratamientos a largo plazo, y como aspecto relevante en la evaluación de la pérdida de respuesta secundaria [2]. Con lo anterior, no sólo el conocimiento sino también el manejo de la inmunogenicidad de los diferentes tratamientos biológicos, representan un instrumento útil para la optimización de las estrategias de uso de cada fármaco, y en el diseño de modelos predictivos de respuesta, lo que finalmente permite una mejora significativa en el perfil de eficacia y seguridad, con el objetivo de personalizar las terapias, especialmente en pacientes con enfermedades autoinmunes, trastornos genéticos y cáncer [3]. Esta revisión resume los eventos de inmunogenicidad que produce el fármaco biológico, los factores que influyen en la inmunogenicidad y la evaluación de la inmunogenicidad
Immunogenicity in Protein and Peptide Based-Therapeutics: An Overview
15 páginasCurrently it is well known that all biological drugs, including those with a fully human structure, are capable of inducing a host immune response known as immunogenicity [1]. The presence of ADAs can condition the drug´s level and action, thus modifying the therapeutic effect and even the safety profile by its mechanism of action - neutralizing or non-neutralizing - and / or an increase in its clearance. Immunogenicity is a dynamic factor to be taken into account in biological therapy, especially in long-term treatments, and as a relevant aspect in the assessment of secondary response loss [2]. With the above, not only the knowledge but also the management of the immunogenicity of the different biological treatments, represent a useful instrument for optimization of the strategies of use for each drug, and in the design of predictive models of response, which finally permits a significant improvement in the efficacy and safety profile, aiming to a personalization of the therapies, especially in patients with autoimmune diseases, genetic disorders and cancer [3]. This review summarizes the events of immunogenicity that produce the biological drug, the factor that influence to immunogenicity and the assessment of immunogenicity.Actualmente es bien sabido que todos los fármacos biológicos, incluidos aquellos con estructura totalmente humana, son capaces de inducir una respuesta inmune del huésped conocida como inmunogenicidad [1]. La presencia de ADA puede condicionar el nivel y acción del fármaco, modificando así el efecto terapéutico e incluso el perfil de seguridad por su mecanismo de acción -neutralizante o no neutralizante- y/o un aumento en su aclaramiento. La inmunogenicidad es un factor dinámico a tener en cuenta en la terapia biológica, especialmente en tratamientos a largo plazo, y como aspecto relevante en la evaluación de la pérdida de respuesta secundaria [2]. Con lo anterior, no sólo el conocimiento sino también el manejo de la inmunogenicidad de los diferentes tratamientos biológicos, representan un instrumento útil para la optimización de las estrategias de uso de cada fármaco, y en el diseño de modelos predictivos de respuesta, lo que finalmente permite una mejora significativa en el perfil de eficacia y seguridad, con el objetivo de personalizar las terapias, especialmente en pacientes con enfermedades autoinmunes, trastornos genéticos y cáncer [3]. Esta revisión resume los eventos de inmunogenicidad que produce el fármaco biológico, los factores que influyen en la inmunogenicidad y la evaluación de la inmunogenicidad
Validación del Puntaje Nacional de Alerta Temprana (NEWS)-2 para adultos en el servicio de urgencias de una clínica de tercer nivel en Colombia
8 páginasThe National Early Warning Score (NEWS)-2 is an early warning scale that is used in emergency departments to identify patients at risk of clinical deterioration and to help establish rapid and timely management. The objective of this study was to determine the validity and prediction of mortality using the NEWS2 scale for adults in the emergency department of a tertiary clinic in Colombia.
A prospective observational study was conducted between August 2018 and June 2019 at the Universidad de La Sabana Clinic.
The nursing staff in the triage classified the patients admitted to the emergency room according to Emergency Severity Index and NEWS2. Demographic data, physiological variables, admission diagnosis, mortality outcome, and comorbidities were extracted.
Three thousand nine hundred eighty-six patients were included in the study. Ninety-two (2%) patients required intensive care unit management, with a mean NEWS2 score of 7. A total of 158 patients died in hospital, of which 63 were women (40%). Of these 65 patients required intensive care unit management. The receiver operating characteristic curve for NEWS2 had an area of 0.90 (CI 95%: 0.87–0.92). A classification and score equivalency analysis was performed between triage and the NEWS2 scale in terms of mortality. Of the patients classified as triage I, 32.3% died, and those who obtained a NEWS2 score greater than or equal to 10 had a mortality of 38.6%.
Among our population, NEWS2 was not inferior in its area under the receiver operating characteristic curve when predicting mortality than triage, and the cutoff point for NEWS2 to predict in-hospital mortality was higher
Indexing Dense Nested Metric Spaces for Efficient Similarity Search ⋆
Abstract. Searching in metric spaces is a very active field since it offers methods for indexing and searching by similarity in collections of unstructured data. These methods select some objects of the collection as reference objects to build the indexes. It has been shown that the way the references are selected affects the search performance, and several algorithms for good reference selection have been proposed. Most of them assume the space to have a reasonably regular distribution. However, in some spaces the objects are grouped in small dense clusters that can make these methods perform worse than a random selection. In this paper, we propose a new method able to detect these situations and adapt the structure of the index to them. Our experimental evaluation shows that our proposal is more efficient than previous approaches when using the same amount of memory.