Search

Introducción: La Facultad de Ciencias de la Universidad Mayor utiliza regularmente pruebas de opción múltiple (POM) en la evaluación del aprendizaje en estudiantes de pregrado. Desde hace 10 años estas pruebas son corregidas con sistemas automáticos; esto permitió generar un diagnóstico global de las POM utilizadas. Objetivo: Analizar el índice de dificultad, el de discriminación, el coeficiente de fiabilidad y los distractores de las POM aplicadas en las distintas carreras de la salud y corregidas de manera automatizada y centralizada en la Facultad de Ciencias de la Universidad Mayor, en el periodo 2013-2017. Método: Para este estudio cuantitativo, descriptivo, no experimental, transversal y retrospectivo, de 2,640 pruebas corregidas por lector óptico, aplicadas por 7 carreras de la salud, se seleccionaron aleatoriamente 337 por muestreo probabilístico estratificado con selección sistemática. Se estimaron indicadores psicométricos en el marco de la Teoría Clásica de Test y se utilizó el test de ANOVA para la comparación entre carreras. Resultados: Los índices de dificultad, de discriminación y el coeficiente de fiabilidad presentan promedios de 68%, 0.23 y 0.50 respectivamente. Se observaron diferencias significativas entre carreras en los índices de dificultad y discriminación. En relación a los distractores en promedio, 1.51 distractores son funcionales (1.52 para preguntas de cuatro alternativas, y 1.49 para preguntas de cinco alternativas). Conclusiones: Los resultados develan situaciones críticas en evaluación de los aprendizajes, que demandan profundizar la reflexión de directivos y docentes de las distintas carreras para asegurar la validez y calidad de las POM.

El presente artículo tiene como finalidad realizar el análisis de la política de inclusión educativa en el Ecuador y su relación con el accionar pedagógico vigente en los escenarios educativos. Los sistemas educativos del estado ecuatoriano a pesar de estar alineados a parámetros internacionales de inclusión, no ha superado la brecha de discriminación a las personas con necesidades educativas especiales (NEE). El presente documento aporta principalmente a la innovación en el pensamiento pedagógico de los docentes, para ello, parte del informe de Warnock (documento que fue elaborado por la Comisión de Educación británica) el mismo que revoluciona en la forma de pensar de todos cuando revela que “no existen niños ineducables” (Warnock, 1987, p. 15). La metodología utilizada en la estructuración de este trabajo es de carácter inductiva – deductiva y se apoya en la investigación bibliográfica. Los resultados del presente estudio revelan falencias y dificultades en la inclusión educativa de estudiantes con NEE, los problemas más relevantes que se observaron fueron las deficiencias conceptuales en torno a inclusión educativa, escaso conocimiento sobre un currículo inclusivo y debilidades en una supuesta homogeneidad en el aula. Este documento presenta brevemente algunas perspectivas y desafíos para promover un pensamiento inclusivo pero, sobre todo, abierto a la diversidad.

Background: the incidence of lung cancer in the province of Sancti Spíritus is high and its diagnosis is usually made in advanced stages, for which surgical treatment is not always possible. Objective: to analyze the main characteristics and results of patients operated on for lung cancer. Methods: a cross-sectional descriptive observational study was carried out in the General Surgery service of the Camilo Cienfuegos General University Hospital in the Sancti Spiritus province in the period between January 1996 and December 2019. The universe consisted of 83 patients operated with lung cancer who underwent resection accompanied by mediastinal lymph node sampling. Results: the male sex predominated in the studied group. The most frequent age groups for both sexes were those from 51 to 60 years old and those over 60 years old. Smoking was present in most of the patients. The most frequent tumor location was in the upper lobes and lobectomy was the most performed technique. The pathological stages that predominated were lB and llB, followed by lllA. Squamous cell carcinoma was the predominant histological type. Atelectasis and respiratory infections were the most frequent complications. The deceased were few. Conclusions: the demographic characteristics of the patients studied correspond to other series of patients with lung cancer. Tumor location in the upper lobes, squamous cell carcinoma, as well as early stages, predominated in the series studied. Lobectomy was the most frequently used surgical technique and among complications, respiratory ones were the most frequent. DeCS: LUNG NEOPLASMS/surgery; LUNG NEOPLASMS/diagnosis; LUNG NEOPLASMS/complications; PNEUMONECTOMY/methods; CARCINOMA, SQUAMOUS CELL/complications.

Surgery of the cervical spine under conscious sedation has been rarely reported in the literature. The main indications are the lack of neurophysiological monitoring and surgery in patients with high cardiovascular risk. To date, no reports of awake C1–2 instrumentation have been published in the English-language literature. The authors present the case of a 76-year-old patient with multiple myeloma and severe cardiomyopathy associated with primary amyloidosis who experienced severe myelopathy from a C2 pseudotumor associated with an odontoid fracture. Due to his high cardiovascular risk, the patient underwent C1 decompression and C1–2 instrumentation and fusion via an awake technique. To accomplish this task, the authors performed multilayered muscular infiltration of local anesthetics and avoided manipulating the C2 root by anchoring C1 with a rod-claw system. The procedure did not last longer than that of general anesthetic approaches, and no complaints were reported by the patient during surgery, which he described as an overall “good experience.” The patient was discharged on the 7th postoperative day and resumed his previous work 3 months later. Performing surgery under local anesthesia and conscious sedation reduces the risk of perioperative cardiovascular and respiratory complications in these high-risk patients by avoiding the use of drugs with cardiodepressant effects and endotracheal intubation.

espanolIntroduccion: Mucina1 (MUC1) es una glicoproteina transmembrana normalmente expresada en la cara apical de muchas celulas epiteliales secretoras. MUC1 es sobreexpresada en diversos carcinomas, siendo considerada como sensor molecular y transductor de senales en respuestas a estimulos externos. Sin embargo, el significado de esta sobreexpresion en celulas tumorales, asi como su papel en CBC, aun no han sido determinados. Objetivos: Investigar por metodos inmunohistoquimicos si MUC1 esta presente en los engrosamientos epidermicos observados en CBC superficial. Examinar la presencia y localizacion de NFκBp65, NFκBp50, c-Src, EGFR y ErbB2 en sus formas activadas en algunas de esas biopsias. Metodologia: Ocho biopsias de pacientes diagnosticados con CBC superficial fueron seleccionadas. Seis muestras de piel normal tambien fueron examinadas. La presencia y distribucion de esas proteinas fue evaluada por inmunofluorescencia con un microscopio confocal. Resultados: La inmunotincion revelo que MUC1 estaba presente en los engrosamientos epidermicos de todas las biopsias examinadas. Tambien demostro que las formas activadas de NFκBp65, NFκBp50, IKKα/β y c-Src estaban presentes en los engrosamientos donde MUC1 fue detectada. Adicionalmente, mostramos que las formas activadas de EGFR y ErbB2 estaban localizadas en el nucleo de muchas de las celulas. Conclusiones: Basados en nuestras observaciones y estudios previos, proponemos que la estimulacion de los queratinocitos (por exposicion a las radiaciones UV, dano mecanico, factores de crecimiento o citocinas) podria activar a aquellas moleculas como c-Src e IKKα que favorecen la translocacion de NFκB y la eventual expresion de MUC1. Una vez expresada, MUC1 estaria participando en algunas respuestas celulares como la proliferacion, perdida de las uniones intercelulares, migracion y supervivencia de los queratinocitos. EnglishIntroduction: Mucin1 (MUC1) is a transmembrane glycoprotein normally expressed on the apical side of many secretory epithelial cells. It is overexpressed in many carcinomas being considered as molecular sensor and signal transducer in response to external stimuli. However, its possible role in CBC has not been considered. Aim: To ascertain whether MUC1 is present in the epidermal thickening of CBC superficial. Also, to examine the presence and location of NFκBp65, NFκBp50, c- Src, EGFR and ErbB2 in their activated forms in some of these biopsies. Methodology: Eight biopsies of patients diagnosed with superficial BCC were selected. Six samples of normal skin were also examined. The presence of these proteins was assessed by immunofluorescence with a confocal microscope. Results: Immunostaining revealed that MUC1 was present in the epidermal thickening of all biopsies examined. Also, demonstrated that the activated forms of NFκBp65, NFκBp50, IKKα/β, and c-Src were present in these thickened where MUC1 was detected. Additionally, we show that the activated forms of EGFR and ErbB2 were located in the nucleus of many of the thickened epidermal cells. Conclusions: Based on our observations and previous studies, we propose that the stimulation of keratinocytes (by exposure to UV radiation, mechanical damage, growth factors or cytokines) may enable those molecules such as c-Src and IKKα favoring the activation of NFκβ and the eventual expression of MUC1. Once expressed MUC1 would be participating in some cellular responses such as cell proliferation, loss of intercellular junctions, migration and survival of keratinocytes.

Background Dobutamine is particularly suited to treatment of haemodynamic insufficiency caused by increased peripheral vascular resistance and myocardial dysfunction in the preterm infant. Knowledge of the elimination half-life is essential to estimate the steady state when its efficacy/safety can be evaluated. Methods Analysis of pharmacokinetic data in ten preterm newborns treated with a new neonatal formulation of dobutamine (IMP) after screening for haemodynamic insufficiency within the first 72 h from birth. Blood samples were withdrawn at the end of IMP infusion and at a random time after the end of infusion (5 min, 15 min, 45 min, 2 h and 6 h). IMP concentration in each sample was measured by ultra-high performance liquid chromatography with electrochemical detection. Results Median duration of IMP infusion was 37.7 h (IQR 21.2). Calculated IMP half-life ranged between 3.06 and 36.1 min (median 10.6 min), leading to a time to reach the steady-state concentration between 15 min and >2 h. Adverse events were not related to IMP. Conclusions The wide variability in dobutamine metabolism in preterm infants requires awareness about the risk of under- or overtreatment. A delay of up to 3 h might be required before drawing blood samples to evaluate the effective dose. Impact Small trials suggest dobutamine as the optimal drug in the preterm infant with haemodynamic insufficiency after birth.Age-related differences in drug pharmacokinetics may result in suboptimal treatments.The lack of formal studies in preterms results in inadequate data on efficacy and safety.This study provides data on the variability of the elimination half-life of dobutamine in the very preterm infant during transitional circulation.There is a wide variation in the time to reach the plasma concentration corresponding to steady state, the moment when its efficacy/safety can be reliably evaluated.This information is crucial for planning future trials on cardiovascular support.

Introduction:Pyogenic granuloma (PG) is a reactive inflammatory vascular lesion of the skin and mucous membranes, characterised by the presence of enlarged venules and seamed and seamless capillaries with plump endothelial cells (EC), and numerous macrophages. EC activation upregulates the synthesis of galectins and induces their translocation to the EC surface promoting angiogenesis and lymphangiogenesis, particularly galectin-1 (Gal-1), Gal-3 and Gal-8. However, the presence and distribution of Gal-1, -3 and -8, as well as their implications in the pathogenesis of PG, has not been considered.Materials and methods:Eight biopsies from patients diagnosed with PG were selected. The presence of PECAM-1/CD31, IL-1β, VEGF-C, VEGFR-2, VEGFR-3, integrin β1, CD44, fibronectin and Gal-1, -3 and -8 was assessed by immunofluorescence staining using confocal laser scanning microscopy.Results and Discussion:Immunostaining revealed that these molecules were present in the enlarged venules with plump ECs, in some macrophages and other immune cells. We propose that macrophages release VEGF-A and VEGF-C inducing VEGFR-2/VEGFR-3 expression and activation, leading macrophages to transdifferentiate into plump ECs that might integrate into pre-existing venules, contributing to the formation of enlarged venules with transluminal bridges and capillaries. EC activation, induced by certain cytokines, has been shown to stimulate galectin expression and changes in the cellular localisation through association and activation of specific EC surface glycoproteins. Therefore, it is plausible that Gal-1, -3 and -8, acting in a concerted manner, could be mediating the transdifferentiation of macrophages into plump ECs and facilitating their migration and incorporation into the new vessels.Lay SummaryIn this study, immunostaining of pyogenic granuloma (PG) tissue sections showed immunoreactivity for PECAM-1/CD31, IL-1β, VEGF-C, VEGFR-2 and VEGFR-3, and galectin-1, -3 and -8 in enlarged venules with plump endothelial cells (EC), as well as in some macrophages and other immune cells. Interestingly, enlarged and thin-walled transient vessels lined by PECAM-1/CD31 and VEGFR-2 immunopositive ECs that form from pre-existing normal venules in response to VEGF-A (called ‘mother’ vessels [MV]) and that undergo intraluminal bridging evolving into various types of capillaries (called ‘daughter’ vessels [DV]) have been observed in benign and malignant tumours, in physiological and pathological angiogenesis as well as in vascular malformations, suggesting an important role for VEGF-A and VEGFR-2 in such a process. However, it is not only the mechanisms by which the MVs evolve in different types of DVs that remains to be elucidated, but also whether the cells that form intraluminal bridges proceed from locally activated ECs or whether they are derived from bone marrow precursors or from resident macrophages. Given that the formation of homodimers by Gal-1 and Gal-8 and pentamers by Gal-3 to generate gal–glycan lattices at the cell surface and in the extracellular space has been shown, it is possible that in PG tissue Gal-1, -3 and -8, through their binding partners, form a supramolecular structure at the surface of ECs and plump ECs, macrophages and in the extracellular space that might be mediating the transdifferentiation of macrophages into plump ECs and facilitating the migration and incorporation of these cells into the pre-existing venules, thus contributing to the formation of MVs and DVs.

Dobutamine is particularly suited to treatment of haemodynamic insufficiency caused by increased peripheral vascular resistance and myocardial dysfunction in the preterm infant. Knowledge of the elimination half-life is essential to estimate the steady state when its efficacy/safety can be evaluated.Analysis of pharmacokinetic data in ten preterm newborns treated with a new neonatal formulation of dobutamine (IMP) after screening for haemodynamic insufficiency within the first 72 h from birth. Blood samples were withdrawn at the end of IMP infusion and at a random time after the end of infusion (5 min, 15 min, 45 min, 2 h and 6 h). IMP concentration in each sample was measured by ultra-high performance liquid chromatography with electrochemical detection.Median duration of IMP infusion was 37.7 h (IQR 21.2). Calculated IMP half-life ranged between 3.06 and 36.1 min (median 10.6 min), leading to a time to reach the steady-state concentration between 15 min and2 h. Adverse events were not related to IMP.The wide variability in dobutamine metabolism in preterm infants requires awareness about the risk of under- or overtreatment. A delay of up to 3 h might be required before drawing blood samples to evaluate the effective dose.Small trials suggest dobutamine as the optimal drug in the preterm infant with haemodynamic insufficiency after birth. Age-related differences in drug pharmacokinetics may result in suboptimal treatments. The lack of formal studies in preterms results in inadequate data on efficacy and safety. This study provides data on the variability of the elimination half-life of dobutamine in the very preterm infant during transitional circulation. There is a wide variation in the time to reach the plasma concentration corresponding to steady state, the moment when its efficacy/safety can be reliably evaluated. This information is crucial for planning future trials on cardiovascular support.

Collapsin Response Mediator Protein 2 (CRMP2) is an intracellular protein involved in axon and dendrite growth and specification. In this study, CRMP2 was identified in a conditioned media derived from degenerated sciatic nerves (CM). On cultured rat hippocampal neurons, acute extracellular application of CM or partially purified recombinant CRMP2 produced an increase in cytoplasmic calcium. The increase in cytoplasmic calcium was mostly mediated through NMDA receptors, with a minor contribution of N-type VDCC, and it was maintained as long as CM was present. By using live-labeling of CRMP2, Ca2+ channel binding domain 3 (CBD3) peptide derived from CRMP2, and recombinant CRMP2, we demonstrated that that this effect was mediated by an action on the extracellular side of the NMDA receptor. This is the first report of an extracellular action of CRMP2. Prolonged exposure to extracellular CRMP2, may contribute to neuronal calcium dysregulation and neuronal damage. Fil: Castillo Soto, Francisca Cecilia. Instituto de Estudios Avanzados ; Venezuela Fil: Martinez Rozas, Juan Carlos. Instituto de Estudios Avanzados ; Venezuela Fil: Longart, Marines. Instituto de Estudios Avanzados ; Venezuela Fil: García, Lisbeth. Instituto de Estudios Avanzados ; Venezuela Fil: Hernández, Marianela. Instituto de Estudios Avanzados ; Venezuela Fil: Carballo, Jeismar. Instituto de Estudios Avanzados ; Venezuela Fil: Rojas, Héctor Gustavo. Universidad Central de Venezuela. Facultad de Medicina; Venezuela Fil: Matteo, Lorena Romina. Instituto de Estudios Avanzados ; Venezuela Fil: Casique, Liliana. Universidad Simon Bolivar.; Venezuela Fil: Escalona Hernández, José Leonardo. Universidad Simon Bolivar.; Venezuela Fil: Rodríguez, Yuryanni. Instituto de Estudios Avanzados ; Venezuela Fil: Rodríguez Durán, Jessica Jenireth. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto de Estudios Avanzados ; Venezuela Fil: Hernández, Deyanell. Instituto de Estudios Avanzados ; Venezuela Fil: Balbi, Domingo. Instituto de Estudios Avanzados ; Venezuela Fil: Villegas, Raimundo. Instituto de Estudios Avanzados ; Venezuela

Purpose. Multiple Helicobacter pylori strains colonize and coexist in the stomach of one single patient, carrying heterogeneous distributions of cag genotypes. The oesophagus provides a niche for H. pylori colonization; however, little is known about its adaptive role. Methodology. Using PCR for cagA, cagE and virB11 genes from cag-pathogenicity island (PAI) and Etest for antimicrobial susceptibility test, we determined cag-PAI genotypes associated with H. pylori virulence, when positive cultures were matching in both the stomach and the oesophagus (96 isolates; 8 out of 80 dyspeptic patients). Results. The stomach showed complete cag-PAI islands in 77 % of the isolates, whereas the oesophagus showed complete cag-PAI islands only in 44 % of the isolates. Expression of CagA and interleukin 8 correlated with inflammatory processes and histopathological changes in the stomach, but not in the oesophagus. Different cag-PAI profiles were found in both mucosae of an individual host, and at least one oesophagus profile corresponded to one profile identified in stomach. The antibiotic resistance profiles showed variability in the colonization by single or mixed H. pylori isolates in the gastric and oesophageal mucosa both intra- and inter-individuals. Conclusion. These results demonstrate colonization with multiple H. pylori isolates in the oesophageal mucosa, like those found in the stomach of individual hosts. H. pylori was characterized by a dominant partial island, low interleukin 8 induction with lower histopathological damage and lower antibiotic resistance, suggesting that the microenvironmental changes in individual hosts select less virulent isolates in the oesophagus than in the stomach. New approaches to ensure effective eradication therapy in multi-resistant H. pylori strains must be developed.

Fundamentación: En la provincia Sancti Spíritus no se reportan estudios sobre la supervivencia de pacientes con cáncer de pulmón sometidos a cirugía de resección con linfoadenectomía por muestreo. Objetivo: Evaluar la supervivencia de los pacientes con cáncer de pulmón sometidos a cirugía de resección pulmonar y linfadenectomía por muestreo. Metodología: Se realizó una investigación retrospectiva en el Hospital Provincial General Camilo Cienfuegos de Sancti Spíritus, desde el 1 de enero del 1996 al 31 de diciembre del 2007. Fueron incluidos 48 pacientes a los que se les realizó cirugía de resección pulmonar con linfadenectomía por muestreo. Como variable principal fue considerada la supervivencia global a los 5 y 10 años. Otras variables fueron: edad, sexo, clasificación histológica y estadio patológico del tumor primario. Resultados: Predominaron los pacientes del sexo masculino, los mayores de 50 años y con estadio patológico IB. La estirpe histológica predominante fue el carcinoma epidermoide. La mediana de supervivencia fue superior para los estadios tempranos. La mayor supervivencia a los 5 años correspondió a los estadios IA y IIA. A los 10 años no hubo diferencias en la supervivencia de los pacientes. Conclusiones: La mayor supervivencia a los 5 años de los pacientes sometidos a cirugía de resección pulmonar y linfadenectomía por muestreo correspondió a los que se encontraban en estadios con menor extensión de la enfermedad. Entre los 5 y 10 años después de la cirugía hubo una estabilización en la sobrevida de todos los pacientes, indistintamente del estadio patológico inicial.

Keloids are defined histopathologically as an inflammatory disorder characterized by exhibiting numerous fibroblasts, abnormal vascularization, increased number of proinflammatory immune cells as well as uncontrolled cell proliferation, and exacerbated and disorganized deposition of extracellular matrix (ECM) molecules. Importantly, many of these ECM molecules display N- and O-linked glycan residues and are considered as potential targets for galectin-1 (Gal-1) and galectin-3 (Gal-3). Nevertheless, the presence and localization of Gal-1 and Gal-3 as well as the interactions with some of their binding partners in keloid tissues have not been considered. Here, we show that in the dermal thickening of keloids, versican, syndecan-1, fibronectin, thrombospondin-1, tenascin C, CD44, integrin β1, and N-cadherin were immunolocalized in the elongated fibroblasts that were close to the immune cell infiltrate, attached to collagen bundles, and around the microvasculature and in some immune cells. We also show that Gal-1 and Gal-3 were present in the cytoplasm and along the cell membrane of some fibroblasts and immune and endothelial cells of the dermal thickening. We suggest that Gal-1 and Gal-3, in concert with some of the ECM molecules produced by fibroblasts and by immune cells, counteract the inflammatory response in keloids. We also proposed that Gal-1 and Gal-3 through their binding partners may form a supramolecular structure at the cell surface of fibroblasts, immune cells, endothelial cells, and in the extracellular space that might influence the fibroblast morphology, adhesion, proliferation, migration, and survival as well as the inflammatory responses.

Introduction. Childhood depression is a disease that is becoming more frequent. Few reports address parental perception of children depressive symptoms, and these studies have not been carried out in community samples. Objective. To evaluate the correlation and agreement of depressive symptoms in school-age children, and their parent’s perception about emotional and conduct abnormalities. Method. A transversal study was performed in 284 children who filled a Children Depression Inventory. One of their parents filled a Strengths and Difficulty Questionnaire, and correlation between scores and subcomponent scores were assessed. Agreement between presence of depressive symptoms in children and their parent’s perception of abnormal emotional and/or conduct reports was also obtained. Results. 47 children were identified with depressive symptoms. We found moderate correlation between scores. We did not find agreement between the presence of depressive symptoms in the children and the report of emotional and conduct abnormalities by parents. Discussion and conclusion. There is a modest correlation between depressive symptom severity and parental perception of abnormal emotions and/or behaviors. We found no evidence of agreement between these domains in our study, which suggests that parents fail to perceive negative emotions or conducts as depressive symptoms in their children. Parental reports should be addressed by healthcare workers, and their emotional significance should be interpreted. An intentional search of depressive symptomatology in children should be a priority.

Von Willebrand Factor (vWF) is constitutively secreted by the endothelium and incorporated in the fibrin clots under slow clotting conditions. The aim of the present work was to study the effect of vWF on clot structure and lysis. Purified fibrinogen was mixed with vWF or Tris-buffered saline and clotted with thrombin - activated factor XIII. Fibrin polymerization was followed by turbidity at 350 nm during 2.5 h. After this time, plasmin was added on the top of the clots, and the optical density (OD) was read until baseline values. vWF effect on network[Combining Acute Accent]s porosity was evaluated by permeation using the same clotting conditions as for fibrin polymerization. Clot structure was visualized and analyzed by laser scanning confocal microscopy (LSCM). The rate of fibrin polymerization was 1.47 mOD/s in the presence of vWF and 0.5 mOD/s when vWF was not added (P < 0.05). The fibrin lysis rate was approximately four times faster when vWF was added to fibrinogen. The fibrin network porosity was (20.4 ± 1.6) × 10 cm with vWF and (8.3 ± 1.2) × 10 cm without external vWF (P < 0.05). The analysis of LSCM images showed that vWF increased fibrin fibers diameter and the networks[Combining Acute Accent] pores size. In conclusion, vWF covalently crosslinked to fibrin modify its structure (increases fibrin diameter and the pores filling space of the meshwork) that accelerates the fibrin lysis rate.

This paper examines the relationship between national investment and saving in Colombia during the period 1925-2011 -- Consistent with Cardenas and Escobar (1998), an Error Correction Model is used to examine short and long run effects -- The results provide evidence that investment and saving are co-integrated during the study period -- The results for the co-integration vector, with and without structural breaks, indicate that capital mobility was low, which is consistent with the Feldstein – Horioka [1980] paradox -- The results imply that increases in domestic saving rates reduce the mobility of financial capital in Colombia, Este artículo examina la relación entre la inversión nacional y el ahorro en Colombia durante el periodo 1925-2011 -- De manera consistente con Cárdenas y Escobar (1998), se utiliza un Modelo de Corrección de Errores para examinar los efectos de corto y largo plazo -- Los resultados evidencian que la inversión y el ahorro están co-integradas durante el periodo de estudio -- Los resultados para el vector de cointegración, incluyendo quiebres estructurales y sin incluirlos, indican que la movilidad del capital era baja, lo cual es consistente con la paradoja de Feldstein y Horioka (1980) -- Los resultados implican que aumentos en las tasas domésticas de ahorro reducen la movilidad del capital financiero en Colombia

Background Abnormal fibrinogens can be caused by clinically silent hereditary mutations. A new case was detected accidentally in an 11-year-old girl when routine pre-operative coagulation tests were performed for nasal turbinate surgery. Methods The fibrinogen genes FGA, FGG and FGB were sequenced using standard protocols. The kinetics of fibrin formation were followed by turbidity at 350 nm. Purified fibrinogen was incubated with plasmin, and the degradation products analyzed by SDS/PAGE. The formation of fibrinogen-albumin complexes was analyzed by immunobloting. Fibrin structure was examined in a Nikon Eclipse TE 2000-U laser microscope. Secretion of the variant protein was analyzed directly by reverse phase-electrospray time of flight-mass spectrometry (TOF-MS). Results DNA sequencing revealed a novel heterozygous g. 3057 C > T mutation in the FGA that predicts a p. Arg104 > Cys substitution, in the proband and her father. Both patients were asymptomatic with low functional and antigen fibrinogen concentrations. The proband’s plasma fibrinogen polymerization was almost normal, with a 12% decrease in the final turbidity, while, the father’s fibrin formation had a diminished slope and final turbidity (2.5× and 40%, respectively). Aα Arg104 is located at a plasmin cleavage site in the coiled-coil region of fibrinogen. However, the father’s fibrinogen plasmin degradation was normal. Although the exchanged Cys introduces an unpaired –SH, immunoblotting showed no fibrinogen-albumin complexes. Furthermore, the plasma clot structure observed by confocal microscopy appeared almost normal. TOF-MS showed that the variant Aα chain was underrepresented in plasma and made up only about 25% of the total. Conclusions The low expression of the Aα Arg104 > Cys chain in circulation could account for the observed hypodysfibrinogenemia. Electronic supplementary material The online version of this article (10.1186/s12878-017-0086-8) contains supplementary material, which is available to authorized users.

The mixing of UHMWPE wastes with other polymers aims to reduce the environmental impact of waste materials. The dynamic rheological behavior of the blends, tensile and abrasion properties, Shore D hardness and impact resistance, and morphology are important in characterizing polymer blends. In this work, we have sought to obtain blends containing different proportions of UHMWPE wastes and LDPE with properties suitable for the manufacture of useful products. The blends exhibit an increase in complex viscosities, storage modulus, and Young's modulus with increasing content of UHMWPE wastes and a decrease in both the maximal elongation and Charpy impact resistance. Summarizing, the addition of up to 60 wt % of industrial fragments of UHMWPE is possible using conventional methods of processing to prepare blends with values of tensile strength, abrasion, and Shore D hardness similar to those of LDPE. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44996.

Biodiversity is not uniformly distributed on earth, with sites more relevant than others, due to their intrinsic properties or their evolutionary and/or biogeographical context. The tropical Andes are globally acknowledged for their importance for preserving high biodiversity and endemism, and at the same time by the high level of anthropogenic pressure. In this study, we assessed the subtribe Pronophilina butterfly diversity, the dominant group in species richness and abundance in the higher Andes, in the influence area of the Paramo de Belmira, Antioquia, Colombia, in the northern part of the Central Cordillera. The contribution of this area to the overall regional Andean butterfly diversity reported for the northern tropical Andes was assessed. In Belmira, 50 Pronophilina species were found, representing approximately one fourth of the known Colombian species of this subtribe and 10% of the overall richness, including unique and geographically restricted species. These results provide evidence on the importance of isolated mountain formations in the northern end of the Andes and confirm the assumption that the Paramo de Belmira is a key conservation component for the high Andean butterfly diversity at the regional level, deserving stronger conservation actions and protection status.

The increase in the intracellular Ca(2+) concentration ([Ca(2+)]i) is the key variable for many different processes, ranging from regulation of cell proliferation to apoptosis. In this work we demonstrated that the sphingolipid sphingosine (Sph) increases the [Ca(2+)]i by inhibiting the sarco(endo)plasmic reticulum Ca(2+)-ATPase (SERCA), in a similar manner to thapsigargin (Tg), a specific inhibitor of this Ca(2+) pump. The results showed that addition of sphingosine produced a release of Ca(2+) from the endoplasmic reticulum followed by a Ca(2+) entrance from the outside mileu. The results presented in this work support that this sphingolipid could control the activity of the SERCA, and hence sphingosine may participate in the regulation of [Ca(2+)]I in mammalian cells.

There is evidence that clot structure can be modulated by endothelial cells, wherein the fibrinogen αC domain plays a major role in the fibrin-cell interaction. The spatial distribution of fibrin fibers from fibrinogen Caracas V and Caracas I, with heterozygous mutation in the αC domain (Aα Ser432Cys and Aα Ser466stop, respectively) on human dermal microvasculature endothelial cells (HMEC-1), was studied by laser scanning confocal microscopy. In order to assess fibrin-cell interaction and the role of the αC domain, preliminary experiments were done with inert microspheres and RGD peptide included in the clotting reaction, and forming clots with fibrinogen fragment X (fibrinogen without αC domain). Groups of stressed fibers were observed near the cell surface and were related to fibrin-cell interactions, which were abolished by the RGD peptide, and by the absence of the αC domain. The fibrin network of fibrinogen Caracas V and Caracas I was very different from that of normal fibrinogen. In general, patient's clots were characterized by very thin, tightly packed fibrin fibers, with a substantially reduced network porosity. Near the cell's surface, both abnormal fibrinogens formed a very fine meshwork, with stressed fibers 'anchored' to the cell surface, a pattern that was lost far from the cell surface. The structure of normal and patient clots performed in the absence of cells resembled that observed far from the cell surface, concluding that Caracas V and Caracas I fibrin was modulated by the presence of endothelial cells.

In this work the kinematics of a three-legged parallel manipulator with asymmetrical limbs and decoupled motions over its moving platform is investigated by means of the theory of screws. The solution of the forward displacement analysis (FDA) is presented in echelon-form solution using a novel procedure based on simple geometric constraints, thus all the feasible locations of the moving platform, with respect to the fixed platform, are computed given a set of generalized coordinates. After, the velocity and acceleration analyses are carried out using the theory of screws. Finally, a numerical example is included and the results obtained via the screw theory are verified with the aid of special commercially available software like MSC.Adams©.

In this work, the kinematic analysis of a five-degrees-of-freedom decoupled parallel manipulator is approached by means of the theory of screws. The architecture of the parallel manipulator under study is such that the translational motion of the moving platform, with respect to the fixed platform, is controlled by means of a central limb provided with two active prismatic joints while its rotational motion is controlled by means of a three-degrees-of-freedom spherical parallel manipulator. The forward position analysis is presented in semiclosed form solution applying recursively the Sylvester dialytic elimination method. On the other hand, the velocity and acceleration analyses are carried out using the theory of screws. Simple and compact expressions to compute the velocity state and the reduced acceleration state of the moving platform, with respect to the fixed platform, are easily derived in this contribution by taking advantage of the Klein form of the Lie algebra se(3). Finally, only few and slight modifications to the proposed method of kinematic analyses are required in order to approach the position, velocity, and acceleration analyses of parallel manipulators with similar topologies.