Repositorio Digital Universidad Simón Bolívar
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Large cells cancer volumetry in chest computed tomography pulmonary images
No full textLung cancer is the leading oncological cause of death in the world. As for
carcinomas, they represent between 90% and 95% of lung cancers; among them, non-small cell
lung cancer is the most common type and the large cell carcinoma, the pathology on which this
research focuses, is usually detected with the computed tomography images of the thorax.
These images have three big problems: noise, artifacts and low contrast. The volume of the
large cell carcinoma is obtained from the segmentations of the cancerous tumor generated, in a
semi-automatic way, by a computational strategy based on a combination of algorithms that, in
order to address the aforementioned problems, considers median and gradient magnitude filters
and an unsupervised grouping technique for generating the large cell carcinoma morphology.
The results of high correlation between the semi-automatic segmentations and the manual ones,
drawn up by a pulmonologist, allow us to infer the excellent performance of the proposed
technique. This technique can be useful in the detection and monitoring of large cell carcinoma
and if it is considering this kind of computational strategy, medical specialists can establish the
clinic or surgical actions oriented to address this pulmonary pathology
Conflicts in the border, the rights and policies of a social pact
No full textLos conflictos de las fronteras entre naciones y los pactos sociales establecen interacciones
entre agentes sociales, derechos y el Estado democrático. El objetivo del artículo es
analizar desde el enfoque sociológico, la relación entre la percepción de existencia de pactos
sociales y los múltiples conflictos. Investigamos la frontera Norte de Santander (Colombia) y
Táchira (Venezuela). El recurso teórico se alía con el punto de vista operativo de la investigación
sobre prácticas sociales, con observación de campo y aplicaciones de encuestas. Entre los hallazgos
destacamos las múltiples interacciones entre Estado y los ciudadanos, pero sin la existencia
de un canal de resolución de cuestiones fundamentales en el espacio territorial y por lo tanto
persisten las inconsistentes posibilidades de un pacto social ante los conflictos en el referido
contexto fronterizo.The conflicts of the borders between nations and the social pacts establish interactions
between social agents, rights and the democratic State. The objective of the article is to analyze, from the sociological point of view, the relationship between the perception of the existence of social pacts and the multiple conflicts. We investigated the northern border of Santander (Colombia) and Táchira (Venezuela). The theoretical resource is combined with the operational point of
view of research on social practices, with field observation and survey applications. Among the
findings we highlight the multiple interactions between the State and the citizens, but without
the existence of a channel for resolving fundamental issues in the territorial space and therefore the inconsistent possibilities of a social pact with respect to conflicts in the aforementioned border context persist
Fatalities by traffic in Maryland and Massachusetts evaluated in the context of a probabilistic random walk between 1994 and 2014
No full textAntecedentes: El análisis de los accidentes de tránsito desde una perspectiva física y matemática puede ayudar a mejorar las estrategias viales de seguridad. Objetivo: Obtener una predicción de la dinámica de fatalidades a causa del tráfico en los estados de Maryland y Massachusetts para los años 2004 y 2014 en el contexto de la caminata al azar probabilista. Métodos: Se realizó un análisis del número de fatalidades totales causadas por el tráfico al año, en los estados de Maryland y Massachusetts entre los años 1994-2003 y 1994-2013. El comportamiento de estos valores fue analizado como una caminata al azar probabilista; para ello se hallaron las longitudes probabilistas para cada año, durante el periodo estudiado y se analizaron cuatro espacios de probabilidad, con los que fue posible analizar su comportamiento, para establecer una predicción del número de fatalidades totales causadas por el tráfico para los años 2004 y 2014. Resultados: Las predicciones para los años 2014 y 2004 para Maryland y Massachusetts al ser comparados con los valores reales el porcentaje de acierto fue del 98%. Conclusión principal: el comportamiento de las fatalidades de tráfico en Maryland y Massachusetts presentó una autoorganización predecible desde el contexto de la caminata al azar probabilista, constituyéndose como una herramienta útil para el análisis del funcionamiento de las estrategias de seguridad vial.Introduction: The analysis of injuries caused by traffic from a physical and mathematical perspective can help improve road safety strategies. Objective: Predict the dynamics of traffic fatalities in the states of Maryland and Massachusetts for the years 2004 and 2014 in the context of probabilistic random walk. Methods: An analysis was made of the number of total fatalities caused by traffic per year, in the states of Maryland and Massachusetts between the years 1994-2003 and 1994-2013. The behavior of these values was analyzed as a probabilistic random walk; for this, the probabilistic lengths were found for each year, during the period studied and four probability spaces were analyzed, with which it was possible to analyze their behavior, to establish a prediction of the number of total fatalities caused by traffic for the years 2004 and 2014. Results: The predictions for the years 2014 and 2004 for Maryland and Massachusetts when compared with the real values, the percentage of success was 98%. Main conclusion: The predictions for the years 2014 and 2004 for Maryland and Massachusetts when compared with the real values, the percentage of success was 98%. Conclusions: the behavior of traffic fatalities in Maryland and Massachusetts presented a predictable self-organization from the context of probabilistic random walk, constituting a useful tool for analyzing the operation of road safety strategies
Psychological affectations on victims of the armed conflict
No full textObjetivos: Analizar las afectaciones psicológicas en víctimas
del conflicto armado en Colombia.
Materiales y métodos: Se aplicó el inventario de síntomas
SCL-90 a 455 personas reconocidas como víctimas. Se analizaron
las puntuaciones directas y puntuaciones T mediante
baremos estandarizados, se aplicaron medidas de tendencia
central y la prueba de “t student” para la identificación de diferencias
significativas por rangos de edad y sexo.
Resultados: Se identificó sintomatología clínica y psiquiátrica
correspondiente a trastornos de estados de ánimo, de
ansiedad (estrés postraumático) y trastornos de angustia.
Se encontraron diferencias significativas entre hombres y
mujeres en los índices de severidad global y el índice de
síntomas positivos.
Conclusiones: Se hace necesario abordar procesos de intervención
de manera inter- y trans- (disciplinar, sectorial e
institucional), integrando la experiencia de afectación psicológica
de las víctimas.Objectives: The main purpose of the study was to analyze
the psychological affectations on victims of the armed conflict
in Colombia.
Materials and methods: The SCL-90 symptom inventory
was applied to 455 people recognized as victims. Direct
scores and T scores were analyzed by standardized scales,
central tendency measures and student t test were applied to
identify significant differences by age and sex ranges.
Results: Clinical and psychiatric symptomatology corresponding
to disorders of mood, anxiety (post-traumatic
stress) and distress disorders were identified. Significant differences
were found between men and women in the indexes
of global severity and the index of positive symptoms.
Conclusions: It is necessary to approach inter- and transintervention
processes (disciplinary, sectoral and institutional),
integrating the experience of psychological affectation of
the victims
Nuclear factor erythroid 2 – related factor 2 and its relationship with cellular response in nickel exposure: a systems biology analysis
No full textBackground: Nickel and nickel-containing compounds (NCC) are known human carcinogens. However, the precise
molecular mechanisms of nickel-induced malignant transformation remain unknown. Proposed mechanisms
suggest that nickel and NCC may participate in the dual activation/inactivation of enzymatic pathways involved in
cell defenses against oxidative damage, where Nuclear factor-erythroid 2 related factor 2 (Nrf2) plays a central role.
Methods: For assessing the potential role of proteins involved in the Nrf2-mediated response to nickel and NCC
exposure, we designed an interactome network using the STITCH search engine version 5.0 and the STRING
software 10.0. The major NCC-protein interactome (NCPI) generated was analyzed using the MCODE plugin, version
1.5.1 for the detection of interaction modules or subnetworks. Main centralities of the NCPI were determined with
the CentiScape 2.2 plugin of Cytoscape 3.4.0 and main biological processes associated with each cluster were
assessed using the BiNGO plugin of Cytoscape 3.4.0.
Results: Water-soluble NiSO4 and insoluble Ni3S2 were the most connected to proteins involved in the NCPI
network. Nfr2 was detected as one of the most relevant proteins in the network, participating in several
multifunctional protein complexes in clusters 1, 2, 3 and 5. Ontological analysis of cluster 3 revealed several
processes related to unfolded protein response (UPR) and response to endoplasmic reticulum (ER) stress.
Conclusions: Cellular response to NCC exposure was very comparable, particularly concerning oxidative stress
response, inflammation, cell cycle/proliferation, and apoptosis. In this cellular response, Nfr2 was highly centralized
and participated in several multifunctional protein complexes, including several related to ER-stress. These results
add evidence on the possible Ni2+ induced – ER stress mainly associated with insoluble NCC. In this scenario, we
also show how protein degradation mediated by ubiquitination seems to play key roles in cellular responses to Ni
Mathematical argumentation in the classroom
No full textThe article shares some elements of comprehensive type about "mathematical
argumentation in the classroom"; whose analysis, was made from two fundamental categories
in the development of an oral mathematical argumentation process for the conviction,
contradiction and validation of a written mathematical argumentation process. The research
addressed two central categories of argumentation as a discursive form, the first one is the
epistemic position, and the second one is the discursive position that students unveil at the time
of mathematically arguing the solution to a problem situation. The research was developed
under the interpretative paradigm through the design of a case study directed by the theory and
technique of a focal group, for the collection of information. In the findings, difficulties in the
passage were evidenced from the semantic to the theoretical from the epistemic position;
regarding the discursive position, the presence of three discursive forms was revealed:
description, explanation and argumentation, the latter being the least used by the students
Problem solving strategy in the teaching and learning processes of quantitative reasoning
No full textThe study presents an analysis of Polya's problem-solving strategy used in the training
processes of quantitative reasoning competence in students of the Universidad Simón Bolívar,
San José de Cúcuta, Colombia. The research was based on a descriptive design and had an
intentional sample of 58 students who were studying the sciences and general competencies
elective. For the collection of information, a diagnostic test (pre-test) and a final test (post-test)
were applied, in order to check the incidence of the applied strategy. The results showed a
significant improvement in the final results obtained by the students in each of the processes
formed: interpretation, representation and modeling, and argumentation
ADGRL3 (LPHN3) variants predict substance use disorder
No full textGenetic factors are strongly implicated in the susceptibility to develop externalizing syndromes such as attentiondeficit/
hyperactivity disorder (ADHD), oppositional defiant disorder, conduct disorder, and substance use disorder
(SUD). Variants in the ADGRL3 (LPHN3) gene predispose to ADHD and predict ADHD severity, disruptive behaviors
comorbidity, long-term outcome, and response to treatment. In this study, we investigated whether variants within
ADGRL3 are associated with SUD, a disorder that is frequently co-morbid with ADHD. Using family-based, case-control,
and longitudinal samples from disparate regions of the world (n = 2698), recruited either for clinical, genetic
epidemiological or pharmacogenomic studies of ADHD, we assembled recursive-partitioning frameworks
(classification tree analyses) with clinical, demographic, and ADGRL3 genetic information to predict SUD susceptibility.
Our results indicate that SUD can be efficiently and robustly predicted in ADHD participants. The genetic models used
remained highly efficient in predicting SUD in a large sample of individuals with severe SUD from a psychiatric
institution that were not ascertained on the basis of ADHD diagnosis, thus identifying ADGRL3 as a risk gene for SUD.
Recursive-partitioning analyses revealed that rs4860437 was the predominant predictive variant. This new
methodological approach offers novel insights into higher order predictive interactions and offers a unique
opportunity for translational application in the clinical assessment of patients at high risk for SUD
Diphenyl Ditelluride: Redox-Modulating and Antiproliferative Properties
No full textTellurium is a rare element that has been regarded as a toxic, nonessential element, and its biological role is not clearly established.
In addition, the biological effects of elemental tellurium and some of its organic and inorganic derivatives have been studied, leading
to a set of interesting and promising applications. Diphenyl ditelluride (DPDT), an organic tellurium derivate, showed antioxidant,
antigenotoxic, antimutagenic, and anticancer properties. The antioxidant and prooxidant properties of DPDT are complex and
depend on experimental conditions, which may explain the contradictory reports of these properties. In addition, DPDT may
exert its effects through different pathways, including distinct ones to those responsible for chemotherapy resistance phenotypes:
transcription factors, membrane receptors, adhesion, structural molecules, cell cycle regulatory components, and apoptosis
pathways. This review aims to present recent advances in our understanding of the biological effects, therapeutic potential, and
safety of DPDT treatment. Moreover, original results demonstrating the cytotoxic effects of DPDT in different mammalian cell
lines and systems biology analysis are included, and emerging approaches for possible future applications are inferred
Engineering a single-chain antibody against Trypanosoma cruzi metacyclic trypomastigotes to block cell invasion
No full textTrypanosoma cruzi is a flagellate protozoan pathogen that causes Chagas disease. Currently
there is no preventive treatment and the efficiency of the two drugs available is limited
to the acute phase. Therefore, there is an unmet need for innovative tools to block transmission
in endemic areas. In this study, we engineered a novel recombinant molecule able to
adhere to the T. cruzi surface, termed scFv-10D8, that consists of a single-chain variable
fragment (scFv) derived from mAb-10D8 that targets gp35/50. The synthetic gene encoding
scFv-10D8 was cloned and fused to a 6×His tag and expressed in a prokaryotic expression
system. Total periplasmic or 6xHis tag affinity-purified fractions of scFv-10D8 retained the
capacity to bind to gp35/50, as shown by Western blot analyses. Pre-incubation of metacyclic
trypomastigotes with scFv-10D8 showed a remarkable reduction in cell invasion capacity.
Our results suggest that scFv-10D8 can be used in a paratransgenic approach to target parasites
in insect vectors, avoiding dissemination of infective forms. Such advances in the
development of this functional molecule will surely prompt the improvement of alternative
strategies to control Chagas disease by targeting mammalian host stages