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Imagen de apoyo de  Somatic mosaicism in a Cornelia de Lange patient with NIPBL mutation identified by different Next Generation Sequencing approaches

Somatic mosaicism in a Cornelia de Lange patient with NIPBL mutation identified by different Next Generation Sequencing approaches

Por: Carolina; Gil-Rodríguez Baquero Montoya | Fecha: 2014

Abstract: Cornelia de Lange Syndrome (CdLS) is an autosomal dominant (NIPBL, SMC3 and RAD21) or X-linked (SMC1A and HDAC8) disorder, characterized by distinctive craniofacial appearance, growth retardation, intellectual disability and limb anomalies. Its clinical presentation can be extremely variable. Here we report on a girl with classical CdLS phenotype, growth retardation, intellectual disability and gastroesophageal reflux disease, who is mosaic for the c.6647A>C mutation in the NIPBL gene. While this mutation was undetected by standard Sanger sequencing, it was identified by subsequent exome and panel sequencing approaches. Allele quantification by pyrosequencing showed the presence of the mutation in about 10%, 23.5% and 46.5% of DNA samples from peripheral blood leukocytes, buccal epithelial cells and fibroblasts, respectively. NIPBL mutations in a mosaic state are a frequent cause of CdLS, but clinical diagnosis of these patients can be challenging. In our case, the panel enriched sequencing as well as the exome sequencing clearly demonstrated to be very sensitive tools for mosaic mutation detection.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos
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Somatic mosaicism in a Cornelia de Lange patient with NIPBL mutation identified by different Next Generation Sequencing approaches

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Imagen de apoyo de  Transcranial Direct Current Stimulation to the Left Dorsolateral Prefrontal Cortex Improves Cognitive Control in Patients With Attention-Deficit/Hyperactivity Disorder: A Randomized Behavioral and Neurophysiological Study

Transcranial Direct Current Stimulation to the Left Dorsolateral Prefrontal Cortex Improves Cognitive Control in Patients With Attention-Deficit/Hyperactivity Disorder: A Randomized Behavioral and Neurophysiological Study

Por: Laura; Gómez-Bernal Dubreuil-Vall | Fecha: 2021

Abstract: BACKGROUND: Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder associated with significant morbidity and mortality that may affect over 5% of children and approximately 2.8% of adults worldwide. Pharmacological and behavioral therapies for ADHD exist, but critical symptoms such as dysexecutive deficits remain unaffected. In a randomized, sham-controlled, double-blind, crossover mechanistic study, we assessed the cognitive and physiological effects of transcranial direct current stimulation (tDCS) in 40 adult patients with ADHD in order to identify diagnostic (cross-sectional) and treatment biomarkers (targets). METHODS: Patients performed three experimental sessions in which they received 30 minutes of 2 mA anodal tDCS targeting the left dorsolateral prefrontal cortex, 30 minutes of 2 mA anodal tDCS targeting the right dorsolateral prefrontal cortex, and 30 minutes of sham. Before and after each session, half the patients completed the Eriksen flanker task and the other half completed the stop signal task while we assessed behavior (reaction time, accuracy) and neurophysiology (event-related potentials). RESULTS: Anodal tDCS to the left dorsolateral prefrontal cortex modulated cognitive (reaction time) and physiological (P300 amplitude) measures in the Eriksen flanker task in a state-dependent manner, but no effects were found in the stop signal reaction time of the stop signal task. CONCLUSIONS: These findings show procognitive effects in ADHD associated with the modulation of event-related potential signatures of cognitive control, linking target engagement with cognitive benefit, proving the value of eventrelated potentials as cross-sectional biomarkers of executive performance, and mechanistically supporting the statedependent nature of tDCS. We interpret these results as an improvement in cognitive control but not action cancellation, supporting the existence of different impulsivity constructs with overlapping but distinct anatomical substrates, and highlighting the implications for the development of individualized therapeutics.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos
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Transcranial Direct Current Stimulation to the Left Dorsolateral Prefrontal Cortex Improves Cognitive Control in Patients With Attention-Deficit/Hyperactivity Disorder: A Randomized Behavioral and Neurophysiological Study

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Imagen de apoyo de  FluxCABG: Intraoperative Flowmetry in Myocardial Revascularization Surgery as a Prognostic Factor for Major Cardiac Events FluxCABG: Intraoperative Flowmetry in Myocardial Revascularization Surgery as a
Prognostic Factor for Major Cardiac Events

FluxCABG: Intraoperative Flowmetry in Myocardial Revascularization Surgery as a Prognostic Factor for Major Cardiac Events FluxCABG: Intraoperative Flowmetry in Myocardial Revascularization Surgery as a Prognostic Factor for Major Cardiac Events

Por: John Karol; Nafeh-Abi-Rezk Ramírez | Fecha: 2021

Abstract: Introduction: The occlusion of coronary grafts used during myocardial revascularization surgery is a relatively frequent event. It has been described that between 7–15% are affected before 24 hours, and up to 30% per year being mainly related to technical errors. Pulsed Doppler offers the necessary requirements for an adequate intraoperative evaluation of grafts. The main objective of this study is to demonstrate it using the Fluxvisum prototype. Material and method: Longitudinal study carried out between March 2012 and June 2016 in surgically revascularized patients in which the elaborated coronary grafts were evaluated intraoperatively using pulsed Doppler. Results: 110 patients were studied, predominantly men older than 60 years, with a high prevalence of HT, DM and previous AMI, and diagnosis on admission to NSTEMI. The average measurements were: Qmed:31.7ml/min, PI:3.2, DFI:70.2. The Qmed was the flowmeter variable that was most statistically associated with the appearance of major cardiac events. In the logistic regression, the quality of LAD revascularization stood out as the main predictor of MACE (p=0.050, OR:2.599, 95%CI:0.972-6.947), death (p=0.004, OR:13.947, 95%CI:2,311-84,163), AMI (p=0.000, OR:11.331, 95%CI:2.995-42.867) and perioperative acute ischemia (p=0.049, OR:2.864, 95%CI:0.997-8.222). Conclusions: Pulsed Doppler flowmetry proved to be a tool with high prognostic power as a predictor of postoperative comorbidity and major cardiac events in surgically revascularized patients. Resumen: Introducción: La oclusión de los injertos coronarios utilizados durante la cirugía de revascularización miocárdica es un hecho relativamente frecuente. Se ha descrito que entre el 7–15% se afectan antes de las 24 horas, y hasta un 30% al año relacionándose principalmente con errores técnicos. El Doppler pulsado ofrece los requerimientos necesarios para una adecuada evaluación intraoperatoria de los injertos. El objetivo principal de este estudio es demostrarlo utilizando el prototipo Fluxvisum. Material y método: Estudio longitudinal realizado entre marzo de 2012 y junio del 2016 en pacientes revascularizados quirúrgicamente en los que los injertos coronarios elaborados fueron evaluados intraoperatoriamente utilizando Doppler pulsado. Resultados: Se estudiaron 110 enfermos predominantemente hombres mayores de 60 años, con una alta prevalencia de hipertensión arterial (HTA), diabetes mellitus (DM) e infarto agudo de miocardio (IMA) previo, y diagnostico al ingreso de SCASEST. Las mediciones promedio fueron: Qmed:31,7ml/min, IP:3,2, DFI:70,2. El Qmed fue la variable flujométrica que más se asoció estadísticamente con la aparición de eventos cardiacos mayores. En la regresión logística, la calidad de la revascularización de la DA destacó como el principal factor predictor de MACE (p=0,050, OR:2,599, CI95%:0,972–6,947), muerte (p=0,004, OR:13,947, CI95%:2,311–84,163), IMA (p=0,000, OR:11,331, CI95%:2,995–42,867) e isquemia aguda perioperatoria (p=0,049, OR:2,864, CI95%:0,997–8,222). Conclusiones: La flujometría con Doppler pulsado demostró ser una herramienta que tiene un alto poder pronóstico como predictor de comorbilidad posoperatoria y eventos cardiacos mayores en pacientes revascularizados quirúrgicamente.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos
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FluxCABG: Intraoperative Flowmetry in Myocardial Revascularization Surgery as a Prognostic Factor for Major Cardiac Events FluxCABG: Intraoperative Flowmetry in Myocardial Revascularization Surgery as a Prognostic Factor for Major Cardiac Events

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Imagen de apoyo de  Polyphenol intake and epithelial ovarian cancer risk in the European prospective Investigation into Cancer and Nutrition (EPIC) study

Polyphenol intake and epithelial ovarian cancer risk in the European prospective Investigation into Cancer and Nutrition (EPIC) study

Por: Catalina; Cayssials Londoño Cañola | Fecha: 2021

Abstract: Despite some epidemiological evidence on the protective effects of polyphenol intake on epithelial ovarian cancer (EOC) risk from case-control studies, the evidence is scarce from prospective studies and non-existent for several polyphenol classes. Therefore, we aimed to investigate the associations between the intake of total, classes and subclasses of polyphenols and EOC risk in a large prospective study. The study was conducted in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort, which included 309,129 adult women recruited mostly from the general population. Polyphenol intake was assessed through validated country-specific dietary questionnaires and the Phenol-Explorer database. During a mean follow-up of 14 years, 1469 first incident EOC cases (including 806 serous, 129 endometrioid, 102 mucinous, and 67 clear cell tumours) were identified. In multivariable-adjusted Cox regression models, the hazard ratio in the highest quartile of total polyphenol intake compared with the lowest quartile (HRQ4vsQ1) was 1.14 (95% CI 0.94–1.39; p-trend = 0.11). Similarly, the intake of most classes and subclasses of polyphenols were not related to either overall EOC risk or any EOC subtype. A borderline statistically significant positive association was observed between phenolic acid intake (HRQ4vsQ1 = 1.20, 95% CI 1.01–1.43; p-trend = 0.02) and EOC risk, especially for the serous subtype and in women with obesity, although these associations did not exceed the Bonferroni correction threshold. The current results do not support any association between polyphenol intake and EOC in our large European prospective study. Results regarding phenolic acid intake need further investigation.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos
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Polyphenol intake and epithelial ovarian cancer risk in the European prospective Investigation into Cancer and Nutrition (EPIC) study

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Imagen de apoyo de  Inter-individual variability of Lifetime Stress exposure on the oncological characteristics of  TNBC patients: Do coping styles moderate the relationship? Role of SNS, HPA axis, and Cortical structures

Inter-individual variability of Lifetime Stress exposure on the oncological characteristics of TNBC patients: Do coping styles moderate the relationship? Role of SNS, HPA axis, and Cortical structures

Por: Ingrid Lizeth Lizarazo Rodríguez | Fecha: 2021

Abstract: Biological and physiological changes in response to stress are crucial to achieving adaption to environmental constraints. Typical stress responses activate the sympathetic nervous system and the hypothalamic-pituitary-adrenal cortical axis, which aim to maintain homeostasis in response to demands and influence various biological responses at neuroendocrine, cellular, and immune levels. In particular, there is compelling evidence showing the devastating effects of high-stress levels on immune responses and brain functionality. In that sense, data suggest that a sustained stress-physiological response predicts decreases in immunity and leads to allostatic load, the wear, and tear of biological systems. Similarly, in cancer research, chronic stress levels have been reported to impair the bodysurveillance systems and be related to cancer incidence, progression, and mortality. Despite the evidence demonstrating the associations between stress and cancer, there are limited data on whether lifetime stress exposure relates to clinical indicators of cancer aggressiveness. Considering the evidence showing the adverse effects of prolonged stress exposure on cancer disease, this thesis aimed to explore the relationship between lifetime stress exposure and the clinical characteristics of tumor-aggressiveness in a cohort of patients affected with triple-negative breast cancer (TNBC). Likewise, as research has shown that coping responses moderate the stress-physiological response, we aimed to investigate the role of coping responses in moderating the association between tumor aggressiveness and lifetime stress exposure. According to the scientific literature, high-stress levels would increase physiological arousal and allostatic load favoring a debilitated immune system. Thus, we hypothesized finding positive associations between lifetime stress exposure and tumor-aggressiveness. In the same line, we suspected that adaptative coping styles would be negatively related to tumoraggressiveness. The participants of this study were 29 women diagnosed with TNBC who were treated in the University Hospital for Gynecology Pius-Hospital (Oldenburg, Germany). Correlation and moderation regression analyses with the use of composite scores were conducted. Overall, we could not demonstrate significant associations between lifetime stress exposure and coping responses on the clinical indicators of tumor aggressiveness in this cohort of patients. Possible explanations for these results are discussed, and suggestions for future research are provided. This study was the first to investigate the effect of lifetime stress exposure and coping response on the aggressive tumor characteristics of TNBC. We provided a deep theoretical framework to understand the interplay between biological and psychological aspects of cancer disease, and we hope that our recommendations may serve as a base for upcoming studies.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Tesis
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Inter-individual variability of Lifetime Stress exposure on the oncological characteristics of TNBC patients: Do coping styles moderate the relationship? Role of SNS, HPA axis, and Cortical structures

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Imagen de apoyo de  The effect of environmental variable selection in the prediction of Seasonal Influenza cases using machine learning

The effect of environmental variable selection in the prediction of Seasonal Influenza cases using machine learning

Por: Stefany Brigetty Guarnizo Peralta | Fecha: 2021

Abstract: Background: Seasonal Influenza is considered to be a cyclic and ordered sequence of values, influenced by external factors that can be predicted and used to detect disease outbreaks and monitoring. In machine learning, the key challenges that limit these analyses are in model explainability and limitations associated with ecological bias. Aim: Determine the best environmental variable selection method to predict Seasonal Influenza in Norway, using an environmental medicine approach combined with machine learning techniques. Methods: This is a quasi-experimental study that compares three approaches (non-variable selection, isolate component, and multipollutant mixture), represented in five methods (univariable, bivariable, multivariable AME, multivariable PCA, multivariable LDA). Per method, the best co-variable combination will be performed, following the internal rules of each method. The best covariable combination is the result of three components: variable selection, validation data set and lag. The first one involves 13 environmental variables (temperature, relative humidity, specific humidity, air pressure, wind speed, precipitation, CO, NO, NO2, O3, PM10, PM2,5 and SO2); second one compares a test dataset compiled from the data from 2019, last year (2018) and a synthetic environmental (avg. 2013-2018) data set in the validation process; and the third one compares a combination of lag from 0 to 12. All the predictions are made using ARIMA algorithm. The evaluation is given in terms of MAE, MSE, RMSE, OR. The training set is from 2 Jun 2013 (week 22/2013) to 28 May 2018 (week 21/2018), and test set is from (week 22/2018) to (week 21/2019) with a window of predictions of 52 weeks. Results: The increment of dimensionality in the environmental variable selection introduce different noise levels and optimize the prediction. Considerations that impact the explainability, usability, ecological bias and performance will be described. Conclusion: The increment of dimensionality in the variable selection has a better impact on performance than using complex algorithms.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Tesis
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The effect of environmental variable selection in the prediction of Seasonal Influenza cases using machine learning

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Imagen de apoyo de  Analysis of the Prevalence and Incidence of Cleft Lip and Palate in Colombia

Analysis of the Prevalence and Incidence of Cleft Lip and Palate in Colombia

Por: Herney Alonso; Guarnizo Peralta Rengifo Reina | Fecha: 2020

Abstract: Objective: To analyze the population prevalence and birth prevalence of oral clefts in Colombia from 2009 to 2017. Methods: A cross-sectional study using information from the National Administrative Records of Colombia. The data came from 2 types of administrative records (Surveillance System and the Individual Registry of Service Provision) and the oral health national survey. Population prevalence and birth prevalence by type of cleft lip and/or cleft (CL/P) ratios were calculated using Poisson distribution for count data and to assess stationary tests on time series (Dickey-Fuller) and (Phillips-Perron) was used. Results: Population prevalence in Colombia was 3.27 per 10 000 inhabitants (95% confidence interval [CI], 3.21-3.32) and birth prevalence was 6.0 per 10 000 live births (95% CI, 5.67-6.35). Bogot´a have the highest population prevalence with CL/P. In the analysis of trends for the prevalence proportion by type of clefts in newborn babies with cleft, it was observed that the highest proportion was for babies with CLP. Cleft lip (CL) has increased from 17.4% in 2014 to 34.2% in 2017, cleft palate (CP) has decreased from 32.9% to 20.2%; and CLP changed from 49.6% to 45.5% in the same period. Conclusions: The population prevalence was 3.27 per 10 000 inhabitants. Births prevalence was 6.0 per 10 000 live births, and Orinoquia and Amazonia have higher rates than the national average. The administrative registers are adequate systems to know the behavior of oral clefts. The CL/P had a nonstationary trend during the period 2014 to 2017.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos
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Analysis of the Prevalence and Incidence of Cleft Lip and Palate in Colombia

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Imagen de apoyo de  Population prevalence and trends of oral clefts in Colombia: analysis by departments

Population prevalence and trends of oral clefts in Colombia: analysis by departments

Por: Herney Alonso; Guarnizo Peralta Rengifo Reina | Fecha: 2021

Abstract: Objective: Determine the population prevalence and trends of cleft lip and / or palate (CL/P) by department for Colombia in the period 2009 - 2015. Methods: Prevalence study based on Individual Registry of Health Services in general population from 2009 to 2015. All people diagnosed with CL/P were included for all ages, type of diagnosis and any type of health services in the mentioned period. The prevalence rate was calculated by period and point for each year, for each department and according to the type of cleft. Stationarity on time series was evaluated using (Dickey-Fuller) and (Phillips-Perron), the trends and prevalence ratios were calculated using Poisson regression. Results: 15,225 people with CL/P were identified, where 53.3% were men. The national period prevalence of CL/P is 3.37 per 10 000 (IC95%: 3.3-3.4) with upward trend (PR = 1.34 95% CI: 1.0 - 1.8 p = 0.05) and non-stationary behavior. The national period prevalence of CL is 0.93 per 10 000, CP 1.17 per 10 000 and CLP 1.26 per 10 000, where CLP is sub classify into CLPu (0.83 per 10 000), and CLPb (0.43 per 10 000). At the departmental level, the highest CL/P prevalence is Guaviare (11.2 95% CI: 8.6 – 14.2), followed by Guainía (8.4 95% CI:5.4 – 12.2) and the lowest Quindío (0.49 95% CI: 0.3 – 0.7) Conclusions: In Colombia, the national period prevalence of CL/P is 3.37 per 10 000 with upward trend at national level indicates an increase on prevalence from 2009 to 2015.
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Population prevalence and trends of oral clefts in Colombia: analysis by departments

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Imagen de apoyo de  Impact of dimensionality on nowcasting seasonal influenza with environmental factors

Impact of dimensionality on nowcasting seasonal influenza with environmental factors

Por: Stefany Brigetty; Miliou Guarnizo Peralta | Fecha: Ca. 2020

Abstract: Seasonal influenza is an infectious disease of multi-causal etiology and a major cause of mortality worldwide that has been associated with environmental factors. In the attempt to model and predict future outbreaks of seasonal influenza with multiple environmental factors, we face the challenge of increased dimensionality that makes the models more complex and unstable. In this paper, we propose a nowcasting and forecasting framework that compares the theoretical approaches of Single Environmental Factor and Multiple Environmental Factors. We introduce seven solutions to minimize the weaknesses associated with the increased dimensionality when predicting seasonal influenza activity levels using multiple environmental factors as external proxies. Our work provides evidence that using dimensionality reduction techniques as a strategy to combine multiple datasets improves seasonal influenza forecasting without the penalization of increased dimensionality.
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Impact of dimensionality on nowcasting seasonal influenza with environmental factors

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Imagen de apoyo de  Severe ipsilateral musculoskeletal involvement in a Cornelia de Lange patient with a novel NIPBL mutation

Severe ipsilateral musculoskeletal involvement in a Cornelia de Lange patient with a novel NIPBL mutation

Por: Carolina; Gil-Rodríguez Baquero Montoya | Fecha: 2014

Abstract: Cornelia de Lange Syndrome (CdLS) is a congenital autosomal dominant (NIPBL, SMC3 and RAD21) or Xlinked (SMC1A and HDAC8) disorder characterized by facial dysmorphism, pre and postnatal growth retardation, developmental delay and/or intellectual disability, and multiorgan involvement. Musculoskeletal malformations are usually bilateral and affect mainly the upper limbs; the range goes from brachyclinodactyly to severe reduction defects. Instead lower extremities are usually less and mildly involved. Here, we report on a 3-year-old Senegalese boy with typical craniofacial CdLS features, pre and postnatal growth retardation, atrial septal defect, developmental delay and right ipsilateral limb malformations, consistent with oligodactyly of the 3rd and 4th fingers, tibial agenesis and fibula hypoplasia. Exome sequencing and Sanger sequencing showed a novel missense mutation in NIPBL gene (c.6647A>G; p.(Tyr2216Cys)), which affects a conserved residue located within NIPBL HEAT repeat elements. Pyrosequencing analysis of NIPBL gene, disclosed similar levels of wild-type and mutated alleles in DNA and RNA samples from all tissues analyzed (oral mucosa epithelial cells, peripheral blood leukocytes and fibroblasts). These findings indicated the absence of somatic mosaicism, despite of the segmental asymmetry of the limbs, and confirmed biallelic expression for NIPBL transcripts, respectively. Additionally, conditions like Split-hand/foot malformation with long-bone deficiency secondary to duplication of BHLHA9 gene have been ruled out by the array-CGH and MLPA analysis. To our knowledge, this is the first CdLS patient described with major ipsilateral malformations of both the upper and lower extremities, that even though this finding could be due to a random event, expands the spectrum of limb reduction defects in CdLS.
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Severe ipsilateral musculoskeletal involvement in a Cornelia de Lange patient with a novel NIPBL mutation

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