69 research outputs found

    Herramienta de diagnóstico para determinar la cultura organizacional de una Pyme colombo-venezolana. Caso BCR Supply Colombia, S.A.S

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    264 Páginas.Los diversos y repentinos cambios del entorno vulneran cada vez más la estabilidad de las organizaciones y, en consecuencia, éstas deben estar preparadas para enfrentarlos (capacidad de adaptación e innovación), asumiendo nuevos retos empresariales que si no son bien llevados, pueden influir en el comportamiento de sus colaboradores frente a los nuevos planteamientos de la organización, impactando la moral, la motivación, satisfacción y productividad de los mismos, impidiendo o favoreciendo las modificaciones establecidas, para lo cual se hace necesario la implementación de un cambio cultural. La cultura corporativa, es el efecto de la interacción entre los miembros de una organización en la toma de decisiones para la solución de problemas contextualizados en los hábitos, principios, valores, creencias, reglas y procedimientos que comparten y que se incorporan a la empresa a través de procesos de socialización. No obstante, estos elementos que conforman la cultura vienen a ser el mecanismo por el cual se comunican y se materializan los propósitos, metas y objetivos estratégicos en las organizaciones, por esta razón se hace imprescindible la medición de la cultura como estrategia de mejoramiento continuo, la única opción que tienen las empresas para crecer, permanecer en el tiempo y generar utilidades (Serna, 2016)

    Genetic Modulation of Cerebral Vasculopathy in Children with Sickle Cell Anemia

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    Palestras de difusão da cultura científica dirigidas aos colaboradores internos do INSA, podendo incluir participantes externos envolvidos nos estudos e colegas de investigação da área de trabalho em questão.Sickle cell anemia (SCA) arises from homozygosity for the mutation c.20A>T in the HBB gene which originates hemoglobin S (HbS). In hypoxic conditions, HbS polymerizes inside erythrocytes deforming them and ultimately leading to hemolysis and vaso-occlusion. SCA shows a multifactorial-like behaviour with a high heterogeneity of clinical features, with stroke being the most severe of them. This heterogeneity may arise from underlying genetic modifiers, namely those affecting vascular hemostasis. These include genes like the ones encoding VCAM-1 and its ligand integrin α4 (expressed in activated human endothelium and leucocytes/stress reticulocytes, respectively), but also eNOS (expressed in human endothelium and regulating vascular tone). The aim of this study was to identify putative genetic modulators of stroke risk by analyzing 70 pediatric SCA patients, grouped according to their degree of cerebral vasculopathy. Molecular analysis was performed using Next-Generation Sequencing (NGS) and Sanger Sequencing. R software was used for statistical analyses and association studies. In silico studies were performed using PHASE, TFbind, PROMO and Human Splicing Finder software tools. We identified six different VCAM1 promoter variants and seven haplotypes. The VCAM1 promoter rs1409419_T allele was associated with stroke events, while one VCAM1 promoter haplotype was found to be protective of stroke. In the ITGA4 gene, forty variants were found, six of them novel. All patients presented with at least one variant in this gene. We observed co-inheritance of specific sets of ITGA4 variants indicating the presence of haplotypes not previously described. Three NOS3 variants were analysed and seven haplotypes were identified. The NOS3 promoter rs2070744_C allele was associated with stroke events, while the intron 4 VNTR 27bp_4a allele was found to be in association with risk of stroke. Our results reinforce the role of endothelial molecules and blood cell interaction in SCA severity. The association between specific variants in VCAM1 and ITGA4, as well as in NOS3, with certain cerebral vasculopathy predictors further enhances their putative modulating effect on pediatric stroke severity and prognosis. These findings provide additional clues on the SCA pathophysiology and uncover features of both genes that may prove to be crucial as potential therapeutic targets.N/

    Paediatric cerebral vasculopathy in sickle cell anaemia: contribution of genetic modifiers

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    Sickle cell anaemia (SCA) arises from homozygosity for the mutation c.20A>T in the HBB gene. However, it shows a multifactorial-like behaviour with high heterogeneity of clinical features. Cerebral vasculopathy (CVA), namely paediatric ischemic stroke, is one of its most devastating consequences. The risk of CVA development, specifically stroke or silent cerebral infarction, may be modulated by underlying genetic modifiers, for example those affecting vascular homeostasis. In this study, we aimed to investigate the impact of variants in genes related with endothelial adhesion (VCAM1 and ITGA4) and nitric oxide metabolism (NOS3) on CVA in a group of 70 SCA children well characterized according to their CVA degree. In addition, the effect of the same genetic variants on biochemical/haematological biomarkers of chronic haemolysis was also analysed. Moreover, we also evaluated the putative additional modulating role of variants previously identified as stroke risk factors by genome-wide associated studies: GOLGB1 Y1212C, ENPP1 K173Q and PON1 Q192R. Molecular analysis was performed using PCR, PCR-RFLP, next-generation sequencing and Sanger sequencing. SPSS software was used for statistical analyses and association studies. One of the seven VCAM1 promoter haplotypes found and the VCAM1 promoter rs1409419_T showed association with moderate to high time-averaged mean of maximum velocity in the middle cerebral artery. The same association was observed for the variant ENPP1 K173Q. On the other hand, we observed that ITGA4 variants rs113276800_A and rs3770138_T were associated with stroke events. As for NOS3, one of the six haplotypes and the intron 4 VNTR_4b allele (5 repeats) were associated with lower risk of silent cerebral infarction. Chronic haemolysis biomarker levels also seemed to be influenced by genetic variants. LDH levels was higher in the presence of VCAM1 promoter rs1409419_T and one VCAM1 haplotype but lower in patients with one of the two ITGA4 haplotypes found. Genetic modulation also occurred in total bilirubin levels, which were higher in association with VCAM1 rs3783613_C allele. Our results, namely the association between specific variants with certain cerebral vasculopathy predictors further enhances their putative modulating effect on SCA paediatric stroke risk, severity and prognosis. These findings provide additional clues on the SCA pathophysiology and uncover features in these genes that may prove to be crucial as potential therapeutic targets.INSA_202DGH720 and ISAMBinfo:eu-repo/semantics/publishedVersio

    Genetic modulation of stroke in children with sickle cell anaemia

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    Sickle cell anaemia (SCA) is an autosomal recessive genetic disease that leads to the synthesis of haemoglobin S (HbS). The pathophysiology of the disease is centred on HbS polymerization inside the red blood cells, which become sickle-shaped (SSRBCs), rigid, viscous and adherent-prone to the vascular endothelium, favouring the occurrence of chronic haemolysis and vaso-occlusion. The main vascular problems of SCA arise from several pathways including endothelial dysfunction and nitric oxide (NO) metabolism. Children with SCA have a much higher risk (11% by age 20 years) of developing stroke or silent cerebral infarcts (up to 37%) than the general paediatric population. Abnormal interactions between SSRBCs and the cerebral arterial endothelium lead to endothelial injury, vaso-occlusion and tissue ischemia and result in cerebral vasculopathy (CVA) through a yet unknown pathophysiological mechanism. Current risk screening strategies rely mainly on imaging techniques (transcranial Doppler ultrasonography and magnetic resonance imaging) and children with altered results undergo regular blood transfusion and/or hydroxyurea therapy to reduce stroke risk/recurrence. However, we need more specific/sensitive biomarkers for stroke prediction/prognosis. Genetic modulators may be paramount in SCA pathophysiology and in CVA severity. They include variants in VCAM1 (endothelial dysfunction), ITGA4 (cell-cell adhesion), and NOS3 (nitric oxide metabolism. The main goals of this work are: a) improve the knowledge on the genetic architecture of paediatric cerebral vasculopathy in SCA; b) assessing the consequences of those genetic variants on gene expression/protein function; c) identify genotypic/phenotypic markers of SCA sub-phenotypes; and d) analyse their potential as genetic modulators of disease severity. This would be crucial in assessing potential pharmacological targets specifically aimed to the vascular system and instrumental for the design of novel preventive, prophylactic or therapeutic strategies.INSA_202DGH72 and ISAMBN/

    Fetal hemoglobin level and stroke risk in children with sickle cell anemia

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    21ª Reunião da Sociedade Portuguesa de Genética Humana, 16-18 nov 2017Sickle Cell Anemia (SCA) is a hereditary anemia caused by a missense mutation in HBB and it is characterized by chronic hemolysis, recurrent episodes of vaso-occlusion and infection. Cerebral vasculopathy is one of the most devastating complications of the disease and even young children with SCA have a high risk of stroke. It is known that both environmental and genetic determinants are able to modulate the onset, course and outcome of the disease. Among those, the level of fetal hemoglobin (HbF) has been proposed as the most significant disease modulator. Thus, in this work, we aimed to investigate if the level of HbF in SCA children is related with the risk of stroke and if it is modulated by variants in genes, such as HBG2, BCL11A, HBS1L-MYB, and KLF1. Sixty-seven children (3 years of age) with SCA were enrolled in this study. Hematological and imaging data were retrospectively obtained from patients’ medical records at Greater Lisbon area hospitals. Patients were grouped according to their degree of cerebral vasculopathy evaluated by transcranial Doppler velocities and magnetic resonance imaging. Molecular analyses were performed using Next-Generation Sequencing, Sanger sequencing and PCR-RFLP. In silico studies and statistical analyses were done using the PolyPhen-2 and SPSS softwares, respectively. The association studies revealed that low HbF levels were associated with stroke events in SCA children (p=0.005). At the molecular level, it was observed that patients with the rarest genotypes in HBG2 (rs7482144_TT+TC) presented higher levels of HbF (p=0.031). Additionally, the rs11886868_C and the rs4671393_A alleles in BCL11A also seemed to predispose to higher HbF levels. Moreover, eleven distinct variants in KLF1 were detected (one of them novel, the p.Q342H) with 83% of the patients having at least one variant in this gene. The group of patients who have co-inherited the above mentioned variants in HBG2 and BCL11A together with at least one KLF1 variant presented the highest HbF levels (p=0.021). Our results corroborate previous studies suggesting that a low level of HbF in SCA patients is a risk factor for stroke. Furthermore, we report for the first time the importance of KLF1 variants in combination with other genetic modifiers to the final phenotypic expression of HbF in SCA children with different degrees of cerebral vasculopathy. Consequently, this study allowed the delineation of a genetic pattern with prognostic value for SCA.info:eu-repo/semantics/publishedVersio

    Is the reason to switch relevant?

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    57763]. AS is supported by a doctoral grant from “Fundação para a Ciência e Tecnologia” (SFRH/BD/108246/2015).Background: To investigate whether the reason to discontinue the first TNF inhibitor (TNFi) affects the response to the second TNFi in axial spondyloarthritis (axSpA). Methods: Patients with axSpA from the Rheumatic Diseases Portuguese Register (ReumaPt), who discontinued their first TNFi and started the second TNFi between June 2008 and May 2018, were included. Response was assessed by the Ankylosing Spondylitis Disease Activity Score (ASDAS) clinically important improvement (ASDAS-CII), major important improvement (ASDAS-MI), low disease activity (ASDAS-LDA), and inactive disease (ASDAS-ID). The reason for discontinuation of the first TNFi was defined, according to ASDAS-CII as primary failure (no response ≤ 6 months), secondary failure (response ≤ 6 months but lost thereafter), adverse events, and others. The association between the reason for discontinuation of the first TNFi and response to the second TNFi over time was assessed in multivariable generalized equation (GEE) models. Results: In total, 193 patients were included. The reason for discontinuation of the first TNFi did not influence the response to the second TNFi, according to the ASDAS-CII. However, a difference was found with more stringent outcomes, e.g., there was a higher likelihood to achieve ASDAS-ID with the second TNFi for patients discontinuing the first TNFi due to secondary failure (OR 7.3 [95%CI 1.9; 27.7]), adverse events (OR 9.1 [2.5; 33.3]), or other reasons (OR 7.7 [1.6; 37.9]) compared to primary failure. Conclusion: Patients with axSpA with secondary failure to their first TNFi, compared to those with primary failure, have a better response to the second TNFi according to stringent outcomes.publishersversionpublishe

    Endothelial factors and stroke risk in pediatric sickle cell anemia patients: insights from VCAM1 and ITGA4 variants

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    Sickle cell anemia (SCA) arises from homozygosity for the mutation c.20A>T in the HBB gene which originates hemoglobin S (HbS). In hypoxic conditions, HbS polymerizes inside erythrocytes deforming them and ultimately leading to hemolysis and vaso-occlusion. SCA shows a multifactorial-like behaviour with a high heterogeneity of clinical features, with stroke being the most severe of them. This heterogeneity may arise from underlying genetic modifiers, namely those affecting vascular adhesion/endothelial dysfunction. These include genes encoding the VCAM-1 molecule and its ligand VLA-4 (ITGA4 or integrin α4), increasingly studied due to their expression in activated human endothelium and leucocytes/stress reticulocytes, respectively. The aim of this study was to identify putative genetic modulators of stroke risk by analyzing 70 pediatric SCA patients, grouped according to their degree of cerebral vasculopathy. Molecular analysis was performed using Next-Generation Sequencing (NGS) and Sanger Sequencing. R software was used for statistical analyses and association studies. In silico studies were performed using PHASE, TFbind, PROMO and Human Splicing Finder software tools. We identified six different VCAM1 promoter variants and seven haplotypes. The VCAM1 promoter rs1409419_T allele was associated with stroke events (p=0.008; O.R.= 4.33; C.I.95% =1.391-14.257), while one VCAM1 promoter haplotype was found to be protective of stroke (p=0.011; O.R.=0.22; C.I.95% =0.048-0.784). On the ITGA4 gene, forty variants were found, six of them novel. All patients presented with at least one variant in this gene. We observed co-inheritance of specific sets of ITGA4 variants indicating the presence of haplotypes not previously described. Additionally the presence of specific variants seems to result in a predisposition for either high reticulocyte count, elevated lactate dehydrogenase, raised bilirubin levels or increased transcranial Doppler velocity values. Our results reinforce the role of endothelial molecules and blood cell interaction in SCA severity. The association between specific VCAM1, as well as ITGA4, variants with certain cerebral vasculopathy predictors, further enhances their putative modulating effect on pediatric stroke severity and prognosis. These findings provide additional clues on the SCA pathophysiology and uncover features of both genes that may prove to be crucial as potential therapeutic targets.info:eu-repo/semantics/publishedVersio

    Hurdles and opportunities in implementing marine biosecurity systems in data-poor regions

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    Managing marine nonindigenous species (mNIS) is challenging, because marine environments are highly connected, allowing the dispersal of species across large spatial scales, including geopolitical borders. Cross-border inconsistencies in biosecurity management can promote the spread of mNIS across geopolitical borders, and incursions often go unnoticed or unreported. Collaborative surveillance programs can enhance the early detection of mNIS, when response may still be possible, and can foster capacity building around a common threat. Regional or international databases curated for mNIS can inform local monitoring programs and can foster real-time information exchange on mNIS of concern. When combined, local species reference libraries, publicly available mNIS databases, and predictive modeling can facilitate the development of biosecurity programs in regions lacking baseline data. Biosecurity programs should be practical, feasible, cost-effective, mainly focused on prevention and early detection, and be built on the collaboration and coordination of government, nongovernment organizations, stakeholders, and local citizens for a rapid response.This work resulted from a workshop organized at the King Abdul- lah University of Science and Technology and sponsored under the Support for Conferences and Workshops Program. We would like to thank the admin support of the Red Sea Research Cen- ter team, IT, and teachers and students from the KAUST schools who participated in some outreach activities. We thank Ana Bi- gio for the artwork presented in this article (figures 1–4). GS was supported by the European Social Fund, under project no 09.3.3- LMT-K-712, the “Development of Competences of Scientists, other Researchers and Students through Practical Research Activities” measure, grant agreement no. 09.3.3-LMT-K-712–19-0083

    Viral genetic clustering and transmission dynamics of the 2022 mpox outbreak in Portugal

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    Pathogen genome sequencing during epidemics enhances our ability to identify and understand suspected clusters and investigate their relationships. Here, we combine genomic and epidemiological data of the 2022 mpox outbreak to better understand early viral spread, diversification and transmission dynamics. By sequencing 52% of the confirmed cases in Portugal, we identified the mpox virus sublineages with the highest impact on case numbers and fitted them into a global context, finding evidence that several international sublineages probably emerged or spread early in Portugal. We estimated a 62% infection reporting rate and that 1.3% of the population of men who have sex with men in Portugal were infected. We infer the critical role played by sexual networks and superspreader gatherings, such as sauna attendance, in the dissemination of mpox virus. Overall, our findings highlight genomic epidemiology as a tool for the real-time monitoring and control of mpox epidemics, and can guide future vaccine policy in a highly susceptible population.info:eu-repo/semantics/publishedVersio

    SARS-CoV-2 introductions and early dynamics of the epidemic in Portugal

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    Genomic surveillance of SARS-CoV-2 in Portugal was rapidly implemented by the National Institute of Health in the early stages of the COVID-19 epidemic, in collaboration with more than 50 laboratories distributed nationwide. Methods By applying recent phylodynamic models that allow integration of individual-based travel history, we reconstructed and characterized the spatio-temporal dynamics of SARSCoV-2 introductions and early dissemination in Portugal. Results We detected at least 277 independent SARS-CoV-2 introductions, mostly from European countries (namely the United Kingdom, Spain, France, Italy, and Switzerland), which were consistent with the countries with the highest connectivity with Portugal. Although most introductions were estimated to have occurred during early March 2020, it is likely that SARS-CoV-2 was silently circulating in Portugal throughout February, before the first cases were confirmed. Conclusions Here we conclude that the earlier implementation of measures could have minimized the number of introductions and subsequent virus expansion in Portugal. This study lays the foundation for genomic epidemiology of SARS-CoV-2 in Portugal, and highlights the need for systematic and geographically-representative genomic surveillance.We gratefully acknowledge to Sara Hill and Nuno Faria (University of Oxford) and Joshua Quick and Nick Loman (University of Birmingham) for kindly providing us with the initial sets of Artic Network primers for NGS; Rafael Mamede (MRamirez team, IMM, Lisbon) for developing and sharing a bioinformatics script for sequence curation (https://github.com/rfm-targa/BioinfUtils); Philippe Lemey (KU Leuven) for providing guidance on the implementation of the phylodynamic models; Joshua L. Cherry (National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health) for providing guidance with the subsampling strategies; and all authors, originating and submitting laboratories who have contributed genome data on GISAID (https://www.gisaid.org/) on which part of this research is based. The opinions expressed in this article are those of the authors and do not reflect the view of the National Institutes of Health, the Department of Health and Human Services, or the United States government. This study is co-funded by Fundação para a Ciência e Tecnologia and Agência de Investigação Clínica e Inovação Biomédica (234_596874175) on behalf of the Research 4 COVID-19 call. Some infrastructural resources used in this study come from the GenomePT project (POCI-01-0145-FEDER-022184), supported by COMPETE 2020 - Operational Programme for Competitiveness and Internationalisation (POCI), Lisboa Portugal Regional Operational Programme (Lisboa2020), Algarve Portugal Regional Operational Programme (CRESC Algarve2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF), and by Fundação para a Ciência e a Tecnologia (FCT).info:eu-repo/semantics/publishedVersio
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