1,720,961 research outputs found
Efeitos da N(épsilon)-(carboximetil)lisina (CML), um produto final de glicação avançada (PFGA), na doença falciforme
No full textA doença falciforme (DF) caracteriza-se pela presença da hemoglobina S, que pode estar em homozigose (HbSS), como na anemia falciforme (AF), bem como em associação com outras hemoglobinas variantes ou talassemias, como na doença SC (HbSC). A HbS forma agregados em estado de desoxigenação, com consequente rigidez eritrocitária, fatores que contribuem para alterações na microvasculatura, resultando em vaso-oclusão, isquemia tecidual, lesão de órgãos, eventos dolorosos e compromentimento crônico de vários orgãos e sistemas. A gravidade da vaso-oclusão e a progressão para isquemia do órgão terminal são potencializadas pelo estresse oxidativo, sendo que os produtos finais de glicação avançada (PFGAs), tais como N(épsilon)carboximetilisina (CML), constituem marcadores desse processo de oxidação. -OBJETIVO: O objetivo geral do presente estudo foi determinar os níveis de CMLs no soro de pacientes com DF (HbSS e HbSC), bem como associar essas concentrações a biomarcadores laboratoriais e genéticos, bem como ao tratamento com a hidroxiuréia (HU). MATERIAIS E MÉTODOS: Os testes hematológicos foram realizados em contador de células automatizado; os marcadores bioquímicos foram mensurados no soro por ensaio de imunoquímica. Os perfiis de hemoglobina foram confirmados por cromatografia líquida de alta eficiência (HPLC). Os haplótipos associados ao grupo de genes da globina beta S (HBB S) e genes da globina beta C (HBB C) foram investigados por reação em cadeia da polimerase, seguida da análise de polimorfismos de comprimento de fragmentos de restrição (RFLP). Os níveis séricos de CML foram avaliados por ELISA competitivo. As análises estatísticas foram realizadas utilizando-se os softwares SPSS e GraphPad, considerando p≤0,05 como estatisticamente significante. RESULTADOS: O presente estudo demonstra a existência de características laboratoriais distintas nos indivíduos com AF em tratamento com HU em comparação aos sem tratamento. Em resumo, o estudo demonstrou que o tratamento com HU reduziu a anemia hemolítica aguda e as crises vaso-oclusivas. Em relação aos níveis de CML, foi demonstrado que os indivíduos com AF apresentaram concentrações mais elevadas no soro, em comparação aos controles saudáveis (HbAA). Foi identificada a correlação significativa entre alanina aminotransferase (ALT) e CML. Demonstrou ainda que a CML está associada ao haplótipo βS em pacientes com AF e evidenciou que os níveis de CML estiveram mais elevados nos pacientes com doença SC em comparação com os controles saudáveis e também revelou anemia hemolítica, crises de dor e hipocolesterolemia em pacientes com HbSC em comparação com o controle saudável. CONCLUSÃO: Nossos resultados sugerem que a HU parece influenciar a inflamação, hemólise e função hepática dos pacientes com AF. As evidências do presente estudo sugerem a possibilidade de que os CMLs tenham papel na patologia da DF, com associação aos haplótipos
da globina beta, nas complicações presentes na AF, mas que os seus níveis séricos não são influenciados pelo tratamento com HU.CNPq, FAPESB, FIOCRUZ-IGMSickle cell disease (SCD) is characterized by the presence of hemoglobin S, which may be homozygous (HbSS), like in sickle cell anemia (SCA), as well as in association with other variant hemoglobins or thalassemias, such as SC (HbSC). HbS forms aggregates in a state of deoxygenation, with consequent erythrocyte rigidity, factor that contribute to changes in the microvasculature, resulting in vaso-occlusion, tissue ischemia, organ damage, pain and chronic compromise of various organs and systems. The severity of the vaso-occlusion and progression to end organ ischemia is potentiated by oxidative stress and advanced glycation end-products (AGEs) such as N(epsilon)-carboxymethylisine (CML) have been demonstrated to be markers of oxidative stress. OBJECTIVE: The general objective of the present study was to determine serum CML levels in patients with SCD (HbSS and HbSC), as well as to associate their concentrations with laboratory and genetic biomarkers, as well as with hydroxyurea (HU) treatment. MATERIALS AND METHODS: Hematological tests were performed in an automated cell counter; the biochemical markers were measured in the serum by immunochemistry assay. Hemoglobin profiles were confirmed by high performance liquid chromatography (HPLC). The haplotypes associated with the beta globin gene cluster (HBB S) and beta globin C (HBB C) genes were investigated by polymerase chain reaction, followed by restriction fragment length polymorphism (RFLP) analysis. Serum levels of CML were evaluated by competitive ELISA. Statistical analyzes were performed using the software SPSS and GraphPad, considering p ≤ 0.05 as statistically significant. RESULTS: The present study demonstrates the existence of distinct laboratory characteristics in individuals with SCA on HU treatment compared to those without treatment. In summary, the study demonstrated that treatment with HU reduced acute hemolytic anemia and vaso-occlusive crises. Regarding CML levels, individuals with SCA presented higher serum concentrations than healthy controls (HbAA). Significant correlation between alanine aminotransferase (ALT) and CML was identified. It also showed that CML is associated with βS haplotype in patients with SCA and that CML levels were higher in patients with SC disease compared to healthy controls. Hemolytic anemia, pain crises and hypocholesterolemia were identified in individuals with HbSC compared to healthy control. CONCLUSION: Our results suggest that HU plays a significant role in inflammation, hemolysis, and hepatic systems in sickle cell anemia. The evidences of the present study suggest the possibility that CMLs have a role in the pathology of SCD. It also suggests an association between CML and SCA haplotypes, and has shown that CML has a role to play in the complications of SCA that is not influenced by HU treatment.2021-07-0
Efeitos da N(épsilon)-(carboximetil)lisina (CML), um produto final de glicação avançada (PFGA), na doença falciforme
No full textCNPq, FAPESB, FIOCRUZ-IGMFundação Oswaldo Cruz. Instituto Gonçalo Moniz. Salvador, BA, Brasil.A doença falciforme (DF) caracteriza-se pela presença da hemoglobina S, que pode estar em homozigose (HbSS), como na anemia falciforme (AF), bem como em associação com outras hemoglobinas variantes ou talassemias, como na doença SC (HbSC). A HbS forma agregados em estado de desoxigenação, com consequente rigidez eritrocitária, fatores que contribuem para alterações na microvasculatura, resultando em vaso-oclusão, isquemia tecidual, lesão de órgãos, eventos dolorosos e compromentimento crônico de vários orgãos e sistemas. A gravidade da vaso-oclusão e a progressão para isquemia do órgão terminal são potencializadas pelo estresse oxidativo, sendo que os produtos finais de glicação avançada (PFGAs), tais como N(épsilon)carboximetilisina (CML), constituem marcadores desse processo de oxidação. -OBJETIVO: O objetivo geral do presente estudo foi determinar os níveis de CMLs no soro de pacientes com DF (HbSS e HbSC), bem como associar essas concentrações a biomarcadores laboratoriais e genéticos, bem como ao tratamento com a hidroxiuréia (HU). MATERIAIS E MÉTODOS: Os testes hematológicos foram realizados em contador de células automatizado; os marcadores bioquímicos foram mensurados no soro por ensaio de imunoquímica. Os perfiis de hemoglobina foram confirmados por cromatografia líquida de alta eficiência (HPLC). Os haplótipos associados ao grupo de genes da globina beta S (HBB S) e genes da globina beta C (HBB C) foram investigados por reação em cadeia da polimerase, seguida da análise de polimorfismos de comprimento de fragmentos de restrição (RFLP). Os níveis séricos de CML foram avaliados por ELISA competitivo. As análises estatísticas foram realizadas utilizando-se os softwares SPSS e GraphPad, considerando p≤0,05 como estatisticamente significante. RESULTADOS: O presente estudo demonstra a existência de características laboratoriais distintas nos indivíduos com AF em tratamento com HU em comparação aos sem tratamento. Em resumo, o estudo demonstrou que o tratamento com HU reduziu a anemia hemolítica aguda e as crises vaso-oclusivas. Em relação aos níveis de CML, foi demonstrado que os indivíduos com AF apresentaram concentrações mais elevadas no soro, em comparação aos controles saudáveis (HbAA). Foi identificada a correlação significativa entre alanina aminotransferase (ALT) e CML. Demonstrou ainda que a CML está associada ao haplótipo βS em pacientes com AF e evidenciou que os níveis de CML estiveram mais elevados nos pacientes com doença SC em comparação com os controles saudáveis e também revelou anemia hemolítica, crises de dor e hipocolesterolemia em pacientes com HbSC em comparação com o controle saudável. CONCLUSÃO: Nossos resultados sugerem que a HU parece influenciar a inflamação, hemólise e função hepática dos pacientes com AF. As evidências do presente estudo sugerem a possibilidade de que os CMLs tenham papel na patologia da DF, com associação aos haplótipos
da globina beta, nas complicações presentes na AF, mas que os seus níveis séricos não são influenciados pelo tratamento com HU.Sickle cell disease (SCD) is characterized by the presence of hemoglobin S, which may be homozygous (HbSS), like in sickle cell anemia (SCA), as well as in association with other variant hemoglobins or thalassemias, such as SC (HbSC). HbS forms aggregates in a state of deoxygenation, with consequent erythrocyte rigidity, factor that contribute to changes in the microvasculature, resulting in vaso-occlusion, tissue ischemia, organ damage, pain and chronic compromise of various organs and systems. The severity of the vaso-occlusion and progression to end organ ischemia is potentiated by oxidative stress and advanced glycation end-products (AGEs) such as N(epsilon)-carboxymethylisine (CML) have been demonstrated to be markers of oxidative stress. OBJECTIVE: The general objective of the present study was to determine serum CML levels in patients with SCD (HbSS and HbSC), as well as to associate their concentrations with laboratory and genetic biomarkers, as well as with hydroxyurea (HU) treatment. MATERIALS AND METHODS: Hematological tests were performed in an automated cell counter; the biochemical markers were measured in the serum by immunochemistry assay. Hemoglobin profiles were confirmed by high performance liquid chromatography (HPLC). The haplotypes associated with the beta globin gene cluster (HBB S) and beta globin C (HBB C) genes were investigated by polymerase chain reaction, followed by restriction fragment length polymorphism (RFLP) analysis. Serum levels of CML were evaluated by competitive ELISA. Statistical analyzes were performed using the software SPSS and GraphPad, considering p ≤ 0.05 as statistically significant. RESULTS: The present study demonstrates the existence of distinct laboratory characteristics in individuals with SCA on HU treatment compared to those without treatment. In summary, the study demonstrated that treatment with HU reduced acute hemolytic anemia and vaso-occlusive crises. Regarding CML levels, individuals with SCA presented higher serum concentrations than healthy controls (HbAA). Significant correlation between alanine aminotransferase (ALT) and CML was identified. It also showed that CML is associated with βS haplotype in patients with SCA and that CML levels were higher in patients with SC disease compared to healthy controls. Hemolytic anemia, pain crises and hypocholesterolemia were identified in individuals with HbSC compared to healthy control. CONCLUSION: Our results suggest that HU plays a significant role in inflammation, hemolysis, and hepatic systems in sickle cell anemia. The evidences of the present study suggest the possibility that CMLs have a role in the pathology of SCD. It also suggests an association between CML and SCA haplotypes, and has shown that CML has a role to play in the complications of SCA that is not influenced by HU treatment.2021-07-0
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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