Targeting Heme with Single Domain Antibodies

Heme, i.e. iron (Fe) protoporphyrin IX, functions as a prosthetic group in a variety of hemoproteins that participate in vital biologic functions essential to sustain life. Heme is a highly reactive molecule, participating in redox reactions, and presumably for this reason it must be sequestered within the heme pockets of hemoproteins, controlling its reactivity. However, under biological stress conditions, hemoproteins can release their prosthetic groups, generating “free heme”, which binds loosely to proteins or to other molecules and presumably acquires unfettered redox activity. Moreover, a growing body of evidence supports the notion that “free heme” can act in a vasoactive, pro-inflammatory and cytotoxic manner when released from a subset of these hemoproteins, such as extracellular hemoglobin, generated during hemolytic conditions. (...

Heme Cytotoxicity and the Pathogenesis of Immune-Mediated Inflammatory Diseases

Heme, iron (Fe) protoporphyrin IX, functions as a prosthetic group in a range of hemoproteins essential to support life under aerobic conditions. The Fe contained within the prosthetic heme groups of these hemoproteins can catalyze the production of reactive oxygen species. Presumably for this reason, heme must be sequestered within those hemoproteins, thereby shielding the reactivity of its Fe-heme. However, under pathologic conditions associated with oxidative stress, some hemoproteins can release their prosthetic heme groups. While this heme is not necessarily damaging per se, it becomes highly cytotoxic in the presence of a range of inflammatory mediators such as tumor necrosis factor. This can lead to tissue damage and, as such, exacerbate the pathologic outcome of several immune-mediated inflammatory conditions. Presumably, targeting “free heme” may be used as a therapeutic intervention against these diseases

The alternative oxidase family of Vitis vinifera reveals an attractive model to study the importance of genomic design

'Genomic design' refers to the structural organization of gene sequences. Recently, the role of intron sequences for gene regulation is being better understood. Further, introns possess high rates of polymorphism that are considered as the major source for speciation. In molecular breeding, the length of gene-specific introns is recognized as a tool to discriminate genotypes with diverse traits of agronomic interest. 'Economy selection' and 'time-economy selection' have been proposed as models for explaining why highly expressed genes typically contain small introns. However, in contrast to these theories, plant-specific selection reveals that highly expressed genes contain introns that are large. In the presented research, 'wet'Aox gene identification from grapevine is advanced by a bioinformatics approach to study the species-specific organization of Aox gene structures in relation to available expressed sequence tag (EST) data. Two Aox1 and one Aox2 gene sequences have been identified in Vitis vinifera using grapevine cultivars from Portugal and Germany. Searching the complete genome sequence data of two grapevine cultivars confirmed that V. vinifera alternative oxidase (Aox) is encoded by a small multigene family composed of Aox1a, Aox1b and Aox2. An analysis of EST distribution revealed high expression of the VvAox2 gene. A relationship between the atypical long primary transcript of VvAox2 (in comparison to other plant Aox genes) and its expression level is suggested. V. vinifera Aox genes contain four exons interrupted by three introns except for Aox1a which contains an additional intron in the 3'-UTR. The lengths of primary Aox transcripts were estimated for each gene in two V. vinifera varieties: PN40024 and Pinot Noir. In both varieties, Aox1a and Aox1b contained small introns that corresponded to primary transcript lengths ranging from 1501 to 1810 bp. The Aox2 of PN40024 (12 329 bp) was longer than that from Pinot Noir (7279 bp) because of selection against a transposable-element insertion that is 5028 bp in size. An EST database basic local alignment search tool (BLAST) search of GenBank revealed the following ESTs percentages for each gene: Aox1a (26.2%), Aox1b (11.9%) and Aox2 (61.9%). Aox1a was expressed in fruits and roots, Aox1b expression was confined to flowers and Aox2 was ubiquitously expressed. These data for V. vinifera show that atypically long Aox intron lengths are related to high levels of gene expression. Furthermore, it is shown for the first time that two grapevine cultivars can be distinguished by Aox intron length polymorphism

Obesity, acute kidney injury and mortality in patients with sepsis: a cohort analysis

Although the prognostic effect of obesity has been studied in critically ill patients its impact on outcomes of septic patients and its role as a risk factor for acute kidney injury (AKI) is not consensual. We aimed to analyze the impact of obesity on the occurrence of AKI and on in-hospital mortality in a cohort of critically ill septic patients. This study is retrospective including 456 adult patients with sepsis admitted to the Division of Intensive Medicine of the Centro Hospitalar Lisboa Norte (Lisbon, Portugal) between January 2008 and December 2014. Obesity was defined as a body mass index of 30 kg/m2 or higher. The Kidney Disease Improving Global Outcomes classification was used to diagnose and classify patients developing AKI. AKI occurred in 87.5% of patients (19.5% with stage 1, 22.6% with stage 2 and 45.4% with stage 3). Obese patients developed AKI more frequently than non-obese patients (92.8% versus 85.5%, p = .035; unadjusted OR 2.2 (95% CI: 1.04-4.6), p = .039; adjusted OR 2.31 (95% CI: 1.07-5.02), p = .034). The percentage of obese patients, however, did not differ between AKI stages (stage 1, 25.1%; stage 2, 28.6%; stage 3, 15.4%; p = .145). There was no association between obesity and mortality (p = .739). Of note, when comparing AKI patients with or without obesity in terms of in-hospital mortality there were also no significant differences between those groups (38.4% versus 38.4%, p = .998). Obesity was associated with the occurrence of AKI in critically ill patients with sepsis; however, it was not associated with in-hospital mortality.info:eu-repo/semantics/publishedVersio

Prevalência de anticorpos contra o vírus da língua azul em ovinos do Distrito Federal

The aims of the present study were to determine the prevalence of bluetongue virus antibodies in sheep from Distrito Federal. Sera from 606 sheep of 18 herds were submitted to the agar-gel immunodiffusion for bluetongue virus antibodies. The prevalences of bluetongue infection found in Distrito Federal were 100% (CI 95%: 84.67 to 100.00) for flocks and 52.37% (389/606) (CI 95%: 35.76 to 68.98) for animals. Thus, data from the present study showed that infection by bluetongue virus is highly widespread in sheep flocks in the Distrito Federal, which intensifies the need for assessments on the impact of this disease in Brazil. ________________________________________________________________________________________________________ RESUMOO objetivo deste trabalho foi estimar a prevalência de anticorpos contra o vírus da língua azul (BTV) em rebanhos ovinos do Distrito Federal. Soros de 606 ovinos, pertencentes a 18 propriedades, foram analisados pela técnica de imunodifusão em ágar gel (AGID), para pesquisa de anticorpos contra o BTV. As prevalências de rebanhos e de animais infectados pelo vírus da língua azul no Distrito Federal foram respectivamente de 100% (IC 95%: 84,67% a 100%) e de 52,37% (389/606) (IC 95%: 35,76% a 68,98%). Assim, o presente estudo permite concluir que o vírus da língua azul está amplamente disseminada no rebanho ovino do Distrito Federal

Protocolo de Adecuación de urgencias hospitalarias: tradução e adaptação para a cultura brasileira

Objetivo: Traduzir e adaptar culturalmente o Protocolo de Adecuación de Urgencias Hospitalarias (PAUH) para o português do Brasil.Método: Estudo metodológico, desenvolvido no período de 2019 a 2021, em hospital de urgência, e que seguiu as etapas de tradução, síntese das traduções, retrotradução, revisão por comitê de experts, pré-teste e submissão aos autores do protocolo. A amostra incluiu quatro tradutores, cinco experts, que avaliaram equivalência conceitual, semântica, cultural e idiomática, 21 enfermeiros e nove médicos, que participaram do pré-teste. Utilizou-se Indíce de Validade de Conteúdo (IVC), alfa de Cronbach e concordância de Kendall.Resultados: A versão final da adaptação apresentou IVC que variou de 0,40 a 1,0. A consistência interna evidenciou Equivalência Semântica (α=0,815), Equivalência Idiomática (α=0,924) e Equivalência Conceitual (α=0,71), com valores aceitáveis. A concordância de Kendall revelou boa confiabilidade (W=0,14-0,58).Conclusão: O processo de tradução e adaptação cultural do PAUH originou instrumento aplicável ao contexto brasileiro. Palavras-chave: Urgências. Triagem. Protocolos. Tradução. Estudo de validação

Characterization of Plasma Labile Heme in Hemolytic Conditions

The deposited article is the accepted manuscript (post-print version) posted online 7 August 2017 and provided by The Febs Journal. This article has been accepted for publication and undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record. The deposited article version contains attached the supplementary materials within the pdf. This publication hasn't any creative commons license associated, although it is in open access.Extracellular hemoglobin (Hb), a byproduct of hemolysis, can release its prosthetic heme groups upon oxidation. This produces metabolically active heme that is exchangeable between acceptor proteins, macromolecules and low molecular weight ligands, termed here labile heme. As it accumulates in plasma labile heme acts in a pro-oxidant manner and regulates cellular metabolism while exerting pro-inflammatory and cytotoxic effects that foster the pathogenesis of hemolytic diseases. Here we developed and characterized a panel of heme-specific single domain antibodies (sdAbs) that together with a cellular-based heme reporter assay, allow for quantification and characterization of labile heme in plasma during hemolytic conditions. Using these approaches we demonstrate that labile heme generated during hemolytic conditions is bound to plasma molecules with an affinity higher than 10(-7) M and that 2-8% (~2-5 μM) of the total amount of heme detected in plasma can be internalized by bystander cells, i.e. bioavailable heme. Acute, but not chronic, hemolysis is associated with transient reduction of plasma heme binding capacity (HBC1/2 ), that is, the ability of plasma molecules to bind labile heme with an affinity higher than 10(-7) M. The heme-specific sdAbs neutralize the pro-oxidant activity of soluble heme in vitro, suggesting that these maybe used to counter the pathologic effects of labile heme during hemolytic conditions. Finally, we show that heme-specific sdAbs can be used to visualize cellular heme. In conclusion, we describe a panel of heme-specific sdAbs that when used with other approaches provide novel insights to the pathophysiology of heme. This article is protected by copyright. All rights reserved.Fundação para a Ciência e Tecnologia grants: (RECI-IMI-IMU-0038-2012, PTDC/SAU-TOX/116627/2010, HMSP-ICT/0018/2011, SFRH/BD/44828/2008, SFRH/BPD/47477/2008, PTDC/SAU-FAR/119173/2010, IF/01010/2013/CP1183/CT0001); ERC grants: (ERC-2011-AdG 294709-DAMAGECONTROL); NHMRC Senior Principal Research Fellowship: (1003484).info:eu-repo/semantics/acceptedVersio

ACIDENTES COM MOTOCICLETAS: CARACTERÍSTICAS DA OCORRÊNCIA E SUSPEITA DO USO DE ÁLCOOL

Se objetivó analizar la relación entre las características de accidentes motociclísticos y la sospecha de consumo alcohólico. Estudio descriptivo, transversal, realizado con 110 pacientes víctimas de accidentes en motocicleta atendidos en hospital de referencia en emergencias de una capital del noreste de Brasil. Datos recolectados en noviembre y diciembre de 2016, analizados mediante estadística descriptiva, aplicándose tests inferenciales. Se verificaron asociaciones significativas entre consumo de alcohol y la condición de la víctima en el vehículo, habilitación, turno del accidente y uso de casco. Las víctimas sin casco y que consumieron alcohol presentaron mayor prevalencia entre los accidentados. Los datos alertan sobre la relevancia de una fiscalización directa, efectiva y continúan por parte de los organismos de tránsito, tomándose en consideración la insuficiencia de medidas preventivas para accidentes.Objetivou-se analisar a relação entre as características dos acidentes motociclísticos e a suspeita do uso de álcool. Estudo descritivo e transversal, realizado com 110 pacientes vítimas de acidentes de motocicleta atendidos em hospital de referência em urgência em uma capital do nordeste do Brasil, cujos dados foram coletados em novembro e dezembro de 2016, e analisados por meio da estatística descritiva, aplicando-se testes inferenciais. Verificou-se associações significativas entre o uso de álcool e a condição da vítima no veículo, habilitação, turno do acidente e uso de capacete. Vítimas sem capacete e que consumiram bebidas alcoólicas apresentaram prevalência maior dentre os acidentados. Os dados alertam sobre a relevância de uma fiscalização direta, efetiva e contínua por parte dos órgãos de trânsito, levando-se em consideração a insuficiência de medidas preventivas para acidentes.The present study aimed to analyze the relationship between the characteristics of motorcycle accidents and suspected alcohol use. Descriptive and cross-sectional study with 110 patients involved in motorcycle accidents assisted at an emergency hospital in a large city (state capital) in Northeastern Brazil. Data was collected in November-December 2016 and analyzed through descriptive statistics and inferential tests. Significant associations were found between alcohol consumption and injury severity, licensed or unlicensed drivers, time of the accident (night or day) and helmet use. Most victims of motorcycle accidents were not using a helmet and had consumed alcoholic beverages. The findings call attention to the need for a direct, effective and sustainable traffic crash surveillance system by the responsible bodies, given the lack of effective preventive measures

Renal control of disease tolerance to malaria

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Serum lactates and acute kidney injury in patients with sepsis: A cohort analysis

Granting the association of lactates with mortality has been largely documented in critically ill patients with sepsis, its association with the development of acute kidney injury (AKI) in this setting is not well established. We aimed to analyze the association of serum lactates at intensive care unit (ICU) admission with the occurrence AKI in a cohort of critically ill septic patients. Materials and methods: This study is retrospective including 457 adult patients with sepsis admitted to the Division of Intensive Medicine of the Centro Hospitalar Lisboa Norte (Lisbon, Portugal) between January 2008 and December 2014. The Kidney Disease Improving Global Outcomes (KDIGO) classification was used to diagnose and classify patients developing AKI within the first week of hospitalization. Logistic regression analysis was employed to determine factors associated with AKI development. Data were expressed as odds ratios (ORs) with 95% confidence intervals (CIs). Statistical significance was defined as a p-value < 0.05. Results: AKI occurred in 87.5% of patients with a maximum KDIGO category (19.5% with stage 1, 22.6% with stage 2 and 45.4% with stage 3). Serum lactates were higher among patients developing AKI as compared with non-AKI patients (mmol/L 29.9 ± 25.7 vs. 18.6 ± 9.3, p = 0.001; unadjusted OR 1.04 (95% CI 1.02–1.07), p = 0.001; adjusted OR 1.03 (95% CI 1.01–1.06), p = 0.024), and they were progressively higher in accordance with AKI severity (stage 1, 24.5 ± 18.7; stage 2, 25.5 ± 16.9; stage 3, 34.6 ± 30.7; p = 0.001). Conclusions: Serum lactates at ICU admission were independently associated with the occurrence of AKI in critically ill patients with sepsis