Mannosylated glycans impair normal T-cell development by reprogramming commitment and repertoire diversity

T-cell development ensures the formation of diverse repertoires of T-cell receptors (TCRs) that recognize a variety of antigens. Glycosylation is a major posttranslational modification present in virtually all cells, including T-lymphocytes, that regulates activity/functions. Although these structures are known to be involved in TCR-selection in DP thymocytes, it is unclear how glycans regulate other thymic development processes and how they influence susceptibility to disease. Here, we discovered stage-specific glycome compositions during T-cell development in human and murine thymocytes, as well as dynamic alterations. After restricting the N-glycosylation profile of thymocytes to high-mannose structures, using specific glycoengineered mice (Rag1CreMgat1fl/fl), we showed remarkable defects in key developmental checkpoints, including ß-selection, regulatory T-cell generation and γδT-cell development, associated with increased susceptibility to colon and kidney inflammation and infection. We further demonstrated that a single N-glycan antenna (modeled in Rag1CreMgat2fl/fl mice) is the sine-qua-non condition to ensure normal development. In conclusion, we revealed that mannosylated thymocytes lead to a dysregulation in T-cell development that is associated with inflammation susceptibility.Funded by the “2022 Lupus Research Alliance (LRA) Lupus Innovation Award”. Institutional funding from the Portuguese Foundation for Science and Technology (FCT): projects NORTE-01-0145-FEDER-000029, POCI-01/0145-FEDER-016601, POCI-01-0145-FEDER-028772, and PTDC/MEC-REU/28772/2017 (SSP). This study was co-funded by the European Union (ERC Synergy, GlycanSwitch, 101071386). Views and opinions expressed are, however, those of the author(s) only and do not necessarily reflect those of the European Union or the European Research Council Executive Agency. The study was also co-funded by the European Union, GlycanTrigger project, Grant Agreement No: 101093997. Views and opinions expressed are, however, those of the author(s) only and do not necessarily reflect those of the European Union or European Health and Digital Executive Agency. Neither the European Union nor the granting authority can be held responsible for them. A grant was received from the Portuguese group of study in autoimmune diseases (NEDAI) to SSP. MMV (PD/BD/135452/2017; COVID/BD/152488/2022) received funding from the FCT

The institutions of archaic post-modernity and their organizational and managerial consequences: The case of Portugal

The long march of modernization of the Western societies tends to be presented as following a regular sequence: societies and institutions were pre-modern, and then they were modernized, eventually becoming post-modern. Such teleology may provide an incomplete or distorted narrative of societal evolution in many parts of the world, even in the ‘post-modern heartland’ of Western Europe, with Portugal being a case in point. The concept of archaic post-modernity has been developed by a philosopher, José Gil, to show how Portuguese institutions and organizations combine elements of pre-modernity and post-modernity. The notion of an archaic post-modernity is advanced in order to provide an alternative account of the modernization process, which enriches discussion of the varieties of capitalism. Differences in historical experiences create singularities that may be considered in the analysis of culture, management and organization

A Brazilian original pedagogical approach to the teaching of neurology

The two-arm Clinical Decisions/Diagnostic Workshop (CD/DW) approach to undergraduate medical education has been successfully used in Brazil. Objective Present the CD/DW approach to the teaching of stroke, with the results of its pre-experimental application and of a comparative study with the traditional lecture-case discussion approach. Method Application of two questionnaires (opinion and Knowledge-Attitudes-Perceptions-KAP) to investigate the non-inferiority of the CD/DW approach. Results The method was well accepted by teachers and students alike, the main drawback being the necessarily long time for its completion by the students, a feature that may better cater for different educational needs. The comparative test showed the CD/DW approach to lead to slightly higher cognitive acquisition as opposed to the traditional method, clearly showing its non-inferiority status. Conclusion The CD/DW approach seems to be another option for teaching neurology in undergraduate medical education, with the bonus of respecting each learner`s time

Evaluation of in vitro toxicity of N,N-dimethyl-2-propen-1-amines isomers

The trypanocidal activities of cis-3-(4'-bromo[1,1'-biphenyl]-4-yl)-3-(phenyl)-N,N-dimethyl-2-propen-1-amine (Vb) and cis-3-(4'-bromo[1,1'-biphenyl]-4-yl)-3-(4-bromophenyl)-N,N-dimethyl-2-propen-1-anine (Vg) appeared 6.3 and 3.5 fold more active than the trans-isomers, respectively Multi-endpoints for toxicity were also applied. Neutral red uptake (NRU), tetrazolium salt reduction (MTT), DNA content on V79 fibroblast cell culture and acute toxicity von E. coli were measured. The IC50 through DNA contents was lower for the cis-isomers in both series of compounds 5b: 7.8 mu M and 5g: 5.2 mu M). NRU values for derivative 5b in isomeric mixture shows the same value as the isolated isomers however, in the case of 5g a more significant toxicity of the cis-isomer was found. MTT values show that 5g is more toxic than 5b. In both cases, the acute toxicity of the trans-isomers was higher than that of the cis-isomers.541184785

Application of a multi-endpoint cytotoxicity assay to the trypanocidal compounds 2-propen-1-amine derivatives and determination of their acute toxicity

A multi-endpoint cytotoxicity method using the V79 fibroblast cell line was applied to 2-propen-1-amine derivatives and Nifurtimox that presented trypanocidal activity. The acute toxicity of the compounds was also studied using E. coli. The 2-propen-1-amine derivatives (X = p-H; p-Br; p-CH3SO2; p-NO2) exhibited higher trypanocidal activity (ID50) (trypomastigotes) 12.1-35.0 mu M) than Nifurtimox (157.0 mu M). For the cytotoxicity assessment, three independent endpoints, namely DNA content, neutral red uptake, and MTT, were used. Nifurtimox exhibited a lower toxicity (250-500 mu M) than the 2-propen-1-amine derivatives (4.9-48.0 mu M) and the 2-propen-1-amine derivatives exhibited lower EC50 values (5.7-24.0 mu M) than Nifurtimox (35.0 mu M), except for the p-CH3SO2 group whose IC50 was 110.0 mu M. Although Nifurtimox is a recognized toxic compound that needs metabolization to express its toxicity, its toxicity was lower than that of 2-propen-1-amines in all tests, Thus, we conclude that the multi-endpoint method for cytotoxicity evaluation using the V-79 fibroblast cell line is not adequate for compounds that need metabolization. This study led us to select the p-bromo 2-propen-1-amine derivative as one of the less toxic and more active trypanocide derivatives for further in vivo studies.11215316

Acute coronary syndromes in anaemic patients: the bad or the ugly?

Abstract Funding Acknowledgements Type of funding sources: None. Background Patients with anaemia are at increased risk of composite cardiovascular (CV) events and all-cause mortality. However, anaemia poses a challenge to doctors when in the context of an acute coronary syndrome (ACS) and the urge to offer intervention treatment and therefore antiplatelet therapy. Purpose To study the prognostic impact of anaemia in a population with ACS. Methods 436 ACS patients admitted to a single coronary care with anaemia (male gender, haemoglobin [Hb] &amp;lt;13 g/dL; female gender, Hb &amp;lt; 12 g/dL) who were discharged from hospital were included. The primary endpoint was long-term all-cause mortality. Cox regression was conducted to evaluate the impact on the primary endpoint. The median of follow-up was 36 (± 31) months. Results Sixty-four percent of the patients were male, with a mean age 75 ± 10 years old. The majority (47%) was admitted with non-ST elevation myocardial infarction. Most of them had previous history of hypertension (87%), dyslipidaemia (63%) and chronic kidney disease (58%), while a minority had a diagnosis of diabetes mellitus (46%). Most of the patients remained in Killip-Kimbal class I throughout hospital-stay. Coronary angiography was not conducted in 15% of the patients. Thirty-six percent of the patients were conservatively treated (not submitted to percutaneous coronary intervention or coronary artery bypass graft). At discharge, 1% of the patients had no antiplatelet or anticoagulation therapy prescribed; 7% had simple antiplatelet therapy; 1% only had anticoagulation therapy; 67% had double antiplatelet therapy; 1% had double therapy (anticoagulation plus a single antiplatelet agent) and 5% had triple therapy (anticoagulation plus two antiplatelets agents); missing data about therapy at discharge in 18% of the patients. 224 patients met the primary outcome. In univariate analysis, nor antiplatelet neither anticoagulation strategies were related to the outcome (P = 0.59; P = 0.73, respectively). In a multivariable model adjusted for age, Hb level, glomerular filtration rate, heart failure diagnosis, left ventricular function (3 categories), maximum troponin I and treatment option (conservative vs revascularization), Hb level remains an important prognosis predictor (HR 0.86, 95% CI 0.77-0.97, per each g/dL increase). In this model, besides from Hb level, only age (HR 1.04, 95% CI 1.02-1.05) and moderate to severely impaired LV function (HR 1.91, 95% CI 1.38-2.63) remained associated with the outcome. Conclusion The outcome attributed to anaemia patients seems to be independent of treatment strategies and it is related to the Hb level itself. This reinforces the need to explore reversible causes of anaemia, as small increases in Hb level may have a major impact on the prognosis of these patients. </jats:sec