The CD6 interactome orchestrates ligand-independent T cell inhibitory signaling

Background: T-cell membrane scaffold proteins are pivotal in T cell function, acting as versatile signaling hubs. While CD6 forms a large intracellular signalosome, it is distinguished from typical scaffolds like LAT or PAG by possessing a substantial ectodomain that binds CD166, a well-characterized ligand expressed on most antigen-presenting cells (APC), through the third domain (d3) of the extracellular region. Although the intact form of CD6 is the most abundant in T cells, an isoform lacking d3 (CD6∆d3) is transiently expressed on activated T cells. Still, the precise character of the signaling transduced by CD6, whether costimulatory or inhibitory, and the influence of its ectodomain on these activities are unclear. Methods: We expressed CD6 variants with extracellular deletions or cytosolic mutations in Jurkat cells containing eGFP reporters for NF-κB and NF-AT transcription factor activation. Cell activation was assessed by eGFP flow cytometry following Jurkat cell engagement with superantigen-presenting Raji cells. Using imaging flow cytometry, we evaluated the impact of the CD6-CD166 pair on cell adhesiveness during the antigen-dependent and -independent priming of T cells. We also examined the role of extracellular or cytosolic sequences on CD6 translocation to the immunological synapse, using immunofluorescence-based imaging. Results: Our investigation dissecting the functions of the extracellular and cytosolic regions of CD6 revealed that CD6 was trafficked to the immunological synapse and exerted tonic inhibition wholly dependent on its cytosolic tail. Surprisingly, however, translocation to the synapse occurred independently of the extracellular d3 and of engagement to CD166. On the other hand, CD6 binding to CD166 significantly increased T cell:APC adhesion. However, this activity was most evident in the absence of APC priming with superantigen, and thus, in the absence of TCR engagement. Conclusions: Our study identifies CD6 as a novel ‘on/off’ scaffold-receptor capable of modulating responsiveness in two ways. Firstly, and independently of ligand binding, it establishes signaling thresholds through tonic inhibition, functioning as a membrane-bound scaffold. Secondly, CD6 has the capacity for alternative splicing-dependent variable ligand engagement, modulating its checkpoint-like activity

Gestão da água e das águas residuais para uma viticultura e enologia sustentáveis no sul de Portugal - Revisão

Assessing sustainability of the wine industry requires improved characterization of its environmental impacts, namely in terms of water use. Therefore, quantification of water inputs and wastewater (WW) outputs is needed to highlight inefficiencies in wine production and related consequences for the environment. Water use and WW generation in irrigated viticulture and oenology remains insufficiently quantified for dry Mediterranean regions (e.g. South Portugal). This paper is focused on wine production under warm and dry climate conditions in the winegrowing region of Alentejo (South Portugal). This region experiences increasingly dry conditions, while the irrigated area keeps expanding, which puts exacerbates the pressure on existing local and regional water resources. Additionally, more erratic variation in climate conditions and the tendency for increasingly extreme climate events (e.g. heat waves) pose more challenges to Alentejo’s wine sector. We conclude that quantitative information on water use and management is not always easy to obtain or access, which hinders improved strategies and/or policies for water use at farm, winery and region-level. Up-to-date statistics and robust metrics can help to better characterize water use and WW flows for Alentejo’s wine region, while optimizing management in vineyards and wineries, in companies and region-wide. The paper is focused on a “Farm-Winery" scenario, which is the most common in South Portugal's wine sectorA avaliação da sustentabilidade da indústria vitivinícola requer uma caracterização detalhada do seu impacto ambiental, nomeadamente ao nível do factor água. A quantificação detalhada dos consumos de água e das águas residuais produzidas (WW) é crucial para identificação de ineficiências na indústria da vinha e do vinho. A utilização da água e a gestão dos efluentes em viticultura regada e na adega permanecem pouco quantificados nas regiões mediterrânicas. O presente trabalho centra-se na produção de vinho em condições de clima quente e seco, tomando como exemplo a região vitivinícola do Alentejo (Sul de Portugal). A região está sujeita a situações de seca mais frequentes e severas, enquanto a área regada continua em expansão, o que pressiona os recursos hídricos locais e regionais. Além disso, as condições climáticas altamente variáveis e a maior tendência para eventos climáticos extremos (e.g. ondas de calor) colocam desafios ao setor vitivinícola no Sul de Portugal. Concluímos que a informação quantitativa relativa ao uso e gestão de água não está sempre facilmente disponível, limitando a otimização de estratégias e/ou políticas para o uso da água ao nível da vinha, da adega e da região. Dados atualizados e indicadores robustos podem ajudar a caracterizar melhor o uso de água e a geração de água residual na região vitivinícola do Alentejo, otimizando a gestão na vinha e na adega, ao nível da empresa e da região. O artigo centra-se num cenário de produtor-engarrafador (“Farm-Winery”), que é o mais comum no setor vitivinícola no Sul de Portugalinfo:eu-repo/semantics/publishedVersio

Optimal use of visual information in adolescents and young adults with developmental coordination disorder

Recent reports offer contrasting views on whether or not the use of online visual control is impaired in individuals with developmental coordination disorder (DCD). This study explored the optimal temporal basis for processing and using visual information in adolescents and young adults with DCD. Participants were 22 adolescents and young adults (12 males and 10 females; M = 19 years, SD = 3). Half had been diagnosed with DCD as children and still performed poorly on the movement assessment battery for children (DCD group; n = 11), and half reported typical development (TD group; n = 11) and were age- and gender-matched with the DCD group. We used performance on a steering task as a measure of information processing and examined the use of advance visual information. The conditions varied the duration of advance visual information: 125, 250, 500, 750, and 1,000 ms. With increased duration of advance visual information, the TD group showed a pattern of linear improvement. For the DCD group, however, the pattern was best described by a U-curve where optimal performance occurred with about 750 ms of advance information. The results suggest that the DCD group has an underlying preference for immediate online processing of visual information. The exact timing for optimal online control may depend crucially on the task, but too much advance information is detrimental to performance

The NAD+-dependent deacetylase SIRT2 attenuates oxidative stress and mitochondrial dysfunction and improves insulin sensitivity in hepatocytes

Funding Information: European Regional Development Fund (ERDF), Centro 2020 Regional Operational Programme (CENTRO-01-0145-FEDER-000012: HealthyAging2020); COMPETE 2020 - Operational Programme for Competitiveness and Internationalisation and Portuguese national funds via FCT – Fundação para a Ciência e a Tecnologia (POCI-01-0145-FEDER-007440, SFRH/BPD/109347/ 2015 to R.M.O., SFRH/BD/86655/2012 to L.N. and SFRH/BPD/ 111815/2015 to P.G.); FLAD Life Science 2020 Grant to A.C.R.; European Molecular Biology Organization (EMBO Installation Grant to T.F.O.); DFG Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB) to T.F.O.Insulin resistance is a major predictor of the development of metabolic disorders. Sirtuins (SIRTs) have emerged as potential targets that can be manipulated to counteract age-related diseases, including type 2 diabetes. SIRT2 has been recently shown to exert important metabolic effects, but whether SIRT2 regulates insulin sensitivity in hepatocytes is currently unknown. The aim of this study is to investigate this possibility and to elucidate underlying molecular mechanisms. Here, we show that SIRT2 is downregulated in insulin-resistant hepatocytes and livers, and this was accompanied by increased generation of reactive oxygen species, activation of stress-sensitive ERK1/2 kinase, and mitochondrial dysfunction. Conversely, SIRT2 overexpression in insulin-resistant hepatocytes improved insulin sensitivity, mitigated reactive oxygen species production and ameliorated mitochondrial dysfunction. Further analysis revealed a reestablishment of mitochondrial morphology, with a higher number of elongated mitochondria rather than fragmented mitochondria instigated by insulin resistance. Mechanistically, SIRT2 was able to increase fusion-related protein Mfn2 and decrease mitochondrial-associated Drp1. SIRT2 also attenuated the downregulation of TFAM, a key mtDNA-associated protein, contributing to the increase in mitochondrial mass. Importantly, we found that SIRT2 expression in PBMCs of human subjects was negatively correlated with obesity and insulin resistance. These results suggest a novel function for hepatic SIRT2 in the regulation of insulin sensitivity and raise the possibility that SIRT2 activators may offer novel opportunities for preventing or treating insulin resistance and type 2 diabetes.publishersversionpublishe

The NAD+-dependent deacetylase SIRT2 attenuates oxidative stress and mitochondrial dysfunction and improves insulin sensitivity in hepatocytes

Insulin resistance is a major predictor of the development of metabolic disorders. Sirtuins (SIRTs) have emerged as potential targets that can be manipulated to counteract age-related diseases, including type 2 diabetes. SIRT2 has been recently shown to exert important metabolic effects, but whether SIRT2 regulates insulin sensitivity in hepatocytes is currently unknown. The aim of this study is to investigate this possibility and to elucidate underlying molecular mechanisms. Here, we show that SIRT2 is downregulated in insulin-resistant hepatocytes and livers, and this was accompanied by increased generation of reactive oxygen species, activation of stress-sensitive ERK1/2 kinase, and mitochondrial dysfunction. Conversely, SIRT2 overexpression in insulin-resistant hepatocytes improved insulin sensitivity, mitigated reactive oxygen species production and ameliorated mitochondrial dysfunction. Further analysis revealed a reestablishment of mitochondrial morphology, with a higher number of elongated mitochondria rather than fragmented mitochondria instigated by insulin resistance. Mechanistically, SIRT2 was able to increase fusion-related protein Mfn2 and decrease mitochondrial-associated Drp1. SIRT2 also attenuated the downregulation of TFAM, a key mtDNA-associated protein, contributing to the increase in mitochondrial mass. Importantly, we found that SIRT2 expression in PBMCs of human subjects was negatively correlated with obesity and insulin resistance. These results suggest a novel function for hepatic SIRT2 in the regulation of insulin sensitivity and raise the possibility that SIRT2 activators may offer novel opportunities for preventing or treating insulin resistance and type 2 diabetes.European Regional Development Fund (ERDF), Centro 2020 Regional Operational Programme (CENTRO-01-0145-FEDER-000012: HealthyAging2020); COMPETE 2020 - Operational Programme for Competitiveness and Internationalisation and Portuguese national funds via FCT – Fundação para a Ciência e a Tecnologia (POCI-01-0145-FEDER-007440, SFRH/BPD/109347/2015 to R.M.O., SFRH/BD/86655/2012 to L.N. and SFRH/BPD/111815/2015 to P.G.); FLAD Life Science 2020 Grant to A.C.R.; European Molecular Biology Organization (EMBO Installation Grant to T.F.O.); DFG Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB) to T.F.O

Loss of postprandial insulin clearance control by Insulin-degrading enzyme drives dysmetabolism traits

Systemic insulin availability is determined by a balance between beta-cell secretion capacity and insulin clearance (IC). Insulin-degrading enzyme (IDE) is involved in the intracellular mechanisms underlying IC. The liver is a major player in IC control yet the role of hepatic IDE in glucose and lipid homeostasis remains unexplored. We hypothesized that IDE governs postprandial IC and hepatic IDE dysfunction amplifies dysmetabolic responses and prediabetes traits such as hepatic steatosis. In a European/Portuguese population-based cohort, IDE SNPs were strongly associated with postprandial IC in normoglycemic men but to a considerably lesser extent in women or in subjects with prediabetes. Liver-specific knockout-mice (LS-IDE KO) under normal chow diet (NCD), showed reduced postprandial IC with glucose intolerance and under high fat diet (HFD) were more susceptible to hepatic steatosis than control mice. This suggests that regulation of IC by IDE contributes to liver metabolic resilience. In agreement, LS-IDE KO hepatocytes revealed reduction of Glut2 expression levels with consequent impairment of glucose uptake and upregulation of CD36, a major hepatic free fatty acid transporter. Together these findings provide strong evidence that dysfunctional IC due to abnormal IDE regulation directly impairs postprandial hepatic glucose disposal and increases susceptibility to dysmetabolic conditions in the setting of Western diet/lifestyle.publishe

Effects of a multidisciplinar cognitive rehabilitation program for patients with mild Alzheimer's disease

OBJECTIVE: To evaluate the effects of a multidisciplinary rehabilitation program on cognition, quality of life, and neuropsychiatry symptoms in patients with mild Alzheimer's disease. METHOD: The present study was a single-blind, controlled study that was conducted at a university-based day-hospital memory facility. The study included 25 Alzheimer's patients and their caregivers and involved a 12-week stimulation and psychoeducational program. The comparison group consisted of 16 Alzheimer's patients in waiting lists for future intervention. INTERVENTION: Group sessions were provided by a multiprofessional team and included memory training, computer-assisted cognitive stimulation, expressive activities (painting, verbal expression, writing), physiotherapy, and physical training. Treatment was administered twice a week during 6.5-h gatherings. MEASUREMENTS: The assessment battery comprised the following tests: Mini-Mental State Examination, Short Cognitive Test, Quality of Life in Alzheimer's disease, Neuropsychiatric Inventory, and Geriatric Depression Scale. Test scores were evaluated at baseline and the end of the study by raters who were blinded to the group assignments. RESULTS: Measurements of global cognitive function and performance on attention tasks indicated that patients in the experimental group remained stable, whereas controls displayed mild but significant worsening. The intervention was associated with reduced depression symptoms for patients and caregivers and decreased neuropsychiatric symptoms in Alzheimer's subjects. The treatment was also beneficial for the patients' quality of life. CONCLUSION: This multimodal rehabilitation program was associated with cognitive stability and significant improvements in the quality of life for Alzheimer's patients. We also observed a significant decrease in depressive symptoms and caregiver burden. These results support the notion that structured nonpharmacological interventions can yield adjunct and clinically relevant benefits in dementia treatment

EXPRESS: Atomic Absorption Spectrometry Methods to Access the Metal Solubility of Aerosols in Artificial Lung Fluid

Recent studies to quantify the health risks that fine particulate matter with anaerodynamic lessthan 2.5 micrometers (PM2.5) poseuse in vitro approaches. One of these approaches is to incubate PM2.5in artificial lysosomal fluid for a given period at body temperature. These body fluids used have a high ionic strength and as such can be challenging samples to analyzewith atomic spectroscopy techniques. AsPM2.5isaprimary healthhazard because it is tiny enough to penetrate deep into the lungsand could, in addition, dissolve in the lung fluid it is important to quantify elements of toxic and/or carcinogenic concerns, reliably and accurately. Sophisticated instrumentation and expensive pre-treatment of challenging samples are not always available, especially in developing countries. Toevaluatethe applicability of GFAAS without Zeeman correction capability to detect trace quantities of heavy metals leached from PM2.5on to artificial lungfluid, uni-and multivariate approaches have been used for optimization purposes. The limits of quantification, LOQ,obtained by theoptimizedmethod were:2μgL-1(Cu), 3μg L-1(Cr), 1μg L-1(Mn) and 10μg L-1(Pb). The addition/recovery experiments had amean accuracy of: (Cu) 99 ± 7%; 110± 8% (Cr); 95 ± 9% (Mn) and 96 ± 11% (Pb). The average soluble fractions of PM2.5incubated in artificial lysosomal fluid (ALF)for 1 hour were:1.2 0.01ng m-3Cu, 0.40.01ng m-3Cr,0.60.01ng m-3Mnand4.8 0.03ng m-3Pb.Using historical elemental 2averagesof PM2.5 in Curitiba(Cu 3.3 ng m-3, Cr 2.1 ng m-3, Mn 6.1 ng m-3, Pb 21 ng m-3), the percentage bioaccessibility were determined to beCu 38%; Cr 20%; Mn 10%; and Pb 23%.The elemental values of the atmospheric soluble fraction of Cu, Cr and,Mn were below the inhalation risk concentrations.However, for Pb, the atmospheric soluble fraction exceeded the inhalation unit risk of 0.012 ng m-3.This robust and straightforward GF AASmethod is pivotal for low and middle-income countries were most air pollution adverse effects occur andestablished lower-costtechnologies are likelyunavailable