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1.
J Alzheimers Dis ; 97(2): 791-804, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38189752

RESUMO

BACKGROUND: With continuously aging societies, an increase in the number of people with cognitive decline is to be expected. Aside from the development of causative treatments, the successful implementation of prevention strategies is of utmost importance to reduce the high societal burden caused by neurodegenerative diseases leading to dementia among which the most common cause is Alzheimer's disease. OBJECTIVE: The aim of the Luxembourgish "programme dementia prevention (pdp)" is to prevent or at least delay dementia in an at-risk population through personalized multi-domain lifestyle interventions. The current work aims to provide a detailed overview of the methodology and presents initial results regarding the cohort characteristics and the implementation process. METHODS: In the frame of the pdp, an extensive neuropsychological evaluation and risk factor assessment are conducted for each participant. Based on the results, individualized multi-domain lifestyle interventions are suggested. RESULTS: A total number of 450 participants (Mean age = 69.5 years; SD = 10.8) have been screened at different recruitment sites throughout the country, among whom 425 participants (94.4%) met the selection criteria. CONCLUSIONS: We provide evidence supporting the feasibility of implementing a nationwide dementia prevention program and achieving successful recruitment of the target population by establishing a network of different healthcare providers.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Idoso , Luxemburgo/epidemiologia , Disfunção Cognitiva/terapia , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/prevenção & controle , Estilo de Vida , Seleção de Pacientes
2.
Pharmaceuticals (Basel) ; 16(4)2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37111331

RESUMO

Continuous evaluation of the coronavirus disease 2019 (COVID-19) vaccine effectiveness in hemodialysis (HD) patients is critical in this immunocompromised patient group with higher mortality rates due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. The response towards vaccination in HD patients has been studied weeks after their first and second SARS-CoV-2 vaccination dose administration, but no further studies have been developed in a long-term manner, especially including both the humoral and cellular immune response. Longitudinal studies that monitor the immune response to COVID-19 vaccination in individuals undergoing HD are therefore necessary to prioritize vaccination strategies and minimize the pathogenic effects of SARS-CoV-2 in this high-risk group of patients. We followed up HD patients and healthy volunteers (HV) and monitored their humoral and cellular immune response three months after the second (V2+3M) and after the third vaccination dose (V3+3M), taking into consideration previous COVID-19 infections. Our cellular immunity results show that, while HD patients and HV individuals secrete comparable levels of IFN-γ and IL-2 in ex vivo stimulated whole blood at V2+3M in both naïve and COVID-19-recovered individuals, HD patients secrete higher levels of IFN-γ and IL-2 than HV at V3+3M. This is mainly due to a decay in the cellular immune response in HV individuals after the third dose. In contrast, our humoral immunity results show similar IgG binding antibody units (BAU) between HD patients and HV individuals at V3+3M, independently of their previous infection status. Overall, our results indicate that HD patients maintain strong cellular and humoral immune responses after repeated 1273-mRNA SARS-CoV-2 vaccinations over time. The data also highlights significant differences between cellular and humoral immunity after SARS-CoV-2 vaccination, which emphasizes the importance of monitoring both arms of the immune response in the immunocompromised population.

3.
Demetra (Rio J.) ; 18: 70751, 2023. ^eilus
Artigo em Inglês, Português | LILACS | ID: biblio-1442880

RESUMO

Introdução: A indústria de alimentos e os pesquisadores têm-se dedicado a desenvolver novos produtos funcionais, com características mais naturais. Assim, estudos que identifiquem a demanda dos consumidores buscando atender seus anseios são importantes. Objetivo: Avaliar o perfil e a percepção de consumidores sobre antepastos, probióticos e a intenção de compras de um antepasto de grão de bico adicionado de bactéria probiótica. Método: A avaliação foi realizada de forma on-line, por meio de questionário contendo 33 questões respondidas por 322 participantes. Nuvens de palavras foram elaboradas com os resultados obtidos. Resultados: A maioria dos participantes reside na Região Sudeste, 72,7% são do gênero feminino, 37,3% possuem renda familiar de até três salários mínimos, 75,8% sabem o que é antepasto e mais da metade já consumiu grão de bico e conhece seus benefícios. Mais de 84,0% dos participantes sabem o que são probióticos e 90,1% já consumiram produtos probióticos de base láctea. Entretanto, 78,0% demonstraram interesse por opções de produtos probióticos de origem vegetal. Sobre as características que os participantes consideram que melhor descrevem o antepasto, as mais citadas foram: pastoso, macio, agridoce, salgado e firme. A nuvem de palavras mostrou que os respondentes associam probióticos à saúde intestinal e 36% deles estariam dispostos a comprar antepasto de grão de bico contendo probiótico se o produto estivesse disponível no mercado. Conclusão: O estudo indica que os consumidores têm interesse por grão de bico e probióticos, havendo uma demanda potencial por alimentos de origem vegetal contendo probióticos.


Introduction: The food industry and researchers have been dedicated to developing new functional products with more natural characteristics. Thus, studies that identify the demand of consumers seeking to meet their desires are important. Objective: To evaluate the profile and perception of consumers about antipasti, probiotics and purchase intention of a chickpea antipasti added with probiotic bacteria. Method: The evaluation was carried out online, through a questionnaire sent to 322 participants, containing 33 questions. Word clouds were created with the results obtained. Results: Most participants live in the Southeast region, 72.7% are female, 37.3% have a family income of up to three minimum wages, 75.8% know what antipasto is and more than half have consumed beak and knows its benefits. More than 84.0% of the participants know what probiotics are and 90.1% have already consumed dairy-based probiotic products. However, 78.0% showed interest in options for probiotic products of plant origin. About the characteristics that the participants consider that best describe the antipasto, the most cited were: Pasty, Soft, Bittersweet, Salty and Firm. The word cloud showed that respondents associate probiotics with gut health and 36% of those would be willing to buy probiotic-containing chickpea antipasto if the product were available on the market. Conclusion: The study indicates that consumers are interested in chickpeas and probiotics, with a potential demand for plant-based foods containing probiotics.


Assuntos
Humanos , Percepção , Comportamento do Consumidor , Probióticos , Cicer , Dieta Saudável
4.
EClinicalMedicine ; 50: 101529, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35795713

RESUMO

Background: The CombiVacS study was designed to assess immunogenicity and reactogenicity of the heterologous ChAdOx1-S/BNT162b2 combination, and 14-day results showed a strong immune response. The present secondary analysis addresses the evolution of humoral and cellular response up to day 180. Methods: Between April 24 and 30, 2021, 676 adults primed with ChAdOx1-S were enrolled in five hospitals in Spain, and randomised to receive BNT162b2 as second dose (interventional group [IG]) or no vaccine (control group [CG]). Individuals from CG received BNT162b2 as second dose and also on day 28, as planned based on favourable results on day 14. Humoral immunogenicity, measured by immunoassay for SARS-CoV-2 receptor binding domain (RBD), antibody functionality using pseudovirus neutralisation assays for the reference (G614), Alpha, Beta, Delta, and Omicron variants, as well as cellular immune response using interferon-γ and IL-2 immunoassays were assessed at day 28 after BNT162b2 in both groups, at day 90 (planned only in the interventional group) and at day 180 (laboratory data cut-off on Nov 19, 2021). This study was registered with EudraCT (2021-001978-37) and ClinicalTrials.gov (NCT04860739). Findings: In this secondary analysis, 664 individuals (441 from IG and 223 from CG) were included. At day 28 post vaccine, geometric mean titres (GMT) of RBD antibodies were 5616·91 BAU/mL (95% CI 5296·49-5956·71) in the IG and 7298·22 BAU/mL (6739·41-7903·37) in the CG (p < 0·0001). RBD antibodies titres decreased at day 180 (1142·0 BAU/mL [1048·69-1243·62] and 1836·4 BAU/mL [1621·62-2079·62] in the IG and CG, respectively; p < 0·0001). Neutralising antibodies also waned from day 28 to day 180 in both the IG (1429·01 [1220·37-1673·33] and 198·72 [161·54-244·47], respectively) and the CG (1503·28 [1210·71-1866·54] and 295·57 [209·84-416·33], respectively). The lowest variant-specific response was observed against Omicron-and Beta variants, with low proportion of individuals exhibiting specific neutralising antibody titres (NT50) >1:100 at day 180 (19% and 22%, respectively). Interpretation: Titres of RBD antibodies decay over time, similar to homologous regimes. Our findings suggested that delaying administration of the second dose did not have a detrimental effect after vaccination and may have improved the response obtained. Lower neutralisation was observed against Omicron and Beta variants at day 180. Funding: Funded by Instituto de Salud Carlos III (ISCIII).

5.
Nat Biotechnol ; 40(11): 1680-1689, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35697804

RESUMO

Fast, high-throughput methods for measuring the level and duration of protective immune responses to SARS-CoV-2 are needed to anticipate the risk of breakthrough infections. Here we report the development of two quantitative PCR assays for SARS-CoV-2-specific T cell activation. The assays are rapid, internally normalized and probe-based: qTACT requires RNA extraction and dqTACT avoids sample preparation steps. Both assays rely on the quantification of CXCL10 messenger RNA, a chemokine whose expression is strongly correlated with activation of antigen-specific T cells. On restimulation of whole-blood cells with SARS-CoV-2 viral antigens, viral-specific T cells secrete IFN-γ, which stimulates monocytes to produce CXCL10. CXCL10 mRNA can thus serve as a proxy to quantify cellular immunity. Our assays may allow large-scale monitoring of the magnitude and duration of functional T cell immunity to SARS-CoV-2, thus helping to prioritize revaccination strategies in vulnerable populations.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Imunidade Celular , Reação em Cadeia da Polimerase , Linfócitos T
6.
Front Immunol ; 13: 845882, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35401504

RESUMO

Long-term hemodialysis (HD) patients are considered vulnerable and at high-risk of developing severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) infection due to their immunocompromised condition. Since COVID-19 associated mortality rates are higher in HD patients, vaccination is critical to protect them. The response towards vaccination against COVID-19 in HD patients is still uncertain and, in particular the cellular immune response is not fully understood. We monitored the humoral and cellular immune responses by analysis of the serological responses and Spike-specific cellular immunity in COVID-19-recovered and naïve HD patients in a longitudinal study shortly after vaccination to determine the protective effects of 1273-mRNA vaccination against SARS-CoV-2 in these high-risk patients. In naïve HD patients, the cellular immune response measured by IL-2 and IFN-É£ secretion needed a second vaccine dose to significantly increase, with a similar pattern for the humoral response. In contrast, COVID-19 recovered HD patients developed a potent and rapid cellular and humoral immune response after the first vaccine dose. Interestingly, when comparing COVID-19 recovered healthy volunteers (HV), previously vaccinated with BNT162b2 vaccine to HD patients vaccinated with 1273-mRNA, these exhibited a more robust immune response that is maintained longitudinally. Our results indicate that HD patients develop strong cellular and humoral immune responses to 1273-mRNA vaccination and argue in favor of personalized immune monitoring studies in HD patients, especially if COVID-19 pre-exposed, to adapt COVID-19 vaccination protocols for this immunocompromised population.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Anticorpos Antivirais , Vacina BNT162 , COVID-19/prevenção & controle , Humanos , Imunidade Humoral , Estudos Longitudinais , RNA Mensageiro/genética , Diálise Renal , SARS-CoV-2 , Vacinação/métodos
7.
PLoS Comput Biol ; 18(1): e1009711, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35085230

RESUMO

Project-based learning (PBL) is a dynamic student-centred teaching method that encourages students to solve real-life problems while fostering engagement and critical thinking. Here, we report on a PBL course on metabolic network modelling that has been running for several years within the Master in Integrated Systems Biology (MISB) at the University of Luxembourg. This 2-week full-time block course comprises an introduction into the core concepts and methods of constraint-based modelling (CBM), applied to toy models and large-scale networks alongside the preparation of individual student projects in week 1 and, in week 2, the presentation and execution of these projects. We describe in detail the schedule and content of the course, exemplary student projects, and reflect on outcomes and lessons learned. PBL requires the full engagement of students and teachers and gives a rewarding teaching experience. The presented course can serve as a role model and inspiration for other similar courses.


Assuntos
Redes e Vias Metabólicas , Aprendizagem Baseada em Problemas , Biologia de Sistemas/educação , Humanos , Estudantes , Pensamento
8.
NPJ Syst Biol Appl ; 7(1): 5, 2021 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-33483512

RESUMO

Metabolic modeling enables the study of human metabolism in healthy and in diseased conditions, e.g., the prediction of new drug targets and biomarkers for metabolic diseases. To accurately describe blood and urine metabolite dynamics, the integration of multiple metabolically active tissues is necessary. We developed a dynamic multi-tissue model, which recapitulates key properties of human metabolism at the molecular and physiological level based on the integration of transcriptomics data. It enables the simulation of the dynamics of intra-cellular and extra-cellular metabolites at the genome scale. The predictive capacity of the model is shown through the accurate simulation of different healthy conditions (i.e., during fasting, while consuming meals or during exercise), and the prediction of biomarkers for a set of Inborn Errors of Metabolism with a precision of 83%. This novel approach is useful to prioritize new biomarkers for many metabolic diseases, as well as for the integration of various types of personal omics data, towards the personalized analysis of blood and urine metabolites.


Assuntos
Biologia Computacional/métodos , Metabolômica/métodos , Biologia de Sistemas/métodos , Biomarcadores/sangue , Biomarcadores/urina , Simulação por Computador , Humanos , Modelos Biológicos , Especificidade de Órgãos/genética , Especificidade de Órgãos/fisiologia
9.
Sci Rep ; 10(1): 20613, 2020 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-33244054

RESUMO

Hereditary haemochromatosis (HH) is an autosomal recessive disease, where HFE C282Y homozygosity accounts for 80-85% of clinical cases among the Caucasian population. HH is characterised by the accumulation of iron, which, if untreated, can lead to the development of liver cirrhosis and liver cancer. Since iron overload is preventable and treatable if diagnosed early, high-risk individuals can be identified through effective screening employing artificial intelligence-based approaches. However, such tools expose novel challenges associated with the handling and integration of large heterogeneous datasets. We have developed an efficient computational model to screen individuals for HH using the family study data of the Hemochromatosis and Iron Overload Screening (HEIRS) cohort. This dataset, consisting of 254 cases and 701 controls, contains variables extracted from questionnaires and laboratory blood tests. The final model was trained on an extreme gradient boosting classifier using the most relevant risk factors: HFE C282Y homozygosity, age, mean corpuscular volume, iron level, serum ferritin level, transferrin saturation, and unsaturated iron-binding capacity. Hyperparameter optimisation was carried out with multiple runs, resulting in 0.94 ± 0.02 area under the receiving operating characteristic curve (AUCROC) for tenfold stratified cross-validation, demonstrating its outperformance when compared to the iron overload screening (IRON) tool.


Assuntos
Hemocromatose/diagnóstico , Programas de Rastreamento/métodos , Adulto , Inteligência Artificial , Estudos de Coortes , Feminino , Hemocromatose/metabolismo , Proteína da Hemocromatose/metabolismo , Homozigoto , Humanos , Ferro/metabolismo , Sobrecarga de Ferro/diagnóstico , Sobrecarga de Ferro/metabolismo , Aprendizado de Máquina , Masculino , Pessoa de Meia-Idade , Adulto Jovem
10.
Diabetes ; 69(8): 1692-1707, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32381645

RESUMO

A failure in self-tolerance leads to autoimmune destruction of pancreatic ß-cells and type 1 diabetes (T1D). Low-molecular-weight dextran sulfate (DS) is a sulfated semisynthetic polysaccharide with demonstrated cytoprotective and immunomodulatory properties in vitro. However, whether DS can protect pancreatic ß-cells, reduce autoimmunity, and ameliorate T1D is unknown. In this study, we report that DS, but not dextran, protects human ß-cells against cytokine-mediated cytotoxicity in vitro. DS also protects mitochondrial function and glucose-stimulated insulin secretion and reduces chemokine expression in human islets in a proinflammatory environment. Interestingly, daily treatment with DS significantly reduces diabetes incidence in prediabetic NOD mice and, most importantly, reverses diabetes in early-onset diabetic NOD mice. DS decreases ß-cell death, enhances islet heparan sulfate (HS)/HS proteoglycan expression, and preserves ß-cell mass and plasma insulin in these mice. DS administration also increases the expression of the inhibitory costimulatory molecule programmed death-1 (PD-1) in T cells, reduces interferon-γ+CD4+ and CD8+ T cells, and enhances the number of FoxP3+ cells. Collectively, these studies demonstrate that the action of one single molecule, DS, on ß-cell protection, extracellular matrix preservation, and immunomodulation can reverse diabetes in NOD mice, highlighting its therapeutic potential for the treatment of T1D.


Assuntos
Autoimunidade/efeitos dos fármacos , Sulfato de Dextrana/uso terapêutico , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/metabolismo , Células Secretoras de Insulina/efeitos dos fármacos , Animais , Western Blotting , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Quimiocinas/metabolismo , Citometria de Fluxo , Fatores de Transcrição Forkhead/metabolismo , Glutationa/metabolismo , Dissulfeto de Glutationa/metabolismo , Proteoglicanas de Heparan Sulfato/metabolismo , Humanos , Imuno-Histoquímica , Células Secretoras de Insulina/metabolismo , Camundongos , Óxidos de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Linfócitos T/metabolismo
11.
J Clin Virol ; 121: 104200, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31707201

RESUMO

INTRODUCTION: Respiratory syncytial virus (RSV) is associated with substantial morbidity and mortality since it is a predominant viral agent causing respiratory tract infections in infants, young children and the elderly. Considering the availability of the RSV vaccines in the coming years, molecular understanding in RSV is necessary. OBJECTIVE: The objective of the present study was to describe RSV epidemiology and genotype variability in Portugal during the 2014/15-2017/18 period. MATERIAL AND METHODS: Epidemiological data and RSV-positive samples from patients with a respiratory infection were collected through the non-sentinel and sentinel influenza surveillance system (ISS). RSV detection, subtyping in A and B, and sequencing of the second hypervariable region (HVR2) of G gene were performed by molecular methods. Phylogenetic trees were generated using the Neighbor-Joining method and p-distance model on MEGA 7.0. RESULTS: RSV prevalence varied between the sentinel (2.5%, 97/3891) and the non-sentinel ISS (20.7%, 3138/16779), being higher (P < 0.0001) among children aged <5 years. Bronchiolitis (62.9%, 183/291) and influenza-like illness (24.6%, 14/57) were associated (P < 0.0001) with RSV laboratory confirmation among children aged <6 months and adults ≥65 years, respectively. The HVR2 was sequenced for 562 samples. RSV-A (46.4%, 261/562) and RSV-B (53.6%, 301/562) strains clustered mainly to ON1 (89.2%, 233/261) and BA9 (92%, 277/301) genotypes, respectively, although NA1 and BA10 were also present until 2015/2016. CONCLUSION: The sequence and phylogenetic analysis reflected the relatively high diversity of Portuguese RSV strains. BA9 and ON1 genotypes, which have been circulating in Portugal since 2010/2011 and 2011/2012 respectively, predominated during the whole study period.


Assuntos
Variação Genética , Infecções por Vírus Respiratório Sincicial/epidemiologia , Vírus Sincicial Respiratório Humano/genética , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , DNA Viral/genética , Feminino , Genótipo , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Filogenia , Portugal/epidemiologia , Prevalência , Infecções por Vírus Respiratório Sincicial/virologia , Vírus Sincicial Respiratório Humano/classificação , Infecções Respiratórias/virologia , Estações do Ano , Vigilância de Evento Sentinela , Análise de Sequência de DNA , Adulto Jovem
12.
Euro Surveill ; 24(45)2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31718741

RESUMO

BackgroundWell-established influenza surveillance systems (ISS) can be used for respiratory syncytial virus (RSV) surveillance. In Portugal, RSV cases are detected through the ISS using the European Union (EU) influenza-like illness (ILI) case definition.AimTo investigate clinical predictors for RSV infection and how three case definitions (EU ILI, a modified EU acute respiratory infection, and one respiratory symptom) performed in detecting RSV infections in Portugal.MethodsThis observational retrospective study used epidemiological and laboratory surveillance data (October 2010-May 2018). Associations between clinical characteristics and RSV detection were analysed using logistic regression. Accuracy of case definitions was assessed through sensitivity, specificity, and area under the receiver operating characteristic curve (AUC). A 0.05 significance level was accepted.ResultsThe study involved 6,523 persons, including 190 (2.9%) RSV cases. Among 183 cases with age information, RSV infection was significantly more frequent among individuals < 5 years (n = 23; 12.6%) and ≥ 65 years (n = 45; 24.6%) compared with other age groups (p < 0.0001). Cough (odds ratio (OR): 2.4; 95% confidence interval (CI): 1.2-6.5) was the best RSV-infection predictor considering all age groups, while shortness of breath was particularly associated with RSV-positivity among ≤ 14 year olds (OR: 6.7; 95% CI: 2.6-17.4 for 0-4 year olds and OR: 6.7; 95% CI: 1.5-28.8 for 5-14 year olds). Systemic symptoms were significantly associated with RSV-negative and influenza-positive cases. None of the case definitions were suitable to detect RSV infections (AUC = 0.51).ConclusionTo avoid underestimating the RSV disease burden, RSV surveillance within the Portuguese sentinel ISS would require a more sensitive case definition than ILI and, even a different case definition according to age.


Assuntos
Influenza Humana/epidemiologia , Infecções por Vírus Respiratório Sincicial/diagnóstico , Vírus Sincicial Respiratório Humano/isolamento & purificação , Infecções Respiratórias/epidemiologia , Vigilância de Evento Sentinela , Adolescente , Adulto , Distribuição por Idade , Idoso , Criança , Pré-Escolar , Tosse/etiologia , Feminino , Hospitalização , Humanos , Lactente , Recém-Nascido , Influenza Humana/diagnóstico , Masculino , Pessoa de Meia-Idade , Portugal/epidemiologia , Infecções por Vírus Respiratório Sincicial/epidemiologia , Infecções Respiratórias/diagnóstico , Estudos Retrospectivos , Sensibilidade e Especificidade , Distribuição por Sexo , Adulto Jovem
13.
Front Immunol ; 10: 374, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30894860

RESUMO

Myeloid-derived suppressor cells (MDSC) are a heterogeneous population of immature cells of myeloid origin with a specific immune inhibitory function that negatively regulates the adaptive immune response. Since MDSC participate in the promotion of tolerance in the context of organ transplantation, therapeutic strategies that regulate the induction and development of MDSC have been the center of scientist attention. Here we review literature regarding induction of MDSC with demonstrated suppressive function among different types of allografts and their mechanism of action. While manipulation of MDSC represents a potential therapeutic approach for the promotion of donor specific tolerance in solid organ transplantation, further characterization of their specific phenotype, which distinguishes MDSC from non-suppressive myeloid cells, and detailed evaluation of the inhibitory mechanism that determines their suppressive function, is necessary for the realistic application of MDSC as biomarkers in health and disease and their potential use as immune cell therapy in organ transplantation.


Assuntos
Células Supressoras Mieloides/imunologia , Transplante de Órgãos , Tolerância ao Transplante , Aloenxertos , Animais , Humanos , Células Supressoras Mieloides/patologia
14.
Am J Transplant ; 19(3): 633-645, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30106232

RESUMO

Costimulatory blockade-induced murine cardiac allograft survival requires intragraft accumulation of CD11b+ Ly6Clo Ly6G- regulatory myeloid cells (Mregs) that expand regulatory T cells (Tregs) and suppress effector T cells (Teffs). We previously showed that C5a receptor (C5aR1) signaling on T cells activates Teffs and inhibits Tregs, but whether and/or how C5aR1 affects Mregs required for transplant survival is unknown. Although BALB/c hearts survived >60 days in anti-CD154 (MR1)-treated or cytotoxic T-lymphocyte associated protein 4 (CTLA4)-Ig-treated wild-type (WT) recipients, they were rejected at ~30 days in MR1-treated or CTLA4-Ig-treated recipients selectively deficient in C5aR1 restricted to myeloid cells (C5ar1fl/fl xLysM-Cre). This accelerated rejection was associated with ~2-fold more donor-reactive T cells and ~40% less expansion of donor-reactive Tregs. Analysis of graft-infiltrating mononuclear cells on posttransplant day 6 revealed fewer Ly6Clo monocytes in C5ar1fl/fl xLysM-Cre recipients. Expression profiling of intragraft Ly6Clo monocytes showed that C5aR1 deficiency downregulated genes related to migration/locomotion without changes in genes associated with suppressive function. Cotransfer of C5ar1fl/fl and C5ar1fl/fl xLysM-Cre myeloid cells into MR1-treated allograft recipients resulted in less accumulation of C5ar1-/- cells within the allografts, and in vitro assays confirmed that Ly6Chi myeloid cells migrate to C5a/C5aR1-initiated signals. Together, our results newly link myeloid cell-expressed C5aR1 to intragraft accumulation of myeloid cells required for prolongation of heart transplant survival induced by costimulatory blockade.


Assuntos
Abatacepte/imunologia , Antígeno CTLA-4/imunologia , Movimento Celular , Sobrevivência de Enxerto , Transplante de Coração/métodos , Células Supressoras Mieloides/imunologia , Receptor da Anafilatoxina C5a/metabolismo , Abatacepte/química , Abatacepte/metabolismo , Aloenxertos , Animais , Antígeno CTLA-4/metabolismo , Rejeição de Enxerto , Cardiopatias/imunologia , Cardiopatias/terapia , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe I/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Antígenos de Histocompatibilidade Menor/imunologia , Antígenos de Histocompatibilidade Menor/metabolismo , Células Supressoras Mieloides/metabolismo , Células Supressoras Mieloides/patologia , Receptor da Anafilatoxina C5a/genética , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Linfócitos T Reguladores/patologia
15.
Cancer Immunol Immunother ; 68(4): 661-672, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30357490

RESUMO

Myeloid cells play a pivotal role in regulating innate and adaptive immune responses. In inflammation, autoimmunity, and after transplantation, myeloid cells have contrasting roles: on the one hand they initiate the immune response, promoting activation and expansion of effector T-cells, and on the other, they counter-regulate inflammation, maintain tissue homeostasis, and promote tolerance. The latter activities are mediated by several myeloid cells including polymorphonuclear neutrophils, macrophages, myeloid-derived suppressor cells, and dendritic cells. Since these cells have been associated with immune suppression and tolerance, they will be further referred to as myeloid regulatory cells (MRCs). In recent years, MRCs have emerged as a therapeutic target or have been regarded as a potential cellular therapeutic product for tolerance induction. However, several open questions must be addressed to enable the therapeutic application of MRCs including: how do they function at the site of inflammation, how to best target these cells to modulate their activities, and how to isolate or to generate pure populations for adoptive cell therapies. In this review, we will give an overview of the current knowledge on MRCs in inflammation, autoimmunity, and transplantation. We will discuss current strategies to target MRCs and to exploit their tolerogenic potential as a cell-based therapy.


Assuntos
Autoimunidade , Homeostase , Tolerância Imunológica , Inflamação/etiologia , Inflamação/metabolismo , Células Mieloides/imunologia , Células Mieloides/metabolismo , Animais , Biomarcadores , Suscetibilidade a Doenças , Humanos , Imunomodulação , Imunofenotipagem , Macrófagos/imunologia , Macrófagos/metabolismo , Monócitos/imunologia , Monócitos/metabolismo , Neutrófilos/imunologia , Neutrófilos/metabolismo , Transplante de Órgãos , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Transplante Homólogo
16.
Immunity ; 49(5): 819-828.e6, 2018 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-30413362

RESUMO

Inducing graft acceptance without chronic immunosuppression remains an elusive goal in organ transplantation. Using an experimental transplantation mouse model, we demonstrate that local macrophage activation through dectin-1 and toll-like receptor 4 (TLR4) drives trained immunity-associated cytokine production during allograft rejection. We conducted nanoimmunotherapeutic studies and found that a short-term mTOR-specific high-density lipoprotein (HDL) nanobiologic treatment (mTORi-HDL) averted macrophage aerobic glycolysis and the epigenetic modifications underlying inflammatory cytokine production. The resulting regulatory macrophages prevented alloreactive CD8+ T cell-mediated immunity and promoted tolerogenic CD4+ regulatory T (Treg) cell expansion. To enhance therapeutic efficacy, we complemented the mTORi-HDL treatment with a CD40-TRAF6-specific nanobiologic (TRAF6i-HDL) that inhibits co-stimulation. This synergistic nanoimmunotherapy resulted in indefinite allograft survival. Together, we show that HDL-based nanoimmunotherapy can be employed to control macrophage function in vivo. Our strategy, focused on preventing inflammatory innate immune responses, provides a framework for developing targeted therapies that promote immunological tolerance.


Assuntos
Sobrevivência de Enxerto/imunologia , Terapia de Imunossupressão , Inflamação/imunologia , Células Mieloides/imunologia , Células Mieloides/metabolismo , Transplante de Órgãos , Aloenxertos , Animais , Biomarcadores , Proteína HMGB1/genética , Tolerância Imunológica , Imunidade Inata , Memória Imunológica , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Serina-Treonina Quinases TOR/metabolismo , Vimentina/genética
17.
Hig. aliment ; 32(280/281): 92-97, 30/06/2018. tab
Artigo em Português | LILACS | ID: biblio-910585

RESUMO

Objetivou-se elaborar e caracterizar leites fermentados sabor coco, maracujá e juçara, acrescidos ou não de polpa de yacon e verificar a viabilidade de Lactobacillus acidiphilus LA-5 nos produtos. Ao leite adicionou-se soro, sacarose e estabilizante, sendo a mistura pasteurizada, resfriada, adicionada da bactéria probiótica e fermentada até acidez de 0,65%. Utilizou-se separadamente 4% das polpas de coco, maracujá e juçara nos produtos, sendo estes fracionados em dois recipientes. A um deles foi adicionado 4% de polpa de yacon e ao outro não. Realizou-se a caracterização físico-química, microbiológica e sensorial nos tempos 0, 15 e 30 dias. O pH variou de 3,64 a 4,09 e a acidez entre 0,74% e 0,99%, sendo estes influenciados pelo tempo e pela polpa utilizada. Constatou-se <3,0 NMP/g de coliformes a 30 °C e a 45 °C e a contagem de fungos filamentosos e leveduras também atendeu à legislação. A menor contagem de L. acidiphilus LA-5 foi 7,37 log UFC/g nas amostras sabor maracujá após 30 dias. O produto sabor juçara apresentou maiores contagens dessa bactéria. Não foi constatada influência da polpa de yacon na contagem da cultura probiótica (p>0,05) e não houve diferença (p>0,05) do leite fermentado dos sabores coco e juçara fabricados com e sem yacon para os atributos sensoriais. Entretanto, o leite fermentado sabor maracujá fabricado com e sem yacon diferiram (p<0,05). É, portanto, viável o desenvolvimento dos leites fermentados potencialmente funcionais propostos.


The aim of this work was to elaborate and characterize coconut, passion fruit and juçara flavored fermented milks, with or without yacon pulp and to verify the viability of Lactobacillus acidiphilus LA-5 in the products. Whey, sucrose and stabilizer were added to the milk and the mixture pasteurized, cooled, added to the probiotic bacterium and fermented to acidity of 0.65%. Four percent of coconut, passion fruit and juçara pulp was separately used in the products, which were divided into two containers. To one of them was added 4% of yacon pulp and the other not. Physico-chemical, microbiological and sensorial characterization were performed at 0, 15 and 30 days. The pH varied from 3.64 to 4.09 and the acidity ranged from 0.74% to 0.99%, influenced by the time and the pulp used. <3.0 NMP/g of coliforms were observed at 30 °C and 45 °C and the count of filamentous fungi and yeast also complied with the legislation. The lowest L. acidiphilus LA-5 count was 7.37 log CFU/g in passion fruit taste samples after 30 days. The product juçara flavor had higher counts of this bacterium. No influence of the yacon pulp was observed on the probiotic culture count (p>0.05) and there was no difference (p>0.05) in the fermented milk of the coconut and juçara flavors made with and without yacon for the sensory attributes. However, fermented milk flavored passion fruit made with and without yacon differed (p<0.05). Therefore, the development of proposed potentially functional fermented milks is feasible.


Assuntos
Probióticos , Produtos Fermentados do Leite , Lactobacillus acidophilus , Indústria Alimentícia , Alimentos Integrais , Indústria de Laticínios , Frutas
18.
Rev. bras. anestesiol ; 68(3): 238-243, May-June 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-958290

RESUMO

Abstract Background and objectives: Major burn surgery causes large hemorrhage and coagulation dysfunction. Treatment algorithms guided by ROTEM® and factor VIIa reduce the need for blood products, but there is no evidence regarding factor XIII. Factor XIII deficiency changes clot stability and decreases wound healing. This study evaluates the efficacy and safety of factor XIII correction and its repercussion on transfusion requirements in burn surgery. Methods: Randomized retrospective study with 40 patients undergoing surgery at the Burn Unit, allocated into Group A those with factor XIII assessment (n = 20), and Group B, those without assessment (n = 20). Erythrocyte transfusion was guided by a hemoglobin trigger of 10 g.dL-1 and the other blood products by routine coagulation and ROTEM® tests. Analysis of blood product consumption included units of erythrocytes, fresh frozen plasma, platelets, and fibrinogen. The coagulation biomarker analysis compared the pre- and post-operative values. Results and conclusions: Group A (with factor XIII study) and Group B had identical total body surface area burned. All patients in Group A had a preoperative factor XIII deficiency, whose correction significantly reduced units of erythrocyte concentrate transfusion (1.95 vs. 4.05, p = 0.001). Pre- and post-operative coagulation biomarkers were similar between groups, revealing that routine coagulation tests did not identify factor XIII deficiency. There were no recorded thromboembolic events. Correction of factor XIII deficiency in burn surgery proved to be safe and effective for reducing perioperative transfusion of erythrocyte units.


Resumo Justificativa e objetivos: A cirurgia no grande queimado causa hemorragia de grande porte e disfunção da coagulação. Os algoritmos de tratamento guiados por ROTEM® e fator VIIa reduzem as necessidades de hemoderivados, mas falta evidência em relação ao fator XIII. A deficiência do fator XIII altera a estabilidade do coágulo e diminui a cicatrização. Este estudo avalia a eficácia e a segurança da correção do fator XIII e sua repercussão nas necessidades transfusionais na cirurgia do queimado. Métodos: Estudo retrospectivo randomizado de 40 doentes submetidos à cirurgia na Unidade de Queimados alocados em grupo A com estudo do fator XIII (n = 20) e grupo B sem estudo (n = 20). A transfusão eritrocitária foi guiada por gatilho de hemoglobina de 10 g.dL-1 e os outros hemoderivados por testes de coagulação de rotina e ROTEM®. A análise do consumo de hemoderivados incluiu unidades de eritrócitos, plasma fresco congelado, plaquetas e fibrinogênio. A análise dos biomarcadores da coagulação comparou os valores pré e pós-operatórios. Resultados e conclusões: O grupo A (com estudo de fator XIII) e o grupo B apresentaram área de superfície corporal total queimada idêntica. Todos os doentes do grupo A revelaram déficit pré-operatório de fator XIII, cuja correção reduziu significativamente a transfusão de unidades de concentrado eritrocitário (1,95 vs. 4,05, p = 0,001). Os biomarcadores de coagulação pré e pós-operatórios foram semelhantes entre os grupos, revelaram que os testes de coagulação de rotina não identificam o déficit de fator XIII. Sem eventos tromboembólicos registrados. A correção do fator XIII na cirurgia do queimado revelou-se segura e eficaz na redução da transfusão perioperatória de unidades de eritrócitos.


Assuntos
Humanos , Procedimentos Cirúrgicos Operatórios , Coagulação Sanguínea , Queimaduras/sangue , Fator XII , Cuidados Críticos/métodos , Hemostasia , Estudos Retrospectivos
19.
Hig. aliment ; 32(276/277): 108-112, fev. 27, 2018.
Artigo em Português | LILACS | ID: biblio-884014

RESUMO

[{"text": "Este trabalho objetivou avaliar a\r\ninfluência da cloração da água utilizada\r\nna higienização de tanques de\r\nexpansão na contagem de Escherichia\r\ncoli e Pseudomonas sp. do leite\r\ncru refrigerado. Amostras de leite cru\r\ne de água de18 tanques de expansão\r\nforam avaliadas por um ano, sendo\r\nque em 9 tanques não havia sistema\r\nde cloração da água implantado no\r\ndecorrer de 12 meses e nos outros\r\n9, por 6 meses não houve cloração\r\nda água e nos 6 meses seguintes o\r\nsistema foi implantado. Para determinação\r\nde E. coli no leite cru e na\r\nágua utilizou-se a técnica do Número\r\nMais Provável (NMP) e para\r\na contagem de Pseudomonas sp.\r\nutilizou-se Ágar Para Isolamento de\r\nPseudomonas (PIA). Constataram-\r\n-se valores médios de 1,5NMP/mL e\r\n1,6NMP/mLde E. coli no leite e na\r\nágua, respectivamente, nas amostras\r\nprovenientes dos 9 tanques em que a\r\nágua utilizada não foiclorada por 12\r\nmeses. As amostras de leite e água\r\nprocedentes dos 9 tanques que receberam\r\nágua clorada durante a limpeza\r\npor 6 meses apresentaram em média\r\n1,8NMP/mL e < 1,1 NMP/mL de\r\nE.coli, respectivamente. A contagem\r\nmédia de Pseudomonas sp. nas amostras\r\nde água procedentes dos 9 tanques\r\nem que a água utilizada no processo\r\nde limpeza não recebeu cloração por\r\n6 meses e que posteriormente passou\r\na ser clorada foi 1,1x103UFC/mL e\r\n1,2x102UFC/mL, respectivamente.\r\nPor outro lado,amédia das contagens\r\nde Pseudomonas sp. foi de 9,8x104\r\nUFC/mL e 5,1x105 UFC/mL nas\r\namostras de leite procedentes dos tanques\r\nem que a água utilizada no processo\r\nde limpeza não recebeu cloração\r\npor 6 meses e que posteriormente\r\npassou a ser clorada, respectivamente,\r\no que indica que esta bactéria acessa o\r\nleite cru a partir de diferentes fontes\r\nde contaminação, além da água. Assim,\r\na cloração foi eficiente apenas\r\nna redução da contagem de E. coli e\r\nPseudomonas sp. na água.(AU)", "_i": "pt"}]


Assuntos
Humanos , Amostras de Água , Cloro/análise , Desinfecção da Água/métodos , Leite/microbiologia , Armazenamento de Alimentos , Pseudomonas/isolamento & purificação , Indústria de Laticínios , Escherichia coli/isolamento & purificação , Controle da Contaminação da Água
20.
Am J Transplant ; 18(5): 1247-1255, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29314558

RESUMO

The colony-stimulating factor 1 (CSF1) regulates the differentiation and function of tissue macrophages and determines the outcome of the immune response. The molecular mechanisms behind CSF1-mediated macrophage development remain to be elucidated. Here we demonstrate that neutrophil-derived CSF1 controls macrophage polarization and proliferation, which is necessary for the induction of tolerance. Inhibiting neutrophil production of CSF1 or preventing macrophage proliferation, using targeted nanoparticles loaded with the cell cycle inhibitor simvastatin, abrogates the induction of tolerance. These results provide new mechanistic insights into the developmental requirements of tolerogenic macrophages and identify CSF1 producing neutrophils as critical regulators of the immunological response.


Assuntos
Transplante de Coração , Tolerância Imunológica/imunologia , Fator Estimulador de Colônias de Macrófagos/metabolismo , Macrófagos/imunologia , Neutrófilos/imunologia , Tolerância ao Transplante/imunologia , Animais , Diferenciação Celular , Proliferação de Células , Feminino , Humanos , Macrófagos/citologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Neutrófilos/metabolismo , Transdução de Sinais
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