865 research outputs found

    Blockade of MIF-CD74 Signalling on Macrophages and Dendritic Cells Restores the Antitumour Immune Response Against Metastatic Melanoma

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    Mounting an effective immune response against cancer requires the activation of innate and adaptive immune cells. Metastatic melanoma is the most aggressive form of skin cancer. While immunotherapies have shown a remarkable success in melanoma treatment, patients develop resistance by mechanisms that include the establishment of an immune suppressive tumor microenvironment. Thus, understanding how metastatic melanoma cells suppress the immune system is vital to develop effective immunotherapies against this disease. In this study, we find that macrophages (MOs) and dendritic cells (DCs) are suppressed in metastatic melanoma and that the Ig-CDR-based peptide C36L1 is able to restore MOs and DCs' antitumorigenic and immunogenic functions and to inhibit metastatic growth in lungs. Specifically, C36L1 treatment is able to repolarize M2-like immunosuppressive MOs into M1-like antitumorigenic MOs, and increase the number of immunogenic DCs, and activated cytotoxic T cells, while reducing the number of regulatory T cells and monocytic myeloid-derived suppressor cells in metastatic lungs. Mechanistically, we find that C36L1 directly binds to the MIF receptor CD74 which is expressed on MOs and DCs, disturbing CD74 structural dynamics and inhibiting MIF signaling on these cells. Interfering with MIF-CD74 signaling on MOs and DCs leads to a decrease in the expression of immunosuppressive factors from MOs and an increase in the capacity of DCs to activate cytotoxic T cells. Our findings suggest that interfering with MIF-CD74 immunosuppressive signaling in MOs and DCs, using peptide-based immunotherapy can restore the antitumor immune response in metastatic melanoma. Our study provides the rationale for further development of peptide-based therapies to restore the antitumor immune response in metastatic melanoma

    Documento de consenso sobre codificação de exames de ressonância magnética cardíaca em Portugal

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    One of the obstacles to more frequent and appropriate use of cardiac magnetic resonance (CMR) in Portugal has been the lack of specific codes that accurately describe these examinations as they are currently performed. In this consensus document, recommendations are made for updating and standardizing CMR codes in Portugal. Guidance on which techniques and codes should be used in the most common clinical scenarios is also provided

    Assessing early memories of threat and subordination: Confirmatory factor analyisis of the early life experiences scale for adolescents.

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    The Early Life Experiences Scale (ELES) is a self-report questionnaire that assesses personal feelings of perceived threat and submissiveness in interactions within family. This paper presents the adaptation and validation of the ELES in Portuguese language for adolescents. The sample was composed of 771 adolescents from community schools with ages between 13 and 18 years old. Along with ELES, participants also answered the Early Memories of Warmth and Safeness Scale and the Positive and Negative Affect Schedule for Children and Adolescents. Confirmatory factor analysis (CFA) was performed to test the factor structure of the ELES and results confirm a three-factor structure, composed by Threat, Submissiveness and Unvalued dimensions. These emotional memories focused on perceived threat, submissiveness and unvalued seem to have a distinct nature. The scale also showed adequate internal consistency, good test-retest reliability and convergent validity with measures of positive emotional memories, positive and negative affect. There were sex differences for threat subscale and age differences for submissiveness subscale. Overall, these findings suggest that the ELES in its Portuguese version for adolescents may be a useful tool for research, educational and clinical contexts with school-aged adolescents

    Genomic Expression Analysis Reveals Strategies of Burkholderia cenocepacia to Adapt to Cystic Fibrosis Patients' Airways and Antimicrobial Therapy

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    Pulmonary colonization of cystic fibrosis (CF) patients with Burkholderia cenocepacia or other bacteria of the Burkholderia cepacia complex (Bcc) is associated with worse prognosis and increased risk of death. During colonization, the bacteria may evolve under the stressing selection pressures exerted in the CF lung, in particular, those resulting from challenges of the host immune defenses, antimicrobial therapy, nutrient availability and oxygen limitation. Understanding the adaptive mechanisms that promote successful colonization and long-term survival of B. cenocepacia in the CF lung is essential for an improved therapeutic outcome of chronic infections. To get mechanistic insights into these adaptive strategies a transcriptomic analysis, based on DNA microarrays, was explored in this study. The genomic expression levels in two clonal variants isolated during long-term colonization of a CF patient who died from the cepacia syndrome were compared. One of the isolates examined, IST439, is the first B. cenocepacia isolate retrieved from the patient and the other isolate, IST4113, was obtained three years later and is more resistant to different classes of antimicrobials. Approximately 1000 genes were found to be differently expressed in the two clonal variants reflecting a marked reprogramming of genomic expression. The up-regulated genes in IST4113 include those involved in translation, iron uptake (in particular, in ornibactin biosynthesis), efflux of drugs and in adhesion to epithelial lung tissue and to mucin. Alterations related with adaptation to the nutritional environment of the CF lung and to an oxygen-limited environment are also suggested to be a key feature of transcriptional reprogramming occurring during long-term colonization, antibiotic therapy and the progression of the disease

    Is the functional interaction between adenosine A2A receptors and metabotropic glutamate 5 receptors a general mechanism in the brain? Differences and similarities between the striatum and the hippocampus

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    The aim of the present paper was to examine, in a comparative way, the occurrence and the mechanisms of the interactions between adenosine A2A receptors (A2ARs) and metabotropic glutamate 5 receptors (mGlu5Rs) in the hippocampus and the striatum. In rat hippocampal and corticostriatal slices, combined ineffective doses of the mGlu5R agonist 2-chloro-5-hydroxyphenylglycine (CHPG) and the A2AR agonist CGS 21680 synergistically reduced the slope of excitatory postsynaptic field potentials (fEPSPs) recorded in CA1 and the amplitude of field potentials (FPs) recorded in the dorsomedial striatum. The cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA) pathway appeared to be involved in the effects of CGS 21680 in corticostriatal but not in hippocampal slices. In both areas, a postsynaptic locus of interaction appeared more likely. N-methyl-D-aspartate (NMDA) reduced the fEPSP slope and FP amplitude in hippocampal and corticostriatal slices, respectively. Such an effect was significantly potentiated by CHPG in both areas. Interestingly, the A2AR antagonist ZM 241385 significantly reduced the NMDA-potentiating effect of CHPG. In primary cultures of rat hippocampal and striatal neurons (ED 17, DIV 14), CHPG significantly potentiated NMDA-induced lactate dehydrogenase (LDH) release. Again, such an effect was prevented by ZM 241385. Our results show that A2A and mGlu5 receptors functionally interact both in the hippocampus and in the striatum, even though different mechanisms seem to be involved in the two areas. The ability of A2ARs to control mGlu5R-dependent effects may thus be a general feature of A2ARs in different brain regions (irrespective of their density) and may represent an additional target for the development of therapeutic strategies against neurological disorders

    Validation of persuasive messages for the promotion of physical activity among people with coronary heart disease

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    OBJECTIVE: to validate the content of persuasive messages for promoting walking among patients with coronary heart disease (CHD). The messages were constructed to strengthen or change patients' attitudes to walking. METHOD: the selection of persuasive arguments was based on behavioral beliefs (determinants of attitude) related to walking. The messages were constructed based in the Elaboration Likelihood Model and were submitted to content validation. RESULTS: the data was analyzed with the content validity index and by the importance which the patients attributed to the messages' persuasive arguments. Positive behavioral beliefs (i.e. positive and negative reinforcement) and self-efficacy were the appeals which the patients considered important. The messages with validation evidence will be tested in an intervention study for the promotion of the practice of physical activity among patients with CHD.OBJETIVO: validar el contenido de mensajes persuasivos para promover la caminata entre pacientes con enfermedad arterial coronaria (DAC). Los mensajes fueron construidos objetivando al fortalecimiento/cambio de la actitud del paciente con relación a la caminata. MÉTODO: la selección de los argumentos persuasivos fue basada en las creencias comportamentales (determinantes de la actitud) relacionadas a la caminata. Los mensajes fueron construidos con base en el Modelo de Probabilidad de Elaboración y sometidos a la validez de contenido. RESULTADOS: los datos fueron analizados por medio del índice de validez de contenido y por la importancia atribuida por los pacientes a los argumentos persuasivos de los mensajes. Las creencias comportamentales positivas (ejemplo: refuerzo positivo y negativo) y la autoeficacia fueron los reclamos considerados importantes por los pacientes. Los mensajes con evidencias de validación serán testadas en estudio de intervención para promoción de la práctica de actividad física entre pacientes con DAC.OBJETIVO: validar o conteúdo de mensagens persuasivas para promover a caminhada entre pacientes com doença arterial coronária (DAC). As mensagens foram construídas com vistas ao fortalecimento/mudança da atitude do paciente em relação à caminhada. MÉTODO: a seleção dos argumentos persuasivos foi baseada nas crenças comportamentais (determinantes da atitude), relacionadas à caminhada. As mensagens foram construídas com base no Modelo de Probabilidade de Elaboração e submetidas à validade de conteúdo. RESULTADOS: os dados foram analisados por meio do índice de validade de conteúdo e pela importância atribuída pelos pacientes aos argumentos persuasivos das mensagens. As crenças comportamentais positivas (i.e. reforço positivo e negativo) e a autoeficácia foram os apelos considerados importantes pelos pacientes. As mensagens com evidências de validação serão testadas em estudo de intervenção para promoção da prática de atividade física entre pacientes com DAC
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