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Major histocompatibility complex class I (MHC I) positive selection of CD8+ T cells in the thymus requires that T cell antigen receptor (TCR) signaling end in time for cytokines to induce Runx3d, the CD8-lineage transcription factor. We examined the time required for these events and found that the overall duration of positive selection was similar for all CD8+ thymocytes in mice, despite markedly different TCR signaling times. Notably, prolonged TCR signaling times were counter-balanced by accelerated Runx3d induction by cytokines and accelerated differentiation into CD8+ T cells. Consequently, lineage errors did not occur except when MHC I-TCR signaling was so prolonged that the CD4-lineage-specifying transcription factor ThPOK was expressed, preventing Runx3d induction. Thus, our results identify a compensatory signaling mechanism that prevents lineage-fate errors by dynamically modulating Runx3d induction rates during MHC I positive selection.
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Linfocitos T CD8-positivos/fisiología , Selección Clonal Mediada por Antígenos , Subunidad alfa 3 del Factor de Unión al Sitio Principal/metabolismo , Antígenos de Histocompatibilidad Clase I/metabolismo , Timo/inmunología , Animales , Diferenciación Celular , Linaje de la Célula , Células Cultivadas , Subunidad alfa 3 del Factor de Unión al Sitio Principal/genética , Citocinas/metabolismo , Antígenos de Histocompatibilidad Clase I/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Receptores de Antígenos de Linfocitos T/metabolismo , Transducción de Señal , Factores de TranscripciónRESUMEN
The maintenance of naive CD8(+) T cells is necessary for lifelong immunocompetence but for unknown reasons requires signaling via both interleukin 7 (IL-7) and the T cell antigen receptor (TCR). We now report that naive CD8(+) T cells required IL-7 signaling to be intermittent, not continuous, because prolonged IL-7 signaling induced naive CD8(+) T cells to proliferate, produce interferon-γ (IFN-γ) and undergo IFN-γ-triggered cell death. Homeostatic engagement of the TCR interrupted IL-7 signaling and thereby supported the survival and quiescence of CD8(+) T cells. However, CD8(+) T cells with insufficient TCR affinity for self ligands received prolonged IL-7 signaling and died during homeostasis. In this study we identified regulation of the duration of IL-7 signaling by homeostatic engagement of the TCR as the basis for in vivo CD8(+) T cell homeostasis.
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Linfocitos T CD8-positivos/inmunología , Homeostasis/inmunología , Interleucina-7/genética , Receptores de Antígenos de Linfocitos T/genética , Transducción de Señal/inmunología , Animales , Linfocitos T CD8-positivos/citología , Muerte Celular/inmunología , Proliferación Celular , Supervivencia Celular/inmunología , Regulación de la Expresión Génica , Interferón gamma/biosíntesis , Interferón gamma/inmunología , Interleucina-7/inmunología , Activación de Linfocitos , Ratones , Ratones Transgénicos , Receptores de Antígenos de Linfocitos T/inmunología , Factores de TiempoRESUMEN
Supportive care has become a new pilar of modern oncology, and a great deal of research is being conducted in that area, especially on immune checkpoint inhibitors (ICIs), to help fine-tune immunotherapy. Four major areas of supportive care can enhance responsiveness to cancer immunotherapy whilst minimizing adverse effects: diet (indirectly, by modulating the microbiota or directly, by modulating the immune system), physical activity (by modulating the immune system), electronic patient-reported outcomes (ePRO) (by detecting and treating immune-related adverse events early on), and co-medication management (to possibly suppress those drugs that negatively affect the efficacy of ICIs). Therefore, patients treated with ICIs could receive a systematic multimodal supportive care program encompassing regular nutritional counseling, regular physical activity under the supervision of a physical activity professional, ePRO follow-up, and regular pharmaceutical counseling. This type of approach needs to be evaluated in well-conducted randomized clinical trials.
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Ejercicio Físico , Inhibidores de Puntos de Control Inmunológico , Inmunoterapia , Neoplasias , Humanos , Neoplasias/terapia , Inmunoterapia/métodos , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Medición de Resultados Informados por el PacienteRESUMEN
Serotonin syndrome is a clinically diagnosed disorder that may occur secondary to medications that increase the release of endogenous serotonin, impair the reuptake of serotonin from the synaptic cleft, are direct serotonin receptor agonists, or increase the sensitivity of the postsynaptic serotonin receptor. In this case report, we describe the diagnosis of serotonin syndrome in a 60-year-old immunocompromised male. This case is unique, as many of the medications associated with the development of serotonin syndrome in this patient are not typically thought of as being associated with serotonin syndrome, though, in this clinical context, they combined to produce a profound pro-serotonergic effect.
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Immune checkpoint inhibitors (ICIs) have been a major breakthrough in solid oncology over the past decade. The immune system and the gut microbiota are involved in their complex mechanisms of action. However, drug interactions have been suspected of disrupting the fine equilibrium necessary for optimal ICI efficacy. Thus, clinicians are facing a great deal of sometimes contradictory information on comedications with ICIs and must at times oppose conflicting objectives between oncological response and comorbidities or complications. We compiled in this review published data on the role of the microbiota in ICI efficacy and the impact of comedications. We found mostly concordant results on detrimental action of concurrent corticosteroids, antibiotics, and proton pump inhibitors. The timeframe seems to be an important variable each time to preserve an initial immune priming at ICIs initiation. Other molecules have been associated with improved or impaired ICIs outcomes in pre-clinical models with discordant conclusions in retrospective clinical studies. We gathered the results of the main studies concerning metformin, aspirin, and non-steroidal anti-inflammatory drugs, beta blockers, renin-angiotensin-aldosterone system inhibitors, opioids, and statins. In conclusion, one should always assess the necessity of concomitant treatment according to evidence-based recommendations and discuss the possibility of postponing ICI initiation or switching strategies to preserve the critical window.
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PURPOSE: Previous work has shown that quantitative EEG measures correlate with the severity of ischemic stroke. This has not been systematically validated in patients with acute ischemic stroke who have undergone mechanical thrombectomy. METHODS: Data were collected from 73 patients who underwent mechanical thrombectomy and had a standard head set EEG performed during their hospital admission. For each patient, the global delta-alpha ratio (DAR) and its difference between the two hemispheres were calculated. Associations between the global and interhemispheric DAR difference with the patients' National Institutes of Health Stroke and Modified Rankin Scale scores at discharge and 3 months after thrombectomy were assessed. RESULTS: The interhemispheric DAR difference correlated with the National Institutes of Health Stroke scores at discharge (Spearman R = 0.41, P = 0.0008), National Institutes of Health Stroke scores at 3 months (Spearman R = 0.60, P = 0.02) and Modified Rankin Scale scores at 3 months (Spearman R = 0.27, P = 0.01). In contrast, the global DAR did not correlate significantly with any of these clinical outcomes when evaluated as continuous variables. In a multivariate logistic regression model, both the interhemispheric DAR difference (ß = 0.25, P = 0.03) and the infarct volume (ß = 0.02, P = 0.03) were independently predictive of good versus poor functional outcome (Modified Rankin Scale score ≤2 vs. >2) at 3 months. CONCLUSIONS: The quantitative EEG measure of interhemispheric slow relative to fast frequencies power asymmetry correlated with the discharge and 3-month National Institutes of Health Stroke and Modified Rankin Scale scores and provided added value to infarct volume in predicting functional outcome at 3 months. These data support the prognostic value of quantitative EEG in ischemic stroke patients who have undergone mechanical thrombectomy.
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Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/cirugía , Electroencefalografía , Humanos , Infarto , Pronóstico , Estudios Retrospectivos , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/cirugía , Trombectomía , Resultado del TratamientoRESUMEN
The detection of circulating tumor DNA (ctDNA) by liquid biopsy is taking an increasing role in thoracic oncology management due to its predictive and prognostic value. For non-small cell lung cancer, it allows the detection of molecular mutations that can be targeted with tyrosine kinase inhibitors (TKIs). We report the case of a patient with life-threatening hepatocellular failure and thrombotic microangiopathy at the diagnosis. A salvage chemotherapy was attempted, resulting in a major worsening of her general condition and the decision to stop all anti-cancer treatment. The liquid biopsy performed at the time of immunohistochemical non-small cell lung cancer diagnosis revealed within 7 days the presence of an epidermal growth factor receptor (EGFR) DEL19 activating mutation with 736,400 DNA copies/ml of plasma. It was finally decided to attempt a treatment with osimertinib (third generation anti-EGFR TKI) despite the fact that the patient was in a pre-mortem situation. Osimertinib led to a significant and prompt improvement of her performance status after only one week of treatment. The tumor tissue genotyping performed by next-generation sequencing (NGS) was available 10 days after starting TKI treatment. It revealed in addition to the EGFR DEL19 mutation, a JAK3 and EGFR amplification, highlighting the complex interactions between EGFR and the JAK/STAT signaling pathways. The first CT-scan performed after 2 months under osimertinib showed a tumor morphologic partial response. The biological assay showed a major decrease in the EGFR DEL19 mutation ctDNA levels (40.0 copies/ml). The liquid biopsy allowed an early implementation of a targeted therapy without which the patient would probably be dead. Testing for ctDNA should be discussed routinely at diagnosis in addition to tumor tissue genotyping for patient with metastatic non-small cell lung cancer that raise the clinical profile of oncogenic addiction.
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Prodigiosenes are a family of red pigments with versatile biological activity. Their tripyrrolic core structure has been modified many times in order to manipulate the spectrum of activity. We have been looking systematically at prodigiosenes substituted at the C ring with alkyl chains of different lengths, in order to assess the relevance of this substituent in a context that has not been investigated before for these derivatives: Cu(II) complexation, DNA binding, self-activated DNA cleavage, photoinduced cytotoxicity and antimicrobial activity. Our results indicate that the hydrophobic substituent has a clear influence on the different aspects of their biological activity. The cytotoxicity study of the Cu(II) complexes of these prodigiosenes shows that they exhibit a strong cytotoxic effect towards the tested tumor cell lines. The Cu(II) complex of a prodigiosene lacking any alkyl chain excelled in its photoinduced anticancer activity, thus demonstrating the potential of prodigiosenes and their metal complexes for an application in photodynamic therapy (PDT). Two derivatives along with their Cu(II) complexes showed also antimicrobial activity against Staphylococcus aureus strains.
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Antibacterianos/farmacología , Antineoplásicos/farmacología , Complejos de Coordinación/farmacología , Cobre/farmacología , ADN/efectos de los fármacos , Alquilación , Animales , Antibacterianos/síntesis química , Antibacterianos/química , Antineoplásicos/síntesis química , Antineoplásicos/química , Línea Celular , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Complejos de Coordinación/síntesis química , Complejos de Coordinación/química , Cobre/química , División del ADN/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Enterococcus hirae/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Humanos , Ratones , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Fotoquimioterapia , Pseudomonas aeruginosa/efectos de los fármacos , Ratas , Especies Reactivas de Oxígeno/metabolismo , Staphylococcus aureus/efectos de los fármacos , Relación Estructura-ActividadRESUMEN
BACKGROUND: Non-classic 21-hydroxylase deficiency is usually diagnosed in post-pubertal women because of androgen excess. Indication of systematic steroid replacement therapy is controversial because the risk of acute adrenal insufficiency is unknown. In order to specify this risk we evaluated the cortisol and aldosterone secretions in response to appropriate pharmacologic challenges. METHODS: In this prospective case-control non-inferiority study we investigated 20 women with non-classic 21-hydroxylase deficiency carrying biallelic CYP21A2 mutations and with serum 17-hydroxyprogesterone (17OHP) >10 ng/mL after stimulation with Synacthen® (tetracosactrin) and 20 age- and body mass index-matched healthy women with 17OHP after Synacthen® <2 ng/mL. Each participant underwent sequentially an insulin tolerance test to evaluate cortisol secretion and a sodium depletion test, obtained by oral administration of 40 mg of furosemide under low sodium diet (<20 mmol during 24 hours), to evaluate renin and aldosterone secretion. FINDINGS: The peak serum cortisol concentration after insulin hypoglycemia was lower in patients than in controls (mean difference -47 ng/mL, 90% CI, -66, P = 0.0026). A peak serum cortisol above a cutoff value of 170 ng/mL was obtained in all controls but only in 55% of patients (P = 0.0039). Twenty-four hours after sodium depletion, blood pressure, plasma sodium, potassium, and serum aldosterone concentrations were comparable between the two groups, but patients had higher stimulated renin concentrations than controls (P = 0.0044). INTERPRETATION: Patients with non-classic 21-hydroxylase deficiency frequently display partial cortisol insufficiency and compensated defect in aldosterone secretion. Their clinical management should systematically include assessment of adrenal functions.
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Hiperplasia Suprarrenal Congénita/fisiopatología , Aldosterona/sangre , Biomarcadores/sangre , Hidrocortisona/sangre , Hipoglucemia/patología , Seudogenes , Sodio/deficiencia , Adolescente , Adulto , Estudios de Casos y Controles , Estudios de Equivalencia como Asunto , Femenino , Estudios de Seguimiento , Francia/epidemiología , Humanos , Hipoglucemia/sangre , Hipoglucemia/epidemiología , Incidencia , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Adulto JovenRESUMEN
PURPOSE: This study examines the incidence of visually significant cystoid macular edema (CME) after glaucoma drainage implant (GDI) surgery and analyses risk factors associated with developing CME and prognosis with treatment. MATERIALS AND METHODS: In total, 185 eyes from 185 glaucoma patients (mean age, 72.46±13.94 y) who underwent GDI surgery at a tertiary eye institute were recruited. Patients were classified based on the presence (CME) or absence (No-CME) of CME. Pre-GDI and post-GDI best-corrected visual acuity, number of intraocular pressure (IOP)-lowering medications, IOP, standard automated perimetry and post-GDI complications, were recorded and compared between the 2 groups. Optical coherence tomography (OCT) was used to quantify retinal thickness and monitor CME. RESULTS: In total, 41 (22.2%) eyes developed visually significant CME after GDI surgery. Patients with CME had a higher incidence of pre-GDI nonsteroidal anti-inflammatory drug (P<0.01) use and higher number of prior glaucoma surgeries (P<0.01). CME patients had a higher (P<0.01) incidence of iritis, epiretinal membrane, and hypotony. CME eyes responded well to steroids, with resolving macular edema (458.4±151.9 vs. 322.0±92.0 µm, P<0.01) and improving visual acuity (0.73±0.48 vs. 0.56±0.56 logarithm of minimum angle of resolution, P<0.01). Both CME and non-CME groups had equivalent lowering of IOP and post-GDI glaucoma medications; with no significant elevation in IOP in the steroid-treated CME group. CONCLUSIONS: Post-GDI surgery visually significant CME rates are potentially higher in a real hospital scenario compared with controlled clinical trials. With diligent treatment, CME resolves effectively restoring visual acuity and central macular thickness.
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Implantes de Drenaje de Glaucoma/efectos adversos , Glaucoma de Ángulo Abierto/cirugía , Edema Macular/etiología , Anciano , Anciano de 80 o más Años , Síndrome de Exfoliación/fisiopatología , Síndrome de Exfoliación/cirugía , Femenino , Glaucoma de Ángulo Abierto/fisiopatología , Humanos , Presión Intraocular/fisiología , Persona de Mediana Edad , Estudios Retrospectivos , Tomografía de Coherencia Óptica/métodos , Tonometría Ocular , Agudeza Visual/fisiologíaRESUMEN
The assumption of basic properties, like self-regulation, in simple transcriptional regulatory networks can be exploited to infer regulatory motifs from the growing amounts of genomic and meta-genomic data. These motifs can in principle be used to elucidate the nature and scope of transcriptional networks through comparative genomics. Here we assess the feasibility of this approach using the SOS regulatory network of Gram-positive bacteria as a test case. Using experimentally validated data, we show that the known regulatory motif can be inferred through the assumption of self-regulation. Furthermore, the inferred motif provides a more robust search pattern for comparative genomics than the experimental motifs defined in reference organisms. We take advantage of this robustness to generate a functional map of the SOS response in Gram-positive bacteria. Our results reveal definite differences in the composition of the LexA regulon between Firmicutes and Actinobacteria, and confirm that regulation of cell-division inhibition is a widespread characteristic of this network among Gram-positive bacteria.
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Pharmaceutic studies require to analyze thousands of ECGs in order to evaluate the side effects of a new drug. In this paper we present a new support system based on the use of probabilistic models for automatic ECG segmentation. We used a bayesian HMM clustering algorithm to partition the training base, and we improved the method by using a multi-channel segmentation. We present a statistical analysis of the results where we compare different automatic methods to the segmentation of the cardiologist as a gold standard.