1,568 research outputs found
Estudio del perfil genético en pacientes con Amiloidosis de cadenas ligeras
Oral Presentation [CO-130]
Introducción: Los estudios de secuenciación masiva (NGS) han permitido profundizar en el conocimiento de las gammapatías monoclonales tales como el mieloma múltiple (MM) y la macroglobulinemia de Waldesntröm’s (WM). Desafortunadamente, la baja incidencia de la amiloidosis de cadenas ligeras (AL) y la baja carga tumoral que presenta, a menudo enmascarada por un fondo policlonal de células plasmáticas (PC), explica la poca información que hay sobre la biología de la célula tumoral. Por ello, se desconoce si la AL presenta alguna mutación común como ocurre en la WM, si existen mutaciones recurrentes, y si estas podrían coincidir con las observadas en MM. Por lo tanto, el objetivo de este trabajo es realizar una secuenciación de exoma (WES) en una serie de pacientes con AL y comparar su perfil mutacional con el de MM.
Métodos: En este estudio se incluyeron 28 pacientes con AL. Se realizó un WES, incluyendo las regiones reguladoras UTR (SureSelect Human All Exon V6 + UTRs (Agilent)) en 56 muestras pareadas sorteadas de células plasmáticas patológicas y sangre periférica como muestra control. Cada muestra tumoral fue capturada por triplicado y secuenciada en la plataforma NextSeq 500 (Illumina). Para el análisis de variantes somáticas se utilizaron los programas Strelka y ANNOVAR. . Las firmas mutacionales se analizaron con el software DeconstructSigs. Para comparar el perfil mutacional de AL con MM se utilizó la base de datos MMRF CoMMpass con 895 pacientes. Además, se han determinado los reordenamientos de los genes de las inmunoglobulinas (Igs) mediante NGS.
Resultados: La cobertura media de secuenciación para las muestras de control y tumor fue de 64x y 186x, respectivamente. Se detectaron un total de 1983 SNV y 133 INDEL con una media de 71 (20-281) SNV y 5 (0-25) INDEL por paciente. Al comparar con MM (media 66 SNV y 2.5 INDEL) se observó una carga mutacional similar. Los únicos genes mutados tanto en AL como en MM fueron MUC16 (recurrencia 17% y 8%, respectivamente) e IGLL5 (recurrencia 17%, en ambas), siendo además los genes más frecuentemente mutados en AL Las firmas mutacionales más frecuentes que se identificaron fueron la 1 (desaminación espontánea de citosinas metiladas en sitios CpG), la 3 (fallo en la reparación de la ruptura de la doble cadena de ADN mediante recombinación homóloga), y la 9 (transveriones T> G en trinucleótidos ApTpN y TpTpN), identificadas en el 96%, 54% y 46% de los pacientes, respectivamente. Respecto al repertorio de los genes de las Igs, se observó que el 26% de los pacientes con AL presentan más de un clon, siendo esta heterogeneidad clonal similar a la encontrada en MM (23%). El gen IGHV3-30 fue identificado con mayor frecuencia tanto en AL como en MM, 10% y 12% de recurrencia, respectivamente.
Conclusiones: Este es el primer estudio de WES en una serie de pacientes con AL. Los resultados muestran que no hay una mutación común driver en esta enfermedad, que podrían estar implicados múltiples procesos mutacionales, y que los genes descritos más frecuentemente mutados en AL y MM no coinciden. En conjunto, estos resultados suponen un avance en el entendimiento de la patogénesis de la AL
Citraconate inhibits ACOD1 (IRG1) catalysis, reduces interferon responses and oxidative stress, and modulates inflammation and cell metabolism
Although the immunomodulatory and cytoprotective properties of itaconate have been studied extensively, it is not known whether its naturally occurring isomers mesaconate and citraconate have similar properties. Here, we show that itaconate is partially converted to mesaconate intracellularly and that mesaconate accumulation in macrophage activation depends on prior itaconate synthesis. When added to human cells in supraphysiological concentrations, all three isomers reduce lactate levels, whereas itaconate is the strongest succinate dehydrogenase (SDH) inhibitor. In cells infected with influenza A virus (IAV), all three isomers profoundly alter amino acid metabolism, modulate cytokine/chemokine release and reduce interferon signalling, oxidative stress and the release of viral particles. Of the three isomers, citraconate is the strongest electrophile and nuclear factor-erythroid 2-related factor 2 (NRF2) agonist. Only citraconate inhibits catalysis of itaconate by cis-aconitate decarboxylase (ACOD1), probably by competitive binding to the substrate-binding site. These results reveal mesaconate and citraconate as immunomodulatory, anti-oxidative and antiviral compounds, and citraconate as the first naturally occurring ACOD1 inhibitor. [Image: see text
Citraconate inhibits ACOD1 (IRG1) catalysis, reduces interferon responses and oxidative stress, and modulates inflammation and cell metabolism
Although the immunomodulatory and cytoprotective properties of itaconate have been studied extensively, it is not known
whether its naturally occurring isomers mesaconate and citraconate have similar properties. Here, we show that itaconate
is partially converted to mesaconate intracellularly and that
mesaconate accumulation in macrophage activation depends
on prior itaconate synthesis. When added to human cells in
supraphysiological concentrations, all three isomers reduce
lactate levels, whereas itaconate is the strongest succinate
dehydrogenase (SDH) inhibitor. In cells infected with influenza A virus (IAV), all three isomers profoundly alter amino
acid metabolism, modulate cytokine/chemokine release and
reduce interferon signalling, oxidative stress and the release
of viral particles. Of the three isomers, citraconate is the
strongest electrophile and nuclear factor-erythroid 2-related
factor 2 (NRF2) agonist. Only citraconate inhibits catalysis of
itaconate by cis-aconitate decarboxylase (ACOD1), probably
by competitive binding to the substrate-binding site. These
results reveal mesaconate and citraconate as immunomodulatory, anti-oxidative and antiviral compounds, and citraconate
as the first naturally occurring ACOD1 inhibitor
The QUIJOTE experiment: project status and first scientific results
We present the current status of the QUIJOTE (Q-U-I JOint TEnerife) experiment, a new polarimeter with the aim of characterizing the polarization of the Cosmic Microwave Background, and other galactic or extra-galactic physical processes that emit in microwaves in the frequency range 10–42 GHz, and at large angular scales (around 1 degree resolution). The experiment has been designed to reach the required sensitivity to detect a primordial gravitational wave component in the CMB, provided its tensor-to-scalar ratio is larger than r ∼ 0.05. The project consists of two telescopes and three instruments which will survey a large sky area from the Teide Observatory to provide I, Q and U maps of high sensitivity. The first QUIJOTE instrument, known as Multi-Frequency Instrument (MFI), has been surveying the northern sky in four individual frequencies between 10 and 20 GHz since November 2012, providing data with an average sensitivity of 80 µK beam−1 in Q and U in a region of 20, 000 square-degrees. The second instrument, or Thirty-GHz Instrument (TGI), is currently undergoing the commissioning phase, and the third instrument, or Forty-GHz Instrument (FGI), is in the final fabrication phase. Finally, we describe the first scientific results obtained with the MFI. Some specific regions, mainly along the Galactic plane, have been surveyed to a deeper depth, reaching sensitivities of around 40 µK beam−1. We present new upper limits on the polarization of the anomalous dust emission, resulting from these data, in the Perseus molecular complex and in the W43 molecular complex
Cell walls of the dimorphic fungal pathogens Sporothrix schenckii and Sporothrix brasiliensis exhibit bilaminate structures and sloughing of extensive and intact layers
This work was supported by the Fundação Carlos Chagas de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ), grants E-26/202.974/2015 and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), grants 229755/2013-5, Brazil. LMLB is a senior research fellow of CNPq and Faperj. NG acknowledged support from the Wellcome Trust (Trust (097377, 101873, 200208) and MRC Centre for Medical Mycology (MR/N006364/1). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer reviewedPublisher PD
Treatment of advanced, recurrent, resistant to previous treatments basal and squamous cell skin carcinomas with a synergistic formulation of interferons. Open, prospective study
<p>Abstract</p> <p>Background</p> <p>Aggressive non-melanoma skin cancer (deeply infiltrating, recurrent, and morphea form lesions) are therapeutically challenging because they require considerable tissue loss and may demand radical disfiguring surgery. Interferons (IFN) may provide a non-surgical approach to the management of these tumors. The aim of this work was to evaluate the effect of a formulation containing IFNs-α and -γ in synergistic proportions on patients with recurrent, advanced basal cell (BCC) or squamous cell skin carcinomas (SCSC).</p> <p>Methods</p> <p>Patients with extensive, recurrent, resistant to other procedures BCC or SCSC received the IFN formulation peri- and intralesionally, three times per week for 3 weeks. They had been previously treated with surgery and/or radiotherapy or chemotherapy. Thirteen weeks after the end of treatment, the original lesion sites were examined for histological evidence of remaining tumor.</p> <p>Results</p> <p>Sixteen elder (median 70 years-old) patients were included. They beared 12 BCC and 4 SCSC ranging from 1.5 to 12.5 cm in the longest dimension. At the end of treatment 47% CR (complete tumor elimination), 40% PR (>30% tumor reduction), and 13% stable disease were obtained. None of the patients relapsed during the treatment period. The median duration of the response was 38 months. Only one patient with complete response had relapsed until today. Principal adverse reactions were influenza-like symptoms well known to occur with interferon therapy, which were well tolerated.</p> <p>Conclusion</p> <p>The peri- and intralesional combination of IFNs-α and -γ was safe and showed effect for the treatment of advanced, recurrent and resistant to previous treatments of BCC and SCSC in elder patients. This is the first report of such treatment in patients with advance non-melanoma skin cancer. The encouraging result justifies further confirmatory trials.</p> <p>Trial registration</p> <p>Current Controlled Trials RPCEC00000052.</p
The stress-responsive kinase DYRK2 activates heat shock factor 1 promoting resistance to proteotoxic stress
To survive proteotoxic stress, cancer cells activate the proteotoxic-stress response pathway, which is controlled by the transcription factor heat shock factor 1 (HSF1). This pathway supports cancer initiation, cancer progression and chemoresistance and thus is an attractive therapeutic target. As developing inhibitors against transcriptional regulators, such as HSF1 is challenging, the identification and targeting of upstream regulators of HSF1 present a tractable alternative strategy. Here we demonstrate that in triple-negative breast cancer (TNBC) cells, the dual specificity tyrosine-regulated kinase 2 (DYRK2) phosphorylates HSF1, promoting its nuclear stability and transcriptional activity. DYRK2 depletion reduces HSF1 activity and sensitises TNBC cells to proteotoxic stress. Importantly, in tumours from TNBC patients, DYRK2 levels positively correlate with active HSF1 and associates with poor prognosis, suggesting that DYRK2 could be promoting TNBC. These findings identify DYRK2 as a key modulator of the HSF1 transcriptional programme and a potential therapeutic target
Sexto reporte de eventos adversos con tratamientos biológicos en Argentina. Informe del registro BIOBADASAR
Objetivo: actualizar los resultados del registro BIOBADASAR sobre seguridad, duración y causas de interrupción del tratamiento luego de 8 años de seguimiento.
Métodos: BIOBADASAR es un registro de seguridad de terapias biológicas establecido por la Sociedad Argentina de Reumatología. Se presenta la descripción de BIOBADASAR 3.0, una cohorte compuesta por 53 centros de Argentina seguidos prospectivamente desde agosto de 2010 hasta enero de 2018
- …