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Background: Exosomes are nanovesicles released by cells that can be detected in blood. Exosomes contain several molecules, such as cytokines that have potential utility as disease biomarkers. The aim of the present work is to compare six different commercial kits suitable for the clinical laboratory in relation to the efficiency and purity of exosome isolation, and their effect in subsequent cytokines analysis. Methods: Serum exosomes were obtained from 10 volunteers using six commercial kits: exoEasy, ExoQuick, Exo-spin, ME kit, ExoQuick Plus and Exo-Flow. Exosome concentrations and size distributions were quantified by nanoparticle tracking analysis. Exosome markers CD63, CD9 and TSG101 were determined by Western blot. ApoB and albumin were measured using nephelometry. S100A9, CXCL5 and CXCL12 were measured using a Luminex assay. Results: The concentration of particles obtained between different kits varied by a factor of 100. There was no correlation in particle concentrations extracted between different kits, except between ExoQuick and Exo-Flow. The highest exosome purity was achieved with ExoQuick Plus and exoEasy, while the lowest were achieved with ME and ExoQuick. Albumin was present in all exosome extracts analyzed and ApoB in all except those extracted with Exo-Flow and ME. Cytokine detection varied depending on the purification kit used and there was no correlation in cytokine concentrations between samples obtained with different kits. Conclusions: Both the sample and the type of commercial kit used affect the efficiency and purity of exosome isolation. In addition, the exosome purification method deeply affects the capability to detect and quantify cytokines.

Liquid biopsy refers to the molecular analysis in biological fluids of nucleic acids, subcellular structures, especially exosomes, and, in the context of cancer, circulating tumor cells. In the last 10 years, there has been an intensive research in liquid biopsy to achieve a less invasive and more precise personalized medicine. Molecular assessment of these circulating biomarkers can complement or even surrogate tissue biopsy. Because of this research, liquid biopsy has been introduced in clinical practice, especially in oncology, prenatal screening, and transplantation. Here we review the biology, methodological approaches, and clinical applications of the main biomarkers involved in liquid biopsy.

La diabetes mellitus tipo 2 es una patología con una enorme prevalencia y morbilidad, que van en aumento. La fractura osteoporótica se encuentra entre las denominadas complicaciones «no clásicas» de la diabetes y ha sido durante tiempo ignorada, tal vez por su complejo abordaje tanto diagnóstico como terapéutico. Las herramientas habituales para la prevención de la fractura por fragilidad, como el FRAX y la densitometría ósea, no han demostrado la suficiente eficacia en estos pacientes, ya que infraestiman el riesgo. Nuevas técnicas de evaluación ósea, como el trabecular bone score o los marcadores de remodelado óseo, podrían ser de utilidad, aunque requieren una mayor evidencia científica para recomendar su uso en la práctica clínica habitual. Las características especiales de su fisiopatología condicionan la aparición de fracturas sin existir alteraciones densitométricas, en lo que podemos calificar de «paradoja diabética».

BACKGROUND/OBJECTIVES: The validation of effective screening tools for the identification of patients with subclinical myocardial remodelling is a major clinical need. Thus, we explored the associations of circulating biomarkers of cardiomyocyte injury and stress with subclinical cardiac remodelling and dysfunction, and with biomarkers reflecting collagen turnover. METHODS: We randomly recruited 727 subjects from a general population (51.2% women; mean age 51.3 years). Measurements included echocardiographic left atrial (LA) and left ventricular (LV) structure and function, quantification of high sensitivity cardiac Troponin T (hs-cTnT), NT-proBNP, and biomarkers of collagen types I and III turnover. RESULTS: In unadjusted and adjusted analyses, the prevalence of LA enlargement (LAE), LV hypertrophy (LVH) and LV diastolic dysfunction (LVDD) increased with higher hs-cTnT (P ¿ 0.031). NT-proBNP was independently associated with LVDD (P=0.009). Both biomarkers combined yielded significant integrated discrimination and net reclassification improvements (P ¿ 0.014 and P ¿ 0.009, respectively) for LAE, LVH and LVDD, over the conventional risk factors, and were independently and positively associated with biomarkers of collagen type I turnover. In a sensitivity analysis, after excluding participants with previous cardiac diseases, our findings remained consistent. CONCLUSIONS: Our population-based study suggested that subclinical LV and LA remodelling were associated with hs-cTnT, and that, in combination with NT-proBNP, hs-cTnT showed incremental diagnostic utility over the conventional risk factors. Both biomarkers were associated with biomarkers of collagen type I turnover. Thus, biomarkers of cardiomyocyte microinjury and hemodynamic stress may stimulate fibrosis-related mechanisms and facilitate the diagnosis of subclinical LA and LV remodelling and dysfunction in the general population.

BACKGROUND & AIMS: Radioembolization may rarely induce liver disease resulting in a syndrome that is similar to veno-occlusive disease complicating bone marrow transplantation where inflammation, endothelial cell activation and thrombosis are likely involved. We hypothesized that similar mechanisms could be implicated in radioembolization-induced liver disease (REILD). Moreover, lobar radioembolization may induce hypertrophy of the non-treated hemiliver most probably by inducing liver regeneration. METHODS: In patients with hepatocellular carcinoma, we prospectively studied serum levels of markers of liver regeneration, oxidative stress, pro-inflammatory pathways, endothelial activation and coagulation parameters over 2 months after radioembolization. RESULTS: Although REILD did not occur among 14 treated patients, a decrease in effective liver blood flow was observed. Radioembolization was followed by a persistent increase in pro-inflammatory (interleukin 6 and 8) and oxidative stress (malondyaldehide) markers, an induction of endothelial injury markers (vW factor and PAI-1) and an activation of the coagulation cascade (factor VIII, PAI-1, D-Dimer) as well as a significant increase in factors related to liver regeneration (FGF-19 and HGF). CONCLUSION: Radioembolization activates liver regeneration, produces oxidative stress, activates inflammatory cytokines and induces endothelial injury with partial activation of the coagulation cascade. These findings may have implicati

Context: Bone turnover markers (BTMs) may identify changes in bone remodeling within a relatively short time interval before changes in bone mineral density can be detected. New markers such as osteoprotegerin, receptor activator of nuclear factor-B ligand, and sclerostin have emerged, but there is little information about their potential use in clinical practice. Design, Patients, and Setting: We performed an observational prospective study in pre-and postmenopausal ambulatory women (n =72 and n =152, respectively). Intervention: Postmenopausal women with osteoporosis (n =18) were treated with risedronate and calcium. Womenfilled out a questionnaire and underwent bone mineral density measurement using dual-energy x-ray absorptiometry at the time of enrollment and after 1 year of follow-up. BTMs were measured at baseline, at 6 months, and after 1 year. Results: Increased levels of N-terminal propeptide of type 1 procollagen (P1NP) and beta-type I collagen telopeptides (CTXs) were associated with low bone mineral density in the premenopausal (P =.02 and P =.04, respectively) and postmenopausal (P =.03 and P =.02) groups. The best analytical performance to diagnose osteoporosis was for = -CTX, osteocalcin, and P1NP, with areas under the curve of 0.70 (P =.005), 0.64 (P =.048), and 0.71 (P =.003). A significant decrease was found in P1NP, osteocalcin, tartrate-resistant acid phosphatase-5b, =-CTX, and bone alkaline phosphatase after 1 year of treatment (all P =.05). Conclusions: Our data suggest that measurement of beta beta-CTX and P1NP shows adequate analytical performance and could potentially be included in algorithms for the screening of osteoporosis. Furthermore, these two markers, along with osteocalcin and tartrate-resistant acid phosphatase5b, are useful to monitor the response to risedronate.

Background: The relationship between serum biomarkers and clinical expressions of COPD is limited. We planned to further describe this association using markers of inflammation and injury and repair. Methods: We studied lung function, comorbidities, exercise tolerance, BODE index, and quality of life in 253 COPD patients and recorded mortality over three years. Serum levels of Interleukins 6,8 and 16, tumor necrosis factor alpha (TNF alpha) [inflammatory panel], vascular endothelial growth factor (VEGF), and matrix metalloproteinase 9 (MMP-9)[injury and repair panel] and pulmonary and activation-regulated chemokine (PARC/CCL-18) and monocyte chemotactic protein 1 (MCP-1/CCL2) [chemoattractant panel] were measured. We related the pattern of the biomarker levels to minimal clinically important differences (MCID) using a novel visualization method [ObServed Clinical Association Results (OSCAR) plot]. Results: Levels of the inflammatory markers IL-6, TNF alpha were higher and those of injury and repair lower (p < 0.01) with more advanced disease (GOLD 1 vs. 4). Using the OSCAR plot, we found that patients in the highest quartile of inflammatory and lowest quartile of injury and repair biomarkers level were more clinically compromised and had higher mortality (p < 0.05). Conclusions: In COPD, serum biomarkers of inflammation and repair are distinctly associated with important clinical parameters and survival.

Cadena respiratoria mitocondrial y fosforilación oxidativa, ADN mitocondrial, origen de las proteínas mitocondriales, alteraciones del ADN mitocondrial y envejecimiento, enfermedades mitocondriales o citopatías mitocondriales, estudio bioquímico general de las citopatías mitocondriales.